Selection of material for a specific engineering component, which plays a significant role in its design and proper functioning, is often treated as a multi-criteria decision-making (MCDM) problem where the most suitable material is to be chosen based on a given set of conflicting criteria. For solving these MCDM problems, the designers do not generally know what should be the optimal number of criteria required for arriving at the best decisive action. Those criteria should be independent to each other and their number should usually limit to seven plus or minus two. In this paper, five material selection problems are solved using three common MCDM techniques to demonstrate the effect of number of criteria on the final rankings of the material alternatives. It is interesting to observe that the choices of the best suited materials solely depend on the criterion having the maximum priority value. It is also found that among the three MCDM methods, the ranking performance of VIKOR (Vlse Kriterijumska Optimizacija Kompromisno Resenje) method is the best.

The political costs, bonuses paid to managers, how to use the growth opportunities obtained and their effects on the profitability of companies are the issues that have always been a major of corporations’ concerns. Company exposure to political decisions, its costs and effects on the company's cash flow is very important. Hence, understanding the relationship between variables in a company and how they influence on each other helps management decisions for better opportunities and reduction in political costs, increase cash flow and ultimately increase the profitability of the firms. This survey studies the relationship between the impact of political costs on companies with high free cash flow and low growth opportunity. In this survey, company's assets, sales, income and number of employees are estimated. Then the indexes related to these costs are evaluated based on the tax component, the cost of the sports, personnel costs and relationships among them. Pearson correlation coefficient, regression coefficients and analysis of variance have been used to examine the hypotheses of the survey. The results show that the political cost, high free cash flow and low growth opportunity had negative correlations with each other. In other words, there was a negative relationship between profit and political costs in companies with high free cash flow and low growth opportunity. Moreover, high free cash flow and low growth opportunities had significant effect on the relationship between political costs and benefits in companies listed in Tehran Stock Exchange.

A crucial issue in humanitarian relief operations is vehicle routing because there are many difficulties in roads that people face when a disaster is occurred. In such circumstances, selecting more reliable routes could help rescue team act more efficacious. Therefore, we propose a mathematical model that maximizes the reliability of selected routes in disaster relief routing process using a multiple attribute decision making (MADM) technique. Furthermore, the proposed model minimizes the total cost that imposed to system. For this reason, the model is a multi-objective vehicle routing problem (VRP). The problem considered here is NP-hard and its objective is to find near optimal solutions, rather than optimal ones, using the non-dominated sorting genetic algorithm.

Silicon/glass bi-materials are used in micro-assembly and packaging of micro-electromechanical systems (MEMS) and micro-electronics devices. In this paper, maximum tangential stress (MTS) concept is used for determination of the fracture initiation angles of silicon/ glass bi-material notches. First, the MTS criterion is analytically formulated for a bi-material notch problem. Then, the criterion used for prediction of fracture initiation angles of some experimental data given in literature for silicon/ glass bi-material notches. In addition, the modified MTS (MMTS) criterion, which considers the effect of I-stress, was compared with the MTS criterion and the experimental data. It was shown that MMTS criterion provides more accurate results than the MTS criterion for estimation of the fracture initiation angle.

An efficient and simple protocol of B-enaminones and B-enamino esters synthesis using nickel oxide under ultrasound sonication has been developed. Ultrasound sonication triggers the formation of enaminones under the mild reaction conditions. Nickel oxide was found to be efficient, heterogeneous, moisture stable, robust and recyclable catalyst.

Ranking fuzzy numbers is one of the most important phases in any decision making process in fuzzy environments. In most cases, we deal with fuzzy numbers in the field of evaluating alternatives with fuzzy information or linguistic variables. This paper investigates ranking fuzzy numbers using the concept of preference ratio, introduces the weakness of this method, and proposes a new approach that overcomes the shortcoming of existing method. The proposed approach which is based on the concept of utility function takes the opinion of DM for ranking fuzzy numbers into account.

Stroke is one of the main causes of disability. It affects millions of people worldwide. One symptom of stroke is disabled arm function. Restoration of arm function is necessary to resuming activities of daily living (ADL). Along with traditional rehabilitation techniques, robot-aided therapy has emerged recently. The control schemes of rehabilitation robots are designed for two reasons. First they are designed for passive rehabilitation in which the robot guides the patient & apos; s limb through a predefined path and second for active rehabilitation in which the patient initiates the movement and is partially assisted or resisted by the robotic device. This paper introduces a new robot for shoulder rehabilitation. The Shoulder Rehabilitation System (SRS) has three degrees of freedom (DOFs) for three rotational DOFs of the shoulder but additional translational DOFs of the shoulder are also allowed to avoid discomfort to the patient. A new open circular mechanism is proposed for the third joint that solves the known issues for rehabilitation robots such as long wiring and discomfort associated with closed mechanisms. Lyapunov-based controller with integral action is proposed to guide the robot through a predefined trajectory. Simulation results proved that the proposed controller can track the desired trajectory; reject constant bounded disturbance to the system and is robust due to its nonlinear nature. The proposed controller is designed to be used in passive rehabilitation.

These days, one of primary concerns for residence of big cities is associated with the access on shopping centers. People prefer to live in places, which are close to their works, shopping centers and schools. Local governments also prefer to find the most appropriate places in an attempt to reduce unnecessary travels and traffic jams. In this paper, we present an empirical investigation to determine the most important factors influencing facility location for fruit and vegetable market in city of Tehran, Iran. The study has implemented two methods of analytical hierarchy process (AHP) and factor analysis for the investigation. The implementation of AHP has considered two main criteria including Geographic location of market and market, amenities and existing infrastructures. In terms of Geographic location of market, cost saving and public infrastructure are found to be the most important factors while in terms of market based factors, Space and availability of parking are the most important factors. We also use factor analysis and the results of our survey have indicated that Space and Ease of access were two most important factors, which must be considered for facility location.

Superabsorbent hydrogels based on poly(vinyl alcohol) were prepared by a crosslinking technique using glutaraldehyde as a crosslinker. The hydrogel structure was confirmed using scanning electron microscopy (SEM). Results from SEM observation showed a porous structure with smooth surface morphology of the hydrogel. We have systematically optimized the certain variables of hydrogel synthesis (i.e. the crosslinker concentration, poly(vinyl alcohol) content, time and temperature of crosslinking reaction) to achieve a hydrogel with maximum water absorbency. It was concluded that under the optimized conditions, maximum capacity of swelling in distilled water was equal to 231 g/g. The absorbency under load (AUL) of hydrogels was also measured. In addition, swelling ratio in various salt solutions was determined and the hydrogels exhibited salt-sensitivity properties.

5S is a systematic technique used by organizations come from five Japanese words; Seiri (Sort), Seiton (Set in order), Seiso (Shine), Seiketsu(standardize) and Shitsuke (sustain). This system helps to organize a workplace for efficiency and decrease non value added activities and optimize quality and productivity through monitoring an organized environment. This paper aims to review previous studies about benefits of 5S Implementation and its efficiency in organizations. The results show that 5S is an effective tool for improvement of organizational performance, regardless of organization type, size, its production or its service. Consequently, 5S technique would strongly support the objectives of organization to achieve continuous improvement in performance and productivity.