Search results for "Operations Research"
showing 10 items of 1297 documents
Multiple-criteria cash-management policies with particular liquidity terms
2019
Abstract Eliciting policies for cash management systems with multiple assets is by no means straightforward. Both the particular relationship between alternative assets and time delays from control decisions to availability of cash introduce additional difficulties. Here we propose a cash management model to derive short-term finance policies when considering multiple assets with different expected returns and particular liquidity terms for each alternative asset. In order to deal with the inherent uncertainty about the near future introduced by cash flows, we use forecasts as a key input to the model. We express uncertainty as lack of predictive accuracy and we derive a deterministic equiv…
The potential of optimization in communal routing problems: case studies from Finland
2009
Abstract: In many European countries, municipalities offer their inhabitants a wide variety of social services. In this paper we will focus on efficiently scheduling home care, transportation of the elderly, and home meal delivery. These so-called municipal or communal routing problems can be modeled as different variants of the vehicle routing problem, a well-known optimization problem from the literature. We present a focused literature review and report on case studies using Finnish data. The computational results show that there is a significant potential for cost savings for all applications considered.
Integer programming models for the pre-marshalling problem
2019
[EN] The performance of shipping companies greatly depends on reduced berthing times. The trend towards bigger ships and shorter berthing times places severe stress on container terminals, which cannot simply increase the available cranes indefinitely. Therefore, the focus is on optimizing existing resources. An effective way of speeding up the loading/unloading operations of ships at the container terminal is to use the idle time before the arrival of a ship for sorting the stored containers in advance. The pre-marshalling problem consists in rearranging the containers placed in a bay in the order in which they will be required later, looking for a sequence with the minimum number of moves…
Optimization of Data Harvesters Deployment in an Urban Areas for an Emergency Scenario
2013
International audience; Since its appearance in the VANETs research community, data collection where vehicles have to explore an area and collect various local data, brings various issues and challenges. Some architectures were proposed to meet data collection requirements. They can be classified into two categories: Decentralized and Centralized self-organizing where different components and techniques are used depending on the application type. In this paper, we treat time-constrained applications in the context of search and rescue missions. For this reason, we propose a centralized architecture where a central unit plans and manages a set of vehicles namely harvesters to get a clear ove…
A combined interval-valued ELECTRE TRI and TOPSIS approach for solving the storage location assignment problem
2019
Abstract Efficiency and effectiveness of logistic activities, in general, and of distribution networks, in particular, are largely influenced by the way warehouses operate as nodes of these networks. In recent years, warehouse management has undergone major changes due to the increase of e-commerce and competition in time-reduction. Despite that, logistic costs of warehouse processes (e.g. receiving, storage, order picking and shipping, etc.) are still often high. Referring to the order picking process, related activities may be optimized by a proper assignment of products to storage locations. In the literature, this problem is known as Storage Location Assignment Problem (SLAP). Due to th…
Treating Ordinal Criteria in Stochastic Weight Space Analysis
2001
We consider discrete co-operative group decision-making problems and suggest a method that is aimed at providing descriptive information about the acceptability of different decision alternatives. The method is a new variant of the Stochastic Multicriteria Acceptability Analysis (SMAA) method for discrete multicriteria decision-making problems with multiple decision makers. The new method is designed for problems where criterion information is completely or partially ordinal, that is, experts (or decision makers) have ranked the alternatives criterion-wise. The approach is particularly suitable for group decision making where either no or only partial preference information is available ass…
Multicriteria Decision Analysis for Choosing the Remediation Method for a Landfill Based on Mixed Ordinal and Cardinal Information
2009
We describe a real-life application of a multicriteria method in the context of remediating a landfill in Finland. The landfill was used for dumping industrial waste during the years 1950 to 1965. During that time many harmful chemicals were stored in landfills among other waste. Therefore, this—and possibly several other—landfills have to be remediated. In this application, seven different remediation options were evaluated based on 13 criteria. For some criteria, cardinal measures with associated uncertainties were obtained. For other criteria, only ordinal (ranking) information was available. The problem was analyzed using the Stochastic Multicriteria Acceptability Analysis with Ordinal …
Time and strategy: towards a multitemporal view of the firm
2004
This paper takes into consideration the main views underlying the theory of the resource based firm within strategy studies, underscoring their fundamental monotemporal nature and proposing a way to elaborate a multi‐temporal view of the firm. By analyzing the link between the time concepts used as bases for the formulation of studies within the strategy field and the types of actor behavior implicitly (or explicitly) entailed by such time concepts, the paper shows the inadequacy of any one of the two monotemporal views of the resource‐based firm to encompass all of the main actor behaviors on which the firm's survival and success increasingly rests. The paper draws on the Austrian process …
Managing innovation of care services: An exploration of Norwegian municipalities
2016
AbstractThe social impact of care services provided by the public sector is significant. Nevertheless, these services have received relatively little attention from prior innovation management practices research. This paper addresses this gap by raising the question: What characterises management-driven innovation processes in public organisations providing care services? The qualitative exploration of this question is based on in-depth interviews with key managers in three Norwegian municipalities, and in-depth observation of one ongoing innovation initiative in one municipality. Our findings supplement the findings of prior research by showing that different actors are involved in differe…
More planet and less profit? The ethical dilemma of an oil producing nation
2019
Every oil producing nation is confronted with a complex and fundamental ethical dilemma. On the one hand, there are moral arguments for the nation to use the petroleum resource for the benefit of society and make it available for countries who do not have this natural resource endowment. On the other hand, there are moral arguments for not extracting and using fossil fuels because of CO2 emissions. In short, this creates tension between the need for government revenues to finance welfare benefits and the objective of preserving the environment. A complicating factor is that a nation's domestic oil and gas activities are in its nature global because the activities have a direct impact on the…