Дисертації з теми "Web service providers Evaluation"

The usage of cloud computing in order to move away from local servers and infrastructure have grown enormously the last decade. The ability to quickly scale capacity of servers and their resources at once when needed is something that can both be a price saver for companies and help them deliver high end products that will function correctly at all times even under heavy load to their customers. To meet todays challenges, one of the strategic directions of Attentec, a software company located in Linköping, is to examine the world of cloud computing in order to deliver robust and scalable applications to their customers. This thesis investigates the usage of cloud services in order to deploy scalable applications which can adapt to usage peaks within minutes.

With the emergence of the Web and its pervasive intrusion on individuals, organizations, businesses etc., people now realize that they are living in a digital environment analogous to the ecological ecosystem. Consequently, no individual or organization can ignore the huge impact of the Web on social well-being, growth and prosperity, or the changes that it has brought about to the world economy, transforming it from a self-contained, isolated, and static environment to an open, connected, dynamic environment. Recently, the European Union initiated a research vision in relation to this ubiquitous digital environment, known as Digital (Business) Ecosystems. In the Digital Ecosystems environment, there exist ubiquitous and heterogeneous species, and ubiquitous, heterogeneous, context-dependent and dynamic services provided or requested by species. Nevertheless, existing commercial search engines lack sufficient semantic supports, which cannot be employed to disambiguate user queries and cannot provide trustworthy and reliable service retrieval. Furthermore, current semantic service retrieval research focuses on service retrieval in the Web service field, which cannot provide requested service retrieval functions that take into account the features of Digital Ecosystem services. Hence, in this thesis, we propose a customized semantic service retrieval methodology, enabling trustworthy and reliable service retrieval in the Digital Ecosystems environment, by considering the heterogeneous, context-dependent and dynamic nature of services and the heterogeneous and dynamic nature of service providers and service requesters in Digital Ecosystems.The customized semantic service retrieval methodology comprises: 1) a service information discovery, annotation and classification methodology; 2) a service retrieval methodology; 3) a service concept recommendation methodology; 4) a quality of service (QoS) evaluation and service ranking methodology; and 5) a service domain knowledge updating, and service-provider-based Service Description Entity (SDE) metadata publishing, maintenance and classification methodology.The service information discovery, annotation and classification methodology is designed for discovering ubiquitous service information from the Web, annotating the discovered service information with ontology mark-up languages, and classifying the annotated service information by means of specific service domain knowledge, taking into account the heterogeneous and context-dependent nature of Digital Ecosystem services and the heterogeneous nature of service providers. The methodology is realized by the prototype of a Semantic Crawler, the aim of which is to discover service advertisements and service provider profiles from webpages, and annotating the information with service domain ontologies.The service retrieval methodology enables service requesters to precisely retrieve the annotated service information, taking into account the heterogeneous nature of Digital Ecosystem service requesters. The methodology is presented by the prototype of a Service Search Engine. Since service requesters can be divided according to the group which has relevant knowledge with regard to their service requests, and the group which does not have relevant knowledge with regard to their service requests, we respectively provide two different service retrieval modules. The module for the first group enables service requesters to directly retrieve service information by querying its attributes. The module for the second group enables service requesters to interact with the search engine to denote their queries by means of service domain knowledge, and then retrieve service information based on the denoted queries.The service concept recommendation methodology concerns the issue of incomplete or incorrect queries. The methodology enables the search engine to recommend relevant concepts to service requesters, once they find that the service concepts eventually selected cannot be used to denote their service requests. We premise that there is some extent of overlap between the selected concepts and the concepts denoting service requests, as a result of the impact of service requesters’ understandings of service requests on the selected concepts by a series of human-computer interactions. Therefore, a semantic similarity model is designed that seeks semantically similar concepts based on selected concepts.The QoS evaluation and service ranking methodology is proposed to allow service requesters to evaluate the trustworthiness of a service advertisement and rank retrieved service advertisements based on their QoS values, taking into account the contextdependent nature of services in Digital Ecosystems. The core of this methodology is an extended CCCI (Correlation of Interaction, Correlation of Criterion, Clarity of Criterion, and Importance of Criterion) metrics, which allows a service requester to evaluate the performance of a service provider in a service transaction based on QoS evaluation criteria in a specific service domain. The evaluation result is then incorporated with the previous results to produce the eventual QoS value of the service advertisement in a service domain. Service requesters can rank service advertisements by considering their QoS values under each criterion in a service domain.The methodology for service domain knowledge updating, service-provider-based SDE metadata publishing, maintenance, and classification is initiated to allow: 1) knowledge users to update service domain ontologies employed in the service retrieval methodology, taking into account the dynamic nature of services in Digital Ecosystems; and 2) service providers to update their service profiles and manually annotate their published service advertisements by means of service domain knowledge, taking into account the dynamic nature of service providers in Digital Ecosystems. The methodology for service domain knowledge updating is realized by a voting system for any proposals for changes in service domain knowledge, and by assigning different weights to the votes of domain experts and normal users.In order to validate the customized semantic service retrieval methodology, we build a prototype – a Customized Semantic Service Search Engine. Based on the prototype, we test the mathematical algorithms involved in the methodology by a simulation approach and validate the proposed functions of the methodology by a functional testing approach.

This study examined the perspectives of agencies providing career development services in Canada concerning the current state of efficacy assessment. The central question guiding this research was: How do representatives of career services agencies perceive their evaluation practices and the results they are obtaining? A total of 147 (n=147) agency representatives participated in an on-line survey. The data obtained through the use of this survey were analyzed using a mixed methods design - methods included frequency analysis, Chi square analysis and qualitative methods (to conduct content analysis). A number of conclusions were drawn from this study. It appears that the vast majority of agencies value reporting on the outcomes of the services they provide and do engage in efficacy measurement. However, it is also apparent that certain types of career development agencies do not value and do not engage in efficacy measurement to the same extent as other types of career development agencies. In addition, it appears that a strong emphasis is currently being placed on tallying the number of clients who secure employment or return to school with a lack of emphasis being placed on other outcomes. Finally, according to the sample in this survey, agency representatives are encountering many obstacles in their attempts to measure the effectiveness of the services they provide. The results of this study have many implications for the field of career development. In order to provide a sound body of evidence attesting to the efficacy of career development services much work will have to be done to build a strong framework to ensure accountability.
xiv, 151 leaves ; 29 cm.

The need to address the issue of quality in aged care service provision in Australia has received increasing emphasis in recent decades. Particularly since the 1980s, the federal government has played a key role in ensuring that this is the case through the implementation of various reforms and regulatory strategies. In 1998, the national standards monitoring system which had been in place since the mid 1980s was replaced with a new system based on an accreditation model. In contrast to the former system which was wholly controlled by government and involved one-off inspections by government standards monitors, responsibility for managing the new system has been devolved to an independent body, the Aged Care Standards and Accreditation Agency. One of the Agency's primary functions is to assess compliance with the accreditation standards. A key component of the new system is its emphasis on continuous improvement which has been incorporated into the accreditation standards. As a consequence, the new system requires a much greater level of involvement and commitment by providers than previously. In order to continue receiving government funding all facilities had to be accredited by January 1st 2001. This study represents an evaluation of the accreditation system based on the views and experiences of service providers in Western Australia. It explored a number of issues relating to the basic philosophy and principles underlying the new system, the implementation process, the accreditation standards that are used as a basis for assessing service quality and the overall impact of the system on providers. It also sought providers' views about the strengths and limitations of the system and any areas in need of change or improvement. A descriptive design, using in-depth interviews as the method of data collection, was adopted for the study.Participants from three levels of service provision, namely, facilities, organisations and peak bodies were selected on a stratified purposive basis. A total of 45 informants were interviewed. The findings indicated that, overall, as a regulatory approach the accreditation system was generally supported by providers and was regarded as having a number of positive features, particularly in comparison to the previous system. At the same time a number of concerns were identified. These related in particular to the assessment process, specifically the lack of consistency amongst assessors and the self assessment tool, and to the extent of information and guidance provided by the Agency. Concerns regarding the latter's role in relation to, and extent of independence from, the federal government were also identified. The study also found that the introduction of the system had impacted on providers in a variety of ways, both positive and negative, but particularly in terms of the demands on staff and financial resources. A number of 'broader' level factors, such as funding, nursing shortages and other often competing demands (e.g. assessing residents according to the Resident Classification Scale) were also felt to be impacting on providers' capacity to meet the requirements of the system. These concerns, along with concerns about the way in which the system would develop in the future, appear to have created a degree of uncertainty and in some cases apprehension amongst many providers. Although this study has focused on the experiences of Western Australian service providers, evidence from other reviews of the accreditation system where providers' views have been sought has indicated a widespread similarity in perceptions. This suggests, therefore, that there is a need for further review and refinement of certain aspects of the system as it moves into the second round.

The World Wide Web is transitioning from being a mere collection of documents that contain useful information toward providing a collection of services that perform useful tasks. The emerging Web service technology has been envisioned as the next technological wave and is expected to play an important role in this recent transformation of the Web. By providing interoperable interface standards for application-to-application communication, Web services can be combined with component-based software development to promote application interaction and integration within and across enterprises. To make Web services for service-oriented computing operational, it is important that Web services repositories not only be well-structured but also provide efficient tools for an environment supporting reusable software components for both service providers and consumers. As the potential of Web services for service-oriented computing is becoming widely recognized, the demand for an integrated framework that facilitates service discovery and publishing is concomitantly growing.In our research, we propose a framework that facilitates Web service discovery and publishing by combining clustering techniques and leveraging the semantics of the XML-based service specification in WSDL files. We believe that this is one of the first attempts at applying unsupervised artificial neural network-based machine-learning techniques in the Web service domain. Our proposed approach has several appealing features: (1) It minimizes the requirements of prior knowledge from both service providers and consumers, (2) It avoids exploiting domain-dependent ontologies,(3) It is able to visualize the information space of Web services by providing a category map that depicts the semantic relationships among them,(4) It is able to semi-automatically generate Web service taxonomies that reflect both capability and geographic context, and(5) It allows service consumers to combine multiple search strategies in a flexible manner.We have developed a Web service discovery tool based on the proposed approach using an unsupervised artificial neural network and empirically evaluated the proposed approach and tool using real Web service descriptions drawn from operational Web services repositories. We believe that both service providers and consumers in a service-oriented computing environment can benefit from our Web service discovery approach.

The need to address the issue of quality in aged care service provision in Australia has received increasing emphasis in recent decades. Particularly since the 1980s, the federal government has played a key role in ensuring that this is the case through the implementation of various reforms and regulatory strategies. In 1998, the national standards monitoring system which had been in place since the mid 1980s was replaced with a new system based on an accreditation model. In contrast to the former system which was wholly controlled by government and involved one-off inspections by government standards monitors, responsibility for managing the new system has been devolved to an independent body, the Aged Care Standards and Accreditation Agency. One of the Agency's primary functions is to assess compliance with the accreditation standards. A key component of the new system is its emphasis on continuous improvement which has been incorporated into the accreditation standards. As a consequence, the new system requires a much greater level of involvement and commitment by providers than previously. In order to continue receiving government funding all facilities had to be accredited by January 1st 2001. This study represents an evaluation of the accreditation system based on the views and experiences of service providers in Western Australia. It explored a number of issues relating to the basic philosophy and principles underlying the new system, the implementation process, the accreditation standards that are used as a basis for assessing service quality and the overall impact of the system on providers. It also sought providers' views about the strengths and limitations of the system and any areas in need of change or improvement. A descriptive design, using in-depth interviews as the method of data collection, was adopted for the study.
Participants from three levels of service provision, namely, facilities, organisations and peak bodies were selected on a stratified purposive basis. A total of 45 informants were interviewed. The findings indicated that, overall, as a regulatory approach the accreditation system was generally supported by providers and was regarded as having a number of positive features, particularly in comparison to the previous system. At the same time a number of concerns were identified. These related in particular to the assessment process, specifically the lack of consistency amongst assessors and the self assessment tool, and to the extent of information and guidance provided by the Agency. Concerns regarding the latter's role in relation to, and extent of independence from, the federal government were also identified. The study also found that the introduction of the system had impacted on providers in a variety of ways, both positive and negative, but particularly in terms of the demands on staff and financial resources. A number of 'broader' level factors, such as funding, nursing shortages and other often competing demands (e.g. assessing residents according to the Resident Classification Scale) were also felt to be impacting on providers' capacity to meet the requirements of the system. These concerns, along with concerns about the way in which the system would develop in the future, appear to have created a degree of uncertainty and in some cases apprehension amongst many providers. Although this study has focused on the experiences of Western Australian service providers, evidence from other reviews of the accreditation system where providers' views have been sought has indicated a widespread similarity in perceptions. This suggests, therefore, that there is a need for further review and refinement of certain aspects of the system as it moves into the second round.

Human service evaluation has become an important consideration in service delivery due to an increased demand for accountability by funding bodies. Time constraints, financial constraints and political interests, however, influence the implementation and outcomes of evaluation projects. As a result, quantitative methods are most frequently used. Information obtained as the result of quantitative studies which are politically expedient may present a superficial view of a program and overlook the fundamental issues of program delivery which are important to participants. Identification of the valued aspects of program involvement and areas of unmet need from participants' perspectives may remain unknown as a result of seeking information on predetermined and routine program processes in order to maintain the 'status quo'.

Web Service technology is one of the most rapidly developing contemporary technologies. Nowadays, Web Services are being used by a large number of projects and academic studies all over the world. As the use of Web service technology is increasing, it becomes harder to find the most suitable web service which meets the Quality of Service (QoS) as well as functional requirements of the user. In addition, quality of the web services (QoS) that take part in the software system becomes very important. In this thesis, we develop a method to track the QoS primitives of Web Services and an algorithm to automatically calculate QoS values for Web Services. The proposed method is realized within a domain specific web service discovery system, namely DSWSD-S, Domain Specific Web Service Discovery with Semantics. This system searches the Internet and finds web services that are related to a domain and calculates QoS values through some parameters. When a web service is queried, our system returns suitable web services with their QoS values. How to calculate, keep track of and store QoS values constitute the main part of this study.

The vision of the Semantic Web aims at enhancing today's Web in order to provide a more efficient and reliable environment for both providers and consumers of Web resources (i.e. information and services). To deploy the Semantic Web, various technologies have been developed, such as machine understandable description languages, language parsers, goal matchers, and resource composition algorithms. Since the Semantic Web is just emerging, each technology tends to make assumptions about different aspects of the Semantic Web's architecture and use, such as the kind of applications that will be deployed, the resource descriptions, the consumers' and providers' requirements, and the existence and capabilities of other technologies. In order to ensure the deployment of a robust and useful Semantic Web and the applications that will rely on it, several aspects of the technologies must be investigated, such as whether the assumptions made are reasonable, whether the existing technologies allow construction of a usable Semantic Web, and the systematic identification of which technology to use when designing new applications. In this thesis we provide a means of investigating these aspects for service discovery, which is a critical task in the context of the Semantic Web. We propose a simulation and evaluation platform for evaluating current and future Semantic Web technology with different resource sets and consumer and provider requirements. For this purpose we provide a model to represent the Semantic Web, a model of the evaluation platform, an implementation of the evaluation platform as a multi-agent system, and an illustrative use of the platform to evaluate some service discovery technology in a travel scenario. The implementation of the platform shows the feasibility of our evaluation approach. We show how the platform provides a controlled setting to support the systematic identification of bottlenecks and other challenges for new Semantic Web applications. Finally, the evaluation shows that the platform can be used to assess technology with respect to both hardware issues such as the kind and number of computers involved in a discovery scenario, and other issues such as the evaluation of the quality of the service discovery result.

Context MongoDB is an open-source, scalable, NoSQL database that distributes the data over many commodity servers. It provides no single point of failure by copying and storing the data in different locations. MongoDB uses a master-slave design rather than the ring topology used by Cassandra. Virtualization is the technique used for accessing multiple machines in a single host and utilizing the various virtual machines. It is the fundamental technology, which allows cloud computing to provide resource sharing among the users. Objectives Studying and identifying MongoDB, Virtualization on AWS and OpenStack. Experiments were conducted to identify the CPU utilization associated when Mongo DB instances are deployed on AWS and physical server arrangement. Understanding the effect of Replication in the Mongo DB instances and its effect on MongoDB concerning throughput, CPU utilization and latency. Methods Initially, a literature review is conducted to design the experiment with the mentioned problems. A three node MongoDB cluster runs on Amazon EC2 and OpenStack Nova with Ubuntu 16.04 LTS as an operating system. Latency, throughput and CPU utilization were measured using this setup. This procedure was repeated for five nodes MongoDB cluster and three nodes production cluster with six types of workloads of YCSB. Results Virtualization overhead has been identified in terms of CPU utilization and the effects of virtualization on MongoDB are found out in terms of CPU utilization, latency and throughput. Conclusions It is concluded that there is a decrease in latency and increases throughput with the increase in nodes. Due to replication, increase in latency was observed.

Safety is the main concern of the aviation industry. All Air Navigation Service Providers must have a Safety Management System (SMS) which states how safety is handled, promoted and prioritized. By developing Key Performance indicators (KPIs), it is possible to quantify the effectiveness of a SMS, discover potential flaws and improvement measures. This thesis identifies principles behind the SMS, the development of KPIs and suggest potential KPIs for the Swedish air navigation service provider LFVs’ SMS. A literature study was performed and organisation specific documents were analysed to develop potential KPIs within the areas timely compliance with international obligations, competency and adoption and sharing of best practices based on an EASA questionnaire. This work presents a set of 27 performance indicators and recommends 6 as potential KPIs for the three areas together. The KPIs are developed specifically for LFV but could be applicable for other organisations with similar SMS structure and processes. They should be analysed within the organisation and, potentially, have thresholds set before implementation.

The desire amongst media scholars for the fulfilment of the ideal of a universally accessible public sphere by the media is such that virtually every new communications technology that has emerged over the past 1 ~O-odd years such as radio, television or the Internet has been welcomed with enthusiasm - by some - at the prospect of the newest communications innovation bringing about universal access to information. However, the history of communications media tells of the commercialisation of each new medium, from radio to television, and the imposition of barriers to access, based on cost. Access to communications media is open to those people who can afford to pay for them. 111e emergence of the Internet spawned renewed hoped that the public sphere ideal would be realised. 111is new technology seemed more powerful than anything that had come before it. The Internet offered the means whereby one could access a global repository of information, stored on a worldwide network of computer networks, and available 24 hours a day. With the Internet, it was also possible to communicate with people on the other side of the world within seconds, using electronic mail (e-mail). Here was a medium that permitted one to send text and pictures to colleagues and friends within a fraction of the time taken by traditional means such as fax, telephone or post. To enjoy the convenience of the Internet though, one had to have a means of access. In South Africa, access could be gained through a personal computer linked to the Internet either through a network in the workplace or an academic or research institution, or via a telephone link to an Internet Service Provider (ISP). What were the names of the first ISPs to emerge in South Africa? When did they emerge and how did they develop? Did the number of ISPs grow or decline? What do ISPs give access to, at what cost and to whom? Do they provide universal access to information? This study addresses these questions by examining South Africa's leading providers of home dial-up internet access, M-Web and World Online, and by exploring the histories of their emergence and development, within the context of current media trends of concentration, diversification and globalisation.

With the ever-expanding internet, finding new ways to increase the user experience are vital in order to keeping concurrent users on your web application. One way to achieve this could be to implement a Service Worker to unlock more capabilities of a web application. The purpose of this paper is to evaluate what new security vulnerabilities can arise when implementing a Service Worker. This could then be used to evaluate if the technology has evolved far enough to be used by a wider audience of programmers and users. The analysis in this paper will be presented in a security matrix that is based on four experiments and a complementary literature study on web-based attacks. This paper found that some new vulnerabilities must be considered when implementing a Service Worker in a web application. The worst of these is the Living Outside of Scope, which can be used by an attacker to secretly hijack a victim's computer even when the application is shut down. This paper concludes that the technology has evolved far enough so that a secure web application with the use of the Service Worker is possible, but there are still some new vulnerabilities that can become a problem if not considered.

Thesis (DPhil)--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: South African local government literature suggests a historical problem of municipal non-consultation in services identification and provision that goes hand-in-hand with community non-participation in municipal activities, coupled by a ‘culture of non-payment’ for these services. This research, which was conducted between 2002 and 2005 in the city of Johannesburg municipality, had the central purpose of ascertaining the manner and ways in which the city of Johannesburg provides its basic services to the Soweto communities and, in turn, of understanding if communities participate in municipal activities and hold possible attitudes of non-payment for municipal services. In order to attain the research purpose, six research questions were identified through local government theories and literature and advanced. The first set of four questions was aimed at the Soweto communities: How affordable are the basic municipal services to the Soweto communities? What are community’s perceptions of the importance of the various municipal services? Are the communities participating in the services identification and provision? How satisfied are the communities with the service delivery? The second set of two questions was aimed at service providers or the municipal services managers and councillors: What methods does the municipality use in identifying and delivering service? What does the municipality perceive to be their application and enforcement of service quality management standards? The original methodological intent was to interview the Soweto communities and the city of Johannesburg municipal services managers and councillors. 200 Soweto households were indeed interviewed from the eight townships of Chiawelo, Diepkloof, Dobsonville, Dube, Jabulani, Meadowlands, Naledi and Orlando, which were randomly selected. The survey amongst the heads of these 200 households was followed by four focus group meetings at Chiawelo, Dobsonville, Dube and Meadowlands and between five and eleven households participated in the discussions in clarifying survey outcomes. It was only possible, however, to interview three service managers from the city of Johannesburg services utilities Pikitup, Johannesburg Water and the Contract Management Unit. Frustrated attempts to interview municipal councillors in the city of Johannesburg led to obtaining permission for proxy interviews from the MEC of Local Government and Traffic Safety in Mpumalanga municipalities of Govan Mbeki and Emalahleni and the inclusion of the KwaZulu-Natal municipality of Emnambithi. The usage of proxy interviews is thought to be relevant since the perceptions on service provision relate to the application and implementation of the uniform countrywide local government structures and systems. A total of 24 interviews were conducted with the Mpumalanga MEC, the city of Johannesburg service managers (3), councillors (9) and senior municipal administrators (11). In order to confirm or repudiate service provider findings from the Mpumalanga and KwaZulu-Natal municipalities, supplementary interviews were held with persons knowledgeable about service delivery in Soweto between 2002 and 2005. A total of four additional interviews were thus conducted. In the analysis of the community survey data, townships were classified as well-off and worse-off on the basis of household incomes and thus participation in municipal activities, payment of services and other attitudes were compared between the two strata. The findings of the research reveal low levels of ability to pay for municipal services by communities in terms of household incomes. However, the household possessions of the living standard measurement (LSM) utilities indicated otherwise. The use of income as a measure of affordability to pay is suspect in methodological reliability; hence income related findings should be interpreted with caution. The worse-off townships preferred state provision of the basic municipal services. There was less inclination to participate in municipal structures such as ward committees and Integrated Development Plans (IDP) processes by the well-off townships, although they were the least satisfied with service provision and municipal performance. The city of Johannesburg municipality was found to be addressing service backlogs as a method for service identification and prioritisation. The municipality has semi-privatised basic municipal services such as water, electricity and garbage collection through section 21 companies in order to overcome service provision inefficiencies and ineffectiveness. This has devastating effects in terms of the community’s inability to pay, leading to services disconnection. Communities in general, however, believed that service provision has improved through these utilities even though the municipality has not finalised its performance management contracts with the utilities. Whereas the service provider interviews were conducted in Mpumalanga and KwaZulu-Natal, additional telephone interviews with service provision experts for Soweto agreed that municipal challenges throughout the country are generally the same since they operate within relatively new policy frameworks. It is acknowledged, however, that metropolitan municipalities and specifically the city of Johannesburg face some unique challenges too. It is concluded that the central role of the local government as the custodian of basic municipal services cannot be disputed; however, the inefficiencies and ineffectiveness of the market forces require private-public partnerships. It can also be concluded that non-participation is an outcome of, among other things, poor participative capacity within communities, apathy, feelings of distrust of both the municipal institutions and municipal councillors and the lack of information regarding community obligations to municipal institutions. The research recommends the use of similar service utilities in both townships and former white suburban areas in order to overcome the perceptions of the municipal services level disparities that are formed on the basis of townships versus white suburban areas; an overhaul of the municipality’s billing system to overcome its debt and service charges collection problems; ward committee participation capacity improvement for both the municipal councillors and communities and the development and communication of clear guidelines on the roles of regional services management centres. Further research is recommended on, among other things, whether privatisation of municipal services results in better access by all and improves efficiency and payments, and on the functionality and effectiveness of ward committees as vehicles for community participation and in developing new and more reliable socio-economic modelling for assessing community ability to pay for government services.
AFRIKAANSE OPSOMMING: Uit ’n literatuuroorsig van plaaslike regering in Suid-Afrika het dit geblyk dat daar ’n historiese probleem van nie-oorlegpleging by die identifisering en lewering van dienste deur munisipaliteite bestaan. Hierdie probleem gaan hand aan hand met niedeelname aan munisipale aktiwiteite deur gemeenskappe en ’n kultuur van “geenbetaling” vir dienste gelewer. Die hoofdoel van hierdie navorsing, wat tussen 2002 en 2005 in die stad Johannesburg gedoen is, was om vas te stel hoe die stad se munisipaliteit basiese dienste aan Soweto lewer en of daar enige gemeenskapsdeelname aan aktiwiteite is en of gemeenskappe ’n geenbetaling-houding inneem. Om die navorsingsdoel te bereik is ses vrae deur middel van literatuur en teorieë oor plaaslike regering geïdentifiseer. Die eerste vier vrae is gemik op gemeenskappe in Soweto: Hoe bekostigbaar is die basiese munisipale dienste aan die gemeenskappe in Soweto? Wat is die gemeenskap se mening oor die belangrikheid van die onderskeie munisipale dienste? Het gemeenskappe deel aan die identifisering en lewering van dienste? Hoe tevrede is die gemeenskappe met dienslewering? Die laaste twee vrae is gemik op die diensleweraars of munisipaledienstebestuurders en raadslede: Watter metodes gebruik die munisipaliteit om dienste te identifiseer en te lewer? Wat beskou die munisipaliteit as op hulle van toepassing sover dit die afdwingbaarheid van kwaliteitstandaarde in die lewering van dienste en bestuur betref? Oorspronklik was die doel om onderhoude te voer met gemeenskappe in Soweto sowel as munisipaledienste-bestuurders en raadslede van Johannesburg. Onderhoude met hoofde van 200 huishoudings in Soweto is wel gevoer. Hierdie huishoudings is ewekansig uit Chiawelo, Diepkloof, Dobsonville, Dube, Jabulani, Meadowlands, Naledi en Orlando gekies. Die onderhoude is gevolg deur vier fokusgroepvergaderings te Chiawelo, Dobsonville, Dube en Meadowlands, en tussen vyf en elf huishoudings het aan besprekings deelgeneem ten einde duidelikheid te verkry oor bevindinge van die ondersoek. Dit was egter net moontlik om onderhoude met drie dienstebestuurders van die stad Johannesburg te voer, naamlik Pikitup, Johannesburg Water en die Kontrak Bestuursgroep. Verskeie vrugtelose pogings om onderhoude met raadslede te bekom het uiteindelik gelei tot die verkryging van toestemming vir plaasvervangende onderhoude met die LUR vir die Plaaslike Regering sowel as Verkeersveiligheid in die volgende munisipaliteite: Govan Mbeki en Emalahleni in Mpumalanga en Emnambithi in KwaZulu-Natal. Hierdie plaasvervangende onderhoude is as toepaslik beskou, aangesien die menings oor dienslewering te doen het met die toepassing en implementering van die uniforme landswye plaaslikeregering-strukture en -stelsels wat dus op Soweto ook van toepassing is. ’n Totaal van 24 onderhoude is gevoer met die Mpumalanga-LUR (1), die dienstebestuurders van die stad Johannesburg (3), raadslede (9) en senior munisipale administrateurs (11). Om die bevindinge van die Mpumulanga- en KwaZulu-Natal-munisipaliteite te bevestig of te weerlê, is aanvullende onderhoude met persone wat kennis van dienslewering in Soweto het tussen 2002 en 2005 gevoer. Altesaam vier addisionele onderhoude is dus gevoer. Tydens die ontleding van die gemeenskapsdata is gemeenskappe as gegoed of minder gegoed geklassifiseer op grond van huishoudelike inkomste en dus is deelname aan munisipale aktiwiteite, betaling vir dienste en ander gesindhede tussen die twee strata vergelyk. Daar is bevind dat min mense munisipale dienste kan bekostig in terme van huishoudelike inkomste, maar dat huishoudelike besittings wat lewenstandaard bepaal op die teenoorgestelde dui. Die gebruik van huishoudelike inkomste as ’n maatstaf van die vermoë om te betaal is ’n aanvaarbare metode, maar moet tog met omsigtigheid benader word. Die gemeenskap wat die slegste daaraan toe was, verkies dat die staat basiese munisipale dienste voorsien. ’n Laer geneigdheid tot deelname aan munisipale strukture soos wykskomitees en geïntegreerde ontwikkelingsplanne is by die meer gegoede gemeenskappe aangetref, hoewel hulle die grootste ontevredenheid toon met dienslewering en munisipale werkverrigting. Daar is gevind dat die munisipaliteit van die stad Johannesburg die agterstand in dienste aangespreek het as metode om dienste te identifiseer en te prioritiseer. Om die probleem van oneffektiewe en ondoeltreffende dienste te oorkom, maak die munisipaliteit gebruik van artikel 21- maatskappye vir dienste soos water, elektrisiteit en vullisverwydering. Dit lei tot die beëindiging van die dienste van gemeenskappe wat nie kan betaal nie. Oor die algemeen is inwoners egter van mening dat dienste deur hierdie maatskappye verbeter is, hoewel die munisipaliteit nog nie sy prestasiebestuurkontrakte met hierdie maatskappye gefinaliseer het nie. Terwyl die onderhoude met diensverskaffers in Mpumalanga en KwaZulu- Natal gevoer is, is verdere telefoniese onderhoude met kundiges op die gebied van dienslewering in Soweto gevoer. Laasgenoemde het saamgestem dat munisipaliteite regoor die land oor die algemeen voor dieselfde uitdagings te staan kom, omdat hulle binne relatief nuwe beleidsraamwerke funksioneer. Daar word egter toegegee dat stedelike (metropolitaanse) munisipaliteite, en spesifiek die stad Johannesburg, ook met sekere unieke uitdagings te kampe het. Die gevolgtrekking waartoe gekom is, is dat die rol van plaaslike regering as die toesighouer oor basiese munisipale dienste nie betwis kan word nie, hoewel oneffektiwiteit en ondoeltreffendheid privaat vennootskappe vereis. ’n Verdere gevolgtrekking is dat niedeelname onder andere ’n gevolg is van ’n gebrek aan deelnemende kapasiteit binne gemeenskappe, apatie, wantroue in munisipale instellings en raadslede, en ’n gebrek aan inligting rakende gemeenskappe se verpligtinge jeens munisipale instellings. Die navorsing beveel aan dat gelyke dienste gelewer word in swart gemeenskappe en in tradisioneel wit gemeenskappe ten einde die siening dat daar onderskeid getref word, te verander. Daar behoort ook ’n hersiening van die munisipaliteit se rekeningestelsel te wees ten einde die skuldinvorderingsprobleme uit die weg te ruim. Deelnemende kapasiteit vir raadslede en gemeenskappe binne wyke moet verbeter word. Duidelike riglyne oor die rol van streeksdienstebestuursentrums moet ontwikkel en aan gemeenskappe oorgedra word. Verdere navorsing word aanbeveel om te bepaal of die privatisering van dienste tot beter toegang vir almal sal lei en of dit doeltreffendheid en betaling sal verbeter. Die funksionaliteit en effektiwiteit van wykskomitees as meganisme vir gemeenskapsbetrokkenheid sowel as die ontwikkeling van nuwe en meer betroubare sosio-ekonomiese modelle vir die bepaling van gemeenskapsvermoë om vir dienste te betaal, behoort ook ondersoek te word.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Public Management in the Faculty of Business at the Cape Peninsula University of Technology 2014
Thousands of refugees fleeing from surrounding war-torn and destitute African countries come to South Africa hoping to live in safety. Refugee service providers play a major role in providing services to help refugees achieve self-sufficiency soon after entering the country, and the support and assistance required to rebuild their lives and integrate into South African society. The study investigated issues facing refugees in South Africa, particularly in Cape Town, and how service providers assist them in overcoming the hardships of being unprepared in a foreign country. The researcher followed a mixed methods approach, implementing both qualitative and quantitative research methods to explore services provided to refugees in Cape Town by three refugee service providers, namely the Agency for Refugee Education, Skills Training and Advocacy (ARESTA), Cape Town Refugee Centre (CTRC) and Scalabrini Centre of Cape Town (SCCT). Quantitative data was collected by administering a survey questionnaire to 120 refugees, all clients of the selected service providers, to obtain their perceptions about the services they receive. The researcher also conducted semi-structured interviews with senior staff of two of the service providers to gain insight into the services offered and challenges they face in assisting their clients. The study revealed that the majority of clients received assistance, with 75 percent of respondents reporting having received assistance and only 6.67 percent reporting not having received the requested assistance. However, some who had received services indicated too few services were on offer for them to choose from; they took what was offered although these may not have been what they really required. Reasons some refugees do not get services include lack of proper documentation and problems related to the non-availability of the services required by refugees. This is largely due to insufficient funding to provide needed services, and results in refugee service providers either serving only a few people or providing insufficient aid. The study highlights good practices, suggests improvements and concludes with recommendations for the key stakeholders concerned.

In today’s technology industry, cloud refers to servers which can be accessed viainternet, and the software and database applications run on the servers [22]. Whereas cloud computing is a concept of delivering the IT resources via internet which is accessed by the users and companies. In these scenarios OpenStack is the widely used cloud software which controls large pool of IT resources like compute, storage and networking which are managed and provisioned through APIs [11]. In this technology the underlying parts are the transport protocols and web servers used for authenticating and provisioning mechanisms. When stating about its underlying transport protocols, TCP is the default (standard) protocol used behind the functioning of cloud, and HTTP/1.1 version towards actions between Web servers (apache2 and nginx) and browsers [10]. The scope of the thesis is to observe the complexity of replacing TCP with QUIC (Quick UDP Internet Connection) in OpenStack and to observe the performance difference in OpenStack using HTTP/1.1 and HTTP/3. To observe this complexity, Performance Evaluation has been considered the best way in which the performance can be observed from the terminals. The thesis deals with performance of OpenStack with transport protocols from a Web server supporting HTTP/3 feature. We prove that its possible to provide the Keystone API via both HTTP/1.1 and HTTP/3. From our results we see that for simple API access HTTP/3 is faster than the HTTP/1.1 and also when the network is subjected to packet loss. The resultstates that there is a path obtained for OpenStack’s Keystone Service to interact with HTTP/3 and the average request-response time (total time) of HTTP/3 is less than that of HTTP/1.1 for accessing Keystone and Token generation even at defined packet loss rates.

Web applications have become a large segment of the software development domain but their rapid rise in popularity has far exceeded the support in software engineering. There are many tools and techniques for web application development, but the developer must still learn and use many complex protocols and languages. Products still closely bind data operations, business logic, and the user interface, limiting integration and interoperability. This thesis introduces an innovative new presentation service to help web application developers create better applications faster, and help them build high quality web user interfaces. This service acts as a broker between web browsers and applications, adding value with programming-language independent object-oriented technology. The second innovation is a generic graphics applet (GGA) component for the web browser user interface. This light component provides interactive graphics support for the creation of business charts, maps, diagrams, and other graphical displays in web applications. The combination of a presentation service program (BUS) and the GGA is explored in a series of experiments to evaluate their ability to improve web applications. The experiments provide evidence that the BUS and GGA technology enhances web application designs.

In future service markets a selection of functionally equal services is omnipresent. The evolving challenge, finding the best-fit service, requires a distinction between the non-functional service characteristics (e.g., response time, price, availability). Service providers commonly capture those quality characteristics in so-called Service Level Agreements (SLAs). However, a service selection based on SLAs is inadequate, because the static SLAs generally do not consider the dynamic service behaviors and quality changes in a service-oriented environment. Furthermore, the profit-oriented service providers tend to embellish their SLAs by flexibly handling their correctness. Within the SOC (Service Oriented Computing) research project of the Karlsruhe University of Applied Sciences and the Linnaeus University of Sweden, a service broker framework for an optimized web service selection is introduced. Instead of relying on the providers’ quality assertions, a distributed knowledge is developed by automatically monitoring and measuring the service quality during each service consumption. The broker aims at optimizing the service selection based on the past real service performances and the defined quality preferences of a unique consumer.This thesis work concerns the design, implementation and evaluation of appropriate machine learning methods with focus on the broker’s best-fit web service selection. Within the time-critical service optimization the performance and scalability of the broker’s machine learning plays an important role. Therefore, high- performance algorithms for predicting the future non-functional service characteristics within a continuous machine learning process were implemented. The introduced so-called foreground-/background-model enables to separate the real-time request for a best-fit service selection from the time-consuming machine learning. The best-fit services for certain consumer call contexts (e.g., call location and time, quality preferences) are continuously pre-determined within the asynchronous background-model. Through this any performance issues within the critical path from the service request up to the best-fit service recommendation are eliminated. For evaluating the implemented best-fit service selection a sophisticated test data scenario with real-world characteristics was created showing services with different volatile performances, cyclic performance behaviors and performance changes in the course of time. Besides the significantly improved performance, the new implementation achieved an overall high selection accuracy. It was possible to determine in 70% of all service optimizations the actual best-fit service and in 94% of all service optimizations the actual two best-fit services.

A multitude of technologies are presently available for the development of Web applications, each having its strengths and weaknesses. Three of them that are used on the Java 2 platform, Enterprise Edition (J2EE) are introduced in this thesis. They are JavaServer Pages (JSP), JavaServer Pages Standard Tag Library (JSTL), and eXten- sible Markup Language Compiler (XMLC). The functionality that is representative of a generic OpenGIS Consortium (OGC) Web Map Service (WMS) client has been implemented using three approaches that are based on the above technologies: JSP with embedded Java; JSP with JSTL tags; and XMLC. The functionality includes producing a custom map with layers retrieved from different WMS servers; manipulating views of the map; querying information about features of a location selected on the map by the user, and so on. In this thesis we evaluate and compare the three approaches from the perspective of application architecture, development, and maintenance, based on our implementation experience. We also present the design and setting up of a local Web mapping system on which the WMS client being implemented has been running.

Les services géolocalisés (LBS) sont destinés à délivrer de l'information adéquate aux utilisateurs quelque soit le temps et l'endroit et ceci en se basant sur leur profil, contexte et position géographique. A travers n'importe quelle application dans ce domaine, par exemple m-tourisme, les utilisateurs souhaitent toujours recevoir une réponse rapide et précise en se déplaçant. Cependant, la qualité de service proposée par les fournisseurs cartographiques actuels (i.e. Google Maps, Bing, Yahoo Maps, Mappy ou Via Michelin) dépend de leurs données géographiques. En général, ces données sont stockées de plusieurs bases de données géographiques (BDG) dans le monde entier. D'autre part, le nombre croissant des différentes BDG couvrant la même zone géographique et la récupération des données/métadonnées non erronées pour un service quelconque, impliquent de nombreux raisonnements et de contrôles d'accès aux BDG afin de résoudre les ambiguïtés dues à la présence des objets homologues dupliqués sur l'écran mobile. Mon travail consiste à permettre cette intégration cartographique pour les applications mtourisme et ceci en récupérant les informations spatiales/non-spatiales (noms, positions géographiques, catégorie du service, détails sémantiques et symboles cartographiques) de plusieurs fournisseurs. Cependant, ceci peut conduire à visualiser des objets dupliqués pour le même point d'intérêt et causer des difficultés au niveau de la gestion des données. En outre, l'utilisateur sera dérouté par la présence de résultats multiples pour un même point. Donc, mon but ultime sera de générer automatiquement une carte unique intégrant plusieurs interfaces des fournisseurs sur laquelle les objets homologues seront intégrés avant de les visualiser sur l'écran mobile. Nos nouveaux concepts, basés sur certains algorithmes de fusion, sur l'ontologie pour assurer l'intégration au niveau sémantique et cartographique, sur l'orchestration des géo web services, sont implémentés dans des prototypes modulaires et évalués.

The educational community is increasingly concerned about the limitations of traditional teacher education programs to support teachers&rsquo
professional development. Beside the theoretical knowledge, the importance of the experience cannot be debated. The main problem of the teacher education institutions is that they fail to close the gap between the theoretical principles taught in the faculties of education and the experiences of teachers in the classrooms. Microteaching is the most popular method to prepare the PSTs for real-world teaching profession. However, literature showed that there are some barriers that PSTs face during the microteaching process, including limited and unreflective peer-feedback (Huang, 2001). In order to facilitate PSTs&rsquo
peer-interaction and reflective thinking during their microteaching process, a web-based video analysis environment was designed. In addition, in teacher education observation has a critical place. The purpose of this study is to examine the effects of question prompts embedded within this environment on PSTs&rsquo
reflective thinking and self-efficacy levels. For this purpose, a true experimental study was designed and applied. 55 pre-service teachers were enrolled in this study. First finding of this study is that the use of question prompts embedded in a web-based video analysis system have a positive significant effect on pre-service teachers'
reflective thinking level. Second finding of this study is that the use of question prompts embedded in a web-based video analysis system did not have a significant effect on pre-service teachers'
self-efficacy. However, there was a significant linear trend indication for all types of self-efficacy factors for both control and experimental group over the time. For both groups this linear trend showed that self-efficacy scores of instructional strategies, classroom management, and student engagement developed over the time.

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FACEPE
Composite web services, also known as mashups, are useful to build added-value products in the web. Cloud computing environments have been widely used for hosting web services due to the possibility of increasing or decreasing available resources through automatic mechanisms (i.e.: auto scaling). Such elastic behavior ease the task of reaching satisfactory performance on peaks of demand without wasting resources. It is hard to determine the right components to tune such systems performance when eventually needed. This study evaluates the performance of auto scaling mechanisms for private clouds hosting an event recommendation web service. A hierarchical modeling approach is used to cope with the complexity of such a system, and represent specific details of these mechanisms. Our study applies parametric sensitivity analysis from several performance metrics of the models, such as mean execution time of the auto scaling monitoring, mean time of VMs instantiation, and the mean response time perceived by the web service user. We also have carried a General Full Factorial Experiment, in order to calculate the relevance and effects of each factor involved in the processes of auto scaling and virtual machines (VMs) instantiation. For the auto scaling monitoring, we analyze the factors: collection period of a metric, number of monitored virtual machines, and the time of monitoring of a metric. Regarding the instantiation process, the following factors have been chosen: VM type, VM image size, and VM caching. This analysis allows checking the impact of parameters on the system response time and pointing out effective ways for improvement of performance.
Serviços web compostos, também conhecidos como mashups, são úteis para construir produtos de valor agregado na web. Ambientes de computação em nuvem têm sido amplamente utilizados para hospedar serviços web, devido à possibilidade de aumentar ou diminuir os recursos disponíveis através de mecanismos automáticos (i.e.: escala automática). Tal comportamento elástico facilita a tarefa de alcançar um desempenho satisfatório nos picos de demanda sem desperdiçar recursos. É difícil determinar os componentes certos para ajustar o desempenho desses sistemas eventualmente, quando necessário. Este estudo avalia o desempenho dos mecanismos de escala automática e elasticidade para nuvens privadas hospedando um serviço web de recomendação de eventos. Uma abordagem de modelagem hierárquica é utilizada afim de lidar com a complexidade de tal sistema, e representar detalhes específicos desses mecanismos. Nosso estudo aplicou análise de sensibilidade paramétrica a partir de várias métricas de desempenho dos modelos, tais como o tempo médio de execução do monitoramento de escala automática, tempo médio da instanciação de VMs e o tempo médio da resposta percebida pelo usuário do serviço web. Realizamos também um Experimento Geral Fatorial Completo, com o objetivo de calcular os efeitos e relevâncias de cada fator envolvido nos processos escala automática e instanciação de máquinas virtuais (virtual machines - VMs). Para o monitoramento de escala automática, analisamos os fatores: período de coleta de uma métrica, número de máquinas virtuais monitoradas, e o tempo de monitoração de uma métrica. Quanto ao processo de instanciação, os seguintes fatores foram escolhidos: tipo de VM, tamanho da imagem da VM, e cache da VM. Estas análises permitem verificar o impacto dos parâmetros sobre o tempo de resposta do sistema e apontar formas eficazes de melhoria do desempenho.

Workflow systems orchestrate various business tasks to attain an objective. Web services can be leveraged to handle individual tasks. Before anyone intends to leverage service components, it is imperative and essential to evaluate the trustworthiness of these services. Therefore, choosing a trustworthy service has become an important decision while designing a workflow system. Trustworthiness can be defined as the likelihood of a service functioning as it is intended. Selection of a service that satisfies business goals involves collecting relevant information such as security mechanisms, reliability, performance and availability. It is important to arrive at total trustworthiness, which incorporates all of the above mentioned multi-facet values relevant to a service. These values can be gathered and analyzed to derive the total trustworthiness of a service. Measuring trustworthiness of a service involves arriving at a suitable value that would help an end-user make a decision for the given business settings. The primary focus of this thesis is to gather relevant details and measure trustworthiness based on inputs provided by the user. A conceptual model was developed after extensive literature review to identify factors that influence trustworthiness of a service. A mechanism was created to gather concept values for a given service and utilize those values to calculate trustworthiness index value. A proof-of-concept prototype was also developed. The prototype is a web-based application that implements the mechanism to measure the trustworthiness of the service. The prototype was evaluated using a scenario-based analysis method to demonstrate the utility of the trustworthiness mechanism using three different scenarios. Results of the evaluation shows that trustworthiness is a multidimensional concept, the relevant conceptual values can be collected, a trustworthiness index value can be calculated based on the gathered concepts, and a trustworthiness index can be interpreted to select the most relevant service for a given requirement.

Many students in primary and secondary schools are impacted by a chronic health condition. Researchers have postulated that interprofessional collaboration between medical and mental health providers can be beneficial in improving the academic, behavioral, and social-emotional outcomes of students with chronic health conditions (Drotar, Palermo, & Barry, 2003; Shapiro & Manz, 2003). An emerging area of focus is on the school-based collaboration between school nurses and school psychologists regarding supporting students with chronic health conditions. This study investigated school nurses’ perceptions of the benefit of collaborating with school psychologists, school nurses’ awareness of the roles of school psychologists, the frequency of collaborative practices, the relationship between the awareness of roles and frequency of collaborative practices, and the barriers and facilitators to the collaborative process. A total of 1,054 school nurses were recruited from National Board for Certification of School Nurses to participate in the study, and 240 surveys were completed (23% response rate). Findings indicate that school nurses perceive the collaborative practice as being beneficial for supporting students with chronic health conditions. Additionally, school nurses were able to accurately identify many roles of school psychologists. Despite school nurses perceiving collaboration with school psychologists as beneficial, and being aware of the roles of school psychologists, the frequency of collaboration between school nurses and school psychologists was low. Further analysis found a significant and positive relationship between awareness of the roles and collaborative practices. Benefits of the collaborative process included cross-disciplinary problem solving and the opportunity to share resources.

Atualmente, pesquisadores e acadêmicos têm beneficiado-se muito com o crescimento acelerado das tecnologias Web, pois os resultados de pesquisa podem ser publicados e acessados eletronicamente tão logo a mesma tenha sido realizada. Esta possibilidade é vantajosa na medida em que minimiza as barreiras de tempo e espaço associadas à publicação tradicional. Neste contexto, surgem as Bibliotecas Digitais como repositórios de dados que, além dos documentos digitais propriamente ditos, ou de apontadores para estes documentos, armazenam os metadados associados. Para permitir que diferentes Bibliotecas Digitais possam interoperar surgiu a Open Archives Initiative (OAI) e, para resolver a questão da padronização dos metadados utilizados pelos repositórios, foi criado o formato Dublin Core (DC). Por outro lado, a enorme quantidade de documentos digitais disponíveis na Web tem causado o fenômeno conhecido como “sobrecarga de informação”. Com o objetivo de suprir esta dificuldade, Sistemas de Recomendação têm sido propostos e desenvolvidos. Estes sistemas visam prover uma interface alternativa para tecnologias de filtragem e recuperação de informações, tendo como foco a predição daqueles itens ou partes da informação que o usuário acharia interessante e útil. Portanto, os Sistemas de Recomendação atuam baseados em personalização da informação sendo que as predições geralmente são realizadas utilizando-se um perfil de cada usuário. A personalização está relacionada com o modo pelo qual a informação e serviços podem ser ajustados às necessidades específicas de um usuário ou comunidade. Esta dissertação descreve um Sistema de Recomendação de artigos científicos, armazenados em bibliotecas digitais. Este sistema é dirigido à comunidade científica da área da Ciência da Computação. Tecnologicamente, o sistema proposto foi desenvolvido sob a perspectiva da Web Semântica, à medida que faz uso de suas tecnologias emergentes tais como: uso de metadados padrão para a descrição de documentos - Dublin Core, uso do padrão XML para a descrição do perfil do usuário - Currículo Lattes, e provedores de serviços e de dados (OAI) envolvidos no processo de geração das recomendações. Este trabalho ainda apresenta e discute alguns resultados de experimentos baseados em avaliações quantitativas e qualitativas de recomendações geradas pelo sistema.
Currently, researchers and academics have been benefited by the expressive growth of web technologies, due to the possibility of publishing and accessing research results as soon as they are achieved. This possibility is advantageous as it minimizes the time and space barriers that traditional publications present. In this context, Digital Libraries emerged as data repositories that, beyond digital documents or links to them, store associated metadata. To allow the interoperability among different Digital Libraries, the Open Archives Initiative (OAI) was defined and, to solve the problem of metadata standardization, the Dublin Core standard (DC) was created. On the other hand, the great amount of available digital documents in the Web has caused the phenomenon known as “information overload”. In order to avoid this difficulty, Recommender Systems have been proposed and developed. These systems intend to provide an alternative interface for information filtering and retrieval technologies, focusing on the prediction of items or information parts that are interesting and useful for the user. Therefore, Recommender Systems act based on information personalization, and the predictions are generally generated using each user’s profile. The personalization is related to the way the information and the provided services can be adjusted to the specific necessities of a user or community. This dissertation describes a Recommender System for scientific articles stored in digital libraries. This system is geared towards the Computer Science scientific community. Technologically, the proposed system was developed under the Semantic Web perspective, as it explores its emergent technologies such as: use of standard metadata for document description - Dublin Core, use of the XML standard for users’ profile description - Lattes Curriculum Vitae, and services and data providers (OAI) involved on the recommendations generation process. In addition, this work presents and discusses some experimental results; the experiments are based on quantitative and qualitative evaluations of recommendations generated by the system.

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Os Web Services são componentes de software que se utilizam de tecnologias e protocolos abertos: XML, SOAP, WSDL e UDDI, para fornecer seus serviços. Atualmente, os Web Services surgem como alternativa para melhorar a comunicação entre os sistemas. Esta dissertação apresenta uma reestruturação arquitetural de Web Service - em funcionamento há quatro anos, cuja finalidade do seu serviço visa possibilitar que operações DML sejam realizadas em diferentes bases de dados de forma transparente para os usuários - fazendo uso de refatoração e padrões de projetos, garantindo que os fatores de qualidade: manutenibilidade, confiabilidade, eficiência e portabilidade, sejam mantidos. Os objetivos propostos podem ser sintetizados no entendimento e caracterização das funcionalidades e das tecnologias que envolvem os Web Services; estudos e pesquisas para descobrir quais padrões de projetos e refatoração podem ser utilizados na implementação do Web Services, possibilitando desta forma que boas práticas de desenvolvimento sejam adotadas; definir quais fatores de qualidade podem ser utilizados no processo de validação, além de, realizar avaliações e testes de Web Service fazendo uso de ferramentas Open Source; e finalmente, analisar se os resultados obtidos após o uso destes padrões na implementação do Web Service são satisfatórios. Para alcançar os objetivos propostos foi realizada uma análise da arquitetura do Web Service, por meio da engenharia reversa e análise de código. Após esta análise, refatorações e padrões de projetos foram definidos e utilizados na nova arquitetura para a implementação do novo Web Service, com o intuito de prover e garantir os fatores de qualidade: manutenibilidade, confiabilidade, eficiência e portabilidade. E por fim, testes de desempenho, carga/stress e funcional foram realizados com auxílio de ferramentas Open Source, JMeter e SoapUI, nos dois Web Services, para posteriormente seus resultados serem analisados. Os resultados obtidos, após a realização de teste e avaliação comparativa entre os dois Web Services, demonstraram uma melhora na qualidade dos serviços fornecidos pelo Web Service reestruturado, além de proporcionar redução de custo de manutenção. Assim sendo, este estudo constatou que refatoração e padrões de projetos podem ser utilizados na implementação de Web Service.
Web Services are software components that use open technologies and protocols like XML, SOAP, WSDL and UDDI, to provide its services. Currently, Web Services are an alternative to improve communication between the systems. This dissertation presents a Web Service architectural restructuring – in operation for four years, for the purpose of its service aims to enable DML operations are performed on different databases transparently to users – making use of refactoring and design patterns, ensuring that the factors of quality: maintainability, reliability, efficiency and portability are kept. The objectives proposed can be synthesized in the understanding and characterization of the features and technologies involving Web Services; study and research to find out which design patterns and refactoring can be used in the implementation of the Web Service, enabling this way that good development practices are adopted. We also identify quality factors that can be used in the validation process, as well as we carry out evaluations and testing of Web Service using Open Source tools. Finally, we analyze the results obtained after the use of these standards in the implementation of Web Service are satisfactory. To achieve the proposed was conducted an analysis of the architecture of the Web Service, by means of reverse engineering and code analysis. After this step, design patterns and refactoring have been defined and used in the new architecture for the implementation of the new Web Service, in order to provide and ensure the factors of quality: maintainability, reliability, efficiency and portability. Finally, performance testing, load/stress and functional were performed with the help of Open Source tools, JMeter and SoapUI Web Services, two for later results are analyzed. The results, after testing and benchmarking between the two Web Services, showed and improvement in the quality of services provided by the Web Service restructured, in addition to providing maintenance cost reduction. Therefore, this study found that refactorings and design patterns can be used in implementing the Web Service.

The growth of eCommerce is being hampered by a lack of trust between providers and consumers of Web-based services. While Web trust issues have been addressed by researchers in many disciplines, a comprehensive approach has yet to be established. This thesis proposes a conceptual trust-profiling framework???W3TF???which addresses issues of trust and user confidence through a range of new user-centred trust measures???trust categories, trust domains, transitivity of trust, fading factor analysis, standalone assessment, hyperlinked assessment and relevance assessment. While others now use the concept of transitivity of trust, it was first introduced by this research in 1998. The thesis also illustrates how W3TF can narrow the gap/disconnection between the hierarchical PKI trust environment and the horizontal Web referral environment. The framework incorporates existing measures of trust (such as Public Key Infrastructure), takes account of consumer perceptions by identifying trust attributes, and utilises Web technology (in the form of metadata), to create a practical, flexible and comprehensive approach to trust assessment. The versatility of the W3TF is demonstrated by applying it to a variety of cases from trust literature and to the hypothetical case study that provided the initial stimulus for this research. It is shown that the framework can be expanded to accommodate new trust attributes, categories and domains, and that trust can be ???weighed??? (and therefore evaluated) by using various mathematical formulae based on different theories and policies. The W3TF addresses identified needs, narrows the gaps in existing approaches and provides a mechanism to embrace current and future efforts in trust management. The framework is a generic form of trust assessment that can help build user confidence in an eCommerce environment. For service providers, it offers an incentive to create websites with a high number of desired trust attributes. For consumers, it enables more reliable judgments to be made. Hence, Web trust can be enhanced.

The promise of service oriented computing, and the availability of Web services promote the delivery and creation of new services based on existing services, in order to meet new demands and new markets. As Web and internet based services move into Clouds, inter-dependency of services and their complexity will increase substantially. There are standards and frameworks for specifying and composing Web Services based on functional properties. However, mechanisms to individually address non-functional properties of services and their compositions have not been well established. Furthermore, the Cloud ontology depicts service layers from a high-level, such as Application and Software, to a low-level, such as Infrastructure and Platform. Each component that resides in one layer can be useful to another layer as a service. It hints at the amount of complexity resulting from not only horizontal but also vertical integrations in building and deploying a composite service. To meet the requirements and facilitate using Web services, we first propose a WSDL extension to permit specification of non-functional or Quality of Service (QoS) properties. On top of the foundation, the QoS-aware framework is established to adapt publicly available tools for Web services, augmented by ontology management tools, along with tools for performance modeling to exemplify how the non-functional properties such as response time, throughput, or utilization of services can be addressed in the service acquisition and composition process. To facilitate Web service composition standards, in this work we extended the framework with additional qualitative information to the service descriptions using Business Process Execution Language (BPEL). Engineers can use BPEL to explore design options, and have the QoS properties analyzed for the composite service. The main issue in our research is performance evaluation in software system and engineering. We researched the Web service computation as the first half of this dissertation, and performance antipattern detection and elimination in the second part. Performance analysis of software system is complex due to large number of components and the interactions among them. Without the knowledge of experienced experts, it is difficult to diagnose performance anomalies and attempt to pinpoint the root causes of the problems. Software performance antipatterns are similar to design patterns in that they provide what to avoid and how to fix performance problems when they appear. Although the idea of applying antipatterns is promising, there are gaps in matching the symptoms and generating feedback solution for redesign. In this work, we analyze performance antipatterns to extract detectable features, influential factors, and resource involvements so that we can lay the foundation to detect their presence. We propose system abstract layering model and suggestive profiling methods for performance antipattern detection and elimination. Solutions proposed can be used during the refactoring phase, and can be included in the software development life cycle. Proposed tools and utilities are implemented and their use is demonstrated with RUBiS benchmark.

In recent years the service-oriented design paradigm has enabled applications to be built by incorporating third party services. With the increasing popularity of this new paradigm, many companies and organizations have started to adopt this technology, which has resulted in an increase of the number and variety of third party providers. With the vast improvement of global networking infrastructure, a large number of providers offer their services for worldwide clients. As a result, clients are often presented with a number of providers that offer services with the same or similar functionalities, but differ in terms of non-functional attributes (or Quality of Service – QoS), such as performance. In this environment, the role of provider recommendation has become more important - in assisting clients in choosing the provider that meets their QoS requirement.
In this thesis we focus on provider recommendation based on one of the most important QoS attributes – performance. Specifically, we investigate client-perceived performance, which is the application-level performance measured at the client-side every time the client invokes the service. This performance metric has the advantage of accurately representing client experience, compared to the widely used server-side metrics in the current frameworks (e.g. Service Level Agreement or SLA in Web Services context). As a result, provider recommendation based on this metric will be favourable from the client’s point of view.
In this thesis we address two key research challenges related to provider recommendation based on client-perceived performance - performance assessment and performance prediction. We begin by identifying heterogeneity factors that affect client-perceived performance among clients in a global Internet environment. We then perform extensive real-world experiments to evaluate the significance of each factor to the client-perceived performance.
From our finding on heterogeneity factors, we then develop a performance estimation technique to address performance assessment for cases where direct measurements are unavailable. This technique is based on the generalization concept, i.e. estimating performance based on the measurement gathered by similar clients. A two-stage grouping scheme based on the heterogeneity factors we identified earlier is proposed to address the problem of determining client similarity. We then develop an estimation algorithm and validate it using synthetic data, as well as real world datasets.
With regard to performance prediction, we focus on the medium-term prediction aspect to address the needs of the emerging technology requirements: distinguishing providers based on medium-term (e.g. one to seven days) performance. Such applications are found when the providers require subscription from their clients to access the service. Another situation where the medium-term prediction is important is in temporal-aware selection: the providers need to be differentiated, based on the expected performance of a particular time interval (e.g. during business hours). We investigate the applicability of classical time series prediction methods: ARIMA and exponential smoothing, as well as their seasonal counterparts – seasonal ARIMA and Holt-Winters. Our results show that these existing models lack the ability to capture the important characteristics of client-perceived performance, thus producing poor medium-term prediction. We then develop a medium-term prediction method that is specifically designed to account for the key characteristics of a client-perceived performance series, and to show that our prediction methods produce higher accuracy for medium-term prediction compared to the existing methods.
In order to demonstrate the applicability of our solution in practice, we developed a provider recommendation framework based on client-perceived performance (named PROPPER), which utilizes our findings on performance assessment and prediction. We formulated the recommendation algorithm and evaluated it through a mirror selection case study. It is shown that our framework produces better outcomes in most cases, compared to country-based or geographic distance-based selection schemes, which are the current approach of mirror selection nowadays.

Les concepts d’architecture orientée service (SOA) ainsi que tout une panoplie de technologies «en tant que service» (XaaS) sont utilisés quasiment partout de nos jours, et l’organisation optimisée d’activités synchronisées devient un défi important. Dans le but de proposer à l’utilisateur final un service sécuritaire et fiable sans compromettre la qualité, les questions concernant la vérification et la validation des compositions des services deviennent d’un grand intérêt tant théorique que pratique. Dans les autres travaux traitant du sujet, de nombreux modèles et techniques sont proposés, mais la plupart mettent l’accent sur les aspects fonctionnels ou non-fonctionnels pris séparément, alors que l’intégration de ces paramètres en un modèle formel unifié reste un problème qui doit être résolu – ce qui est devenu par conséquent un des objectifs fondamentaux de cette thèse. Dans notre travail, nous réfléchissons aux problèmes de la vérification et de l’optimisation des compositions des services web. Tout ceci est étudié dans l’optique de la fonctionnalité des systèmes, de leur qualité et de la sécurité des compositions. Il a été prouvé que les modèles à états finis sont utiles à des fins de tests et de vérification, de même que pour le contrôle qualité à chaque étape du développement du service. C’est pour cette raison que nous proposons d’utiliser le modèle de machine temporisée à états finis (TFSM) pour intégrer une description fonctionnelle du service avec les paramètres de sécurité et de qualité liées au temps. L’extension du modèle permettra alors d’interpréter adéquatement le non-déterminisme significatif causé par un manque d’observabilité ou/et de contrôle sur les services tiers. Dans le but d’optimiser les compositions des systèmes, nous proposons une méthode pour dériver la solution la plus globale contenant tous les composants autorisés pour la mise en œuvre du service, basée sur la résolution de l’équation parallèle du TFSM. Ensuite, les techniques pour extraire des solutions restreintes avec les propriétés requises (paramètres de temps minimisé/maximisé, interblocages actifs ou passifs de sécurité, similarité avec le composant d’origine donné, etc.) ont été proposées. Dans le cas où les spécifications d’un service composite consistent en un ensemble d’exigences fonctionnelles, éventuellement renforcées par des exigences de qualité, nous proposons une technique de minimisation de l’ensemble, dans le respect du composant à optimiser. L’application des résultats obtenus à la découverte et à la mise en place de composants plus efficaces, ainsi que l’extension du modèle à des modes de communication plus complexes font partie des sujets possibles pour des études futures
Service-oriented architecture (SOA) together with a family of Everything-as-a-Service (XaaS) concepts nowadays are used almost everywhere, and the proper organization of collaborative activities becomes an important challenge. With the goal of bringing to the end-user safe and reliable service with the guaranteed level of quality, issues of service compositions verification and validation become of high practical and theoretical interest. In the related works, numerous models and techniques are proposed, but mostly focused on functional and non-functional issues in isolation, while integration of these parameters within unified formal framework still remains a problem to be solved – and therefore became one of the core objectives of this thesis. In our work, we address the problems of web service composition verification and optimization with respect to functional, quality and safety properties of the composition. Finite state models are proven to be useful for testing and verification purposes as well as for service quality evaluation at each step of service development. Therefore, we propose to use the model of Finite State Machine with Timeouts (TFSM) for integrating functional service description with time-related quality and safety parameters, and derive the extension of the model in order to adequately inherit significant nondeterminism due to the lack of observability and control over third-party component services. For the purpose of component optimization in the composition, we propose a method for deriving the largest solution containing all allowed component service implementations, based on solving TFSM parallel equation. Further, techniques for extracting restricted solutions with required properties (minimized/maximized time parameters, deadlock- and livelock-safety, similarity to the initially given component, etc.) have been proposed. In cases when the specification of a composite service is provided as a set of functional requirements, possibly, augmented with quality requirements, we propose a technique to minimize this set with respect to the component under optimization. Application of the obtained results for more efficient candidate component services discovery and binding, alongside with extending the framework for more complex distributed modes of communications, are among the topics for the future work

Este projeto de mestrado aborda a utilização de recursos daWeb Semântica na seleção de informações sobre Web Services no registro UDDI (Universal Description, Discovery, and Integration). Esse registro possui a limitação de apenas armazenar informações funcionais de Web Services. As informações não funcionais que incluem as informações de qualidade de serviço (QoS - Quality of Service) não são contempladas e dessa forma dificulta a escolha do melhor serviço pelos clientes. Neste projeto, a representação da base de conhecimento com informações sobre os provedores, clientes, acordos, serviços e a qualidade dos serviços prestados foi feita por meio de uma ontologia. Essa ontologia é utilizada pelo módulo UDOnt-Q (Universal Discovery with Ontology and QoS) que foi projetado para servir de plataforma para algoritmos de busca e composição de serviços com qualidade. Embora a utilização de semântica possa ser empregada para a composição e automatização de serviços, o foco deste trabalho é a garantia de qualidade de serviço em Web Services. Os algoritmos desenvolvidos empregam recursos da Web Semântica para classificar e selecionar os Web Services adequados de acordo com as informações de qualidade que estão armazenados na ontologia. O módulo e os algoritmos foram submetidos a avaliações de desempenho que revelaram problemas de desempenho com relação a abordagem adotada durante o processo de inferência da ontologia. Tal processo é utilizado para a classificação das informações dos elementos presentes na ontologia. Contudo, uma vez que as informações foram inferidas, o processo de busca e seleção de serviços comprovou a viabilidade de utilização do módulo e de um dos seus algoritmos de seleção
This master project addresses the use of Semantic Web resources in the selection of information about Web Services in UDDI registry (Universal Description, Discovery, and Integration). This registry has the limitation of only storing functional information of Web Services. The nonfunctional information that includes the quality of service information (QoS - Quality of Service) is not covered and thus it is complicate to choose the best service for customers. In this project, the representation of the knowledge base with information about the providers, customers, agreements, services and quality of services has been made through an ontology. This ontology is used by the module UDOnt-Q (Universal Discovery with Ontology and QoS) that was designed to serve as a platform for search algorithms and composition of services with quality. Although the use of semantics can be adopted for the composition and automation of services, the focus of this work is to guarantee quality of service in Web Services. The developed algorithms employ SemanticWeb resources to classify and select the appropriate Web Services according to the quality information that is stored in the ontology. The module and the algorithms have been subjected to performance evaluations that revealed performance problems in relation to the approach taken during the ontology inference process. This process is used for classification of information of the elements present in the ontology. However, since the information was inferred, the process of search and selection services proved the viability of using the module and one of its selection algorithms

Business transactions (a.k.a., business conversations) are series of message exchanges that occur between software applications coordinating to achieve a business objective. Web service has been proven to be a promising technology in supporting business transactions. Business transaction can either be long-running or short-lived. A transaction whether in a database or web service paradigm consists of an “all-or-nothing” property. A transaction could either succeed or fail. Web Service Atomic Transactions (WS-AT) is a specification that currently supports Two-Phase Commit (2PC) protocol in a short-lived transaction. WS-AT is developed by OASIS–a standards development organization. However, not all business process scenarios require a 2PC, in that case, just a One-Phase Commit (1PC) would be sufficient. But unfortunately, WS-AT currently does not support 1PC optimization. The ideal scenario where 1PC can be used instead of 2PC is when there is only a single participant. Short-lived transactions involving only one participant can commit without requiring initial “prepare” phase. Thus, there is no overhead to check whether the participant is prepared to either commit or rollback. This research focuses on designing a mechanism that can add 1PC support in WS-AT. The technical implementation of this mechanism is developed by using JBoss Transaction API. As a part of this thesis, 1PC mechanism for a single participant scenario was implemented. This mechanism optimizes the web service transaction process in terms of overhead and performance in terms of execution time. The technical implementation solution for 1PC mechanism was evaluated using three different business process scenarios in a controlled experiment as a presence or absence test. Evaluation results show that 1PC mechanism has a lower mean for execution time and performed significantly better than 2PC mechanism. Based on the contributions made by this thesis, we recommend OASIS to consider including 1PC mechanism as a part of the WS-AT specification.

Most epidemiological systems described in the literature are built for evaluation and analysis of specific diseases, such as Influenza-like-illness. The modeling environments that support these systems are implemented for specific diseases and epidemiological models. Hence they are not reusable or extendable. This thesis focuses on the design and development of an integrated analytical environment with flexible data integration methodologies and multi-level web services for evaluation and forecasting of various epidemics in different regions of the world. The environment supports analysis of epidemics based on any combination of disease, surveillance sources, epidemiological models, geographic regions and demographic factors. The environment also supports evaluation and forecasting of epidemics when various policy-level and behavioral interventions are applied, that may inhibit the spread of an epidemic. First, we describe data integration methodologies and schema design, for flexible experiment design, storage and query retrieval mechanisms related to large scale epidemic data. We describe novel techniques for data transformation, optimization, pre-computation and automation that enable flexibility, extendibility and efficiency required in different categories of query processing. Second, we describe the design and engineering of adaptable middleware platforms based on service-oriented paradigms for interactive workflow, communication, and decoupled integration. This supports large-scale multi-user applications with provision for online analysis of interventions as well as analytical processing of forecast computations. Using a service-oriented architecture, we have provided a platform-as-a-service representation for evaluation and forecasting of epidemics. We demonstrate the applicability of our integrated environment through development of the applications, DISIMS and EpiCaster. DISIMS is an interactive web-based system for evaluating the effects of dynamic intervention strategies on epidemic propagation. EpiCaster is a situation assessment and forecasting tool for projecting the state of evolving epidemics such as flu and Ebola in different regions of the world. We discuss how our platform uses existing technologies to solve a novel problem in epidemiology, and provides a unique solution on which different applications can be built for analyzing epidemic containment strategies.
Ph. D.

Esta dissertação de mestrado aborda um estudo sobre a caracterização de cargas de trabalho para Web services por meio da análise de Documentos WSDL (Web Service Description Language). Esses documentos, que representam a interface para os serviços, foram obtidos na Web e seus conteúdos analisados estatisticamente. A metodologia utilizada para alcançar a caracterização desejada, constitui-se da coleta e análise dos dados de 1346 arquivos WSDL válidos. O resultado do estudo proposto nesta dissertação contribui para a avaliação de desempenho no que diz respeito a caracterizar os diversos aspectos das cargas de trabalho de Web services. Dentre os dados obtidos ressaltam-se as porcentagens da ocorrência de algumas características tais como o número de operações, tipos de Binding, quantidade de parâmetros de entrada e saída e tipos de dados mais utilizados. Para auxiliar na busca e avaliação das características das WSDLs uma nova ferramenta denominada WSDLAnalyzer é proposta e implementada
This MSc dissertation approaches a study on workload characterization for web services by means of the analysis of WSDL (Web Service Description Language) documents. These documents, that represent the interface to the services, were all obtained in the web and their contents were statistically analyzed. The methodology used to reach the desired characterization comprises the collection and analysis of 1346 WSDL valid files. The result of the study proposed in this dissertation contributes to the performance evaluation of web services in terms of characterizing the several aspects of the workloads. Among the data obtained, the percentage of occurrences of some features, such as the number of operations, the types of binding, the amount of input and output parameters and the more used data types, are highlighted. To support the search and evaluation of the WSDL features a new tool, named WSDLAnalyzer, is proposed and implemented

The Service Worker is a programmable proxy that allows the clients to keep offline parts of websites or even the whole domains, receive push notifications, have back-ground synchronization and other features. All of these features are available to the user without having to install an application - the user only visits a website. The service worker has gained popularity due to being a key component in the Progressive Web Applications (PWAs). PWAs have already proven to drastically increase the number of visits and the duration of browsing for websites such as Forbes [1], Twitter [2], and many others. The Service Worker is a powerful tool, yet it is hard for clients to understand the security implications of it. Therefore, all modern browser install the service workers without asking the client. While this offers many conveniences to the user, this powerful technology introduces new security risks. This thesis takes a closer look at the structure of the service worker and focuses on the vulnerabilities of its components. After the literature analysis and some testing using the demonstrator developed during this project, the vulnerabilities of the service worker components are classified and presented in the form of the vulnerability matrix; the mitigations to the vulnerabilities are then outlined, and the two are summarized in the form of security guidelines.

Este projeto de mestrado tem como objetivo principal construir Web services de modo a permitir a avaliação de desempenho de uma arquitetura denominada WSARCH. A arquitetura WSARCH foi proposta de modo a prover uma infra-estrutura de Web services considerando aspectos de qualidade de serviço (QoS). Este projeto contribui diretamente com o desenvolvimento desta arquitetura, além de auxiliar na sua validação e na realização de estudos de desempenho de suas funcionalidades. Trabalhos preliminares de pesquisa foram desenvolvidos de forma que, além de auxiliar no desenvolvimento da WSARCH, também contribuíram em pesquisas relacionadas com a área de Web services. Destacam-se estudos realizados com anexos em Web services (WS-Attachments) e estudos com operações de pesquisa e publicação em repositórios UDDI. Por fim, foram realizados estudos de avaliação de desempenho com diferentes tipos de aplicação implantados em provedores que compõem a arquitetura WSARCH
This masters degree project has as main objective to build Web services to evaluate the performance of the WSARCH architecture. The WSARCH architecture was proposed aiming at providing Web services infrastructure implementation considering quality of services aspects. This project contributed directly with the development of this architecture, in addition to helping in validation and performance studies of WSARCHs features. Preliminary research work have been developed in order to contribute in research related to Web services besides helping in the development of WSARCH. Among them there are studies of attachments in Web services (WS-Attachments) and studies in research and publishing operations in UDDI repositories. Finally, studies of performance evaluation with different types of applications deployed on service providers that compose the architecture WSARCH

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Web mapping systems, or Web GIS, are important tools for geographic orientation and spatial data analysis. In recent years, the use of these systems has increased, as well as the challenge to ensure performance while the number of users and the data volume continue to grow. The performance evaluation is an important activity to investigate and mitigate systems performance issues. The workload is the starting point of the performance evaluation and is responsible for sending resquests to the system under evaluation. The reliability of the evaluation results is related to an appropriate load. Despite the importance of web map systems, the literature as presented little efforts to model the workload of these systems. In this dissertation, we present a methodology to collect and analyze data in order to create a model of Web GIS users’ behavior and to instantiate the model in a workload generator. We also propose a generic model, named MUSe-GM (Maps User Session Generative Model), and present a characterization of the users’ behavior using data of the access to a popular mapping application, collected by an extension developed for the Google Chrome browser. The characterization results were used to develop an instance of the behavior model and to implement a workload generator. The instance was evaluated by testing in a realWeb map system, using the workload generator, and through simulations. The results were compared with two other models from literature. The proposed model in this dissertation was significantly different in several aspects compared to the other, presenting a behavior closer to the real users’ behavior.
Sistemas de mapa Web, ou SIGs Web, são ferramentas importantes para orientação geográfica e análise de dados espaciais. Nos últimos anos, o uso desse tipo de sistema tem aumentado, bem como o desafio para garantir o desempenho frente ao aumento do número de usuários e do volume de dados. A avaliação de desempenho é uma importante atividade para investigar e mitigar problemas de desempenho em sistemas. O ponto inicial da avaliação de desempenho é a carga de trabalho, responsável por enviar requisições ao sistema sob avaliação. A confiabilidade dos resultados da avaliação depende de uma carga adequada. Apesar da importância dos sistemas de mapa Web, existem poucos esforços na literatura para modelar a carga de trabalho desse tipo de sistema. Nesta dissertação, apresentamos uma metodologia para coleta e análise de dados, visando a criação de um modelo do comportamento dos usuários de SIGs Web e sua instanciação em um gerador de cargas de trabalho. Propomos também um modelo genérico, chamado MUSe- GM (Maps User Session Generative Model), e apresentamos uma caracterização do comportamento dos usuários utilizando dados de acesso a um sistema de mapas popular, coletados a partir de uma extensão desenvolvida para o navegador Google Chrome. Os resultados da caracterização foram utilizados para a criação de uma instância do modelo de comportamento e na implementação de um gerador de cargas. A instância foi avaliada através de testes em um sistema de mapas real, utilizando o gerador de cargas, e por meio de simulações. Os resultados foram comparados aos de outros dois modelos da literatura. O modelo proposto nesta dissertação se mostrou significativamente diferente em vários aspectos em relação aos outros dois, apresentando um comportamento mais próximo do comportamento de usuários reais.

Over the last years, online learning has gained significant popularity, and this trend is expected to continue in the future. Online learning is a multi-dimensional activity where each dimension should be adequately supported by an online learning system to provide a fruitful learning experience to its users.

Similar to online learning, a particular approach in the way systems are designed has gained increasing popularity over the last years as a result of the emergence of the computer network. Systems have started to be envisioned as integrated collections of components that are deployed over the network. This network-centric approach addresses some of the issues that are not directly addressed by the traditional architectural design approaches. We believe that such an approach can be employed for the architectural design of online learning environments (OLEs) where different dimensions of online learning are addressed by different components residing on the network.

This thesis presents a network-centric system architecture for OLEs. The architecture is based on the Service-Oriented Architecture (SOA) paradigm and web services. The proposed architecture is described using a number of Department of Defense Architecture Framework (DoDAF) representations. We also developed a quality model for OLEs and evaluated the architecture using this quality model.

We believe that this research is an important first step in reconciling those two emerging ideas, namely online learning and network-centric architecture. This reconciliation is important as the flexible nature of SOA can be very useful in creating OLEs that address a wide variety of user needs.
Master of Science

Esta tese de doutorado tem como objetivo principal, a proposta de um sistema onde é possível avaliar abordagens diferentes para composição automática de Web services, baseando-se em parâmetros de QoS que dependem da execução para serem medidos. O objetivo foi atingido por meio da implementação de um sistema denominado AWSCS (Automatic Web Service Composition System). O AWSCS é um sistema onde é possível implementar abordagens diferentes para composição automática de Web services e também executar os fluxos resultantes dessas abordagens. Com o objetivo de demonstrar os resultados desta tese de doutorado, foram elaborados cenários, onde fluxos empíricos foram construídos para fazer a demonstração do funcionamento do AWSCS, uma vez que algoritmos para composição automática não foram encontrados para download na literatura. Com os resultados foi possível fazer um estudo do comportamento da execução de fluxos de Web services compostos, quando fluxos com mesma funcionalidade, mas estratégias de solução do problema diferentes foram comparados. Além disso, foi possível observar a influência das cargas aplicadas no sistema em execução, uma vez que o tipo de carga submetida ao sistema é um fator importante para se definir qual abordagem para composição de Web services pode levar ao melhor desempenho, de acordo com o ambiente e tipos de cargas que ele vai receber, quando em produção.
This PhD thesis has as main goal the propose of a system where it is possible to evaluate different approaches for automatic composition ofWeb services, based on QoS parameters that depend on the execution to be measured. The goal was reached by means of the implementation of a system named AWSCS (Automatic Web Service Composition System). The AWSCS is a system where it is possible to implement different approaches for automatic composition of Web services and also to execute the resulting flows from these approaches. Aiming at demonstrating the results of this PhD thesis different scenarios were developed, where empirical flows were built to demonstrate the operation of AWSCS, once algorithms for automatic composition were not found to download in the literature,. With the results it was possible to study the behavior of running composite Web services, when flows with the same functionality but different problem-solving strategies were compared. Furthermore it was possible to observe the influence of the load applied on the running system once the type of load submitted to the system is an important factor to define which approach for the Web service composition can take to the best performance according to the environment and types of load it will receive when in production.

This thesis proposes a collaboration framework for the Web of Things based on the concepts of Service-oriented Architecture and integrated with semantic web technologies to offer new possibilities in terms of efficient asset management during operations requiring multi-actor collaboration. The motivation for the project comes from the rise in disasters where effective cross-organisation collaboration can increase the efficiency of critical information dissemination. Organisational boundaries of participants as well as their IT capability and trust issues hinders the deployment of a multi-party collaboration framework, thereby preventing timely dissemination of critical data. In order to tackle some of these issues, this thesis proposes a new collaboration framework consisting of a resource-based data model, resource-oriented access control mechanism and semantic technologies utilising the Semantic Sensor Network Ontology that can be used simultaneously by multiple actors without impacting each other’s networks and thus increase the efficiency of disaster management and relief operations. The generic design of the framework enables future extensions, thus enabling its exploitation across many application domains. The performance of the framework is evaluated in two areas: the capability of the access control mechanism to scale with increasing number of devices, and the capability of the semantic annotation process to increase in efficiency as more information is provided. The results demonstrate that the proposed framework is fit for purpose.

Electronic government (e-Government) in terms of public service delivery and administration has endured signification transformation over the last decade. More recently, modern second generation web technologies (Web 2.0) have started to be used to deliver e-Government. However, this in turn has brought about additional challenges. By its nature, Web 2.0 is more interactive than the traditional model of information provision or creation of digital services and as such opens up a new set of benefits, costs and risks to those who make use of it as part of their e-Government approach. In the main, the usage of Web 2.0 is in its infancy within e-Government and this creates a need for research into exploring the application of Web 2.0 technologies in e-Government and to provide practical advice to practitioners. This research draws on the existing literature to present a novel conceptual model that could be used to guide implementation and evaluation of Web 2.0. The conceptual model draws the existing literature into the traditional information systems (IS) evaluation model (benefits, costs and risks) specifically in terms appropriate to Web 2.0. In turn that evaluation is set in the context of the impact on the organisation in terms of organisational, technological and social consequences. This conceptual model was tested in a United Kingdom local government authority (LGA) that had recently started to make use of Web 2.0 in terms of service delivery and for internal work purposes by its employees. The result was a qualitative enquiry making use of interviews and documentary evidence to explore the validity of the conceptual model as a tool to assist decision making in this field. The findings elicited from the in-depth case study offer an insight into IS evaluation criteria and impact factors of Web 2.0 from both a practical setting and an internal organisational perspective. An interesting finding of this study was the contrast between the agreement on the need for evaluation of Web 2.0 tools and how to carry that out, and the fact that this had not been formally carried out by the case study with respect to its early Web 2.0 projects. This study concludes that a combined analysis of the evaluation and impact factors rather than a singular approach would better assist the decision making process that leads to effective application of Web 2.0 technologies. Keywords: e-Government, Web 2.0, Information Systems Evaluation, Impact, Local Government Authorities (LGAs).

Master’s thesis deals with implementation of a European standard DATEX II. This standard specifies the data format for information transmission in road transport. The road traffic is flowing streams of current information. For the work was selected network of meteorological stations, which will publish the measured data, ie weather conditions of road transport. Measured data will be available to consumers in the format DATEX II. Implementation will be operational in its entirety meteorological station from design to the actual web service that will produce data information for consumers.

碩士
國立中正大學
會計與資訊科技研究所
97
With the development of Internet and prevalence of e-commerce,market mechanism has turned into customer-oriented from seller-oriented.In order to increase sales volume,online store assure Internet trust to user by seal assurance service. AICPA in America post assurance service in e-commerce to extend the CPA service area by providing assurance service seal from accountants. However, there are differences in seal recognition between user and seal provider.Thus,the thesis which refer assurance gap model posted by Burke,Kovar,and Prenshaw discuss further the effect between users’ seal service recognition and seal providers’ seal service recognition to the level of web trust.Through the way of questionnaire survey, the reaserch summarise empirically as follow: 1. Prepurchase expectations of CPA provider is larger than prepurchase expectations of user, so it affect seal service satisfaction. 2. Prepurchase expectations of CPA provider is larger than prepurchase expectations of user, so it affect seal service satisfaction. 3. The satisfaction of seal service provider is positively related with web trust belief and web trust intention, and the satisfaction of user is positively related with web trust belief and web trust intention, too. So they show seal service can affect web trust on user and provider. 4. Seal assurance service on CPA can increase the value of core trust on third-party provider, and reach the purpose of increasing level of web trust. To sum up, the result offer accounting firm in Taiwan a reference to development of seal assurance service in order to expand their service market.