Search results for "Operation"
showing 10 items of 2969 documents
Discrete frequency models for inventory management – an introduction
2001
Abstract The paper deals with the problem of devising a periodic replenishment policy when orders must be periodic, but only a given, discrete set of order frequencies can be used. The multi-item, instantaneous replenishment case with known demand is studied. In particular, staggering policies somehow arranging replenishments not to come at the same time instants are considered. The paper is composed of three parts: first, a taxonomy of several versions of the discrete frequency problem is proposed, according to different elements; in the second part, a general mixed integer programming model is proposed which is able to capture the peculiarities of the whole spectrum of this kind of proble…
More firms, more competition? The case of the fourth operator in France's mobile phone market
2010
Accepted, Forthcoming; International audience; To foster competition the French government authorized a fourth operator, ‘Free', to enter the country's mobile phone market at the end of 2009 alongside Orange, SFR and Bouygues Telecom (BT), who held respectively one-half, one-third and one-sixth of the market. By using a stylized model of France's phone market, we have examined what we call the regulator's nightmares and dreams. If Cournot competition is in place before Free's entry, minimizing the total profit fails to maximize the consumer surplus and the total surplus; the maximum most realistic price fall is 6.7% compared to three-way competition and could be 1.7% only; if Orange, SFR an…
A branch & bound algorithm for cutting and packing irregularly shaped pieces
2013
Abstract Cutting and packing problems involving irregular shapes, usually known as Nesting Problems, are common in industries ranging from clothing and footwear to furniture and shipbuilding. Research publications on these problems are relatively scarce compared with other cutting and packing problems with rectangular shapes, and are focused mostly on heuristic approaches. In this paper we make a systematic study of the problem and develop an exact Branch & Bound Algorithm. The initial existing mixed integer formulations are reviewed, tested and used as a starting point to develop a new and more efficient formulation. We also study several branching strategies, lower bounds and procedures f…
A problem-adjusted genetic algorithm for flexibility design
2013
Many present markets for goods and services have highly volatile demand due to short life cycles and strong competition in saturated environments. Determination of capacity levels is difficult because capacities often need to be set long before demand realizes. In order to avoid capacity-demand mismatches, operations managers employ mix-flexible resources which allow them to shift excess demands to unused capacities. The Flexibility Design Problem (FDP) models the decision on the optimal configuration of a flexible (manufacturing) network. FDP is a difficult stochastic optimization problem, for which traditional exact approaches are not able to solve but the smallest instances in reasonable…
Strategic sharing of a costly network
2012
We study minimum cost spanning tree problems for a set of users connected to a source. Prim’s algorithm provides a way of finding the minimum cost tree mm. This has led to several definitions in the literature, regarding how to distribute the cost. These rules propose different cost allocations, which can be understood as compensations and/or payments between players, with respect to the status quo point: each user pays for the connection she uses to be linked to the source. In this paper we analyze the rationale behind a distribution of the minimum cost by defining an a priori transfer structure. Our first result states the existence of a transfer structure such that no user is willing to …
Current research issues in production economics
2020
This Special Issue includes a selection of papers originally presented and discussed at the Twentieth International Working Seminar on Pro- duction and Operations Management, Innsbruck, February 19–23, 2018, and subsequently extended and improved. Production and Operations Management was established in the1970s as an academic discipline focusing on scientific topics treating the interface between engineering, management, and economics with a special emphasis on financial consequences of decisions in the produc- tion domain. The subject is interdisciplinary in nature and it therefore contains a wide range of topics. The Working Seminar included sessions such as supply chain management, innov…
Cyberloafing and cyberslacking in the workplace: systematic literature review of past achievements and future promises
2021
PurposeScholars are increasingly focusing on the adverse effects of digitization on human lives in personal and professional contexts. Cyberloafing is one such effect and digitization-related workplace behavior that has garnered attention in both academic and mainstream media. However, the existing literature is fragmented and needs to be consolidated to generate a comprehensive and contemporary overview of cyberloafing research and map its current intellectual boundaries. The purpose of this paper is to shed some light on systematic literature review (SLR) in cyberloafing and cyberslacking in the workplace.Design/methodology/approachA SLR is conducted to assimilate the existing research. A…
Fear of missing out (FoMO) among social media users: a systematic literature review, synthesis and framework for future research
2021
PurposeResearch examining the “fear of missing out” (FoMO) is increasingly prominent, with a growing number of studies exploring this phenomenon. Despite the increased academic interest, no attempts have been made to synthesize extant knowledge on FoMO. There is limited holistic understanding of its conceptualization and operationalization. To address this gap, an exhaustive systematic literature review (SLR) on FoMO is presented.Design/methodology/approachSystematic review protocols and content analysis was used to analyze and synthesize insights from 58 empirical studies obtained from four academic databases: Scopus, Web of Science, PubMed and PsycINFO.FindingsSignificant diversity in pri…
Designing multi-attribute auctions for engineering services procurement in new product development in the automotive context
2010
Abstract In recent years, use of multi-attribute auctions has been consolidating as a powerful mechanism in procurement settings where multiple drivers affect the transaction outcome. This paper provides a project management approach for multi-attribute auction design for standardized engineering services procurement in the context of new product development in automotive industry. Two variables are taken into account in the bidding process: price and duration of the given engineering activity. From a theoretical viewpoint, we fully determine optimal suppliers’ bidding strategies and expected outcomes, i.e. score/utility, price and duration, for the buyer under both first score sealed bid a…
Directional distance functions and environmental regulation
2005
Abstract In this paper we use directional technology distance functions to evaluate the impact of environmental regulations on firms’ performance. Following Fare et al. [Fare, R., Grosskopf, S., Lovell, C.A.K., Pasurka, C., 1989. Multilateral productivity comparisons when some outputs are undesirable: a nonparametric approach. The Review of Economics and Statistics 71, 90–98.], we construct an index that measures opportunity costs for individual firms arising from regulations that prevent free disposal of wastes. The methodology is applied to a sample of Spanish producers of ceramic pavements. We assume that firms maximise desirable output simultaneously reducing inputs, with no change in t…