With the increasing availability of storage and computing power, Latent Semantic Analysis (LSA) has gained more and more significance in practice over the last decade. This diploma thesis aims to develop a reference architecture which can be utilised to provide LSA based applications in a distributed system. It outlines the underlying problems of generation, processing and storage of large data objects resulting from LSA operations, the problems arising from bringing LSA into a distributed context, suggests an architecture for the software components necessary to perform the tasks, and evaluates the applicability to real world scenarios, including the implementation of a classroom scenario as a proof-of-concept. (author's abstract) / Series: Theses / Institute for Statistics and Mathematics

With recognition of turnover as a financial issue increasing, companies are searching for strategies to confront the problem in ways that generate a good return on investment. Successfully managing turnover is a matter of understanding its costs, causes and cures. In service–oriented industries such as banking, people are considered among the most important assets of a firm. Forward–thinking banks are looking for ways to leverage people, along with processes and technology, to achieve their objectives. Employee expectations are changing, too, forcing organisations to place a greater emphasis on talent management strategies and practices. Employees rarely quit on the spot. Generally, an employee becomes dissatisfied and stays disengaged for quite a while before leaving. However, from the moment of disengagement, most employees are no longer as dedicated or productive as they once were. Nearly all the real reasons why employees quit, fall into four basic categories of human needs: the need for trust, the need for hope, the need to feel competent, and the need to feel valued and trustworthy (Branham, 2005). Thirteen possible reasons for resignations were identified within the banking sector, namely: desire to take on a new challenge, bad relationship with management, bad relationship with colleagues, lack of opportunity for advancement, lack of appreciation (perception of recognition), better compensation and benefits elsewhere, long working hours, lack of control over work or working environment, travelling distance to work, personal satiation at home, lack of training and support to reach potential, the department is conducive to black advancement, the bank embraces diversity for all. Most of the employees that resigned voluntary did so because of lack of opportunity for advancement, a desire to take on a new challenge and a lack of appreciation. The statistical analysis revealed that amongst position title, there is a statistical significance for the bank embraces diversity for all as a reason for resignation and that the effect between junior managers and team leaders has a large effect. Analysis by gender differences shows that there is a statistical significance for personal situation at home as a reason for resignation and that females feels stronger about this than males. When looked at the difference between ethnic group, there are two reasons that are statistical significant namely, better compensation elsewhere and long working hours. Africans, coloureds and white‘s size effect is large, meaning that Africans and coloureds feel stronger about leaving for better compensation elseware than whites. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.

Researchers in software engineering proposed design method for distributed applications to construct a set of communicating system components from a global behavior. The joint behaviors of these components must precisely satisfy the specified global behavior. The next concern is to transform the constructed models of these components into executable business processes by ensuring the exchange of asynchronous messages among the generated business processes. The introduction of Service-Oriented Architecture (SOA) has helped to achieve this goal. SOA provides high flexibility in composing loosely-integrated services that can be used among business domains to carry out business transactions; this composition is known as service orchestration. Moreover, SOA supports Model Driven Architecture (MDA) such that services modeled as UML Activity Diagrams (AD) can be transformed into a set of Business Execution Language (BPEL) processes. Many researchers discussed the transformation of UML AD and the Business Process Modeling Notation (BPMN) into BPEL. However, they did not discuss the practical limitations that some of these transformations impose. This thesis addresses the imitations of the transformation from UML AD to BPEL processes using the IBM Rational Software Architect (RSA). We showed here that the tool is unable to create the correct BPEL artifacts from UML AD components in certain cases, for instance when the behavior includes the alternative for receiving single or concurrent messages, a weak loop, or certain choice activities. Furthermore, we provided novel solutions to the transformations in these cases in order to facilitate the transformation from UML AD to BPEL.

Virtual Organizations (VO)—a network of independent organizations collaborating to address specific business opportunities—have become popular in today’s technology driven business environment. Due to their autonomous and interdependent nature, management of collaboration among such organizations is a challenging task. Although many solutions have been proposed over the past two decades to support inter-organizational interactions, VOs still face several challenges due to their dynamic and temporal nature that cannot be addressed by traditional solutions such as ebXML, RosettaNet and EDI. In this research, we present a framework for process management in service oriented virtual organizations and a distributed architecture for a flexible infrastructure that supports collaborative business process execution, monitoring and management. The framework contains 6 layers with multiple components within each layer. In designing the components of the framework, standard reference architecture such as the Open-EDI reference model and the S3 service oriented architecture, as well as best practices such as ITIL V3 and PMBOK are used. The infrastructure supports the common topologies of inter-organizational collaboration (e.g. peer-to-peer, star, linear), and responds well to changes due to its loosely coupled components. The proposed infrastructure is based on federating multiple SOA infrastructures with the Enterprise Service Bus (ESB) as its core. It is implemented using IBM WebSphere ™ products. We demonstrate that VOs built with our framework and implementation architecture facilitate flexibility, rapid process integration and dynamic evolution.

Management of Virtual Organizations faces new challenges that traditional approaches cannot address. This research proposes a performance measurement framework for service oriented virtual organizations including a structural and a procedural component. The structural framework aligns the activities of partners in a virtual organization at three different layers. The first layer is designed for partners’ strategic alignment through coordination of the value creation network. In the second layer, performance dimensions of partners’ collaboration are defined and mapped to the service choreography model. The third layer focuses on assessing effectiveness and efficiency of partners’ domain specific services, which is designed based on ITIL V3 service level management guidelines. In order to consolidate the structural framework, these three layers are integrated using a method for extracting service choreography model and SLA aggregation patterns from the value network. The procedural framework, on the other side, defines the processes required to design the KPI structure, implement the solution, communicate the results, and derive improvements. We propose an implementation architecture that enables inter-organizational performance management in collaborative environments. Then, the IBM products for business process and performance management (IBM BPM, Business Monitor, and Cognos BI) are employed to implement the proposed architecture. The conceptual framework along with the implementation architecture provides an integrated solution for decentralized performance measurement without the need for a central authority. We demonstrate that the proposed solution enhances flexibility, scalability, and interoperability, and supports transparency of partners’ performance information at an agreed-upon level as a basis for mutual trust.

Service Oriented Virtual Organizations (SOVOs) business processes and services are subject to change to meet the internal and external requirements of the competitive, complex and rapidly changing environment they operate in. More practical and efficient ways of change management are needed to allow different partners to initiate changes to their business process and services in a faster and user-transparent manner. This thesis proposes a Change Management Framework for service oriented virtual organizations including a structural and a procedural framework. The structural framework categorizes changes in the SOVO into three layers of change; which include the value network layer, the collaborative process layer and the service providers’ layer, and identifies the impact of change on each layer. Furthermore, the structural framework identifies various triggers of changes which eventually lead to actions taken at the three layers. The change management procedural framework is derived from the ITIL V3, ECM and ECOLEAD best practices and recommendations, customized to fit the SOVO change requirements. It provides different components including the six layers for change processes, change control, change actors and related management processes. The change management procedural framework provides a sequence of steps and methods that the SOVO and its participated organizations can follow in initiating changes to their business processes or services. We design an implementation architecture and a prototype for building the change management console which enables the SOVO change management participants to initiate, assess, collaborate, monitor and authorize changes. The prototype is developed to realize and validate the change management process of change in the SOVO environment. We employ the various capabilities of the IBM Business Process Management (BPM) (including its recent Web 2.0 capabilities) to increase the collaboration between partners in the process of change. We demonstrate that the proposed solutions facilitate and enhance the process of change by effectively engaging the SOVO partners in the process of change.

With recognition of turnover as a financial issue increasing, companies are searching for strategies to confront the problem in ways that generate a good return on investment. Successfully managing turnover is a matter of understanding its costs, causes and cures. In service–oriented industries such as banking, people are considered among the most important assets of a firm. Forward–thinking banks are looking for ways to leverage people, along with processes and technology, to achieve their objectives. Employee expectations are changing, too, forcing organisations to place a greater emphasis on talent management strategies and practices. Employees rarely quit on the spot. Generally, an employee becomes dissatisfied and stays disengaged for quite a while before leaving. However, from the moment of disengagement, most employees are no longer as dedicated or productive as they once were. Nearly all the real reasons why employees quit, fall into four basic categories of human needs: the need for trust, the need for hope, the need to feel competent, and the need to feel valued and trustworthy (Branham, 2005). Thirteen possible reasons for resignations were identified within the banking sector, namely: desire to take on a new challenge, bad relationship with management, bad relationship with colleagues, lack of opportunity for advancement, lack of appreciation (perception of recognition), better compensation and benefits elsewhere, long working hours, lack of control over work or working environment, travelling distance to work, personal satiation at home, lack of training and support to reach potential, the department is conducive to black advancement, the bank embraces diversity for all. Most of the employees that resigned voluntary did so because of lack of opportunity for advancement, a desire to take on a new challenge and a lack of appreciation. The statistical analysis revealed that amongst position title, there is a statistical significance for the bank embraces diversity for all as a reason for resignation and that the effect between junior managers and team leaders has a large effect. Analysis by gender differences shows that there is a statistical significance for personal situation at home as a reason for resignation and that females feels stronger about this than males. When looked at the difference between ethnic group, there are two reasons that are statistical significant namely, better compensation elsewhere and long working hours. Africans, coloureds and white‘s size effect is large, meaning that Africans and coloureds feel stronger about leaving for better compensation elseware than whites. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.

Due to the dramatic increase in intrusion activities, the definition and evaluation of software security requirements have become important aspects of the development of software services. It is now a well-accepted fact in software engineering that security concerns, like any other quality concerns, should be dealt with in the early stages of software development process. Current practices for software security architecture risk analysis, however, still heavily rely on human expertise. This involves a significant amount of subjective efforts creating a greater potential for inaccuracies. In this dissertation, we propose a framework for quantitative security architecture analysis for service-oriented software systems. In this regard two important contributions are made in the dissertation. First, we identify and define some internal security attributes and related properties based on a generic service-oriented software model, setting up a framework for the definition and formal evaluation of corresponding security metrics. Second, we propose a measurement abstraction paradigm named User System Interaction Effect (USIE) model that can be used to systematically derive and analyze security concerns from service-oriented software architectures. Many aspects of the model derivation and analysis can be automated, which limit the amount of user involvement and, thereby, reduce the subjectivity underlying typical security analysis process. The model can be used as a foundation for quantitative analysis of software services from different security perspectives with respect to the internal security properties introduced. Based on sample metrics derived from the framework, we illustrate empirically the viability of our paradigm by conducting case studies based on existing open source software.

During the past decade service-orientation has become a popular design paradigm, offering an approach in which services are the functional building blocks. Services are self-contained units of composition, built to be invoked, composed, and destroyed on (user) demand. Service-oriented systems (SOS) are a collection of services that are developed based on several design principles such as: (i) loose coupling between services (e.g., inter-service communication can involve either simple data passing or two or more connected services coordinating some activity) that allows services to be independent, yet highly interoperable when required; (ii) service abstraction, which emphasizes the need to hide as many implementation details as possible, yet still exposing functional and extra-functional capabilities that can be offered to service users; (iii) service reusability provided by the existing services in a rapid and flexible development process; (iv) service composability as one of the main assets of SOS that provide a design platform for services to be composed and decomposed, etc. One of the main concerns in such systems is ensuring service quality per se, but also guaranteeing the quality of newly composed services. To accomplish the above, we consider two system perspectives: the developer's and the user's view, respectively. In the former, one can be assumed to have access to the internal service representation: functionality, enabled actions, resource usage, and interactions with other services. In the second, one has information primarily on the service interface and exposed capabilities (attributes/features). Means of checking that services and service compositions meet the expected requirements, the so-called correctness issue, can enable optimization and possibility to guarantee a satisfactory level of a service composition quality. In order to accomplish exhaustive correctness checks of design-time SOS, we employ model-checking as the main formal verification technique, which eventually provides necessary information about quality-of-service (QoS), already at early stages of system development. ~As opposed to the traditional approach of software system construction, in SOS the same service may be offered at various prices, QoS, and other conditions, depending on the user needs. In such a setting, the interaction between involved parties requires the negotiation of what is possible at request time, aiming at meeting needs on demand. The service negotiation process often proceeds with timing, price, and resource constraints, under which users and providers exchange information on their respective goals, until reaching a consensus. Hence, a mathematically driven technique to analyze a priori various ways to achieve such goals is beneficial for understanding what and how can particular goals be achieved. This thesis presents the research that we have been carrying out over the past few years, which resulted in developing methods and tools for the specification, modeling, and formal analysis of services and service compositions in SOS. The contributions of the thesis consist of: (i)constructs for the formal description of services and service compositions using the resource-aware timed behavioral language called REMES; (ii) deductive and algorithmic approaches for checking correctness of services and service compositions;(iii) a model of service negotiation that includes different negotiation strategies, formally analyzed against timing and resource constraints; (iv) a tool-chain (REMES SOS IDE) that provides an editor and verification support (by integration with the UPPAAL model-checker) to REMES-based service-oriented designs;(v) a relevant case-study by which we exercise the applicability of our framework.The presented work has also been applied on other smaller examples presented in the published papers. / Under det senaste årtiondet har ett tjänstorienterat paradigm blivit allt-mer populärt i utvecklingen av datorsystem. I detta paradigm utgör så kallade tjänster den minsta funktionella systemenheten. Dessa tjänster är konstruerade så att de kan skapas, användas, sammansättas och avslutas separat. De ska vara oberoende av varandra samtidigt som de ska kunna fungera effektivt tillsammans och i samarbete med andra system när så behövs. Vidare ska tjänsterna dölja sina interna implementa-tionsdetaljer i så stor grad som möjligt, samtidigt som deras fulla funktionalitet ska exponeras för systemdesignern. Tjänsterna ska också på ett enkelt sätt kunna återanvändas och sammansättas i en snabb och flexibel utvecklingsprocess.En av de viktigaste aspekterna i tjänsteorienterade datorsystem är att kunna säkerställa systemens kvalitet. För att åstadkomma detta ärdet viktigt att få en djupare insikt om tjänstens interna funktionalitet, i termer av möjliga operationer, resursinformation, samt tänkbar inter-aktion med andra tjänster. Detta är speciellt viktigt när utvecklaren har möjlighet att välja mellan två funktionellt likvärda tjänster somär olika med avseende på andra egenskaper, såsom responstid eller andra resurskrav. I detta sammanhang kan en matematisk beskrivning av en tjänsts beteende ge ökad förståelse av tjänstemodellen, samt hjälpa användaren att koppla ihop tjänster på ett korrekt sätt. En matematisk beskrivning öppnar också upp för ett sätt att matematiskt resonera kring tjänster. Metoder för att kontrollera att komponerade tjänstermöter ställda resurskrav möjliggör också resursoptimering av tjänster samt verifiering av ställda kvalitetskrav.I denna avhandling presenteras forskning som har bedrivits under de senaste åren. Forskningen har resulterat i metoder och verktyg föratt specificera, modellera och formellt analysera tjänster och sammansättning av tjänster. Arbetet i avhandlingen består av (i) en formell definition av tjänster och sammansättning av tjänster med hjälp avett resursmedvetet formellt specifikationsspråk kallat Remes; (ii) två metoder för att analysera tjänster och kontrollera korrektheten i sammansättning av tjänster, både deduktivt och algoritmiskt; (iii) en modell av förhandlingsprocessen vid sammansättning av tjänster som inkluderar olika förhandlingsstrategier; (iv) ett antal verktyg som stödjer dessa metoder. Metoderna har använts i ett antal fallstudier som är presenterade i de publicerade artiklarna. / Contesse

Web services are increasingly gaining acceptance as a framework for facilitating application-to-application interactions within and across enterprises. It is commonly accepted that a service description should include not only the interface, but also the business protocol supported by the service. The present work focuses on the formalization of the important category of protocols that include time-related constraints (called timed protocols), and the impact of time on compatibility and replaceability analysis. We formalized the following timing constraints: CInvoke constraints define time windows of availability while MInvoke constraints define expirations deadlines. We extended techniques for compatibility and replaceability analysis between timed protocols by using a semantic-preserving mapping between timed protocols and timed automata, leading to the novel class of protocol timed automata (PTA). Specifically, PTA exhibit silent transitions that cannot be removed in general, yet they are closed under complementation, making every type of compatibility or replaceability analysis decidable. Finally, we implemented our approach in the context of a larger project called ServiceMosaic, a model-driven framework for web service life-cycle management.