A branch and bound and simulated annealing approach for job shop scheduling

This paper presents two approaches to the solution of the job shop scheduling problem, namely the branch and bound, and simulated annealing approach. The objective is to schedule the jobs on the machines so that the total completion time is minimized. In the branch and bound approach, the job shop scheduling problem is represented by a disjunctive graph, then the optimal schedule is obtained using the branch and bound algorithm while simulated annealing is a local search based algorithm which will slightly perturb the initial feasible solution to decrease the makespan

Faster Convex Optimization: Simulated Annealing with an Efficient Universal Barrier

This paper explores a surprising equivalence between two seemingly-distinct convex optimization methods. We show that simulated annealing, a well-studied random walk algorithms, is directly equivalent, in a certain sense, to the central path interior point algorithm for the the entropic universal barrier function. This connection exhibits several benefits. First, we are able improve the state of the art time complexity for convex optimization under the membership oracle model. We improve the analysis of the randomized algorithm of Kalai and Vempala by utilizing tools developed by Nesterov and Nemirovskii that underly the central path following interior point algorithm. We are able to tighten the temperature schedule for simulated annealing which gives an improved running time, reducing by square root of the dimension in certain instances. Second, we get an efficient randomized interior point method with an efficiently computable universal barrier for any convex set described by a membership oracle. Previously, efficiently computable barriers were known only for particular convex sets

Investigation of Shallow Sedimentary Structure of the Anchorage Basin, Alaska, Using Simulated Annealing Inversion of Site Response

This study deals with shallow sedimentary structure of the Anchorage basin in Alaska. For this purpose, inversion of site response [SR(f)] data in the frequency range 0.5-11.0 Hz from various sites of the basin has been performed using the simulated annealing method to compute subsurface layer thickness, shear-wave velocity (beta), density, and shear-wave quality factor. The one-dimensional (1D) models for the aforementioned parameters were obtained with preset bounds on the basis of available geological information such that the L-2 norm error between the observed and computed site response attained a global minimum. Next, the spatial distribution of the important parameter beta was obtained by interpolating values yielded by the 1D models. The results indicate the presence of three distinct velocity zones as the source of spatial variation of SR(f) in the Anchorage basin. In the uppermost part of the basin, the beta values of fine-grain Quaternary sediments mainly lie in the range of 180-500 m/sec with thickness varying from 15 to 50 m. This formation overlies relatively thick (80-200 m) coarse-grain Quaternary sediments with beta values in the range of 600-900 m/sec. These two Quaternary units are, in turn, overlain on Tertiary sediments with beta > 1000 m/sec located at depths of 100 and 250 m, respectively, in the central and western side along the Knik Arm parts of the basin. The important implication of the result is that the sources of spatial variation of SR(f) in the Anchorage basin for the frequency band 0.5-11 Hz, besides in the uppermost 30 m, are found to be deeper than this depth. Thus, use of commonly considered geological formations in the depth intervals from 0 to 30 m for the ground-motion interpretation will likely yield erroneous results in the Anchorage basin.GIEnvironment and Natural Resources InstituteSchool of Engineering of the University of Alaska, AnchorageGeological Science

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Optimizing mating schemes in fish breeding

The optimal contribution selection method and the simulated annealing algorithm were used to maximize the genetic gain and reduce inbreeding in fish breeding populations. This study considered the following mating designs: full factorial (3 x 3); full factorial (6 x 6) and nested (6 males x 18 females). A quantitative trait based on a strictly additive and polygenic model was simulated. Two levels for the number of genotyped offspring (360 or 720) and three levels of heritability (0.1; 0.3; 0.5) were assumed. The best results in terms of DF and DG were obtained with the full factorial design (6 x 6) and considering a trait with a high heritability. The optimal family size was found at 20 fish per mating

Trace generator for opportunistic networks routing protocols through heuristic techniques

This report is concerning about the execution of the project to build an algorithm capable of generatingThe ONE simulator Scenarios in order to test delay tolerant networks (DTN) algorithms, specifically opportunistic networks, as well as the methodology employed to carry it out, special mention to the Simulated Annealing technique, which will be the key to the impartial The ONE simulator Scenarios Generator. However, it is also explained what kind of Scenario is going to be built. Furthermore, the report will show the state of the art, specifying other methods to obtain these Scenarios, such as by getting prebuild derived from human mobility ones or real-based ones. Moreover, the report will include the planning of the project, updates on the development of the project, including the explanation of the structure of the code and a guide to use it, and whether it has followed the planfication or not and why. Finally it will include the sources consulted in addition to some acknowledgments.Aquest informe tracta sobre l'execució d'un projecte que construeixi un algorisme capaç de generar Scenarios pel simulador The One, per poder testejar protocols d'encaminament per xarxes tolerants a retards (DTN), específicament per xarxes oportunístiques, a més de la metodologia per dur-ho a terme, mencionant de manera especial la tècnica del recuit simulat, que serà clau pel Generador d'Scenarios imparcials pel simulador The ONE. No obstant, també s'explica quina mena d'Scenario es construirà. A més, l'informe mostrarà l'estat de l'art, especificant altres mètodes per obtenir aquests Scenarios, com per exemple el que obté Scenarios pre-construïts derivats de la mobilitat humana o els basats en la realitat. En afegit, l'informe inclourà la planificació del projecte, les actualitzacions en el desenvolupament del projecte, incloent l'explicació de l'estructura del codi i una guia de com fer-lo servir, i si s'ha seguit o no la planificació establerta i el perquè. Finalment inclourà un llistat de les font consultades a més d'uns agraïments.Este informe trata sobre la ejecución de un proyecto que construye un algoritmo capaz de generar Scenarios para el simulador The ONE, para poder testear algoritmos de enrutamiento para redes tolerantes a retrasos (DTN), específicamente para redes oportunistas, además de la metodología para llevarlo a cabo, mencionando de manera especial la técnica del recocido simulado, que será clave para el Generador de Scenarios imparciales para el simulador The ONE. Sin embargo, también se explica que tipo de Scenario se construirá. Además, el informe mostrará el estado del arte, especificando otros métodos para obtener estos Scenarios, como por ejemplo el que obtiene Scenarios preconstruidos derivados de la movilidad humana o los basados en la realidad. Por otro lado, el informe incluirá la planificación del proyecto, las actualizaciones en su desarrollo, incluyendo la explicación de la estructura del código y una guía de como usarlo, y si se ha seguido o no la planificación establecida y el porqué. Finalmente incluirá una lista de las fuentes consultadas además de unos agradecimientos

Optimizing the location of weather monitoring stations using estimation uncertainty

In this article, we address the problem of planning a network of weather monitoring stations observing average air temperature (AAT). Assuming the network planning scenario as a location problem, an optimization model and an operative methodology are proposed. The model uses the geostatistical uncertainty of estimation and the indicator formalism to consider in the location process a variable demand surface, depending on the spatial arrangement of the stations. This surface is also used to express a spatial representativeness value for each element in the network. It is then possible to locate such a network using optimization techniques, such as the used methods of simulated annealing (SA) and construction heuristics. This new approach was applied in the optimization of the Portuguese network of weather stations monitoring the AAT variable. In this case study, scenarios of reduction in the number of stations were generated and analysed: the uncertainty of estimation was computed, interpreted and applied to model the varying demand surface that is used in the optimization process. Along with the determination of spatial representativeness value of individual stations, SA was used to detect redundancies on the existing network and establish the base for its expansion. Using a greedy algorithm, a new network for monitoring average temperature in the selected study area is proposed and its effectiveness is compared with the current distribution of stations. For this proposed network distribution maps of the uncertainty of estimation and the temperature distribution were created. Copyright (c) 2011 Royal Meteorological Societyinfo:eu-repo/semantics/publishedVersio