Search results for " Program"

A Group-Based Protocol for Large Wireless AD-HOC and Sensor Networks

2008

Many routing protocols for ad-hoc networks and sensor networks have been designed, but none of them is based on groups. It is known that grouping nodes gives better performance to the group and to the whole system, thereby avoiding unnecessary message forwarding and additional overheads. We propose an approach where the network is split into several groups of sensors where connections between groups are established as a function of the proximity and the neighbor's available capacity (based on the sensor's energy). In this paper the network architecture is described with its mathematical description and the messages that are needed to proper operation. It is also simulated how much time is n…

Alma Mater: 2014/ Pavasaris

2014

Andra Čudare. Studentu students Rūta Mājeniece -- Studiju prakse - piedzīvo grāmatās rakstīto -- Lauma Abramoviča. Inta Brūna: cilvēks var padarīt ļoti daudz, ja vēlas -- LU Preses centrs. Prezentē jaunās Zobārstniecības mācību klīnikas telpas un programmu -- LU Preses centrs. Latvijas Universitāte Eiropas kultūras kontekstā -- Katrīna Žukova. LU dienesta romāni un mīlas stāsti -- Grācija Tafuni. Nevīžība un precizitāte: vienas medaļas divas puses -- Santa Margēviča. Klase aizraujošām mācībām -- LU Preses centrs. Pasniegtas ikgadējās Latvijas Universitātes Gada balvas -- Kristaps Gustsons. Latvijas Universitātes studente Soču olimpiskajās spēlēs -- Laine Dobulāne. LU Fonda stipendijas – amb…

Design Considerations of Transverse Flux Generator to Sea Wave Energy

2014

In this paper we study the possibility to use a transverse flux linear generator (TFG) because transverse flux technology presents the highest force density per volume index among the iron based electrical machines. This paper is organized as follows an introduction to describe "state of the art" of WEC's and TFG, in the Section II we find a summary description of the marine condition of the chosen site; in the Section III there is an the analytical procedure for geometric and magnetic design of device (chosen material, length, etc) and in the Section IV the simulation of generator. Further defined the design of the generator, the machine was designed and analyzed through the use of a 3D FE…

A combined approach of SGBEM and conic quadratic optimization for limit analysis

2011

The static approach to evaluate the limit multiplier directly was rephrased using the Symmetric Galerkin Boundary Element Method (SGBEM) for multidomain type problems [1,2]. The present formulation couples SGBEM multidomain procedure with nonlinear optimization techniques, making use of the self-equilibrium stress equation [3-5]. This equation connects the stresses at the Gauss points of each substructure (bem-e) to plastic strains through a self-stress matrix computed in all the bem-elements of the discretized system. The analysis was performed by means of a conic quadratic optimization problem, in terms of discrete variables, and implemented using Karnak.sGbem code [6] coupled with MathLa…

The HITRAN2016 molecular spectroscopic database

2017

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of …

SURVEILLANCE PROGRAM FOR DIAGNOSIS OF HCC IN LIVER CIRRHOSIS: ROLE OF ULTRASOUND ECHOPATTERNS

2013

The mapping properties of the radiosity operator along an edge

2002

In this article we study the radiosity operator along an edge between two adjacent half-planes. First we show that the radiosity operator is invertible in a whole scale of anisotropic Sobolev spaces. In the absence of any shadows we are able to derive regularity properties of the solution, which depend only on the angle between the half-planes, the reflectivity coefficients and the right-hand side. This work can be considered as a supplement to the article of Rathsfeld (Mathematical Methods in the Applied Sciences 1999; 22: 217–241). Copyright © 2002 John Wiley & Sons, Ltd.

Checkpointing Workflows for Fail-Stop Errors

2017

International audience; We consider the problem of orchestrating the exe- cution of workflow applications structured as Directed Acyclic Graphs (DAGs) on parallel computing platforms that are subject to fail-stop failures. The objective is to minimize expected overall execution time, or makespan. A solution to this problem consists of a schedule of the workflow tasks on the available processors and of a decision of which application data to checkpoint to stable storage, so as to mitigate the impact of processor failures. For general DAGs this problem is hopelessly intractable. In fact, given a solution, computing its expected makespan is still a difficult problem. To address this challenge,…

Flexibility Services to Minimize the Electricity Production from Fossil Fuels. A Case Study in a Mediterranean Small Island

2019

The design of multi-carrier energy systems (MESs) has become increasingly important in the last decades, due to the need to move towards more efficient, flexible, and reliable power systems. In a MES, electricity, heating, cooling, water, and other resources interact at various levels, in order to get optimized operation. The aim of this study is to identify the optimal combination of components, their optimal sizes, and operating schedule allowing minimizing the annual cost for meeting the energy demand of Pantelleria, a Mediterranean island. Starting from the existing energy system (comprising diesel generators, desalination plant, freshwater storage, heat pumps, and domestic hot water st…

Pre-emption in resource-constrained project scheduling

2008

Abstract The Resource-Constrained Project Scheduling Project (RCPSP), together with some of its extensions, has been widely studied. A fundamental assumption in this basic problem is that activities in progress are non-preemptable. Very little effort has been made to uncover the potential benefits of discrete activity pre-emption, and the papers dealing with this issue have reached the conclusion that it has little effect on project length when constant resource availability levels are defined. In this paper we show how three basic elements of many heuristics for the RCPSP – codification, serial SGS and double justification – can be adapted to deal with interruption. The paper is mainly foc…