stochastic/Probabilistic/fuzzy/dynamic modeling
Arezoo Khazaei; Parvaneh Samouei
Abstract
Purpose: The newsboy problem is one of the most widely used and important models in the field of inventory control. In fact, there are many industries whose products fall into the category of newosboy problem, such as seasonal goods, food products. But in practice there are more restrictions than the ...
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Purpose: The newsboy problem is one of the most widely used and important models in the field of inventory control. In fact, there are many industries whose products fall into the category of newosboy problem, such as seasonal goods, food products. But in practice there are more restrictions than the assumptions of the newsboy problem. In this article has tried, in order to make the problem more in line with the real world some limitations during production, such as outsourcing mode, capacity limit and returned goods, have been added to the problem.Methodology: This research is based on library studies and the development of mathematical modeling.Findings: In the newsboy problem, there are important parameters such as outsourcing, capacity constraints and product referral which in this study, the effect of each of these parameters on profitability has been evaluated.Originality/Value: Development of the newsboy problem in terms of outsourcing and returned products and capacity constraints.
Scheduling Modeling
Hamid Safarzadeh; Farhad Kianfar
Abstract
Purpose: Outsourcing is a prevalent strategy in the industry and business, which can enhance the performance of a company and rectify its constraints. This strategy can be integrated into various managerial aspects of a company, particularly the scheduling subject. In this paper, a single machine scheduling ...
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Purpose: Outsourcing is a prevalent strategy in the industry and business, which can enhance the performance of a company and rectify its constraints. This strategy can be integrated into various managerial aspects of a company, particularly the scheduling subject. In this paper, a single machine scheduling problem is investigated in which a set of jobs can be outsourced in a batch to a single subcontractor. It is supposed that the outsourcing time and cost of a job are proportional to its in-house processing time. In addition, a fixed logistics time and cost are also considered for the outsourcing batch. Moreover, the problem objective is to minimize the sum of the total completion time of the jobs and the total outsourcing cost.Methodology: To solve the problem, a set of optimal properties of the problem solution are proven via a lemma and a theorem to determine the optimal solution of the problem. Moreover, some computational experiments are also conducted at the end of the paper to examine the effect of the outsourcing strategy in the addressed problem.Findings: By the developed solution approach, the structure of the optimal solution is determined, using which the optimal solution of the problem can be chosen among a limited set of candidate solutions via some simple computations. Moreover, the computational results indicate the remarkable possible role of outsourcing in decreasing the value of the objective function of the problem.Originality/Value: In this paper, a new practical problem in the research area of scheduling with outsourcing is defined and its optimal solution is determined via a detailed analysis. Furthermore, using computational experiments it is shown that the outsourcing strategy can have a great role to attain the problem objectives.