Tailored Supply Chain Decision Making Under Price-Sensitive Stochastic Demand and Delivery Uncertainty

In this paper, we study a serial two-echelon supply chain selling a procure-to-stock product in a price-sensitive market. Our analytical modelling framework incorporates optimal pricing and stocking decisions for both echelons in the presence of stochastic demand and random delivery times. We focus on understanding how these decisions for the chain are affected by its management paradigm (centralized or decentralized), and its business characteristics---price sensitivity, demand uncertainty, and delivery time variability. A novel combination of transformations enables us to analyze the framework and determine the unique optimal choices for centralized and wholesale price-based decentralized supply chains. More detailed investigation reveals that, in general, the business characteristics influence both the behavior and the optimal values of the decision variables, while the management paradigm primarily governs the optimal values. We illustrate the significance of these results in terms of how managers should tailor their decisions to align with their business requirements. Subsequently, comparison of the optimal profits between the channel partners and the management paradigms provides implications for decentralization strategy. A decentralized chain is most inefficient for moderately price-sensitive customers and uncertain environments, but is relatively more effective when dealing with mature products. We propose a contracting scheme that can improve the decentralized chain profit in reliable delivery time settings. The salient modelling insight of this paper is that ignoring the randomness of delivery time trivializes the interaction between pricing and stocking decisions. On the other hand, from a managerial viewpoint, we establish that optimal pricing policies provide the means to increase revenue and also act as strategic tools for tackling uncertainty.pricing, stochastic demand, random delivery times, multiechelon inventory, customized supply chains

A manufacturer-service provider model with remanufacturability and variable product life considerations

There has been a growing emphasis on remanufacturing as a profitable means to reduce wastage, conserve energy and costs. An alternate approach to obtain similar environmental and economic benefits is to increase the product life. We model and analyze the economic relationships among the level of remanufacturing, product life and economic consequences under the framework of a manufacturer/remanufacturer and a service provider who utilizes the manufacturer\u27s product to provide service to his/her customers. In our framework, the remanufacturability is defined as the fraction of used products that can be economically remanufactured, and it is assumed that the remanufacturability can be increased via fixed cost investment in product and process design technologies. We also assume that the product life which is defined to be the number of units of service that is provided from the product can be increased by utilizing higher quality components with corresponding higher variable cost. Under these assumptions, we formulate three distinct supply chain scenarios. Namely, a manufacturer driven supply chain, a centrally coordinated supply chain and a service provider driven supply chain. From the subsequent equilibrium and optimality analysis, we derive several interesting managerial insights. For example, there are several conditions under which a higher technology investment in remanufacturability leads to a shorter product life

Decentralized and centralized supply chains with trade credit option

The notion of a trade credit period is a common business practice, where a supplier allows a buyer a specified period to make a payment in full for a purchase made. The objective of this thesis is to explore the role of such a credit payment option in supply chain management. Towards this end, a two-echelon supply chain, consisting of a single supplier (e.g. manufacturer) and the cases of both a single and multiple buyers (e.g. retailers) is examined under decentralized (independent) and centralized (coordinated) decision making scenarios. The major emphasis of this research is limited to the case of a single product with price-sensitive deterministic, as well as stochastic market demand.The conditions under which a trade credit period should be offered and its appropriate length are determined from the supplier’s perspective under the decentralized case. Under the centralized decision scenario, the efficacy of a trade credit policy as a supply chain coordination mechanism is thoroughly analyzed and guidelines for pricing, production and delivery decisions are developed. The concepts developed in this study are illustrated via a number of numerical examples, in conjunction with thorough sensitivity analyses involving some selected problem parameters.The major contribution of this thesis is that we incorporate the pricing and inventory issues in supply chains with an endogenous credit payment period. This is the first study that examines the efficacy of trade credit option as a coordination mechanism. We propose a coordination mechanism that coordinates the supply chain, when a trade credit by itself is not sufficient to serve such a purpose, while preserving the benefits of a trade credit option. Also, this study is the first to examine the issues concerning trade credit under price sensitive stochastic demand. Another first for this work is the exploration of the implications of a trade credit policy in supply chains consisting of multiple competing retailers. The effects of the extent of competition and the market size on trade credit policy are evaluated. Our analyses lead to some important practical implications, to serve as managerial guidelines.Ph.D., Decision Sciences -- Drexel University, 201

Tedarik zinciri risklerinin işletme performansına etkisi : otomotiv yan sanayisinde bir uygulama

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Teknolojide meydana gelen gelişmeler mal ve hizmetlerin küresel alana yayılmasını sağlamış, pazarlarının giderek daha dinamik bir hal almasına sebep olmuştur. Sanayileşmenin 19. yüzyılda ortaya çıkması ve gün geçtikçe hızlı bir şekilde gelişmesi, üretim tekniklerinin çok hızlı değişip gelişmesine, toplumsal gereksinimlerin artmasına sebep olmuştur. Bu ise tedarik zinciri yönetiminin önemini artırmıştır. Diğer yandan tedarik zincirinde meydana gelen olumsuz bir olay (makina arızası, iş gücü yetersizliği, eksik malzeme, ürünün dağıtımındaki gecikmeler, vs.) tüm tedarik zincirinin performansını olumsuz yönde etkileyebilmektedir. Dolayısıyla, söz konusu bu olaylardan herhangi birisiyle karşılaşılması durumunda tedarik zincirinde risk sorununu ortaya çıkarmaktadır. Risk; genellikle istenmeyen, olumsuz bir durum olarak ifade edilmektedir. Fakat başarılı bir şekilde yönetildiğinde kârlılık arttırıcı bir araç olarak kullanılabilir. Bu kapsamda, tedarik zinciri performansını değerlendirirken tedarik zinciri risklerini belirlemek ve belirlenen risklerin sürekli izlenmesi önem kazanmaktadır. Bu çalışmanın dört amacı bulunmaktadır. Birinci amacı tedarik zincirinde risklerin nelerden oluştuğunu tespit etmektir. İkinci amacı algılanan risk düzeyleri ile bu risklerin işletme performansı üzerindeki etkisi arasında bir farkın olup olmadığını ortaya koymaktır. Üçüncü amacı, çevresel risk, ekonomik risk, güvenlik riski ve tedarikçi riskinin operasyonel risk üzerindeki etkisini belirlemektir. Çalışmanın son amacı ise risk azaltma stratejileri arasında yer alan süreç yönetimi ve tedarikçi ilişkilerinin operasyonel risk ve tedarikçi riski üzerindeki etkisini incelemektir. Bu çalışma için veriler Taşıt Araçları Yan Sanayiciler Derneği (TAYSAD) üyesi olan ve Bursa Nilüfer Organize Sanayi Bölgesinde (NOSAB) faaliyet gösteren 106 otomotiv yan sanayisi işletmesinden kolayda örnekleme yöntemi kullanılarak ve bu işletmelerin yöneticileriyle yüz yüze görüşülmek suretiyle toplanmıştır. Bulgular, tedarikçi riski (zamanında teslim ve istenilen miktarda teslim), operasyonel risk (sistemin durması, stok ve planlama riski), güvenlik riski (terörist faaliyet riski, yangın riski ve doğal afet riski) ve çevresel risklerin (finansal risk, talep riski) algılanan düzeyleri ile bunların işletme performansı üzerindeki etkileri arasında önemli düzeyde bir fark olduğunu ortaya koymuştur. Ayrıca çevresel risk, ekonomik risk ve tedarikçi riskinin operasyonel riskle pozitif yönde bir ilişkisi varken güvenlik riskinin operasyonel riskle bir ilişkisinin olmadığı belirlenmiştir. Çalışmanın bir diğer bulgusu ise süreç yönetimi ile iyi tedarikçi ilişkilerinin operasyonel ve tedarikçi riskini azalttığı tespit edilmiştir.Technological developments have provided the spread of goods and services to the global areas and gradually made the markets more dynamic. The emergence of the industrialization in 19th century and its rapid development has caused very quick changes and development in the production techniques and increase in social needs. This, on the other hand, has increased the importance of supply chain management. Within this framework, a negative event occurring in the supply chain (machine failure, insufficient labor force, delays in the distribution of the product etc.) may affect the performance of all supply chain. Therefore, the risk arises in the supply chain in case of facing such events. The risk is expressed generally as an undesirable, negative condition. However, if it is managed successfully, it may be used as a tool to increase profit. In this scope, when assessing the performance of the supply chain, the identification of the supply chain risks and tracking them continuously become crucial. There are four purposes of this study. The first is to put forth the composition of risks. The second is to determine if there is a significant difference between the level of perceived risk and the effects of these risks in the business performance. The third is to identify if there is an impact of environmental risk, economic risk, and security risk and supplier risks on the operational risk. And finally, the last objective is to determine whether there is an impact of process management and supplier relations, which are considered as risk-reducing strategies, on the operational and supplier risks. For this study, data was collected from 106 firms operating in the automotive sector which are members of Association of Automotive Parts and Components Manufacturers (TAYSAD) and which are operating in Bursa Nilüfer Organized Industrial Zone (NOSAB) by utilizing convenience sampling method and by having face-to-face interviews. Findings show that there is a significant difference between the perceived levels of supplier risk (delivery on time and delivery by the quantity requested), operational risk (system disruption, inventory, and planning risk), security risk (risk of terrorist activities, risk of fire and risk of act of god) and environmental risks (financial risk, demand risk) and their impact on the business performance. In addition, it is determined that economic risk, security risk, and supplier risk influences the operational risk. Another finding of this study is that good supplier relations and process management reduce the operational and supplier risk

Fuzzy Logic

Fuzzy Logic is becoming an essential method of solving problems in all domains. It gives tremendous impact on the design of autonomous intelligent systems. The purpose of this book is to introduce Hybrid Algorithms, Techniques, and Implementations of Fuzzy Logic. The book consists of thirteen chapters highlighting models and principles of fuzzy logic and issues on its techniques and implementations. The intended readers of this book are engineers, researchers, and graduate students interested in fuzzy logic systems