Search results for "Operations Research"
showing 10 items of 1297 documents
Automated agent-based system for weather information
2009
Road accidents are well correlated with bad weather conditions. In traffic management, several strategies have been considered in order to reduce this kind of accidents. Weather problems can cause difficult situations for the traffic management decision-makers. They need to analyze and absorb a large quantity of information in order to solve some problems due to bad weather. An automated agent-based system is a good solution to help decision-makers in the management of weather information to road users in relation to traffic conditions.In this paper, a distributed system based in autonomous agents and rules for road weather information has been proposed. Also the detection procedure is expl…
Are Spanish SMEs good places to work?
2012
PurposeThis paper aims to perform a descriptive analysis of the current degree of development and application of work‐life balance policies in Spanish SMEs, examining the differences that arise due to ownership structure (family owned business versus non‐family owned business) and presenting an in‐depth analysis of the variables that influence managers' attitudes towards work‐life balance policies.Design/methodology/approachStructured interviews with SME managers were performed.FindingsThe presence of those polices is small, although the situation differs depending on the type of policy. Differences in ownership structure do not imply significantly different behavior with regard to the intr…
Constrained consistency enforcement in AHP
2020
Abstract Decision-making in the presence of intangible elements must be based on a robust, but subtle, balance between expert know-how and judgment consistency when eliciting that know-how. This balance is frequently achieved as a trade-off reached after a feedback process softens the tension frequently found between one force steadily pulling towards (full) consistency, and another force driven by expert feeling and opinion. The linearization method, developed by the authors in the framework of the analytic hierarchy process, is a pull-towards-consistency mechanism that shows the path from an inconsistent body of judgment elicited from an expert towards consistency, by suggesting optimal c…
The Network Balance Realized by Routing Organization System
2011
In the presented paper, we propose to exploit routing organization for the purpose of managing network resources. According to our assumptions, we have the same quantity of materials, objects, tokens, tools etc. at our disposal in every node of the network. During network operation we must distribute resources between these nodes. It should be carried out as instantaneously and as economically as possible. Multi-Agent Systems are also used to deal with this kind of tasks and the centralised algorithms presented in this paper are to be used to measure the efficiency of the distributed MAS solution. From the logistical point of view, we have a sequence of stages with different states of token…
Dasymetric distribution of votes in a dense city
2017
[EN] A large proportion of electoral analyses using geography are performed on a small area basis, such as polling units. Unfortunately, polling units are frequently redrawn, provoking breaks in their data series. Previous electoral results play a key role in many analyses. They are used by political party workers and journalists to present quick assessments of outcomes, by political scientists and electoral geographers to perform detailed scrutinizes and by pollsters and forecasters to anticipate electoral results. In this paper, we study to what extent more complex geographical approaches (based on a proper location of electors on the territory using dasymetric techniques) are of value in…
The pricing capability lifecycle of digital innovations
2021
The pricing capability provides a basis for firms’ competitive advantage. However, to date, the literature has not investigated how this capability forms, develops, and matures. In this study, we define the pricing capability as a dynamic capability consisting of three operational building blocks (tools and data, human and relational resources, and processes, routines, and mechanisms) as well as two dynamic capability building blocks (alertness and responsiveness, and value-based strategic thinking). Furthermore, we propose the pricing capability lifecycle of digital innovations that incorporates insights of the dynamic capabilities view (DCV). Based on a longitudinal multi-case study of fi…
Stationary battery systems in the main world markets: Part 2: Main trends and prospects
2017
Stationary battery systems are gaining a lot of interest in recent years, mainly because of their ability to balance generation and demand of electricity over time. The intermittent nature of renewable generation connected to the power grid is causing major stability and reliability issues in the power system, that can be solved also using stationary storage systems, able to provide the ancillary services necessary to the proper operation of the power network. Despite the considerable advantages offered by these technologies, the electrochemical storage industry is still in the nascent state and it is important to identify the main trends and prospects in relation to future technical develo…
A comparison of HDFS compact data formats: Avro versus Parquet
2017
In this paper, file formats like Avro and Parquet are compared with text formats to evaluate the performance of the data queries. Different data query patterns have been evaluated. Cloudera’s open-source Apache Hadoop distribution CDH 5.4 has been chosen for the experiments presented in this article. The results show that compact data formats (Avro and Parquet) take up less storage space when compared with plain text data formats because of binary data format and compression advantage. Furthermore, data queries from the column based data format Parquet are faster when compared with text data formats and Avro. Article in English. HDFS glaustųjų duomenų formatų palyginimas: Avro prieš Parquet…
SOCIAL NETWORKS, BIG DATA AND TRANSPORT PLANNING
2016
[EN] The characteristics of people who are related or tied to each individual affects her activity-travel behavior. That influence is especially associated to social and recreational activities, which are increasingly important. Collecting high quality data from those social networks is very difficult using traditional travel surveys, because respondents are asked about their general social life, which is most demanding to remember that specific facts. On the other hand, currently there are different potential sources of transport data, which is characterized by the huge amount of information available, the velocity with it is obtained and the variety of format in which is presented. This s…
A new compact formulation for the discrete p-dispersion problem
2017
Abstract This paper addresses the discrete p -dispersion problem (PDP) which is about selecting p facilities from a given set of candidates in such a way that the minimum distance between selected facilities is maximized. We propose a new compact formulation for this problem. In addition, we discuss two simple enhancements of the new formulation: Simple bounds on the optimal distance can be exploited to reduce the size and to increase the tightness of the model at a relatively low cost of additional computation time. Moreover, the new formulation can be further strengthened by adding valid inequalities. We present a computational study carried out over a set of large-scale test instances i…