Qiuhong Zhao

Beihang University (BUAA) | BUAA · Department of Management Science and Engineering

Currently, an increasing number of firms have begun to outsource production to/from firms that compete in common markets. This work shows the dual roles of inter-competitor outsourcing: it can improve both firms’ profits and alleviate conflicts between them in product launching time. Specifically, we establish an analytical model in which an origin...

When disaster relief is executed by a monopolistic emergency management agency, this entity is responsible for the procurement and storage of relief goods in the given area. In the case of extreme disasters, relief goods are generally donated to the affected area from all over the world, but the delivery of these donations normally takes time. To e...

Perishable raw materials are commonly used in people's daily life. However, some of the raw materials' perishability, such as fruits and milk, raises a vital concern in food supply chain during transportation, processing, storage and sales. In this study, we propose a novel sourcing-production-inventory (SPI) system considering single manufacturer...

In recent years, an increasing number of competing firms have started to integrate their product attribute development and advertising strategies by targeted advertising of the best-developed attribute of their product. With a focus on such integration and its potential effects, we establish an analytical model in which two competing firms sell mul...

Nowadays, the brown products are losing market coverage to their green alternatives due to consumers' increasing environmental awareness. Confronted with this threat, many traditional manufacturers currently producing only brown product are contemplating the launch of green product. Base on this background, this paper explores the optimal product c...

In some spare parts distribution systems for consumption goods, a portion of consumers’ demand is met by inventories in maintenance outlets, while the remaining portion is satisfied with emergency orders from the supplier, which can enhance customers’ satisfaction but cause added order‐processing costs and transportation costs. Faced with the trade...

A sequential game model is built to analyze the interaction between the government’s effort in safety regulation and the company’s safety effort based on the case in China. An equilibrium solution for the game model is given, and a theoretical analysis concerning the impact of the governments’ regulation on the solution is illustrated. The results...

The purpose of this paper is to formulate a retailer-supplier uncooperative replenishment model with demand and default risk are functions of the trade credit period for determining the optimal trade credit period in a supplier-Stackelberg game. Firstly, we present optimal results for the decentralized decision and the centralized decision without...

In the paper, an uncooperative replenishment schedule with variable trade credit is considered under a supplier-Stackelberg game, which considers time-varying demand with time-varying price and learning curve production cost for the finite planning horizon in a two-echelon supply chain. We focus on discussing which condition induces the retailer an...

The purpose of the paper is to formulate two uncooperative replenishment models with demand and default risk which are the functions of the trade credit period, i.e., a Nash equilibrium model and a supplier-Stackelberg model. Firstly, we present the optimal results of decentralized decision and centralized decision without trade credit. Secondly, w...

Regions often cooperate with each other in emergency rescue efforts, often times maintaining the principle of territorial priority. In this paper, a regional cooperation-based relief warehouse location model is constructed that takes into consideration the principle of territorial priority. The objective of the model is to minimize the maximum expe...

This paper analyzes the factors influencing safety investment decisions by the government and enterprises from an opportunity cost perspective, which consists of shortage cost due to the occurrence of accidents and excess cost due to investing more than required for accident prevention. Analytical models are built by minimizing expected total oppor...

China is one of the countries suffering from the most disasters in the world, so national emergency warehouse location is critical for the country to reduce loss resulting from disasters. Considering that emergency management is more concerned about effectiveness than efficiency, the paper proposes an emergency warehouse location problem (EWLP) mod...

In this study, we investigate the problem of maximum frequent time-window selection (MFTWS) that appears in the process of discovering association rules time-windows (ARTW). We formulate the problem as a mathematical model using integer programming that is a typical combination problem with a solution space exponentially related to the problem size...

The purpose of the paper is to formulate a collaborative mechanism for optimising the replenishment schedule under trade credit and shelf-life constraint in a two-echelon supply chain. We first derive the necessary and sufficient conditions to obtain the optimal replenishment policy for the non-integrated and collaborative scenarios, respectively....

In this study, we improved the variable neighborhood search (VNS) algorithm for solving uncapacitated multilevel lot-sizing (MLLS) problems. The improvement is twofold. First, we developed an effective local search method known as the Ancestors Depth-first Traversal Search (ADTS), which can be embedded in the VNS to significantly improve the soluti...

This article presents the variable neighbourhood simulated annealing (VNSA) algorithm, a variant of the variable neighbourhood search (VNS) combined with simulated annealing (SA), for efficiently solving capacitated vehicle routing problems (CVRPs). In the new algorithm, the deterministic ‘Move or not’ criterion of the original VNS algorithm regard...

In this paper, a nonintegrated and collaborative replenishment policy is considered, respectively, which incorporates varying demand depending on both inventory level and time during the finite planning horizon. For additional cost savings realized from coordination, the paper adopts trade credit as a cost-saving shift means and introduces a brand...

This paper investigates the impact of partial information sharing in a three-echelon supply chain. Partial information sharing means that information sharing occurs only between the distributor and the retailer, but not between the distributor and the manufacturer. This paper contributes to the literature by summarizing the circumstances in which i...

Contemporary quality management studies describe a range of quality improvement strategies. However, these studies do not consider the impact of quality management practices on the knowledge creation process. Based on a comprehensive literature review and a field survey, this study investigates the impact of quality management practices on the know...

Emergency incidents, including natural disasters, terrorist attacks, public health outbreaks, and industrial and mining accidents, and so forth, result in severe human casualties and property losses. Emergency facilities, which provide relief materials and services, play an important role in rescue management. The decision of where to locate the em...

The incorporation of the minimization of carbon dioxide (CO2) emissions in the VRP is important to logistics companies. The paper deals with the tractor and semitrailer routing problem with full truckload between any two depots of the network; an integer programming model with the objective of minimizing CO2 emissions per ton-kilometer is proposed....

The multi-level capacitated lot-sizing problem (MLCLSP) has been an important part of material requirement planning (MRP) system. In this paper we combine variable neighborhood decomposition search and accurate mixed integer programming (VNDS-MIP) to solve MLCLSP. This method is based on the variable neighborhood search, and with the use of exact L...

In this paper, we studied the problem of maximum frequent time-window selection (MFTWS) that appears in the process of discovering frequent itemset with time-windows (FITW). We formulated this problem as an integer programming mathematical model that is a typical combination problem with a solution space exponentially related to the problem size. A...

Fuel consumption accounts for a large and increasing part of transportation costs. In this paper, the Fuel Consumption Rate (FCR), a factor considered as a load dependant function, is added to the classical capacitated vehicle routing problem (CVRP) to extend traditional studies on CVRP with the objective of minimizing fuel consumption. We present...

In this paper, several neighborhood search techniques for solving uncapacitated multilevel lot-sizing problems are investigated. We introduce three indexes: distance, changing range, and changing level that have great influence on the searching efficacy of neighborhood search techniques. These insights can help develop more efficient heuristic algo...

The paper considers the application of a modified policy iterative algorithm for the integrated optimization problem of the location and inventory decisions of a distribution center (DC), constrained by given customer service levels in a multi-product multi-echelon supply chain, which is formulated as an integrated optimization model based on a Mar...

In the traditional inventory decision-making, demand forecasting and inventory control decisions are made independently, so it is difficult to ensure that the inventory cost is minimized. To make the demand forecasting and inventory control be consistent, this paper proposes a cost regression model, in which the demand forecasting is combined with...

Multilevel lot-sizing (MLLS) problems, which involve complicated product structures with interdependence among the items, play an important role in the material requirement planning (MRP) system of modern manufacturing/assembling lines. In this paper, we present a reduced variable neighborhood search (RVNS) algorithm and several implemental techniq...

The supply chain considered includes one supplier and one retailer. Each of them adopts long-term strategy, i.e., they maximize their own sum of profit in a two-period decision horizon. The model assumes that the estimation of distribution of the demand can be updated over time via the realization of sales. The optimal strategies for both supplier...

This paper studies a multi-product competitive newsboy problem with shortage penalty cost and partial product substitution. We characterize the unique Nash equilibrium of the competitive model and analyze some properties of the equilibrium. An iterative algorithm is developed on the basis of approximating the effective demand as well as the expecte...

In some retail contexts, displaying large quantities of inventory may stimulate demand. Manufacturers are therefore continuously battling for the retailer's limited shelf space. This paper models the impact of inventory subsidy contracts on the competition between manufacturers. Consider a supply chain with two competing manufacturers and their com...

This paper analyzes the transshipment operations in a dual-channel supply chain, which includes a traditional retail channel and an online direct channel. Previous study has shown that the implementation of transshipment among integrated firms can improve the revenue and customer service level, and also reduce the quantity of inventory. But in the...

In this paper, an effective approach based on the variable neighborhood search (VNS) algorithm is presented to solve the uncapacitated multilevel lot-sizing (MLLS) problems with component commonality and multiple end-items. A neighborhood structure for the MLLS problem is defined, and two kinds of solution move policies, i.e., move at first improve...

This paper considers the application of a variable neighborhood search (VNS) algorithm for finite-horizon (H stages) Markov Decision Processes (MDPs), for the purpose of alleviating the “curse of dimensionality” phenomenon in searching for the global optimum. The main idea behind the VNSMDP algorithm is that, based on the result of the stage just c...

This paper addresses some of the challenges faced by a company which is responsible for delivering coal to its four subsidiaries situated along a river, through river hired or self-owned vessels. We propose to adopt a vendor managed inventory concept that involves establishment of a central warehouse at the port, and apply the Markov Decision Proce...

The substitution between products is a common phenomenon in supply chains when customers find their favorite product unavailable. Products substitution can improve the availability of products and further enhance the quick response ability of supply chains, especially when the products are perishable. In this chapter, a single-period newsboy framew...

In this paper we propose a simple but efficient modification of the well-known Nelder–Mead (NM) simplex search method for unconstrained optimization. Instead of moving all n simplex vertices at once in the direction of the best vertex, our “shrink” step moves them in the same direction but one by one until an improvement is obtained. In addition, f...

B2B online exchange has provided manufacturers and retailers an alternative outlet to trade commodity or service. Some manufacturers and retailers began to participate in the B2B online exchange. According to whether the manufacturer and the retailer participating in the B2B online exchange or not, four different channel structure appears. This pap...

This paper considers a two-level vendor managed inventory (VMI) system comprising a distribution center (DC) and a retailer. Both the DC's and the retailer's replenishment decisions follow the order-up-to-level policy and aim at maximizing the profit of the overall system. We critically examine the potential of the DC's ability to modify delivery d...

This paper addresses an integrated inventory and routing problem in a three-echelon logistics system, which consists of a supplier, a central warehouse and a group of retailers. The inventory decision of each member and the routing decision among members of the system are made simultaneously, with the objective of minimizing the overall average cos...

In this study we focus on the integration of inventory control and vehicle routing schedules for a distribution system in which the warehouse is responsible for the replenishment of a single item to the retailers with demands occurring at a specific constant (but retailer-dependent) rate, combining deliveries into efficient routes. This research pr...

In this paper, we address the problem of deciding the optimal ordering quantity and frequency for a supplier–retailer logistic system in which the transportation cost as well as the multiple uses of the vehicles are considered. Based on the traditional economic order quantity (EOQ) formula, a modified EOQ model is set up and an algorithm for the mo...

A study of the vehicle transportation system for a manufacturer is presented. An algorithm based on a dynamic programming model is developed so as to find the optimal transportation arrangements referring to the composition of the vehicles as well as the routing of these vehicles. The algorithm is run under the current condition as well as under a...

In this paper, we address the problem of evaluating the benefits of considering the multiple use of a set of homogeneous vehicles in the routing problem. Based on a mixed-integer linear programming model, a Tabu Search (TS) algorithm was presented for the multiple-trip vehicle routing problem. Further discussion shows that the multiple use of the v...

In this paper we present a multi-period dynamic programming (DP) model for vehicle composition problems on fixed routes with transshipment points. An exact algorithm is developed for the DP model. Based on some of the problem’s structural properties, the optimal solution can be gained with reduced computational complexities. A few cases are given t...

In this study we focus on the integration of inventory control and vehicle routing schedules for a distribution system in which the warehouse is responsible for the replenishment of a single item to the retailers with demands occurring at a spe- cific constant (but retailer-dependent) rate, combining deliveries into efficient routes. This research...