An analysis of contract form for supply chains with quality improvement

This study examines different contract forms for the supply chain with quality improvement decision and retailer price decision. We consider three types of quality improvement: cost consuming, cost identical, and cost saving, which correspond to the cases in which quality improvement leads to an increment, no change, and a decrease in production cost, respectively. We compare the performance of two types of quality contracts: (1) pay‐before‐performance contract, under which the supplier receives monetary support from the buyer before exerting quality improvement effort; and (2) pay‐after‐performance contract, under which the supplier receives monetary compensation based on the outcome of effort. We find that the performance of each contract depends on the types of quality improvement. Further, the pay‐after‐performance contract leads to close‐to‐perfect contract efficiency and dominates the pay‐before‐performance contract from the supplier's perspective in most cases. However, this result does not apply in two extended cases: when there are multiple competing suppliers, the pay‐before‐performance contract can dominate the pay‐after‐performance contract if quality improvement is cost consuming; and when the buyer can exert sales effort, neither contract can achieve close‐to‐perfect efficiency in most cases.     

On the information modeling for the electronic operation of supply chains: A maritime case study

Nowadays, the manufacturing industry is adopting modern information technologies in order to optimize their business process and to achieve integration with supply chain partners that are geographically dispersed, by expanding the physical limits of their business globally. The growth of the World Wide Web and the advantages of the software technologies arising from it render this goal possible. This paper discusses how modern information technology, particularly the ISO 10303—STEP and eXtensible Markup Language—XML, can be utilized jointly to support the communication of different partners. An approach to support enterprise operation through efficient data exchanges, by adopting modern data modeling techniques for integration among partners worldwide and using the web as a communication layer, is described. The paper deals particularly with the ship repair industry as a case study of these problems and suggests a feasible solution.     

Modelling the dynamics of supply chains

A summary of the important issues arising in supply chain research is presented. A review of the various mathematical methods used to model and analyse supply chains is then undertaken. They are categorized as: continuous time differential equation models, discrete time difference equation models, discrete event simulation models and operational research techniques. Each method is then appraised from a system dynamics perspective. To conclude, a judgement is made on whether the merits of operational research techniques justify their predominance in industry over the other methods presented here.     

Product quality prediction method in small sample data environment

The low degree of enterprise digitization and the existence of personalized customization and small batch production manufacturing modes lead to the characteristics of small samples and high dimensions of data collected by manufacturing enterprises. The product quality prediction method based on big data is prone to overfitting in the small sample and high dimensional data environment, and the model generalization performance is poor. In order to solve the above problems, this paper conducts research in two aspects of data augmentation and model optimization respectively. At the data augmentation level, a data generation model RVAE-CGAN is proposed, RVAE constrains the value space of GAN and eliminates the influence of outliers in the original data on the quality of generated samples. Using DBSCAN to cluster raw data to generate conditional vectors for guiding sample generation, and finally obtain high-quality generated samples. At the model optimization level, a product quality prediction model PPO-SVR is proposed. The PPO method is used to optimize the hyperparameters of the SVR model and improve the prediction effect of the model. RVAE-CGAN and PPO-SVR models are combined, and RVAE-CGAN is used to expand the number of samples to train PPO-SVR. The experimental results show that the product quality prediction model constructed based on RVAE-CGAN and PPO-SVR outperforms the BP neural network prediction model trained on mixed data. Therefore, the combination of data augmentation and model optimization proposed in this paper can significantly improve the prediction effect of the product quality prediction model in the small sample data environment.     

A framework for evaluation of coordination by contracts: A case of two-level supply chains

A supply chain consists of disparate but inter-dependent members who are dependent on each other to manage various resources (such as inventory, money and information). The conflicting objectives and lack of coordination between these members may often cause uncertainties in supply and demand. Coordination may help in managing inter-dependencies and reducing uncertainties. Typically, a mechanism is required to streamline the whole supply chain and motivate all the members to be a part of the entire supply chain for sharing risks and rewards through supply chain contracts.The objective of this paper is to explore the applicability and benefits of the contracts. A two-phase framework is proposed consisting of a decision support tool and a graph-theoretic model for evaluation of coordination in a two-level supply chain. In Phase I, an analytical model is proposed based on the classical newsboy problem. Various contract mechanisms have been explored through a decision support tool based on the simulation. The effectiveness of these contracts is evaluated through a graph-theoretic model in Phase II. It is expected that by designing the contracts as per the requirements of the supply chain members as well as the whole supply chain, supply chain performance may be improved.     

SOA in reconfigurable supply chains: A research roadmap

Originally coming from the business world, service-oriented architecture (SOA) paradigm is expanding its range of application into several different environments. Industrial automation is increasingly interested on adopting it as a unifying approach with several advantages over traditional automation. In particular, the paradigm is well indicated to support agile and reconfigurable supply chains due to its dynamic nature. In this domain, the main goals are short time-to-market, fast application (re)configurability, more intelligent devices with lifecycle support, technology openness, seamless IT integration, etc. The current research challenges associated to the application of SOA into reconfigurable supply chains are enumerated and detailed with the aim of providing a roadmap into a major adoption of SOA to support agile reconfigurable supply chains.     

NAFTA supply chains: facilities location and logistics

North American Free Trade Agreement (NAFTA), the free‐trade agreement between Canada, Mexico and the United States, has caused North American companies to consider inclusion of Mexico in their supply chain. The lower Mexican wages may offset the additional transportation costs; capital‐intensive operations are preferably still done in the United States or Canada. With a consumer base focused in the United States, can an organisation leverage the benefits of NAFTA to their individual advantage? This paper aims to show how, through a real‐world example, overall supply chain costs (total system costs of inventory, transportation and facilities) can be minimised under those circumstances. We formulate and solve a mixed‐integer programming model to find the optimal supply chain for Tectrol Inc., a manufacturer of power supplies. In the first case, components produced in Canada undergo final assembly in the United States, followed by distribution there. The second case is a ‘NAFTA’ supply chain: the Canadian components are converted to sub‐assemblies in Mexico, processed in finishing plants across the US border, then shipped through distribution centres to the final customer. Model solutions indicate in each instance where to locate finishing plants and distribution centres, and how many of each there should be. Results provide Tectrol (hence other manufacturers) some general guidelines on distribution and supply chain decisions in the NAFTA context.     

Electronic supply chains: Status & perspective

The area of e-commerce based supply chains (or e-supply chains) has received significant attention in the last two decades. Despite the high level of activity, the most recent reviews on this topic date back to the beginning of this century. In this paper, we analyzed the state of e-supply chain research published during January 2000–January 2015 AD, covering 165 articles from 47 ISI indexed journals. The analysis is performed using a five-dimensional framework comprising Topic-of-Study, Unit-of-Analysis, Research Perspective, Industry Type, and Research Method. Within these dimensions, Topic-of-Study plays a pivotal role, whereas the other four dimensions are analyzed around its sub-classification scheme. Our main objective is to establish a broader interdisciplinary understanding of the e-supply chain research domain, and to identify trends and gaps in contemporary e-supply chain theory and practice. The findings indicate that problems are addressed from different perspectives with varying levels of interest from researchers belonging to several academic disciplines including business, economics, engineering and social sciences. Our analysis also identified two distinct periods (2000–2006 and 2007 onwards) with different foci of research attention. The problems that received significant attention in the earlier period include innovation, adoption and barriers, and supply chain integration; while in the latter period, the focus seemed to have shifted towards supply chain integration and collaboration issues. Problems that received minimum interest across the two periods include customer relationship, economic and environmental impact.     

Product backlog rating: a case study on measuring test quality in scrum

Agile software development methodologies focus on software projects which are behind schedule or highly likely to have a problematic development phase. In the last decade, Agile methods have transformed from cult techniques to mainstream methodologies. Scrum, an Agile software development method, has been widely adopted due to its adaptive nature. This paper presents a metric that measures the quality of the testing process in a Scrum process. As product quality and process quality correlate, improved test quality can ensure high-quality products. Also, gaining experience from 8 years of successful Scrum implementation at SoftwarePeople, we describe the Scrum process emphasizing the testing process. We propose a metric Product Backlog Rating (PBR) to assess the testing process in Scrum. PBR considers the complexity of the features to be developed in an iteration of Scrum, assesses test ratings and offers a numerical score of the testing process. This metric is able to provide a comprehensive overview of the testing process over the development cycle of a product. We present a case study which shows how the metric is used at SoftwarePeople. The case study explains some features that have been developed in a Sprint in terms of feature complexity and potential test assessment difficulties and shows how PBR is calculated during the Sprint. We propose a test process assessment metric that provides insights into the Scrum testing process. However, the metric needs further evaluation considering associated resources (e.g., quality assurance engineers, the length of the Scrum cycle).     

The physics of e-commerce supply chains

The Internet is rapidly improving our ability to support information flows across global supply chains. However, the business impact of these IT investments depends not just on the information flows supported by such systems, but also on other non-information related characteristics of the supply chain. It is the complex interplay among these characteristics that results in business performance, or lack thereof. In order to better understand the business impact of IT investments in the supply chain, we are motivated to examine the ‘physics’ of supply chain structures. By physics, we mean the performance patterns inherent in its informational and physical characteristics. Using the systems dynamics methodology, we model basic information and physical characteristics of supply chains and examine their impact on some common measures of performance. Experiments with the models suggest that, in addition to information delays, physical delays also have a major impact on the stability of supply chains, as well as on operating cost. Moreover, the tradeoff between chain stability and responsiveness appears to be nonlinear, suggesting that a small compromise in responsiveness may yield larger gains in stability. Multi-tier chains appear to be less ‘stiff’ in responding to demand fluctuations, implying that their information systems must be specifically designed to overcome this structural tendency. These results have managerial implications in terms of designing the information and physical structure of a supply chain as well as for its operation.     

Transparency in complex dynamic food supply chains

Food supply chains are increasingly complex and dynamic due to (i) increasing product proliferation to serve ever diversifying and globalising markets as a form of mass customisation with resulting global flows of raw materials, ingredients and products, and (ii) the need to satisfy changing and variable consumer and governmental demands with respect to food safety, animal welfare, and environmental impact. Transparency in the food supply chain is essential to guarantee food quality and provenance to all users of food and food products. Intensified information exchange and integrated information systems involving all chain actors are needed to achieve transparency with respect to a multitude of food properties.In this paper, specific challenges of food supply chains are highlighted. Major elements are addressed that support transparency to consumers, the government and food companies, which are considered the claimants of transparency. Elements considered to be enablers of transparency are governance mechanisms, quality and safety standards and information exchange. The paper specifies these transparency claimants and enablers for food supply chains and identifies major information system functions and information technology applications needed to comply with transparency demands. It thereby provides a framework for transparency analysis in food supply chains.     

A typology of the situations of cooperation in supply chains

Pushed by globalization and its consequent increased competition, supply chain managers have understood the importance of information sharing, joint decision-making and cooperation across supply chains. Therefore, how to synchronize local activities through global processes and how to establish a collaborative supply chain relationship are actual difficulties that supply chain members have to address. In this context, this paper suggests a model of the situations of cooperation in supply chains for coping with real industrial situations, based on the analysis of the limitations of previous models. It is shown how the suggested model may allow to identify dysfunctions in the cooperation process, especially when both large and small companies are involved, and can also be used to describe and monitor the possible evolution of the cooperation process. Finally, the model may help to specify the way information should be efficiently processed all along a supply chain, depending on the situation of cooperation.     

Reliability of supply chains in a random environment

A supply chain is considered that operates in a random environment.The last is described by continuous-time finite irreducible Markov chain. Each state of the environment (the Markov chain) has its own probability of fatal failure as a result of the breakdown of the supply. There are algorithms for calculating the reliability of the chain (a probability of a successful supply) and the distribution function of the successful performance time presented in this paper. The numerical example illustrates the suggested approach.     

The price of anarchy in closed-loop supply chains

This paper measures the worst-case efficiency of price-only contracts in closed-loop supply chains (CLSCs) with the price of anarchy (PoA). We model a single-period Stackelberg game in which a manufacturer sells new products to a retailer and collects used products with exogenous retail price and collection price via three alternative reverse channels: (a) the manufacturer collects directly from customers, (b) the retailer collects for the manufacturer, and (c) a third party is awarded a collection subcontract from the manufacturer. We carry out a comprehensive investigation under push–pull configurations to observe how reverse channel structures with different gaming sequences of CLSC members influence the worst-case performance when the demand distribution is over the set of increasing generalized failure rate distributions. From our PoA analysis, we find that the pull system does not always outperform the push system, especially when the retailer is the leader, in contrast to the results for forward supply chains. While the PoA of the push system is dramatically sensitive to the quality condition of used products, the pull system has a constant efficiency loss that is independent of the quality condition. Instead, the PoA of the pull system solely changes with the gaming sequence of the manufacturer. We also find that manufacturer's direct collection is a better reverse channel choice compared to retailer's collection. Additional managerial insights are summarized for discussion.     

An intelligent adaptive system for the optimal variable selections of R&D and quality supply chains

The cost of research & development (R&D) and quality management are always regarded as two major parts of total cost. The variable performance of R&D and quality design is an important index that will reflect the effectiveness of the cost reduction. This research has attempted to simultaneously vary all of the variables to achieve the global optimum for the optimal variable selections of R&D and quality design. Genetic algorithm (GA) can treat all of the variables for the global search. In this study, fuzzy refinement with orthogonal arrays was effective in improving the performance of the GA, and also showed the benefits of a good chromosome structure on the behavior of GA. It is also proposed the postponement design with temporal concept, to select the effective variables for the cost reduction of R&D and quality management design. The experimental results showed that tempo-postponement design will increase the flexibility and quick response for supply chain management. Hence, this approach can act as a useful guideline for researchers working on the optimization of the key variable selections for R&D and quality model design.