974 resultados para test case generation


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Wolfram von Eschenbach’s novel Parzival is a courtly romance composed in German language shortly after 1200. In a project, based at the University of Bern, a new critical edition of the poem is prepared in electronic and printed form. It visualizes parallel textual versions, which, depending on particular circumstances of oral performance, have developed in the early stage of the poem’s transmission. Philological research as well as phylogenetic techniques common in the natural sciences, e.g. in molecular biology, have been used to demonstrate the existence of these early textual versions. The article shows how both methods work and how they are applied to the ongoing edition. Exemplary passages to be presented include the text of some rare fragments written in the first decades of the 13th century, which might even go back to the author’s lifetime and which allow to date the existence of the versions they belong to.

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This paper presents a gravimetric study (based on 382 gravimetric stations in an area about 32 km2) of a nearly flat basin: the Low Andarax valley. This alluvial basin, close to its river mouth, is located in the extreme south of the province of Almería and coincides with one of the existing depressions in the Betic Cordillera. The paper presents new methodological work to adapt a published inversion approach (GROWTH method) to the case of an alluvial valley (sedimentary stratification, with density increase downward). The adjusted 3D density model reveals several features in the topography of the discontinuity layers between the calcareous basement (2,700 kg/m3) and two sedimentary layers (2,400 and 2,250 kg/m3). We interpret several low density alignments as corresponding to SE faults striking about N140?145°E. Some detected basement elevations (such as the one, previously known by boreholes, in Viator village) are apparently connected with the fault pattern. The outcomes of this work are: (1) new gravimetric data, (2) new methodological options, and (3) the resulting structural conclusions.

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Many small bacterial, archaebacterial, and eukaryotic genomes have been sequenced, and the larger eukaryotic genomes are predicted to be completely sequenced within the next decade. In all genomes sequenced to date, a large portion of these organisms’ predicted protein coding regions encode polypeptides of unknown biochemical, biophysical, and/or cellular functions. Three-dimensional structures of these proteins may suggest biochemical or biophysical functions. Here we report the crystal structure of one such protein, MJ0577, from a hyperthermophile, Methanococcus jannaschii, at 1.7-Å resolution. The structure contains a bound ATP, suggesting MJ0577 is an ATPase or an ATP-mediated molecular switch, which we confirm by biochemical experiments. Furthermore, the structure reveals different ATP binding motifs that are shared among many homologous hypothetical proteins in this family. This result indicates that structure-based assignment of molecular function is a viable approach for the large-scale biochemical assignment of proteins and for discovering new motifs, a basic premise of structural genomics.

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In this CEPS Commentary, the former Irish Prime Minister calls the precedents being set in the Cypriot banking case “troubling” and reflective of a lack of clarity and consistency of thought by both the eurozone Finance Ministers and the European Commission. He welcomes the rejection of the deal by the Cypriot Parliament as it now gives eurozone policy-makers a chance to think again about the underlying philosophy of their approach to the financial crisis.

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The eruption of Tambora (Indonesia) in April 1815 had substantial effects on global climate and led to the ‘Year Without a Summer’ of 1816 in Europe and North America. Although a tragic event — tens of thousands of people lost their lives — the eruption also was an ‘experiment of nature’ from which science has learned until today. The aim of this study is to summarize our current understanding of the Tambora eruption and its effects on climate as expressed in early instrumental observations, climate proxies and geological evidence, climate reconstructions, and model simulations. Progress has been made with respect to our understanding of the eruption process and estimated amount of SO2 injected into the atmosphere, although large uncertainties still exist with respect to altitude and hemispheric distribution of Tambora aerosols. With respect to climate effects, the global and Northern Hemispheric cooling are well constrained by proxies whereas there is no strong signal in Southern Hemisphere proxies. Newly recovered early instrumental information for Western Europe and parts of North America, regions with particularly strong climate effects, allow Tambora’s effect on the weather systems to be addressed. Climate models respond to prescribed Tambora-like forcing with a strengthening of the wintertime stratospheric polar vortex, global cooling and a slowdown of the water cycle, weakening of the summer monsoon circulations, a strengthening of the Atlantic Meridional Overturning Circulation, and a decrease of atmospheric CO₂. Combining observations, climate proxies, and model simulations for the case of Tambora, a better understanding of climate processes has emerged.

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Many models have been advanced to suggest how different expressions of sociality have evolved and are maintained. However these models ignore the function of groups for the particular species in question. Here we present a new perspective on sociality where the function of the group takes a central role. We argue that sociality may have primarily a reproductive, protective, or foraging function, depending on whether it enhances the reproductive, protective or foraging aspect of the animal's life (sociality may serve a mixture of these functions). Different functions can potentially cause the development of the same social behaviour. By identifying which function influences a particular social behaviour we can determine how that social behaviour will change with changing conditions, and which models are most pertinent. To test our approach we examined spider sociality, which has often been seen as the poor cousin to insect sociality. By using our approach we found that the group characteristics of eusocial insects is largely governed by the reproductive function of their groups, while the group characteristics of social spiders is largely governed by the foraging function of the group. This means that models relevant to insects may not be relevant to spiders. It also explains why eusocial insects have developed a strict caste system while spider societies are more egalitarian. We also used our approach to explain the differences between different types of spider groups. For example, differences in the characteristics of colonial and kleptoparasitic groups can be explained by differences in foraging methods, while differences between colonial and cooperative spiders can be explained by the role of the reproductive function in the formation of cooperative spider groups. Although the interactions within cooperative spider colonies are largely those of a foraging society, demographic traits and colony dynamics are strongly influenced by the reproductive function. We argue that functional explanations help to understand the social structure of spider groups and therefore the evolutionary potential for speciation in social spiders.

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Modern software application testing, such as the testing of software driven by graphical user interfaces (GUIs) or leveraging event-driven architectures in general, requires paying careful attention to context. Model-based testing (MBT) approaches first acquire a model of an application, then use the model to construct test cases covering relevant contexts. A major shortcoming of state-of-the-art automated model-based testing is that many test cases proposed by the model are not actually executable. These \textit{infeasible} test cases threaten the integrity of the entire model-based suite, and any coverage of contexts the suite aims to provide. In this research, I develop and evaluate a novel approach for classifying the feasibility of test cases. I identify a set of pertinent features for the classifier, and develop novel methods for extracting these features from the outputs of MBT tools. I use a supervised logistic regression approach to obtain a model of test case feasibility from a randomly selected training suite of test cases. I evaluate this approach with a set of experiments. The outcomes of this investigation are as follows: I confirm that infeasibility is prevalent in MBT, even for test suites designed to cover a relatively small number of unique contexts. I confirm that the frequency of infeasibility varies widely across applications. I develop and train a binary classifier for feasibility with average overall error, false positive, and false negative rates under 5\%. I find that unique event IDs are key features of the feasibility classifier, while model-specific event types are not. I construct three types of features from the event IDs associated with test cases, and evaluate the relative effectiveness of each within the classifier. To support this study, I also develop a number of tools and infrastructure components for scalable execution of automated jobs, which use state-of-the-art container and continuous integration technologies to enable parallel test execution and the persistence of all experimental artifacts.

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提出了带约束事件的时序逻辑TLCE,用于描述系统运行中输入/输出事件之间的时序关系以及对事件参数的数据相关性约束.阐述了一种基于模型的并发系统测试框架,采用TLCE描述测试目的以引导测试用例生成.缓存一致性协议和会议协议的实例研究中所生成的测试用例集显著优于随机测试用例集.这说明了TLCE作为测试目的描述的有效性.

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编译优化是现代编译器的重要功能,编译优化测试对保障现代编译器质量有着重要作用。编译优化测试需要编写大量的测试用例程序作为输入,手工完成十分费时费力,因此,有必要研究编译优化测试用例的自动生成方法。 针对编译优化测试,有研究者提出并实现了一种基于分支时序逻辑的测试用例自动生成方法COT。该方法可以有效地生成标量优化测试用例程序,但该方法没有考虑程序中的数组和指针,对优化特征的描述也不能区分循环迭代中的语句实例,更不能刻画语句实例间的数据依赖关系,然而这些是刻画循环优化所必需的,因此,COT不适用于循环优化测试用例的自动生成。 本文针对COT方法的缺陷,首先提出了基于参数化分支时序逻辑pCTL (parameterized computation temporal logic)的循环优化描述方法,通过参数化COT的优化描述体系中的语句谓词、变量引用谓词和变量定义谓词实现了对循环迭代中的语句实例及语句实例间的数据依赖关系的描述。在此基础上,本文提出了基于pCTL 描述的循环优化测试用例自动生成方法COT2。该方法根据pCTL公式构造初始的关键节点控制图,再按照公式语义执行公式处理和虚边替换,得到完整的控制流图,最后计算数组引用下标,生成循环优化测试用例程序。 本文实现了COT2的系统原型,并用循环优化模块的覆盖率指标评价生成的测试用例的质量,实验结果表明该方法对循环优化具有针对性,是一种行之有效的方法。本文还用生成的测试用例程序对GCC各版本的循环优化模块进行了测试,并分析了错误发现数与各版本稳定性之间的关系,进一步验证了本文方法的有效性。

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近年来,以数据依赖分析为基础的高级编译优化成为现代编译器的重要研发内容.针对这类编译优化的测试问题提出了一种测试程序自动生成方法,能够根据指定的数据依赖特征生成测试程序.首先设计了LoSpec语言用以描述测试程序,然后采用一种便于表示数据依赖关系的模型——过程图作为中间表示模型实现了测试程序的自动生成,并开发了自动测试工具LoTester.与已有方法相比,该方法对高级优化更具针对性,自动化程度较高.LoTester目前在一款面向多媒体应用的优化编译器EECC的开发中得到应用并获得了良好效果.

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编译器的质量保证对提高软件产品的质量有着重要作用,对编译优化的测试是其中的核心部分.对编译优化的测试需要大量的测试用例程序.要构造这些测试用例,使用传统手工构造方法面临着效率低的问题,而基于文法的构造方法则针对性不足.从对优化的形式化描述出发来自动构造测试用例能克服这些缺点.本文设计并实现了一种基于形式化描述的编译优化测试用例程序生成方法.该方法基于编译优化的时序逻辑描述构造关键顶点控制流图,逐步转换为控制流图并得到用例程序.针对GCC(版本4.1.1)进行的覆盖率测试实验表明,该方法可以生成具有较高针对性的测试用例,并达到相当的覆盖程度.