China’s hog production is undergoing a great transformation due to the soaring demand and changing raising system. Regarding the essential role of pork in Chinese diet, a systematic analysis on the productivity and efficiency of hog production can provide significant implications for policy makers. This paper investigates the productivity and efficiency of hog production and determinants of tec...

The techniques and methods of developing cost models for respirators are discussed. Models are developed and implemented in this study for nineteen types of respirators in two major classes (air-purifying and supplied-air) and one LEV system. One respirator model is selected for detailed discussion from among the twenty models. The technical cost method is used in constructing the cost models f...

In this paper a gas turbine power plant including air preheater (recuperator), heat recovery steam generator and air cooler system was modeled. Eight parameters were selected as the design variables.  Fast and elitist non-dominated sorting genetic algorithm (NSGA-II) was applied (to maximize the exergy efficiency and to minimize the total cost rate) for the mentioned cogeneration system. Th...

This paper estimates a translog stochastic frontier production function in the analysis of all 48 contiguous U.S. states in the period 1970-1983, to attempt to measure and explain changes in technical efficiency. The model allows technical inefficiency to vary over time, and inefficiency effects to be a function of a set of explanatory variables in which the level and composition of public capi...

awardness about structure of production technology and its characteristics is a usefull tool for planning in agricultural sector. in this regard, this study aims to determine some effective parameters of structure of production technology in rain fed barley production. before estimating these parameters, we examine the aggregation consistency condition for barley fields using the mean scaling t...