75 research outputs found
Perceptions of Safety Climate in Construction Projects between Workers and Managers/Supervisors in the Developing Country of Iran
What are the different perceptions on safety climate (SC) by workers and managers/supervisors engaged in the construction industry of developing countries? Reconciling these two differing views is pivotal for mitigating and avoiding both the injured and fatal accidents in the construction industry, especially in those developing countries where safety conditions are poor and unpredictable, and safety measures are inadequate in most cases. To answer this research question, the collective perceptions of 118 construction workers and 123 managers/supervisors on the SC in construction projects in Iran were gleaned and investigated. In particular, these perceptions were initially collected by two different empirical surveys validated by a sample of university professors and construction managers and then analyzed through the Kaiser-Meyer-Olkin (KMO) test and Bartlettâs test of sphericity under factor analysis, together with a one-sample t-test. Results indicated that âworkersâ attitudes and perceptionsâ, âsafety knowledge and trainingâ, âworking relationships and roles of colleaguesâ, and âworkersâ risk perceptionsâ are important categories of SC factors perceived by construction workers, whereas âsafety rules and management practicesâ is the essential category of SC factors discerned by managers/supervisors. The difference in perceptions between workers and managers/supervisors is considered to be beneficial for an overall understanding of SC in general and for developing countries in particular. Moreover, a series of effective suggestions for improving SC in the construction industry of developing countries are provided with reference to each category. The views of SC factors are reinforced as a social process combining the synergies of workers and managers/supervisors, as well as proper safety training to be pushed forward as an essential activity that should be incorporated in human resources development of construction organizations so as to improve the existing level of SC, leading to fewer accidents at the industry level
An integrated MCDM approach to evaluate public transportation systems in Tehran
Public transportation is one of the most important systems in transportation, especially in big and crowded cities. As a result, evaluation of public transportation systems is a strategic decision-making problem for both private and public sections. In this paper, the problem of public transportation passengers in Tehran is addressed and their satisfaction levels are assessed by using passenger satisfaction survey. An integrated MCDM approach is proposed for evaluation of public transportation systems based on Delphi method, group analytic hierarchy process (GAHP) and preference ranking organization method for enrichment of evaluations (PROMETHEE). The proposed model provides more reliable and realistic results and introduces directions for future improvements of public transportation service quality. A sensitivity analysis is applied to investigate the influence of criteria weights on the decision making problem. As a conclusion, the most important public transportation systems in Tehran orderly are: metro, taxi, BRT, bus and van. Therefore, Tehran Municipality and policy makers should encourage and support the previously mentioned systems
Perceptions of safety climate in construction projects between workers and managers/supervisors in the developing country of Iran
202208 bckwSelf-funde
Overhead distribution lightning performance on joint use concrete poles with transmission lines
Electrical power is an essential source of comfort, numerous tasks are almost impossible to be performed without the aid of the electrical power. To keep up with the population growth worldwide, electrical infrastructure are being upgraded and up-rated. To maximize the use to the land and reduce construction cost, joint-use structures between distribution and transmission line are broadly deployed. These joint structures introduce the overhead earth wire (OHEW), pole earth grids and taller poles to the distribution network. This paper endeavours to study the impact that these joint structures have on the lightning performance of the distribution line. Furthermore, the works provide important information on lightning performance and determine when these joint structures worsen or enhancing the lighting performance of the distribution asset. Case study is also included
Analysis and performance of a switched reluctance generator for wind energy conversion
The concept of operation for the switched reluctance generator is divided into two sections, first is the excitation stage and second is the generating stage. This paper discuss the determination of the coil excitation in the SRG, the switching phenomena, requirement to protect the machine from electrical damage as well as the electric losses limitations
Determining and assessing the significant barriers of transferring unfinished construction projects from the public sector to the private sector in Iran
202303 bcwwAccepted ManuscriptSelf-fundedPublishe
Critical success factors for private sector participation in accomplishing abandoned public sports facilities projects in Iran
202307 bckwNot applicableSelf-fundedEarly release12 month
Study on excitation control of switched reluctance generator for wind energy conversion
This paper will discuss the advantages of using Switched Reluctance Generator (SRG) for wind energy applications. Specifically, the theoretical and experimental study of the self excitation of a SRG and the determination of the variable parameters in a SRG design are discussed. The switching requirements for the converter and the design parameters for the maximum power output of the SRG are computed using Matlab simulation. The design of the circuit which controls the variable parameters in a SRG, in order to provide the maximum power output is also discussed
A multi-criteria optimization study for locating industrial warehouses with the integration of BIM and GIS data
202207 bckwAccepted ManuscriptSelf-fundedPublishe
Switched reluctance generator for wind power applications
Green house effect has becomes a serious concern in many countries due to the increase consumption of the fossil fuel. There have been many studies to find an alternative power source. Wind energy found to be one of the most useful solutions to help in overcoming the air pollution and global. There is no agreed solution to conversion of wind energy to electrical energy. In this paper, the advantages of using a Switched Reluctance Generator (SRG) for wind energy applications. The theoretical study of the self excitation of a SRG and the determination of the variable parameters in a SRG design are discussed. The design parameters for the maximum power output of the SRG are computed using Matlab simulation. The designs of the circuit to control the variable parameters in a SRG to provide the maximum power output are also discussed
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