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In a system, prediction of remaining useful lifetime (RUL) of servicing before reaching to a specified breakdown threshold is a very important practical issue, and research in this field is still regarded as an appreciated research gap. Operational environment of an equipment is not constant and changes regarding to stresses and shocks. These random environmental factors accelerate system deterioration by affecting on the level or rate of degradation path. The present study focuses on providing a practical operational guideline to estimate the RUL of a system with general degradation path after receiving a shock which only affects on the degradation level. Due to exact estimation of the shock arrival times and measuring the magnitudes of future shocks to investigate shock effects on RUL is almost impossible in the real world and laborious in practice, in this research a new procedure based on total defect size monitored in the constant inspection periods and Accelerated Factor (AF) is proposed to analyze RUL of the system. A Micro-Electro-Mechanical system (MEMS) is used as an example and the results show the applicability of the proposed approach.

Allocation of human resource properly can have an effective role in the hospital emergency departments cost performance. This research has been conducted to provide the optimal solution on staff leveling for emergency department of hospitals.
This research is an applied research and deploys from analytic analysis. The population of study include patients referred to a given emergency department on Imam Reza Hospital in Tabriz at a period of three months in 1393. After analyzing the current patient workflow, required data concerning the patients’ inter-arrival time, cycle times in different stations gathered for 900 patients during three weeks. Based on such data, simulation models designed using the Arena software features and finally the model verified and validated. Then proposed linear programming model based on minimizing patients’ average stay time, helped to calculate optimum staff leveling.
Result of sensitivity analysis on DTDT, show that if operational budget of emergency department increased 10%, 20%, 30%; The LOS leads to 359,337,308 minutes. In the lower budget, this correlation is apparent and significant.
Simulation results revealed that increasing on the number of physicist has the most priority on extra investment. Also, the proposed simulation model helped the operating managers to get more sense on the effects of the relevant controllable factors to total efficiency on the emergency department; in simulated framework, without operational experience, examine intended scenarios and comparing results then select best solutions.

Developing a conceptual model to analyze effective costs in logistics process is one of the aims of the present article. By Reliance of literature review in the field of logistics and by using the results derived from the carried out case studies in small and medium-sized food and automotive enterprises, the effects of targeted subsidies plan on Logistics costs and solutions to costs reduction are studied. In this paper, combined qualitative and quantitative methods are used, qualitative methods such as interviews and quantitative methods such as Analytical Hierarchy Process (AHP) and statistical analysis.The result shows that at the macro level logistics costs are divided into seven categories: Transportation costs, Inventory carrying costs, Warehouse costs, Order Processing and Information Systems costs, Handling costs, Lot quantity costs and Customer service costs. Based on the type of industry, some costs are more important than other costs. Applying the Analytical Hierarchy Process on logistic costs shows that transportation and distribution costs beside capital costs are the largest in the logistics costs. Comparison of logistics costs before and after the implementation of the targeted subsidies plan shows that costs at Pegah Company has increased by 1.48% and at Zar-Fanar Company 2.42% in sales revenue. Increasing energy prices and high storage due to varying business conditions are the causes. Developing logistics cost management system beside controlling and optimizing the time and economical orders could act as appropriate solutions for the two companies to reduce their own logistics costs. The relationship between solutions and cost reduction are reviewed by using a nonparametric test (Binomial) and approved solutions are prioritized by using the Friedman test.

color, as an important quality of objects, can alter in- dividuals’ emotions and influence automobile selec- tion and sales. A review of previous research literature in- dicates that color affects human life unconsciously and thr- ough cultural factors. This study compared that ratios of ve- hicle colors manufactured in United States in 2005 and 2006 with similar vehicles at Iran-Khodro in the same period. Re- sults showed that although silver is the most manufactured vehicle color in both countries, its production ratio is sig- nificantly higher in Iran. More blue, black, red and beige ve- hicles were manufactured in the U. S. A than in Iran While Iran manufactured more green and grey vehicles than the U. S. A. The results are discussed based on cultural and psy- chological differences plus economic limitations.