A parameter-tuned genetic algorithm for vendor managed inventory model for a case single-vendor single-retailer with multi-product and multi-constraint

This paper develops a single-vendor single-retailer supply chain for multi-product. The proposed model is based on Vendor Managed Inventory (VMI) approach and vendor uses the retailer's data for better decision making. Number of orders and available capital are the constraints of the model. In this system, shortages are backordered; therefore, the vendor’s warehouse capacity is another limitation of the problem. After the model formulation, an Integer Nonlinear Programming problem will be provided; hence, a genetic algorithm has been used to solve the model. Consequently, order quantities, number of shipments received by a retailer and maximum backorder levels for products have been determined with regard to cost consideration. Finally, a numerical example is presented to describe the sufficiency of the proposed strategy with respect to parameter-tuned by response surface methodology (RSM).</p

Pricing and warranty decisions in a two-period closed loop supply chain

For a two-period closed loop supply chain (CLSC) consisting of a manufacturer and a retailer, Stackelberg game analyses are conducted to examine pricing and warranty decisions under two warranty models depending on who offers warranty for new and remanufactured products and the corresponding benchmark models with warranty for new products only. Next, we identify the conditions under which warranty for remanufactured products is offered and investigate how this warranty affects the CLSC operations. Subsequently, comparative studies are carried out to examine equilibrium decisions, profitability and consumer surplus of the CLSC between the two warranty models. Analytical results show that offering warranty for remanufactured products does not affect new product pricing in period 2, but influences pricing of new products in period 1 and remanufactured products in period 2, thereby enhancing remanufacturing, individual and channel profitability, and consumer surplus. Compared to the retailer warranty for remanufactured products, the manufacturer warranty can attain a more equitable profit distribution. If the warranty cost advantage of the manufacturer (retailer) is significant relative to that of the retailer (the manufacturer), the manufacturer (retailer) arises as a natural choice to offer warranty for remanufactured products as this decision enhances both profitability and consumer surplus

Three Essays on the Effect of Scarcity on Consumer Behavior and Firm Performance

Studies have consistently shown that scarcity plays a significant role in shaping decision making. Under conditions of scarcity, individuals tend to behave impulsively, and firms are inclined to redefine their set of priorities and strategies, ultimately impacting their performance. Considering the scant investigation of the mechanisms and effects of scarcity in the supply chain management literature, this dissertation aimed to investigate the roles of scarcity in shaping consumer behavior and firm strategy in three essays. The first essay investigated the effect of post-stockout scarcity disclosures on consumer responses to stockouts through the lens of product scarcity and signaling theory. The results of the experimental analysis indicate that post-stockout disclosures increase consumer perceived scarcity, reduce consumer satisfaction with the stockout situation, yet increase consumer purchase intention. However, the results of a time-effect analysis show that consumers\u27 perceived scarcity and purchase intention decrease over time when stockouts persist. These results indicate that effectively communicating the reasons for the stockout, as well as actions being undertaken for replenishing the product can serve as a powerful tool to retain customers exposed to stockouts. The second essay explored the role of retail product rationing (limit buys) in preventing stockpiling of essential products at retail stores during natural disasters through the lens of regret theory and anchoring effect. Results of an experimental investigation through manipulation of the number of items a consumer can buy and the presence/absence of disclosures highlighting social norms – or nudges, indicate that when consumers\u27 needs were less than the retailer\u27s set purchase limit, the purchase limit increased consumer stockpiling propensity. Additionally, though no significant effect of social nudges in the presence of a purchase quantity limit was found, social nudges significantly reduced consumer stockpiling propensity when no limits were placed. The third essay studied the effect of a firm\u27s financial and operational slack on its green supply chain management (GSCM) performance by using the natural resource-based view and conceptualizing slack as a capability needed by a firm to reach its green supply chain goals. Results of a random effect model analysis indicate that the firm\u27s absorbed slack and unborrowed slack (financial slacks), and capacity slack (operational slack) have a positive effect with diminishing returns on its GSCM performance. In contrast, inventory slack (a different kind of operational slack) has a negative effect with diminishing returns on a firm\u27s GSCM performance. Moreover, we found that the firm\u27s operating environment scarcity positively moderates the relationship between inventory slack and absorbed slack on GSCM performances GSCM performance. Environmental scarcity promotes a more efficient use of slack resources in the pursuit of green SCM efforts

Supply chain dynamics

Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2003.Includes bibliographical references (p. 121-123).The strong bargaining power of major retailers and the higher requirements for speed, service excellence and customization have significantly contributed to transform the Supply Chain Management. These increasing challenges call for an integrated and dynamic Supply Chain Management and for a better integration and alignment with key customers, in order to reduce the firm's time-to-market and build competitive advantage. The thesis aims at providing the partner company, a major player in the consumer goods industry, with a more robust and efficient vendor managed inventory practice, so that the partner can determine the optimum inventory level to satisfy turnover, service level and lead time requirements, whereas minimizing lost sales and total costs in the system. The team developed a Supply Chain Dynamics framework to help the partner to establish new service level strategies, strongly oriented to the strategic importance of its products and customers, and to map the key system-wide drivers that impact the overall number of inventory turns, service level and total costs. Additionally, in order to run simulations and estimate the outcomes of the proposed recommendations, the team developed a "Multi-Echelon" simulator and used a commercial "Supply Chain Dynamics" simulator.by Ricardo Wagner Lopes Barbosa [and] Edward Fan.M.Eng.in Logistic

Discounting and dynamic shelf life to reduce fresh food waste at retailers

Approximately 89 million of tonnes of food is wasted every year in the EU along the whole food supply chain. The reasons for food waste by retailers include inappropriate quality control, overstocking and inaccurate forecasting. This study shows that food wasted by retailers can be reduced by discounting old products or by applying a dynamically adjustable expiration date (in other words dynamic shelf life (DSL)). We developed a simulation based optimization model to optimize the replenishment and discounting policy of a retailer who sells meat products. DSL outperforms a fixed shelf life (FSL) in terms of profit, waste, shortages and food safety. Furthermore, replenishment quantities can be higher. The benefits of DSL are greater when demand is low or when the shelf life of products is short. Discounting is a successful strategy to reduce food waste for both FSL and DSL. DSL without discounting is more effective than FSL with discounting. Combining DSL and discounting, allows for a further reduction of food waste.</p

Modelling, simulation, and analysis of supply chain systems using discrete-event simulation.

Many approaches have been developed which support the construction of detailed supply chain models useful for analysis and simulation. However, most of these approaches lack the ability to model the supply chain in a single model, and usually produce solutions that lead to conflicting strategies between the companies. Simulation using a discrete-event simulation (DES) is an effective tool for the dynamically changing supply chain variables, thus allowing the system to be modelled more realistically. Considering the complexities of the supply chain system and the interrelations between its various systems, the task of developing such a model is challenging. The aim of this thesis is to develop a simulation model of a fast moving consumer goods (FMCG) supply chain with a DES tool. This model would be utilised as a decision-support system (DSS) for the investigation of the effectiveness of several inventory policies towards effective coordination and control of production inventory system, in various situations. This thesis discusses fundamental issues in the development of a simulation model for a supply chain using the DES tool, ARENA. A modelling procedure for the development of a supply chain simulation model is presented. The overall structure of the model is constructed by incorporating the well documented concept of modelling materials flowing downstream with an approach of modelling orders flowing upstream (modelling of feedback information). The model has an easily adaptable structure where rules (inventory policies) and model variables can be modified. The flexibility in the model's structure allows devising appropriate experimental designs, for several tests to be performed to imitate some realistic situations or scenarios (including the presence of disturbances). A new control theory oriented inventory policy, called the pseudo PID, is proposed. Detailed evaluations of five inventory policies for a production-inventory control under dynamic and stochastic conditions is presented. The findings demonstrate the ability of the approach to provide a wealth of potential solutions to the decision-maker, and confirm the qualitative behaviour of a supply chain in response to the different policies

Efficient Remedies for Breach of Warranty

This article attempts to suggest valuable refinements and extensions of the economic theory of warranty by explicitly considering the choice of remedies for breach of warranty in conjunction with the choice of warranty protection itself. In particular, it offers explanations for the prevalence of replacement terms rather than refund terms in warranties. Economists studying the general issue of breach of contract have noted that the choice of remedy has important implications for risk sharing, renegotiation, transaction-specific investment, and the incentive to breach.5 This article derives much of its insight from the recognition that work on the economics of contract breach has much to say that is relevant to the economics of warranties

Optimal trade credit and lot size policies in economic production quantity models with learning curve production costs

[[abstract]]In reality, a seller (e.g., a supplier or a manufacturer) frequently offers his/her buyers trade credit (e.g., permissible delay in payment). Trade credit reduces the buyer's holding cost of inventory and hence attracts new buyers who consider it to be a type of price reduction. On the other hand, granting trade credit also increases the seller's opportunity cost (i.e., the loss of capital opportunity during the credit period) and default risk (i.e., the event in which the buyer will be unable to make the required payments on his/her debt obligation). In addition, it is a well-known fact of learning-by-doing that production cost of a new product declines by a factor of from 10 to 50 percent each time the accumulated production volume doubles. Therefore, we propose an economic production quantity model from the seller's prospective to determine his/her optimal trade credit period and production lot size simultaneously in which (i) trade credit increases not only sales but also opportunity cost and default risk, and (ii) production cost declines and obeys a learning curve phenomenon. Then the necessary and sufficient conditions to obtain the seller's optimal trade credit and order quantity are derived. Finally, we use some numerical examples to illustrate the theoretical results and to provide some managerial insights.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子