safety,risk and reliability
mahmoud Shahrokhi; Mohammad Farhadi
Abstract
In combined cycle power plants, instead of releasing gases which are produced from burning fossil fuels, after turning the gas turbines, they enter into heat recovery steam generator (HRSG) boilers to produce steam. The produced steam by these boilers is used to generate electricity in steam turbines ...
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In combined cycle power plants, instead of releasing gases which are produced from burning fossil fuels, after turning the gas turbines, they enter into heat recovery steam generator (HRSG) boilers to produce steam. The produced steam by these boilers is used to generate electricity in steam turbines and thus, electricity generation efficiency is dramatically increased. In this way, the efficiency of electricity production increases significantly. These boilers are made at a great cost and also, any failures of them cause a power plant to stop and create enormous costs, so optimizing their reliability is very important. This paper deals with the modeling of the HRSG feed water system by using a block diagram for two states (i.e. half-time and full load), to evaluate the difference between the proposed alternative designs, by considering their reliability. The method used in this paper can be applied to evaluate and optimize the reliability of many other industrial systems.
perfomance management
Sharmineh Safarpour; Alireza Amirteimoori; Sohrab Kordrostami; Leila Khoshandam
Abstract
Due to the importance of the health sector in the people’s lives, attention and monitoring of this sector can lead to development and social welfare. In this paper, data on 31 educational and therapeutic hospitals are considered to analyze their performance and managerial ability. A two-step procedure ...
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Due to the importance of the health sector in the people’s lives, attention and monitoring of this sector can lead to development and social welfare. In this paper, data on 31 educational and therapeutic hospitals are considered to analyze their performance and managerial ability. A two-step procedure is used to evaluate the relative efficiency and to measure the impact of contextual variables. Toward this end, in the first step, data envelopment analysis has been used to calculate the technical efficiencies of the hospitals, and then the logarithm of the technical efficiency obtained from the first step was regressed on a set of contextual variables that affect the performance of hospitals. Then, the residual is interpreted as managerial ability of the hospitals. At the end, a unique ranking was presented based on the criteria of managerial ability of each unit. Finally, the results were analyzed and analyzed in order to provide valuable suggestions for managers and more efficient management of the country's hospitals and to maintain the health of the society. According to the study carried out without considering contextual variables, 25 efficient units were evaluated, but by applying the effect of contextual variables on the efficiency, no unit becomes efficient, this proves the high impact of such indicators on the performance of units he does. Also, in the ranking of the units with the approach of managerial ability, Lorestan province is in the first place and Golestan province is in the last place.
Taher kouchaki tajani; Ali Mohtashami; maghsoud Amiri; Reza Ehtesham Rasi
Abstract
in this paper we have proposed a model based on Mixed Integer Non-Linear Programming for the blood supply chain under conditions of uncertainty in supply and demand, from the stage of receiving blood from volunteers to the moment of distribution in demand centers. The challenges addressed in this optimization ...
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in this paper we have proposed a model based on Mixed Integer Non-Linear Programming for the blood supply chain under conditions of uncertainty in supply and demand, from the stage of receiving blood from volunteers to the moment of distribution in demand centers. The challenges addressed in this optimization model are the reduction of blood supply chain costs along with minimizing the shortage and expiration rate of blood products. The Markov chain has been used to address the uncertainty of donor blood supply. And to estimate the needs of medical centers, the received demand is considered fuzzy. Then The proposed model is solved in small dimensions by GAMS software and in large dimensions by Bat and Whale meta-heuristic algorithms and the results are presented. In addition, a case study is presented to show the applicability of the proposed model. The results show a reduction in the level of costs as well as a reduction in the shortage and expiration of blood products in the supply chain.
supply chain management
Akbar Rahimi; mohamad hossein karimi govareshki; Amirreza zareei
Abstract
The competitive landscape among companies and their supply chains necessitates a heightened focus on collaborating with best suppliers and business partners. The appropriate selection of suppliers presents an opportunity for organizations to gain a sustainable competitive advantage while enhancing profitability. ...
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The competitive landscape among companies and their supply chains necessitates a heightened focus on collaborating with best suppliers and business partners. The appropriate selection of suppliers presents an opportunity for organizations to gain a sustainable competitive advantage while enhancing profitability. The Etka organization, responsible for meeting the consumption and general needs of the armed forces, is no exception. Consequently, it requires establishing partnerships with the best suppliers across industries. To address this need, this research aims to provide a framework for selecting suppliers with lean, agile, and resilient approaches within the supply chain of the Etka organization. To achieve this objective, an extensive review of the relevant literature on lean, agile, and resilient supplier selection was undertaken. Through this process, key selection criteria were identified, and the fuzzy screening method was employed to localize and refine these criteria. Furthermore, the combined rough best-worst method was utilized to assign weights to each criterion, reducing uncertainties associated with expert opinions. "Cooperation and coordination" emerged as the most critical criterion from the resilient supply perspective, "trust development" from the agile supply approach, and "product quality" from the lean supply approach. The application of the Rough VIKOR method then facilitated the ranking of selected suppliers, resulting in the Qa'emshahr canning company being identified as the most desirable supplier in the related industry. This study presents a comprehensive framework for selecting lean, agile, and resilient suppliers within the supply chain of the Etka organization, enabling fruitful partnerships that contribute to competitive advantage and overall profitability.
Industrial management
Mohsen Kochaki; Behnam Vahdani
Abstract
The correct storage and arrangement of products in the warehouse increases the efficiency in responding to requests, accelerates the identification of products, increases the accessibility of the items in the warehouse, makes more use of the available space in the warehouse, determines the position of ...
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The correct storage and arrangement of products in the warehouse increases the efficiency in responding to requests, accelerates the identification of products, increases the accessibility of the items in the warehouse, makes more use of the available space in the warehouse, determines the position of the products in the warehouse and does not damage it. maximum flexibility and optimal storage conditions are provided. By examining the studies that have been conducted in the field of warehousing and arrangement of products in the warehouse, and before arranging the products in the warehouse, comprehensively and comprehensively, according to the characteristics of the goods, they have not been categorized. Therefore, in this article, by using machine learning algorithms and data mining, according to the characteristics that are considered for the goods in the warehouse of Farasan industrial-production factory, the products are categorized and then the products are arranged in the warehouse using We have paid mathematical programming model. The purpose of the investigated problem in the field of warehousing and arrangement of products, in addition to categorizing products based on their characteristics, is to minimize the cost function obtained in relation to the mathematical planning model. Therefore, for the category Classification of goods is done using density-based algorithm (DB), self-organizing mapping neural network (SOM) and hierarchical clustering method (AGNES). The obtained results show that the SOM network has a better performance than the density-based algorithm and also the density-based algorithm has a better performance than the hierarchical clustering method.
supply chain management
Ali Mirzaei; Esmaeil Mazroui Nasrabadi
Abstract
The supply chain of the food industry is very important for countries. In recent years, occurrences such as floods, frost, heatstroke, shutdown of some layers of the supply chain, cause a ripple effect in the supply chain of food products. The occurrence of disturbances and specifically the ripple effect ...
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The supply chain of the food industry is very important for countries. In recent years, occurrences such as floods, frost, heatstroke, shutdown of some layers of the supply chain, cause a ripple effect in the supply chain of food products. The occurrence of disturbances and specifically the ripple effect can make the country face many challenges, therefore it is necessary to identify and analyze the strategies to deal with the ripple effect. This research has been done in two stages: qualitative (with the aim of identifying coping strategies) and quantitative (with the aim of scenario modeling and analysis). The method of analysis is thematic analysis in the first stage and fuzzy cognitive map in the second stage. The findings show 84 primary codes that were grouped into 21 sub-categories and 4 main categories of "Strategic Management", "Operations Management", "Compilation and Correct Implementation of Laws" and "Supply Chain Management". The analysis of backward scenarios shows the importance of "supplier relationship management", "cooperation and coordination in the supply chain" and "contingency plans", and the analysis of forward scenarios shows the importance of "monitoring environmental changes" and "strategic plan”. Focusing on short-term plans, improving the capabilities of managers in the field of decision-making and problem-solving skills, adjusting supplier selection criteria, improving the design of the supply network based on backup locations, and the existence of safety stock for strategic goods should be the attention of industrialists.
safety,risk and reliability
Amir Hossein Soltaninia; Mahdi Ravanshadnia; Milad Ghanbari
Abstract
Occupational Health and Safety (OHS) management significantly affects reducing costs, increasing productivity, and social credibility of construction companies and plays a facilitating role in the transition towards sustainable development. This study aims to identify and quantitatively analyze OHS risks ...
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Occupational Health and Safety (OHS) management significantly affects reducing costs, increasing productivity, and social credibility of construction companies and plays a facilitating role in the transition towards sustainable development. This study aims to identify and quantitatively analyze OHS risks in sustainable construction projects in Iran. To do this, first, common OHS risks are identified by conducting library studies. Then, these risks are screened and localized for Irans' sustainable construction projects by surveying 13 experts, selected by snowball sampling method, in a focus group meeting. Afterward, each risk's importance and priority are determined using the Neutrosophic Group Best-Worst Multi-criteria (NGBWM) method, while applying a weight to each expert's opinion. The Neutrosophic sets theory provides the basis for obtaining accurate and more reliable results by considering the uncertainties in the experts' opinions. The findings showed that "the lack of sufficient safety skills of employees due to not allocating time to specialized safety training", "occupational injuries and diseases", "hazards caused by improper design and layout of the project site", "Weakness and inefficiency of occupational health and safety management personnel", and "Negligence and lack of planning for emergency maneuvers", with weights of 0.052, 0.036, 0.035, 0.032 and 0.028 are respectively as the most critical OHS risks in Iran's sustainable construction projects. Finally, reactive and preventive responses were proposed to face them in detail.
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