Evaluation of Embedded Operating System by a Software Method

In this paper, software faults are emulated by Software Implemented Fault Injection （SWIFI） to evaluate embedded operating system. The method is based on the fact that the source codes of the operating system arc mapped into the code segment in the target memory and it is easy to inject kinds of faults in the memory by SWIFI. Faults are emulated by injecting faults at assembly level instead of source code bevel. Using the software faults emulated by this method, the dependability of an embedded operating system is studied. The experimental results show that software faults have many effects on the software behavior and dependability, and to increase the dependability of software, exclusion of software faults is very important.     

Software structure evaluation based on the interaction and encapsulation of methods

Software structure is the most important factor affecting the quality of a program.The evaluation of software structure is a foundational technique for software development.However,the traditional evaluation criteria,such as "high cohesion and low coupling",are no longer appropriate for the new web applications,which are designed with a hierarchical framework.A novel approach is proposed in this paper to evaluate software quality based on the interaction and encapsulation of methods.In particular,two criteria for high quality software,the functional and hierarchical structure,are proposed to support widely used web applications.The cohesion and coupling and layer matching ratios between methods within a software package are calculated to determine whether the package is well implemented in terms of functional or hierarchical structure.This approach enables us to quantify the quality of a software system according to the structural types of its packages.Experiments were carried out on 18 versions of Struts and six open-source software packages.Our evaluation concurs with the intuition that minor upgrades,aimed at fixing bugs and adding minor functionality quickly,reduce software quality,whereas major upgrades,which normally clean up messy code and re-construct the software,improve software quality.     

A Model for Slicing JAVA Programs Hierarchically

Program slicing can be effectively used to debug, test, analyze, understand and maintain objectoriented software. In this paper, a new slicing model is proposed to slice Java programs based on their inherent hierarchical feature. The main idea of hierarchical slicing is to slice programs in a stepwise way, from package level, to class level, method level, and finally up to statement level. The stepwise slicing algorithm and the related graph reachability algorithms are presented, the architecture of the Java program Analyzing TOol (JATO) based on hierarchical slicing model is provided, the applications and a small case study are also discussed.     

Structured Development Environment Based on the Object-Oriented Concepts

The object oriented software development is a kind of promising software methodology and leading to awholly new way for solving problems. In the research on the rapid construction of Structured Development Envi-ronment (SDE)that supports detailed design and coding in software development, a generator that can gener-ate the SDE has been applied as a metatool. The kernel of SDE is a syntax-directed editor based on the ob-ject-oriented concepts. The key issue in the design of SDE is how to represent the elements of target languagewith the class concept and a program internally. In this paper, the key concepts and design of the SDE and itsgenerator as well as the implementation of a prototype are to be discussed.     

Eliciting dependability requirements: a control cases based approach

At present,great demands are posed on software dependability.But how to elicit the dependability requirements is still a challenging task.This paper proposes a novel approach to address this issue.The essential idea is to model a dependable software system as a feedforward-feedback control system,and presents the use cases+control cases model to express the requirements of the dependable software systems.In this model,while the use cases are adopted to model the functional requirements,two kinds of control cases(namely the feedforward control cases and the feedback control cases)are designed to model the dependability requirements.The use cases+control cases model provides a unified framework to integrate the modeling of the functional requirements and the dependability requirements at a high abstract level.To guide the elicitation of the dependability requirements,a HAZOP based process is also designed.A case study is conducted to illustrate the feasibility of the proposed approach.     

Structured Development Environment Based on the Object-Oriented Concepts

The object-oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems.In the research on the rapid construction of Structured Development Environment(SDE)that supports detailed design and coding in software development,a generator that can generate the SE has been applied as a metatool.The kernel of SDE is a syntax-directed editor based on the object-oriented concepts.The key issue in the design of SDE is how to represent the elements of target language with the class concept and a program internally.In this paper,the key concepts and design of the SDE and its generator as well as the implementation of a prototype are to be discussed.     

双专业复合型软件工程课程体系的研究与实践(英文)

With IT technology continues to penetrate to other industries,the industry of information technology is becoming the focus of IT companies for business.The urgent need for industry information is the compound software talents who will both have strong project management skills,good technical background and fast learning ability.To this end,Dalian Jiaotong University,based on integrating information technology and its application in different areas,initiated the dual professional compound training model of "traditional professional + software engineering" in 2001 in the country.The aim for this model is to train software talents who are compound,practical and the international competitiveness.This paper focuses on the depth discussion of dual professional compound software engineering curriculum,and analyzes the need for reform of dual professional compound software engineering curriculum,then combines with IT industry needs and the actual situation in the school to put forward practical curriculum reform program.     

A cost effective fault-tolerant scheme for RAIDs

The rapid progress in mass storage technology has made it possible for designers to implement large data storage systems for a variety of applications.One of the efficient ways to build large storage systems is to use RAIDs only when one error occurs .But in large RAIDs systems ,the fault probability will increase when the number of disks increases ,and the use of disks with big storage capacity will cause the recovering time to prolong,thus the probability of the second disk‘‘‘‘‘‘‘‘s fault will incerease Therefore,it is necessary to develop methods to recover data when two or more errors have occurred In this paper,a fault tolerant scheme is proposed based on extended Reed-Solomon code,a recovery procedure is designed to correct up to two errors which is implemented by software and hardware together,and the scheme is verified by computer simulation,In this scheme,only two redundant disks are used to recover up to two disks‘‘‘‘‘‘‘‘ fault .The encoding and decoding methods,and the implementation based on software and hardware are described.The application of the scheme in software RAIDs that are builit in cluster computers are also described .Compared with the existing methods such as EVENODD and DH ,the proposed scheme has distinct improvement in implementation and redundancy.