65,566 research outputs found

    Differentially Testing Soundness and Precision of Program Analyzers

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    In the last decades, numerous program analyzers have been developed both by academia and industry. Despite their abundance however, there is currently no systematic way of comparing the effectiveness of different analyzers on arbitrary code. In this paper, we present the first automated technique for differentially testing soundness and precision of program analyzers. We used our technique to compare six mature, state-of-the art analyzers on tens of thousands of automatically generated benchmarks. Our technique detected soundness and precision issues in most analyzers, and we evaluated the implications of these issues to both designers and users of program analyzers

    Towards a method for rigorous development of generic requirements patterns

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    We present work in progress on a method for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. Our chosen application domain is the failure detection and management function for engine control systems: here generic requirements drive a software product line of target systems. A pilot formal specification and design exercise is undertaken on a small (twosensor) system element. This exercise has a number of aims: to support the domain analysis, to gain a view of appropriate design abstractions, for a B novice to gain experience in the B method and tools, and to evaluate the usability and utility of that method.We also present a prototype method for the production and verification of a generic requirement set in our UML-based formal notation, UML-B, and tooling developed in support. The formal verification both of the structural generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

    A literature-based comparison of nutrient and contaminant contents between organic and conventional vegetables and potatoes

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    Purpose - The increasing demand for organic foods is explained mainly by consumers' concerns about the quality and safety of foods and their perception that organically produced foods are healthier and safer than conventional foods. Based on internationally available concentration data of organic and conventional vegetables (carrots, tomatoes, lettuce and spinach) and potatoes, the paper aims to investigate the scientific validity of nutrition claims as "no vegetable/potato has higher amounts of nutrient X than organic vegetables/potatoes" and "no vegetable/potato has lower amounts of contaminant Y than organic vegetables/potatoes". Design/methodology/approach - Detailed nutrient and contaminant databases were developed for organic and conventional vegetables separately. Non-parametric (Mann-Whitney test) methods were used to detect significant differences between both types of vegetables. A chi-square test was used to compare the incidence of pesticide residues in organic and conventional vegetables. Findings - From a nutritional and toxicological point of view, organic vegetables and potato in general are not significantly better than conventional vegetables and potatoes. For some nutrients and contaminants organic vegetables and potatoes score significantly better but for others they score significantly worse. Therefore, it becomes difficult to justify general claims indicating a surplus value of organic over conventional vegetables and potatoes. More data from controlled paired studies are needed to reconsider the use of claims for these organic plant foods in the future. Research limitations/implications - Only a limited number of studies comparing the nutrient and/or contaminant concentration of organic and conventional vegetables are available ("paired studies"). Additionally, the majority of the studies are of moderate or poor quality. The implication is that more of those paired studies are heavily needed. Another limitation of the study is the fact that most pesticide residue data originated from the USA, the EU and Australia. Originality/value - So far only few studies compared both nutrient and contaminant contents between organic and conventional plant foods. This paper covers therefore an important, not well-explored research sub area

    Quality analysis of critical control points within the whole food chain and their impact on food quality, safety and health (QACCP)

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    The overall objective of the project was to optimise organic production and processing in order to improve food quality and increase health promoting aspects in consumer products. The approach was a chain analysis approach which addressed the link between farm and fork and backwards from fork to farm. The objectives were to test food authenticity on farm level and food quality and health in processing. The carrot was chosen as the model vegetable since it is common for the involved partners from industry and is processed for baby food; hence the results are relevant for other vegetables and organic food in general as well. - Identify and define critical and essential product quality parameters useful to optimise organic food quality - Compare products from different farming practices (conventional and within organic) - Performance of QACCP (Quality Analysis Critical Control Point, similar to HACCP methodology) - Test the impact of the food chain (focusing on processing techniques) on the product quality and safety - Test the impact of organic food on healt

    Developing a distributed electronic health-record store for India

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    The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

    Towards Identifying and closing Gaps in Assurance of autonomous Road vehicleS - a collection of Technical Notes Part 1

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    This report provides an introduction and overview of the Technical Topic Notes (TTNs) produced in the Towards Identifying and closing Gaps in Assurance of autonomous Road vehicleS (Tigars) project. These notes aim to support the development and evaluation of autonomous vehicles. Part 1 addresses: Assurance-overview and issues, Resilience and Safety Requirements, Open Systems Perspective and Formal Verification and Static Analysis of ML Systems. Part 2: Simulation and Dynamic Testing, Defence in Depth and Diversity, Security-Informed Safety Analysis, Standards and Guidelines
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