SUMMARY Software maintenance including design is difficult because it is usually performed on someone else's work over a period of time. Maintaining a pattern‐based design is especially much more difficult when the information on specific patterns that have been used are not available in the corresponding design documents. Also, finding a maintainer who has a similar level of knowledge on specific patterns that the initial designer had is not easy. Pattern‐based design, the use of design patterns during the software design process, has become widely used in the object‐oriented community because of its many benefits such as its reuse. However, the defects in pattern‐based design can be introduced during the design maintenance phase when the changes are made to the requirements and the initial design, but the conformance to the original patterns is neglected. This conformance process is laborious and time consuming; no systematic process exists to guide the defects discovery and maintenance. Also, deep and correct knowledge of design patterns and their characteristics are required because this process is conducted by human experts. Failure to follow this conformance process and to maintain correct designs during software design evolution may cause serious problems in later software development and maintenance stages by not providing the benefits of pattern‐based design that would have been possible if followed correctly. There is a strong need of a systematic design and maintenance method for preventing defects in design patterns introduced during the evolution of pattern‐based software design and its maintenance. Because conventional UML design methods do not provide such systematic ways of assessing pattern‐based design conformance to the evolutionary changes, we have developed the pattern instance changes with UML profiles (PICUP) design method, which is an improved design method for perfective and corrective UML pattern‐based design maintenance and assessment. Design pattern in UML profiles (DPUP) is developed for the use of instantiation, maintenance, and assessment of UML pattern‐based designs to support the formal specification of a design pattern. DPUPs, as the main part of the PICUP design method, provide metamodel‐level UML design constraints using UML stereotype notations and metamodel‐level Object Constraint Language design constraints. Assessment of pattern‐based designs in UML class diagram with the corresponding DPUPs enforces maintainers to make necessary and correct changes to keep the principles of the original designs. Pattern‐related information is annotated using stereotype notations to help assess pattern‐based designs when changes are made. Furthermore, the structural conformance checking of a given UML pattern‐based design can be automated by using the assessment tool. The major contributions of this paper are: (i) specifying design patterns using extended UML profile; (ii) providing a means of how to instantiate pattern‐based designs from DPUPs with naming conventions; and (iii) providing design constraints for maintaining pattern‐based design to guide correct changes of a given design in PICUP method. Explanatory type case studies were performed to better understand and evaluate the effectiveness of the PICUP design method with DPUPs. Answers to the case study questionnaires and the pattern defects discovered from the case studies support the hypothesis that the PICUP method is an improved design method that ensures structural conformance of UML pattern‐based designs to the corresponding design patterns during perfective and corrective design maintenance for software systems. Copyright © 2011 John Wiley & Sons, Ltd.

Accurate estimation of the software effort and schedule affects the budget computation. Bidding for contracts depends mainly on the estimated cost. Inaccurate estimates will lead to failure of making a profit, increased probability of project incompletion and delay of the project delivery date. In this paper, we explore the use of Soft Computing Techniques to build a suitable model structure to utilize improved estimations of software effort for NASA software projects. In doing so, we plan to use Particle Swarm Optimization (PSO) to tune the parameters of the famous COnstructive COst MOdel (COCOMO). We plan also to explore the advantages of Fuzzy Logic to build a set of linear models over the domain of possible software Line Of Code (LOC). The performance of the developed model was evaluated using NASA software projects data set [1]. A comparison between COCOMO tuned-PSO, Fuzzy Logic (FL), Halstead, Walston-Felix, Bailey-Basili and Doty models were provided.

The structural stability of an object-oriented design (OOD) refers to the extent to which the structure of the design is preserved throughout the evolution of the software from one release to the next. This paper empirically investigates potential indicators of measures of structural stability of OODs. Both product-related and process-related indicators are considered. These indicators were evaluated through a case study that involves 13 successive releases of Apache Ant. The results showed that each one of the stability metrics is significantly correlated with at least one of the investigated indicators. To make early predictions of the values of each one of the stability metrics, statistically significant regression models were constructed from subsets of the investigated indicators

The Java Cryptography Architecture, JCA in short, was created to allow JCA-compliant cryptography providers to be plugged into a JCA-aware application at run time. This configurable feature makes JCA widely used and assures its success. However, the public key cryptographic service interfaces defined by JCA are based on the conventional public key cryptography, which is a single-sender-single-receiver model, and does not accommodate the group-based public key cryptography well. Especially, it does not support the threshold cryptography (TC), an important type of group-based public key cryptography, which has been shown to be a useful tool to enhance system security. As a step towards the systematic application of group-based public key cryptography, this article proposes an extension to the JCA framework to integrate threshold cryptography. Under this extension, various TC providers implementing different TC primitives can be plugged into a security application at run-time. This extension also makes it easy for a existing JCA-aware application to be migrated to use threshold cryptography. An example provider of threshold RSA is implemented under this framework extension. It is our belief that such an extension would help speed up the adoption of threshold cryptography.

In this paper, neural networks have been proposed as an alternative technique to build software reliability growth models. A feedforward neural network was used to predict the number of faults initially resident in a program at the beginning of a test/debug process. To evaluate the predictive capability of the developed model, data sets from various projects were used. A comparison between regression parametric models and neural network models is provided.

Domain Name System (DNS) is the system for the mapping between easily memorizable host names and their IP addresses. Due to its criticality, security extensions to DNS have been proposed in an Internet Engineering Task Force (IETF) working group to provide authentication. We point out two difficulties in the current DNSSEC (DNS Security Extension) standards in the handling of DNS dynamic updates: the online storage of a zone security key, creating a single point of attack for both inside and outside attackers; and the violation of the role separation principle, which in the context of DNSSEC separates the roles of zone security managers from DNS server administrators. To address these issues, we propose a secure DNS architecture that is based on threshold cryptography. We show that the architecture adheres to the role separation principle without presenting any single point of attack. Our experimental results reveal that, in terms of signature computation times, our architecture incurs negligible performance penalty when using RSA/MD5 signatures but significant overhead when using DSA signatures. It is our belief that the high level of security that can be achieved by the proposed architecture far outweighs its potential overhead, especially in critical DNS zones, such as the .com zone.

The contribution of this paper is a reference model for the practice of software reuse. Our research thesis is that software development based upon a software reuse reference model improves quality of products, productivity of processes and product time-to-market for many software development enterprises. The definition and investigation of such a model has been carried out using three steps. First, the reference model is developed based on existing software reuse concepts. Second, this reference model is empirically studied using both legacy studies and lessons learned studies. Third, the impact of the reference model on software development productivity, quality, and time-to-market is empirically derived. Copyright © 2000 John Wiley & Sons, Ltd.

Command, control, communications, computers, and intelligence (C/sup 4/I) systems are used to assist organizations in achieving their respective goals and objectives. Although organizations are becoming increasingly more dependent on C/sup 4/I systems, there is a lack of automated tools for carrying out the planning functions inherent in C/sup 4/I systems. The paper presents a framework for agent based C/sup 4/I systems. The paper presents an approach and issues for developing such C/sup 4/I systems.

Information distribution rules (IDRs) can be utilized to effectively and efficiently control event-driven information flow between objects in distributed-object systems. The problem with IDRs is that as the configuration of the distributed system gets larger (i.e., large number of objects, large number of possible events, more need for information, large number of communication constraints, etc.), it is very difficult to generate and debug IDRs manually. Additionally, having faulty IDRs can lead to serious undesirable situations. This paper presents an algorithm to generate near-optimal IDRs for efficient and effective information flow. Illustrative examples as well as complexity analysis of the behaviour of this algorithm are included in the paper.

Abstract We investigate how a formalism, common to many areas of applied mathematics and engineering, known as a basis can be applied to perfective maintenance and integration in software engineering, using an object‐oriented approach. It is concluded that this formalism serves as a mathematical model for perfective software maintenance and integration activities. Theorems and properties about the model are reported as guides to software maintenance. The model and formal maintenance techniques have been applied to a software system in the management information systems area to demonstrate this approach to perfective maintenance and to assist in validating the model.

Abstract Recent research on software development environments (SDE) and computer‐aided software engineering (CASE) have not addressed the issue of multiple environments. This paper presents an approach for developing an integrated modelling environment (IME) that supports the maintenance of software environment models in software engineering. The approach uses the notion of a composite software development environment maintaining multiple software development environments. The composite is specified by analysing and identifying common features from other environments. These other environments include various government‐supported efforts. The idea of a common software development environment may be supported in part by several different international standards or technical approaches (e.g. CAIS, CAIS‐A, PCTE, ALMA/metasystems, object‐oriented systems, and so forth). Some of these ways are outlined in the paper. An analysis of them in case study form is presented.

The Advanced Placement Program in Computer Science will be discussed by members of the development group. The presentation will be geared to both high school and college level educators.

No abstract available.

“A National Educational TV Series at Pre-College Level for Personal Computing and Computer Literacy”, David C. Rine, Western Illinois University.

This paper summarizes a study which was made by the authors on the various roles of personal computing in early education, college education and continued education of the individual.The role of personal computing in continued education is decomposed into its specific roles in the reeducation of business persons (especially small businesses), of computer professionals, and of educators and other users of personal computing.It is pointed out that among many professional societies today, as well as within the total education of the individual, personal computing is an essential topic of national and international concern.

Competency In Computer Instruction In Illinois Public Schools.

This paper is a progress report from the IEEE Computer Society's Subcommittee on Model Curricula in Software Engineering. Both undergraduate and graduate curricula are discussed, and the current status of the effort is summarized. Some of the problems that remain to be solved are mentioned. The paper describes work in progress and should not be considered a final document.

The role of the computer in engineering practice is ever increasing. The computer performs such tasks as: simple calculations; on line data recording and synthesis; acting as a control unit providing feedback; statistical analysis of large data sets; information retrieval and storage; and the simulation of large complex systems.

Four commonly used multivalued algebras, the disjoint system of Post algebra developed by Epstein, the monotonic system of algebra called Muehldorf by some authors, the free system of algebra introduced by Braddock and Epstein, and the Herrmann system of algebra generalized here from its original three element algebra, are shown to be isomorphic. Transformations are then developed for transforming from one algebra to another. An example problem is presented to illustrate transforming from any of the above to the disjoint system of Post algebra.