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...

Lean manufacturing is a systematic approach to identifying and eliminating wastes (non-value added activities) through continuous improvement by conveying the product at the pull of the customer in pursuit of production. In a more basic term, more value with less work. Since lean manufacturing eliminates many of the problems associated with poor production scheduling and line balancing, lean ma...

the first motive for the determination and evaluation of an energy productionsystem is the need to change. such system is dynamic in nature and is influenced bymany factors such as age and physiological status of individual sheep or goat, quantityand quality of available feed and environment including the management systems.traditional pastoral resource assessments do not always account for the...

Molecular farming technology offers a unique advantage that almost any protein can be produced economically and safely under very controlled conditions. Besides traditional production systems, such as bacteria, yeasts, insects and mammal cell lines, plants can now be used to produce eukaryotic recombinant proteins, especially therapeutic ones. Their advantages as hosts for protein production in...

Production planning and control (PPC) systems have to deal with rising complexity and dynamics. The complexity of planning tasks is due to some existing multiple variables and dynamic factors derived from uncertainties surrounding the PPC. Although literatures on exact scheduling algorithms, simulation approaches, and heuristic methods are extensive in production planning, they seem to be ineff...

This paper considers the comparison of two ðs; SÞ production inventory systems with retrials of unsatisfied customers. The time for producing and adding each item to the inventory is exponentially distributed with rate b. However, a production rate ab higher than b is used at the beginning of the production. The higher production rate will reduce customers’ loss when inventory level appro...

Due to the reduction of renewable energy resources such as fossil fuels, the energy crisis is one of the most critical issues in today’s world. The application of these resources brings about many environmentalpollutionsthatleadtoglobalwarming. Therefore,variouscountrieshaveattemptedto reducepotentialdamageanduserenewableenergiesbytheintroductionandpromotionofrenewable energies as an essential ...

it is expected that residential units may replace   traditional heat and power production systems with cogeneration ones. among the different cogeneration systems, fuel cell based systems are a suitable choice due to their high efficiency, high power density, low emission and low noise. in this paper, a cogeneration system based on solid oxide fuel cells is examined. the system, including the f...

environmental optimizing of pest management strategies and improving theirs trends towards minimum environmental risks programs is a matter of considerable concern of food scientists particularly in developing countries. this study evaluates the environmental impacts of pesticides consumption based on environmental impact quotient (eiq) model in different sugar beet (beta vulgaris l.) productio...