An objective comparison of the cost effectiveness of three testing methods

Branch testing is a well established method for exercising software. JJ-path testing, whilst employed by some practitioners, is less popular, and the testing of JJ-pairs finds few adherents. In this paper an objective, practical study of the cost-effectiveness of these three testing methods is reported. The effectiveness of each method is assessed, in the presence of infeasible paths, not only on its ability to cover the specific structural element of code that it targets, but also on its ability to cover the structural elements targeted by the other two methods – the collateral coverage it achieves. The assessment is based on the results derived from experiments in which each of the three methods is applied to 35 units of program code.     

Analysing the effectiveness of rule-coverage as a reduction criterion for test suites of grammar-based software

The term grammar-based software describes software whose input can be specified by a context-free grammar. This grammar may occur explicitly in the software, in the form of an input specification to a parser generator, or implicitly, in the form of a hand-written parser. Grammar-based software includes not only programming language compilers, but also tools for program analysis, reverse engineering, software metrics and documentation generation. Hence, ensuring their completeness and correctness is a vital prerequisite for their use. In this paper we propose a strategy for the construction of test suites for grammar based software, and illustrate this strategy using the ISO C^+ + grammar. We use the concept of grammar-rule coverage as a pivot for the reduction of an implementation-based test suite, and demonstrate a significant decrease in the size of this suite. The effectiveness of this reduced test suite is compared to the original test suite with respect to code coverage and more importantly, fault detection. This work greatly expands upon previous work in this area and utilises large scale mutation testing to compare the effectiveness of grammar-rule coverage to that of statement coverage as a reduction criterion for test suites of grammar-based software. This work finds that when grammar rule coverage is used as the sole criterion for reducing test suites of grammar based software, the fault detection capability of that reduced test suite is greatly diminished when compared to other coverage criteria such as statement coverage.

A comparison of the efficiency and effectiveness of vulnerability discovery techniques

ContextSecurity vulnerabilities discovered later in the development cycle are more expensive to fix than those discovered early. Therefore, software developers should strive to discover vulnerabilities as early as possible. Unfortunately, the large size of code bases and lack of developer expertise can make discovering software vulnerabilities difficult. A number of vulnerability discovery techniques are available, each with their own strengths.ObjectiveThe objective of this research is to aid in the selection of vulnerability discovery techniques by comparing the vulnerabilities detected by each and comparing their efficiencies.MethodWe conducted three case studies using three electronic health record systems to compare four vulnerability discovery techniques: exploratory manual penetration testing, systematic manual penetration testing, automated penetration testing, and automated static analysis.ResultsIn our case study, we found empirical evidence that no single technique discovered every type of vulnerability. We discovered that the specific set of vulnerabilities identified by one tool was largely orthogonal to that of other tools. Systematic manual penetration testing found the most design flaws, while automated static analysis found the most implementation bugs. The most efficient discovery technique in terms of vulnerabilities discovered per hour was automated penetration testing.ConclusionThe results show that employing a single technique for vulnerability discovery is insufficient for finding all types of vulnerabilities. Each technique identified only a subset of the vulnerabilities, which, for the most part were independent of each other. Our results suggest that in order to discover the greatest variety of vulnerability types, at least systematic manual penetration testing and automated static analysis should be performed.     

柔性板的模态价值降阶及其主动控制研究

对柔性板的模型降阶和主动控制进行研究,并且进行实验验证.首先采用假设模态方法给出系统的动力学方程,然后采用价值模态分析方法进行降阶研究.考虑到弱阻尼系统,文中给出了一种价值模态分析方法的近似公式.控制律采用最优控制方法进行设计.仿真和实验结果显示,价值模态分析方法能够有效地显示出系统各阶模态的重要程度,因此能够有效地对系统模型进行降阶.     

Improving the effectiveness of RBF classifier based on a hybrid cost function

This paper presents a new minimum classification error (MCE)–mean square error (MSE) hybrid cost function to enhance the classification ability and speed up the learning process of radial basis function (RBF)-based classifier. Contributed by the MCE function, the proposed cost function enables the RBF-based classifier to achieve an excellent classification performance compared with the conventional MSE function. In addition, certain learning difficulties experienced by the MCE algorithm can be solved in an efficient and simple way. The presented results show that the proposed method exhibits a substantially higher convergence rate compared with the MCE function.     

Mapping of improvement models as a risk reduction strategy: a theoretical comparison for the aerospace industry

Organizations involved on process improvement programs need to deal with different process improvement and assessment models. As not all the process improvement and assessment models have an equivalent scope, the selection of a particular model to guide the improvement strategy may result in a partial, constrained view of the areas where the organization may obtain competitive advantages. As a mitigation strategy, organizations should have a detailed understanding of the differences in the scope of the available models. Whatever the model they adopt, companies should be aware of relevant areas that may be missed or treated with more or less detail in the models under consideration. In addition, the need of dealing with different assessment models is usually found in second- and third-party assessments, when prospects or potential contractors decide to conduct an assessment of the subcontractor’s capabilities using a model that may not be the same as the reference model selected by the target subcontractor. In these situations, companies are at risks of overlooking relevant processes and practices. This paper describes a case study developed for the aerospace industry, based on the mapping of two assessment models widely deployed in this activity sector: CMMI-DEV and SPICE for Space, a variant of ISO/IEC 15504. A detailed gap analysis is provided identifying those aspects that should be considered both as potential improvement areas and as sources of risks. An extended assessment activity methodology is proposed that considers the results of model traceability analysis as a key factor for conducting the assessments.     

A comparison of the computatlonal complexities of the stride reduction methods

In this paper the 'Stride of 3' reduction method is compared with the wtfell known cyclic reduction method for solving tridiagonal systems derived from the discretiped steady state convection diffusion equation. The Stride of 3 algorithm is shown to be superior for moderate to large linear systems (e.g., of order > 20).     

A comparison of the balanced matrix method and the aggregation method of model reduction

The balanced matrix method and the aggregation method for model reduction are compared. It is shown that there is a "natural" choice for the aggregated reduced model output matrix that makes the aggregated model comparable to the balanced matrix reduced-order model. This assumes that the eigenvalues retained in the aggregated model are truly dominant and that the orders of the two models are equal. However, there are situations in which the choice of the eigenvalues to be retained in an aggregated model is not obvious. In these cases the balanced matrix method may be superior. The models are compared in two numerical examples.     

Investigating the defect detection effectiveness and cost benefit of nominal inspection teams

Inspection is an effective but also expensive quality assurance activity to find defects early during software development. The defect detection process, team size, and staff hours invested can have a considerable impact on the defect detection effectiveness and cost-benefit of an inspection. In this paper, we use empirical data and a probabilistic model to estimate this impact for nominal (noncommunicating) inspection teams in an experiment context. Further, the analysis investigates how cutting off the inspection after a certain time frame would influence inspection performance. Main findings of the investigation are: 1) Using combinations of different reading techniques in a team is considerably more effective than using the best single technique only (regardless of the observed level of effort). 2) For optimizing the inspection performance, determining the optimal process mix in a team is more important than adding an inspector (above a certain team size) in our model. 3) A high level of defect detection effectiveness is much more costly to achieve than a moderate level since the average cost for the defects found by the inspector last added to a team increases more than linearly with growing effort investment. The work provides an initial baseline of inspection performance with regard to process diversity and effort in inspection teams. We encourage further studies on the topic of time usage with defect detection techniques and its effect on inspection effectiveness in a variety of inspection contexts to support inspection planning with limited resources.     

A comparison of the multistep consecutive reduction mode with the multicomponent system reduction mode in cyclic voltammetry

The multistep consecutive ECE-ECE reduction process A(e)-->B(k(f2))-->C(e)-->D(e)-->E(k(f2))-->F(e)-->G has been compared with reduction in multicomponent system A(e)-->B, C(e)-->D, D(e)-->E, F(e)-->G. A simple method of transformation has been devised to disclose the subtle structure of the complex cyclic voltammetry (CV) responses and illustrated by the ECE-ECE process modeled earlier. The method can be applied to any multi-electron CV experimental curve for which a numerical modeling has been done. Electroreduction processes similar to those considered here are often met in practice. An attempt of unification of consecutive electroreduction and electroreduction of multicomponent system has been made. Interrelation between research and analytical voltammetry aspects of the problem is also discussed.     

Playing vibrotactile music: A comparison between the Vibrochord and a piano keyboard

A novel vibrotactile musical input device called the Vibrochord, which is designed to deliver patterns of vibration to the skin, not to the ear, through the use of a vibrotactile display called the Emoti-Chair, is evaluated using proposed evaluation frameworks. Findings show that the mixture of frameworks used in this study provided valuable insight into the design of this novel musical device. Results obtained through the implementation of a mixture of these frameworks show that the Vibrochord facilitated an increased accuracy rate over the traditional piano keyboard, when inexperienced vibrotactile musicians tried to repeat vibrotactile patterns or “melodies”.     

Computerization as a means of cultural change: On the relations between information theories and the idea of an information society

Since World War II the concept of Information has received several new definitions. Information can be understood as knowledge in general, as theoretical, formalized knowledge in general or as knowledge related to specific domains or specific representational forms. Because of these mutually inconsistent concepts the common traits are to be found in a perspective transcendent to those theories. The central cultural changes, it is argued, take place on the level of the societal knowledge infrastructure, evolving from the knowledge infrastructure of the industrial societies as a long-term secularization process, resulting in new forms for representation and manipulation of knowledge. The process is seen as rooted in changes of the primary domains for knowledge extraction and in a change in the human relations to the languages in which we interpret the relations to nature.     

The Comparison between the Statistical Heuristic Search and A

In order to further unravel the principle and performance of the statistical heuristic seach algorithm S A,in this paper,in comparison with A * search,the hypothesis,performance and computational complexity of SA are discussed.     

A comparison of the effectiveness of e-mail coupons and mobile text message coupons for digital products

An increasing number of companies are focusing on e-mail and mobile marketing to promote offers. The aim of this study is to analyze a coupon campaign for a 67 % price discount on downloadable personal computer (PC) software. The campaign was carried out via e-mail and mobile text messages. Using an opt-in database, we gathered data from more than 37,000 participants and compared the response and conversion rates for both e-mail and mobile text messaging. The results indicated that the response rate for e-mail coupons is higher than the response rate for mobile text message coupons, but text messages yield a better conversion rate and a higher number of total purchases. After calculating the price elasticities for both communication channels, we found that the promotional price elasticity is higher for mobile text message coupons than for e-mail coupons.     

逻辑程序设计语言G(o)del与Prolog的比较

在多态多类的一阶逻辑基础之上,围绕类型系统、模块系统、控制机制、元程序设计和输入／输出部分对Gǒdel语言功能进行分析。重点比较了逻辑程序设计语言Gǒdel与Prolog的联系与区别,通过比较分析,表明由于摒弃了Prolog语言中的非逻辑成分,引入了多种新的语言成分,Gǒdel语言具有更好的说明性语义和执行效率。     

A detailed description of a computer system for the routing and scheduling of street sweepers

In [3], the basic street sweeper routing and scheduling problem was described. In this paper, a detailed examination of the first nine steps in the computerized street sweeper routing system (disregarding the final output step) is given. To further illustrate these ideas, an example is worked out in detail.     

邓小平与毛泽东西部开发思想的比较

毛泽东和邓小平,作为我党第一代和第二代领导集体的核心,他们都曾提出关于中国西部经济发展的思想和理论。认真学习这些思想,研究比较它们之间的异同,对于今天我们深入理解邓小平理论与毛泽东思想之间继承和发展的关系;对于推动西部改革开放的进程,加快西部大开发都有着十分重要的现实指导意义。     

A DEA‐based method of allocating the fixed cost as a complement to the original input

This paper focuses on the problem of how to divide a fixed cost as a complement to an original input among decision‐making units (DMUs) equitably. Using the data envelopment analysis (DEA) technique, this paper concerns the problem from the perspective of efficiency analysis. It is found that not all DMUs can become efficient under common weights if a low enough fixed cost is assigned. Therefore, the global modified additive DEA (MAD) model is introduced. By optimizing the global MAD‐efficiency, a new allocation method and the corresponding algorithm to ensure the uniqueness of the allocation result is designed. The proposed method can be used under both constant returns to scale and variable returns to scale for nonnegative data; it is suitable for the situation where the costs play a great role in the production of DMUs. Numerical results show the validity and advantages of our method.