Department of Computer Science, University of Oxford Projects All

Department of Computer Science, University of Oxford Projects All http://www.cs.ox.ac.uk/projects/ All en-gb 360 Tue, 14 Feb 2012 01:21:35 GMT Tue, 14 Feb 2012 01:21:35 GMT All http://blogs.law.harvard.edu/tech/rss/ RoboCup International Robot Competitions http://www.cs.ox.ac.uk/projects/RoboCup/ This is a placeholder for the general work we do in the RoboCup competitions Department of Computer Science, University of Oxford Projects All oucl-All-RoboCup Fri, 10 Feb 2012 02:23:47 GMT PrOQAW: Probabilistic Ontological Query Answering on the Web http://www.cs.ox.ac.uk/projects/PrOQAW/ The next revolution in Web search as one of the key technologies of the Web has just started with the incorporation of ideas from the Semantic Web, aiming at transforming current Web search into some form of semantic search and query answering on the Web, by adding meaning to Web contents and queries in the form of an underlying ontology. This also allows for more complex queries, and for evaluating queries by combining knowledge that is distributed over many Web pages, i.e., by reasoning over the Web. Realizing such semantic search and query answering on the Web by adding ontological meaning to the current Web conceptually means annotating Web pages and their contents relative to that ontology, i.e., relating Web pages and their contents to and thus also via that ontology. From a practical perspective, one of the most promising ways of realizing this is to perform data extraction from the current Web relative to the underlying ontology, store the extracted data in a knowledge base, and realize semantic search and query answering on this knowledge base. There are recently many strong research activities in this direction. A major unsolved problem in the above context is the principled handling of uncertainty: In addition to natural uncertainty as an inherent part of Web data, one also has to deal with uncertainty resulting from automatically processing Web data. The former also includes uncertainty due to incompleteness and inconsistency in the case of missing and over-specified information, respectively. The latter includes uncertainty due to, e.g., the automatic annotation of Web pages and their contents, the automatic extraction of knowledge from the Web, matching between different related ontologies, and the integration of distributed Web data sources. The central goal of the proposed research is to develop a family of probabilistic data models for knowledge bases extracted from the Web relative to an underlying ontology, along with scalable query answering algorithms, which may serve as the backbone for next-generation technologies for semantic search and query answering on the Web. We believe that such probabilistic data models and query answering algorithms can be developed by integrating ontology languages, database technologies, and formalisms for managing probabilistic uncertainty in the context of the Web. The objectives include developing probabilistic data models, developing algorithms for ranking and query answering, identifying useful scalable fragments, and practically evaluating our results.   Department of Computer Science, University of Oxford Projects All oucl-All-PrOQAW Fri, 10 Feb 2012 02:23:47 GMT Probabilistic Semantic Query Answering on the Web http://www.cs.ox.ac.uk/projects/GoogleAward/ For many people, the Web has started to play a fundamental role as a means of providing and searching for information and services. Searching the Web in its current form, however, is not always a joyful experience, since today’s search engines often are not capable of adequately responding to complex queries. Although the information is available, it is necessary to go through the cumbersome process of posing multiple simple queries and combining the answers in order to get the desired response. The next revolution in Web search as one of the key technologies of the Web has just started with the incorporation of ideas from the Semantic Web, which aims at transforming current Web search into some form of semantic search on the Web by adding meaning to Web contents and search queries, which also allows for more complex queries, whose evaluation involves reasoning over the Web. The goal of this project is to develop a family of probabilistic data models for knowledge bases extracted from the Web, along with scalable query answering algorithms, which may serve as the backbone for such next-generation technologies for semantic search and query answering on the Web. Department of Computer Science, University of Oxford Projects All oucl-All-Google Award Fri, 10 Feb 2012 02:23:47 GMT New Foundational Structures for Engineering Verified multi-UAVs http://www.cs.ox.ac.uk/projects/EPSRCUAVAutonomy/ In March 2011, Japan suffered from its biggest earthquake and devastating tsunami. Severe damage were inflicted on its Fukushima nuclear plants and more than 100,000 people had to be evacuated after the radiation levels became unsafe. Workers were not able to operate on site, preventing them from securing safety at the atomic power plant and averting a major radiation leak. One month after the disaster, in order to assess the severity of the damage to the nuclear plant from above, a small aerial vehicle equipped with cameras was sent to take pictures and videos of the affected areas. The video footage obtained brought valuable information to the rescue teams that could not have been acquired otherwise. But the use of aerial vehicles still remains limited by the fact that they require a remote operator at transmission range to control them. It is also necessary to have an operator to control the camera and interpret the data. In order to work autonomously, these systems need to be highly intelligent and rational so that they can become reliable: they must have high levels of knowledge to accomplish their AI-complex missions which occur in any other information environment. This implies that they should adapt to any unexpected situations such as recent changes not reflected in prior information on the environment and possible loss of GPS due to obstructing buildings or indoor exploration; reliable operation under such conditions would, for instance, enable them to return safely to their base station. In a multi-UAV setting, they should additionally be able to communicate with each other to simplify their goals, to learn from each other's information, and to update and share their knowledge. Given that any mission is unique in terms of deployment areas, tasks and goals to be achieved, etc., and can be critical in the sense that human lives may be involved, the implementation must be verified to be correct with respect to a formal specification. A famous example of an implementation error and a failure to comply with the specification is the self-destruction of Ariane 5 in 1996 immediately after take-off, caused by a numeric overflow due to an implementation that was not suitable for all possible situations. In 1996, the Lockheed Martin/Boeing Darkstar long-endurance UAV crashed following what the Pentagon called a "mishap [..] directly traceable to deficiencies in the modelling and simulation of the flight vehicle". To achieve the reliability required, we will need to develop a formalism that represents the sets of actions each Unmanned Aerial Vehicle (UAV) can perform while allowing capture of the kinetic constraints of the UAVs. We will then verify that the behaviours of each UAV modelled using this formalism lead to the individual or overall goal of the mission they are to achieve. These need to be extended from individual behaviours to a cooperative level amongst the multiple UAVs. Next, we plan to link the low-level code to high-level abstraction and verify it via advanced model-checking techniques. Finally, logical tools will be used to exhaustively reason about learning as a result of information flow among UAVs and their environment. Department of Computer Science, University of Oxford Projects All oucl-All-EPSRC UAV Autonomy Fri, 10 Feb 2012 02:23:47 GMT Structures at the Interface of Physics and Computer Science http://www.cs.ox.ac.uk/projects/SIPCS/ This project aims to fund a network to support an emerging research community working at the interface of Computer Science, Physics and Mathematics. The common theme is the use of high-level mathematical structures such as Category Theory. These structures have already proved important in various specific areas within these disciplines. It has recently been becoming clear that they can be used in a unified and very powerful way, and that the same structures occur across these disciplines. This has led to a lot of exciting research, which has been bringing established researchers together, and attracting students and young researchers into the area. The aim of the network is to foster and support these activities, and to nurture the development of an emerging research community, centred in the UK, which is at the forefront of these exciting developments. We will do this by supporting regular meetings, providing travel money for young researchers to attend conferences and make research visits, and managing a strong web presence which can act as a hub for the community. This will help to make the UK attractive to the best researchers in the world on the topic of the network, and will enable it to take a leading role in future developments. Department of Computer Science, University of Oxford Projects All oucl-All-SIPCS Fri, 10 Feb 2012 02:23:47 GMT Underground Animal Tracking & Mapping in 3D http://www.cs.ox.ac.uk/projects/UnderTracker/ Wildlife tracking using wireless sensor networks has garnered a great deal of attention and research, since the seminal ZebraNet project monitored zebras with mobile nodes in 2002. However, research to date has concentrated on monitoring animals when they are above ground. It is currently impossible to automatically monitor animals whilst they are underground. The main reason for this is that radio waves are severely attenuated by layers of soil, to the point of being unusable. There is a strong need for a system that can localize burrowing animals when they are within their dens or tunnels, in order to better understand their behaviour and habits. A prime example of this is the European badger - badgers are a protected species in the UK, yet are subject to widespread culling due to their possible link to bovine TB. By monitoring internal sett conditions and animal interactions underground, a better understanding of infection could potentially be obtained. To tackle these issues, I propose the use of low frequency magnetic fields (i.e. the principle of magneto-induction, MI), which are able to penetrate soil without attenuation, to provide ultra-low power three dimensional localization of wild animals within their burrows. Data from tracking collars will be forwarded by conventional high frequency radio links when the animal is above ground, meaning that the animal does not need to be recaptured to obtain the stored information. By mapping animal movements over time, the subterranean tunnel architecture itself will be determined, something which can currently only be obtained, destructively, through excavation. Sensors within the tunnel will monitor gas concentrations and temperature gradients, which will help to explain how animals achieve suitable ventilation underground and maintain body temperature. To investigate animal behaviour, tracking collars will be equipped with miniature sensors, such as accelerometers and magnetometers, which will record motion and energetics. To reduce data volumes, tracking collars will automatically characterize animal behaviour primitives, such as walking or sleeping. To further increase the rate of "learning" this information, tracking collars will share motion features, forming a distributed knowledge base. Thus, this research proposes a broad animal monitoring and tracking system, which will reveal a complete picture of animal life underground, for the first time. To achieve the goals of the research a close collaboration with the Wildlife Conservation Research Unit at the University of Oxford will be formed. They will guide the design of the tracking collars and attach them to suitable badgers during regular research undertaken in Wytham Woods, Oxfordshire. Their expertise is also vital in framing the research to address biologically relevant questions. Data from this system will also be used by researchers in the University of Cambridge Computing Laboratory, to investigate social contact networks. Ultimately this insight into the detail of badgers' lives will help to unravel the true extent with which they interact with each other, and shed light not just on the behavioural-ecology of this species, but investigate their social systems and address important questions concerning the transmission of disease. Department of Computer Science, University of Oxford Projects All oucl-All-UnderTracker Fri, 10 Feb 2012 02:23:47 GMT Validation of Concurrent Software Across Abstraction Layers http://www.cs.ox.ac.uk/projects/CPROVER/ The cost of software quality assurance (QA) dominates the cost of IT development and maintenance projects. QA is frequently on the critical path to market. Effective software QA is therefore decisive for the competitiveness of numerous industries that rely on IT, and essential for government tasks that rely heavily on IT. This research programme will provide a pragmatic solution to the most pressing issue in software QA in mainstream software engineering: the use of concurrency. Programmers make use of numerous favors of concurrency in order to achieve better scalability, savings in power, increase reliability, and to boost performance. The need for software that makes diligent use of concurrent computational resources has been exacerbated by power-efficient multi-core CPUs, which are now widely deployed, but still unfertilized due the lack of appropriate software. Concurrent software is particularly difficult to test, as bugs depend on particular interlavings between the sequential computations. Defects are therefore difficult to reproduce and diagnose, and often elude even very experienced programmers. We propose to develop new, ground-braking reasoning and testing technology for this kind of software, with the goal of cutting the staff effort in QA of concurrent effort in half. We will use a tightly integrated combination of scalable and performant testing technology and Model Checking and abstract interpretation engines to prune the search. Every aspect of the research programme is geared towards improving the productivity of the average application programmer. Our theories and reasoning technology will therefore be implemented in a seamless fashion within the existing, well-accepted programming environments Visual Studio and Eclipse, in close collaboration with Microsoft and IBM. Department of Computer Science, University of Oxford Projects All oucl-All-CPROVER Fri, 10 Feb 2012 02:23:47 GMT Foundational Structures for Compositional Meaning http://www.cs.ox.ac.uk/projects/FSCM/ Words are the building blocks of sentences, yet meaning of a sentence goes well beyond meanings of the words therein. Indeed, while we do have dictionaries for words, we don't seem to need them to infer the meaning of a sentence from meanings of its constituents. Discovering the process of meaning assignment in natural languages is one of the most foundational issues in linguistics and computer science, whose findings will increase our understanding of cognition and intelligence and may assist in applications to automating language-related tasks, such as document search as done by Google. To date, the compositional logical and the distributional probabilistic models have provided two complementary partial solutions to the problem of meaning assigning in natural languages. The logical approach is based on classic ideas from mathematical logic, mainly Frege's principle that meaning of a sentence can be derived from the relations of the words in it. The distributional model is more recent, it can be related to Wittgenstein's philosophy of 'meaning as use', whereby meanings of words can be determined from their context. The logical models have been the champions on the theory side, whereas in practice their probabilistic rivals have provided the best predictions. This two-sortedness of defining properties of meaning: 'logical form' versus 'contextual use', has left the question of 'what is the foundational structure of meaning?' even more open a question than before. This project has ambitious and far-reaching goals; it aims to bring together these two complementary concepts to tackle the question. And it aims to do so by bridging the fields of linguistics, computer science, logic, probability theory, category theory, and even physics. Its scope is foundational, multi and inter disciplinary, with an eye towards applications. Meaning assignment is a dynamic interactive process involving grammar and logic as well as meanings of words. Both of the two existing approaches to language miss a crucial aspect of this process: the logical model ignores meanings of words, the distributional model ignores the grammar and logic. We aim to model the entire dynamic process alongside the following three strands of integration, foundations, and applications. (I) In integration we develop a process of meaning assignment that acts with the compositional forms of the logical model on the contextual word-meaning entities of the distributional model. (II) In foundations, we go beyond classical logical principles of compositionality and context-based models of meaning to develop more fundamental processes of meaning assignments based on novel information-flow techniques, mainly from physics, but also from other linguistic approaches and other models of word meaning, such as ontological domains and conceptual spaces. (III) In applications, we evaluate our theories against naturally occurring data and apply the results to practical issues based on meaning inference and similarity, e.g. in search. To be able to work with logical connectives in Google, one needs to re-enter them by hand in the 'advanced search' tab, by manually decomposing the logical structure of the sentence and moreover providing the extra context for their different meanings. This is fundamentally non-compositional and goes against the spirit of automated search. It is exactly here that the lack of compositional methods in meaning assignment causes practical problems and where our compositional methods become of use. Hence, we aim to put forward our results to tackle such problems, e.g. to be able to use our sentence similarity models for paraphrasing, question-answering, and retrieving documents that have the same meaning and/or are about the same subject. Our proposed partnership with Google, ensures access to real life data and helps implementation and applicability of our methods in small and large scales. Department of Computer Science, University of Oxford Projects All oucl-All-FSCM Fri, 10 Feb 2012 02:23:47 GMT Validating Changes and Upgrades in Networked Software http://www.cs.ox.ac.uk/projects/PINCETTE/ The vision of PINCETTE is to solve the problem of high cost of changes by introducing an automated framework and methodology, and a mix of technologies to identify the impact of changes that derive from intra-component changes (due to error fixing and functionality enhancement) and from component replacement within a single product and a product family. This methodology improves the reliability of networked software by implementing an innovative solution for the automatic detection, localization, and repair of program bugs. Department of Computer Science, University of Oxford Projects All oucl-All-PINCETTE Fri, 10 Feb 2012 02:23:47 GMT Autonomous Ubiquitous Sensing http://www.cs.ox.ac.uk/projects/sensing/ Wireless sensor networks have a multitude of applications, for example in environmental monitoring, autonomous transport, or intelligent buildings. There are significant challenges in engineering and programming of effective sensor-based systems, in view of resource limitations of the devices and unreliability of wireless links. At the same time, sensor networks are increasingly often deployed in safety‐critical contexts that require sound and autonomous decision making and guarantees on their correct behaviour. This research will bring together two hitherto separate streams of work: (1) Trigoni’s group, focused on developing systems and novel algorithmic techniques for data collection in sensor networks, and (2) Kwiatkowska’s VERIWARE project, which aims to develop pioneering methodology and software tools to ensure the reliability and correct behaviour for such devices, thus enabling testbed experimentation and evaluation of the techniques that is not feasible as part of existing projects. Department of Computer Science, University of Oxford Projects All oucl-All-sensing Fri, 10 Feb 2012 02:23:47 GMT Modelling and simulation environment for systems medicine (Chronic obstructive pulmonary disease -COPD- as a use case) http://www.cs.ox.ac.uk/projects/synergy/ Synergy will develop a simulation environment and a decision-support system aiming at enabling deployment of systems medicine. The three core elements are a knowledge base (KB), an inference engine (IE), and a graphical visualisation environment (GVE). The project focuses on patients with chronic obstructive pulmonary disease (COPD). The KB will include five well established physiological models addressing: 1) Central and peripheral O2 transport and utilization, 2) Pulmonary gas exchange, 3) Regional-lung heterogeneities in ventilation and perfusion, 4) Skeletal muscle bioenergetics, and 5) Mitochondrial reactive oxygen species (ROS) generation. These models will be written in systems biology markup language (SBML) and vertically integrated. Ontologies will be used as the default knowledge-representation system. The KB will include multi-level data from experimental studies (BioBridge), data from a multicentre longitudinal study on COPD phenotyping (PAC-COPD) and public datasets. The IE will enable to explore associations over the KB, perform transversal multi-scale model integration and related simulations including interactions among O2-availability/O2-utilization, ROS generation, systemic inflammation and abnormal tissue remodelling. The Web-based GVE will facilitate relevant simulations in a more intuitive way with respect to the state of the art, addressing two main user profiles: bio-researchers and clinicians. The focus will be on underlying mechanisms of COPD phenotypes associated with poor prognosis. Disease model validation and refinement will be done using a well-established, large dataset (ECLIPSE) together with experimental studies designed to test “in silico” generated hypotheses. Besides the use of the simulation environment by bio-researchers for optimal experimental design, the Synergy platform will be a relevant decision-support tool for integrated healthcare strategies aiming at modulating the evolution of COPDs. Department of Computer Science, University of Oxford Projects All oucl-All-synergy Fri, 10 Feb 2012 02:23:47 GMT Airway Disease Predicting Outcomes through Patient Specific Computational Modelling http://www.cs.ox.ac.uk/projects/AirPROM/ The airways diseases asthma and chronic obstructive pulmonary disease affect over 400 million people world-wide and cause considerable morbidity and mortality. Airways disease costs the European Union in excess of €56 billion per annum. Current therapies are inadequate and we do not have sufficient tools to predict disease progression or response to current or future therapies. Our consortium, Airway Disease PRedicting Outcomes through Patient Specific Computational Modelling (AirPROM), brings together the exisiting clinical consortia (EvA FP7, U-BIOPRED IMI and BTS Severe Asthma), and expertise in physiology, radiology, image analysis, bioengineering, data harmonization, data security and ethics, computational modeling and systems biology. We shall develop an integrated multi-scale model building upon existing models. This airway model will be comprised of an integrated 'micro-scale' and 'macro-scale' airway model informed and validated by omic data and ex vivo models at the genome-transcriptome-cell-tissue scale and by CT and functional MRI imaging coupled to detailed physiology at the tissue-organ scale utilising Europe’s largest airway disease cohort. Validation will be undertaken cross-sectionally, following interventions and after longitudinal follow-up to incorporate both spatial and temporal dimensions. AirPROM has a comprehensive data management platform and a well-developed ethico-legal framework. Critically, AirPROM has an extensive exploitation plan, involving at its inception and throughout its evolution those that will 'develop' and 'use' the technologies emerging from this project. AirPROM therefore will bridge the critical gaps in our clinical management of airways disease, by providing validated models to predict disease progression and response to treatment and the platform to translate these patient-specific tools, so as to pave the way to improved, personalised management of airways disease. Department of Computer Science, University of Oxford Projects All oucl-All-AirPROM Fri, 10 Feb 2012 02:23:47 GMT Query Rewriting for Expressive Ontology Languages http://www.cs.ox.ac.uk/projects/QueRe/ <div>Background and Motivation:</div><div> </div><div>Critical decisions in industry, science, government, and healthcareare are increasingly based on information derived from data sources whose number, size and heterogeneity continue to grow at a phenomenal rate. Improved access to and exploitation of such data is thus becoming critical to both our future competitiveness and our quality of life. One such example in the telecoms industry relates to the organisation and management of global communications networks, which has become highly complex, and involves the adjustment in real time of numerous parameters. Decisions on how to adjust these parameters can have a huge impact on performance and on profitability. These decisions are based on information derived from a large number of data sources, ranging from historical data to data streaming from monitoring equipment.</div><div> </div><div>In order to meet the challenges presented by this kind of application, a new generation of Ontology-Based Information Systems (OBISs) is beginning to emerge. These systems aim to offer high performance and large storage capacities, while at the same time exploiting rich knowledge about the application domain captured in ontologies; this knowledge is used to present a unified view over the data sources, provide a domain-centric vocabulary for use in queries, deal with incomplete and semi-structured data, and enrich query answers with implicit information.  The hope is that OBISs can be realised via a principled synthesis of ontological reasoning and database management techniques in a flexible architecture that will enable them to access data directly from different kinds of data repository, exploit different kinds of query answering technology, and adapt to a wide range of different application settings, while still providing formal guarantees about the quality of query answers.</div><div> </div><div>Currently, all practical approaches to building OBISs rely on query answering via query rewriting: answers to a query q over an ontology O and a database instance DB are computed by first rewriting q (using O) into another query q' and then evaluating q' over DB. Query rewriting means that query evaluation can be delegated to existing information systems and thus exploit the capabilities that they provide, including robust scalability and the ability to handle rapidly changing data. However, existing query rewriting techniques have focused on reducing the expressivity of the ontology language in order to obtain formal tractability guarantees; this seriously restricts the modelling capabilities of the system, while not necessarily delivering robust scalability in practice.</div><div> </div><div>The goal of the project is to design practically effective query answering algorithms for more expressive ontology languages with features such as transitivity and equality, and demonstrating that OBISs based on such languages can be effectively deployed in applications. In achieving these goals we will work closely with <a href="#mce_temp_url#">Alcatel-Lucent Bell Labs</a>, who have extensive technical expertise in this area, as well as motivating applications in the telecoms domain.</div><div> </div><div>Technical Details:</div><div> </div><div>Due to the fundamental trade-off between ontology language expressivity and query answering complexity, the currently prevalent view is that Ontology-Based Information Systems (OBISs) should use ontology languages that allow for first-order reducibility of query answering, with the low data complexity of the resulting algorithm often being given as a supporting argument. Reasoning with individual equality, transitivity, recursive axioms, or any kind of disjunctive information is LogSpace-hard in data complexity, which prevents first-order reducibility, so these features were excluded from OBIS languages such as OWL 2 QL. Such features, however, are often needed in practice; for example, transitivity is needed to describe part-whole relationships, and equality is critical in information integration.  Furthermore, even with very restricted ontology languages, the existing query rewriting algorithms produce rewritings whose size is of the order ((|O| . |q|)^|q|), where |q| and |O| are the sizes of the original query and the ontology, respectively. Data complexity is useful only when the size of the query is negligible w.r.t. the size of the data; but then, since the rewritings can be large, the low data complexity of query answering via rewriting does not provide a realistic estimate of performance in practice. Thus, while seriously restricting the ontology language, first-order reducibility does not provide a practical scalability guarantee.</div><div> </div><div>The technical challenge of this project is to develop a new approach to query answering in OBISs. On the one hand, in order to accommodate the expressivity required in practice, more expressive languages should be considered as targets for query rewriting. On the other hand, finer-grained complexity measures are needed in order to identify assumptions about the content and usage of the OBIS under which scalability can still be guaranteed. </div><div> </div><div>Regarding more expressive targets for query rewriting, first steps in this direction have already been taken: if an ontology O is expressed in the DL ELHIO, a conjunctive query q over O can be rewritten into a Datalog query q'.  The polynomial data complexity of Datalog may be too high in general; however, little is known about using languages with data complexity between AC0 and PTime as targets for query rewriting. Regular path queries (RPQs) are a promising candidate since they provide a limited form of recursion. RPQs were used as the basis for the query languages in semi-structured databases, so a rewriting approach based on RPQs should allow for ontology-based access to semi-structured data.</div><div> </div><div>Regarding finer-grained complexity measures, in related fields such as propositional satisfiability, constraint satisfaction and conjunctive query answering, measures based on (hyper)treewidth have proved very effective. Adapting such measures to OBISs, and developing query answering algorithms that exploit them, is thus an important research problem. It is currently unknown whether assumptions about the structure of data (rather than on the structure of the ontology and/or the query) may be used to obtain practically effective query answering algorithms. Furthermore, determining classes of ontology languages and/or queries that admit `small' rewritings is an important and practically relevant open problem.</div><div> </div><div>Some usage scenarios may also allow alternative architectures for OBISs to be considered.  For example, if the ontology and the data change relatively infrequently, ontology-based ISs could be based on the "combined" query answering techniques, where some entailed facts are materialised in the data. It is, however, currently unclear whether these can be extended to expressive languages such as Horn-SHIQ and the related dependency classes. Furthermore, if the data changes more frequently, the cost of recomputing the preprocessed database instance may be prohibitive; in such cases, however, an incremental maintenance approach may be efficacious.</div><div> </div><div> </div> Department of Computer Science, University of Oxford Projects All oucl-All-QueRe Fri, 10 Feb 2012 02:23:47 GMT LogMap: Logic-based Methods for Ontology Mapping http://www.cs.ox.ac.uk/projects/LogMap/ Ontologies are extensively used in biology and medicine. A prominent example of a bio-medical ontology is SNOMED CT, which is a core component of the NHS patient record service. Other examples include the Foundational Model of Anatomy (FMA) and the National Cancer Institute Thesaurus (NCI). Ontologies such as SNOMED CT, FMA, and NCI are gradually superseding the existing medical classifications and are becoming core platforms for accessing, gathering, and sharing medical knowledge and data. To exchange or migrate data between ontology-based applications, it is crucial to establish correspondences (or mappings) between their ontologies. Creating such mappings manually is often unfeasible due to the size and complexity of modern ontologies. Therefore, the problem of automatically generating mappings between ontologies (often referred to as the ontology matching, ontology alignment, or ontology mapping problem) has been investigated extensively in recent years. Despite the already mature state of the art, bio-medical ontologies still pose serious challenges to existing techniques. First, carefully-curated mapping sets used in bio-medical information integration, such as UMLS Metathesaurus, often contain errors and lack important information. Second, existing mapping generation tools do not scale to the size of modern bio-medical ontologies. Finally, the developers of bio-medical information integration and migration systems based on ontologies currently lack the necessary tool support. In this research, we aim to address each of these needs. Therefore, we have identified three main objectives: <ol> <li>To develop general principles and specific techniques to efficiently detect and repair potential errors and discover missing information in manually-curated mapping sets, such as the UMLS Metathesaurus.</li> <li>To develop computationally efficient algorithms for generating mappings between large-scale ontologies, while minimising the number of errors and the amount of missing information.</li> <li>To design and implement a prototype with core functionality for mapping generation and management, as well as for the translation and migration of ontology data.</li> </ol> Our main research hypothesis is based on the observation that existing techniques for ontology mapping often disregard the logic-based semantics of the input ontologies. As a result, they fail to take advantage of the available semantics, and of the highly effective reasoning services for modern ontology languages. We are proposing to rethink the foundations underlying the current state-of-the art in the field by incorporating reasoning-based techniques in each of the steps of the ontology mapping process. We also intend to go even further and make our techniques practical and ready to be used in applications. To this end, we aim to develop suitable heuristics that can be efficiently implemented. The research is based on our preliminary empirical evidence which suggests the potential benefits of logic-based heuristic techniques when analysing existing mappings between biomedical ontologies. We expect that our results will be directly relevant to the users of ontology-based systems in the bio-medical domain, where knowledge and data integration is a matter of major concern.  Department of Computer Science, University of Oxford Projects All oucl-All-LogMap Fri, 10 Feb 2012 02:23:47 GMT Trustworthy Clouds - Privacy and Resilience for Internet-scale Critical Infrastructure http://www.cs.ox.ac.uk/projects/TCLOUDS/ Protecting critical infrastructures providing communications, energy, or healthcare presents increasing ICT challenges as ICT itself has become vital to them. Internet-scale ICT infrastructures (“Infrastructure Clouds”) promise scalable virtualised computing, network, and storage resources over the Internet. They provide scalability and cost-efficiency but pose significant new privacy and resilience challenges. Clouds may evolve into a single point of failure, threaten all dependent ICT, and put the Future Internet at risk. TCLOUDS builds a resilient Future Internet platform by progress in four areas: <UL> <LI>Addressing the legal and business implications while building a regulatory framework for enabling privacy-enhanced cross-border infrastructure clouds.</LI> </UL> <UL> <LI>Architecture and prototypes for a federation of trustworthy infrastructure clouds that build on complementary and mutually re-enforcing technical approaches:</LI> </UL> <BLOCKQUOTE> <OL> <LI>A Trustworthy Infrastructure Cloud enables individual providers to offer more resilient and privacy-aware infrastructure clouds accessible via open interfaces.</LI> <LI>Privacy and Resilience for Commodity Clouds enables end users to put a security layer on top of existing commodity infrastructure clouds to enforce their security objectives. This enables integration of commodity clouds into the TCLOUDS federation.</LI> <LI>Federated Cloud-of-cloud Middleware offers privacy-protection and resilience beyond any individual cloud. This expands trust from trusted (enterprise-internal) clouds to less trusted (off-shored) ones, or federates a set of partially trusted providers into a trustworthy and adaptive federation that furthermore prevents lock-in to a given dominating offering.</LI> </OL> </BLOCKQUOTE> <UL> <LI>Validation and impact through cloud scenarios:</LI> </UL> <BLOCKQUOTE> <OL> <LI>Smart power grids connect renewable energy sources and users. It is a premier example of an Internet of Things.</LI> <LI>Home healthcare provides prophylaxis to citizens. We focus on the privacy and usability challenges of cross-border usage of personal data. Collaboration with complementary standardisation and FP7 projects maximises impact and fosters an Open European Trustworthy Cloud ecosystem.</LI> </OL> </BLOCKQUOTE> Oxford's involvement is chiefly in the scientific activity of the project, developing previously sketched research architectures into viable detailed designs, and undertaking analysis of these. Furthermore UOXF will be in charge of end-to-end security for applications as well as job security manager for controlled data access. The University will play an important role in dissemination through scientific publications and conferences, and continue to play host to conferences and summer schools in relevant topics. Department of Computer Science, University of Oxford Projects All oucl-All-TCLOUDS Fri, 10 Feb 2012 02:23:47 GMT webinos: Secure WebOS Application Delivery Environment http://www.cs.ox.ac.uk/projects/webinos/ webinos is an EU-funded project aiming to deliver a platform for web applications across mobile, PC, home media (TV) and in-car devices.   The webinos project will define and deliver an Open Source Platform and software components for the Future Internet in the form of web runtime extensions, to enable web applications and services to be used and shared consistently and securely over a broad spectrum of converged and connected devices, including mobile, PC, home media (TV) and in-car units. webinos in a Nutshell: Promoting a “single service for every device” vision, webinos will move the existing baseline of web development from installed applications to services, running consistently across a wide range of connected devices, ensuring that the technologies for describing, negotiating, securing, utilizing device functionalities and adapting to context are fit for purpose. Innovations in contextual description will be broad covering but not limited to device capabilities, network access, user identity and preferences, location, behaviourally induced properties and finally the more complex issue of the users’ social network context and social media engagement. webinos will boost the industry migration towards web-based services. webinos can back this by providing inter-operable, standardised, open source technology utilizable across domains with direct commercially exploitable value. webinos will also act as an industry catalyst to encourage collaboration and discourage fragmentation in this space. There are strong industry moves towards Internet friendly and Internet integrated offerings, and there exists a window of opportunity to place the webinos technology on a robust open foundation that will remove economic barriers to engagement, embody policy on data privacy in concrete technology and creating a centre of web centric expertise. (webinos was initially known as WAX).  Department of Computer Science, University of Oxford Projects All oucl-All-webinos Fri, 10 Feb 2012 02:23:47 GMT Transatlantic TUmour MOdel Repositories http://www.cs.ox.ac.uk/projects/TUMOR/ The project aims at developing a European clinically oriented semantic-layered cancer digital model repository from existing EU projects that will be interoperable with the US grid enabled semantic-layered digital model repository platform at CViT.org (Center for the Development of a Virtual Tumor, Massachusetts General Hospital (MGH), Boston, USA) which is NIH/NCI-caGRID compatible. This interoperable, CViT interfaced, environment will offer a range of services to international cancer modelers, bio-researchers and eventually clinicians aimed at supporting both basic cancer quantitative research and individualized optimization of cancer treatment. This ‘Transatlantic’ project will therefore be the starting point for an international validation environment which will support joint applications, verification and validation of the clinical relevance of cancer models. To ensure the clinical relevance of this joint effort, the development of the project will be based upon specific clinical scenarios that will be implemented within an integrated EU-US workflow environment prototype for predictive, In Silico Oncology-guided clinical studies that will be deployed towards the end of the project. As an end result, a specific, clinically relevant workflow involving both EU and CViT models will be demonstrated, which will clearly highlight the need for and added value of interoperability. To achieve these goals, multiscale models/tools developed and data collected within the framework of three ongoing EC funded research projects namely ACGT [Advancing Clinicogenomic Trials on Cancer], ContraCancrum [Clinically Oriented Cancer Multilevel Modeling] and the <A href="/projects/VPHNoE/index.html">VPH-NoE</A> [Virtual Physiological Human Network of Excellence], in conjunction with models and data from the NIH supported ICBP Program CViT.org will drive the development, optimization and validation of the integrated system. Thus, a new module of the VPH environment will emerge. Department of Computer Science, University of Oxford Projects All oucl-All-TUMOR Fri, 10 Feb 2012 02:23:47 GMT VERIWARE: From Software Verification to Everyware Verification http://www.cs.ox.ac.uk/projects/VERIWARE/ In the words of Adam Greenfield, “the age of ubiquitous computing is here: a computing without computers, where information processing has diffused into everyday life, and virtually disappeared from view”. Conventional hardware and software has evolved into ‘everyware’ – sensor-enabled electronic devices, virtually invisible and wirelessly connected – on which we increasingly often rely for everyday activities and access to services such as banking and healthcare. The key component of ‘everyware’ is software, embedded inside electronic gadgets and continuously interacting with its environment by means of sensors and actuators. Ubiquitous computing must deal with the challenges posed by the complex scenario of communities of ‘everyware’, in presence of environmental uncertainty and resource limitations, while at the same time aiming to meet high-level expectations of autonomous operation, predictability and robustness. This calls for the use of stochastic modelling, discrete and continuous dynamics, quantitative measures, and goal-driven approaches, which the emerging quantitative software verification is unable to address at present. The central premise of the VERIWARE project is that there is a need for a paradigm shift in verification to enable ‘everyware’ verification, which can be achieved through a model-based approach that admits discrete and continuous dynamics, the replacement of offline methods with online techniques such as machine learning, and the use of game-theoretic and planning techniques. The project will significantly advance quantitative probabilistic verification in new and previously unexplored directions. This will involve investigating the fundamental principles of ‘everyware’ verification, development of algorithms and prototype implementations, and experimenting with case studies.  Department of Computer Science, University of Oxford Projects All oucl-All-VERIWARE Fri, 10 Feb 2012 02:23:47 GMT DIADEM: Domain-centric Intelligent Automated Data Extraction Methodology http://www.cs.ox.ac.uk/projects/DIADEM/ Do you need to rent a new apartment? Or would you just like to find a restaurant in your area that serves "pasta al pesto" as today’s special? In either case, you would most likely start a web search. But keyword search is not really appropriate in such cases, because you risk being swamped with irrelevant information, rather than finding what you want. If all the information were available in structured form, you could find what you are looking for much faster. Search engine providers such as Google, Yahoo! and Microsoft are aware of this, and are keenly looking for new methods that automatically recognize and extract data from domain-specific websites with semi-structured content. To this date, this problem has not been satisfactorily solved; its solution seems to require a major research breakthrough. In this project we will tackle precisely this challenge. Our goal is very ambitious. We want to develop domainspecific data extraction systems that take as input a URL of a website in a particular application domain, automatically explore the web site, and deliver as output a structured data set containing all the relevant information present on that site. We will provide the logical, algorithmic, and methodological foundations for the knowledge-based extraction of structured data from web sites belonging to specific domains, and we will develop two extraction systems for two different domains. To achieve our goal, we will design new methods and algorithms that combine database techniques with methods of knowledge representation and reasoning and web data extraction techniques. The breakthrough in automatic data extraction, which we are striving for, would enable a leap forward for two interrelated technologies which are the hottest emerging topics in web search: vertical search, that is, web search in specialized domains, and object search, that is, the search for web data objects rather than web pages. For more details and results see the <a href="http://diadem-project.info/">DIADEM homepage</a>.  Department of Computer Science, University of Oxford Projects All oucl-All-DIADEM Fri, 10 Feb 2012 02:23:47 GMT Hospital of the Future: Integrated Patient Management in the Digital Hospital http://www.cs.ox.ac.uk/projects/hotf/ Preventable deaths occur regularly in hospitals as a result of the failure to identify patient deterioration early enough. In August 2007, the National Patient Safety Agency (NPSA) issued a report on in-hospital deaths identifying the two most important actions which could be taken to improve patient safety: identify patients who are deteriorating and act early; improve systems to resuscitate patients when they have cardiac arrests (a training and skills development issue).    There is increasing evidence that early detection of patient deterioration, followed by appropriate action, not only reduces preventable deaths but also reduces the numbers of cardiac arrests or unplanned admissions to the Intensive Care Unit (ICU). Reports in the literature suggest that failure to respond to patient deterioration promptly and appropriately leads to increased morbidity and mortality, increased requirement for intensive care and elevated costs. The growing evidence has led the National Institute for Health and Clinical Excellence (NICE) to issue a clinical guideline in July 2007 for the management of acutely ill patients in hospital, recommending that physiological track and trigger systems should be used to monitor all adult patients in acute hospital settings.   The likelihood of a successful outcome following patient deterioration increases if the deterioration is detected early, recognised as important, communicated to appropriate team members and care rapidly escalated. Each of the four links in this "chain of action" is characterised by variation and therefore from time to time will be prone to failure. A central objective of our Grand Challenge is to reduce the probability of failure in each of these links to an absolute minimum.   Our research over the last decade has shown that the integration of continuously-monitored parameters using data fusion can provide early warning of adverse events. The data fusion systems are based on a probabilistic model of normality previously learnt from datasets of vital signs acquired from representative groups of high-risk patients. The system alerts the nursing staff whenever the combination of vital sign parameters is indicative of physiological abnormality.   The overall aim of the Grand Challenge is to develop a novel, flexible and integrated model of in-hospital patient care, which brings together at the point of care disparate sources of information over multiple time scales. High-quality, real-time vital sign data fused with information such as the medication record (today) or genomic data (in the long term) will allow the accurate tracking of a patient's recovery after, for example, hip surgery, stroke or myocardial infarction. This will improve patient safety, reduce unplanned admissions to higher levels of care and deliver care more efficiently, and will be achieved by integrating data fusion techniques with new features of the digital hospital - the Electronic Health Record (EHR) and full connectivity using wireless broadband. It will allow resources to be targeted at the identification of early deterioration and the prevention of irreversible decline in physiological status. This will deliver not only improved patient outcomes (reduction in preventable deaths, cardiac arrests and unplanned admission to intensive care) but also essential economic benefits: reduced length of stay and fewer unplanned admissions to (more expensive) higher levels of care.   The new, information-driven, integrated model of in-hospital patient care could be deployed throughout the NHS within the next 5 to 10 years. It is planned that the ICT solutions at the core of the research programme will be developed and validated in two hospitals (John Radcliffe Hospital in Oxford and Guy's & St Thomas' in London) within a 3-year timescale. Department of Computer Science, University of Oxford Projects All oucl-All-hotf Fri, 10 Feb 2012 02:23:47 GMT Computer to Clinic: Personalised Fluid-Mechanical Models Applied to Heart Failure http://www.cs.ox.ac.uk/projects/ComputertoClinic/ Heart Failure (HF) is defined by the heart's reduced ability to pump blood due to a drop in cellular contractility, enlarged anatomy and increased coronary micro-vascular resistance. This loss of pump function accounts for a significant increase in both mortality and morbidity in western society. With the U.K.'s elderly population expanding, HF is rapidly becoming an epidemic. There is currently a 1 in 5 life-time risk of HF and costs associated with acute and long term hospital treatments are accelerating. The significance of the disease has motivated the application of state of the art clinical imaging techniques to aid diagnosis and clinical planning. Measurements of cardiac wall motion, chamber flow patterns and coronary perfusion currently provide high resolution data sets for characterising HF patients. However, the clinical practice of using population-based metrics derived from separate image sets often indicates contradictory treatments plans due to inter-individual variability in pathophysiology. Thus, despite imaging advances, determining optimal treatment strategies for HF patients remains problematic. To exploit the full value of imaging technologies, and the combined information content they produce, requires the ability to integrate multiple types of functional data into a consistent framework. This in turn will support a paradigm shift away from predefined clinical indices determining treatment options and a move towards true personalisation of care based on an individual's physiology. An exciting and highly promising strategy for underpinning this shift is the assimilation of multiple image sets into personalised and biophysically consistent mathematical models. The development of such models provides the ability to capture the multi-factorial cause and effect relationships which link the underlying pathophysiological mechanisms. Furthermore, using a biophysical basis presents unique opportunities to assist with treatment decisions through the derivation of quantities that cannot be imaged but are likely to play a key mechanistic role in HF e.g. tissue stress and pump efficiency. In parallel with imaging advances the approach is also underpinned by the ongoing development of complementary technologies, including improved numerical methods and increased performance per unit cost of computing. This computational progress has accelerated the addition of multi-physics functionality to a range of organ models which have recently been organized into international initiatives such as the IUPS sponsored Physiome and VPH projects. Within these programmes the heart is arguably the most advanced current exemplar of an integrated organ model. As such it represents a promising first candidate with which to focus on an important human disease. My goal during this fellowship will be to focus on personalising and applying these models in clinical and industrial settings for treating HF patients. Model simulations will be focused on quantifying diagnosis, aiding patient selection and guiding interventional planning for specific treatments carried out by leading clinicians based in the cardio-vascular imaging group at Kings College London (KCL). In addition to this direct clinical application of the model, the research will also be focused on the tuning of Left Ventricular Assist Devices (LVADs) which are often connected to the heart in HF to reduce mechanical load by pumping blood from the left ventricle directly into the aorta. Through these applications my aim is to both improve our understanding of this significant cardiovascular disease and demonstrate the potential of biophysical models for improving human healthcare. Department of Computer Science, University of Oxford Projects All oucl-All-Computer to Clinic Fri, 10 Feb 2012 02:23:47 GMT Verification of Shared-Memory Concurrent Software http://www.cs.ox.ac.uk/projects/VerificationofShared-MemoryConcurrentSoftware/ <div>The goal of this project is to develop algorithms and tools for automated formal verification of low-level C programs that make use of shared-variable concurrency.  In spite of extensive research on concurrent computation, almost all existing program analysis tools are limited to sequential programs or programs that communicate via some form of explicit message passing. However, shared-variable concurrency is the predominant form of concurrency in commercial environments, and tool support is in dire need. The project focuses on</div><div><ol><li>verification by means of automated summarisation of threads,</li><li>identification of transactions, enabling partial-order reductions, and</li><li>Craig interpolation to derive thread invariants.</li></ol></div><div> </div> Department of Computer Science, University of Oxford Projects All oucl-All-Verification of Shared-Memory Concurrent Software Fri, 10 Feb 2012 02:23:47 GMT European Robotic Pedestrian Assistant http://www.cs.ox.ac.uk/projects/Europa/ EUROPA - European Robotic Pedestrian Assistant is a project funded by the European Commission within FP7. The goal of the EUROPA project is to develop the foundations for service robots designed to autonomously navigate in urban environments outdoors as well as in shopping malls and shops to provide various services to users including guidance, delivery, and transportation. Department of Computer Science, University of Oxford Projects All oucl-All-Europa Fri, 10 Feb 2012 02:23:47 GMT Quantitative Verification: From Model Checking to Model Measuring http://www.cs.ox.ac.uk/projects/QuantitativeVerification/ Enabling engineers, programmers, and researchers to automatically verify the correctness of the computer systems that they design is one of the Grand Challenges of computing research. The scientific and economic importance of this goal has long been recognised, yet, despite substantial progress in basic and applied research over the last few decades, much work remains ahead of us. With this Fellowship I would like to address the issue of quantitative verification and analysis of real-time and probabilistic systems, from the development of novel and fundamental algorithms all the way to the design and implementation of tools. The field of computer-aided formal verification is concerned, broadly speaking, with ensuring that computer systems function as they were intended to. In any instances, the correctness of such systems is critical, with failures potentially incurring disastrous financial consequences or even loss of human life. Well-known catastrophic failures in recent years include the 1996 explosion of the Ariane 5 rocket on its maiden flight, the 1999 loss of the MarsPolarLander as it attempted touch-down, and the 2003 Northeast power blackout, costing several billion dollars. In each case, the culprit was a bug in the software, which investigators subsequently discovered could have been rooted out by using computer-aided verification technology. One of the key approaches to verification is model checking, pioneered nearly three decades ago by Clarke, Emerson, Queille, Sifakis, and Pnueli, for which Clarke, Emerson, and Sifakis won the 2007 Turing Award and Pnueli the 1996 Turing Award. In this framework, a finite-state model of the system under consideration is constructed, usually in an automated or semi-automated manner, and its specifications are expressed using formulas in a suitable temporal logic. Model checking then involves determining whether the model satisfies the formulas, which is achieved using a sophisticated mix of abstraction techniques, symbolic representations, and graph-theoretic algorithms. The fundamental challenge in this approach is the state space explosion problem, whereby the state space of the systems to be explored can easily turn out to be astronomical. Model checking has nonetheless proved hugely valuable to the hardware industry, and more recently has become increasingly successful in software development. Industrial users of model checking include Intel, Motorola, Microsoft, Airbus, NASA, and many others. While traditional model checking has focussed on qualitative representations and properties of systems, there is an urgent need for quantitative verification technology, and specifically for frameworks able to accurately handle real-time and probabilistic systems. Such systems are ubiquitous, occurring in cars, aeroplanes, railway controllers, power plants, medical equipment, the Internet, etc. Research in quantitative verification has made great strides over the last two decades, yet many fundamental challenges remain. Building on recent breakthroughs in real-time and probabilistic model checking, I believe we are now ideally poised to tackle many of these challenges. Department of Computer Science, University of Oxford Projects All oucl-All-Quantitative Verification Fri, 10 Feb 2012 02:23:47 GMT Model Checking Timed Systems with Restricted Resources: Algorithms and Complexity http://www.cs.ox.ac.uk/projects/ModelChecking/ Computer software and hardware systems are among the most complex artifacts created by humans, thus it is not surprising that they often suffer costly or catastrophic failures due to errors in design. In 2002 a study by the US National Institute of Standard and Technology estimated that software failures alone cost the US economy 60 billion dollars per year. Against this background it is increasingly recognized that model checking - an approach to formally verifying the correctness of software and hardware systems - has an important role to play in meeting the challenge of producing correctly functioning systems. Intel, Lucent, Microsoft, Motorola, and NASA, among many others, already use model checking as part of their quality assurance process.In a nutshell, model checking involves constructing a mathematical model of a given system and then checking, automatically or semi-automatically, that the model meets a given formal specification. One of the main challenges of this task is the so-called state explosion problem. For example, a 10 megabyte cache has 10^(20,000,000) states. The challenge presented by the state explosion problem has spurred the development of a rich body of techniques, incorporating ideas from automata theory, artificial intelligence, combinatorial optimization, game theory, graph theory and mathematical logic. In 2007 Clarke, Emerson and Sifakis were awarded a Turing award (the Computer Science equivalent of a Noble prize) for their pioneering work in model checking. In this project we are concerned in particular with real-time systems, such as hardware, controllers and embedded systems. The correctness or acceptability of such systems can depend on real-time constraints, e.g., the response time of an anti-lock braking system or the latency in video transmission. The state explosion problem is particularly acute for real-time systems - indeed they are essentially infinite-state systems. As a consequence, in real-time model checking one must take great care in designing the modelling and specification formalisms. Apparently minor variations in these can lead to drastic changes in the tractability of model checking. The aim of this project is to identify modelling and specification formalisms that can express the type of system requirements described above, that also permit model checking algorithms that have reasonable complexity. An important outcome of this project will be algorithms and tools for model checking real-time systems. Such algorithms will employ novel combinatorial and automata-theoretic ideas, and will use symbolic techniques to permit exhaustive search of infinite state spaces. Another outcome of this project will be to enhance understanding of the use of temporal logics for reasoning about real-time behaviours, building on the highly successful use of temporal logics for discrete-time systems. Department of Computer Science, University of Oxford Projects All oucl-All-Model Checking Fri, 10 Feb 2012 02:23:47 GMT Virtual Physiological Human Network of Excellence http://www.cs.ox.ac.uk/projects/VPHNoE/ <img src="http://www.vph-noe.eu/images/stories/images/3_rs.jpg" alt="Illustration" title="VPH-NoE Illustration" width="207" height="207" />The Virtual Physiological Human Network of Excellence (VPH NoE) has been designed with 'service to the community' of VPH researchers as its primary purpose. Its aims range from the development of a VPH ToolKit and associated infrastructural resources, through integration of models and data across the various relevant levels of physiological structure and functional organisation, to VPH community building and support. The VPH NoE aims to foster the development of new and sustainable educational, training and career structures for those involved in VPH related science, technology and medicine. The VPH NoE constitutes a leading group of universities, institutes and organisations who will, by integrating their experience and ongoing activities in VPH research, promote the creation of an environment that actively supports and nurtures interdisciplinary research, education, training and strategic development. The VPH NoE will lead the coordination of diverse activities within the <a href="http://www.vph-noe.eu/background" target="_blank">VPH Initiative</a> to help deliver: new environments for predictive, patient-specific, evidence-based, more effective and safer healthcare; improved semantic interoperability of biomedical information and contribution to a common health information infrastructure; facile, on-demand access to distributed European computational infrastructure to support clinical decision making; and increased European multidisciplinary research excellence in biomedical informatics and molecular medicine by fostering closer cooperation between ICT, medical device, medical imaging, pharmaceutical and biotech companies. The VPH NoE will connect the diverse <a href="http://www.vph-noe.eu/vph-projects" target="_blank">VPH Initiative projects</a>, including not only those funded as part of the VPH initiative but also those of previous EC frameworks and national funding schemes, together with industry, healthcare providers, and international organisations, thereby ensuring that these impacts will be realised. <h3>VPH NoE work packages and project structure</h3> The VPH NoE activities are divided between five main work packages. In brief, the focus of each work package is as follows: <ul><li>Work package 1: Network Management</li><li>Work package 2: VPH NoE Exemplar Projects</li><li>Work package 3: VPH NoE ToolKit development</li><li>Work package 4: VPH NoE Training and Career Development</li><li>Work package 5: Spreading Excellence within the VPH NoE and VPH-I</li></ul> Department of Computer Science, University of Oxford Projects All oucl-All-VPH NoE Fri, 10 Feb 2012 02:23:47 GMT Advanced Formal Verification Techniques for Heterogeneous Multi-core Programming http://www.cs.ox.ac.uk/projects/AdvancedFormalVerificationTechniques/ Heterogeneous multi-core processors are key to complex computational problems such as real-time medical imaging, financial analysis and high-definition video, because of the increased processing power they make available. The reliability and probity of such applications is of critical importance, yet heterogeneous multi-core processors are notoriously difficult to program correctly. There is a need for analysis and verification techniques to help detect and fix errors early in the design of multi-core software. The development of such techniques is the aim of the proposed Fellowship research. The research will involve extending the capabilities of existing theoretical computer science techniques based on typechecking and model checking. Typechecking is a commonly used lightweight method for eliminating errors in computer programs: a basic typechecker will reject an invalid expression such as "Hello" + 1. More complex typechecking, based on "session types", can allow a protocol between two parties in a system to be automatically checked. One part of the Fellowship research will involve extending the notion of session types to be applicable to heterogeneous multi-core processors. New typechecking methods will also be developed to help programmers deal with complex issues arising from the management of separate memory spaces in multi-core systems. Model checking is a technique for verifying hardware and software systems which attempts to find system bugs by checking an abstract model of the system. Model checking is less widely used than typechecking, but model checking techniques have recently been incorporated in software products from major vendors such as Microsoft. A major part of the fellowship research will involve developing advanced model checking techniques to help find errors associated with the dynamic behaviour of software for heterogeneous multi-core processors. Part of the research will involve developing a set of open-source tools based on the novel formal analysis techniques. Experience has shown that developers interested in multi-core programming are reluctant to adopt new languages and formalisms, and will only consider new techniques if they are easy and intuitive to use, and can be integrated into an existing development tool-chain. To increase the potential for eventual adoption by industry, the new techniques developed during the Fellowship research will involve regular input and advice from Codeplay Software Ltd., a UK based company specialising in development tools for multi-core processors. Department of Computer Science, University of Oxford Projects All oucl-All-Advanced Formal Verification Techniques Fri, 10 Feb 2012 02:23:47 GMT FOX: Foundations of XML - Safe Processing of Dynamic Data over the Internet http://www.cs.ox.ac.uk/projects/FOX/ Official FOX Web page with publications is here: <A href="http://www.fox7.eu/">http://www.fox7.eu/</A> Department of Computer Science, University of Oxford Projects All oucl-All-FOX Fri, 10 Feb 2012 02:23:47 GMT Constraint Satisfaction for Configuration: Logical Fundamentals, Algorithms, and Complexity http://www.cs.ox.ac.uk/projects/ConstraintSatisfaction/ The project deals with configuration problems. Flexibility and efficiency in the customization of products and services - rather than series production - has become a key factor of competitiveness in the post-industrial economy. Configuration development is an excellent application area for artificial intelligence methods and for constraint satisfaction, in particular. Developing a product configuration system is a challenging task in many ways. Product configuration tools should be designed to encode the complex knowledge from domain experts, such as the characteristics of the different components involved in the ustomization and the restriction on how these components can be combined with each other. However, this might be very difficult in general, because customization is a generative process, where both the number of the involved components and the types of components themselves may be unknown at the beginning. The second challenge in building automatic configurators concerns the efficiency of the algorithms supporting the customization. In fact, product configuration in real scenarios is likely to involve several components and hundreds of associated variables, whose alues have to be dynamically determined based on the customer's needs. For instance, telephone switching systems often consisting of several hundreds of racks, thousands of frames, and dozens of thousands modules. Given the huge size of the problems to be reated, a major requirement is to integrate efficient algorithms to both building the configuration that best matches with the customer's desires and checking whether a given configuration satisfies the technological requirements from the industry. In order to achieve significant progress, we will first study existing approaches and compare them formally and request feedback from the industrial advisory board. We propose to investigate a formalism suited to the cope with the above mentioned challenges, called the extensible constraint satisfaction problem (ECSP). We ill study the expressive power and the complexity of decision and computational problems related to this formalism. We also propose to investigate the complexity issues in the presence of value-generating constraints, which is a well-known type of onstraints used in database theory, but has not been investigated in the context of CSPs so far. Once the framework for extensible CSPs has been layed out, our plan is to investigate decomposition techniques, to find tractable subclasses of ECSPs. Finally, we will implement and test a configurator system, based on our framework, nd using our decomposition algorithms. The project is organised into four main work packages. WP1 systematically studies the relevant problems to configuration, both by formally comparing existing approaches in the literature and by receiving feedback from the industrial advisory board. WP2 focuses n the extensible constraint satisfaction problems (ECSPs). Particular focus will be given to complexity analysis of the relevant decision and computational problems. WP3 consists of a comprehensive study of decomposition methods suitable to ECSPs to dentify tractable subclasses. In WP4, we will implement and test a proof-of-concept prototype of configuration system, based on ECSP and on the decomposition methods developed in WP3. The scientific project staff will consist of one post-doc, and one doctoral student. The student is expected to intensively co-operate with the post-doc. We plan to publish the results in top artificial intelligence journals and at leading international conferences. Department of Computer Science, University of Oxford Projects All oucl-All-Constraint Satisfaction Fri, 10 Feb 2012 02:23:47 GMT CONNECT-IP: Emergent Connectors for Eternal Software Intensive Networked Systems http://www.cs.ox.ac.uk/projects/CONNECT-IP/ The CONNECT-IP project is centred on a revolutionary concept of a seamless networking infrastructure for digital systems that enables continuous composition of networked systems and the evolution of their functionalities. This will be achieved through the application of formal reasoning, learning, and run-time synthesis of architectural connectors. The overall aim is to develop the principles and foundations for the architectural design, modelling and reasoning about networked systems. The Oxford component is led by Professor Marta Kwiatkowska and the contribution will focus on the formal foundations for connectors and automated quantitative verification techniques for non-functional requirements such as dependability. Department of Computer Science, University of Oxford Projects All oucl-All-CONNECT-IP Fri, 10 Feb 2012 02:23:47 GMT Models and technologies for assured, context-sensitive access control http://www.cs.ox.ac.uk/projects/contextsensitiveaccesscontrol/ As increasing amounts of data is collected about individuals, and, as the uses of such data become evermore imaginative, clear drivers are emerging both for novel models of authorisation that go 'beyond the norm' and for the provision of assurance that, when data is accessed, it is done so appropriately.  In this project we are concerned with the development of a model of authorisation that enables policies to evolve on the basis of changes within the environment in which the system is deployed.  The approach, termed evolving access control, has been developed initially with the needs of healthcare applications in mind, but it is applicable in many other contexts.  The origins of the work reside within the GIMI project. Department of Computer Science, University of Oxford Projects All oucl-All-contextsensitiveaccesscontrol Fri, 10 Feb 2012 02:23:47 GMT GAMES: Games for Design and Verification http://www.cs.ox.ac.uk/projects/GAMES/ As computing systems become larger, more complex, and increasingly distributed and interactive, there is a pressing need for formal methods that guarantee their reliability, correctness, and efficiency. This network proposes a research and training programme for the design and verification of computing systems, using a methodological framework that is based on the interplay of finite and infinite games, mathematical logic and automata theory. Department of Computer Science, University of Oxford Projects All oucl-All-GAMES Fri, 10 Feb 2012 02:23:47 GMT Reusability and Dependent Types http://www.cs.ox.ac.uk/projects/rdtp/ Robin Milner coined the slogan "well typed programs cannot go wrong", advertising the strength of typed functional languages like ML and Haskell in using types to catch runtime errors. Nowadays, we can and want to go further: dependently typed programming exploits the power of very expressive type systems to deliver stronger guarantees but also additional support for software development, using types to guide the development process. This is witnessed by a recent surge of language proposals with the goal to harness the power of dependent types, e.g. Haskell with GADTs, Agda, Coq, Omega, Concoqtion, Guru, Ynot, Epigram and so on. However, expressive type systems have their price: more specific types frequently reduce the reusability of code, whose too-specific implementation type may not fit its current application. This phenomenon already shows up in the traditional Hindley-Milner style type system of ML and Haskell; it becomes even more prevalent in a dependently typed setting. Luckily, all is not lost: dependent types are expressive enough that they can talk about themselves reflectively, making meta-programming one of its potential killer applications with the potential of combining expressive types and reusable software components. Based on and inspired by recent research at Nottingham on dependently typed programming (EPSRC <A href="http://gow.epsrc.ac.uk/ViewGrant.aspx?GrantRef=EP/C512022/1">EP/C512022/1</A>) and container types (EPSRC <A href="http://gow.epsrc.ac.uk/ViewGrant.ASPx?Grant=EP/C511964/1">EP/C511964/2</A>) and at Oxford on datatype-generic programming (EPSRC <A href="/projects/dgp/">GR/S27078/01</A>, <A href="/projects/gip/">EP/E02128X/1</A>) we plan to explore the potential of dependent types to deliver reusable and reliable software components. To achieve this, we intend to explore two alternative roads—reusability by structure and reusability by design—and express both within a dependently typed framework. Our programme is to build new tools extending the Epigram 2 framework, investigate the underlying theory using container types, and most importantly establish novel programming patterns and libraries. Department of Computer Science, University of Oxford Projects All oucl-All-rdtp Fri, 10 Feb 2012 02:23:47 GMT Acoustic Actuated Sensor Networks for Industrial Processes (AASN4IP) http://www.cs.ox.ac.uk/projects/AASN4IP/ The aim of this project is to develop an underwater mobile sensor network for exploring and monitoring enclosed and cluttered underwater environments like nuclear waste storage ponds. Nuclear power provides a significant portion of our energy demands and is likely to become more wide spread with the growing world population. However, the radioactive waste generated in these power plants must be held for 60-100 years underwater in a storage pool in large metal containers. These underwater environments must be carefully monitored and controlled to avoid an environmental catastrophe. Further details on the motivation and aims of our project can be found  <a href="/publications/publication3438-abstract.html">here</a>. In addition to the nuclear waste storage, there is a wide range of applications that can also benefit from our underwater mobile sensor network. One of these applications is industrial scale chemical process monitoring. Generally the chemical reactions are carried out in large reaction vessels and the chemical engineers are interested in monitoring the conditions inside the reaction vessel. Our small scale mobile sensor nodes can be introduced in such vessels to provide in situ monitoring. Another interesting application is the monitoring of a network of water reservoirs and pipes in a waste water treatment plant. The mobile sensor nodes that we envisage for these tasks are much smaller in size as compared to the traditional underwater vehicles. Our mobile sensor nodes are just 10cm in diameter and have full six degrees of freedom. This allows them to easily move in a cluttered environment. These robots are not only equipped with various sensors to sense the environment but also have ultrasound transducers for inter-node communication and range measurements. The following photograph shows one of the prototypes of our mobile sensor node.   <table border="0" cellspacing="2" align="center"> <tbody> <tr> <td><img src="P1010528_scaled.JPG" alt="Robot Prototype" align="middle" /> </td> <td><img src="P1010533_scaled.JPG" alt="Robot Prototype" align="middle" /> </td> </tr> </tbody> </table> <div> <table border="0" align="center"> <tbody> <tr> <td>  Robot Prototype (Photos from Simon Watson, University of Manchester) </td> </tr> </tbody> </table> </div>   For the robots to sense and explore the storage pools, they must be  able to determine their positions in these underwater environments.  However, the cluttered nature of our application scenarios presents us  with unique challenges. The ultrasound pulses used for performing  range measurements can reflect and bounce off multiple surfaces before  arriving at the the transducer. These multipath reflections introduce  large positive errors in some of the estimated distances between the  sensor nodes. These erroneous measurements make it very difficult to  estimate the true positions of sensor nodes. As part of the AASN4IP  project, we have developed two different approaches for solve these  problems. Our first approach involves a single-hop scenario where the mobile  sensor nodes perform range measurements to fixed reference points or  anchor nodes. These are high powered ultrasound transducers attached  to the pool infrastructure or vessel walls at known coordinates. The  mobile sensor nodes use the range measurements to these anchor nodes  and their coordinates to estimate their own coordinates. Since some of  these range measurements are erroneous, the traditional approaches  that employ the least squares technique fail to provide an accurate  position estimate when all the measurements are used to estimate node  coordinates. We propose an algorithm based on minimizing the sum of  absolute values of the residuals for these scenarios and show with  real experiments that it performs significantly better than the  traditional approaches. Our algorithm is independent of the underlying  physical layer used to perform range measurements and thus can be used  with any of the newer radio technologies e.g. UWB as well.  <a href="/publications/publication3717-abstract.html"> Please see  our publication for further details of this work </a> . Our second approach involves a multi-hop scenario where  special-purpose nodes, called 'localizers', are deployed in cluttered  NLOS-prone environments to help localize sensor nodes performing the  monitoring task. We investigate the performance of distributed  localization techniques, such as iterative localization and  DV-Distance, in cluttered environments, and explore a variety of  scenarios in which they outperform one-hop localization. The key  observation from our initial study is that the accuracy of distributed  localization techniques largely depends on the placement of  localizers. This advocates the need for careful placement of  localizers in a cluttered environment to minimize localization error.  In our initial work, we have focused on DV-Distance, and proposed an  algorithm that carefully selects where localizers should be placed to  reduce the localization error of DV-Distance. Our proposed algorithms  is centralized, it assumes knowledge of the clutter topology, and does  not deal with the practical problem of actually moving the localizers  to their selected positions. In order to address these problems, we  are currently working on distributed algorithms that enable a swarm of  localizers to coordinate with each other and self-deploy to provide a  high-accuracy localization service for the sensor nodes.  <a href="/publications/publication3688-abstract.html"> Please see  our publication for further details of this work </a> .    Department of Computer Science, University of Oxford Projects All oucl-All-AASN4IP Fri, 10 Feb 2012 02:23:47 GMT Sensing, Unmanned, Autonomous Aerial VEhicles http://www.cs.ox.ac.uk/projects/SUAAVE/ <LINK REL="SHORTCUT ICON" HREF="/people/Sonia.Waharte/images/suaave.ico"/> <IMG width="271" height="192" align="right" title="SUAAVE Quadrotor UAV" alt="UAV" src="/people/Sonia.Waharte/images/uav.jpg">The focus of SUAAVE lies in the creation and control of swarms of helicopter UAVs (unmanned aerial vehicles) that are individually autonomous (i.e not under the direct realtime control of a human) but that collaboratively self-organise: to sense the environment in the most efficient way possible; to respond to node failures; and to report their findings to a base station on the ground. Such clouds (or swarms or flocks) of helicopters have a wide variety of applications in both civil and military domains since they are rapidly deployable and highly survivable. In effect there are three separate capabilities for use in addressing application-specific problems: (i) ground sensing of various types; (ii) atmospheric sampling; and (iii) the ability to bridge communications, all within a rapidly deployable, survivable, hands-off package. Examples of these include: search and rescue; pollution monitoring; chemical/biological/radiological weapons plume monitoring; disaster recovery - e.g. (flood) damage assessment; sniper location; communication bridging in ad hoc situations; and overflight of sensor fields for the purposes of collecting data. The novelty of these mobile sensor systems is that their movement is controlled by fully autonomous tasking algorithms with two important objectives: first, to increase sensing coverage to rapidly identify targets; and, second, to maintain network connectivity to enable real-time communication between UAVs and ground-based crews. The project has four main scientific themes: (i) wireless networking as applied in a controllable free-space transmission environment with three free directions in which UAVs can move; (ii) control theory as applied to aerial vehicles, with the intention of creating truly autonomous agents that can be tasked but do not need a man-in-the-loop control in real time to operate and communicate; (iii) artificial intelligence and optimisation theory as applied to a real search problem; (iv) data fusion from multiple, possibly heterogeneous airborne sensors as applied to construct and present accurate information to situation commanders. <DIV> <IMG width="357" height="240" align="right" title="UAV" alt="UAV" src="/people/Sonia.Waharte/images/uav_flying.jpg"> Research Interests </DIV> <UL> <LI>Multi-robot exploration under uncertainty </LI> </UL> When trying to determine the location of an object of interest, it is necessary to account for the partial information obtained from noisy measurements. Probability models can be derived to account for this uncertainty and consequently be used as input in the search strategy. Here are the videos taken from our UAV during some fields experiments. They have been used to assess how altitude affects the detection of a target. <TABLE width="100%" border="0"> <TBODY> <TR> <TD width="50%" valign="top" align="left"><script type='text/javascript' src='/includes/flashplayer/swfobject.js'></script> <div id='feature' align="center">You will need at least <A href='http://www.adobe.com/products/flashplayer/' target='_blank'>Adobe Flash 8</a> and Javascript enabled on your browser</div> <script type='text/javascript'> var s1 = new SWFObject('/includes/flashplayer/player.swf','player','320','260','9'); s1.addParam('allowfullscreen','true'); s1.addParam('allowscriptaccess','always'); s1.addParam('flashvars','file=http://www.cs.ox.ac.uk/people/sonia.waharte/videos/Bristol_icra_rawdata.m4v&autostart=false'); s1.write('feature'); </script> </TD> <TD width="50%" valign="top" align="left"><script type='text/javascript' src=/includes/flashplayer/swfobject.js'></script> <div id='feature1' align="center">You will need at least <A href='http://www.adobe.com/products/flashplayer/' target='_blank'>Adobe Flash 8</a> and Javascript enabled on your browser</div> <script type='text/javascript'> var s2 = new SWFObject('/includes/flashplayer/player.swf','player','320','260','9'); s2.addParam('allowfullscreen','true'); s2.addParam('allowscriptaccess','always'); s2.addParam('flashvars','file=http://www.cs.ox.ac.uk/people/sonia.waharte/videos/Bristol_icra_targdetect.m4v&autostart=false'); s2.write('feature1'); </script> </TD> </TR> </TBODY> </TABLE> <TABLE width="100%" border="0"> <TBODY> <TR> <TD width="50%" valign="top" align="center"> <DIV align="center"> <DIV align="center"> Field tests RVC 2009 - Video taken from our UAV. </DIV> </DIV> </TD> <TD width="50%" valign="top" align="center"> <DIV align="center"> <DIV align="center"> Field tests RVC 2009 - Target detection with our UAV. </DIV> </DIV> </TD> </TR> </TBODY> </TABLE> The presence of multiple agents can also be exploited with the implementation information sharing mechanisms. <UL> <LI>Connectivity-constrained multi-robot exploration</LI> </UL> In a network where each node acts in a self-interested manner, connectivity occurs opportunistically. However, by sharing information regularly nodes take into account more global information and are thus able to make more optimal control decisions. Essentially, it's a trade-off between sensing coverage and quality. The objective being to find and implement distributed methods of evaluating and preserving connectivity within a mobile sensor network. Our interest is to measure how this connectivity affects the performance of cooperative exploration by a team of autonomous UAVs. Department of Computer Science, University of Oxford Projects All oucl-All-SUAAVE Fri, 10 Feb 2012 02:23:47 GMT Cost-efficient methods and processes for safety relevant embedded systems http://www.cs.ox.ac.uk/projects/CESAR/ The embedded safety-critical systems design and development industry is facing increasing complexity and variety of systems and devices, coupled with increasing regulatory constraints while costs, performances and time to market are constantly challenged.   This has led to a profusion of enablers (new processes, methods and tools), which are neither integrated nor interoperable because they have been developed more or less independently, addressing only a part of the complexity issue, such as safety. The absence of internationally recognized open standards is a limiting factor in terms of industrial performance when companies have to select among these enablers.   CESAR will bring significant and conclusive innovations in the two most improvable systems engineering disciplines: - Requirements engineering in particular through formalization of multi viewpoint and multi criteria requirements, - Component based engineering applied to design space exploration comprising multi-view/multi-criteria architecture trade-offs. In addition CESAR intends to provide industrial companies with a breakthrough in system development by deploying a customizable systems engineering ‘Reference Technology Platform’ (RTP) making it possible to integrate or interoperate existing or emerging available technologies. This will be a significant step forward in terms of industrial performance improvement that will help to establish de-facto standards and contribute to the standardization effort from a European perspective.   Relying on industrial use-cases and scenarios, CESAR is strongly industry driven. It will address societal safety, mobility and environmental demands from a multi-domain point of view, relying on high maturity inputs (TRL 4) and target high maturity outputs (TRL 6).  Department of Computer Science, University of Oxford Projects All oucl-All-CESAR Fri, 10 Feb 2012 02:23:47 GMT Scalable Query Processing in Probabilistic Databases http://www.cs.ox.ac.uk/projects/SPROUT/ <IMG title="SPROUT logo" src="/people/Dan.Olteanu/sprout_logo-small.png" alt="SPROUT logo" align="left"> Today, uncertainty is commonplace in data management scenarios dealing with data integration, sensor readings, information extraction from unstructured sources, and whenever information is manually entered and therefore prone to inaccuracy or partiality. Key challenges in probabilistic data management are to design probabilistic database formalisms that can compactly represent large sets of possible interpretations of uncertain data together with their probability distributions, and to efficiently evaluate queries on very large probabilistic data. Such queries could ask for confidences in data patterns possibly in the presence of additional evidence. The problem of query evaluation in probabilistic databases is still in its infancy. Little is known about which queries can be evaluated in polynomial time, and the few existing evaluation methods employ expensive main-memory algorithms. The aim of this project is to develop techniques for scalable query processing in probabilistic databases and use them to build a robust query engine called SPROUT ( S calable PRO cessing on U ncertain T ables). We are currently exploring three main research directions. <UL> <LI>We are investigating open problems in efficient query evaluation. In particular, we aim at discovering classes of tractable (i.e., computable in polynomial time wrt data complexity) queries on probabilistic databases. The query language under investigation is SQL (and its formal core, relational algebra) extended with uncertainty-aware query constructs to create probabilistic data under various probabilistic data models (such as tuple-independent databases, block-independent disjoint databases, or U-relations of MayBMS). </LI> <LI>For the case of intractable queries, we investigate approximate query evaluation. In contrast to exact evaluation, which computes query answers together with their exact confidences, approximate evaluation computes the query answers with approximate confidences. We are working on new techniques for approximate query evaluation that are aware of the query and the input probabilistic database model (tuple-independent, block-independent disjoint, etc). </LI> <LI>Our open-source query engine for probabilistic data management systems uses the insights gained from the first two directions. This engine is based on efficient secondary-storage exact and approximate evaluation algorithms for arbitrary queries. </LI> </UL> <H3>News</H3> <UL> <LI>[Sept 2011] Larisa Han won the Hoare prize for the best MSc thesis in Computer Science at Oxford for her thesis on aggregates in probabilistic databases.</LI> </UL> <UL> <LI>[July 1] A news item about our work on probabilistic databases and the new book has been futured on <A href=" http://www.i-programmer.info/news/84-database/2653-probabilistic-databases-the-next-big-thing.html">i-programmer </A>. Thank you! </LI> </UL> <UL> <LI>[June 2, 2011] The first book on the foundations of <A href="http://www.morganclaypool.com/doi/abs/10.2200/S00362ED1V01Y201105DTM016">Probabilistic Databases</A> by Dan Suciu, Dan Olteanu, Christopher Re, and Christoph Koch has been published by Morgan & Claypool!</LI> </UL> <UL> <LI>[June 1, 2011] An article on probabilistic databases authored by Robert and Dan appeared in the 10th anniversary edition of <A href="http://www.thinkdigit.com/">The Digit Magazine</A>, the largest selling technology magazine in India, with a certified readership of 200,000.</LI> </UL> <UL> <LI>[June 1, 2011] An article featuring SPROUT has appeared in the second edition of Inspired Research, the industry letter of the Department of Computer Science at Oxford.</LI> </UL> <UL> <LI>[Oct 2010] Swaroop Rath's MSc thesis on the evaluation of full relational algebra queries was awarded distinction. His overall performance placed him second in the MSc in CS course.</LI> </UL> <UL> <LI>[Oct 2009] Rasmus Wissmann won the Hoare prize for the best overall performance in our MSc in Computer Science at Oxford. His thesis on "Tractable Queries with Inequalities on Probabilistic Databases" was also awarded distinction.</LI> </UL> <UL> <LI>[July 2009] Our SIGMOD'09 paper on tractable conjunctive queries with inequalities passed the SIGMOD'09 repeatability and workability evaluation (RWE). Out of 63 accepted papers, 19 participated in RWE, and 10 papers passed RWE.</LI> </UL> <UL> <LI>[May 2009] Jiewen Huang won a Travel Grant from ACM SIGMOD to attend SIGMOD 2009! Read more <A href="http://www.sigmod09.org/delegates_travel_grants.shtml">here</A> about the grant. </LI> </UL> <UL> <LI>[Sept 2008] Jiewen Huang won the Hoare prize for the best MSc thesis in Computer Science at Oxford. His thesis on "Scalable Query Evaluation for Tuple-Independent Probabilistic Databases" investigates aspects of this project and the results are reported in the SUM'08 and ICDE'09 papers. Jiewen also won the Hoare prize for the best overall performance in his MSc year at Oxford. </LI> </UL> <UL> <LI>[August 2008] SPROUT prototype released as part of the MayBMS database management system available at <A href="http://maybms.sourceforge.net/">maybms.sourceforge.net</A></LI> </UL> <H3>System prototype</H3> SPROUT is implemented as an extension of the PostgreSQL backend with secondary-storage and main-memory algorithms for exact or approximate confidence computation. The latest online version of SPROUT is available <A href="/people/dan.olteanu/code/ohk-icde10-sprout.tgz">here</A> (this is the version reported in the ICDE 2009 paper; newer versions are available on request). Major releases of SPROUT are also included in the MayBMS database management system available at <A href="http://maybms.sourceforge.net/">maybms.sourceforge.net</A>. <H3>Talks</H3> <UL> <LI>Aggregation in Probabilistic Databases Given by Robert in the Oxford Information Systems Seminar and at Dagstuhl Seminar on "Foundations of distributed data management". October 2011. </LI> </UL> <UL> <LI>The Case of Relational Algebra Queries in Probabilistic Databases Given by Dan at IC Colloquium, EPFL, January 2011, Lausanne.</LI> </UL> <UL> <LI>A Look at Probabilistic Databases through SPROUT glasses Given by Dan at the Statistics Departmental Seminar, November 2010, Oxford.</LI> </UL> <UL> <LI>SPROUT: Scalable Query Processing in Probabilistic Databases [Feb 2010 overview talk <A href="/people/Dan.Olteanu/tutorials/mound10-talk.pdf">PDF</A>, <A href="/people/Dan.Olteanu/tutorials/sprout-poster.pdf">A1 poster.pdf</A>] Given by Dan at various venues, 2008-2009. </LI> </UL> <UL> <LI>A Toolbox of Query Evaluation Techniques for Probabilistic Databases. [<A href="/people/dan.olteanu/tutorials/mound10-talk.pdf">PDF</A>] Invited talk at the Workshop on Logic in Databases (LID), October 2009. Invited talk at the Workshop on Management and mining Of UNcertain Data (MOUND), In conjunction with ICDE, March 2010. </LI> </UL> <UL> <LI>Incomplete and Probabilistic Data Management. 3-hour tutorial given at FOX training week, October 2009. </LI> </UL> <H3>Theses</H3> <UL> <LI>Larisa Han: Aggregates in Probabilistic Databases MSc in CS, Oxford 2011. </LI> </UL> <UL> <LI>Swaroop Rath: Efficient Evaluation of Full Relational Algebra on Probabilistic Databases MSc in CS, Oxford 2010. </LI> </UL> <UL> <LI>Jiewen Huang: Design and Implementation of the SPROUT Query Engine for Probabilistic Databases [<A href="/people/dan.olteanu/theses/Jiewen.Huang.pdf">PDF</A>] MSc by Research, Oxford 2009. </LI> </UL> <UL> <LI>Rasmus Wissmann: Tractable Queries with Inequalities on Probabilistic Databases [<A href="/people/dan.olteanu/theses/Rasmus.Wissmann.pdf">PDF</A>] MSc in CS, Oxford 2009. </LI> </UL> <UL> <LI><A title="data-collection" name="data-collection"></A>Smitha Mysore-Shankar: Learning Probabilistic Databases MSc in CS, Oxford 2009. Data collection: <A href="/people/dan.olteanu/theses/Smitha.Shankar.urls.zip">URLs</A> to web-pages used to extract data and populate probabilistic databases </LI> </UL> <UL> <LI>Jiewen Huang: Efficient Query Evaluation for Tuple-Independent Probabilistic Databases MSc in CS, Oxford 2008. Hoare prizes for best MSc in CS thesis and best overall MSc in CS performance at Oxford </LI> </UL> <H3>Publications</H3> <UL> <LI>Aggregates in Probabilistic Databases via Knowledge Compilation. Robert Fink, Larisa Han, and Dan Olteanu. To appear in Very Large Data Bases (VLDB), Istanbul, 2012. </LI> </UL> <UL> <LI>Ranking in Probabilistic Databases: Complexity and Efficient Algorithms. Dan Olteanu and Hongkai Wen. To appear in IEEE Int Conf on Data Engineering (ICDE), Washington DC, 2012. </LI> </UL> <UL> <LI> <A href="http://www.morganclaypool.com/doi/abs/10.2200/S00362ED1V01Y201105DTM016"> Probablistic Databases</A> Synthesis Lectures on Data Management, Morgan & Claypool, 2011, 180 pages. Dan Suciu, Dan Olteanu, Christopher Re, Christoph Koch. DOI: 10.2200/S00362ED1V01Y201105DTM016. </LI> </UL> <UL> <LI>The Next Big Challenge in Data Management: Probabilistic Databases. Robert Fink and Dan Olteanu. Invited article in <A href="http://www.thinkdigit.com/">The Digit Magazine</A>, June 2011 (10th Anniversary Special), in print. More about the Digit Magazine in <A href="http://en.wikipedia.org/wiki/Digit_(magazine)">Wikipedia</A>. </LI> </UL> <UL> <LI>Managing Probabilistic Data with SPROUT. Dan Olteanu. Article in the 2nd edition of Inspired Research published by the Department of Computer Science at the University of Oxford. June 2011. </LI> </UL> <UL> <LI>SPROUT^2: A Squared Query Engine for Uncertain Web Data (Demonstration). [<A href="/people/dan.olteanu/papers/for-sigmod11.pdf">pdf</A>, <A href="/people/dan.olteanu/papers/for-sigmod11-poster.pdf">poster</A>, <A href="/people/dan.olteanu/sprout2/">web page</A> ] Robert Fink, Andrew Hogue, Dan Olteanu, and Swaroop Rath. In Proc. of ACM SIGMOD, Athens, June 2011. </LI> </UL> <UL> <LI>Providing Support for Full Relational Algebra in Probabilistic Databases. [<A href="/people/dan.olteanu/papers/for-icde11.pdf">pdf</A>] Robert Fink, Dan Olteanu, and Swaroop Rath. In Proc. of IEEE Int Conf on Data Engineering (ICDE), Hannover, 2011. </LI> </UL> <UL> <LI>On the Optimal Approximation of Queries using Tractable Propositional Theories. [<A href="/people/dan.olteanu/papers/fo-icdt11.pdf">pdf</A>] Robert Fink and Dan Olteanu. In Proc. of Int Conf on Database Theory (ICDT), Uppsala, 2011. </LI> </UL> <UL> <LI>Bridging the Gap Between Intensional and Extensional Query Evaluation in Probabilistic Databases.[<A href="/people/dan.olteanu/papers/jos-edbt10.pdf">pdf</A>] Abhay Jha, Dan Olteanu, and Dan Suciu. In Int Conf on Extending Data Base Technology (EDBT), Lausanne, March 2010. We extend the notion of tractable queries on (arbitrarily correlated) probabilistic databases to tractable data-query instances, where general hard queries can become tractable on restricted data instances. The query evaluation is separated into two steps: (1) the (possibly large) tractable data-query instance is evaluated first by efficient database techniques, and then (2) the (usually small) intractable residue is processed using inference techniques based on treewidth. </LI> </UL> <UL> <LI>Approximate Confidence Computation in Probabilistic Databases. [<A href="/people/dan.olteanu/papers/ohk-icde10.pdf">pdf</A>] Dan Olteanu, Jiewen Huang, and Christoph Koch. In Proc. of IEEE Int Conf on Data Engineering (ICDE), Long Beach, March 2010. We enhance our query engine <A href="/projects/SPROUT/">SPROUT</A> with a deterministic approximation algorithm with error guarantees for confidence computation in (arbitrarily correlated) probabilistic databases, which is based on incremental compilation of query lineage into so-called decomposition trees that support linear-time probability computation. The compilation is incremental and we show experimentally that it can achieve a given approximation within a few steps. In case of tractable (hierarchial or inequality) queries, it always finishes in polynomial time. </LI> </UL> <UL> <LI>On Tractability of Inequality Queries over Probabilistic Databases and Counting Vertex Covers. Dan Olteanu and Rasmus Wissmann. technical report, September 2009. </LI> </UL> <UL> <LI>Secondary-Storage Confidence Computation for Conjunctive Queries with Inequalities. [<A href="/people/dan.olteanu/papers/oh-sigmod09.pdf">pdf</A>] Dan Olteanu, Jiewen Huang. In Proc. of ACM Special Interest Group on Management of Data (SIGMOD), Providence, 2009. This paper is the first to discuss tractability of conjunctive queries with inequalities in probabilistic databases. It presents a class of hard queries, and gives a scalable algorithm for tractable inequality queries that is based on ordered binary decision diagrams and is implemented in our query engine <A href="/projects/SPROUT/">SPROUT</A>. Our implementation passed the SIGMOD'09 repeatability and workability evaluation (RWE). Out of 63 accepted papers, 19 participated in RWE, and 10 passed RWE. Resources: <UL> <LI><A href="/people/dan.olteanu/code/oh-sigmod09-experiments.tgz">Scripts</A> for running the experiments. </LI> <LI><A href="/people/dan.olteanu/code/oh-sigmod09-sprout.tgz">Code</A> of the SPROUT query engine used in the experiments. </LI> </UL> </LI> </UL> <UL> <LI>SPROUT: Lazy vs. Eager Query Plans for Tuple-Independent Probabilistic Databases. [<A href="/people/dan.olteanu/papers/ohk-icde09.pdf">pdf</A>] Dan Olteanu, Jiewen Huang, Christoph Koch. In Proc. of IEEE Int Conf on Data Engineering (ICDE), Shanghai, April 2009. We show that the tractable hierarchical queries on probabilistic databases admit relational query plans with unrestricted join ordering, thereby overcoming the limitations of the safe plans of earlier work. In this framework, safe plans can be seen as one specific type of eager plans (where confidence computation is done as soon as possible). We extend relational plans with a new aggregation operator that is optimized using query signature and schema information (keys) to minimize the number of scans it needs to compute tuple confidences. This operator basically factorizes the query lineage into read-once functions (called 1OF formulas in the paper) in polynomial time. An extensive study on TPC-H queries is available <A href="papers/icde09queries.html">here</A>. Resources: <UL> <LI><A href="/people/dan.olteanu/papers/icde09queries.html">Case study</A>: Tractable TPC-H queries on probabilistic databases. </LI> <LI><A href="/people/dan.olteanu/tutorials/sprout.pdf">One-hour talk on the results of this paper</A>. </LI> <LI><A href="/people/dan.olteanu/code/ohk-icde10-sprout.tgz">Current version</A> of the SPROUT query engine. </LI> </UL> </LI> </UL> <UL> <LI>Using OBDDs for Efficient Query Evaluation on Probabilistic Databases. [<A href="/people/dan.olteanu/papers/oh-sum08.pdf">pdf</A>] Dan Olteanu, Jiewen Huang. In Proc. of <A href="http://www.kr.tuwien.ac.at/staff/lukasiew/sum08/">2nd Int. Conf. on Scalable Uncertainty Management (SUM)</A>, Napoli, Oct. 2008. Also in Proc. of Dagstuhl <A href="http://kathrin.dagstuhl.de/08421/Materials/">seminar #08421 on uncertainty management</A>, October 2008. This paper is the first to consider OBDDs for efficient evaluation of queries in probabilistic databases. It shows that for tractable hierarchical queries, the query lineage can be efficiently brought into one-occurrence form (that is, into an equivalent read-once function), where each variable occurs exactly once. For hard queries, existing results that bound the OBDD size in the pathwidth of the lineage apply immediately. </LI> </UL> <UL> <LI>Conditioning Probabilistic Databases. [<A href="http://arxiv.org/abs/0803.2212">pdf</A>] Christoph Koch, Dan Olteanu. In Proc. of VLDB Endowment (PVLDB), volume 1, 2008. Also ACM CORR Report cs.DB/0803.2212. This paper is the first to consider the problem of conditioning a probabilistic database outside of the context of graphical models. The core contribution is an exact confidence computation algorithm and its extension to achieve conditioning. Resources: <UL> <LI><A href="/people/dan.olteanu/code/confidence-computation.tgz">CODE:</A> Exact and approximate probability computation using world-set trees (now part of MayBMS). </LI> <LI><A href="/people/dan.olteanu/tutorials/vldb08-talk.pdf">Talk</A> given at <A href="https://www.cs.auckland.ac.nz/research/conferences/vldb08/index.php/VLDB_08">34th Int. Conf. on Very Large Data Bases (VLDB)</A>, Auckland, Aug 2008. </LI> </UL> </LI> </UL> <H3>Current team</H3> <UL> <LI>Robert Fink</LI> <LI>Dan Olteanu</LI> </UL> Collaborators: Andrew Hogue (Google), Abhay Jha (U. of Washington), Christoph Koch (Cornell University, now at EPFL), Dan Suciu ((U. of Washington) Alumni: Larisa Han (MSc student), Jiewen Huang (research student), Smitha Mysore-Shankar (MSc student), Yunli Sung (MSc student), Rasmus Wissmann (MSc student), Swaroop Rath (MSc student), , Hongkai Wen (research student) <H3>Acknowledgments</H3> Starting May 2009, the SPROUT research project is partially supported by the Future and Emerging Technologies (FET) programme within the Seventh Framework Programme for Research of the European Commission, under the FETOpen grant agreement FOX, number FP7-ICT-233599. During the academic year 2008-2009, Jiewen Huang was generously supported by a scholarship from Cornell University. Department of Computer Science, University of Oxford Projects All oucl-All-SPROUT Fri, 10 Feb 2012 02:23:47 GMT Efficient Verification of Software with Replicated Components http://www.cs.ox.ac.uk/projects/Symmetry/ Concurrency is a model of computation that allows many units of execution to coexist. It is ubiquitous in computer science today: user processes in a time-sharing operating system execute concurrently, as do worker threads in client-server environment. Parallel processing, once primarily of interest in high-performance computing, has emerged in recent years as a new way of increasing processing power, such as in multi-core concurrent systems, even for the home personal computer.Concurrency poses new challenges for the quality assurance of software, for two reasons. First, concurrent programs have the potential for forms of errors unknown in sequential computation, such as race conditions and mutual exclusion violations. Second, traditional reliability measures such as simulation and testing fail in the presence of concurrency, due to the difficulties of reproducing erroneous behavior. Model Checking is an automated technique to reliably establish the correctness of software, or to reveal the existence of errors in a reproducible manner. A program is represented by a finite-state model, which is exhaustively searched for violations of pre-specified properties. Exhaustive search, however, generally incurs a cost proportional to the number of model states that are reached during the search. This number is in turn worst-case exponential in the number of concurrent components. This state space explosion problem has been a major obstacle to the widespread use of model checking. One avenue of our research is guided by the observation that concurrent ystems often consist of replicated components: instances of a single template, generically describing the behavior of each component. Concurrent systems of replicated components often exhibit a very regular - symmetric - structure: their behavior is invariant under interchanges of the components. This causes redundancy in the system model and in the (naive) exploration of the model's state space. We propose to investigate the efficacy of symmetry reduction and parameterized verification to attack the state space explosion problem for software with replicated components. Both techniques have shown to be tremendously effective in principle, namely due to their potential of reducing the size of a symmetric system by an exponential factor, or of collapsing the verification problem for an infinite family of systems to one for a single system or a small finite family, respectively. The applicability of these techniques to concurrent software was hampered, however, by the apparent incapability of model checking to deal with integer variables over very large domains or even unbounded, dynamic data structures. The situation changed dramatically with the advent of automated abstraction-refinement techniques. Software is initially represented abstractly using coarse finite-state models, risking the possibility of incorrect - spurious - verification results. The new paradigm came with ways of detecting spuriousness, and of dealing with it by iteratively refining the abstract model until spurious behavior is removed. To sum up, concurrent software exhibits two sources of complexity: large variable data domains and concurrency. Fortunately, these sources are orthogonal and can be attacked separately. This separation makes it possible to apply symmetry reduction and parameterized techniques to concurrent software, methods that target the concurrency aspect of state space explosion. The ultimate goal of the proposed work is to combine these methods with iterative abstraction refinement to obtain verification tools for concurrent software that can seriously curb state space explosion at all levels. Department of Computer Science, University of Oxford Projects All oucl-All-Symmetry Fri, 10 Feb 2012 02:23:47 GMT MayBMS: A Database Management System for Uncertain and Probabilistic Data http://www.cs.ox.ac.uk/projects/MayBMS/ <DIV> <IMG width="0" height="0" alt="MayBMS logo" src="/people/Dan.Olteanu/maybms_logo.jpg"> </DIV> Uncertain data arises often in practice. Examples include scientific databases, data integration, sensor data management, as well as scenarios where information is manually entered and is therefore prone to mistakes and incompleteness. MayBMS is a probabilistic database management system. Its main features include (among others) a powerful query language for processing and transforming uncertain data, space-efficient representation and storage, and support for data cleaning. Efficient query processing techniques for probabilistic databases, which are also integrated in MayBMS, form the subject of a more specific project called <A href="/projects/SPROUT/index.html">SPROUT</A>. <H3>News</H3> <UL> <LI>June 2, 2011: The first book on the foundations of <A href="http://www.morganclaypool.com/doi/abs/10.2200/S00362ED1V01Y201105DTM016">Probabilistic Databases</A> by Dan Suciu, Dan Olteanu, Christopher Re, and Christoph Koch has been published by Morgan & Claypool!</LI> <LI>May 2011: An article on probabilistic databases authored by Robert and Dan is due to appear next month in the 10th anniversary edition of <A href="http://www.thinkdigit.com/">The Digit Magazine</A>, the largest selling technology magazine in India, with a certified readership of 200,000.</LI> <LI>June 2009: MayBMS to be demonstrated at ACM SIGMOD 2009. See our demo paper <A href="/dan.olteanu/papers/hako-sigmod09.pdf"> MayBMS: A Probabilistic Database Management System </A> and <A href="/dan.olteanu/maybms.mp4">3-minute video</A>! </LI> <LI>March 2009: MayBMS 2.1 beta is released on <A href="http://maybms.sourceforge.net/">sourceforge</A>! </LI> <LI>April 2008: "Fast and Simple Relational Processing of Uncertain Data" by Antova, Jansen, Koch, and Olteanu is the runner-up to the best paper award at IEEE ICDE 2008! (full paper, acceptance rate for full papers: 12.1%) </LI> <LI>April 2008: "MayBMS: A System for Managing Large Uncertain and Probabilistic Databases" by Antova, Koch, and Olteanu wins First Prize in Poster Contest, Spring'08 DB/IR Day at Columbia University. </LI> </UL> <H3>Resources</H3> <UL> <LI>System, manual, worked-out examples, and publications are publicly available at <A href="http://maybms.sourceforge.net/">maybms.sourceforge.net</A>. </LI> </UL> <H3>Team</H3> MayBMS is a joint research project led by Professor Christoph Koch of EPFL. Dan Olteanu of the University of Oxford is co-Investigator. Oxford Alumni: Jiewen Huang (research student), Tibor Barna (3rd year student). Department of Computer Science, University of Oxford Projects All oucl-All-MayBMS Fri, 10 Feb 2012 02:23:47 GMT Integrative computational and experimental study of arrhythmogenesis and defibrillation in acute myocardial ischaemia http://www.cs.ox.ac.uk/projects/MRC07_BR/ Electrical defibrillation by timely application of a strong shock to the myocardium is the only effective therapy to prevent sudden cardiac death subsequent to ventricular fibrillation. However, although the majority of patients undergoing defibrillation suffer from coronary heart disease, little is known about the ischaemic tissue response to the delivery of defibrillation shocks. The main focus of the proposed research is to unravel the mechanisms underlying changes in defibrillation efficacy during the first 45 min of acute myocardial ischaemia. We expect to ultimately advance the development of new or improved anti-arrhythmia interventions with increased success rates of cardiac defibrillation, which could reduce mortality /morbidity from sudden cardiac death. Department of Computer Science, University of Oxford Projects All oucl-All-MRC07_BR Fri, 10 Feb 2012 02:23:47 GMT service-oriented interoperability framework http://www.cs.ox.ac.uk/projects/sif/ sif (service-oriented interoperability framework), which was developed within the GIMI project, facilitates the secure sharing of data across organisational boundaries. We are currently developing applications in conjunction with the Oxford Centre for Integrative Systems Biology, the Oxford Biomedical Research Centre, and the University Admissions Service and Academic Administration Service within Oxford. Department of Computer Science, University of Oxford Projects All oucl-All-sif Fri, 10 Feb 2012 02:23:47 GMT Predictable Software Systems http://www.cs.ox.ac.uk/projects/predictablesoftware/ The increasing complexity, scale and pervasive nature of software systems currently being deployed pose new challenges for software engineering. Traditional design and validation technologies are unable to deal with the needs for variability of context, for adaptability to changing scenarios, multiplicity of infrastructures and devices, and for addressing real-time and mobility issues. Software providers must have means to ensure and assess their confidence in the software system in advance of deployment. Consequently, techniques and tools able to predict and systematically validate the behaviour of large-scale networked software systems are necessary. Such tools, notably model checkers, have been developed within the formal methods community, and valuable lessons can also be learned from advances in theoretical computer science, and indeed in the applied mathematical analysis of complex systems in general. However, these cannot handle software adaptiveness, mobility, and system-of-systems issues. Predictable Software Systems is a paradigm which embodies the desire that pervasive complex software can be built from analysed heterogeneous components, can evolve and adapt over time, and yet where the resultant system would have predictable behaviour. The Predictable Software Systems (PSS) project is part of the Large-Scale Complex IT Systems research programme (LSCITS, pronounced else-its), a collaboration involving five institutions (www.lscits.org). The main focus of the LSCITS programme is on novel approaches and techniques for managing change. Department of Computer Science, University of Oxford Projects All oucl-All-predictablesoftware Fri, 10 Feb 2012 02:23:47 GMT