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951.
Claudia AyalaAuthor Vitae Øyvind HaugeAuthor Vitae 《Journal of Systems and Software》2011,84(4):620-637
The success of software development using third party components highly depends on the ability to select a suitable component for the intended application. The evidence shows that there is limited knowledge about current industrial OTS selection practices. As a result, there is often a gap between theory and practice, and the proposed methods for supporting selection are rarely adopted in the industrial practice. This paper's goal is to investigate the actual industrial practice of component selection in order to provide an initial empirical basis that allows the reconciliation of research and industrial endeavors. The study consisted of semi-structured interviews with 23 employees from 20 different software-intensive companies that mostly develop web information system applications. It provides qualitative information that help to further understand these practices, and emphasize some aspects that have been overlooked by researchers. For instance, although the literature claims that component repositories are important for locating reusable components; these are hardly used in industrial practice. Instead, other resources that have not received considerable attention are used with this aim. Practices and potential market niches for software-intensive companies have been also identified. The results are valuable from both the research and the industrial perspectives as they provide a basis for formulating well-substantiated hypotheses and more effective improvement strategies. 相似文献
952.
Flash memory efficient LTL model checking 总被引:1,自引:0,他引:1
S. EdelkampD. Sulewski J. BarnatL. Brim P. Šime?ek 《Science of Computer Programming》2011,76(2):136-157
As the capacity and speed of flash memories in form of solid state disks grow, they are becoming a practical alternative for standard magnetic drives. Currently, most solid-state disks are based on NAND technology and much faster than magnetic disks in random reads, while in random writes they are generally not.So far, large-scale LTL model checking algorithms have been designed to employ external memory optimized for magnetic disks. We propose algorithms optimized for flash memory access. In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection.For flash memory efficient on-the-fly LTL model checking, which aims at finding any counter-example to the specified LTL property, we study hash functions adapted to the two-level hierarchy of RAM and flash memory. For flash memory efficient off-line LTL model checking, which aims at generating a minimal counterexample and scans the entire state space at least once, we analyze the effect of outsourcing a memory-based perfect hash function from RAM to flash memory.Since the characteristics of flash memories are different to magnetic hard disks, the existing I/O complexity model is no longer sufficient. Therefore, we provide an extended model for the computation of the I/O complexity adapted to flash memories that has a better fit to the observed behavior of our algorithms. 相似文献
953.
Rita A. RibeiroAuthor Vitae Ana M. MoreiraAuthor VitaePim van den BroekAuthor Vitae Afonso PimentelAuthor Vitae 《Decision Support Systems》2011,51(1):208-219
During software development, many decisions need to be made to guarantee the satisfaction of the stakeholders' requirements and goals. The full satisfaction of all of these requirements and goals may not be possible, requiring decisions over conflicting human interests as well as technological alternatives, with an impact on the quality and cost of the final solution. This work aims at assessing the suitability of multi-criteria decision making (MCDM) methods to support software engineers' decisions. To fulfil this aim, a HAM (Hybrid Assessment Method) is proposed, which gives its user the ability to perceive the influence different decisions may have on the final result. HAM is a simple and efficient method that combines one single pairwise comparison decision matrix (to determine the weights of criteria) with one classical weighted decision matrix (to prioritize the alternatives). To avoid consistency problems regarding the scale and the prioritization method, HAM uses a geometric scale for assessing the criteria and the geometric mean for determining the alternative ratings. 相似文献
954.
Markus DurzinskyAnnegret Wagler Robert Weismantel 《Theoretical computer science》2011,412(26):2800-2815
Models of biological systems and phenomena are of high scientific interest and practical relevance, but not always easy to obtain due to their inherent complexity. To gain the required insight, experimental data are provided and need to be interpreted in terms of models that explain the observed phenomena. In systems biology the framework of Petri nets is often used to describe models for the regulatory mechanisms of biological systems. The aim of this paper is to provide, based on results in Marwan et al. (2008) [1] and Durzinsky et al. (2008) [2], an algorithmic framework for the challenging task of generating all possible Petri nets fitting the given experimental data. 相似文献
955.
对于化工过程或相关的工程实验等工程实际问题,数学上直接应用基本方程求解极为困难,有赖于实验研究来解决。因次分析方法将工程实际问题中实验条件下物理量之间的关联视为无因次量之间的关联,大大降低变量数目,成数量级地减少实验工作量,使相关物理量较多的化工过程通过实验获得物理量之间的关联成为可能。对于复杂的化工过程等实际问题,经典的因次分析方法涉及化工过程建模、若干个方程组的求解及大量重复而以烦琐的数学计算,才能找出这些无因次量之间关联。采用ActiveX技术与VBA混合编程进行因次分析,自动选择核心物理量、求出核心物理量待定幂次,自动对数群的4项核心物理量幂次与数群物理量组合表对照、确定无因次数群。利用VBA混合编程自动实现工程实验的因次分析,获得实验模型与原型结构之间的相似准则,建立并简化了实验关联公式,并通过示例,阐述了因次分析的自动化方法及其实现过程。因次分析自动化方法应用于学生毕业论文的工程实验设计中,分析化工过程的相似关系,为指导毕业论文的工程实验提供可靠依据,使用方便,收效良好。 相似文献
956.
957.
958.
基于SOFM神经网络构建的三角形网格模型可以实现测量点云压缩后的Delaunay三角逼近剖分,但该模型存在边缘误差。为减小三角形网格的边缘误差,改进了三角形网格模型的训练模式,提出了3步训练模式。第1步采用整个测量点云,对三角形网格模型中的所有神经元进行整体训练;第2步采用测量点云中的边界点集,对三角形网格模型中的网格边界神经元进行训练;第3步采用边界点集中的角点点集,对与边界角点匹配最佳的网格边界神经元进行训练。算例表明,应用该训练模式,可以有效减小三角形网格的边缘误差,三角形网格逼近散乱点云的逼近精度得到提高并覆盖散乱点云整体分布范围。 相似文献
959.
浅谈MATLAB在化工计算中的应用 总被引:42,自引:26,他引:16
MATLAB是Mathworks公司推出的适用于科学和工程计算的数学软件系统,可高效地解决数值线性代数、微分方程数值解、数值逼近、最优化、数值积分等科学和工程问题,且具有数值稳定性好,使用方便等特点本文对化工中的4个典型计算为例,讨论了MATLAB在化工计算中的应用。 相似文献
960.
紧耦合多处理机系统在工程飞行仿真中的实时应用 总被引:8,自引:0,他引:8
介绍了以 Windows NT为操作系统的紧耦合多处理机系统,研究了在此平台上开发实时应用系统的方法,并将其应用到工程飞行仿真中。介绍了工程飞行仿真的概念以及工程飞行仿真中实时管理系统的分析与设计。 相似文献