Linear integer constraints are one of the most important constraints in combinatorial problems since they are commonly found in many practical applications. Typically, encoding linear constraints to SAT performs poorly in problems with these constraints in comparison to constraint programming (CP) or mixed integer programming (MIP) solvers. But some problems contain a mix of combinatoric constr...

Many-core architectures are a commercial reality, but programming them efficiently is still a challenge, especially if the mix is heterogeneous. Here granularity must be addressed, i.e. when to make use of concurrency resources and when not to. We have designed a data-driven, fine-grained concurrent execution model (SVP) that captures concurrency in a resource-agnostic way. Our approach separat...

In this paper we analyze the electricity portfolio problem of a big consumer in a multi-stage stochastic programming framework. Stochasticity enters the model via the uncertain spot price process and is represented by a scenario tree. The decision that has to be taken is how much energy should be bought in advance, and how large the exposition to the uncertain spot market, as well as the relati...

The appeal of constraint programming (CP) lies in compositionality – the ability to mix and match constraints as needed. However, this flexibility typically does not extend to the types of variables. Solvers usually support only a small set of pre-defined variable types, and extending this is not typically a simple exercise: not only must the solver engine be updated, but then the library of su...

background: the prevalence of allergic diseases has risen in the last decades. the objective of this study was to determine the common allergens in children via the skin prick test. methods: this cross-sectional study recruited 313 allergic children (4 months to 18 years old) referred to the asthma and allergy clinic of children’s medical center in tehran. a questionnaire containing demographic...

A STOCHASTIC PROGRAMMING APPROACH TO POWER PORTFOLIO OPTIMIZATION Suvrajeet Sen Lihua Yu Talat Genc Raptor Laboratory, SIE Department, University of Arizona, Tucson, AZ 85721,U.S.A. September 20,2004 We consider a power portfolio optimization model that is intended as a decision aid for scheduling and hedging (DASH) in the wholesale power market. Our multi-scale model integrates the unit commit...

In the well-known Vehicle Routing Problem (VRP) a set of identical vehicles located at a central depot is to be optimally routed to supply customers with known demands subject to vehicle capacity constraints. An important variant of the VRP arises when a mixed fleet of vehicles, characterized by different capacities and costs, is available for distribution activities. The problem is known as Fl...

This paper addresses the security and efficiency issues of the Mix-net based on permutation networks introduced in [1]. We first show that the original construction results in a Mix-net that yields biased permutation, so it gives some advantage to adversaries. A simple repair is provided. We then observe that one of the original schemes can be improved so that the servers and verifier enjoy mor...

We present the architecture, design issues and functions of a MIX-based system for anonymous and unobservable real-time Internet access. This system prevents tra c analysis as well as ooding attacks. The core technologies include an adaptive, anonymous, time/volumesliced channel mechanism and a ticket-based authentication mechanism. The system also provides an interface to inform anonymous user...

In this paper, the effect of super plasticizer amount, water/cement ratio, the cement, silica fume and steel micro fiber content is studied on the ultimate compressive strength of new generation of Ultra High Strength Concrete (UHSC).Known as Reactive Powder Concrete (RPC) and also have used two non-linear functions; Genetic Programming (GP) and Group Method of Data Handling (GMDH), which are t...