Search results for "Operations Research"
showing 10 items of 1297 documents
Success factors for information technology supported international technology transfer: Finding expert consensus
2006
Information technology (IT)-supported international technology transfer (ITT) is complex, risky, and fails often. No empirical studies are available on the factors that affect the success of IT-supported ITT. We review applicable theories (i.e. diffusion of innovation theory) and empirical research in conventional technology transfer to develop such a model. We carry out a multiple focus group method to rank factors that affect the success of IT-supported ITT and then apply a branch and bound method to derive a consensus ranking of these factors. The identified consensus ranking sheds light on factors that are similar to those of DOI theory and suggests a pattern of factors that affect IT-s…
A model of goal dynamics in technology-based organizations
2011
The purpose of the present work is to build a suitable system dynamics model for goal dynamics in organizations, as proposed by Barlas and Yasarcan (2008). The proposed model does not bear any ambition of being exhaustive: the main objective of this paper is to propose a model of goal dynamics in which Goal Setting, Management by Objectives and Training are viewed as human resource practices able to enhance workers' goal commitment, and therefore, improve organizational performance. In the first part of this paper, an analysis of the Goal Setting Theory and the role of goal setting practices, in bettering worker's performance, are stressed. In the second part, a case-study, the causal loop …
2016
Planning Rehabilitation Actions on Water Distribution Networks in Condition of Data Scarcity
2011
The paper shows a viable approach to the selection of water networks rehabilitation actions, in condition of data scarcity and uncertainty, based on the use of four concise performance literature indices, allowing the analysis and identification of efficient, reliable and robust rehabilitation alternatives, even if assessed on the basis of a relatively small amount of data. A promising statistical sampling method of water consumptions is also described, that may be fruitfully employed within the proposed approach for drafting water balances at network district scale in order to quantify the extent of leakages. The illustrated case study shows that the selected indices are capable to describ…
Including the environmental criteria when selecting a wastewater treatment plant
2014
Abstract Life Cycle Assessment (LCA) is a methodology to generate environmental impact estimates associated with the life cycle stages of a product or process. The approach facilitates a more comprehensive outlook of the end-of-pipe process impacts, in which wastewater treatment plants (WWTPs) are included. Here we describe the implementation of the LCA methodology within a knowledge-based Decision support system (DSS) in order to include the environmental criteria to the decision making process when selecting the most appropriate process flow diagrams for specific scenarios. A sample group of 22 actual operating facilities in Spain, corresponding to five different typologies were assessed …
Split-Delivery Capacitated Arc-Routing Problem: Lower Bound and Metaheuristic
2010
International audience; This paper proposes lower and upper bounds for the split-delivery capacitated arc-routing problem (SDCARP), a variant of the capacitated arc-routing problem in which an edge can be serviced by several vehicles. Recent papers on related problems in node routing have shown that this policy can bring significant savings. It is also more realistic in applications such as urban refuse collection, where a vehicle can become full in the middle of a street segment. This work presents the first lower bound for the SDCARP, computed with a cutting plane algorithm and an evolutionary local search reinforced by a multistart procedure and a variable neighborhood descent. Tests on …
Real-time weighting optimization in Chinese Postman Problem
2013
International audience; In this study, based on real-time constraint, an optimization method is proposed for solving the problem of the optimal tour. For that, we will construct a graph containing the real-time state of traffic. The collected data will be used to predict the future state traffic and to give an optimized cost of the tour. This optimization is tested in different sizes of the road networks. The results show that the proposed method is efficient and effective in solving the Chinese Postman Problem in real-time.
A Note on the Flaws of MFA (Minimal Flow Analysis)
2012
MFA (Minimal Flow Analysis) is a method of qualitative input-output analysis used for identifying national of regional industrial clusters. It is based on the analysis of layers (in an input-output model, flow matrices generated at each iteration toward equilibrium). We show through theory that all normalized layers (column-coefficient matrices computed from each layer) are equal in MFA. This is illustrated by an application to France's 2009 input-output table. Therefore, the information brought by one layer is identical to those of another layer: layers bring no specific information, which unfortunately implies that MFA is not a good tool to study intersectoral linkages, despite the intere…
Multi-step ahead electricity price forecasting using a hybrid model based on two-layer decomposition technique and BP neural network optimized by fir…
2017
In the deregulated competitive electricity market, the price which reflects the relationship between electricity supply and demand is one of the most important elements, making it crucial for all market participants to precisely forecast the electricity price. However, electricity price series usually has complex features such as non-linearity, non-stationarity and volatility, which makes the price forecasting turn out to be very difficult. In order to improve the accuracy of electricity price forecasting, this paper first proposes a two-layer decomposition technique and then develops a hybrid model based on fast ensemble empirical mode decomposition (FEEMD), variational mode decomposition …
fuzzy approach to the robust facility layout in uncertain production environments
2001
The proposed method approaches the problem of the optimal facility layout using fuzzy theory. The optimal layout is a robust layout that minimizes the total material handling cost, when the product market demands are uncertain variables, which are defined as fuzzy numbers. Since each department has a limited production capacity, not all possible combinations, deriving from each product's market demand, are taken into account because some combination could exceed the overall department's productivity. Therefore, the optimal solution results by solving a 'constrained' fuzzy optimization problem, in which the fuzzy material handling costs corresponding to the layouts are evaluated, and a ranki…