Search results for "efficiency"

Reverse electrodialysis heat engine for sustainable power production

2017

Abstract Reverse Electrodialysis Heat Engine (REDHE) is a promising technology to convert waste heat at temperatures lower than 100 °C into electric power. In the present work an overview of the possible regeneration methods is presented and the technological challenges for the development of the RED Heat Engine (REDHE) are identified. The potential of this power production cycle was investigated through a simplified mathematical model. In the first part of the work, several salts were singularly modelled as possible solutes in aqueous solutions feeding the RED unit and the corresponding optimal conditions were recognized via an optimization study. In the second part, three different RED He…

On the Efficiency of Affine Invariant Multivariate Rank Tests

1998

AbstractIn this paper the asymptotic Pitman efficiencies of the affine invariant multivariate analogues of the rank tests based on the generalized median of Oja are considered. Formulae for asymptotic relative efficiencies are found and, under multivariate normal and multivariatetdistributions, relative efficiencies with respect to Hotelling'sT2test are calculated.

Evaluating the Reform of Healthcare System in Sicily: variations of efficiency and appropriateness between 2008 and 2010

2022


 
 Background. Sicilian government has developed a very ambitious Reform through the Regional Law n. 5 (14th April 2009). Hospitals were requested to ensure the quality of care through monitoring of appropriateness and quality of service. The aim of this study was to assess variations of efficiency and organizational appropriateness of healthcare delivery before and after this Reform and to show patterns associated to different types of healthcare delivery organizations.
 Methods. This study was based on repeated cross-sectional data for 118 (out of 129) short-term, acute-care, non teaching-and-research Sicilian hospitals, in 2008 and 2010. Congestion and slacks analysis was…

Qualité et efficience de l'école primaire française : éléments de comparaisons spatiales et temporelles

2008

08001 - 20 p.; Document de travail de l'IREDU 2008-01; L'objectif principal de ce texte est de présenter des éléments factuels sur les résultats de l'école primaire française. Notre réflexion portera sur deux dimensions complémentaires, à savoir la qualité et l'efficience, celles-ci seront examinées dans une double perspective comparative (temporelle et spatiale). Dans une première partie, nous mobiliserons les données des enquêtes internationales pour apprécier les résultats des élèves français et leur évolution dans le temps sur ces 15 dernières années. La seconde partie sera consacrée aux coûts de l'enseignement primaire et plusieurs aspects seront abordés. Dans un premier temps, l'évolu…

Travail des élèves et performance scolaire

2010

National audience; Le rendement scolaire du travail scolaire, exprimé par le rapport entre le score à une évaluation internationale et le temps de travail total des élèves, varie beaucoup d'un pays à l'autre. les pays où les élèves déclarent travailler le plus, qui sont aussi les pays où la religiosité est la plus forte, sont ceux où les scores sont les plus faibles. Une part de ce constat, qu'il est impossible de déterminer précisément, peut cependant s'expliquer par un biais dans les déclarations des élèves. Entre élèves au sein des pays, le temps de travail varie plus ou moins selon le pays, et de façon plus ou moins liée au score des élèves d'une part, à leur héritage social d'autre par…

Technical efficiency and the vertical boundaries of the firm: theory and evidence

2013

This article provides a theoretical and empirical analysis of the relationship between firms’ technical efficiency and the vertical organization of production. Technical inefficiency is explicitly introduced as the source of firms’ heterogeneity in a Bertrand–Nash model of industry competition: the main prediction of the model is that the most efficient firms choose vertical integrated structures and the less-efficient ones choose disintegrated structures. The empirical part of the article rests on a stochastic frontier analysis (SFA) in a sample of about 400 Italian machine tool (MT) builders, and the result supports the prediction of the theoretical model.

Evolución de la eficiencia técnica de la industria textil española en el periodo 1995-2005. Análisis mediante un modelo frontera estocástica*

2021

La industria textil española, con un peso relativo importante en la manufactura, se encuentra sumida en una profunda crisis como consecuencia de la cada vez más agresiva e intensa competencia ejercida por los países productores de bajo coste. Si bien la eficiencia no agota el conjunto de estrategias para ser competitivo, la presencia de competidores induce a su búsqueda (Porter, 1990). En este trabajo se examina la evolución de la eficiencia técnica del textil español. Con tal finalidad, para el periodo 1995-2005 y cada uno de los siete grupos de actividad en que puede subdividirse la industria textil, se estima una frontera de producción estocástica de tipo translog. Los resultados empíric…

2002

This paper analyses the effects of partially revocable endogenous commitments of a seller in a negotiation with a deadline. In particular, we examine when commitment is a source of strength, a source of inefficiency and when it does not affect the bargaining outcome at all. We show that when commitment possesses a minimum amount of irrevocability this crucially determines the bargaining outcome. In the bilateral bargaining case, commitment becomes a source of inefficiency since it causes a deadline effect. In the choice of partner framework, however, the deadline effect disappears and there is an immediate agreement and, moreover, commitment becomes a source of strength since it increases t…

An integrated methodological approach for optimising complex systems subjected to predictive maintenance

2021

Abstract The present paper addresses the relevant topic of maintenance management, widely recognised as a fundamental issue involving complex engineering systems and leading companies towards the optimisation of their assets while pursuing cost efficiency. With this regard, our research aims to provide companies with a hybrid methodological approach based on Multi-Criteria Decision-Making (MCDM) capable to deal with the main failures potentially involving complex systems subjected to predictive maintenance. Such an approach is going to be integrated within the framework of traditional Failure Mode Effects and Criticality Analysis (FMECA), whose strengths and weaknesses are considered. In pa…

The Economic Impact of Restricted Water Supply: a Computable General Equilibrium Analysis

2007

Water problems are typically studied at the level of the river catchment. About 70% of all water is used for agriculture, and agricultural products are traded internationally. A full understanding of water use is impossible without understanding the international market for food and related products, such as textiles. The water embedded in commodities is called virtual water. Based on a general equilibrium model, we offer a method for investigating the role of water resources and water scarcity in the context of international trade. We run five alternative scenarios, analyzing the effects of water scarcity due to reduced availability of groundwater. This can be a consequence of physical con…