Vesna Jevtic

Identifying properties of software change request process: Qualitative investigation in very small software companies

Software systems change during all phases of their life cycles. After software delivery, users should have effective ways for specifying new requests and reporting problems. Handling of this new requests or problem reports must be supported with sound processes and appropriate tools. In this paper is presented a segment of qualitative research conducted with software experts from very small software companies related to change request process in maintenance phase of software life cycle. Software experts were interviewed in their companies or participated in focus groups. This research used constructivist grounded theory that is suitable methodology for creating explanations of common practice. Analysis of qualitative empirical data revealed properties regarding process implementation, the level of automation, feedback, iterativeness and process duration.

A comparison of rule sets induced by techniques based on rough set theory

The main goal of this paper is to investigate the performance of rule sets obtained by different techniques based on the rough set theory. The performance of a rule set is defined as its ability to classify a set of objects into predefined classes. The set of rules contains the if then form rules. The set of objects is represented by flat table (table, organized data) where each object is represented by its attributes. To generate the rule sets we have used Rosetta software system. The performance of rule sets is measured by employment of the confusion matrix.

THE DISTRIBUTION OF TIME FOR CLARK'S FLOW AND RISK ASSESSMENT FOR THE ACTIVITIES OF PERT NETWORK STRUCTURE

This paper presents the ways of quantification of flow time qualifications that can be used for planning or other stochastic processes by employing Clarks methods, central limit theorem and Monte Carlo simulation. The results of theoretical researches on superponed flow time quantification for complex activities and events flow in PERT network for project management are also presented. By extending Clarks research we have made a generalization of flow models for parallel and ordinal activities and events and specifically for their critical and subcritical paths. This can prevent planning errors and decrease the project realization risk. The software solution is based on Clarks equations and Monte Carlo simulation. The numerical experiment is conducted using Mathcad Professional.

Usability of virtual network laboratory in engineering education and computer network course

The importance of educational process in the field of Computer Science and Information Technology industry, as well as the need for educating highly skilled computer network professionals implies the importance of its course syllabus and laboratory tools. This paper presents evaluation and analysis of virtual network laboratory based on virtualization technology. The virtual network laboratory architecture is shown together with the supporting laboratory exercises. Evaluation criteria for these laboratory exercises include: description of learning goals, adopted skills, compatibility with course syllabus and side knowledge, and additional skills. Lessons learned after the virtual network laboratory course, are gathered as well. Detailed analysis of the skills and knowledge that students adopted in this environment is summarized. Also, overall usability estimation in education of various engineering profiles and related computer networking and communication courses is shown.

Context dependent maintenance effort estimation: Case study in a small software company

This paper presents an approach to software maintenance effort estimation based on the analysis of software maintenance requests available in issue tracking system in a very small local software company. Over 1900 requests, collected during 19 months in 2010 and 2011, were selected for analysis. The approach takes into account: the frequency of submitted user requests for particular periods of time important for organizing work in the company, the existence of maintenance service agreement for clients, the number of programmers assigned to the task associated to each request, and the number of working hours required for requests solving. The approach calculates correlation and establishes linear regression between frequencies of submitted user requests and the average time required for completing requests. This approach estimates an average number of working hours for processing user requests in periods of time that are important for internal company organization. In the paper are also discussed implications for practice and research, and provided recommendations for adapting this approach to other small software companies.

Application of modified shortest path algorithm for project duration assessment

As one of the triple constraint of project management, project completion time is very important issue. This is considerable for wide range of projects, especially for the time-terminated ones. Beside standard network planning methods, such as CPM, PERT, PDM etc. there are variety of alternative methods, based on previous ones, which are used in order to obtain even better project duration evaluations. In these methods researchers includes simulation, fuzzy theory, genetic algorithms etc. This paper describes the approach in modification of shortest path search algorithms and their usage in project duration assessment. Presented modification of shortest path algorithms is focused on its conversion to finding longest path in the network diagram i.e. to finding critical path of the project.

The design guidelines for virtual network laboratories

In the age of rapid development of communication technologies the educational process in the area of communication networks has the enormous significance. In this process the large number of skilled network professionals such as: software developers, system administrators, security engineers, etc., has to be trained. One of the most important elements of this process is existence of suitable educational environments. Nowadays the virtual network laboratories emerged as highly efficient environments for training network professionals. These environments are based on virtualization technology and provide working conditions in the emulated environments with the high level of reality. This paper deals with the important issues to be concerned in process of design and implementation of these laboratories. The structure of this laboratories and its configuration strongly depends on purpose and needs of the educational process itself, as well as of the current technology trends in the world. In this paper is presented the approach in defining the structure of virtual network laboratory and its design. This approach is based on research of current market trends, the dominant platforms and technologies used today, and on world trends in high education strategy and planning, especially in the area of networking and communication and related subjects as well. Analyzed data is used for design of the high efficiency virtual network laboratory able to provide the desired learning outcome. The architecture and structure of implemented laboratory is also described.

Shortest-path based model for warehouse inner transportation optimization

Nowadays economy demands elimination of any kind of wastes, and transportation is recognized as one of them. Efficient usage of routing algorithms can significantly reduce travelling distance and transportation costs as well. This paper describes usage of the shortest-path algorithm (in this case Dijkstras algorithm) for inner transportation optimization in warehouses. The model integrates data such as: 2D graph of warehouse layout, its 3D extension, historical data, ABC analysis and business process model. The prototype of proposed application is tested with sample data and by simulating different working conditions. Interpretation of obtained results is given too.

Using code instrumentation for creating initial impact set for software change request

Change impact analysis is the challenging area for research because of its complexity and the fact that studying software change requests consumes the largest amount of time during software maintenance. This paper addresses the problem of creating initial impact set that will provide the basis for change impact analysis. The approach can be applied on software business applications that intensively use databases and have graphical user interface that reflects database structure. The approach to code instrumentation that enables tracking a user session on the visual forms level, and a model of initial impact set that is created based on the session trace and software architecture are presented in the paper. Real setting implementation provides the evidence that this approach could be used in the practice.

Project Duration Assessment Model Based on Modified Shortest Path Algorithm and Superposition

This paper presents project duration assessment model based on modification of shortest path algorithms and superposition. One of the shortest path algorithms, Dijkstra algorithm, is modified in order to find the longest path. This is used for critical path calculation, i.e. for resolving project duration assessment problem. Another modification of algorithm calculates sub critical path as the second longest one. These paths are used for superposition, because of stochastic nature of many research and development projects which can cause that at some point in time sub critical becomes critical path. Thus, sub critical path influence on project duration should be taken into account, and, in this case, superposition is used for that. Superposition used in the model is based on analytical method -- Clarks formulas. Presented model can be used for business process improvement and project management support.