International Journal of Industrial Engineering & Production Research

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Planning and design procedure of an open pit mining project just can be started after ultimate pit determination. In the carried out study in this paper it was shown that the most important factor in ultimate pit determination and in consequence in the whole planning and design procedure of an open pit mine is the metal price. Metal price fluctuations in recent years were exaggerated and imposed a high degree of uncertainty to the mine planning procedure while none of the existent algorithms of the pit limit determination consider the metal price uncertainty. Real Option Approach (ROA) is an efficient method of decision making in the condition of uncertainty. This approach usually used for evaluation of defined natural resources projects up to now. This study considering the metal price uncertainty used real option approach to prepare a methodology for determining the Ultimate Pit Limits (UPL). The study was carried out on a non-ferrous metallic cylindrical ore deposit but the achieved methodology can be adjusted for all kinds of the deposits. The achieved methodology was comprehensively described through the examples in a way that can be used by the mine planners.

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  For any organization sound marketing strategy and quality assurance play vital role in the growth of the organization. The price, quality and service, service centers, friendly attitude, Discounts on sales, esthetics, store location and appearance, ease of operations, guarantees and warranties, adopting new ideas, and flexible payments terms were considered to study the perceptions of the respondents. The ultimate aim is to uphold the turnover of the organization and to create good market penetration of the goods produced in highly competitive business world .

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It was suggested in 2004 by some researchers that it might be possible to improve production systems performance by applying the first and second laws of thermodynamics to reduce system entropy. Then these laws were used to modify the economic order quantity (EOQ) model to derive an equivalent entropic order quantity (EnOQ). Moreover the political instability or uncertainty of a country (as well as the whole world) leads to a much more unstable situation in the present world economy. Thus, changes in inflation take place, and it is needed to consider uncertain inflation rate. In this paper we extend the EnoQ model by considering deteriorating items with imperfect quality and price dependent demand. We also assume fuzzy inflation and discount rates.‌ A mathematical model is developed to determine the number of cycles that maximizes the present value of total revenue in a finite planning horizon. The fuzzified model for inflation and discount rate is formulated and solved by two methods: signed distance and fuzzy numbers ranking. Numerical examples are presented and results are discussed. Results show that the number of cycles decreases in fuzzy inflationary conditions. They also illustrate that defuzzification method results in more cycles than fuzzy method.

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We model a real-world case problem as a price competition model between two leader-follower supply chains that each of them consists of one manufacturer and one retailer. T he manufacturer produces partially differentiated products and sells to market through his retailer. The retailer sells the products of manufacturer to market by adding some values to the product and gains margin as a fraction of the all income of selling products. We use a two-stage Stackelberg game model to investigate the dynamics between these supply chains and obtain the optimal prices of products. We explore the effect of varying the level of substitutability coefficient of two products on the profits of the leader and follower supply chains and derive some managerial implications. We find that the follower supply chain has an advantage when the products are highly substitutable. Also, we study the sensitivity analysis of the fraction of requested margin by retailer on the profit of supply chains.

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Abstract

            In this research, an integrated inventory model for non-instantaneous deteriorating items is analyzed when demand is sensitive to changes in price. The price used in this research is a time-dependent function of the initial selling price and the discount rate. To control the deterioration rate of items at the storage facility, investment in preservation technology is incorporated. To provide a general framework to the model, an arbitrary holding cost rate is used. Toward the end of the paper, a numerical case is given to approve the model and the impacts of the key parameters of the model are studied by sensitivity analysis to deduce managerial insights.

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Nowadays, competitive market creates the necessity of quality improvement in different levels of supply chains (SCs). This paper contributes to the SC coordination literature and proposes a bilateral coordination contract for optimizing pricing decisions along with quality improvement decisions in different echelons of a real case of a cell phone SC. The SC comprises a manufacturer who deals with determining the product quality, and a retailer who seeks for the optimal strategy on price, after-sale service and service level in a periodic review inventory system. The proposed bilateral wholesale price (BWP) contract is shown to be capable of simultaneous coordination of these decisions. The sensitivity analysis showed that in a market which is sensitive to quality and after-sale service as well as the product price, the proposed model facilitates investing more in such quality improvements while the members’ profitability with respect to the case without contracts is guaranteed. Moreover, it can increase the SC service level since it enables the members to hold more safety stock even under high inventory costs. Overall, the proposed coordination model on pricing, product quality, after-sale service and service level, leads to the optimal performance of the SC and its members while it is beneficial for the customers.

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In this research, we analyze a supply chain involving two competing manufacturers that sells their product through two common competing retailers. The manufacturers’ products are the same but with different brand in market. The retailers face stochastic demand where demand is a decreasing function of price with additive uncertain part. Manufacturers compete on supplying orders where retailers compete on selling price. Each manufacturer set wholesale price contract with retailers similarly. We examine supply chain coordination with wholesale price contract under competition and demand uncertainty. The analytical results show that under coordination condition, manufacturers do not obtain any positive profit and consequently the retailers intend to increase wholesale prices. On the other hand, manufacturers can increase wholesale prices until the retailers’ profit becomes zero. Hence, with a numerical study for actual cases, it is found that changing demand sensitivity and competition intensity affect the optimal decisions of ordering and pricing. Moreover, increasing in competition sensitivity, increase the supply chains’ efficiency, stocking level and selling price. The concluding remarks show that further investigation is required for possibility of coordination under competition by other contractual mechanisms.