Optimizing supply chain network for perishable products using improved bacteria foraging algorithm

In a supply chain environment, time delay has a significant impact on the success of perishable products. A major concern is therefore aimed at development of a holistic optimized approach in a supply chain environment for perishable products. Thus, integration of production, inventory and, distribution of perishable products in a supply chain environment are the challenging tasks for practitioners and researchers. In general, the standard optimal supply chain model cannot work for perishable products. There is therefore, a need for a holistic model that focuses on the consolidation of the processes. Shorter product shelf-life, temperature control, requirement of strict tractability, large number of product variants, and a large volume of goods handled are the major challenges in a supply chain environment for perishable products. The present work focuses on the development of a holistic model which uses improved bacteria forging algorithm (IBFA) for solving the formulated model. We have proposed and analyzed some general properties of the model and, finally applied it to a three-stage supply chain problem using an IBFA. Two case studies have been considered for support and demonstration of the integrated perishable supply chain network problem. Results obtained from IBFA reveal that the proposed model is more useful for decision makers while considering optimal supply chain network for perishable products. Finally, validation of results has been carried out using bacteria forging algorithm (BFA). The computational performance of the proposed algorithm proves that IBFA is instrumental in effectively handling the proposed approach.     

Systems dynamics modelling of a manufacturing supply chain system

Supply chains are multifaceted structures focusing on the integration of all the factors involved in the overall process of production and distribution of end products to the customers. Growing interest in supply chain systems has highlighted the need to adopt appropriate approaches that can ensure the efficient management of their complexity, enormity and broadness of scope. With the main aim of supply chain management being to optimise the performance of supply chains, attention is mainly drawn to the development of modelling frameworks that can be utilised to analyse and comprehend the dynamic behaviour of supply chains. While there have been only a few supply chain modelling attempts reported in the literature, this paper proposes a modelling framework that is used to simulate the operation of a supply chain network of moderate complexity. The proposed model comprises four echelons and is build around a central medium-sized manufacturing company operating as a typical Make-to-Order (MTO) system. The developed model was built using a systems dynamics (SD) approach. The operations performed within a supply chain are a function of a great number of key variables which often seem to have strong interrelationships. The ability of understanding the network as a whole, analysing the interactions between the various components of the integrated system and eventually supplying feedback without de-composing it make systems dynamics an ideal methodology for modelling supply chain networks. The objective of the paper is to model the operation of the supply chain network under study and obtain a true reflection of its behaviour. The modelling framework is also used to study the performance of the system under the initial conditions considered and compare it with that obtained by running the system under eight different scenarios concerning commonly addressed real-life operational conditions. The modelling effort has focused on measuring the supply chain system performance in terms of key metrics such as inventory, WIP levels, backlogged orders and customer satisfaction at all four echelons. The study concludes with the analysis of the obtained results and the conclusions drawn from contrasting the system’s performance under each investigated scenario to that of the benchmark model.     

Assessing the value of information sharing and its impact on the performance of the various partners in supply chains

With major developments in information and communication technologies, real-time information sharing becomes a significant challenge and has a considerable impact on the overall performance of supply chains. Here, we study the influence of information sharing for a monoproduct serial supply chain consisting of a supplier, warehouse, retailer and customers in the context of a decentralized decision. The objectives of this study are twofold: (1) to estimate the gains from sharing different types of information on each elementary cost and for each partner of the supply chain in detail and (2) to determine the cumulative impact of simultaneously sharing different types of information.A mathematical model is developed to assess the value of information sharing in terms of logistic costs and for different combinations related to the sharing or non-sharing of three types of upstream and downstream information: the customer demand and the supplier-warehouse and warehouse-retailer lead times. A perturbation is also injected to consider the intended or unintended distortion in the communicated information.Our study clearly showed that the gains are not cumulative when we simultaneously share different types of information. The results also highlighted the necessity to establish incentive cooperation mechanisms between the different links in the supply chain in many scenarios where the gains are not balanced. A distortion in the communicated information can also have a significant effect on the gains from sharing.     

A control model for object virtualization in supply chain management

Due to the emergence of the Internet of Things, supply chain control can increasingly be based on virtual objects instead of on the direct observation of physical objects. Object virtualization allows the decoupling of control activities from the handling and observing of physical products and resources. Moreover, virtual objects can be enriched with information that goes beyond human observation. This will allow for more advanced control capabilities, e.g. concerning tracking and tracing, quality monitoring and supply chain (re)planning. This paper proposes a control model for object virtualization in supply chain management, which is based on a multiple case study in the Dutch floriculture. It includes a typology of distinct mechanisms for object virtualization, which discerns reference objects and future projections next to the representation of real physical objects. The control model helps to define feasible redesign options for the virtualization of supply chain control. It is also of value as a basis to define the requirements for information systems that enable these redesign options.     

A model measurement system for collaborative supply chain partners

The purpose of this paper is to understand business performance in the context of an electronic component company. This paper developed a system dynamics model that describes supply chain process structure and examines scenarios, as well. Thus, this study adopted the signal-to-noise (SN) ratio defined by the Taguchi method to evaluate the robustness of a specific supply chain behavior. Resulting in poor inventory cost performance with uncertainty demand, this paper shows how the factor delivery time and lead time of an order can improve performance. Finally, this paper serves as a guideline for decisions that require different inventory strategies.     

Supply chain redesign for resilience using simulation

Supply chains are facing numerous changes that are contributing to increasing their complexity and vulnerability to disturbances, therefore, to survive, supply chains must be resilient. The paper presents a supply chain simulation study for a real case concerned with the Portuguese automotive supply chain. The subset automotive supply chain involved in the case study is a three-echelon supply chain, composed by one automaker, two 1st-tier suppliers, two 2nd-tier suppliers, and one outsource entity. The purpose of the study is to evaluate alternative supply chain scenarios for improving supply chain resilience to a disturbance and understanding how mitigation strategies affect each supply chain entity performance. Two strategies widely used to mitigate disturbance negative effects on supply chains were considered and six scenarios were designed. The scenarios differ in terms of presence or absence of a disturbance in one hand and presence or absence of a mitigation strategy in other hand. To evaluate the scenarios designed, two performance measures were defined per supply chain entity, Lead Time Ratio and Total Cost.     

A hierarchical model of the impact of RFID practices on retail supply chain performance

The primary purpose of this study was to evaluate the impact of radio frequency identification (RFID) practices on supply chain performance. We examined eight variables of RFID applications grouped in two categories: location (supplier’s warehouse, retailer’s central warehouse, retailer’s local warehouse, retailer’s owned stores) and utilisation (standards, transportation, pallet level, specialised software). Given the inherent difficulty in assessing supply chain performance and the widespread use of different performance models, such as the SCOR and balanced scorecard, we developed a list of performance indicators. Factor analysis produced 7 supply chain performance factors: supplier, inventory, distribution, ordering, plan, sales, and forecasting.Empirical data were collected via an online survey administered to 300 retail companies. 130 usable questionnaires were returned, for a 43.3% response rate. To the best of our knowledge, this is the first study to provide an analytical model that places supply chain performance indicators as dependent variables in a hierarchical regression equation with RFID variables as independent variables. Results found that the implementation of RFID practices significantly affect the supply chain performance in the following areas: supplier, inventory, distribution, plan, sales, and forecasting. RFID can improve the performance of distribution systems, including products dispatched and inventory in transit by 33.8% and stock availability by 45.6%. This study contributes to both the RFID and the supply chain performance literatures. Limitations and suggestions for further research are also discussed.     

物流单元质量安全信息追溯预警模型研究

针对物流单元在生产供应链中出现的产品质量安全问题,分析可追溯体系中的质量监控需求,提出了一种用于供应链可追溯系统的预警模型,对整个供应链的检测数据进行汇总分析,预警可能导致物流单元质量问题的原因并进行诊断。针对供应链中四种常见的数据异常,提出了基于径向基函数神经网络、统计学分析的分析算法。实例分析和结果表明,该预警模型能够有效地区分异常数据的类型,实时地对追溯系统的检测数据进行监控及预警。     

A new efficient encoding/decoding procedure for the design of a supply chain network with genetic algorithms

Supply chain network (SCN) design is a strategic issue which aims at selecting the best combination of a set of facilities to achieve an efficient and effective management of the supply chain. This paper presents an innovative encoding–decoding procedure embedded within a genetic algorithm (GA) to minimize the total logistic cost resulting from the transportation of goods and the location and opening of the facilities in a single product three-stage supply chain network. The new procedure allows a proper demand allocation procedure to be run which avoids the decoding of unfeasible distribution flows at the stage of the supply chain transporting products from plants to distribution centers. A numerical study on a benchmark of problems demonstrates the statistical outperformance of the proposed approach vs. others currently available in literature in terms of total supply chain logistic cost saving and reduction of the required computation burden to achieve an optimal design.     

Guidelines for Collaborative Supply Chain System Design and Operation

Over the past decade, firms have adopted supply chain management as a critical element of their corporate strategies. Despite these efforts, it is our observation that many firms do not realize the anticipated benefits of constructing collaborative operating relationships with supply chain partners. Our purpose in this paper is to establish a set of guiding principles for the effective design and execution of supply chain systems. These principles suggest why, what, and how collaborative relationships should be constructed.While constructing and operating a competitive supply chain is the primary objective of supply chain management, we have observed several impediments to achieving this goal. First, demand uncertainty is so substantial in most supply chain environments that if it is not adequately addressed, it can severely degrade the anticipated performance of the supply chain as measured in terms of unit cost, speed, quality, and responsiveness to changing conditions. Second, supply chains with poor physical characteristics that operate with long and variable response times cannot take full advantage of collaborative relationships due to their inability to respond to changes in the environment. Third, firms with poor information infrastructures lack the capabilities necessary to acquire, store, manipulate, and transmit data effectively and quickly. Fourth, business processes are often not designed properly, both intra- and inter-organizationally, to adapt to evolving supply chain conditions. Finally, decision support systems and operating policies that guide day-to-day operating decisions may not be adequately designed to contend with supply chain uncertainty.We also suggest that the strategic and tactical modeling paradigms employed in supply chain decision support systems are inadequate in many operational environments because of the manner in which uncertainty is treated. Furthermore, collaborative relationships that focus on reducing the uncertainty in operating environments by employing improved information systems and business processes will result in more efficient allocation of key resources, faster response times to market forces, and more reliable supply chain performance; however, these collaborative arrangements by themselves cannot compensate for fundamentally flawed and operationally ineffective manufacturing and distribution environments.     

考虑损失厌恶和锚定心理的供应链订货与协调

为更合理地实现供应链协调的整体最优绩效,以具有损失厌恶和锚定心理的零售商和风险中性的供应商组成的两级供应链为研究对象,探讨回购契约下的供应链订货及协调情况。建立集中和分散决策下考虑零售商损失厌恶和锚定心理的回购契约协调模型,分析了零售商最优订货量与批发价格、回购价格之间的关系,以及各契约参数对回购价格和各节点利润的影响,并给出了供应链实现协调需要达成的条件。结果表明,当零售商订购的产品为高利润产品时,能够实现供应链整体最优绩效,达到供应链协调,且利润在供应链双方之间的分配随着批发和回购价格的提升而向供应商倾斜,但零售商损失厌恶和锚定心理的加深会使得供应商提升回购价格,使整体供应链的利润下降,成本费用增加。     

Post-seismic supply chain risk management: A system dynamics disruption analysis approach for inventory and logistics planning

Post-seismic inventory and logistics planning under incomplete and fuzzy information is an important yet understudied area in supply chain risk management. The goal of this paper is to propose a system dynamics model to analyze the behaviors of disrupted disaster relief supply chain by simulating the uncertainties associated with predicting post-seismic road network and delayed information. The simulation results indicate: (1) information delay has different influences over the relief head-quarter (the upstream) and the disaster-affected areas (the downstream); and (2) the change of road conditions and shipment schedules have impact on the on-time transportation rate in supply chain management. Furthermore, this paper defined and tested supplies' replenishment solutions combined with three inventory planning strategies and four forecasting methods under different lead time uncertainties. The results show that: (1) a strategy that considers information from both the post-seismic management center and the affected areas can provide a better logistic plan than an one takes information from one side; (2) the smooth-the-trend forecasting method is suitable for inventory and logistic planning when the post-seismic situations are volatile, while the quick-response forecasting method has good performance in stable environments. In addition, this paper proposes decision tree to help decision makers choose the appropriate stocking strategies.     

基于期权的供应链数量柔性契约决策模型

针对单个制造商和单个销售商组成的多周期单产品两级供应链协调问题, 建立了期权与数量柔性契约相结合的决策模型; 需求的不确定性通过有限的情境描述, 采用逐步对冲算法对基于情境的随机规划模型进行求解, 给出了销售商最优的期权购买量和初始订货量以及制造商最优的原材料采购量和产品生产量; 最后通过数值仿真实验验证了所提出模型的有效性.

     

An innovative supply chain performance measurement system incorporating Research and Development (R&D) and marketing policy

Various performance measurement techniques have been developed and applied in their respective fields, but the existing performance measurement methods have failed to provide significant assistance in the context of marketing strategies and innovation levels of a firm. In this paper, we have considered an important aspect of marketing policy involving examining the decision of a firm to distribute products and services to its consumer. The model developed in this paper is an extension to the Bass diffusion model which is generalized to incorporate the effects of marketing policy of the firm. In order to examine our model, computer simulation is conducted in order to measure the effect of innovation level and distribution of products and services on the change in the sales of a firm from its previous products and supply chain system. The performance measurement was developed by examining firm’s level of innovation achieved by their Research and Development (R&D) performances, and sales of the products and services.     

供应链流程绩效评估模型及其系统实现

提出一种基于流程分解的供应链流程绩效评估模型。该模型在流程分解的基础上,从质量、时间、成本、协同性和资产利用5个维度出发,对供应链业务流程进行绩效评估。基于该模型设计开发供应链绩效评估系统,通过某航运公司的集装箱航运供应链流程实例验证该模型的可行性。     

Impact of the integration of tactical supply chain planning determinants on performance

In fulfilling customers’ orders, one of the goals of tactical supply chain planning is to satisfy the customers in terms of delivery efficiency, delivery quantity accuracy and on-time delivery. These performance objectives can be impacted by the way firms plan each of the three phases of the supply chain: procurement, production and distribution. Though the link between each of these phases and supply chain performance has been studied in extant literature, very few authors have considered all three phases at the same time. By adopting an integrated approach, this paper therefore aims to study the manner in which, taken together in one model, the planning determinants of the different phases impact on supply chain performance. It is important for managers to understand, from a holistic and integrated perspective, how a given combination of the planning determinants of the supply chain functions impacts positively or negatively on the performance of the supply chain. To carry out this study, this paper starts by proposing an integrated framework that is based on the SCOR model and the customer order decoupling point (CODP), followed by a five-step methodology for tactical supply chain planning. Then, using an analytical model and simulations, and based on a numerical example, it shows how the proposed methodology can be applied in a given decision-making situation. Our results enabled to identify the worst and the best combinations of planning determinants.     

A closed-loop logistic model with a spanning-tree based genetic algorithm

Due to the problem of global warming, the green supply chain management, in particular, closed-loop logistics, has drawn the attention of researchers. Although there were logistics models that were examined in the literatures, most of them were case based and not in a closed-loop. Therefore, they lacked generality and could not serve the purposes of recycling, reuse and recovery required in a green supply chain. In this study, the integration of forward and reverse logistics was investigated, and a generalized closed-loop model for the logistics planning was proposed by formulating a cyclic logistics network problem into an integer linear programming model. Moreover, the decisions for selecting the places of manufactories, distribution centers, and dismantlers with the respective operation units were supported with the minimum cost. A revised spanning-tree based genetic algorithm was also developed by using determinant encoding representation for solving this NP model. Numerical experiments were presented, and the results showed that the proposed model and algorithms were able to support the logistic decisions in a closed-loop supply chain efficiently and accurately.

Statement of scope and purposes

This study concerns with operations of 3R in the green supply chain logistics and the location selection optimization. Based on ‘cradle to cradle’ principle of a green product, a “closed-loop” structure of a network was proposed in order to integrate the environmental issues into a traditional logistic system. Due to NP-hard nature of the model, a Genetic Algorithm, which is based on spanning tree structure was developed. Test problems from the small size for accuracy to the large scale for efficiency have been demonstrated with comparison. The promising results have shown the applicability of the proposed model with the solution procedure.     

A mixed integer nonlinear programming model and heuristic solutions for location,inventory and pricing decisions in a closed loop supply chain

We analyze a network design problem for a closed-loop supply chain that integrates the collection of the used products with the distribution of the new products. We present a mixed integer nonlinear facility location-inventory-pricing model to decide on the optimal locations of the facilities, inventory amounts, prices for new products and incentive values for the collection of right amount of used products in order to maximize the total supply chain profit. We develop heuristics for the solution of this model and analyze the effectiveness of these heuristics and the effects of the parameters on this system through numerical experiments.     

基于区块链的游戏软件产品版权保护研究

目前关于区块链应用场景和理念设计的研究较多,但基于供应链协调视角揭示区块链应用的影响仍较缺乏。以游戏软件产品供应链为例,探讨了区块链场景下在线渠道消费者购买效用折扣系数和盗版用户效用折扣系数对均衡价格、均衡利润的影响。结果表明,供应商的利润提高幅度最大,提高量弥补了零售商的损失量,因此供应链整体利润得到优化。此外,通过构建并求解区块链场景下某类仿制软件供应链均衡价格和均衡利润模型,发现仿制软件供应商的价格优势不再明显,甚至消失。最后,考虑到零售商在区块链场景下均衡利润减少的事实,针对性地提出各成员基于供应链协调分配利润角度的相关对策建议。     

Allocation of external returns of different quality grades to multiple stages of a closed loop supply chain

A single period multistage closed loop supply chain (CLSC) is presented here considering simultaneous manufacturing of new products and remanufacturing of customer returned used products. The quantity of used products in reverse supply chain considered in the model is a fraction of the new products manufactured in the forward supply chain. Used products of known quantity are pulled from end customers as per quality grades. Products are assumed to be mechanical in nature and remanufacturer has to pay different acquisition prices for different quality grades of return. The groups of graded products based on the acquisition prices are thus sorted and sent to stages of CLSC earmarked for them as per demand for repairing/recycling of raw materials. After repairing/refurbishing and recycling at each stage of reverse supply chain the used parts/products become part of forward supply chain. In this paper, a nonlinear maximizing profitability function for CLSC has been formulated for the system with a price dependent demand for n-stages. The decision variables are selling price of product and percentage return of graded used products entering into different stages. A numerical example for a three stage model illustrates the method followed by managerial insight.