Supply chain uncertainty:a review and theoretical foundation for future research

Supply-chain uncertainty is an issue with which every practising manager wrestles, deriving from the increasing complexity of global supply networks. Taking a broad view of supply-chain uncertainty (incorporating supply-chain risk), this paper seeks to review the literature in this area and develop a theoretical foundation for future research. The literature review identifies a comprehensive list of 14 sources of uncertainty, including those that have received much research attention, such as the bullwhip effect, and those more recently described, such as parallel interaction. Approaches to managing these sources of uncertainty are classified into: 10 approaches that seek to reduce uncertainty at its source; and, 11 approaches that seek to cope with it, thereby minimising its impact on performance. Manufacturing strategy theory, including the concepts of alignment and contingency, is then used to develop a model of supply-chain uncertainty, which is populated using the literature review to show alignment between uncertainty sources and management strategies. Future research proposed includes more empirical research in order to further investigate: which uncertainties occur in particular industrial contexts; the impact of appropriate sources/management strategy alignment on performance; and the complex interplay between management strategies and multiple sources of uncertainty (positive or negative)

Wood-based construction project supplier selection under uncertain starting date

There is a growing interest in supply management systems in today's competitive business environment. Importance of implementing supply management systems especially in home construction industry is due to the fact that several risks arising from different sources can adversely affect the project financially or its timely completion. Some risks of construction projects are out of managers' control while other risks such as supply related ones can usually be controlled and directed by effective managerial tactics. In this paper, we address the supplier selection problem (SSP) in wood-based construction industry (housing projects) in the presence of project commencement uncertainties. Based on the suppliers' (vendors') reaction towards these uncertainties in the delivery time, we explore two cases: (a) supplier selection with buyer penalty for a delay (SSPD) where the price of product increases with the delay; (b) supplier selection with quantity reduction for a buyer delay (SSQRD). Three heuristic-based supplier selection approaches are proposed and tested on randomly generated data sets. The proposed approaches show promising result

An integrated approach to supply chain risk analysis

Despite the increasing attention that supply chain risk management is receiving by both researchers and practitioners, companies still lack a risk culture. Moreover, risk management approaches are either too general or require pieces of information not regularly recorded by organisations. This work develops a risk identification and analysis methodology that integrates widely adopted supply chain and risk management tools. In particular, process analysis is performed by means of the standard framework provided by the Supply Chain Operations Reference Model, the risk identification and analysis tasks are accomplished by applying the Risk Breakdown Structure and the Risk Breakdown Matrix, and the effects of risk occurrence on activities are assessed by indicators that are already measured by companies in order to monitor their performances. In such a way, the framework contributes to increase companies' awareness and communication about risk, which are essential components of the management of modern supply chains. A base case has been developed by applying the proposed approach to a hypothetical manufacturing supply chain. An in-depth validation will be carried out to improve the methodology and further demonstrate its benefits and limitations. Future research will extend the framework to include the understanding of the multiple effects of risky events on different processe

Supply chain network design under uncertainty and risk

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.We consider the research problem of quantitative support for decision making in supply chain network design (SCND). We first identify the requirements for a comprehensive SCND as (i) a methodology to select uncertainties, (ii) a stochastic optimisation model, and (iii) an appropriate solution algorithm. We propose a process to select a manageable number of uncertainties to be included in a stochastic program for SCND. We develop a comprehensive two-stage stochastic program for SCND that includes uncertainty in demand, currency exchange rates, labour costs, productivity, supplier costs, and transport costs. Also, we consider conditional value at risk (CV@R) to explore the trade-off between risk and return. We use a scenario generator based on moment matching to represent the multivariate uncertainty. The resulting stochastic integer program is computationally challenging and we propose a novel iterative solution algorithm called adaptive scenario refinement (ASR) to process the problem. We describe the rationale underlying ASR, validate it for a set of benchmark problems, and discuss the benefits of the algorithm applied to our SCND problem. Finally, we demonstrate the benefits of the proposed model in a case study and show that multiple sources of uncertainty and risk are important to consider in the SCND. Whereas in the literature most research is on demand uncertainty, our study suggests that exchange rate uncertainty is more important for the choice of optimal supply chain strategies in international production networks. The SCND model and the use of the coherent downside risk measure in the stochastic program are innovative and novel; these and the ASR solution algorithm taken together make contributions to knowledge

Managing the trade-off implications of global supply

The cost versus response trade-off is a growing logistics issue due to many markets being increasingly characterized by demand uncertainty and shorter product life cycles. This is exacerbated further with supply increasingly moving to low cost global sources. However, the poor response implications of global supply are often not addressed or even acknowledged when undertaking such decisions. Consequently, various practical approaches to minimising, postponing or otherwise managing the impact of the demand uncertainty are often only adopted retrospectively. Even though such generic solutions are documented through case examples we lack effective tools and concepts to support the proactive identification and resolution of such trade-offs. This paper reports on case-based theory building research, involving three cases from the UK and USA used in developing a conceptual model with associated tools, in support of such a process

Integrated optimisation for production capacity, raw material ordering and production planning under time and quantity uncertainties based on two case studies

Abstract This paper develops a supply chain (SC) model by integrating raw material ordering and production planning, and production capacity decisions based upon two case studies in manufacturing firms. Multiple types of uncertainties are considered; including: time-related uncertainty (that exists in lead-time and delay) and quantity-related uncertainty (that exists in information and material flows). The SC model consists of several sub-models, which are first formulated mathematically. Simulation (simulation-based stochastic approximation) and genetic algorithm tools are then developed to evaluate several non-parameterised strategies and optimise two parameterised strategies. Experiments are conducted to contrast these strategies, quantify their relative performance, and illustrate the value of information and the impact of uncertainties. These case studies provide useful insights into understanding to what degree the integrated planning model including production capacity decisions could benefit economically in different scenarios, which types of data should be shared, and how these data could be utilised to achieve a better SC system. This study provides insights for small and middle-sized firm management to make better decisions regarding production capacity issues with respect to external uncertainty and/or disruptions; e.g. trade wars and pandemics.</jats:p

Supply Chain Integration: A Case-based Investigation of Status, Barriers, and Paths to Enhancement.

In a global marketplace supply chain integration is recognised to be one of today's competitive advantages; where the aim is to optimise material- and information-flows inside the focal company and also across supply chain companies. However, many academics report that such supply chain excellence is still rare, and that guidance is missing on how supply chain integration is achieved in practise. This exploratory research utilised a stepwise methodology to investigate pathways to supply chain integration. First, a suitable investigation method was identified and further developed, before being used to assess the current status of supply chain integration in New Zealand. Next, because removal of barriers is recognised to be crucial, the internal and external barriers to supply chain integration were investigated. Finally, longitudinal case studies were used to investigate ways of supply chain integration enhancement and to develop a deeper and more complete understanding of current integration status, barriers, and ways of enhancement. In total, some 240 person days were spent in eleven different companies from multiple industry sectors to investigate supply chain integration in practise. Current practises of a large sample of New Zealand value streams were evaluated using the Quick Scan Audit Methodology. The Quick Scan Audit Methodology is carried out by a team of researchers (investigator triangulation) which utilise multiple and rigorous data collection techniques and methods (data- and method triangulation). The research revealed that supply chain integration practise rarely resembles the theoretical ideal and, similarly, seldom do available supply chain integration models reflect reality. Also, New Zealand value streams are significantly less integrated on the customer side compared to the supplier side. Further, every case company was found to face significant barriers to supply chain integration. Managerial, socio-cultural factors are the major obstacles to internal supply chain integration resulting in functional silos. Similarly, power and dependency issues limit the levels of integration achieved externally. The research revealed that good top management support and favourable external dependencies offer the best setting for enhancing supply chain integration in practise. However, if a focal company lacks top management support and/or has an unfavourable dependency structure, the focal company chooses the path of least resistance when integrating its supply chain. Also, supply chain managers and change agents address people factors and cultural change first, before addressing either internal process issues or external relationship issues; after which communication technology upgrades are addressed. Finally, this exploratory study yielded some early insights that the speed of supply chain integration development in practise follows a learning curve trajectory

The dark side of global sourcing: a systematic literature review and research agenda

Purpose: The purpose of this paper is to present a systematic review of the literature concerning the negative aspects of global sourcing (GS). It complements prior research on the positive aspects of GS, advances theoretical understanding of the phenomenon, and suggests an agenda for future research. Design/methodology/approach: The sourcing, international business and supply chain management literature is systematically reviewed and findings from 83 previous studies are investigated. Findings: Research on the downsides of GS has intensified over the last decade, but the related knowledge has been very fragmented and oftentimes latent. This literature review extracts knowledge around 28 antecedents to GS downsides from the literature and illustrates their potential harmful effects along operational and financial performance dimensions. Findings suggest that future research should focus more on the effects of decision-making biases and the effects of firm-internal barriers. The dynamic and hidden costs of GS should also be scrutinized in more depth. Originality/value: This study is the first systematic literature review of the downsides of GS. It facilitates a more balanced and nuanced picture of GS to help managers make better-informed GS decisions. The review also offers a holistic research framework that opens up avenues for much-needed research into the “dark side” of GS

Supply Chain

Traditionally supply chain management has meant factories, assembly lines, warehouses, transportation vehicles, and time sheets. Modern supply chain management is a highly complex, multidimensional problem set with virtually endless number of variables for optimization. An Internet enabled supply chain may have just-in-time delivery, precise inventory visibility, and up-to-the-minute distribution-tracking capabilities. Technology advances have enabled supply chains to become strategic weapons that can help avoid disasters, lower costs, and make money. From internal enterprise processes to external business transactions with suppliers, transporters, channels and end-users marks the wide range of challenges researchers have to handle. The aim of this book is at revealing and illustrating this diversity in terms of scientific and theoretical fundamentals, prevailing concepts as well as current practical applications