基于Web Services的移动通信综合网管系统

基于Web Services分布式原理，提出了一种新的移动通信综合网管系统的方案．该系统与目前国内传统的TMN网管系统相比，在匹配性、移植性、扩展性、安全性以及重用性等方面都具有明显的优越性．通过对Web Services体系结构分析研究，给出了Web Services到TMN网管系统的映射．并在试验环境中，实现和验证了这种基于Web Services分布式综合网管系统．最后对如何用，ETWeb服务来实现综合的网管的关键技术进行了阐述和分析。     

Recent optimization models and trends in location,relocation, and dispatching of emergency medical vehicles

Over the past 10 years, a considerable amount of research has been devoted to the development of models to support decision making in the particular yet important context of Emergency Medical Services (EMS). More specifically, the need for advanced strategies to take into account the uncertainty and dynamism inherent to EMS, as well as the pertinence of socially oriented objectives, such as equity, and patient medical outcomes, have brought new and exciting challenges to the field. In this context, this paper summarizes and discusses modern modeling approaches to address problems related to ambulance fleet management, particularly those related to vehicle location and relocation, as well as dispatching decisions. Although it reviews early works on static ambulance location problems, this review concentrates on recent approaches to address tactical and operational decisions, and the interaction between these two types of decisions. Finally, it concludes on the current state of the art and identifies promising research avenues in the field.     

Approximate dynamic programming for capacity allocation in the service industry

We consider a problem where different classes of customers can book different types of service in advance and the service company has to respond immediately to the booking request confirming or rejecting it. The objective of the service company is to maximize profit made of class-type specific revenues, refunds for cancellations or no-shows as well as cost of overtime. For the calculation of the latter, information on the underlying appointment schedule is required. In contrast to most models in the literature we assume that the service time of clients is stochastic and that clients might be unpunctual. Throughout the paper we will relate the problem to capacity allocation in radiology services. The problem is modeled as a continuous-time Markov decision process and solved using simulation-based approximate dynamic programming (ADP) combined with a discrete event simulation of the service period. We employ an adapted heuristic ADP algorithm from the literature and investigate on the benefits of applying ADP to this type of problem. First, we study a simplified problem with deterministic service times and punctual arrival of clients and compare the solution from the ADP algorithm to the optimal solution. We find that the heuristic ADP algorithm performs very well in terms of objective function value, solution time, and memory requirements. Second, we study the problem with stochastic service times and unpunctuality. It is then shown that the resulting policy constitutes a large improvement over an “optimal” policy that is deduced using restrictive, simplifying assumptions.     

Impact of sourcing flexibility on the outsourcing of services under demand uncertainty

This paper investigates the relationship between market conditions and the value and use of sourcing flexibility for service processes. We develop and analyze a series of models, and we derive expressions for the optimal switching decision, the value of the option to outsource, the value of the option to backsource, and the probability and timing of switches between the alternative sources.     

The inter-modes mixing effects in Mode Group Diversity Multiplexing

Multiplexing technology in indoor optical networks with multimode fibres allows the integration of several services to the end user. The Mode Group Diversity Multiplexing technique (MGDM) in Graded-Index Multi-Mode (GI-MMF) fibre makes the system less expensive with simpler transmitters and receivers, keeping the same information capacity as other multiplexing techniques. The capacity conservation and transmission quality obtained using MGDM technique depends on the transmission conditions and the state of fibre. Bending of the fibre can affect the system by changing modes excited for the different propagation channels in the fibre. In this paper an analytical modelling method for MGDM will be presented. Improvements in system sending and receiving conditions are studied. Modelling of the fibre curvature as well as the effects of coupling patterns on the MGDM are discussed.     

On comparing the performance of primary care providers

In the past few years primary health care has been characterised as central to the development of the National Health Service in the United Kingdom. Furthermore, performance assessment is seen as a way of achieving care of high standards. Performance indicators and targets are being developed to assess primary care providers, and to develop financial incentives. However, the number of studies that have compared the performance of primary care providers is limited and the existing approaches to evaluation are open to improvement.     

Optimal allocation of MRI scan capacity among competing hospital departments

We consider an MRI scanning facility run by a Radiology department. Several hospital departments compete for capacity and have private information regarding their demand for scans. The fairness of the capacity allocation by the Radiology department depends on the quality of the information provided by the hospital departments. We employ a generic Bayesian game approach that stimulates the disclosure of true demand (truth-telling), so that capacity can be allocated fairly. We derive conditions under which truth-telling is a Bayesian Nash equilibrium. The usefulness of the approach is illustrated with a numerical example.     

A location–allocation problem for a web services provider in a competitive market

Web Services have become a viable component technology in distributed e-commerce platforms. Due to the move to high-speed Internet communication and tremendous increases in computing power, network latency has begun to play a more important role in determining service response time. Hence, the locations of a Web Services provider’s facilities, customer allocation, and the number of servers at each facility have a significant impact on its performance and customer satisfaction. In this paper we introduce a location–allocation model for a Web Services provider in a duopoly competitive market. Demands for services of these servers are available at each node of a network, and a subset of nodes is to be chosen to locate one or more servers in each. The objective is to maximize the provider’s profit. The problem is formulated and analyzed. An exact solution approach is developed and the results of its efficiency are reported.