Search results for "OPERATIONS"
showing 10 items of 1692 documents
Scatter search for an uncapacitated p-hub median problem
2015
Scatter search is a population-based method that has been shown to yield high-quality outcomes for combinatorial optimization problems. It uses strategies for combining solution vectors that have proved effective in a variety of problem settings. In this paper, we present a scatter search implementation for an NP -hard variant of the classic p-hub median problem. Specifically, we tackle the uncapacitated r-allocation p-hub median problem, which consists of minimizing the cost of transporting the traffics between nodes of a network through special facilities that act as transshipment points. This problem has a significant number of applications in practice, such as the design of transportati…
A hybrid evolution strategy for the open vehicle routing problem
2010
This paper presents a hybrid evolution strategy (ES) for solving the open vehicle routing problem (OVRP), which is a well-known combinatorial optimization problem that addresses the service of a set of customers using a homogeneous fleet of non-depot returning capacitated vehicles. The objective is to minimize the fleet size and the distance traveled. The proposed solution method manipulates a population of @m individuals using a (@m+@l)-ES; at each generation, a new intermediate population of @l offspring is produced via mutation, using arcs extracted from parent individuals. The selection and combination of arcs is dictated by a vector of strategy parameters. A multi-parent recombination …
A Population-Based Approach to the Resource-Constrained Project Scheduling Problem
2004
We present a population-based approach to the RCPSP. The procedure has two phases. The first phase handles the initial construction of a population of schedules and these are then evolved until high quality solutions are obtained. The evolution of the population is driven by the alternative application of an efficient improving procedure for locally improving the use of resources, and a mechanism for combining schedules that blends scatter search and path relinking characteristics. The objective of the second phase is to explore in depth those vicinities near the high quality schedules. Computational experiments on the standard j120 set, generated using ProGen, show that our algorithm produ…
Food Security Is None Of Your Business? Food Supply Chain Management In Support Of A Sustainable Food System
2017
Food security is the principal outcome of any given food system and it can be defined in terms of a sustainable food system where the core goal is to feed everyone sustainably, equitably and healthily. A sustainable food system addresses needs for availability, affordability and accessibility, is diverse, ecologically-sound and resilient, and builds the capabilities and skills necessary for future generations. This paper identifies the essential elements of food supply chain management in support of a sustainable food system, which ultimately enhances food security. The existing food supply chain and food system literature is synthesized in order to study the correspondence between public i…
Age group athletes in inline skating: decrease in overall and increase in master athlete participation in the longest inline skating race in Europe -…
2013
Uwe Teutsch,1 Beat Knechtle,1,2 Christoph Alexander Rüst,1 Thomas Rosemann,1 Romuald Lepers31Institute of General Practice and Health Services Research, University of Zurich, Zurich, Switzerland; 2Gesundheitszentrum St Gallen, St Gallen, Switzerland; 3INSERM U1093, Faculty of Sport Sciences, University of Burgundy, Dijon, FranceBackground: Participation and performance trends in age group athletes have been investigated in endurance and ultraendurance races in swimming, cycling, running, and triathlon, but not in long-distance inline skating. The aim of this study was to investigate trends in participation, age, and performance in the longest inline race in Europe, the Inline One-E…
Which firms benefit from investments in green energy technologies? : The effect of energy costs
2019
Abstract Firms will invest in green energy technologies only if these investments have an economic pay-off. Based on unique firm-level data from Austria, Germany, and Switzerland, we find that the marginal effect of investments in green energy technologies on productivity is positive only for the 19% of firms with the highest energy costs. These results have major implications for companies and policy makers regarding the design of green energy policies and incentives.
Quizz CE Lesson 1 Ops Mgmt 2223- revised
2023
Prueba de evaluación continua Lección 1
Quizz CE Lesson 4 + 7 Ops Mgmt 2223- revised
2023
El document forma part dels materials docents programats mitjançant l'ajut del Servei de Política Lingüística de la Universitat de València Prueba evaluación continua lecciones 4 y 7
Quizz CE Lesson 2 Ops Mgmt 2223- revised
2023
Prueba evaluación continua Lección 2
Quizz CE Lesson 5 + 8 Ops Mgmt 2223- revised
2023
El document forma part dels materials docents programats mitjançant l'ajut del Servei de Política Lingüística de la Universitat de València Prueba evaluación continua lecciones 5 y 8