28 research outputs found

    Verification of floating point programs

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    In this thesis we present an approach to automated verification of floating point programs. Existing techniques for automated generation of correctness theorems are extended to produce proof obligations for accuracy guarantees and absence of floating point exceptions. A prototype automated real number theorem prover is presented, demonstrating a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The prototype is tested on correctness theorems for two simple yet nontrivial programs, proving exception freedom and tight accuracy guarantees automatically. The prover demonstrates a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The experiments show how function intervals can be used to combat the information loss problems that limit the applicability of traditional interval arithmetic in the context of hard real number theorem proving

    Towards flexible goal-oriented logic programming

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    Verification of floating point programs

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    In this thesis we present an approach to automated verification of floating point programs. Existing techniques for automated generation of correctness theorems are extended to produce proof obligations for accuracy guarantees and absence of floating point exceptions. A prototype automated real number theorem prover is presented, demonstrating a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The prototype is tested on correctness theorems for two simple yet nontrivial programs, proving exception freedom and tight accuracy guarantees automatically. The prover demonstrates a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The experiments show how function intervals can be used to combat the information loss problems that limit the applicability of traditional interval arithmetic in the context of hard real number theorem proving.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Workshop on Database Programming Languages

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    These are the revised proceedings of the Workshop on Database Programming Languages held at Roscoff, Finistère, France in September of 1987. The last few years have seen an enormous activity in the development of new programming languages and new programming environments for databases. The purpose of the workshop was to bring together researchers from both databases and programming languages to discuss recent developments in the two areas in the hope of overcoming some of the obstacles that appear to prevent the construction of a uniform database programming environment. The workshop, which follows a previous workshop held in Appin, Scotland in 1985, was extremely successful. The organizers were delighted with both the quality and volume of the submissions for this meeting, and it was regrettable that more papers could not be accepted. Both the stimulating discussions and the excellent food and scenery of the Brittany coast made the meeting thoroughly enjoyable. There were three main foci for this workshop: the type systems suitable for databases (especially object-oriented and complex-object databases,) the representation and manipulation of persistent structures, and extensions to deductive databases that allow for more general and flexible programming. Many of the papers describe recent results, or work in progress, and are indicative of the latest research trends in database programming languages. The organizers are extremely grateful for the financial support given by CRAI (Italy), Altaïr (France) and AT&T (USA). We would also like to acknowledge the organizational help provided by Florence Deshors, Hélène Gans and Pauline Turcaud of Altaïr, and by Karen Carter of the University of Pennsylvania

    Social Net-working: Exploring the Political Economy of the Online Social Network Industry

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    This study explores the nascent political economy of the online social network industry. Exemplars of online social networking, Facebook and Twitter have often been understood as revolutionary New Media tools. My findings show that these social networks are taking on a logic of capitalist production and accumulation, calling into question their revolutionary character. Evidence suggests that user-generated content are now being commodified and exchanged for profit. A critical discourse analysis of Facebook and Twitter’s privacy policy and terms-of-use reveals that these texts primarily function as work contracts rather than treatises on privacy protection. Drawing on the work of Karl Marx, this study revisits his theory of value and develops an expanded form of variable capital model to demonstrate how social networkers fit into this new capitalist circuit of accumulation. This extension of the working day is problematic. Policy recommendations are offered in order to negate the commodification of user data

    The Meaning of UML Models

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    The Unified Modelling Language (UML) is intended to express complex ideas in an intuitive and easily understood way. It is important because it is widely used in software engineering and other disciplines. Although an official definition document exists, there is much debate over the precise meaning of UML models. ¶ In response, the academic community have put forward many different proposals for formalising UML, but it is not at all obvious how to decide between them. Indeed, given that UML practitioners are inclined to reject formalisms as non-intuitive, it is not even obvious that the definition should be “formal” at all. Rather than searching for yet another formalisation of UML, our main aim is to determine what would constitute a good definition of UML. ¶ The first chapter sets the UML definition problem in a broad context, relating it to work in logic and the philosophy of science. ..

    Computer Aided Verification

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    This open access two-volume set LNCS 11561 and 11562 constitutes the refereed proceedings of the 31st International Conference on Computer Aided Verification, CAV 2019, held in New York City, USA, in July 2019. The 52 full papers presented together with 13 tool papers and 2 case studies, were carefully reviewed and selected from 258 submissions. The papers were organized in the following topical sections: Part I: automata and timed systems; security and hyperproperties; synthesis; model checking; cyber-physical systems and machine learning; probabilistic systems, runtime techniques; dynamical, hybrid, and reactive systems; Part II: logics, decision procedures; and solvers; numerical programs; verification; distributed systems and networks; verification and invariants; and concurrency

    Computer Aided Verification

    Get PDF
    This open access two-volume set LNCS 11561 and 11562 constitutes the refereed proceedings of the 31st International Conference on Computer Aided Verification, CAV 2019, held in New York City, USA, in July 2019. The 52 full papers presented together with 13 tool papers and 2 case studies, were carefully reviewed and selected from 258 submissions. The papers were organized in the following topical sections: Part I: automata and timed systems; security and hyperproperties; synthesis; model checking; cyber-physical systems and machine learning; probabilistic systems, runtime techniques; dynamical, hybrid, and reactive systems; Part II: logics, decision procedures; and solvers; numerical programs; verification; distributed systems and networks; verification and invariants; and concurrency

    Temporal meta-model framework for Enterprise Information Systems (EIS) development

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    This thesis has developed a Temporal Meta-Model Framework for semi-automated Enterprise System Development, which can help drastically reduce the time and cost to develop, deploy and maintain Enterprise Information Systems throughout their lifecycle. It proposes that the analysis and requirements gathering can also perform the bulk of the design phase, stored and available in a suitable model which would then be capable of automated execution with the availability of a set of specific runtime components

    Origins and development of representational systems in early childhood

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    It is argued in Chapters 1 to 4 that in cognitive psychology in general, and in the disciplines of language acquisition and cognitive development in particular, there is substantial benefit to be derived from distinguishing between two representational systems, one system being deployed in long-established or highly-practiced functions, and the second deployed in novel tasks, or where difficulties interrupt the first system. It is also argued that the proper subject of cognitive development is the second of these systems. Chapters 5 and 6 are concerned in different ways with the origins of language in the individual, in particular with the question of what innate knowledge of language might be justified. It is concluded that many questions regarding innate knowledge remain open, and that a source in human evolution for knowledge of language is no more likely than sources in individual or social development. In Chapter 7 it is argued that representational drawing emerges late in the 4th year of life, and some new techniques are described for studying early representational drawing. Following these treatments of external systems of representation, Chapter 8 offers a general developmental theory of forms of representation, extending Piaget's insight that mental representation is co-extensive with thought, and that the main axis of cognitive development is the content of thought and representation. Chapters 9 to 12 apply this theory to the representation of belief and desire, and of extrinsic and intrinsic qualities of objects, by 11/2 to 4 year-old children. Chapter 13 introduces a new method for analyzing the free classification task, a task sometimes used to assess children's ability to think about intrinsic qualities, and applies this method to various data sets. Chapter 14 applies these insights and results to the problem of characterizing concepts and concept development and favourably discusses the idea that more precise knowledge of this aspect of development may help to explain certain features of early language acquisition
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