Reliability and Quality Engineering
Rasoul Jamshidi; Mohammad Ebrahim Sadeghi
Abstract
As manufacturers and technologies become more complicated, manufacturing errors such as machine failure and human error have also been considered more over the past. Since machines and humans are not error-proof, managing the machines and human errors is a significant challenge in manufacturing systems. ...
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As manufacturers and technologies become more complicated, manufacturing errors such as machine failure and human error have also been considered more over the past. Since machines and humans are not error-proof, managing the machines and human errors is a significant challenge in manufacturing systems. There are numerous methods for investigating human errors, fatigue, and reliability that categorized under Human Reliability Analysis (HRA) methods. HRA methods use some qualitative factors named Performance Shaping Factors (PSFs) to estimate Human Error Probability (HEP). Since the PSFs can be considered as the acceleration factors in Accelerated Life Test (ALT). We developed a method for Accelerated Human Fatigue Test (AHFT) to calculate human fatigue, according to fatigue rate and other effective factors. The proposed method reduces the time and cost of human fatigue calculation. AHFT first extracts the important factors affecting human fatigue using Principal Component Analysis (PCA) and then uses the accelerated test to calculate the effect of PSFs on human fatigue. The proposed method has been applied to a real case, and the provided results show that human fatigue can be calculated more effectively using the proposed method.
Engineering Optimization
Sh. T. Alam
Abstract
The development of a product demands numbers of consideration and customer-based product dominates the present market. This study aims to formulate a customer-oriented product and investigate the optimum design parameters level for this formulation. The customer-oriented product named 'CNC PCB Plotter' ...
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The development of a product demands numbers of consideration and customer-based product dominates the present market. This study aims to formulate a customer-oriented product and investigate the optimum design parameters level for this formulation. The customer-oriented product named 'CNC PCB Plotter' – is proposed as a handy tool to make a single PCB within a short time and cost. In the sophisticated art of product design, the desires of the customer should be the only constraint. With this in mind, an organized approach is conducted to formulate the product. Suitable design parameters with their optimum ranges provide the sustainability of the product. Response Surface Methodology (RSM) is applied to determine the optimum level of design parameters. A 2-level 3 factorial Central Composite Design (CCD) provides the experimental trails. This research involves the customer demand and specifies the design parameter, such as cutting speed, feed rate, and depth of cut. The average dimensional accuracy is taken as a response and found 0.027 µm with a combination of cutting speed 53.676 m/min, feed rate 253.272 mm/min, and depth of cut 0.49.mm, which is found to be the optimum value.
Nazila Adabavazeh; Atefeh Amindoust; Mehrdad Nikbakht
Abstract
In any country's economy, the distribution is one of the most important industries and infrastructure. The industry's 8% portion of national income, explains the wide range of this industry and consequently the key role of this industry in the supply chain of many industries in the country. Not using ...
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In any country's economy, the distribution is one of the most important industries and infrastructure. The industry's 8% portion of national income, explains the wide range of this industry and consequently the key role of this industry in the supply chain of many industries in the country. Not using all the capabilities of the distribution network and ignorance about distribution enablers will lead to chain costs failure and increase supply. In today's condition, maintenance and continuity of activities in the distribution network are considered as important subjects in a supply chain, and the reliability of the distribution network in a supply chain is grounded in recognition of the enablers. Identifying and prioritizing the distribution network enablers precede the development and proper implementation of the strategies and plans of a distribution network. The fuzzy logic has become a convenient tool for prioritizing due to the necessity of the comprehensive view to the supply chain, the uncertain space of it, and inconsistency in the views of decision-makers. This research tries to identify and prioritize the empowerment in order to direct and supply resources and thus to increase the productivity and effectiveness of the country's industrial distribution network.The theoretical framework of the study is based on the extracted enablers from the literature and selecting a final set of them by using the Lawshe method. The group of experts is comprised of 11 experts in the welding and cutting industry. The enablers are prioritized using the fuzzy BWM method and Lingo software. The results indicate that the most influencing factor on the distribution network is "on-time delivery" and the "logistic infrastructures" factor is the least important among the factors. The resulted prioritization could be used as a guideline for a better perception of the activities related to the distribution network.
Innovation, knowledge management, and organizational learning
Vusumuzi Malele; Mhlambululi Mafu
Abstract
All engineering graduates must possess specific essential competencies when leaving universities to transition to the industry or be successful in the world of work. This paper adopts a literature review approach to synthesise available secondary data regarding creating harmony among engineering disciplines. ...
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All engineering graduates must possess specific essential competencies when leaving universities to transition to the industry or be successful in the world of work. This paper adopts a literature review approach to synthesise available secondary data regarding creating harmony among engineering disciplines. It uses the illustration of a vending machine to indicate how various engineering disciplines could be harmonised through the Learning Factory platform. Moreover, it provides some ideas for harmonising engineering disciplines. The main findings of this work suggest that the Learning Factory concept is a critical ideology that is worth implementing, especially by developing. The Learning Factory environment can produce well-rounded graduates capable of applying technical and non-technical skills to solve community challenges, including being entrepreneurial and innovative to drive economic growth and development. The paper concludes by providing insights demonstrating that the concept of a Learning Factory can also be utilized for addressing other engineering and industrial-related challenges.
Inventory, logistics, and transportation
Ch. G. Udoka
Abstract
The aim of this study is to examine the impact of passengers’ traffic on Exchange Rate (ER) and economic growth in Nigerian aviation industry. This study adopts an ex-post facto research design, a systematic empirical inquiry in order to carry out the research. Secondary data was obtained from ...
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The aim of this study is to examine the impact of passengers’ traffic on Exchange Rate (ER) and economic growth in Nigerian aviation industry. This study adopts an ex-post facto research design, a systematic empirical inquiry in order to carry out the research. Secondary data was obtained from the Federal Airports Authority of Nigeria (FAAN) and National Bureau of Statistics (NBS). The study employed trend analysis on the time series data and regression analysis to explore the cause-and-effect relationship among variables. The result showed that the trend of exchange rate and aviation contribution to Gross Domestic Product (GDP) have been on increase over certain periods. Hence, the linear trend line shows a steady increase in the pattern of exchange rate and economic growth over the sample period of 2000 to 2020 with R-squared values of 0.714 and 0.824, respectively indicating a good fit of the line to the data. The regression analysis revealed that Passengers’ Traffic (PT) has a positive impact on ER and economic growth. Thus, with a T-statistic of 3.296 and probability of 0.004, it indicates a statistically significant effect on the dependent variable (i.e. Exchange Rate). Also, with a T-statistic of 6.119 and probability of 0.000, it indicates a statistically significant impact on the dependent variable (i.e. Economic Growth).
Business Analytics
Leila Negahban; Bahman Banimahd; Seyed Hossein Hosseini; Azam Shokri Cheshmeh Sabzi
Abstract
The purpose of this research is to evaluate and rank the efficiency of pharmaceutical companies in creating operational cash flows in line with the objectives of financial reporting. The research method for collecting theoretical bases and research data is library studies. In this research, in order ...
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The purpose of this research is to evaluate and rank the efficiency of pharmaceutical companies in creating operational cash flows in line with the objectives of financial reporting. The research method for collecting theoretical bases and research data is library studies. In this research, in order to evaluate the efficiency of pharmaceutical companies in creating operational cash flow, the Data Envelopment Analysis (DEA) model with weight limit is used. The results of this research show that Farabi pharmaceutical company has the highest efficiency score in creating Operating Cash Flows (OCFs) and Loqman pharmaceutical company has the lowest efficiency score. The findings of this research confirm that DEA is a suitable technique for evaluating the performance of companies in creating operational cash flow. Also, this technique, along with traditional financial analysis, can be considered a useful instrument for deciding and evaluating the performance and efficiency of companies. This article can make analysts more familiar; financial and accounting researchers with DEA applications in financial and accounting analysis. Also, this research can expand the use of scientific models in financial and accounting research.
Design of Mechanical and Thermal Systems
Ekpenyong Akanimo Udofia; Aniekan Essienubong Ikpe; Victor Etok Udoh
Abstract
In this paper, the performance characteristics of a fabricated horizontal axis wind turbine with and without flanged diffusers were studied using wind tunnel experiment. Measurements of global parameters (power, torque, rotational speed efficiency, etc.) were carried out at wind speed regime between ...
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In this paper, the performance characteristics of a fabricated horizontal axis wind turbine with and without flanged diffusers were studied using wind tunnel experiment. Measurements of global parameters (power, torque, rotational speed efficiency, etc.) were carried out at wind speed regime between 3-7 m/s. Flanged diffusers of five different inlet-outlet diameter ratios were employed. The results showed minimum mean increments in tip-speed ratios (TSR) of about 45 % with the smallest diffuser and a maximum of 80 % with the largest diffuser. Increments in the torque even at modest wind speed of 4 m/s were as much as 65, 70 and 76 % for the largest three diffusers and about 33 % for the smaller diffuser. The power output (with and without diffuser) gradually increased from 3-7 m/s wind speed, while the power coefficient (Cp) increased from 3-5.5 m/s, and thereafter began to fluctuate as the wind speed approached 7 m/s. Comparatively, maximum Cp of the turbine without diffuser was 0.22 for λ=0.534 at a wind speed of 7 m/s, while the maximum average value of Cp for turbine with flanged diffuser 3 was 0.34 for λ=0.706 at the same wind speed. As a result of the flanged diffuser attachment, the maximum Cp increased by 36 %. The results showed mean incremental values of 52 and 57 % with the greater value obtained from the second largest diffuser (Di/Do = 0.70) and the least value from the largest diffuser (Di/Do = 0.80), while the first three diffusers achieved near identical increments of 55 %. This consequently implies that increments in the extracted power (i.e., Cp) above 5 m/s wind speed declined with indications of separation and turbulence in the flows beyond the rotor.
Supply chain management
Vajiheh Torkian; Amir Abbas Shojaie; Omid Boyer Hassani
Abstract
Supply chain management is a process in which a number of organizations work together as a supply chain until the raw materials reach the manufacturer and finally, a valuable product is provided to the end consumer. With the increase in population and the increase in environmental sensitivities, the ...
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Supply chain management is a process in which a number of organizations work together as a supply chain until the raw materials reach the manufacturer and finally, a valuable product is provided to the end consumer. With the increase in population and the increase in environmental sensitivities, the forward-reverse supply chain has attracted a lot of attention, which pursues goals such as optimization, customer satisfaction, responding to their needs in the shortest time with the lowest cost and high quality. In this paper, a forward- reverse multi-product and multi-period network is designed under the condition of uncertainty in the demand parameter. The purpose of the proposed model is to maximize profit by considering customer satisfaction simultaneously and reducing delay and the fuzzy approach has been used to solve the model under conditions of uncertainty. The proposed model is mixed-integer linear programming and for its validation and applicability, it has been solved by GAMS software, a numerical example using simulated data in deterministic and uncertain state. The results of the analysis of the numerical example show that the show that with increasing uncertainty in the demand parameter, the optimal value of the objective function decreases.
Operations Research
Seife Ebeyedengel Tekletsadik
Abstract
Productivity improvement is important for the sustainability of the business. However, before improvement it is important to measure the existing system productivity level. In this sense, the productivity of the case company has been measured by using the PO-P approach. Using this approach, the overall ...
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Productivity improvement is important for the sustainability of the business. However, before improvement it is important to measure the existing system productivity level. In this sense, the productivity of the case company has been measured by using the PO-P approach. Using this approach, the overall productivity of the case company has become 0.652. By having the ergonomic sub system and strategic goal of the case company, goal programing has been formulated to show by how much percent does the ergonomics subsystem alone will improve the overall productivity level. For this, it is required to have optimal solution of performance value of the performance objectives of the ergonomics sub-system. The optimal solution of the excel solver has given the suggested performance values of x3=1.035, x4= 0.82, x5=0.7, x6=0.8, x7=2.76, x8=0.75, x9=0.8, x10=0.5, and x11=0.4. Having these values, the productivity of the ergonomics subsystem became 1.492, in effect increased the overall productivity from 0.652 to 0.776.
Economics
Mobasshira Zaman
Abstract
The COVID-19 pandemic has caused unprecedented disruption to the global economic structure, resulting in significant changes in spending patterns for households worldwide. Developed countries like the United States have been affected as well, struggling to return to pre-pandemic stable economic situations. ...
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The COVID-19 pandemic has caused unprecedented disruption to the global economic structure, resulting in significant changes in spending patterns for households worldwide. Developed countries like the United States have been affected as well, struggling to return to pre-pandemic stable economic situations. This study focuses on the impact of the pandemic on household expenditure in the United States, using ANOVA to compare household expenses between the pre-COVID period in 2018 and the post-COVID period in 2021. The results of the study showed a significant increase in all types of household expenditure from pre-COVID to post-COVID periods, highlighting the correlation between the pandemic and changes in spending habits. This trend is further fueled by price increases in daily necessities, inflation of the dollar, and scarcity of goods. The analysis also revealed that the trend was increasing, emphasizing the need for immediate policy interventions to address the issue. Further research is needed to identify the specific types of expenditure driving this increase and the underlying reasons behind it. The implications of the study are significant for policymakers and economists as they underscore the need for effective interventions to stabilize household expenditure and promote economic recovery in the wake of the pandemic. The findings also highlight the importance of utilizing statistical methods such as ANOVA to evaluate complex economic systems and guide evidence-based policy interventions. As future research continues to explore the impact of the pandemic on economic structures worldwide, this study provides valuable insights into the specific changes in household expenditure in the United States, emphasizing the urgent need for targeted policy interventions to address these changes.
Silas Oseme Okuma; Martins Ufuoma Eki; John Damilola Oluwafemi; Chukwuekum Orumgbe
Abstract
The most desired strength value in any welding process is an excellent Ultimate Tensile Strength (UTS) of the weld in respect to the parent metal. Welding process parameters should be monitored and reviewed on a continuous basis due to the increased demand for structural and industrial materials with ...
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The most desired strength value in any welding process is an excellent Ultimate Tensile Strength (UTS) of the weld in respect to the parent metal. Welding process parameters should be monitored and reviewed on a continuous basis due to the increased demand for structural and industrial materials with higher strength weld joints. The goal of this study is to look into the limitations of the investigated industrial firm's existing GMAW welding process parameters used in the welding procedure, and to propose alternative, uniquely designed, and improved process parameters to replace its existing procedure welding protocol, thereby improving weld results by achieving higher Ultimate tensile strength. The proposed process parameters were then compared to available literature, and optimization was performed using the Response Surface Method.Tensile strength was determined on GMAW welding plates of 200mm by 20mm. The RSM Analysis was used to examine the data acquired from the experimental findings, and the results show that the current, voltage, and travel speed had the most significant effect on the ultimate weld strength. Furthermore, the findings show a high link between the actual and predicted ultimate tensile strength. Maximum ultimate tensile strengths of 425, 450, and 475Mpa were attained at welding voltages of 28 v, currents of 240 A, and travel speeds of 0.012 m/s .
Inventory, logistics, and transportation
Amin Farahbakhsh; Amir Saman Kheirkhah
Abstract
The inventory routing problem arises from the combination of the vehicle routing problem and the vendor-managed inventory problem. In this paper, we present a mathematical model and a novel genetic algorithm for solving the multi-period inventory routing problem. The objective is to supply products to ...
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The inventory routing problem arises from the combination of the vehicle routing problem and the vendor-managed inventory problem. In this paper, we present a mathematical model and a novel genetic algorithm for solving the multi-period inventory routing problem. The objective is to supply products to scattered customers within a given time horizon while managing customer inventories to avoid shortages and minimize total inventory and transportation costs. To represent solutions for this problem, we introduce a new chromosomal structure. This structure offers simplicity in encoding and decoding solutions, maintains feasibility after crossover and mutation operations, addresses both routing and inventory management in a single step, and consolidates information about each solution method comprehensively. The algorithm parameters, including crossover and mutation rates, population size, number of iterations, and selection pressure, are fine-tuned using the Taguchi method. To assess algorithm efficiency, we utilize standard instances from the literature. Our results demonstrate that the proposed algorithm performs favorably compared to previous approaches.
Metaheuristics Algorithms
Fatemeh Sogandi
Abstract
Curve fitting is a computational problem in which we look for a base objective function with a set of data points. Recently, nonparametric regression has received a lot of attention from researchers. Usually, spline functions are used due to the difficulty of the curve fitting. In this regard, the choice ...
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Curve fitting is a computational problem in which we look for a base objective function with a set of data points. Recently, nonparametric regression has received a lot of attention from researchers. Usually, spline functions are used due to the difficulty of the curve fitting. In this regard, the choice of the number and location of knots for regression is a major issue. Therefore, in this study, a Genetic algorithm simultaneously determines the number and location of the knots based on two criteria comprise of least square error and capability process index. The proposed algorithm performance has been evaluated by some numerical examples. Simulation results and comparisons reveal that the proposed approach in curve fitting has satisfactory performance. Also, a sensitivity analysis on the number of knots has been illustrated by an example. Finally, simulation results from a real case in statistical process control show that the proposed Genetic algorithm works well in practice.
Data Envelopment Analysis, DEA
Abbas Ghomashi Langroudi; Masomeh Abbasi
Abstract
The Cross-efficiency method in data envelopment analysis (DEA) has widely been used as a suitable utility for ranking decision-making units (DMUs). In this paper, for overcoming the issue of the existence of multiple optimal solutions in cross-efficiency evaluation, we use the neutral strategy to design ...
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The Cross-efficiency method in data envelopment analysis (DEA) has widely been used as a suitable utility for ranking decision-making units (DMUs). In this paper, for overcoming the issue of the existence of multiple optimal solutions in cross-efficiency evaluation, we use the neutral strategy to design a new secondary goal. Unlike the aggressive and benevolent formulations in cross-efficiency evaluation, the neutral cross-efficiency evaluation methods have been developed in a way that is only concerned with their own interests and is indifferent to other DMUs. The proposed secondary goal introduces a new cross-efficiency score by maximizing the sum of the output weights. The first model is then extended to a cross-weight evaluation, which seeks a common set of weights for all the DMUs. Finally, we give two numerical examples to illustrate the effectiveness of the proposed neutral models and the potential applications in ranking DMUs by comparing their solutions with those of alternative approaches.
Inventory, logistics, and transportation
Kehinde Adegbola; Abdulrakib Abdulrahman
Abstract
Consignment stocks agreement had been very useful in inventory control. The benefit ranges from improved cash flow, reduced risk level, savings on investment, reduced ownership cost, low inventory carrying cost and regular restocking to mention few. Also, small batch delivery is an effective strategy ...
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Consignment stocks agreement had been very useful in inventory control. The benefit ranges from improved cash flow, reduced risk level, savings on investment, reduced ownership cost, low inventory carrying cost and regular restocking to mention few. Also, small batch delivery is an effective strategy for launching a product since it enables a business to assess the market and validate the product before committing to a large production run. In this paper, we combined small batch delivery and consignment stock policy by considering a supply chain setting where a vendor fulfilled the shipment requirement of each buyer sequentially in a single production set up. To achieve this, and as against the equal size shipments policy assumed in literature for different buyers, the vendor sends a smaller shipment first as early entry, followed by n equal shipments. These n shipments are proportionately increased according to the vendor rate of production to each buyer’s demand rate. A mathematical cost function is developed to reduce the overall cost of the integrated supply chain system through the optimal cycle time and the optimal numbers of shipments to be delivered to each buyer. Numerical example is given using data from an existing literature, results were compared, and the new distribution policy gives better financial savings in terms of cost over the equal shipment policy assumed in literature. Sensitivity analyses were performed on key parameters to evaluate the robustness of the model.
Scheduling
Esmaeil Mehdizadeh; Fatemeh Soleimaninia
Abstract
The Flexible Job shop Scheduling Problem (FJSP), as a Production Scheduling Problem (PSP), is generally an extension of the Job shop Scheduling Problem (JSP). In this paper, the FJSP with reverse flow consisting of two flows of jobs (direct and reverse) at each stage is studied; the first flow initiates ...
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The Flexible Job shop Scheduling Problem (FJSP), as a Production Scheduling Problem (PSP), is generally an extension of the Job shop Scheduling Problem (JSP). In this paper, the FJSP with reverse flow consisting of two flows of jobs (direct and reverse) at each stage is studied; the first flow initiates in Stage 1 and goes to Stage C (the last stage), and the second flow starts with Stage c and ends up in Stage 1. The aim is to minimize the makespan of the jobs (the maximum completion time). A Mixed Integer Programming (MIP) is presented to model the problem and the Branch and Bound (B&B) method is used to solve the problem. A numerical small-size problem is presented to demonstrate the applicability, for which the Lingo16 software is employed for a solution. Due to the NP-hardness of the problem, a meta-heuristic, namely the Vibration Damping Optimization (VDO) algorithm with tuned parameters using the Taguchi method, is utilized to solve large-scale problems. To validate the results obtained using the proposed solution algorithm in terms of the solution quality and the required computational time, they are compared with those obtained by the Lingo 16 software for small-size problems. Finally, the performance of the proposed algorithm is compared with a Genetic Algorithm (GA) by solving some randomly generated larger-size test problems, based on which the results are analyzed statistically. Computational results confirm the efficiency and effectiveness of the proposed algorithm and show that the VDO algorithm performs well.
Scheduling
Saeideh Naderi; Mohsen Vaez-Ghasemi; farzad movahedi sobhani
Abstract
The Resource-Constrained Project Scheduling Problem (RCPSP) is a general one in scheduling which possesses various applications in production, production scheduling, project managing and other criteria. This issue has been studied since 1960 and is very complicated. In this study, the common presuppositions ...
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The Resource-Constrained Project Scheduling Problem (RCPSP) is a general one in scheduling which possesses various applications in production, production scheduling, project managing and other criteria. This issue has been studied since 1960 and is very complicated. In this study, the common presuppositions and limitations regarding such problems will be investigated in addition to their reliability in modelization in order to investigate the possibility of availability of renewable resources using a new attitude. The objective of modelization of RCPSP is quantification of total costs and minimization of delays in projects. Therefore, in order to mathematically modelize RCPSP, non-linear complex integer math programming which transforms into a linear programming model using the features of exponential functions is used. In order to solve the final linear math problem, some experimental examples will be designed in different dimensions, so that the performance and efficiency of the designed model are studied. For solving problems with low dimensions , the Epsilon Constraint multi-objective optimization method is used in an exact optimization software like Lingo. In order to find out the solutions of the ones whose dimensions are high, which exact methods can not solve,the meta-heuristic algorithm called NSGA-II which is a strong one to optimize multi objective problems is used. The results of using these algorithms and the statistical analysis which shows their reliability as 95 percent , indicates that the performance is suitable for genetic algorithms. Therefore this meta-heuristic algorithm has more efficiency and more apposite performance for the recommended model compared with the software of exact optimization. Using the designed math model ,this study can result in decreasing the times of delay in projects and the costs in the scheduling problem and also increasing the reliability when activities are multi-mode.
Supply chain management
davod Andalib Ardakani; Mehrdad Kiani; Ali saffari darberazi; Fatemeh Zamzam; Elham Mofatehzadeh
Abstract
The purpose of this study was to design a model for identifying and ranking the factors influencing green supply chain management in the tile and ceramic industry, which is a significant industry in Iran. The study consisted of three main stages.In the first stage, a systematic review of the literature ...
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The purpose of this study was to design a model for identifying and ranking the factors influencing green supply chain management in the tile and ceramic industry, which is a significant industry in Iran. The study consisted of three main stages.In the first stage, a systematic review of the literature and the Meta-synthesis method were employed to identify and categorize the factors that contribute to the success of green supply chain management. In the second stage, The factors were thoroughly examined and refined through the content validity method. As a result of these steps, a comprehensive model was developed, comprising 30 factors categorized into six dimensions: green suppliers, green technology and expertise, green human resources, green products, Green Organization and Communications, and Green regulations and Support. In the third stage, the Interval Type-2 Fuzzy Analytic Hierarchy Process (IT2FS-AHP) method was utilized to rank the dimensions and factors. Experts' opinions were gathered through a questionnaire to determine the importance of each dimension and factor. The results indicated that the dimensions of green technology and expertise, as well as Green regulations and Support, were deemed the most critical. Furthermore, factors such as "Attention to social responsibility in the organization," "Design and development of evaluation and selection systems of suppliers based on environmental criteria," and "support of operational, middle, and senior managers in implementing the green supply chain" were identified as highly influential in the success of green supply chain management. Overall, the identification and ranking of key factors in green supply chain management contribute to mitigating the adverse environmental impact of industrial activities and enhancing customer satisfaction.
Clustering
Mehdi Ajalli
Abstract
Classification is one of the important tasks in any work and field. Cluster analysis (CA) is one of the most important classification methods. CA is one of the widely used methods in many scientific fields. Clustering is one of the most popular data mining techniques with many applications in industry. ...
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Classification is one of the important tasks in any work and field. Cluster analysis (CA) is one of the most important classification methods. CA is one of the widely used methods in many scientific fields. Clustering is one of the most popular data mining techniques with many applications in industry. Especially, in the field of human resources management, the use of predefined rules is used to determine the performance and division of employees. The main goal of the current research is to design a suitable model for allocating rewards to employees by using the combined approach of the Group Analytical Hierarchy Process (GAHP) and CA. The research method is practical in terms of purpose and descriptive-survey in terms of data collection. For this purpose, first, by designing and distributing a comparative questionnaire of indicators and completing them by the experts of Shahid Fakuri Industries' component manufacturing unit, and by using the group hierarchical analysis process model with Expert Choice software, the weight of the effective indicators in employee evaluation was calculated, then the values of the indicators for 29 employees with using the formula of the normalization function in the Excel software, it is standardized and the weight of the indicators is multiplied by the standard values of the data, and then the distance matrix and the optimal number of clusters are calculated through the Machaon software, and finally, using the discriminative clustering approach and using the K-means method, data clustering was done with SPSS and Makaon software and a suitable model was presented for allocating rewards to the workers of the parts making unit.
Case studies in industry and services
Saeed Rasouli Pareh Yousefian; Jaffar Barghi Mogaddam; Hamid Janani; Mohammad Rahim Najafzadeh; Afshin Roshan Milani
Abstract
In this paper, the prioritization and weighting of different methods of using renewable energy, as well as the feasibility of using renewable energy in the management of sports venues in the water and electricity industry of east Azerbaijan province, have been discussed. The D-number theory method has ...
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In this paper, the prioritization and weighting of different methods of using renewable energy, as well as the feasibility of using renewable energy in the management of sports venues in the water and electricity industry of east Azerbaijan province, have been discussed. The D-number theory method has been used to prioritize different methods of using renewable energy. The results of gathering information from experts in this field, show that using solar energy with a weight of 0.5345 is the best method for producing electrical energy in sports and welfare venues. Also, the use of wind energy with a weight of 0.5183 and the use of water energy with a weight of 0.5126 are in the next ranks, respectively. The indicators used in ranking factors include total costs, energy efficiency and compatibility with environmental conditions. Based on the results of the feasibility study and the available findings, it can be seen that the total cost of using renewable energy in the sports and welfare venues of East Azerbaijan Province is equal to 10093.4 million Rials. Also, the interest return rate of the investment is equal to 19.43%. Therefore, using solar energy as a source of electricity production has technical and economic justification.
Supply chain management
Razieh keshavarzfard; Azam Naderi
Abstract
Approaches to the Vehicle Routing Problem (VRP) have been considered as a practical solution against increasing transportation costs in businesses. In fact, we seek to develop new methods to reduce shipping costs and at the same time maximize profits. Transportation of hazardous materials(HazMat), as ...
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Approaches to the Vehicle Routing Problem (VRP) have been considered as a practical solution against increasing transportation costs in businesses. In fact, we seek to develop new methods to reduce shipping costs and at the same time maximize profits. Transportation of hazardous materials(HazMat), as one of the most complex types of transportation, has always been studied and investigated by researchers. Designers of hazardous materials logistics networks should always design the routes between the hazardous materials’ production center and each of their collection centers, while considering the restrictions related to time windows and uncertainties related to them. In addition, they should take into account vehicle capacity and mileage capacity in sub-tours to minimize total transition and pollution costs. In this research a mathematical model is presented for vehicle routing of hazardous materials, simultaneously from three perspectives (economic, sensitivity of the route and the factors which cause uncertainty in the collection and delivery of hazardous materials). Afterwards, the hybrid Genetic and Simulated Annealing algorithm is applied as an optimization method to solve the problem. Finally, several numerical examples, as well as sensitivity analysis are provided to show the efficiency of the model. The results show as the route sensitivity coefficient increases, the objective function increases. The effect of demand on the objective function is generally upward, but in some cases it is downward.