基于组件的嵌入式软件开发方法

根据嵌入式软件的特点,提出一种以模型为中心、基于组件的嵌入式软件开发方法。它以动态数据流图为系统模型对嵌入式软件的功能和性能需求进行了描述,由此提供了强大的描述和分析能力;通过基于特定组件模型的实现结构和实现代码框架的自动生成,以DDF定义的系统可以被有效地分解为一系列独立的组件,合适的DDF调度算法一致地表示了系统组件的执行语义,使得并发开发的组件具有良好的可集成性。该方法充分考虑了嵌入式开发的特点,能有效地降低系统复杂性和支持系统组件的并发开发和复用,从而提高了开发效率并降低了开发成本。     

Towards a visual approach for component-based software development

The ever increasing emphasis on distributed systems has led to advances in the client/server model and the emergence of component-based software development as an important paradigm in software engineering. Along with the new computer technologies it is necessary to reuse legacy code. Approaches to application development over, for example, the Internet are important if this is to be successful. This paper examines these issues and argues that incorporating the ideas of the component-based approach and reuse can significantly assist the application software developer. It demonstrates an approach through the development of an interactive/visual environment for component-based assembly.     

A novel approach for component-based fault-tolerant software development

With the recent advancements in component-based software engineering, there is an increasing trend in developing applications for highly reliable and critical systems using pre-validated and reusable software components. As these applications are inherently complex and component-interactions are not straightforward, there is an immediate need for a methodology that could aid in composition of these reusable components ensuring the correctness of the composed software system. In this paper, we illustrate how the concepts of category theory can be utilized to develop component-based fault-tolerant software systems that encompass software components capable of tolerating particular types of faults. Our proposed framework for the development of a composite fault-tolerant program and verification of its overall correctness has been realized through a mechanized formal tool.     

基于组件的非线性软件开发过程研究

探讨了通过软件企业的组织结构再造和软件开发流程再造,实现基于组件的非线性软件开发过程的研究。     

A design flow for supporting component-based software development in multiprocessor real-time systems

Component-based software development established as an effective technique to cope with the increasing complexity of modern computing systems. In the context of real-time systems, the M-BROE framework has been recently proposed to efficiently support component-based development of real-time applications on multiprocessor platforms in the presence of shared resources. The framework relies on a two-stage approach where software components are first partitioned upon a virtual multiprocessor platform and are later integrated upon the physical platform by means of component interfaces that abstract from the internal details of the applications. This work presents a complete design flow for the M-BROE framework. Starting from a model of software components, a first method is proposed to partition applications to virtual processors and perform a synthesis of multiple component interfaces. Then, a second method is proposed to support the integration of the components by allocating virtual processors to physical processors. Both methods take resource sharing into account. Experimental results are also presented to evaluate the proposed methodology.     

Automatic generation algorithm of expected results for testing of component-based software system

ContextA component-based software (CBS) system is a typical example of a composite component, which is composed of two or more atomic components. In the test of a CBS system, it is necessary to automatically generate expected results because they are compared with the actual results.ObjectiveThis paper proposes an automatic generation algorithm of expected results for the testing of a CBS system.MethodThe algorithm analyzes Input/Output (I/O) relationships of a CBS system to identify inputs that influence its outputs. Then, the algorithm uses test cases of atomic components for each input and automatically generates expected results. To evaluate the proposed approach, we compare the proposed approach with the other I/O relationship based approach via two case studies which are the CBS systems for guide robot. The comparison shows the effectiveness of our approach.ResultsTo verify effectiveness of the proposed approach, we measure the cost of manual generation of expected results for each case study. The costs are from 0.001 to 0.015 in the first case study, and are from 0.590 to 0.998 in the second case study.ConclusionThis proposed approach reduces the time-consuming and error-prone task which manually generates expected results for the testing of a CBS system.     

Multiple-parameter coupling metrics for layered component-based software

Coupling represents the degree of interdependence between two software components. Understanding software dependency is directly related to improving software understandability, maintainability, and reusability. In this paper, we analyze the difference between component coupling and component dependency, introduce a two-parameter component coupling metric and a three-parameter component dependency metric. An important parameter in both these metrics is coupling distance, which represents the relevance of two coupled components. These metrics are applicable to layered component-based software. These metrics can be used to represent the dependencies induced by all types of software coupling. We show how to determine coupling and dependency of all scales of software components using these metrics. These metrics are then applied to Apache HTTP, an open-source web server. The study shows that coupling distance is related to the number of modifications of a component, which is an important indicator of component fault rate, stability and subsequently, component complexity.

构件软件的可靠性估算模型

把基于构件的软件看作是一个Markov过程,为弥补以往忽视连接件作用的情况,针对过程中不同状态类型,构建出基于不同状态的构件和连接件使用频率计算模型。在此基础上,提出了整个基于构件的软件可靠性计算方法,并将其实例化。与传统的方法相比,该方法不仅提供了一种更精确分析软件可靠性的方法,而且拓宽了模型的应用范围。     

Using components for rapid distributed software development

Software development has not reached the maturity of other engineering disciplines; it is still challenging to produce software that works reliably, is easy to use and maintain, and arrives within budget and on time. In addition, relatively small software systems for highly specific applications are in increasing demand. This need requires a significantly different approach to software development from that used by their large, monolithic, general-purpose software counterparts such as Microsoft Word. The paper discusses the use of components for rapid distributed software development. It reports on the the experience of a large testbed called Educational Software Components of Tomorrow (www.escot.org), supported by the US National Science Foundation     

A Component-Based Software Configuration Management Model and Its Supporting System

Software configuration management(SCM)is an important key technology in software development.Component-based software development (CBSD)is an emerging paradigm in software development.However,to apply CBSD effectively in real world practice,supporting SCM in CBSD needs to be further investigated.In this paper,the objects that need to be managed in CBSD is analyzed and a component-based SCM model is presented.In this model,Components,as the integral logical constituents in a system,are managed as the basic configuration items in SCM,and the relationships between/among components are defined and maintained.Based on this model.a configuration management system is implemented.     

组件化模具PDM系统的组件结构与规划

对组件进行系统合理地规划是基于组件技术开发PDM系统的PDM系统提出了更高的要求.为此,从系统规划的角度提出了组件化模具PDM系统的组件层次体系结构,对系统组件进行了详细地划分,最后引入GenVoca模型对组件间关系进行形式化描述,保证了组件之间逻辑关系的正确性.     

构件化安全苛求软件的安全接口策略

在采用构件化技术的安全苛求软件中,软件的安全性仍旧是首要特性,介绍了多故障模式下的安全接口策略,并将此理论应用在铁路车站计算机联锁软件这种安全苛求软件的开发中,对系统中单个构件定义安全接口,从而为整个软件系统提供了有效的安全性保障。     

A component-based process with separation of concerns for the development of embedded real-time software systems

Numerous component models have been proposed in the literature, a testimony of a subject domain rich with technical and scientific challenges, and considerable potential. Unfortunately however, the reported level of adoption has been comparatively low. Where successes were had, they were largely facilitated by the manifest endorsement, where not the mandate, by relevant stakeholders, either internal to the industrial adopter or with authority over the application domain. The work presented in this paper stems from a comprehensive initiative taken by the European Space Agency (ESA) and its industrial suppliers. This initiative also enjoyed significant synergy with interests shown for similar goals by the telecommunications and railways domain, thanks to the interaction between two parallel project frameworks. The ESA effort aimed at favouring the adoption of a software reference architecture across its software supply chain. The center of that strategy revolves around a component model and the software development process that builds on it. This paper presents the rationale, the design and implementation choices made in their conception, as well as the feedback obtained from a number of industrial case studies that assessed them.     

A validation of the component-based method for software sizeestimation

Estimation of software size is a crucial activity among the tasks of software management. Work planning and subsequent estimations of the effort required are made based on the estimate of the size of the software product. Software size can be measured in several ways: lines of code (LOC) is a common measure and is usually one of the independent variables in equations for estimating several methods for estimating the final LOC count of a software system in the early stages. We report the results of the validation of the component-based method (initially proposed by Verner and Tate, 1988) for software sizing. This was done through the analysis of 46 projects involving more than 100,000 LOC of a fourth-generation language. We present several conclusions concerning the predictive capabilities of the method. We observed that the component-based method behaves reasonably, although not as well as expected for “global” methods such as Mark II function points for software size prediction. The main factor observed that affects the performance is the type of component     

用于软件选型的度量模型及系统实现

针对现有软件选型手段存在的缺乏统一标准、主观性和片面性较强的问题,建立了软件选型过程模型,设计了基于模糊综合评价的软件选型度量模型,讨论了软件选型度量模型的三个层次,进而开发了可操作的软件选型度量原型系统,并通过实验验证了该系统的有效性。     

Traditional, iterative, and component-based development: A social analysis of software development paradigms

Information systems have always been developed through social processes, wherein actors playing a variety of specialized roles interact to produce new business applications of information technology. As systems development practices continue to evolve, an ongoing assessment of their social implications is required. This paper develops a framework for understanding the potential social implications of an emerging, component-based development paradigm. Like two alternative paradigms for systems development, the traditional life-cycle and the iterative-incremental paradigms, the new component-based paradigm requires that certain generic roles be performed to build a desired application. For each paradigm, we identify the actors who play different roles, specify the nature of their interdependence, and indicate the requirements for managing conflicts constructively. The framework may guide research into the social dynamics of system development and serve as a tentative guide to the management of information systems development.     

Reengineering component-based software systems with Archimetrix

Many software development, planning, or analysis tasks require an up-to-date software architecture documentation. However, this documentation is often outdated, unavailable, or at least not available as a formal model which analysis tools could use. Reverse engineering methods try to fill this gap. However, as they process the system’s source code, they are easily misled by design deficiencies (e.g., violations of component encapsulation) which leaked into the code during the system’s evolution. Despite the high impact of design deficiencies on the quality of the resulting software architecture models, none of the surveyed related works is able to cope with them during the reverse engineering process. Therefore, we have developed the Archimetrix approach which semiautomatically recovers the system’s concrete architecture in a formal model while simultaneously detecting and removing design deficiencies. We have validated Archimetrix on a case study system and two implementation variants of the CoCoME benchmark system. Results show that the removal of relevant design deficiencies leads to an architecture model which more closely matches the system’s conceptual architecture.     

A component-based approach to telecommunication software

This article discusses a domain-specific component-based architecture called distributed feature composition. Based on the well-known pipe-and-filter architecture, DFC has been refined for use in the telecommunication domain. The authors also point to ways this approach might work in other domains, including data networks