Contrastive Analysis of Software Networks Based on Different Coupling Relationships

Several software network models are constructed based on the relationships between classes in the object-oriented software systems.Then,a variety of well-known open source software applications are statistically analyzed by using these models.The results show that: (1) Dependency network does play a key role in software architecture;(2) The exponents of in-degree and total-degree distribution functions of different networks differ slightly,while the exponent of out-degree varies obviously;(3) Weak-coupling relationships have greater impact on software architecture than strong-coupling relationships.Finally,a theoretically analysis on these statistical phenomena is proposed from the perspectives of software develop technology,develop process and developer’s habits,respectively.

Structural Finite Element Software Coupling Using Adapter Elements

This paper describes a versatile and computationally efficient method for coupling several finite element analysis(FEA)programs together so that the unique modeling and analysis capabilities of each code can be utilized simultaneously to simulate the static or dynamic response of a complete numerical system.An arbitrary number of finite element analysis software packages can be coupled by adding two special types of elements,namely generic and adapter elements,to each of the finite element applications using their programming interface.These elements are inserted at the interfaces between the different sub-domains of the complete system modeled by each finite element analysis software package.Exchange of data between the coupled FEA codes is accomplished in a modular and synchronized manner using OpenFresco(Opensource Framework for Experimental Setup and Control).OpenFresco is an objectoriented,environment independent software framework initially developed for hybrid simulation in which certain aspects of a complete structure are simulated numerically and other aspects are simultaneously tested physically.An important practical advantage of this coupled analysis approach is that all of the connected FEA codes run concurrently and continuously,decreasing analysis time consumption by an order of magnitude or more compared to more traditional approaches that shut down and restart the coupled analysis codes at each integration time step.The implementation and accuracy of this approach to FE software coupling are demonstrated using dynamic analyses of three simple structural models from the field of earthquake engineering.

Software Coupling and Cohesion Model for Measuring the Quality of Software Components

Measuring software quality requires software engineers to understand the system’s quality attributes and their measurements.The quality attribute is a qualitative property;however,the quantitative feature is needed for software measurement,which is not considered during the development of most software systems.Many research studies have investigated different approaches for measuring software quality,but with no practical approaches to quantify and measure quality attributes.This paper proposes a software quality measurement model,based on a software interconnection model,to measure the quality of software components and the overall quality of the software system.Unlike most of the existing approaches,the proposed approach can be applied at the early stages of software development,to different architectural design models,and at different levels of system decomposition.This article introduces a software measurement model that uses a heuristic normalization of the software’s internal quality attributes,i.e.,coupling and cohesion,for software quality measurement.In this model,the quality of a software component is measured based on its internal strength and the coupling it exhibits with other component(s).The proposed model has been experimented with nine software engineering teams that have agreed to participate in the experiment during the development of their different software systems.The experiments have shown that coupling reduces the internal strength of the coupled components by the amount of coupling they exhibit,which degrades their quality and the overall quality of the software system.The introduced model can help in understanding the quality of software design.In addition,it identifies the locations in software design that exhibit unnecessary couplings that degrade the quality of the software systems,which can be eliminated.

A metrics suite for coupling measurement of software architecture

To better evaluate the quality of software architecture,a metrics suite is proposed to measure the coupling of software architecture models,in which CBC is used to measure the coupling between components,CBCC is used to measure the coupling of transferring message between components,CBCCT is used to measure the coupling of software architecture,WCBCC is used to measure the coupling of transferring message with weight between components,and WCBCCT is used to measure the coupling of message transmission with weight in the whole software architecture. The proposed algorithm for the coupling metrics is applied to the design of serve software architecture. Analysis of an example validates the feasibility of this metrics suite.

A Metadata Model Based on Coupling Testing Information to Increase Testability of Component

A software component must be tested every time it is reused in order to assure quality of component itself and system in which it is to be integrated.So how to increase testability of component has become a key technology in the software engineering community.Here a method is introduced to increase component testability.And meanings of component testability and relative effective ways to increase testability are summarized.Then definitions of component coupling testing criterion,DU-I(Definition-Use Information) and OP-Vs(Observation-Point Values)are given.Base on these,a definition-use table is introduced,which includes DU-A and OP-Vs item,to help component testers to understand and observe interior details about component under test better.Then a framework of testable component based on above DU-table is given.These facilities provide ways to detect errors,observe state variables by observation-points based monitor mechanism.Moreover,above methods are applied to our application developed by ourselves before,and some test cases are generated.Then our method is compared with Orso method and Kan method using the same example,presenting the comparison results.The results illustrate the validity of our method,effectively generating test cases and killing more mutants.

ADTEM-Architecture Design Testability Evaluation Model to Assess Software Architecture Based on Testability Metrics

Architectural design is a crucial issue in software engineering. It makes testing more effective as it contribute to carry out the testing in an early stage of the software development. To improve software testability, the software architect should consider different testability metrics while building the software architecture. The main objective of this research is to conduct an early assessment of the software architecture for the purpose of its improvement in order to make the testing process more effective. In this paper, an evaluation model to assess software architecture (Architecture Design Testability Evaluation Model (ADTEM)) is presented. ADTEM is based on two different testability metrics: cohesion and coupling. ADTEM consists of two phases: software architecture evaluation phase, and component evaluation phase. In each phase, a fuzzy inference system is used to perform the evaluation process based on cohesion and coupling testing metrics. The model is validated by using a case study: Elders Monitoring System. The experimental results show that ADTEM is efficient and gave a considerable improvement to the software testability process.

A Component Selection Framework of Cohesion and Coupling Metrics

Component-based software engineering is concerned with the develop-ment of software that can satisfy the customer prerequisites through reuse or inde-pendent development.Coupling and cohesion measurements are primarily used to analyse the better software design quality,increase the reliability and reduced system software complexity.The complexity measurement of cohesion and coupling component to analyze the relationship between the component module.In this paper,proposed the component selection framework of Hexa-oval optimization algorithm for selecting the suitable components from the repository.It measures the interface density modules of coupling and cohesion in a modular software sys-tem.This cohesion measurement has been taken into two parameters for analyz-ing the result of complexity,with the help of low cohesion and high cohesion.In coupling measures between the component of inside parameters and outside parameters.Thefinal process of coupling and cohesion,the measured values were used for the average calculation of components parameter.This paper measures the complexity of direct and indirect interaction among the component as well as the proposed algorithm selecting the optimal component for the repository.The better result is observed for high cohesion and low coupling in compo-nent-based software engineering.

Software reliability analysis considering correlated component failures with coupling measurement framework

With progression of the digital age, the complexity of software continues to grow. AS a result, methods to quantitatively assess characteristics of software have attracted significant atten- tion. These efforts have led to a large number of new measures such as coupling metrics, many of which seek to consider the impact of correlations between components and failures on ap- plication reliability. However, most of these approaches set the coupling parameters arbitrarily by making assumptions instead of utilizing experimental data and therefore may not accurately capture actual coupling between components of software applica- tion. Since the coupling matrix is often set arbitrarily, the existing approaches to assess software reliability considering component correlation fail to reflect the real degree of interaction and rela- tionships among software components. This paper presents an efficient approach to assess the software reliability considering Correlated component failures, incorporating software architec- ture while considering actual internal coupling of software with an efficient approach based on multivariate Bernoulli （MVB） distribu- tion. The unified framework for software Coupling measurement is＇ informed by a comprehensive survey of frameworks for object- oriented and procedure-oriented software. This framework enables the extraction of more accurate coupling among cornponents. The effectiveness of this method is illustrated through an exPerimental study bylapplying it to a real-time software application.

A PAIR OF COUPLING METRICS FOR SOFTWARE NETWORKS

Complex networks are everywhere. A typical example is software network. How to measure and control coupling interactions of software components is a largely explored research problem in software network. In terms of graph theory and linear algebra, this paper investigates a pair of coupling metrics to evaluate coupling interactions between the classes of object-oriented systems. These metrics differ from the majority of existing metrics in three aspects： Taking into account the strength that one class depends on other ones, reflecting indirect coupling, and distinguishing various coupling interaction. An empirical comparison of the novel measures with one of the most widely used coupling metrics is described. Specifically, an experiment about the relationships of this pair metrics is conducted. The result shows that software complexity derived from coupling interaction could not be accurately reflected by one dimension of coupling metric for negative correlation.

Package Coupling Measurement in Object-Oriented Software

The grouping of correlated classes into a package helps in better organization of modern object-oriented software. The quality of such packages needs to be measured so as to estimate their utilization. In this paper, new package coupling metrics are proposed, which also take into consideration the hierarchical structure of packages and direction of connections among package elements. The proposed measures have been validated theoretically as well as empirically using 18 packages taken from two open source software systems. The results obtained from this study show strong correlation between package coupling and understandability of the package which suggests that proposed metrics could be further used to represent other external software quality factors.

一种横向耦合改进型结构极窄带声表面波滤波器研究

该文采用波导法分析了横向耦合极窄带声表面波滤波器速度变化模式,并用多物理场COMSOL软件对横向耦合声表面波滤波器的中心耦合条结构和耦合距离的变化建模进行计算,并分析频响特性。采用石英晶体作为底衬,设计了频率为898.144 MHz,插入损耗约为6 dB的极窄带声表面波滤波器并进行验证。结果表明,中心耦合条开腔结构的声表面波滤波器的相对带宽达到7.2‰,与不开腔结构5.2‰相对带宽相比,提升了2‰。这说明横向耦合声表面波滤波器的中心耦合条结构变化,能改变极窄带声表面波滤波器的相对带宽。

航天型号综合测试软件的可重用架构设计方法

针对航天型号综合测试软件研制周期短、定制化程度高、调试过程复杂等特点,通过提炼共性需求,提出了一种基于操作系统的可重用架构设计方法。该方法采用分层架构设计模式,驱动层在操作系统接口约束下实现了对不同硬件的统一访问,框架层采用“流程范式+功能组件”模式实现软件的核心功能,应用层则通过配置快速搭建测试场景。该架构已在多种类型的航天装备中验证应用,结果表明该架构显著缩短了软件开发时间,降低了开发成本,提升了软件的可靠性和扩展性,对航天软件的研制具有重要的实用价值和借鉴意义。

基于分层软总线的新型通用操作系统结构模型

传统的操作系统设计所面临的主要挑战是需要管理的资源数量,多样性,分布范围不断增加以及系统状态频繁变化.然而,现有操作系统结构已经成为应对上述挑战的最大障碍,原因如下:(1)紧耦合和中心化的结构不仅损害了系统的灵活性和扩展性,还导致了操作系统生态分离;(2)系统中单一的隔离机制,如内核态-用户态隔离,造成了各种能力之间的矛盾,如安全性和性能等.为此,结合简捷的分层软总线设计思想和多样化隔离机制来组织操作系统组件,提出一种新型操作系统模型——Yggdrasil.Yggdrasil将操作系统功能分解为以软总线相连接的组件节点,其通信被标准化为经软总线的消息传递.为支持特权态等隔离状态的划分和不同的软件层次,Yggdrasil还引入桥节点实现多层软总线的级联和受控通信,通过自相似的拓扑特性使操作系统的逻辑表述能力和扩展性都得到了极大的强化.此外,软总线的简单性和层次性也有助于实现去中心化.构建操作系统的分层软总线模型实例HiBuOS,通过3方面的具体设计验证并展示基于Yggdrasil思想来开发新型操作系统的可行性:(1)根据目标操作系统的规模和要求设计规划多层总线结构;(2)选择具体的隔离和通信机制实例化桥节点和软总线;(3)实现基于分层软总线风格的操作系统服务.对HiBuOS的评估表明,它没有引入明显的性能损耗,而且还在提高系统可扩展性,安全性和生态发展方面具有显著的优势和潜力.

基于MIKE+的南昌市朝阳片区内涝定制化动态模拟软件开发

对于管理决策者而言,目前普遍使用的城市内涝动态模拟软件均存在学习成本大、操作不方便且展示结果繁多等问题,为降低模拟软件的使用门槛、简化其操作方式并突出重点结果的展示,以南昌市朝阳片区为例,利用MIKE+综合水模拟软件构建了研究区域的城市内涝耦合模型,在此基础上使用Axure、Vue3、JavaScript等软件为管理决策者设计开发出一套具有定制化功能设计、结果展示的城市内涝动态模拟软件。实例应用结果表明,该软件在功能实现、模拟精度、结果展示及运行稳定性方面均达到了预期目标,且操作方式遵循易用性原则,便于管理决策者使用,可有效辅助制定防汛排涝策略,提高了南昌市内涝风险管理数字化水平,并可为其他地区提供借鉴。

紧凑型槽式太阳能集热器与建筑用能匹配特性分析

我国建筑能耗占全国总能耗约40%,将太阳能与建筑相结合,可有效降低建筑能耗对化石能源的依赖,助力“双碳”目标实现。基于一种紧凑型热管真空管槽式集热器,设计了吸收式制冷空调系统,并与地源热泵集成,构建了多能互补耦合供能系统。首先,对比分析紧凑型热管真空管槽式集热器与普通真空管式集热器的集热性能;然后,以某600 m^(2)建筑物为供能对象,在TRNSYS软件中搭建太阳能空调系统,对该建筑进行供能;最后,搭建多能互补供能系统,提升整体供能效率。结果表明:该紧凑型热管真空管槽式集热器与普通真空管式集热器相比,集热温度提升25%,集热面积减少52.5%,集热量提升2.5倍。多能互补太阳能空调系统能极大改善太阳能系统与季节的匹配性,满足建筑物全年的供能需求及热水供应。该系统对太阳能与建筑一体化研究以及建筑供能研究有良好的参考价值。

基于Fluent的IGBT模块散热器的优化设计

随着新能源电动汽车功率控制器中的IGBT模块向着微型化、集成化方向发展,功率密度增大会导致芯片发热量大幅度增加,降低模块的可靠性。优化英飞凌IGBT模块的散热器结构,以提高散热器的散热性能。设计开口角度为63.256°供冷却液流通的进口和出口,在散热器前、中、后位置设计直径为4~5.5 mm、叉分式排布的扰流柱。利用ANSYS仿真软件,通过计算流体动力学(CFD)的流固耦合传热计算模型进行仿真分析。仿真结果表明,采用新型叉分式结构散热器的IGBT模块的最高温度为85.10℃,最低温度为65.28℃,平均温度为78.81℃,均低于传统均分式结构散热器模块。搭建实验平台对IGBT模块散热器的散热性能进行检测,实验结果表明新型叉分式结构散热器散热效果良好,有助于提升IGBT模块的可靠性。

一种基于耦合关系搜索的更改影响评估方法

问题报告和更改控制是DO-178C对民用飞机机载软件配置管理过程的基本要求,而更改影响分析则一直是机载软件更改控制过程中的一项难点问题。对更改影响分析的不彻底可能造成受影响软件部件的不正常运行,对军用飞机和民用飞机机载设备安全性的影响不容忽略。为了快速、有效地定位机载软件更改后对其它软件单元和相关软件生命周期资料的影响,使用有向图将软件单元之间的耦合关系进行抽象,并针对有向图的节点和边设计相关数据结构进行数字化存储,使用逆向搜索的方式对有向图数据进行遍历搜索,快速量化软件原始更改所带来的潜在影响。

基于一体式S波段陶瓷介质滤波器的研究

引用CST三维电磁仿真软件提出了一种三阶介质滤波器的设计方法。通过源与第二谐振器或负载与第三谐振器构成级联三节(CT)交叉耦合结构产生传输零点的方式,满足更高频率端的高抑制要求。第二谐振器与第三谐振器开路端电极相连,形成三阶滤波器结构实现了低损耗性能。4个谐振器短路端被缩短,从而扩大了电极可调试区域以简化滤波器的调试复杂度。一体式介质滤波器采用介电常数为45.9的陶瓷材料制作样品并进行测试。测试结果表明,所设计的介质滤波器1 dB带宽为117 MHz,通带频率范围2084~2104 MHz的插入损耗(IL)小于1.2 dB,通带驻波比小于1.28,高端频率2.2 GHz处的衰减为34.35 dB,低端频率1.6 GHz处的抑制为31.04 dB,滤波器外形尺寸为10.41 mm×3.7 mm×4.57 mm。测试结果与仿真结果吻合度高。

柠条塔煤矿采煤围岩渗透性变化规律及工作面涌水量预测

煤矿开采围岩渗透性变化对工作面涌水量预测精度具有重要作用。本文以柠条塔煤矿顶板砂岩为研究对象,采用FLAC3D软件流固耦合模块模拟分析了围岩的水平渗透系数和垂直渗透系数变化规律,以此为基础,采用地下水模拟系统预测分析了S12003工作面的涌水量。研究结果表明:当工作面推进距离为100 m、200 m、300 m和400 m时,水平渗透系数最大分别增大约10倍、500倍、10000倍和1000000倍,垂直渗透系数最大分别增大约5倍、50倍、100倍和10000倍。对于不同的部位,其水平渗透系数和垂直渗透系数变化规律不一致。随着工作面推进距离的增加,孔隙水压力降至0 MPa的范围及覆岩上部发生塑性破坏的范围均呈现逐步增大的趋势。以此为基础,预测的工作面涌水量呈现随工作面推进先逐步增加后有所减少趋势,最终工作面涌水量基本稳定在210 m3/h左右。此时,上覆直罗组承压含水层的静储量基本已经疏干,工作面的涌水主要为含水层的侧向补给。预测结果与实际情况相符合。研究成果可为类似条件下的工作面涌水量预测提供参考。

COMSOL中挠曲电圆筒的力电耦合行为分析

针对目前商业有限元软件中缺少挠曲电模块且有限元自主编程数值模拟挠曲电问题的复杂性问题,提出在COMSOL软件中的偏微分方程模块(PDE模块),对考虑挠曲电效应的力电耦合问题直接进行数值模拟的方法.首先,通过数值计算固定边界位移的挠曲电圆筒,验证有限元数值计算方法的正确性.接着,研究挠曲电系数和不同材料梯度指数对圆筒力电耦合的影响.数值结果表明:在微米尺度下,增大挠曲电系数对径向位移的影响很小,但是对圆筒内部的电势和电位移分布影响很大.增大材料梯度指数对挠曲电圆筒内部力电耦合影响非常明显,圆筒内部径向位移相对边界处变化范围逐渐减小,圆筒内部电势呈现负值逐渐减小后转为正数的趋势,而圆筒内部电位移值负值逐渐增大.本工作可以为挠曲电效应数值计算及挠曲电结构设计提供帮助.