نشریه مدیریت راهبردی در سیستم های صنعتی
پیاپی 17 (پاییز 1390)

The critical chain is a novel approach in the domain of project managementwhich has been developed to eliminate projects unfavorable impacts and theirreasons. Also, it is used to increase resources performance and to utilizerestrictions of project system. To secure project against probable disturbancestime buffers were installed in different areas based on this approach. Thus,tensions of uncritical activities were kept to be transferred to critical chain andtensions of critical chain activities were prevented as well to be transmitted to project delivery time. In the present paper, a method to determine buffers size in the domain of critical chain was presented. The method fortified with such main characteristics as applying experts ideas throughout the work steps, as well as simple implementing process. Even though, the concepts proposed in this method are close to Pert method, the distribution function of activities time probability in the method was obtained according to experts ideas. Finally, the critical chain was conducted for designing, constructing, and installing of a steel structure in Suliran Company to assess the suggested method. Buffers size were estimated using two recognized methods in literatures, Cut and Paste (C&P) method, Root Square Error (RSE) method and the proposed method. Comparing with two mentioned methods, the presented method, as obtained results display, generates buffers with more protection against project's probable delays.

The present paper aims at investigating the relationship between entrepreneurship and business performance. The research sample consisted of 214 managers selected randomly from Arak city. Using Entrepreneurship Inventory data and Business Performance Checklist, the data of the both mentioned means were analyzed. The results obtained from Pearson correlation showed that entrepreneurship and its components are related to business performance in managers of productive units (P <0.05). The result of multiple regression showed that such components as need for achievement and autonomy creativity, risk taking, and conserving had significant contribute in prediction of business performance. Consequently, the results in general indicated that high levels of entrepreneurship can increase business performance in managers of productive units.

Determining the leanness of different organizations is one of the key factors of progressinto establishing a system without wastes and maximizing productivity in whole supply chain management. Lean manufacturing as a management philosophy concentrates on eradicating wastes in whole value chain of a product. Using the improved dimensional analysis and its conversion to the standard form, this paper aims at identifying and analyzing 6 main factors and 35 sub-factors. Also, we used multi criteria decision making techniques according to the direct role of experts and differentiation of their votes to the specified alternatives. Analytic hierarchical process and Fuzzy-Topsis were used to define the linguistic weights of experts in our model. Additionally, linguistic values were parameterized by triangular fuzzy numbers to optimizing the decision making methods and avoid vagueness. The results show that the degree of adaptability of Rose Fire Place Company with lean manufacturing factors and characteristics is 0.52. Also, the results indicate the distance of various parts of the production managementwith respect to lean manufacturing. Finally, this approach is recommended for being used in every assembly industries.

Iran's IPR system, similar to those developing countries, is reactive. The aim of this research is describing the actual deficiencies in Iran's IPR system. Also, the investigation aims at identifying the roots and reasons of the reaction and the effective internal factors. The present study which is a library research, reviews experts opinions and relevant indexes using depict method. At first, backgrounds of the global economy and different approaches of developing and developed countries in the IPR system are surveyed according to published articles. Then, effective global reasons in present situation of Iran and also relevant to internal and external factors are identified. So, three kinds of factors and reasons identified according to this classification are as follows: (a) global fields and weak role of developing countries in innovation; (b) the relevant factors with weak performance of Iran's National Innovation System (NIS); and (c) structural weakness and disharmony in performance of policy and executive agent in Iran's IPR system. Some of the factors are related to internal agent weakness and the others are related to international issues such as universal challenge between developing and developed countries. IPR system, as one of the important elements of NIS is a determining factor in the development trajectory of any country. The following subjects need attention order to revising Iran's IPR system: (a) consideration of IPR system performance in NIS (b) coordination of IPR system ability and development level of the country.

Information technology enables knowledge management to integrate management's thoughts to computer applications and various computations in order to improve systems. Whereas in most organizations specially telecommunication this process is not systematic. This paper is using fuzzy analytic hierarchical process to study information technology roles in designing and implementing knowledge management in telecommunication organization in systematic insight. Since various and multiple dimensions involved in the research, a decision-making approach is required to evaluate complicated issues. Fuzzy analytic hierarchical process method enables eliminating and handling the data uncertainty and ambiguity. The research results show that communicating and participating technologies are important motives in designing and implementing knowledge management systems. Hence, collaborative intranets and the interactions between experts and knowledge workers are core indicators which affects information technology role in designing and implementing knowledge management systems.

Nowadays, Iranian designers, contractors and government agents encounter with greatdeal of problems in their construction projects. The main reasons of the occurringproblems can be incorrect designing, perplexity of technology, variety of expertiseneeded, great deal of activities and number of stakeholders engaged. For these reasons,the project are not usually completed in due time and in the mount of the predicted costscope. Value engineering (VE) is a problem solving method (PSM) based on thesystematic job plan and creativity. VE aims at reviewing the project and identifying theopportunity of saving project cost and time. Regretfully, in the same cases, VE is not adjusted with needs, specifications and limits of project construction and that cannot remove the problems. This paper can use concepts and techniques of total quality management (tqm) for developed VE structure and increase its effect on construction project. To create a new model, first, VE, TQM and problem of construction project were reviewed. Next, using other accomplished researches in this field of study, development potentials of VE was identified. Finally, a new model was issued based on the studies.

Bus system is one of the public transportation system subsets and it is the most predominant types of public transportations in developing countries. Researches show that, bus dwell time at bus stop is an important part of the total traveling time which can take nearly 26 percent of total commuting time. Selecting process factors are of the commonly used components in bus dwell time modeling at bus stop which are less considered by scholars. In this study, the affecting parameters are boarding and alighting passengers, number of standee ones on a bus, fare payment methods and number of passenger that don t know the rout. The used data in this study is obtained from number of regular route bus stop at Abadan city which were taken by SPSS software. Creating the data bank, the Linear Polynomial Regression Models concerning investigation of the effects of variables on the passenger's wait time are estimated. Since the traffic in Abadan is not so slow and streets do not suffer from the of lack of high traffic load, studying the bus dwell time at bus stops seems required to proper urban traffic planning and decision making, make schedules of bus lines, simulate bus routes and ultimately to develop and improve the public transportation system.

This survey has been done among companies listed in the cement industry in Tehran Stock Exchange during eight years from 1380 to1388. The paper studies the effect of simultaneous use of financial ratios and growth rates on future stock returns which is proven unusual. The data has been collected by using the new software named: Rahavard Novin. The results are based on the after event method and using F and T tests and linear regression statistical analysis. The results show that the hypothesis has not been confirmed yet. That is, the use of financial ratios and growth rates do not affect future abnormal stock returns simultaneously Using stepwise regression test, the final model was driven. Thus, only the operational ratios do not have simultaneous effects on use of financial ratios. Finally, the results obtained from the overall test on the research hypotheses do not confirm the simultaneous impact of the financial ratios on future abnormal stock returns. However, the items in the financial statements reflect the accrual impact of items of financial statements on the process of economic decision making, the influence of the information content of all items is not the same. In other words, liquidity ratios have the highest effect and other ratios like profitability, investment and operational ratios reportedly have high effects on the abnormal stock returns.