In dynamic service-oriented environment, service monitoring could provide reliability improvement to service composition as well as cost increase. To reduce the overall cost brought by monitoring, existing literatures proposed to decrease the number of monitors through monitoring the most reliability-sensitive services. However, the optimal monitoring rate for those monitors was not taken into ...

This paper investigates a queueing system in which the controller can perform admission and service rate control. In particular, we examine a single server queueing system with Poisson arrivals and exponentially distributed services with adjustable rates. At each decision epoch the controller may adjust the service rate. Also, the controller can reject incoming customers as they arrive. The obj...

OBJECTIVE The objective of this study was to compare reproductive performance parameters for two protocols for estrus synchronization in dairy heifers in Germany. MATERIAL AND METHODS In the CIDR group (n=93) all heifers received a controlled intravaginal progesterone releasing insert (Eazi-Breed™ CIDR®; Pfizer Pharma GmbH; containing 1,38g of progesterone) on day 0. On day 7 these cows were ...

We consider a single-server queue with Poisson arrivals, where holding costs are continuously incurred as a non-decreasing function of the queue length. The queue length evolves as a birth-and-death process with constant arrival rate λ = 1 and with state-dependent service rates μn that can be chosen from a fixed subset A of [0,∞). Finally, there is a non-decreasing cost-of-effort function c(·) ...

In this paper we study a queueing model with a server that changes its service rate according to a nite birth and death process. The object of interest is the simultaneous distribution of the number of customers in the system and the state of the server in steady-state. The model can be applied to the performance analysis of (low priority) Available Bit Rate (ABR) tra c at an ATM switch in the ...

Recently, Service Discovery protocols in MANET have gained special attention from the research centers. In existing method, Service discovery protocols in mobile networks does not guarantee load balancing on routing paths between service providers and service requesters. It does not guarantee the performance attributes to service requesters and service providers. It permit to satisfy some perfo...

We consider a class of general Gt/Gt/1 single-server queues, including the Mt/Mt/1 queue, with unlimited waiting space, service in order of arrival and a time-varying arrival rate, where the the service rate at each time is subject to control. We study the rate-matching control, where the the service rate is made proportional to the arrival rate. We show that the model with the rate-matching co...

The problem of access and service rate control as a general optimization problem for controlled Markov process with finite state space is considered. By using the dynamic programming approach we obtain the explicit form of the optimal control in the case of minimizing cost given as a mixture of an average queue length, number of lost jobs, and service resources. The problem is considered on a f...

The tra c generated by multimedia applications presents a high degree of burstiness that can hardly be described by a static set of tra c parameters. We present a dynamic QoS negotiation scheme applied to a prototype application that provides temporized data transfer. The dynamic and e cient usage of the resources can be reached with the introduction of the renegotiable variable bit rate (RVBR)...