QoS-Aware Middleware for Web Services Composition

The paradigmatic shift from a Web of manual interactions to a Web of programmatic interactions driven by Web services is creating unprecedented opportunities for the formation of online Business-to-Business (B2B) collaborations. In particular, the creation of value-added services by composition of existing ones is gaining a significant momentum. Since many available Web services provide overlapping or identical functionality, albeit with different Quality of Service (QoS), a choice needs to be made to determine which services are to participate in a given composite service. This paper presents a middleware platform which addresses the issue of selecting Web services for the purpose of their composition in a way that maximizes user satisfaction expressed as utility functions over QoS attributes, while satisfying the constraints set by the user and by the structure of the composite service. Two selection approaches are described and compared: one based on local (task-level) selection of services and the other based on global allocation of tasks to services using integer programming

Experimental Performance Evaluation of Cloud-Based Analytics-as-a-Service

An increasing number of Analytics-as-a-Service solutions has recently seen the light, in the landscape of cloud-based services. These services allow flexible composition of compute and storage components, that create powerful data ingestion and processing pipelines. This work is a first attempt at an experimental evaluation of analytic application performance executed using a wide range of storage service configurations. We present an intuitive notion of data locality, that we use as a proxy to rank different service compositions in terms of expected performance. Through an empirical analysis, we dissect the performance achieved by analytic workloads and unveil problems due to the impedance mismatch that arise in some configurations. Our work paves the way to a better understanding of modern cloud-based analytic services and their performance, both for its end-users and their providers.Comment: Longer version of the paper in Submission at IEEE CLOUD'1

Constructing secure service compositions with patterns

In service based applications, it is often necessary to construct compositions of services in order to provide required functionality in cases where this is not possible through the use of a single service. Whilst creating service compositions, it is necessary to ensure not only that the functionality required of the composition is achieved but also that certain security properties are preserved. In this paper, we describe an approach to constructing secure service compositions. Our approach is based on the use of composition patterns and rules that determine the security properties that should be preserved by the individual services that constitute a composition in order to ensure that security properties of the overall composition are also satisfied. Our approach extends a framework developed to support the runtime service discovery

An Overview and Examination of the Indian Services Sector

India’s service sector has grown rapidly since the 1990s. Domestic demand for services has increased as incomes have risen, triggering the expansion of industries such as banking, education, and telecommunications. Exports have also increased rapidly, led by information technology and business process outsourcing (IT-BPO). India’s ability to offer low-cost, high-quality IT-BPO services has made it a world leader in this industry. However, employment in services has not grown as quickly as output. The majority of India’s jobseekers are low-skilled, but demand for workers is growing fastest in higher-skill industries. The supply of highly-skilled workers has not kept pace with demand, causing wages to increase faster for these workers than for lower-skilled ones. India’s government has supported the growth of service industries through a mix of deregulation, liberalization, and incentive programs, such as the Software Technology Parks of India. Nevertheless, burdensome regulations, poor infrastructure, and foreign investment restrictions continue to affect service firms’ ability to do business. USITC analysis suggests that additional liberalization would lead to an increase in India’s imports of services

Sizing Up Information and Communication Technologies as Agents of political Pevelopment in Sub-Saharan Africa

It is widely speculated that the emergence of modern information and communication technologies (ICTs) will boost political development in the developing world. This expectation anchors on solid foundation since, presumably, the ICT revolution would radically alter access to information, dislodge entrenched social cleavages, and unleash new patterns of citizen consciousness and civic engagement by hitherto marginalized mass publics, and orchestrate new and decisive political equilibriums. In this research, we provide an empirical assessment of the impact of ICTs on political development in sub-Saharan Africa. Our analysis suggests that speculation about the potential for ICTS to enhance political development in the sub-Sahara is not unrealistic. The levels of phone, computer, and internet diffusion are associated with political development, although only the effect of the phone remains once other variables are specified. The phone is the most robust of all individual factors explaining variations in political development. However, t he effect of ICTs on political development can neither be certified as revolutionary, nor can they be codified as panacea

Leveraging the Grid to Provide a Global Platform for Ubiquitous Computing Research

The requirement for distributed systems support for Ubicomp has led to the development of numerous platforms, each addressing a subset of the overall requirements of ubiquitous systems. In contrast, many other scientific disciplines have embraced the vision of a global distributed computing platform, i.e. the Grid. We believe that the Grid has the potential to evolve into an ideal platform for building ubiquitous computing applications. In this paper we explore in detail the areas of synergy between Grid computing and ubiquitous computing and highlight a series of research challenges in this space

Engineering Multimedia-Aware Personalized Ubiquitous Services

Ubiquitous computing focusing on users and tasks instead of devices and singular applications is an attractive vision for the future. Especially the idea of nomadic, mobile users poses new challenges on hardware and software. Mobile devices provide vastly different presentation capabilities and need to integrate into heterogeneous environments. Network bandwidth is far from being constant and services may be available only when online. This paper presents MUNDO, an infrastructure for ubiquitous computing that addresses these challenges. The infrastructure is intended to be non-monolithic with its parts supporting mobile computing using multi-modal user interfaces, mobile data delivery, and ad-hoc communication and networking

Testing for sexually transmitted infections in the general population of the Rotterdam area:Who goes where?

The research described in this thesis aims to improve our understanding of sexually transmitted infection (STI) testing in the general population, focusing on the roles of general practitioners and sexual health centres. The study insights may contribute to improved STI testing policies

Testing for sexually transmitted infections in the general population of the Rotterdam area:Who goes where?

The research described in this thesis aims to improve our understanding of sexually transmitted infection (STI) testing in the general population, focusing on the roles of general practitioners and sexual health centres. The study insights may contribute to improved STI testing policies