International Journal of Software Engineering and Knowledge Engineering

Expert-based effort prediction in software projects can be taught, beginning with the practices learned in an academic environment in courses designed to encourage them. However, the length of such courses is a major concern for both industry and academia. Industry has to work without its employees while they are taking such a course, and academic institutions find it hard to fit the course into an already tight schedule. In this research, the set of Personal Software Process (PSP) practices is reordered and the practices are distributed among fewer assignments, in an attempt to address these concerns. This study involved 148 practitioners taking graduate courses who developed 1,036 software course assignments. The hypothesis on which it is based is the following: When the activities in the original PSP set are reordered into fewer assignments, the result is expert-based effort prediction that is statistically significantly better.

In this paper challenges of using Knowledge Engineering methods in the Software Engineering practice, with focus on the visual design methods for software applications, are discussed. The paper concerns practical design issues of rule-based models integrated with business applications built using the Model-View-Controller (MVC), or equivalent architectural pattern. The Unified Modeling Language (UML) constitutes a standardized notation among software engineers. Various attempts has been made to design the model in a way alternative to UML. Recently, the Business Rules approach has been proposed as a new way of capturing the functional requirements in a designer-friendly fashion. However, concepts on which the rule-based representation is based cannot be directly modeled in UML, because the semantics of UML diagrams does not correspond to rule semantics. Our research considers a method of designing rule bases which will be proper and consistent with the UML design. The approach has several important features: the core logic of the application is clearly identified and separated, and it is built in a declarative way, which makes the design transparent, easier to follow and develop. When rules are used to model the application logic, one has to keep in mind some common and well-known limitations of the existing rule tools. Our solution to these problems consists of using an expressive visual rule design formalism called XTT2, defining a direct translation between XTT2 and selected UML diagrams, implementing practical translators between the logical model and MOF-based UML model, and using the verification features provided with the XTT2 framework to assure the quality of the rule base. This solution seems to be superior both to existing visual UML rule notations, as well as visual design tools for rules. It does not extend any custom UML artifacts and can be used with standard UML tools.

We present an analysis of the evolution of a Web application project developed with object-oriented technology and an agile process. During the development we systematically performed measurements on the source code, using software metrics that have been proved to be correlated with software quality, such as the Chidamber and Kemerer suite and Lines of Code metrics. We also computed metrics derived from the class dependency graph, including metrics derived from Social Network Analysis. The application development evolved through phases, characterized by a different level of adoption of some key agile practices — namely pair programming, test-based development and refactoring. The evolution of the metrics of the system, and their behavior related to the agile practices adoption level, is presented and discussed. We show that, in the reported case study, a few metrics are enough to characterize with high significance the various phases of the project. Consequently, software quality, as measured using these metrics, seems directly related to agile practices adoption.

The end users' expectations for the software services are increasing. With new technologies, e.g. cloud computing and software as a service trend, the quality of the services through a full product life cycle, together with the cost of services, are key factors in making the competitive advantage in new markets. In most cases in today's business, there is always the Service Level Agreement (SLA) that has to be maintained as well. Therefore, there is a clear need for taking into consideration the complexity of the programmed solution, that is the basis of the given service, probability of an error occurrence, and all costs that will be associated with operating the service. In this paper, the important elements of the quality of the software that is considered a service to a business function are analyzed. The proposal of the six step method, which could be utilized in continuous quality improvements, is given. With this method, it is possible to better understand the root reasons for a specific service's behavior. Understanding service behavior is the key prerequisite for service improvement. The method encapsulates systematic approach in comparative analysis of the defined parameters of each service, with the same parameters of other services that belong to the same rank. These relative comparisons are proposed to be done in drill-in cycles until getting to the point of clear understanding of what makes one service better than the other and vice versa, in the given business environments. Each single conclusion on each level of cycled comparative measurements would trigger improvement action at that level. This method also provides the management with better tools to perform adequate human resources capacity planning for each software service for the given time frame. An example of the method utilization on one selected use case is given as well.

Ontology technologies have been widely studied for their capabilities of semantic description and knowledge inference in a variety of application domains. The main obstacle for the advancement of ontologies is the immature building methods and construction principles. It is challenging to discover how to tune a large complete ontology to small applications and build domain ontologies pragmatically. This paper proposes a hierarchical tree method that provides guidelines to the building of a hierarchical geo-ontology and corresponding construction rules for different levels of ontologies. This hierarchical ontology construction method can be used to realize lower-level ontology building based on the restrictions of the upper-level ontology. It can also connect different levels of ontologies into a hierarchical structure. Based on the resulting hierarchical tree structure, the management and usage of ontologies becomes feasible and more efficient. Furthermore, to better elaborate the hierarchical relationships among the concepts surrounding the basic tree structure, this paper introduces Class Meta-Information (CMI) to OWL (Ontology Web Language) and uses Hierarchical Identification (HID) to draw conclusion on concepts' hierarchical relations. Examples, experimental simulation and comparative analyses are given to explain further the applications of this hierarchical tree method in the areas of ontology engineering.