Nazario García

A Decision-Making Support System on a Products Recovery Management Framework. A Fuzzy Approach:

The considerable amount of uncertainty involved in defining the factors that affect reverse logistics (RL) decision-making and the complex interrelationships between those factors make it rather difficult to decide what recovery policy a business should pursue. This article proposes a fuzzy system that helps in such decision-making and thereby mitigates these difficulties. The knowledge related to the decision is incorporated into the system by means of conditional rules, which serve to provide the ideal recovery policy for each particular case. The model proposed is applied to the analysis of a number of examples and proves to be a versatile tool that provides coherent results. These characteristics could be of critical importance especially in the point of entry into the RL pipeline and in the centralized return centres.

Suitability of a Consensual Fuzzy Inference System to Evaluate Suppliers of Strategic Products

This paper designs a bidding and supplier evaluation model focused on strategic product procurement, and develops their respective evaluation knowledge bases. The model is built using the most relevant variables cited in the reviewed procurement literature and allows to compare two evaluation methods: a factor weighting method (WM) and a fuzzy inference system (FIS). By consulting an expert panel and using a two-tuples symbolic translation system, strong fuzzy partitions for all model variables are built. The method, based on central symmetry, permits to obtain the fuzzy label borders from their cores, which have been previously agreed among experts. The system also allows to agree the fuzzy rules to embed in the FIS. The results show the FIS method’s superiority as it allows to better manage the non-linear behavior and the uncertainty inherent to the supplier evaluation process.

Modeling a System of Public – Private Management of Business Areas

Currently, the management structures of the business areas and further industrial sites respond to inefficient models, regardless if is the Public or Private Sector who assumes that management. So far an ideal formula has not been found to ensure the provision of basic and advanced services. Nor is there any national solid reference of Public Private Partnership in the business areas management. Although this already exists in the Real Estate Industry, its analysis is far from the purpose of this paper. Here it is analyzed the model of the British BID (Business Improvement Districts), very successful in revitalizing urban centers and small businesses, and their possible application in the business areas of Spain. This work includes, based on critical analysis carried out on three experiences in England, the definition of a new mixed formula called Concerted Management Model, that relies on the currently existing Spanish legislation and that fully reflects the spirit of the BID system.

A genetic algorithm approach to a 3D container-loading problem

Standardisation of transport means, such as containers, has a direct impact on the transportation efficiency sought by European transport policies. In this paper, we present a Genetic Algorithm (GA) application to the container-loading problem trying to maximise the cargo volume accommodated in the container whilst ensuring that loading restrictions are met, and thus achieving a reduction in the number of freight to hire and thereby a reduction in costs. We have also developed spatial representation software as aids to assist the container-loading process.

Supply Chain Management: The Systemic Challenge

Practitioners extensively recognize the supply chain as an overall system with growingly complex interdependences. Nevertheless, several studies have pointed out that managers fail to see the whole system, and hence they do not operate consistently to such recognition, but they usually approach the issue from a local optimization perspective. This kind of reductionist solutions create large inefficiencies, which damage the profitability of the various supply chain members. Under these circumstances, we highlight the deployment of the systemic approach as the great challenge of the 21st-century supply chains. This paper develops this idea. Firstly, we explore the concepts of efficiency, flexibility and resilience as core operational goals for supply chains operating under the current global scene. Secondly, we underscore the systemic approach by defining the basic supply chain archetypes underlain by contrary philosophical approaches. Thirdly, we devise a framework based on three strategic axes—education, orchestration, and methodology—from which the systemic challenge must be tackled.

Heuristic Analysis Influence on the Solution of the Vehicle Routing Problem by Means of an Iterated Local Search

The capacitated vehicle routing problem is a common logistic problem in many industries. We present an analysis of the initial solution algorithm and perturbation solution effects on the final quality of an Iterated Local Search (ILS). The main conclusion of the work is that the best results are obtained by the combination of various perturbation methods. The importance of the initial solution is not so clear. Furthermore, in this work, an ILS modification was presented, its main characteristics are the few parameters needed and the quality of its results.

Zoning by k-Means over a Large Data Set

In this paper, for zoning a large set of locations data we apply the k-means clustering algorithm. The results were plotted graphically and were satisfactory, so we conclude that the algorithm is useful despite the size of the data, at least for low data dimensions (latitude, longitude).

Using fuzzy inference systems to improve purchasing process-related decisions

Supplier evaluation and selection processes have strategic aspects and implications in the long run for a company. However a literature review surfaces a high number of variables involved in such processes and the variety of different methodologies to be used. In order to overcome the drawbacks present in some methodologies we propose a fuzzy decision system that considers the most significant variables and allows to evaluate and compare new suppliers to historical ones as well as to update the list of the certified ones. This model not only strengthens the operating of the model but also eases the understanding of the process-related knowledge. A survey test is used for validation purposes.

Efectos de la implicación en actividades de recuperación de valor sobre la función de aprovisionamientos

The present work analyzes the impact in the traditional management of the chain of supply as consequence of the incorporation of the returns in the daily activity of the companies. More specifically, we investigated the effects that take place in the functional area of the provisionings putting emphasis in five of the more relevant aspects. By means of an exploratory design of investigation, we analyzed the behavior of two companies manufacturers of the electronic sector and of goods of equipment. The belonging to different sectors allow us to identify differentiated attitudes on this type of processes. The above mentioned attitudes are tied to restrictions derived from the nature of product, of the type of business, of the process or of the market.

The competitive approach to purchasing in the metallurgical industry in the autonomous region of Asturias (Spain)

Abstract A general analysis of the literature on purchasing highlights a series of management changes that have occurred which constitute what we consider to be a competitive approach to the whole business of Purchasing. We have selected what seem to us to be the most significant basic tendencies from within this general approach to carry out research to measure the extent to which this new approach is being implemented in the metallurgical industry in the Autonomous Region of Asturias (Spain). The hypotheses that define the competitive approach to purchasing are first defined, and are then confirmed or rejected, depending on the preponderant behaviour of companies in the industrial sector. Results lead to the conclusion that the industrial sector in question is not completely following the tendencies defined in the research.