The M/M/s queueing model assumes arrival rates, service rates, and number of servers to be constant in time. It is straightforward to extend the model to allow a time-varying arrival rate and a time-varying service rate, and the resulting models can be solved numerically using standard solvers for ordinary differential equations. The extension to a time-varying number of servers requires consid...

In this paper, we present a framework that we have developed to support the monitoring of service level agreements. The agreements that can be monitored by this framework are expressed in an extension of WS-Agreement that we propose. The main characteristic of the proposed extension is that it uses an event calculus based language, called EC-Assertion, for the specification of the service guara...

We study the correct interaction between services using the following notion for correctness: there is no deadlock in the interaction of the services, and a given set of activities is not dead, that is, each activity in this set is executed in at least one run. The second condition has not been studied before. An operating guideline of a service P is an operational characterization of all deadl...

Web service technologies are best exploited by composing services, and BPEL (Web Services Business Process Execution Language) is adopted industrial-wide as the de facto service composition standard. However, a BPEL composite service is typically treated as a fully automated service flow that orchestrates multiple web services and involves no user interactions – a desirable feature for service ...

The proliferation of mobile computing devices over the past decade has expedited researches on mobility services and architecture, namely, Mobile IP, Mobile QoS and multimedia content adaptation for limited wireless bandwidth. However, to our knowledge, all of the currently proposed mobility service architectures, such as [3], [7], are restricted to operate within one administrative domain, or ...

Today’s database management systems are mainly large and heavy-weight monoliths that, even worse, undergo steady extensions in functionality. This makes them highly complex and creates problems when it comes to build tailored extensions. Our goal is to introduce more flexibility and extensibility by founding our database architecture on the principles of Service Oriented Architecture (SOA). In ...

Extension is a partnership between government, landowners and communities, providing planned care education to meet community needs. The purpose of service increase the ability extension workers in technique jajar legowo rice cultivation. training method presentation material practice. results show an planting rice.

An important class of location-based services answers the question, "What instances of this service are closest to me?" Examples include finding restaurants, gas stations, stores, automated teller machines, wireless access points (hot spots), or parking spaces. Currently, the Location-to-Service Translation (LoST) protocol only supports mapping locations to a single service based on service reg...

We present an extension of the window flow control analysis by R. Agrawal et. al. (Reference [1]), C.-S. Chang (Reference [6]), and C.-S. Chang et. al. (Reference [8]) to a system with random service time and fixed feedback delay. We consider two network service models. In the first model, the network service process itself has no time correlations. The second model addresses a two-state Markov...

Service-Oriented Computing and agent technology are nowadays two of the most active research areas in distributed and open systems. Given the growing interest in bridging the two worlds, in this paper we describe a novel approach for service description, discovery and composition in multiagent systems, based on organizational models. An extension to service matching techniques will be presented...