Software product lines (SPLs) manage product variants in a systematical way and allow stakeholders to derive variants by selecting features. Finding a desirable variant is hard, due to the huge configuration space and usually conflicting objectives (e.g., lower cost and higher performance). This scenario can be reduced to a multi-objective optimization prob- lem in SPLs. We address the problem using an exact and an approximate algorithm and compare their accuracy, time consumption, scalability and parameter setting requirements on five case studies with increasing complexity. Our empirical results show that (1) it is feasible to use exact techniques for small SPL multi-objective optimization problems, and (2) approximate methods can be used for large problems but require substantial effort to find the best parameter settings for acceptable approximation. Finally, we discuss the tradeoff between accuracy and time consumption when using exact and approximate techniques for SPL multi-objective optimization and guide stakeholders to choose one or the other in practice.

First Person Shooter (FPS) games are one of the most popular game genres and have a history of over 2 decades. While there has been extensive research on such games, the focus has been limited to their analysis at an individual level. In this thesis, we present a comparative analysis of three first person shooter games - Doom, Quake3 and Cube from an architectural point of view. All of these games have come at different times in the history of first person shooter games, and thus possess different and unique features. We describe the process followed in deriving their architecture at various levels of abstraction – the file level, the subsystem level, the library/non-library level and the individual subsystem level for a given part of code. We conclude with a comparative analysis of the similarities and differences in the structure and architecture of the three gaming systems. / Thesis (Master, Computing) -- Queen's University, 2014-01-13 15:26:25.387

Service-based software can be exploited by potentially untrustworthy service requestors while providing services. Given that, it is important to identify, analyze the trust relationships between service providers and requestors, and incorporate them into the service-based software. Treating trust as a nonfunctional requirement (NFR) during software development and monitoring allows clarifying these relationships and measuring the trustworthiness of service requestors. This analysis is facilitated by incorporating trust scenarios and trust models into the software. A trust scenario describes a trust relationship between interested parties based on a specific context. A trust model provides trust equations to measure the trustworthiness of service requestors based on the analysis of service-based interactions. Although much research has been devoted to monitor service quality, to date, no approach has been proposed to develop and automatically monitor service providing software from trust perspectives. In this thesis, we propose a trust-aware service-based software development framework which utilizes our proposed Unified Modeling Language (UML) extension called UMLtrust (UML for trust scenarios)to specify the trust scenarios of a service provider and incorporates our developed trust model called CAT (Context-Aware Trust) into the software to calculate the trustworthiness of service requestors. The trust scenarios are converted to trust rules to monitor service-based interactions. A service requestor is penalized for the violation of a trust rule and rewarded when no rule is violated. The trustworthiness of the requestor is then calculated (using the equations of CAT) based on the current request, outcomes of previous requests, and recommendations from other service providers. A trust-based service granting algorithm is presented to decide whether a service requestor should be granted the requested service. A trust monitoring architecture is presented which is assumed to reside in each service provider. The monitor uses trust rules from UMLtrust specifications and trust equations from CAT to analyze service-based interactions. The incorporation of the monitor into a provider makes it trust-aware. A trust monitoring algorithm is provided to analyze interactions and make decisions at run-time. A prototype of a file sharing service-based grid is implemented to evaluate the applicability of our framework that confirms the effectiveness of the framework. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2008-02-11 15:57:22.003 / Natural Sciences and Engineering Research Council (NSERC)

Software clones are considered harmful in software maintenance and evolution. However, despite a decade of active research, there is a marked lack of work in the detection and analysis of near-miss software clones, those where minor to extensive modifications have been made to the copied fragments. In this thesis, we advance the state-of-the-art in clone detection and analysis in several ways. First, we develop a hybrid clone detection method, called NICAD, that can detect both exact and near-miss clones with high precision and recall and with reasonable performance. Second, in order to address the decade of vagueness in clone definition, we propose an editing taxonomy for clone creation that models developers' editing activities in the copy/pasted code in a top-down fashion. NICAD is designed to address the different types of clones in the editing taxonomy. Third, we have conducted a scenario-based qualitative comparison and evaluation of all of the currently available clone detection techniques and tools in the context of a unified conceptual framework. Using the results of this study one can more easily choose the right tools to meet the requirements and constraints of any particular application, and can identify opportunities for hybridizing different techniques. The hybrid architecture of NICAD was derived from this study. Fourth, in order to evaluate and compare the available tools in a realistic setting and to avoid the challenges and huge manual effort in validating candidate clones, we have developed a mutation-based framework that automatically and efficiently measures (and compares) the recall and precision of clone detection tools for different fine-grained clone types of the proposed editing taxonomy. We have evaluated NICAD using this framework and found that it is capable of detecting different types of clones with high precision and recall. Finally, we have conducted a large scale empirical study of cloning in open source systems, both to evaluate NICAD and to study the cloning characteristics of these systems in several different dimensions. The study has demonstrated that NICAD is capable of accurately finding both exact and near-miss function clones even in large systems and different languages, and that there seem to be a large number of clones in those systems. / Thesis (Ph.D, Computing) -- Queen's University, 2009-08-31 14:05:30.233

Software clones are considered harmful in software maintenance and evolution. However, despite a decade of active research, there is a marked lack of work in the detection and analysis of near-miss software clones, those where minor to extensive modifications have been made to the copied fragments. In this thesis, we advance the state-of-the-art in clone detection and analysis in several ways. First, we develop a hybrid clone detection method, called NICAD, that can detect both exact and near-miss clones with high precision and recall and with reasonable performance. Second, in order to address the decade of vagueness in clone definition, we propose an editing taxonomy for clone creation that models developers' editing activities in the copy/pasted code in a top-down fashion. NICAD is designed to address the different types of clones in the editing taxonomy. Third, we have conducted a scenario-based qualitative comparison and evaluation of all of the currently available clone detection techniques and tools in the context of a unified conceptual framework. Using the results of this study one can more easily choose the right tools to meet the requirements and constraints of any particular application, and can identify opportunities for hybridizing different techniques. The hybrid architecture of NICAD was derived from this study. Fourth, in order to evaluate and compare the available tools in a realistic setting and to avoid the challenges and huge manual effort in validating candidate clones, we have developed a mutation-based framework that automatically and efficiently measures (and compares) the recall and precision of clone detection tools for different fine-grained clone types of the proposed editing taxonomy. We have evaluated NICAD using this framework and found that it is capable of detecting different types of clones with high precision and recall. Finally, we have conducted a large scale empirical study of cloning in open source systems, both to evaluate NICAD and to study the cloning characteristics of these systems in several different dimensions. The study has demonstrated that NICAD is capable of accurately finding both exact and near-miss function clones even in large systems and different languages, and that there seem to be a large number of clones in those systems. / Thesis (Ph.D, Computing) -- Queen's University, 2009-08-31 14:05:30.233

This thesis investigates the following research questions: (1) What is open source project governance and how can it be conceptualized? (2) What is the relationship between the dimensions of OSS governance and the specific purposes that governance is hypothesized to serve in open source projects? (3) How do the major configurations of governance dimensions affect the performance of open source projects? Two studies were conducted to answer these questions: an exploratory qualitative study and a survey study. In the qualitative study, we clearly defined, developed, and validated the various dimensions of OSS governance. This allowed for the identification of a limited number of configurations of governance dimensions that most frequently occur in open source projects. We found that a patterning in governance dimensions takes place because dimensions are in fact interdependent. Therefore, only a fraction of the theoretically conceivable configurations of governance dimensions appear to be viable and were observed among a range of open source projects. This provided us with a preliminary understanding of how these dimensions configure to create three distinct configurations of project governance which were labeled as follows: Open Communities, Managed Communities, and Defined Communities. In the quantitative survey, we first validated these configurations of governance using cluster analysis and then tested the relationships between these configurations (clusters) and the specific purposes that governance is hypothesized to serve in open source projects, namely solve collective action dilemmas, solve coordination problems, and create a climate for project excellence, while assessing their influence on the performance of projects. The results confirmed the presence of three main governance configurations (clusters) and also showed that open source projects that adopt a Defined Community approach to governance were the most successful. In these types of projects, the combination of a tightly managed software development process with a decentralized community management structure was found to create a balance between anarchy and control that allows these projects to benefit from one of the virtues of open source development, the open contribution and participation of a wide variety of talented developers, while avoiding the pitfalls of an uncontrolled and scattered development process. / Thesis (Ph.D, Management) -- Queen's University, 2012-04-11 16:00:02.186

Taking attendance in classes having large numbers of students is a time consuming task. Most teachers would rather not do so in order to increase instruction time. An alternative way for taking attendance is developed in this project.This thesis describes a Four-Station-Microcomputer-Based Student Logger (FSAL) device designed and constructed for solving this problem. With this portable device, four students can input their identification codes at the same time. Approximately ten seconds per student is needed to register their attendance. In this manner, a class of one-hundred students could indicate their attendance in less than five minutes.Presented herein is the background information about the microcomputer, the hardware design and the software developed for the FSAL device. This device is located in Department of Physics and Astronomy and is planned to be used in the courses ASTRO 100 and PHYCS 100. / Department of Physics and Astronomy

The Software Engineering Research Center (SERC) Design Metrics Research Team at Ball State University has developed a design metric D(G) of the form:D(G) = D~ + DiWhere De is the architectural design metric (external design metric) and D; is the detailed design metric (internal design metric).Questions to be investigated in this thesis are:Why can D, be an indicator of the potential error modules?Why can D; be an indicator of the potential error modules?Are there any significant factors that dominate the design metrics?In this thesis, the report of the STANFINS data is evaluated by using correlation analysis, regression analysis, and several other statistical techiques. The STANFINS study is chosen because it contains approximately 532 programs, 3,000 packages and 2,500,000 lines of Ada.The design metrics study was completed on 21 programs (approximately 24,000 lines of code) which were selected by CSC development teams. Error reports were also provided by CSC personnel. / Department of Computer Science

Software engineers currently rely on lengthy source code reviews, testing, and static analysis tools to attempt identification of software vulnerabilities. While these are sometimes effective, the methods used are limited and don't catch all security vulnerabilities.Work has been done in identifying areas of software prone to failure through a design metrics approach, and with success. This study aims to extend this idea to software security. The premise of this thesis is that the set of security vulnerabilities overlaps (or may be a subset of) the overall set of software bugs and failures. It is postulated that a good, reliable design should also be a secure design. This thesis identifies design issues which may lead to security vulnerabilities and proposes possible design metric enhancements to capture these design properties. / Department of Computer Science

The development of a software package is a complex and time consuming process. Computer Assisted Software Engineering (CASE) tools, such as Excelerator, DesignAid and SA Tools have offered an alternative to the traditional methods of system design. While the use of these design tools can lessen the burden of project management, there currently exists no systematic method for describing or evaluating existing products.This study identifies criteria for software development tools by examining three products used in a PC-based computing environment. The three software development tools studied are DesignAid version 4.0 by Nastec Corporation, SA Tools by Tekcase Corporation, and Excelerator version 1.7 by Index Technology Corporation. In order to give the "look and feel" of the products, the same design project is implemented on each of the tools. Then each product is evaluated with respect to a given set of criteria. / Department of Computer Science