Every day in workplaces, continues events occur that cause death and injury. These accidents usually happen because of lack of exploring the potential hazards and lack of training of employees. Hence, with exploring and evaluating the hazards of workplace and utilizing the suitable procedures, it is possible to prevent from many of these hazardous incidents. Exploring, evaluating and controlling the potential hazards have been the initial stages of scientific safety assurance in every system. Preliminary hazard analyzing is the first effort in analyzing hazards. In this method, usual hazards in sighted job are explored, using the usual hazards table for developing the basis of PHA, the PHA checklist is prepared and at last the PHA table completed and the appropriate suggestions are given. In this paper, we present an implementation of PHA method in one of industries located in city of Tehran, Iran. The proposed study uses 15 explored hazards, where 2 are unacceptable, 9 are undesirable and 4 are acceptable with need of revisal. By eliminating and reducing each hazards risk, some controlling solutions are suggested. The most important of these solutions are utilizing and using the regulations of the welding with electrical archer.

This paper presents an empirical study on measuring the effects of fiscal policy in terms of government spending on private consumption in both recession and booms over the period of 1965-2010. The proposed study uses Hodric-Prescott filter to find the cycle of recessions and booms. Then, we use autoregressive distributed lag model to estimate the changes. The results of this survey indicate that, in long term, an increase on government expenditures normally impacts private sector positively in both recessions and booms. The impact in short terms is positive during the recessions but during the booming session, there is no meaningful relationship between government spending and private spending.

Quality Function Deployment (QFD) as one of the quality engineering methods; originates from market study and product or service customers identification, where by determining their needs; tries to involve them in all stages of product or service development. This study uses QFD method to apply customers’ criteria in production of Coach Plasma in Mashhad`s Sahateb Company. Coach Plasma is used for healthy bloodletting. The proposed study of this paper designed and distributed a questionnaire, which includes identification & determination of customers’ needs and investigation of their satisfaction of manufactured products, while looking for technical and engineering characteristics related to their needs. The Coach Plasma costumers are categorized into two groups of local and external customers. Data collection was done based on available documents, experts opinions, structured interview with managers and questionnaire. Customers’ needs were studied in QFD teams. Collecting essential information such as needs importance degree and competitive benchmarking of customer`s needs, the weight of each need has been evaluated. In this research, House of Quality was used from first matrix of QFD leading to estimation of engineering & technical characteristics in order to enter to the quality deployment matrix. Take a look at obtained results, we could mention the role of each of these external factors in satisfaction of Sahateb Company customers and technical characteristics of the company in providing these factors and the prioritization of the customer & apos; s needs.

This study examines the relationship between earnings management and information asymmetry based on some companies listed in Tehran Stock Exchange over the period of 2005-2010. The study only uses qualified samples by taking into account all limitations and necessary criteria. Based on the results of this survey, we can conclude that there is not a significant relationship between earning management and information asymmetry in Tehran Stock Exchange. There is also not a significant relationship between low or high earning management and information asymmetry. Estimated dividend announcement has information content and it can influence on information asymmetry. Finally, in Tehran Stock Exchange, there is information asymmetry and after dividend announcement, its value is more than before.

Ranking insurance firms plays an important role on choosing the most appropriate company for receiving appropriate services especially long term insurances such as life insurances. The proposed model of this paper uses two well-known methods of CAMELS and RBC to rank 18 active private and governmental insurance firms in Iran over the period of 2009-2011. The results of Spearman test imply that there is no meaningful difference between these two methods for year 2010 and year 2011 and according to Freedman test, there is not meaningful difference between these two methods in any three years of 2009, 2010 and 2011. In summary, we can conclude that the results of both methods could be used in practice.

Autoregressive moving average (ARMA) process and dynamic neural networks namely the nonlinear autoregressive moving average with exogenous inputs (NARX) are compared by evaluating their ability to predict financial time series; for instance the S & P500 returns. Two classes of ARMA are considered. The first one is the standard ARMA model which is a linear static system. The second one uses Kalman filter (KF) to estimate and predict ARMA coefficients. This model is a linear dynamic system. The forecasting ability of each system is evaluated by means of mean absolute error (MAE) and mean absolute deviation (MAD) statistics. Simulation results indicate that the ARMA-KF system performs better than the standard ARMA alone. Thus, introducing dynamics into the ARMA process improves the forecasting accuracy. In addition, the ARMA-KF outperformed the NARX. This result may suggest that the linear component found in the S & P500 return series is more dominant than the nonlinear part. In sum, we conclude that introducing dynamics into the ARMA process provides an effective system for S & P500 time series prediction.

In the recent years, social media have developed significantly and their usages have become main activities of internet users. The proposed study of this paper considers the effects of personal characteristics such as age, gender and marital status on social media. The study designs a questionnaire and distributes 385 questionnaires among students who are enrolled in different educational levels in governmental university named Allameh Tabatabayi university located in Tehran, Iran during the year of 2011. Because of abnormality of data, non-parametric test were used. In this research, we studied the effects of demographic variables on success of social media. The results showed that success of social media is more important among female students. Marriage situation shows that social media success variable is more important among married than single ones and, finally, this variable is more important among older people.

Today & apos; s methodologies for data quality assessment and improvement are considerably aimed at reducing costs. Data quality comprises different dimensions, each having certain methods and techniques to assess and improve data quality. One of the most controversial dimensions is data believability in which less attention has been paid by scholars and researchers, because of its ambiguous nature. This is categorized under the "intrinsic data quality" dimensions. The current paper offers a precise and comprehensive definition of such quality dimension, and provides some parameters to understand it. In order to calculate these parameters, furthermore, different methods are discussed.

Effective planning and management of workforce for new product development (NPD) projects is a great challenge to many organisations, especially in the presence of engineering changes during the product development process. The management objective in effective workforce management is to recruit, develop and deploy the right people at the right place at the right time so as to fulfill organizational objectives. In this paper, we propose a dynamic simulation model to address the workforce management problem in a typical NPD project consisting of design, prototyping, and production phases. We assume that workforce demand is a function of project work remaining and the current available skill pool. System dynamics simulation concepts are used to capture the causality relationships and feedback loops in the workforce system from a systems thinking. The evaluation of system dynamics simulation reveals the dynamic behaviour in NPD workforce management systems and shows how adaptive dynamic recruitment and training decisions can effectively balance the workforce system during the NPD process.

In today’s global scenario of intense competition and environmental uncertainty flexibility in supply chain has an important role to play for the existence of any supply chain business. A need to be responsive to the constantly changing market scenario and cater to the customer needs, a certain degree of flexibility is required, which requires the coordination of many plants to produce and deliver goods to customers located in different places, and suppliers, which provide each plant with the required components. This paper intends to measure the degree of flexibility required for a two stage supply chain and assessing both the supplier flexibility and the assembler flexibility. In this paper, nine configurations of the SC are considered resulting from the combination of the three degrees of supplier and manufacturer flexibility, i.e. no flexibility, limited flexibility and total flexibility, respectively. Simulation model representing the different flexibility configurations are evaluated and the performance of each configuration analyzed to determine the flexibility configuration suitable to a supply chain. In particular the performance analysis of lead time, work-in-process, service level and cost are measured to determine the suitable flexibility.