基于层次和数据流驱动的软件可靠性分配方法

为了提高软件可靠性分配的有效性, 提出了一种基于层次和数据流驱动的软件可靠性分配方法。该方法对传统的重要度、复杂度度量方法进行改进; 针对软件系统开发初期体系结构中系统模块层次关系及模块间数据流关系进行抽象, 形成体系结构形式化定义, 建立可靠性因子的度量准则及度量模型, 依据度量模型对可靠性进行分配。最后结合实例进行了分析和验证, 结果表明了该分配模型的有效性和可行性。     

基于UML的复杂装备测试性需求建模

提出了一种基于UML的复杂装备测试性需求分析模型。首先分析了测试性需求分析过程;然后描述了统一建模语言（UML）测试性需求建模思想;最后构建了以用例模型、静态模型和动态模型为主的测试性需求分析模型,该模型详细描述了测试性需求分析过程中的系统信息管理和确定测试性指标要求的用例、对象信息以及交互行为,保证了信息的完备性和模型的有效性。通过开发测试性需求分析软件系统,并对某导弹进行测试性需求分析和指标确定,验证了结果的可信性和方法的有效性,为开展装备测试性需求分析和指标确定奠定了基础。     

基于人类视觉系统的视频编码方法

提出一种基于视觉特点的视频编码方法,通过利用人眼的视觉特征,找出其中的聚焦点和聚焦区域,并计算各个区域的权值,然后根据权值来确定各个运动补偿块以及码率分配。在码率分配部分,该方法通过计算不同区域的图像复杂性和能量,依据聚焦区权重因子不等重地分配可用码率资源。实验证明,该方法较大程度改善了视频编码的压缩效率,提高了码率分配的灵活性和有效性。     

提高案例推理分类器的可靠性研究

针对案例推理（Case-based reasoning,CBR）分类器的可靠性问题,本文提出一种改进的案例检索和案例重用方法. 首先在案例检索环节应用注水原理对属性权重进行优化分配,利用每个属性数据的标准差和均值构造拉格朗日函数求得属性权重,并设定重要度阈值指导属性约简;其次在案例重用环节引入基于可信度的重用策略,通过计算目标案例分属于各个类别的可信度大小来确定当前案例的分类结果. 最后通过实验对比,表明本文方法能有效提高分类精度和效率,分类器的可靠性得以保障.     

熵加权多视角核K-means算法

在基于视角加权的多视角聚类中,每个视角的权重取值对聚类结果的精度都有着重要的影响。针对此问题,提出熵加权多视角核K-means(EWKKM) 算法,通过给每个视角分配一个合理的权值来降低噪声视角或无关视角对多视角聚类的影响,进而提高聚类的精度。EWKKM算法中,首先用核矩阵表示不同的视角,给每个视角分配一个权重;然后,利用信息熵计算出各个视角的熵权重;最后,按照定义的目标函数对各个视角的权重进行优化,使用核K-means进行多视角聚类。在UCI数据集及人工数据集进行实验,实验结果表明熵加权多视角核K-means算法能够为每个视角分配一个最优的权重值,聚类的精确度优于已有的聚类算法,具有更稳定的聚类结果。     

基于差分进化的复杂软件系统动态可靠性分配

现有关于复杂软件系统可靠性分配的研究均基于结构固定的软件系统,而实际情况中软件系统结构往往不固定。针对这一矛盾,构建复杂软件系统动态可靠性分配优化模型,并基于差分进化设计复杂软件系统动态可靠性分配算法。在系统结构发生变化时,首先基于D-S证据理论对系统中各模块的全局权重重新进行评估,并考虑变化前后系统的关联性,在差分进化生成初始种群时保留了部分历史解。最后,通过仿真实验分析验证了所提方法的有效性。     

基于CRITIC权与灰色关联的隐写分析算法综合评估

在基于灰色关联分析的隐写分析算法评估过程中,针对权值分配不合理的问题,采用标准间重要性相关性方法确定各指标的初始权重,结合决策情况对待主动修改的指标权重进行增减,并将这些增减的权重平均分配给被动变化的指标,从而实现对权重的调整,得到各指标的最终权值。运用灰色关联分析法计算各个待评价对象与最优序列之间的加权灰色关联度,并依据加权关联度的大小完成对隐写分析算法的评估。仿真结果表明,与其他隐写分析算法相比,该方法能更加有效地评估各类隐写分析算法的优劣。     

基于UML的仓储管理系统的分析设计

统一建模语言(UML)是面向对象分析和设计过程中重要的建模工具,适用于软件生命周期的各个阶段.以仓储管理系统为例,采用面向对象的方法,介绍UML的建模机制;叙述了仓储管理系统的用例建模、动态建模的过程,详细描述了基于UML该系统的用例图、活动图、顺序图、协作图.     

以UML用例图为基础的系统需求分析

UML是目前面向对象程序设计中的一种标准建模技术，它被用作确定、可视化、构建和文档化一个软件系统的结构。本文主要探讨以UML用例图为中心及出发点，类图、交互图为实现手段，捕获高层次的系统功能需求的策略。     

故障样本的多指标集成加权分配方法

针对测试性验证实验中故障样本分配结果置信度比较低的问题,提出了一种多指标集成加权的分配方法。首先,综合分析故障属性与环境因子对故障样本分配结果置信度的影响,在此基础上,定量计算影响指标的值;其次,采用集成加权法确定各个指标的权重;最后,利用归一化后的指标比值进行故障样本分配。该方法改进了故障率、严酷度、危害度及指标权重的计算方法,并提出了故障样本分配中故障-环境关联度的计算方法。在某型装备故障样本分配中的应用结果表明,该方法的分配结果更合理,置信度更高,更具有实际应用价值。     

On the reliability of AI planning software in real-timeapplications

We define the reliability of a real-time system incorporating AI planning programs as the probability that, for each problem-solving request issued from the environment, the embedded system can successfully plan and execute a response within a specified real-time deadline. A methodology is developed for evaluating the reliability of such systems taking into consideration the fact that, other than program bugs, the intrinsic characteristics of AI planning programs may also cause the embedded system to fail even after all software bugs are removed from the program. The utility of the methodology is demonstrated by applying it to the reliability evaluation of two AI planning algorithms embedded in a real-time multicriteria route finding system     

基于BSC-AHP的绩效评估模型研究与实现

为了解决企业战略目标执行难的问题,提升绩效评估合理性。笔者在深入研究现存理论和方法的基础上,采用平衡记分卡理论从企业战略目标中提取关键评估指标,并提出了用分解矩阵的方法将评估指标分解到各评估对象。最后引用层次分析法确定各指标权重。建立了引导、鼓励员工工作向有利于企业战略的执行与控制的绩效评估指标体系和评价模型。开发的系统在某印刷企业得到应用并取得良好效果,有效证明了模型的可行性和科学性。     

Architectural-level risk analysis using UML

Risk assessment is an essential part in managing software development. Performing risk assessment during the early development phases enhances resource allocation decisions. In order to improve the software development process and the quality of software products, we need to be able to build risk analysis models based on data that can be collected early in the development process. These models will help identify the high-risk components and connectors of the product architecture, so that remedial actions may be taken in order to control and optimize the development process and improve the quality of the product. In this paper, we present a risk assessment methodology which can be used in the early phases of the software life cycle. We use the Unified Modeling Language (UML) and commercial modeling environment Rational Rose Real Time (RoseRT) to obtain UML model statistics. First, for each component and connector in software architecture, a dynamic heuristic risk factor is obtained and severity is assessed based on hazard analysis. Then, a Markov model is constructed to obtain scenarios risk factors. The risk factors of use cases and the overall system risk factor are estimated using the scenarios risk factors. Within our methodology, we also identify critical components and connectors that would require careful analysis, design, implementation, and more testing effort. The risk assessment methodology is applied on a pacemaker case study.     

基于模糊攻防树和熵权法的工控系统脆弱性量化评估方法

为了提高脆弱性量化评估结果的可靠性,提出一种基于模糊攻防树和熵权法的工控系统脆弱性量化评估方法。该方法以攻击防御树为模型,首先将模糊集合理论与专家评价相结合,然后聚合多位专家对同一安全属模糊评价,在模糊聚合过程中利用模糊距离计算专家模糊评价的偏离度以提高模糊聚合的可靠性,并采用熵权法确定叶子节点量化过程中各安全属性的权重。最后计算叶子节点及攻击序列概率。案例分析表明,该方法能有效提高评估结果的可靠性,为工控系统信息安全防护提供重要依据。     

基于构件影响因子的软件可靠性评估方法

为提高构件式软件系统可靠性评估的准确性,使软件系统的优化效率得到提高,提出一种基于构件影响因子的软件可靠性评估方法.基于构件式软件系统具有的复杂网络特性,使用引入构件转移概率的加权PageRank算法评估构件的影响因子,将构件的影响因子引入到离散时间马尔科夫链的可靠性评估模型中,评估软件系统的可靠性.实验结果表明,该方...     

An automated software reliability prediction system for safety critical software

Software reliability is one of the most important software quality indicators. It is concerned with the probability that the software can execute without any unintended behavior in a given environment. In previous research we developed the Reliability Prediction System (RePS) methodology to predict the reliability of safety critical software such as those used in the nuclear industry. A RePS methodology relates the software engineering measures to software reliability using various models, and it was found that RePS’s using Extended Finite State Machine (EFSM) models and fault data collected through various software engineering measures possess the most satisfying prediction capability. In this research the EFSM-based RePS methodology is improved and implemented into a tool called Automated Reliability Prediction System (ARPS). The features of the ARPS tool are introduced with a simple case study. An experiment using human subjects was also conducted to evaluate the usability of the tool, and the results demonstrate that the ARPS tool can indeed help the analyst apply the EFSM-based RePS methodology with less number of errors and lower error criticality.     

Error exponents for two-hop Gaussian multiple source-destination relay channels

We investigate the two-hop multiple source-destination relay channels using the rate splitting trans-mission scheme where each source can split its message into private and public parts.We determine the system error probability via integrated exponent function under amplify-and-forward(AF)and decode-and-forward(DF)relay strategies.The most significant difference between AF and DF system error probability evaluations lies in a minimized cut-set bound of transmission rate under the DF strategy.There are many cases among transmission rate intervals for different system parameters(e.g.transmit power)and it is extremely complex to derive the system error probability for the DF strategy.We obtain a relatively simple result,which unifies various cases by a few expressions.Numerical results show that the system error probability decreases with the increase of the public message.Moreover,in order to draw deep insight into the reliability requirement of each source node in this network,we provide the error exponent region(EER)for different source nodes to show the trade-off of error probability among source nodes.     

Empirical evaluation of a privacy-focused threat modeling methodology

Privacy is a key issue in today's society. Software systems handle more and more sensitive information concerning citizens. It is important that such systems are privacy-friendly by design. In previous work, we proposed a privacy threat analysis methodology, named LINDDUN. The methodology supports requirements engineers and software architects in identifying privacy weaknesses in the system they contribute to developing. As this is a fairly new technique, its results when applied in realistic scenarios are yet unknown. This paper presents a series of three empirical studies that thoroughly evaluate LINDDUN from a multi-faceted perspective. Our assessment characterizes the correctness and completeness of the analysis results produced by LINDDUN, as well as the productivity associated with executing the methodology. We also look into aspects such as the ease of use and reliability of LINDDUN. The results are encouraging, overall. However, some areas for further improvement have been identified as a result of this empirical inquiry.     

System Test Planning of Software: An Optimization Approach

This paper extends an exponential reliability growth model to determine the optimal number of test cases to be executed for various use case scenarios during the system testing of software. An example demonstrates a practical application of the optimization model for system test planning.