Improving Profitability of a Color Production Line by Breaking Down Bottlenecks: A Computer Simulation Approach

Bottlenecks are one of the controversial issues in manufacturing companies. Managers and designers attempt to manage this trouble to improve efficiency in different ways. For example, expanding capacity is a prevalent solution to get rid of bottlenecks. In this paper, a color production line is chosen, which faces several challenges in its production line. This company attempts to distinguish and diminish the bottlenecks in the production line. The objective of this paper is to build a developed model of a production line to improve its profitability by breaking down its bottlenecks. Besides, the optimum number of operators with different utilizations is investigated in this paper. Furthermore, we considered the construction of new quality control in the station, which is the most time-wasting operation in the production line. The current study aims to apply computer simulation to examine the production line bottlenecks. In doing so, arena 14.00 software is used. Then the results are analyzed, and several managerial implications are presented.Comment: 10 page

Developing a new stochastic competitive model regarding inventory and price

Within the competition in today's business environment, the design of supply chains becomes more complex than before. This paper deals with the retailer's location problem when customers choose their vendors, and inventory costs have been considered for retailers. In a competitive location problem, price and location of facilities affect demands of customers; consequently, simultaneous optimization of the location and inventory system is needed. To prepare a realistic model, demand and lead time have been assumed as stochastic parameters, and queuing theory has been used to develop a comprehensive mathematical model. Due to complexity of the problem, a branch and bound algorithm has been developed, and its performance has been validated in several numerical examples, which indicated effectiveness of the algorithm. Also, a real case has been prepared to demonstrate performance of the model for real world

A sustainability approach to vehicle modular platform design: A mathematical model

Today, sustainability and its economic, social, and environmental pillars are the main elements of new product market development. Therefore, manufacturers, considering all stages of a product life-cycle, consider it necessary to have a framework for producing sustainable products. Moreover, new product design and development processes especially sub-process of product definition and detailed design processes can play a very critical role in developing product sustainability. This paper considers the role that the car platform can play in creating a family of products and with regard to various data related to the environmental, economic, and social pillars of each of the 15 modules of a car platform and also, using the best–worst method technique and multi-objective mathematical programming with the augmented epsilon constraint method, we were able to achieve a set of platforms with maximum sustainability. The present study explores the possibility of determining the most efficient combinations of modules for every one of the 23 cars’ platforms to produce a collection of products. Through these methods, the 54 efficient solutions in the Pareto front were achieved, and out of this number, after considering all the factors and weights of the objective functions, solution no. 51 was selected as the most efficient. Subsequently, all the 15 module variants of the 23 platforms were determined for solution no. 51. Finally, these variants were ranked on the basis of the SAW technique, and finally, sensitivity analysis is done

Multi-objective routing and scheduling for relief distribution with split delivery in post-disaster response

Abstract Following the occurrence of unexpected events and natural disasters, a highly important relief operation is the transferring of relief commodities from the distribution centers (DCs) to shelters. In this paper, a three-level network consisting of depot of vehicles, distribution centers,and shelters has been considered for routing and scheduling of relief vehicles through introducing a multi-objective model. The first objective function represents the total arrival time of vehicles to DCs and shelters. The second objective function illustrates the number of vehicles used. We use the TH method to deal with the multi-objective problem. During the relief commodities distribution, issues such as the feasibility of getting service from each distribution center with multiple vehicles and heterogeneous fleet of vehicles has been regarded. In order to solve the proposed model and represent its efficiency, we select the fourth region of Tehran city as a case study; run the model on it, and present solution results. Keywords: Disaster Management, Multi-objective optimization, Routing, Scheduling 1-Introduction The occurrence of natural and man-made disasters such as flood, earthquake, thunderstorm, etc. would cause drastic social and economic damages, as well as the displacement and even the death of thousands of people. Accordingly, in order to lower the casualties and economic losses in these disasters, certain relief operations should be considere

Enhancing Sustainability Attributes in New Product Design Insights from Automotive Industry

Product design is an innovative process that, through the stages of problem statement, concept, and initial and detailed design, meets the needs of customers, the requirements of companies, and their limitations. In the current process of product design and development, formulating design objectives plays a crucial role in objective setting, project implementation, product needs and requirements specification, and performing activities validation. Currently, the role of the design and development stages in the sustainability of products, identifying strategies for improving this stage is of particular significance, and paying attention to the product planning and definition process group and focusing on establishing sustainability principles in the target book and defining new attributes can be regarded as one of the sustainable product development strategies. Consequently, this research is a case study in the field of applying the sustainability principles in the target book as one of the deliverables at the stage of product planning. The present study proposes strategies towards developing the attributes of the target book as a tool for exerting sustainability pillars in the process of design and development by means of surveying automotive industry experts, applying the DEMATEL and Fuzzy ANP combined method, and evaluating and determining new attributes

Designing reliable supply chain network with disruption risk

Although supply chains disruptions rarely occur, their negative effects are prolonged and severe. In this paper, we propose a reliable capacitated supply chain network design (RSCND) model by considering random disruptions in both distribution centers and suppliers. The proposed model determines the optimal location of distribution centers (DC) with the highest reliability, the best plan to assign customers to opened DCs and assigns opened DCs to suitable suppliers with lowest transportation cost. In this study, random disruption occurs at the location, capacity of the distribution centers (DCs) and suppliers. It is assumed that a disrupted DC and a disrupted supplier may lose a portion of their capacities, and the rest of the disrupted DC's demand can be supplied by other DCs. In addition, we consider shortage in DCs, which can occur in either normal or disruption conditions and DCs, can support each other in such circumstances. Unlike other studies in the extent of literature, we use new approach to model the reliability of DCs; we consider a range of reliability instead of using binary variables. In order to solve the proposed model for real-world instances, a Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is applied. Preliminary results of testing the proposed model of this paper on several problems with different sizes provide seem to be promising

A mathematical model for vehicle routing and scheduling problem with cross-docking by considering risk

Today, many companies after achieving improvements in manufacturing operations are focused on the improvement of distribution systems and have long been a strong tendency to optimize the distribution network in order to reduce logistics costs that the debate has become challenging. Improve the flow of materials, an activity considered essential to increase customer satisfaction. In this study, we benefit cross docking method for effective control of cargo flow to reduce inventory and improve customer satisfaction. Also every supply chain is faced with risks that threaten its ability to work effectively. Many of these risks are not in control but can cause great disruption and costs for the supply chain process. In this study we are looking for a model to collect and deliver the demands for the limited capacity vehicle in terms of disruption risk finally presented a compromised planning process. In fact, we propose a framework which can consider all the problems on the crisis situation for decision-making in these conditions, by preparing a mathematical model and software gams for the following situation in a case study. In the first step, the results presented in mode of a two-level planning then the problem expressed in form of a multi-objective optimization model and the results was explained

Warehouse redesigning in a three-echelon supply chain network with consideration of routing under uncertainty: A light robust approach

This paper addresses the problem of redesigning a three-echelon supply chain network under uncertainty. Since one of the most realistic problems that supply chains are dealt with is routing of vehicles, routing constraints with a split delivery condition are considered in our proposed model. Also, the possibility of outsourcing is considered in order to satisfy demands that exceed the production capacity. Furthermore, in order to deal with the presence of uncertainty in the problem, a light robust approach is developed. The performance of the proposed model is illustrated using a simulation procedure. Sensitivity analysis on the proposed model is also presented in the paper. The results show that the proposed method has a better performance than Light Robust approach and can be used as a useful managerial tool in redesign problems

Risk Assessment and Ranking through Integration Failure Mode and Effects Analysis and Multiple-Criteria Decision-Making in an Interval Valued Fuzzy Environment: A Case Study in Hydraulic Pump Industry

Background and Objective: Nowadays with the increase of global competition, companies apply several scientific methods to identify, assess, and remove potential failures in the production process. In this regard, the present study aimed to identify and analyze the potential failure modes in a hydraulic pump manufacturing company by using a combination of interval valued fuzzy analytic network process (IVF-ANP), interval valued fuzzy failure mode effect and analysts (IVF-FMEA), and interval valued fuzzy TOPSIS (IVF-TOPSIS). Materials and Methods: For the purposes of the study, first, the potential failure modes of the production process were identified using the opinion of experts. Then, the failure modes were prioritized based on the proposed method. The proposed approach applied the IVF-ANP to determine the weight of each risk assessment factor and a combination of IVF-FMEA and IVF-TOPSIS to rank the potential failure modes. Results: In total, 30 failure modes were identified in the present study. The highest-ranking failure mode was inappropriate feed rate with a relative closeness of 0.83. On the other hand, the lowest-ranking failure mode was the large size of the bush with a relative closeness of 0.015. Conclusion: The results showed that the proposed approach is applicable for the assessment and ranking of failure modes. In addition, consideration of some issues like the cost, interdependence of risk assessment factors, and also modeling the method under the condition of interval valued fuzzy uncertainty, affected the final ranking of failure modes

A hybrid lexicographic and VIKOR approach for prioritizing construction projects by considering sustainable development criteria

Nowadays, one of the challenges in the organizations according to budget limitations in the com-panies, is how to prioritize their project portfolios in the events of their strategies. In other words, organizations are seeking to allocate resources in order to gain the maximum profit ac-cording to budget limitations. In this article, a hybrid decision making method is used to priori-tize construction project portfolio by considering sustainability criteria. First, Lexicographic method is applied to weight the sustainability criteria. Then, by considering the weights derived from the Lexicographic and sustainability criteria, projects are prioritized based on VIKOR method. The proposed method of this study is applied for a case study of projects in the refinery scope