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## A holonic approach to dynamic manufacturing scheduling

Leitão, Paulo; Restivo, Francisco
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.04%
Manufacturing scheduling is a complex combinatorial problem, particularly in distributed and dynamic environments. This paper presents a holonic approach to manufacturing scheduling, where the scheduling functions are distributed by several entities, combining their calculation power and local optimization capability. In this scheduling and control approach, the objective is to achieve fast and dynamic re-scheduling using a scheduling mechanism that evolves dynamically to combine centralized and distributed strategies, improving its responsiveness to emergence, instead of the complex and optimized scheduling algorithms found in traditional approaches.

## A holonic approach to dynamic manufacturing scheduling

Leitão, Paulo; Restivo, Francisco
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
37.01%
Indexado ISI; Manufacturing scheduling is a complex combinatorial problem, particularly in distributed and dynamic environments. This paper presents a holonic approach to manufacturing scheduling, which in opposite to traditional approaches, distributes the scheduling functions over several entities, combining their calculation power and local optimization. In this scheduling and control approach, the scheduling mechanism evolves dynamically to combine optimized scheduling, achieved by central entities, and distributed scheduling, improving its responsiveness and robustness.

## Levantamento das práticas de programação detalhada da produção: um survey na indústria paulista; A survey on detailed production scheduling in manufacturing plants in São Paulo, Brazil

GIACON, Edivaldo; MESQUITA, Marco Aurélio de
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
37.04%

## Análise de desempenho de algoritmos de escalonamento de tarefas em grids computacionais usando simuladores.; Performance analysis of task scheduling algorithms in grid computing using simulators.

Rodamilans, Charles Boulhosa
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Relevância na Pesquisa
37.06%
Escalonamento em Grid tem sido vastamente estudado devido à sua grande importância para o desempenho da Grid. Dada a sua complexidade, este é subdividido em escalonamento de recursos e de aplicações. A qualidade do escalonamento está relacionada ao algoritmo de escalonamento de tarefas. O presente trabalho tem como objetivo apresentar a metodologia AGSA (Analysis of Grid Scheduling Algorithms) para a comparação de algoritmos de escalonamento de tarefas em Grid. O intuito desta metodologia é analisar o comportamento e desempenho dos algoritmos em diversos cenários. O ambiente de simulação CEGSE (Characterization oriEnted Grid Scheduling Environment) foi desenvolvido para a criação e simulação destes cenários. Os estudos de caso comprovam a eficácia da metodologia.; Grid Scheduling has been studied because it is very important for Grid performance. Due Grid Scheduling's complexity, it is subdivided in resource and application scheduling. The quality of scheduling is related a tasks scheduling algorithm. The dissertation presents the AGSA (Analysis of Grid Scheduling Algorithms) methodology for comparison of Grid Scheduling Algorithms in Grid Computing. The methodology purpose is the behavior and performance analysis of algorithms in various scenarios. The CEGSE (Characterization oriEnted Grid Scheduling Environment) simulation environment is developed for this scenarios create and simulate. The case studies ratify the methodology efficiency.

## Implantação de sistemas de programação detalhada da produção: levantamento das práticas de programação da produção na indústria.; Implantation of systems of production scheduling: survey of the practical of the production scheduling in the industry.

Giacon, Edivaldo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Relevância na Pesquisa
37.06%

## Uma abordagem orientada a sistemas para otimização de escalonamento de processos em grades computacionais; A system-centric approach for process scheduling optimization in computational grids

Gabriel, Paulo Henrique Ribeiro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Relevância na Pesquisa
37.09%

## Algoritmos para escalonamento de tarefas dependentes representadas por grafos acíclicos direcionados em grades computacionais; Scheduling algorithms for dependent tasks represented by directed acyclic graphs on computational grids

Luiz Fernando Bittencourt
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Relevância na Pesquisa
37.06%

## Workforce scheduling em ambientes multiskilled

Godinho, Ana Raquel Duarte
Relevância na Pesquisa
37.07%

## Scheduling Medical Application Workloads on Virtualized Computing Systems

Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
37.04%
This dissertation presents and evaluates a methodology for scheduling medical application workloads in virtualized computing environments. Such environments are being widely adopted by providers of “cloud computing” services. In the context of provisioning resources for medical applications, such environments allow users to deploy applications on distributed computing resources while keeping their data secure. Furthermore, higher level services that further abstract the infrastructure-related issues can be built on top of such infrastructures. For example, a medical imaging service can allow medical professionals to process their data in the cloud, easing them from the burden of having to deploy and manage these resources themselves. In this work, we focus on issues related to scheduling scientific workloads on virtualized environments. We build upon the knowledge base of traditional parallel job scheduling to address the specific case of medical applications while harnessing the benefits afforded by virtualization technology. To this end, we provide the following contributions: An in-depth analysis of the execution characteristics of the target applications when run in virtualized environments. A performance prediction methodology applicable to the target environment. A scheduling algorithm that harnesses application knowledge and virtualization-related benefits to provide strong scheduling performance and quality of service guarantees. In the process of addressing these pertinent issues for our target user base (i.e. medical professionals and researchers)...

## Chain-based scheduling: Part I - loop transformations and code generation

Tang, Peiyi
Tipo: Working/Technical Paper Formato: 249583 bytes; 356 bytes; application/pdf; application/octet-stream
EN_AU
Relevância na Pesquisa
37.04%
Chain-based scheduling [1] is an efficient partitioning and scheduling scheme for nested loops on distributed-memory multicomputers. The idea is to take advantage of the regular data dependence structure of a nested loop to overlap and pipeline the communication and computation. Most partitioning and scheduling algorithms proposed for nested loops on multicomputers [1,2,3] are graph algorithms on the iteration space of the nested loop. The graph algorithms for partitioning and scheduling are too expensive (at least O(N), where N is the total number of iterations) to be implemented in parallelizing compilers. Graph algorithms also need large data structures to store the result of the partitioning and scheduling. In this paper, we propose compiler loop transformations and the code generation to generate chain-based parallel codes for nested loops on multicomputers. The cost of the loop transformations is O(nd), where n is the number of nesting loops and d is the number of data dependences. Both n and d are very small in real programs. The loop transformations and code generation for chain-based partitioning and scheduling enable parallelizing compilers to generate parallel codes which contain all partitioning and scheduling information that the parallel processors need at run time.; no

## Local Scheduling out-performs Gang Scheduling on a Beowulf Cluster

Strazdins, Peter; Uhlmann, John
Tipo: Working/Technical Paper Formato: 119634 bytes; 356 bytes; application/pdf; application/octet-stream
EN_AU
Relevância na Pesquisa
37.07%
Gang Scheduling and related techniques are widely believed to be necessary for efficient job scheduling on distributed memory parallel computers. This is because they minimize context switching overheads and permit the parallel job currently running to progress at the fastest possible rate. However, in the case of cluster computers, and particularly those with COTS networks, these benefits can be overwhelmed in the multiple job time-sharing context by the loss the ability to utilize the CPU for other jobs when the current job is waiting for messages. Experiments on a Linux Beowulf cluster with 100 Mb fast Ethernet switches are made comparing the SCore buddy-based gang scheduling with local scheduling (provided by the Linux 2.4 kernel with MPI implemented over TCP/IP). Results for communication-intensive numerical applications on 16 nodes reveal that gang scheduling results in `slowdowns' up to a factor of two greater for 8 simultaneous jobs. This phenomenon is not due to any deficiencies in SCore but due to the relative costs of context switching versus message overhead, and we exxpect similar results will hold for any gang scheduling implementation. A performance analysis of local scheduling indicates that cache pollution due to context switching is more significant than the direct context switching overhead on the applications studied. When this is taken into account...

## Multi-agent system for distributed manufacturing scheduling with genetic algorithms and tabu search

Tipo: Patente
Relevância na Pesquisa
37.07%
Computerized scheduling methods and computerized scheduling systems according to exemplary embodiments. A computerized scheduling method may be stored in a memory and executed on one or more processors. The method may include defining a main multi-machine scheduling problem as a plurality of single machine scheduling problems; independently solving the plurality of single machine scheduling problems thereby calculating a plurality of near optimal single machine scheduling problem solutions; integrating the plurality of near optimal single machine scheduling problem solutions into a main multi-machine scheduling problem solution; and outputting the main multi-machine scheduling problem solution.

## Selection Constructive based Hyper-heuristic for Dynamic Scheduling

Gomes, Sílvia Raquel Pinto
Fonte: Instituto Politécnico do Porto Publicador: Instituto Politécnico do Porto
Relevância na Pesquisa
37.07%
A função de escalonamento desempenha um papel importante nos sistemas de produção. Os sistemas de escalonamento têm como objetivo gerar um plano de escalonamento que permite gerir de uma forma eficiente um conjunto de tarefas que necessitam de ser executadas no mesmo período de tempo pelos mesmos recursos. Contudo, adaptação dinâmica e otimização é uma necessidade crítica em sistemas de escalonamento, uma vez que as organizações de produção têm uma natureza dinâmica. Nestas organizações ocorrem distúrbios nas condições requisitos de trabalho regularmente e de forma inesperada. Alguns exemplos destes distúrbios são: surgimento de uma nova tarefa, cancelamento de uma tarefa, alteração na data de entrega, entre outros. Estes eventos dinâmicos devem ser tidos em conta, uma vez que podem influenciar o plano criado, tornando-o ineficiente. Portanto, ambientes de produção necessitam de resposta imediata para estes eventos, usando um método de reescalonamento em tempo real, para minimizar o efeito destes eventos dinâmicos no sistema de produção. Deste modo, os sistemas de escalonamento devem de uma forma automática e inteligente, ser capazes de adaptar o plano de escalonamento que a organização está a seguir aos eventos inesperados em tempo real. Esta dissertação aborda o problema de incorporar novas tarefas num plano de escalonamento já existente. Deste modo...

## Provably Efficient Adaptive Scheduling for Parallel Jobs

He, Yuxiong; Hsu, Wen Jing; Leiserson, Charles E.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 142623 bytes; application/pdf
EN
Relevância na Pesquisa
37.07%

## Cotas para el precio de la anarquía de juegos de Scheduling

Rivera Letelier, Orlando Luis
Tipo: Tesis
ES
Relevância na Pesquisa
37.07%
Ingeniero Civil Matemático; El objetivo principal del presente trabajo de memoria de título es el cálculo de cotas para precio de la anarquía de algunos juegos asociados a problemas de scheduling. Se comienza realizando una revisión general de lo que son los problemas de scheduling, un algoritmo de aproximación y la relación que existe entre teoría de juegos y los problemas de scheduling. Ahí se identifica el cuociente de aproximación del algoritmo de Smith para problemas de scheduling, con el precio de la anarquía de un juego asociado. Se realiza también una revisión de los principales resultados conocidos útiles para el presente trabajo. Más adelante se calcula el precio de la anarquía para ciertos juegos de scheduling donde la función objetivo es la suma ponderada de los tiempos de completación. Se demuestra que en el caso de máquinas idénticas, el precio de la anarquía en estrategias mixtas es 3/2. Se demuestra también que en máquinas paralelas con velocidades, el precio de la anarquía es mayor o igual a 2. Por último, se prueba acá que en el caso en que todos los trabajos tienen el mismo tamaño, el precio de la anarquía del juego de scheduling en máquinas paralelas con velocidades y suma ponderada de los tiempos de completación como función objetivo es 1. Para seguir se estudia el juego asociado al problema de scheduling en el cual la función objetivo es la suma de los tiempos de completación...

## Design of Scheduling Algorithms Using Game Theoretic Ideas

Kulkarni, Janardhan Dattatreya
Tipo: Dissertação
Relevância na Pesquisa
37.14%

Scheduling a set of jobs over a collection of machines to optimize a certain quality-of-service measure is one of the most important research topics in both computer science theory and practice. In this thesis, we design algorithms that optimize {\em flow-time} (or delay) of jobs for scheduling problems that arise in a wide range of applications. We consider the classical model of unrelated machine scheduling and resolve several long standing open problems; we introduce new models that capture the novel algorithmic challenges in scheduling jobs in data centers or large clusters; we study the effect of selfish behavior in distributed and decentralized environments; we design algorithms that strive to balance the energy consumption and performance.

The technically interesting aspect of our work is the surprising connections we establish between approximation and online algorithms, economics, game theory, and queuing theory. It is the interplay of ideas from these different areas that lies at the heart of most of the algorithms presented in this thesis.

The main contributions of the thesis can be placed in one of the following categories.

1. Classical Unrelated Machine Scheduling: We give the first polygorithmic approximation algorithms for minimizing the average flow-time and minimizing the maximum flow-time in the offline setting. In the online and non-clairvoyant setting...

## Proposed Class Scheduling Models (Initial, Alternative 1, Alternative 2, Sample)

Naveda, Fernando; Calendar Conversion Scheduling Committee
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Trabalho em Andamento
EN_US
Relevância na Pesquisa
46.75%
Proposed Class Scheduling Models for Calendar Conversion (Initial, Alternative 1, Alternative 2, Sample)

## Reasons for the low usage of scheduling software and the difference in production performance between users and nonusers of scheduling software from a lean manufacturing perspective

Yveborg, Sandra
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
EN_US
Relevância na Pesquisa
37.16%
It is more important than ever for printers to improve efficiency and productivity, and the means for doing so are available. Computer-assisted scheduling is one method that is claimed to increase throughput speed and reduce costs, among other benefits. Recently, scheduling applications have started to increase in popularity, and many management information systems (MISs) have built-in scheduling features. However, only 15% of the companies that own scheduling software utilize it. The first part of this research project seeks to determine the reasons for the low usage. Another way to increase efficiency is through Lean manufacturing, a strategy for eliminating non-value-added activities, such as defects, excess inventory, and overproduction. Lean manufacturing and computer-assisted scheduling share many of the same objectives. The second part of the research project seeks to determine whether or not there is a difference in production performance between users and nonusers of scheduling software from a lean manufacturing perspective. The analysis is based on data collected through an email questionnaire from 60 commercial printing companies in the U.S. It was found that the surveyed companies who own scheduling software but do not use it...

## A Comparison of Local and Gang Scheduling on a Beowulf Cluster

Strazdins, Peter; Uhlmann, John
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
37.1%
Gang Scheduling and related techniques are widely believed to be necessary for efficient job scheduling on distributed memory parallel computers. This is because they minimize context switching overheads and permit the parallel job currently running to progress at the fastest possible rate. However, in the case of cluster computers, and particularly those with COTS networks, these benefits can be outweighed in the multiple job time-sharing context by the loss the ability to utilize the CPU for other jobs when the current job is waiting for messages. Experiments on a Linux Beowulf cluster with 100 Mb fast Ethernet switches are made comparing the SCore buddy-based gang scheduling with local scheduling (provided by the Linux 2.4 kernel with MPI implemented over TCP/IP). Results for communication-intensive numerical applications on 16 nodes reveal that gang scheduling results in 'slowdowns ' up to a factor of two greater for 8 simultaneous jobs. This phenomenon is not due to any deficiencies in SCore but due to the relative costs of context switching versus message overhead, and we expect similar results will hold for any gang scheduling implementation. A performance analysis of local scheduling indicates that cache pollution due to context switching is more significant than the direct context switching overhead on the applications studied. When this is taken into account...

## Integrated short- and medium-term underground mine production scheduling

Nehring,M; Topal,E; Kizil,M.; Knights,P
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
The development of short- and medium-term mine production schedules in isolation from each other has meant that only a local optimum can be achieved when each scheduling phase is carried out. The globally optimal solution, however, can be achieved when integrating scheduling phases and accounting for the interaction between short-term and medium-term activities simultaneously. This paper addresses the task of integrating short- and medium-term production plans by combining the short-term objective of minimizing deviation from targeted mill feed grade with the medium-term objective of maximizing net present value (NPV) into a single mathematical optimization model. A conceptual sublevel stoping operation comprising 30 stopes is used for trialling segregated and integrated scheduling approaches. Segregated medium- and short-term scheduling using separate models achieved an NPV of $42 654 456. The final scheduling approach involved integrating the two scheduling horizons using the newly-developed globally optimal integrated production scheduling model to achieve an NPV of$42 823 657 with smoother mill feed grade. The larger the stope data set, the larger the difference between the two scheduling approaches is likely to be. At the very least...