Search results for " Programming"
showing 10 items of 1616 documents
Mobile agents and grid computing
2004
Publisher Summary This chapter describes mobile agents as an effective solution for grid service provision. A short overview is first introduced on the grid paradigm and the most known research activities in the field. Then, mobile agents are discussed and a comparison with the remote procedure call (RPC) method is made as far as the most effective solution to minimize network overload and fault occurrences is concerned. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. Community members agree on a set of sharing rules and permissions, by which resources to be shared and membe…
Improvement of a Service Level Negotiation Protocol using Formal Verification
2013
International audience; The goal of the pervasive connectivity is to enable mobile users to be permanently connected to the Internet. Mobile users are often connected to wireless networks and consuming services that require quality of service guarantees. Accessing services using wireless technologies may make the service delivery vulnerable to security attacks because of the open medium of these technologies. In this context, we need to guarantee both quality of service and security for mobile users communications. In this paper, we present a protocol for service level negotiation which covers both quality of service and security and assigns a profile to each user in order to optimize and a…
Does service quality matter in measuring the performance of water utilities?
2008
Abstract Quality is a dimension of water services that has been repeatedly omitted in the study of performance of water utilities. In this paper, Data Envelopment Analysis techniques are used to compute both conventional quantity-based and quality-adjusted scores of technical efficiency for a sample of Spanish water utilities. The key assumptions are that a lack of quality (bad quality) can be regarded as a bad output and the existence of a trade-off between quantity and quality. Our main results indicate that quality matters in measuring technical efficiency, the difference between conventional and quality-adjusted evaluations representing the opportunity cost of maintaining quality. Avera…
The Rail Quality Index as an Indicator of the “Global Comfort” in Optimizing Safety, Quality and Efficiency in Railway Rails
2012
AbstractThe proposed model uses the stochastic dynamic programming and in particular Markov decision processes applied to the Rail Quality Index (RQI - Italian Indice di Qualità del Binario, IQB).By performing the integrated analysis of the classes of variables which characterize the overall service quality (in terms of comfort and safety), the proposed mathematical approach allows to find the solutions to the decision-making process in function of the probability of deterioration of the state variables of the infrastructure over time and of the flow of available resources.
The OptQuest Callable Library
2005
In this chapter we discuss the development and application of a library of functions that is the optimization engine for the OptQuest system. OptQuest is commercial software designed for optimizing complex systems, such as those formulated as simulation models. OptQuest has been integrated with several simulation packages with the goal of adding optimization capabilities. The optimization technology within OptQuest is based on the metaheuristic framework known as scatter search. In addition to describing the functionality of the OptQuest Callable Library (OCL) with an illustrative example, we apply it to a set of unconstrained nonlinear optimization problems.
Manager's Toolbox for OSS/BSS Market Analysis
2009
The purpose of this section is to provide a set of quick tools for analysts and managers to analyze the status of the telecom operator software market.
Fast and Accurate Bounds on Linear Programs
2009
We present an algorithm that certifies the feasibility of a linear program while using rational arithmetic as little as possible. Our approach relies on computing a feasible solution of the linear program that is as far as possible from satisfying an inequality at equality. To realize such an approach, we have to detect the set of inequalities that can only be satisfied at equality. Compared to previous approaches for this problem our algorithm has a much higher rate of success.
Certifying feasibility and objective value of linear programs
2012
Abstract We present an algorithm that certifies the feasibility of a linear program and computes a safe bound on its objective value while using rational arithmetic as little as possible. Our approach relies on computing a feasible solution that is as far as possible from satisfying an inequality at equality. To this end, we have to detect the set of inequalities that can only be satisfied at equality. Compared to previous approaches, our algorithm has a much higher success rate.
Black-Box Solvers
2017
Linear programming is perhaps the best-known tool for optimization. Linear programming is a general-purpose framework that allows a real system to be abstracted as a model with a linear objective function subject to a set of linear constraints.
Left-to-right tree pattern matching
1991
We propose a new technique to construct left-to-right matching automata for trees. Our method is based on the novel concept of prefix unifcation which is used to compute a certain closure of the pattern set. From the closure a kind of deterministic matching automaton can be derived immediately. We also point out how to perform the construction incrementally which makes our approach suitable for applications in which pattern sets change dynamically, such as in the Knuth-Bendix completion algorithm.