21 research outputs found
Sustaining the quality of Web services
No full textWithin the framework of Service Oriented Architecture, we introduce a new framework in order to better sustain the quality of Web services. The framework groups similar Web services together. Our contributions include mechanisms on both the micro-management and macro-management of a group of Web services in order to better sustain the quality of Web services. Finally we demonstrate the effectiveness of the mechanisms through experiments using some real-world values.(DOCSC06) -- FUNDP, 201
Towards Defining and Assessing the Non-Functional Properties of Communities of Web Services
No full textThis paper discusses some of the research done in the area of communities of Web services. A community allows Web services offering similar functionalities to be grouped together. One challenge that arises as a result of this grouping concerns the assessment of the level of service of the community. We refer to this level of service as Quality of Community (QoC). The QoC is important as it permits differentiating the communities from each other as well as promoting and maintaining a certain service level in preparation for receiving user requests for processing. The QoC of a community is assessed based on the QoSs of the individual Web services that reside in this community. Different attributes specific to the community such as variance, selection rate, and substitution rate define the QoC. Experiments illustrating the use of the QoC are, also, reported in this paper. © 2011 IEEE
Using fixed-price auctions for selection in communities of web services
No full textThis paper introduces an approach that allows Web services to handle user requests where the price that the users are willing to pay is fixed. In such cases, a user search for the highest quality of service based on the submitted fixed price. Instead of searching for individualWeb services, the user finds it more convenient to send requests to middlemen (or brokers) who act on behalf of a group of Web services. These middlemen then select a Web service within the group to handle the request. In this paper we demonstrate how fixed price requests can be included into the operation of a community of Web services. Our approach introduces auction theory into the selection process. Experiments using real world values are conducted to demonstrate the effectiveness of the approach.</p
Communication of technical QoS among cloud brokers
No full textService brokers are commonly used in the cloud computing paradigm to represent service requesters to select a service provider. They act as an intermediary between the two parties. One model of the cloud computing paradigm involves 3 layers, the user, the SaaS provider and the Cloud provider. The selection of service requesters is challenging due to the different levels of Quality of Service that each service provider can provide. In this paper we propose a unique mechanism that allows communication between service brokers in different layers in order to further improve this selection. In addition, we introduce a metric, efficiency, which service brokers can use to deterministically compare service providers with each other.</p
Social Engineering of Communities of Web Services
No full textThis paper discusses the engineering of communities of Web services with emphasis on the social interactions that arise between these Web services and hence, can put some restrictions on their behaviors. Like service parks, communities gather Web services that offer similar functionalities to users. The social interactions between Web services take place within and across communities and are captured using structures known as social networks. Five types of networks are established during this engineering, which are supervision, competition, substitution, collaboration, and recommendation. Above these networks mining operations are performed, which results in assigning social attributes to Web services such as selfishness, fairness, and unpredictability. Details on the experiments are, also, reported in this paper. © 2011 IEEE
Using 3-Way Satisfaction for Web Service Selection - preliminary investigations
No full textThis paper examines the problem of Web service selection in a community. Web services reside in communities due to the similiar functionalities they offer. The selection in communities is important because each Web service provides a different level of service. Selection methods thus far only consider the satisfaction of users and neglect the satisfaction of Web services and the community to which they belong. In this paper we propose a method of selecting a Web service based on the satisfaction of all three parties - user, Web service and community. The proposed solution consists of first formalizing the selection process and then using linear programming techniques to define a score function, which can be maximized to find the best selection based on the three satisfaction factors. © 2011 IEEE
PEMM Model-Based Process Management Maturity Assessment in Elektrilevi OÜ
No full textMagistritöö Ökonoomika ja ettevõtluse õppekavalProtsessijuhtimine on levinud juhtimislähenemine, mis keskendub ettevõtte efektiivsele
juhtimisele protsesside kaudu, tagades sellega konkurentsieelis. Kuna protsessijuhtimine
hõlmab kogu organisatsiooni ja sõltub paljudest organisatsiooni teguritest, siis selle suure
ulatuse tõttu tekivad protsessijuhtimise rakendamisel erinevad probleemid. Käesolevas
magistritöös hinnatakse Elektrilevi OÜ protsessijuhtimise toimist ning saadud tulemuste
põhjal koostatakse parendusettepanekud. Hindamine viiakse läbi Dr. Michael Hammer
poolt välja töötatud PEMM mudeli alusel. Selleks küsitletakse juhtide hinnanguid ja
arvamusi ning analüüsitakse ettevõtte dokumente. Uuringu tulemused iseloomustavad
ettevõtte protsessijuhtimise toimimise taset ja on rakendatavad arengukava koostamisel,
pakkudes hinnatavale ettevõttele praktilist väärtust.Business Process Management is a widespread management approach, that focuses on the
effective management of a company through processes to ensure competitive advantage.
As the process management involves the whole organization and depends on several
organization’s characteristics, then due to its wide capacity, various problems arise in
enforcing process management. Within this Master’s Thesis, the author has analyzed
performance of process management within Elektrilevi OÜ and proposed improvements
based on the results. The evaluation is based on the PEMM model, authored by Dr.
Michael Hammer. The work is based on the managers’ evaluations and opinions, also on
enterprise’s documents. The results present the enterprise’s process management
performance level and can be applied in the creation of the development plan. The results
are of practical value to the evaluated enterprise
String field theory: a modern introduction
No full textThis textbook provides an introduction to string field theory (SFT). String theory is usually formulated in the worldsheet formalism, which describes a single string (first-quantization). While this approach is intuitive and could be pushed far due to the exceptional properties of two-dimensional theories, it becomes cumbersome for some questions or even fails at a more fundamental level. These motivations have led to the development of SFT, a description of string theory using the field theory formalism (second-quantization). As a field theory, SFT provides a rigorous and constructive formulation of string theory. The main focus of the book is the construction of the closed bosonic SFT. The accent is put on providing the reader with the foundations, conceptual understanding and intuition of what SFT is. After reading this book, the reader is able to study the applications from the literature. The book is organized in two parts. The first part reviews the notions of the worldsheet theory that are necessary to build SFT (worldsheet path integral, CFT and BRST quantization). The second part starts by introducing general concepts of SFT from the BRST quantization. Then, it introduces off-shell string amplitudes before providing a Feynman diagrams interpretation from which the building blocks of SFT are extracted. After constructing the closed SFT, the author outlines the proofs of several important properties such as background independence, unitarity and crossing symmetry. Finally, the generalization to the superstring is also discussed
On the Analysis of Satisfaction for Web Services Selection
No full textThis paper addresses the issue of selecting Web services residing in a community. Since these Web services have similar functionalities, this selection depends on their Quality of Service (QoS). Existing approaches only consider the satisfaction of users\u27 requirements and neglect the satisfaction of Web services\u27 requirements and the community to which they belong. This paper proposes an approach of selecting Web services based on the satisfaction of all three parties - user, Web service, and community. The approach consists of first, formalizing the selection process and then, using integer programming to define a score function, which can be maximized to find the best selection based on three satisfaction factors. Experiments using real Web services and measurements are conducted to demonstrate the influences of the approach. © 2012 IEEE
