Quantifying cartilage contact stress is paramount to understanding hip osteoarthritis. Discrete element analysis (DEA) is a computationally efficient method to estimate cartilage contact stresses. Previous applications of DEA have underestimated cartilage stresses and yielded unrealistic contact patterns because they assumed constant cartilage thickness and/or concentric joint geometry. The stu...

This article computes the energy productivity changes of regions in Japan using total-factor frameworks based on data envelopment analysis (DEA). Since the traditional DEA-Malmquist index cannot analyze changes in single-factor productivity changes under the total-factor framework, we apply a new index proposed by Hu and Chang [2009. Total-factor energy productivity growth of regions in China. ...

Diethanolamine (DEA) is a widely used ingredient in many consumer products and in a number of industrial applications. It has been previously reported that dermal administration of DEA to mice diminished hepatic stores of choline and altered brain development in the fetus. The aim of this study was to use mouse neural precursor cells in vitro to assess the mechanism underlying the effects of DE...

The deprotonation kinetics of the DEA--C02 and the DIPA-COZ zwitterions have been studied in aqueous blends of an&es at 298 K. Amine mixtures investigated were: DEA-TEA, DEA-MDEA. DEL-DMMEA, DEA-DEMEA, DIPA-TEA, DIPA-MDEA, DIPA-DMME~ DIPA-DEMEA. FOG each blend the zwitterion deprotonation constant of the additonal base present in solution (i.e. the tertiary amine) was determined. The observed d...

Data envelopment analysis (DEA) is a method frequently used to evaluate relative firm performance. However, high values in a few indicators can lead to a company being regarded as ‘efficient’, despite valuing poorly in other essential indicators. The Inefficiency Countervailed DEA (IC-DEA) method is thus developed. The method first defines an inefficient frontier using the proposed Reverse DEA ...

This paper concentrates on methods for comparing activity units found relatively efficient by data envelopment analysis (DEA). The use of the basic DEA models does not provide direct information regarding the performance of such units. The paper provides a systematic framework of alternative ways for ranking DEA-efficient units. The framework contains criteria derived as by-products of the basi...

Some specific geometric data envelopment analysis (DEA) models are well known to the researchers in DEA through so-called multiplicative or log-linear efficiency models. Valuable properties of these models were noted by several authors but the models still remain somewhat obscure and rarely used in practice. The purpose of this paper is to show from a mathematical perspective where the geometri...