Conventional data envelopment analysis (DEA) models are used to measure efficiency score of production systems when they are considered as black boxes and their internal relationship is ignored. This paper deals with a common special case of network systems which is called multi-stage production system and can be generalized to many organizations. A multi stage production system has some stages...

the effect of 6-month water storage on microleakage of two-component self-etch adhesive systems      dr. mohammadibasir m .,1 dr. seyed tabaii e .2   1 assistant professor, department of operative dentistry , school of dentistry, shahed university. tehran , iran.   2 dentist.     (received 5 dec, 2010 accepted 14 april, 2011)     abstract     background and aim : simplification of the self-etch...

many studies have been conducted to determine the efficiency of two-stage network structures in the recent years. the two-stage network with additional inputs to the second stage, in which the second stage is independent of the first stage are one of these structures. thus, there is a need for a model capable of calculating the efficiency of two-stage structures as well as efficiency of each st...

As a non-parametric method of relative efficient measurement of a group of decision-making units (〖DMU〗_s), Data Envelopment Analysis (DEA) is one of the most important tools in efficiency computation. One of the main concerns dealt with in DEA is dealing with return to scale in two-stage processes in which, produced outputs of the first stage inputs are used as inputs for the second stage. The...

In this work, single-stage and two-stage tubular solid oxide fuel cell (SOFC)/gas turbine hybrid cycles are comparatively examined from the energy and exergy viewpoints. For this purpose, mass, energy and exergy balances are applied to all components of the cycles. The behavior of tubular solid oxide fuel cell modeled in this study is validated with the experimental test data of tubular SOFC de...

 Abstract Background: Rehabilitation of facial paralysis is one of the greatest challenges faced by reconstructive surgeons today. The traditional method for treatment of patients with facial palsy is the two-stage free gracilis flap which has a long latency period of between the two stages of surgery. Methods: In this paper, we prospectively compared the results of the one-stage gracilis flap ...

this study is the result of an attempt to investigate the differences between the persian translated drama text (page) of each english drama text with its performance on the stage (stage) in iran. in other words, the present researchers tried to find the implemented changes in page which make it real on the stage in the target language and culture in order to show that in drama translating and ...