氏名　UDDIN MOHAMMED FORHAD
学位の種類　博士（工学）
学位記番号　博甲第633号
学位授与の日付　平成24年8月31日
学位論文題目　Supply Chain Optimization and Coordination in Vendor Buyer Systems　（供給者と需要者の調整を考慮したサプライチェーンの最適化）
論文審査委員
　主査　准教授　佐野　可寸志
　副査　教授　李　志東
　副査　准教授　樋口　秀
　副査　東京工業大学　大学院　准教授　花岡　伸也
　副査　鳥取大学　大学院　准教授　土屋　哲

• 論文目次
• 論文要旨
• 論文審査の結果の要旨

［平成24（2012）年度博士論文題名一覧］ ［博士論文題名一覧］に戻る．

Contents　page
Chapter 1:　INTRODUCTION
　1.1　Introduction　p.1
　1.2　Problem Statement　p.3
　1.3　Research Objectives　p.6
　1.4　Scope of the Dissertation　p.6
　1.5　Structure of the Thesis　p.8
Chapter 2:　LITERATURE REVIEW　p.10
　2.1　Introduction　p.10
　2.2　Coordination and Supply Chain Optimization　p.10
　2.2.1　Quantity Discount Models　p.11
　2.2.2　Joint Economic Lot Sizing Models　p.13
　2.2.3　Price Sensitive Models　p.14
　2.2.4　Integrated Models　p.14
　2.2.5　Models with Economic Factors　p.17
Chapter 3:　CONVEPTUAL FRAMEWORK　p.18
　3.1　Introduction　p.18
　3.2　Overview of Methodology Framework　p.18
　3.2.1　Vendor-Buyer Coordination and Supply Chain Optimization with Deterministic Demand Function　p.21
　3.2.2　Vendor-Buyer Coordination and Supply Chain Optimization with Linear Demand Function　p.21
　3.2.3　Vendor-Buyer Coordination, Integration and Supply Chain Optimization with Non-linear Demand Function　p.22
　3.2.4　Implementation of Coordination and Supply Chain Optimization in Real World Case　p.22
Chapter 4:　VENDOR-BUYER COORDINATION AND SUPPLY CHAIN OPTIMIZATION WITH DETERMINISTIC DEMAND FUNCTION　p.24
　4.1　Introduction　p.24
　4.2　Model Formulation　p.25
　4.2.1　Mixed Integer Linear Fractional Program　p.26
　4.2.2　Notations and Assumptions　p.28
　4.2.3　Prerequisites of the Objective Function　p.29
　4.2.4　MILFP Model　p.31
　4.2.5　MIP Model　p.32
　4.3　Solution Approach　p.33
　4.4　Computational Analysis　p.34
　4.5　Conclusion　p.41
Chapter 5:　VENDOR-BUYER COORDINATION AND SUPPLY CHAIN OPTIMIZATION WITH LINEAR DEMAND FUNCTION　p.42
　5.1　Introduction　p.42
　5.2　Notations, Assumptions and Model Formulation　p.44
　5.2.1　Buyer's Model　p.46
　5.2.2　Vendor's Model　p.47
　5.2.3　Coordinated Model　p.48
　5.3　Numerical Example and Solution Approach　p.49
　5.4　Result Analysis　p.50
　5.5　Conclusion　p.56
Chapter 6:　VENDOR-BUYER COORDINATION AND SUPPLY CHAIN OPTIMIZATION WITH NON-LINEAR DEMAND FUNCTION　p.57
　6.1　Introduction　p.57
　6.2　Notations, Assumptions and Model Formulation　p.59
　6.2.1　Buyer's Model Formulation　p.60
　6.2.2　Vendor's Model　p.61
　6.2.3　Coordinated Joint Model　p.63
　6.3　Solution Procedure of the Coordinated Joint Model　p.64
　6.4　Numerical Example and Results Discussion　p.65
　6.5　Conclusion　p.71
Chapter 7:　IMPLEMENTATION OF COORDINATION AND SUPPLY CHAIN OPTIMIZATION IN REAL WORLD CASE　p.72
　7.1　Introduction　p.72
　7.2　Model Formulation　p.74
　7.2.1　Coordination of Factors for Production and Consumption　p.74
　7.2.2　Coordination and Commodity Distribution　p.75
　7.3　Data Collection　p.77
　7.3.1　Tokyo Metropolitan Goods Movement Survey　p.77
　7.3.2　Basic Survey of Human Resources Development　p.80
　7.3.3　Establishment and Enterprise Census　p.81
　7.3.4　Other Basic Survey　p.83
　7.4　Result Analysis　p.86
　7.4.1　Coordinated Commodity Production and Consumption　p.86
　7.4.2　Coordination and Commodity Distribution　p.100
　7.5　Conclusion　p.108
Chapter 8:　CONCLUTIONS AND RECOMMENDATIONS　p.110
　8.1　Conclusions　p.110
　8.1.1　Coordination and Optimization Approach　p.110
　8.1.2　Application of Coordination Mechanism　p.111
　8.2　Recommendations for Further Studies　p.112
REFERENCES　p.113
APPENDIX A　p.121
　A.1　Concavity of Buyer's Profit Function　p.121
　A.2　Concavity of the Coordinated Joint Model　p.122
　A.3　Fraction of Commodity Purchased by Buyer Firm from Vendor Firm　p.122
　A.4　Characteristics of Survey Data　p.124

Supply Chain Management （SCM） has the difficulties for the disconnected and independent economic individuals. Various companies have realized the potential for achieving a competitive advantage through effectively coordinating different logistics members in the supply chain. At present, supply chain is confronted with rapid technological changes and high competitiveness. The companies are more successful that could respond to the customer’s needs effectively, regarding the existing opportunities and threats. A supply chain consists of various organizations that have permitted companies to successfully operate a collaboratively, it can satisfy customer’s demand, only when the whole of its parties become integrated and coordinated. An important issue in SCM is to develop mechanisms that can align their objectives and coordinate their activities to optimize the performance of the supply chain.

In this dissertation, a supply chain with coordination mechanism consisting of vendor and buyer, where the vendor and buyer are two distinct independent logistic organizations.　We investigate how the coordination mechanisms as well as　sharing the information play an important role in decision making to increase the system performance and individual profitability of the supply chain. In order to reach the objective, we have formulated different types of coordinated models. Firstly, this study proposed a model that deals with a vendor-buyer multi-product, multi-facility and multi-customer location selection problem which subsume a set of manufacturer with limited production capacities situated within a geographical area. A Mixed Integer Linear Fractional Programming （MILFP） model has been formulated which maximize the ratio of return on investment of the distribution network. Intended for comparison the model, a Mixed Integer Program （MIP） is also formulated. The performance of the model is estimated by a numerical example. In addition, product distribution and allocation of different customers along with the sensitivity of the key parameters are analyzed.

Further, this research deals with an enterprise comprises of vendor-buyer and facility selection problem. The coordinated mechanism among the members of supply chain has been proposed to achieve the optimal solution as well as the optimal location for the warehouse. Further, considering a price-sensitive linear demand function with single vendor-buyer and multiple products-consumers, buyer’s MIP model, vendor’s Integer Problem （IP） model and coordinated MIP model have been formulated.　In order to investigate the functioning of the model a numerical example has been resolved by deploying Branch and bound algorithm. The model determines the optimum products distribution, allocation and facility location set. Results show that by coordination, the individual profit over and above joint profit could be increased and consumers purchasing price could be decreased.

Furthermore, the proposed investigation deals with a coordinated supply chain involving a single vendor and buyer. Further, instead of a price sensitive linear or deterministic demand function, a price-sensitive non-linear demand function is introduced. The work develops vendor’s optimization and integration model that brings together the four functional categories such as location, production, inventory and transportation. To facilitate the inventory cost, penalty cost and transportation cost, it is assumed that production and shipping functions of the vendor are continuously harmonized and occurred at the same rate. In this integrated supply chain, the Buyer’s Linear Program （LP）, vendor’s IP and coordinated MIP models have been formulated. Numerical example is presented which includes the sensitivity of the key parameters to illustrate the achievement of the models. The solution procedures demonstrate that the individual profit as well as joint profit could be increased by a coordination mechanism even though the demand function is non-linear. In addition, the results illustrate that buyer’s selling price as well as consumer’s purchasing price could be decreased which may increase the demand of the end market.

Finally, this exploration deals with the implementation of coordination and supply chain optimization in real world case. In this part of the research, a simulated coordinated supply chain containing manufacturer, whole seller, retailer and consumer are investigated. The proposed model estimates the production and consumption of several commodities for each firm. In order to reach the optimal production and consumption the economics soft factors and hard factors of different firms are considered. The parameter of the soft and hard factors on the production and consumption for each firm are estimated by linear regression analysis. The buyers firms have some coordination with the vendor that influences the buyers firm to purchase some commodity from the coordinated vendor firm. As a result, commodity flow and distribution occur between vendor and buyer. The coordination that makes a commodity flow between vendor and buyer is determined by the logistic regression. The role of the key parameters on decision of purchasing a commodity by coordination is estimated. The empirical results of the model that is statically good enough has engaged to analyze coordination mechanism on the commodity consumption, generation and distribution in the Tokyo metropolitan area.

The results of these models illustrate that after coordination, vendor-buyer joint profit as well as individual profits could be increased without any additional investment. At the same way, coordination among the member of an enterprise could be reduced the consumer purchasing price as well as buyer selling price. In addition, after coordination the demand of the customer might be greater than before because by coordination the distribution become much consistent. The case study demonstrates that optimum production-consumption and distribution of different commodity depend on the coordination of hard and soft factors of the Buyer firm, Vendor firm and location of the firm.

本論文は，「Supply Chain Optimization and Coordination in Vendor Buyer Systems （供給者と需要者の調整を考慮したサプライチェーンの最適化） 」と題し，以下の8章より構成されている．
第1章「Introduction」では，サプライチェーン・マネジメントにおおけるコーディネーションモデルの重要性について述べ，本研究の必要性と適用範囲を記述している．
章2章「Literature Review」では，サプライチェーン・マネジメントに関する一般的な背景や，供給者と需要者のコーディネーションを考慮したサプライチェーンの最適化問題に関連する既存研究を紹介している．
第3章「Conceptual Framework」では、供給者と需要者のコーディネーションモデルの概略を説明するとともに，現実世界における商品の生産量と消費量の調整のメカニズムを説明している．
第4章「Vendor-Buyer Coordination and Supply Chain Optimization with Deterministic Demand Function」では、単一の供給者が，複数の品目を，複数の需要者の最適施設配置問題の定式化とモデルの挙動の分析を行っている．
第5章「Vendor-Buyer Coordination and Supply Chain Optimization with Linear Demand Function」では、線形需要関数を用いた，サプライチェーン最適化問題の定式化とモデルの挙動の分析を行っている．
第6章「Vendor-Buyer Coordination, Integration and Supply Chain Optimization with Non-linear Demand Function」では、非線形需要関数を用い，サプライチェーン最適化問題の定式化とモデルの挙動の分析を行っている．
第7章「Implementation of Coordination and Supply Chain Optimization in Real World Case」では，ハードとソフトの要因を考慮した生産/消費量推定モデルを構築し，実データを用いてモデルを同定した。
第8章「Conclusions and Recommendations」では、各章で示したモデルの特徴をまとめ，今後の課題をまとめている．

　以上のように，本論文は，供給者と需要者の調整を考慮したサプライチェーンの最適化モデルを構築することにより，新しい知見を与えている．よって，本論文は工学上及び工業上貢献するところが大きく，博士（工学）の学位論文として十分な価値を有するものと認める。