Laura Guitart Tarrés

Optimization of replacement stocks using a maintenance programme derived from reliability studies of production systems

This paper is the outcome of a study carried out in a nine‐cell flexible manufacturing unit which produces components for Diesel engine injection pumps. The study involved the monitoring and recording of the various types of failure which led to interruptions in production. The objective of the study was to design a maintenance system for the optimal management of replacement stocks, both from the technical and economic point of view. The design of this programme was based on matching a given statistical distribution (Weibull’s distribution, exponential, normal, log‐normal, or gamma) to the time between failures. By means of this fit, the basic system parameters were determined: average lifetime, failure rate, mean time between failures, mean time between inspections. Knowledge of these variables permits us to determine the frequency of inspections in relation to the level of reliability we require of the system. This information also enables us to establish a programme to determine which elements require inspection, the frequency of these inspections and the operations that need to be carried out.

El perfil de las filiales industriales de multinacionales extranjeras ubicadas en España

This work presents a study of the presence of foreign multinationals in the Spanish industry, consisting of a descriptive analysis to determine its relevance on the total of the industrial sector. Moreover, to define the profile of these companies we carry out a classification according to their strategic behavior using variance and contingency tables analysis. The starting point of this work has been the preparation of a database from diverse kind of information sources, that has allowed to identify the companies with foreign capital participation in the Spanish industrial sector. The main contribution of this paper is the identification of three types of subsidiaries: a first group that only operates in the domestic environment; a second group (the most numerous) that carries out export and import activities and have some participated companies abroad and, finally, a third group of subisidiaries (of certain importance in the multinational group) that develops a very intense external activity.

El papel del entorno en la localización de actividades de I+D en las filiales de multinacionales extranjeras

Resumen La internacionalizacion de actividades de I+D en paises extranjeros distintos del de origen de las multinacionales es una dificil decision, y el entorno local es uno de los elementos fundamentales para su localizacion. A partir de un estudio de casos y tomando como referencia siete filiales con centros de investigacion de excelencia en Espana, se concluye que los factores relacionados con la oferta tecnologica tienen mayor poder de atraccion que los de demanda de mercado. Sin embargo, se constata que el entorno espanol resulta mas atractivo por el lado de los factores de demanda que por el de oferta y, por lo tanto, se situa en una posicion intermedia en la atraccion de inversion directa en actividades de I+D en el exterior.