Search results

1 – 10 of 38
Article
Publication date: 9 January 2017

Eric Alfredo Rincón-García, Miguel Ángel Gutiérrez-Andrade, Sergio Gerardo de-los-Cobos-Silva, Roman Anselmo Mora-Gutiérrez, Antonin Ponsich and Pedro Lara-Velázquez

This paper aims to propose comparing the performance of three algorithms based on different population-based heuristics, particle swarm optimization (PSO), artificial bee…

Abstract

Purpose

This paper aims to propose comparing the performance of three algorithms based on different population-based heuristics, particle swarm optimization (PSO), artificial bee colony (ABC) and method of musical composition (DMMC), for the districting problem.

Design/methodology/approach

In order to compare the performance of the proposed algorithms, they were tested on eight instances drawn from the Mexican electoral institute database, and their respective performance levels were compared. In addition, a simulated annealing-based (simulated annealing – SA) algorithm was used as reference to evaluate the proposed algorithms. This technique was included in this work because it has been used for Federal districting in Mexico since 1994. The performance of the algorithms was evaluated in terms of the quality of the approximated Pareto front and efficiency. Regarding solution quality, convergence and dispersion of the resulting non-dominated solutions were evaluated.

Findings

The results show that the quality and diversification of non-dominated solutions generated by population-based algorithms are better than those produced by Federal Electoral Institute’s (IFE’s) SA-based technique. More accurately, among population-based techniques, discrete adaptation of ABC and MMC outperform PSO.

Originality/value

The performance of three population-based techniques was evaluated for the districting problem. In this paper, the authors used the objective function proposed by the Mexican IFE, a weight aggregation function that seeks for a districting plan that represents the best balance between population equality and compactness. However, the weighting factors can be modified by political agreements; thus, the authors decided to produce a set of efficient solutions, using different weighting factors for the computational experiments. This way, the best algorithm will produce high quality solutions no matter the weighting factors used for a real districting process. The computational experiments proved that the proposed artificial bee colony and method of musical composition-based algorithms produce better quality efficient solutions than its counterparts. These results show that population-based algorithms can outperform traditional local search strategies. Besides, as far as we know, this is the first time that the method of musical composition is used for this kind of problems.

Article
Publication date: 1 June 2004

Miguel Angel Gutierrez

Although only a small percentage of the world's population has access to the Web, its influence over the world economy and society is very high. It is possible to imagine…

1215

Abstract

Although only a small percentage of the world's population has access to the Web, its influence over the world economy and society is very high. It is possible to imagine a completely different economy from the industrial one, but the potential of information and communications technology constitutes a challenge for traditional economic thought. This paper explores the characteristics of the information society and the global economy from the perspective of the developing countries of Latin America, and the potential of the digital economy to transform social relationships both universally and locally. As Latin America is about to start its third century of political autonomy, the digital revolution provides a new opportunity to articulate that freedom of action and to exercise alternative strategies.

Details

Foresight, vol. 6 no. 3
Type: Research Article
ISSN: 1463-6689

Keywords

Expert briefing
Publication date: 9 May 2016

The operation will take place under a government subsidy scheme that pays 7.50 dollars per barrel to exporters as long as the world oil price remains below 47.50 dollars…

Details

DOI: 10.1108/OXAN-DB210822

ISSN: 2633-304X

Keywords

Geographic
Topical
Content available
Article
Publication date: 9 January 2017

José M. Merigó, Salvador Linares-Mustarós and Joan Carles Ferrer-Comalat

500

Abstract

Details

Kybernetes, vol. 46 no. 1
Type: Research Article
ISSN: 0368-492X

Article
Publication date: 30 June 2022

Miguel Ángel Caminero, Ana Romero Gutiérrez, Jesús Miguel Chacón, Eustaquio García-Plaza and Pedro José Núñez

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material…

Abstract

Purpose

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In this study, 316L stainless-steel metal filled filaments were used to print metal parts using the extrusion-based fused filament fabrication (FFF) approach. The purpose of this study is to assess the effects of common FFF printing parameters on the geometric and mechanical performance of FFF manufactured 316L stainless-steel components.

Design/methodology/approach

The microstructural characteristics of the metal filled filament, three-dimensional (3D) printed green parts and final sintered parts were analysed. In addition, the dimensional accuracy of the green parts was evaluated, as well as the hardness, tensile properties, relative density, part shrinkage and the porosity of the sintered samples. Moreover, surface quality in terms of surface roughness after sintering was assessed. Predictive models based on artificial neural networks (ANNs) were used for characterizing dimensional accuracy, shrinkage, surface roughness and density. Additionally, the response surface method based on ANNs was applied to represent the behaviour of these parameters and to identify the optimum 3D printing conditions.

Findings

The effects of the FFF process parameters such as build orientation and nozzle diameter were significant. The pore distribution was strongly linked to the build orientation and printing strategy. Furthermore, porosity decreased with increased nozzle diameter, which increased mechanical performance. In contrast, lower nozzle diameters achieved lower roughness values and average deviations. Thus, it should be noted that the modification of process parameters to achieve greater geometrical accuracy weakened mechanical performance.

Originality/value

Near-dense 316L austenitic stainless-steel components using FFF technology were successfully manufactured. This study provides print guidelines and further information regarding the impact of FFF process parameters on the mechanical, microstructural and geometric performance of 3D printed 316L components.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 27 January 2021

Miguel Ángel Caminero, Ana Romero, Jesús Miguel Chacón, Pedro José Núñez, Eustaquio García-Plaza and Gloria Patricia Rodríguez

Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for…

Abstract

Purpose

Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for laser-based powder bed fusion processes. The mechanical behaviour of FFF-metal materials is highly dependent on the processing parameters, filament quality and adjusted post-processing steps. In addition, the microstructural material properties and geometric characteristics are inherent to the manufacturing process. The purpose of this study is to characterize the mechanical and geometric performance of three-dimensional (3-D) printed FFF 316 L metal components manufactured by a low-cost desktop 3-D printer. The debinding and sintering processes are carried out using the BASF catalytic debinding process in combination with the BASF 316LX Ultrafuse filament. Special attention is paid on the effects of build orientation and printing strategy of the FFF-based technology on the tensile and geometric performance of the 3-D printed 316 L metal specimens.

Design/methodology/approach

This study uses a toolset of experimental analysis techniques [metallography and scanning electron microcope (SEM)] to characterize the effect of microstructure and defects on the material properties under tensile testing. Shrinkage and the resulting porosity of the 3-D printed 316 L stainless steel sintered samples are also analysed. The deformation behaviour is investigated for three different build orientations. The tensile test curves are further correlated with the damage surface using SEM images and metallographic sections to present grain deformation during the loading progress. Mechanical properties are directly compared to other works in the field and similar additive manufacturing (AM) and Metal Injection Moulding (MIM) manufacturing alternatives from the literature.

Findings

It has been shown that the effect of build orientation was of particular significance on the mechanical and geometric performance of FFF-metal 3-D printed samples. In particular, Flat and On-edge samples showed an average increase in tensile performance of 21.7% for the tensile strength, 65.1% for the tensile stiffness and 118.3% for maximum elongation at fracture compared to the Upright samples. Furthermore, it has been able to manufacture near-dense 316 L austenitic stainless steel components using FFF. These properties are comparable to those obtained by other metal conventional processes such as MIM process.

Originality/value

316L austenitic stainless steel components using FFF technology with a porosity lower than 2% were successfully manufactured. The presented study provides more information regarding the dependence of the mechanical, microstructural and geometric properties of FFF 316 L components on the build orientation and printing strategy.

Article
Publication date: 14 August 2018

Miguel Angel Ortiz-Barrios, Zulmeira Herrera-Fontalvo, Javier Rúa-Muñoz, Saimon Ojeda-Gutiérrez, Fabio De Felice and Antonella Petrillo

The risk of adverse events in a hospital evaluation is an important process in healthcare management. It involves several technical, social, and economical aspects. The…

Abstract

Purpose

The risk of adverse events in a hospital evaluation is an important process in healthcare management. It involves several technical, social, and economical aspects. The purpose of this paper is to propose an integrated approach to evaluate the risk of adverse events in the hospital sector.

Design/methodology/approach

This paper aims to provide a decision-making framework to evaluate hospital service. Three well-known methods are applied. More specifically are proposed the following methods: analytic hierarchy process (AHP), a structured technique for organizing and analyzing complex decisions, based on mathematics and psychology developed by Thomas L. Saaty in the 1970s; decision-making trial and evaluation laboratory (DEMATEL) to construct interrelations between criteria/factors and VIKOR method, a commonly used multiple-criteria decision analysis technique for determining a compromise solution and improving the quality of decision making.

Findings

The example provided has demonstrated that the proposed approach is an effective and useful tool to assess the risk of adverse events in the hospital sector. The results could help the hospital identify its high performance level and take appropriate measures in advance to prevent adverse events. The authors can conclude that the promising results obtained in applying the AHP–DEMATEL–VIKOR method suggest that the hybrid method can be used to create decision aids that it simplifies the shared decision-making process.

Originality/value

This paper presents a novel approach based on the integration of AHP, DEMATEL and VIKOR methods. The final aim is to propose a robust methodology to overcome disadvantages associated with each method.

Details

Management Decision, vol. 56 no. 10
Type: Research Article
ISSN: 0025-1747

Keywords

Book part
Publication date: 3 June 2020

Anel Flores-Novelo, Ana Laura Bojórquez Carrillo and María Cristina Mata Castro

This chapter is about an analysis and reflection on the actions, programs, and regulatory frameworks of the Mexican government for the promotion of entrepreneurial…

Abstract

This chapter is about an analysis and reflection on the actions, programs, and regulatory frameworks of the Mexican government for the promotion of entrepreneurial activity during the twentieth century. A documentary review is presented based mainly on the presidential reports available in the virtual legal library of the National Autonomous University of Mexico, the Center for Documentation, Information, and Analysis of the Chamber of Deputies (Cámara de Diputados), and various publications of experts on economic history, considering the twentieth century: from the year 1900 with the end of the Porfiriato until the six-year term of Ernesto Zedillo that ended in 2000. The public policies of these 100 years were reviewed and based on this, was analyzed the importance assigned to the creation, development, and consolidation of companies and their importance in public policies. Special emphasis is given to instruments for the creation of new businesses or the development and strengthening of small- and medium-sized enterprises.

Article
Publication date: 25 August 2022

José Valverde-Roda, Miguel Jesús Medina Viruel, Lucía Castaño Prieto and Miguel Ángel Solano Sánchez

Gastronomy can be a key destination choice factor. As tourists, people will be able to learn more about the culture of the place through its culinary assets. This paper…

Abstract

Purpose

Gastronomy can be a key destination choice factor. As tourists, people will be able to learn more about the culture of the place through its culinary assets. This paper aims to analyse the interest and the gastronomic motivations of tourists to the city of Granada (Spain), where two important UNESCO World Heritage Sites (WHS) are included.

Design/methodology/approach

To achieve the aim of this study, fieldwork was carried out on a representative sample of tourists in Granada (Spain). Specifically, a total of 1,612 valid surveys were filled out in culinary establishments and historical sites. In these surveys, the opinion of tourists regarding gastronomy and their motivations when travelling was assessed.

Findings

The results of this research allow to make a segmentation of tourists into three groups according to their position and their interest in gastronomy based on their destination choice, distinguishing among survivors, enjoyers and experiencers’ tourists. Additionally, it is confirmed that gastronomy is shaped as a motivation that influences the level of tourist satisfaction, performing as a differentiating element that can help increase the competitiveness of the destination.

Originality/value

This research contributes to the scarce academic literature on tourism experiences in a city with WHS recognitions. This study confirms the existence of a relationship between gastronomic motivations and the level of satisfaction achieved by tourists who visit the city of Granada, where no similar studies were found. In addition, this work confirms the connection between gastronomy and culture.

Details

British Food Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 28 October 2013

Luz del Carmen Díaz-Peña, Anselmo Salvador Chavez-Capo, Miguel Angel Tinoco-Castrejón, Genoveva Rosano-Ortega and Beatriz Pérez-Armendariz

– This paper aims to assess the biodiesel value chain produced by the State of Chiapas and, through a financial model, determines its profitability and feasibility as a business.

Abstract

Purpose

This paper aims to assess the biodiesel value chain produced by the State of Chiapas and, through a financial model, determines its profitability and feasibility as a business.

Design/methodology/approach

The literature review was based on searching in journal databases and in official web sites. To quantify value chain activities, a questionnaire was used to interview project leader. Besley's methodology was used to create the financial model and determine the net present value (NPV). Finally, the SWOT model summarized the analysis based on the results obtained.

Findings

All the costs of the value chain were calculated and the results show that the greatest cost corresponds to the “internal logistical activity,” with 74 percent of the total cost/liter. The NPV of the project was positive and the project was thus considered financially feasible.

Practical implications

Biodiesel production plants must know the real costs of raw material (sewing and harvesting the seed) as well as extraction by farmers and regional producers in order to calculate their real profit margin and set competitive prices.

Originality/value

The research responds to a specific demand by the State of Chiapas to assess the feasibility of its value chain by identifying the activities that do not create value.

Details

Management Research Review, vol. 36 no. 12
Type: Research Article
ISSN: 2040-8269

Keywords

1 – 10 of 38