61 research outputs found
Mitigating the Bullwhip Effect and Enhancing Supply Chain Performance through Demand Information Sharing: An ARENA Simulation Study
The supply chain is a network of organizations that collaborate and leverage their resources to deliver products or services to end-customers. In today's globalized and competitive market, organizations must specialize and form partnerships to gain a competitive edge. To thrive in their respective industries, organizations need to prioritize supply chain coordination, as it is integral to their business processes. Â Â Supply chain management focuses on the collaboration of organizations within the supply chain. However, when each echelon member optimizes their goals without considering the network's impact, it leads to suboptimal performance and inefficiencies. This phenomenon is known as the Bullwhip effect, where order variability increases as it moves upstream in the supply chain. The lack of coordination, unincorporated material and information flows, and absence of ordering rules contribute to poor supply chain dynamics. To improve supply chain performance, it is crucial to align organizational activities. Previous research has proposed solutions to mitigate the Bullwhip effect, which has been a topic of intense study for many decades. This research aims to investigate the causes and mitigations of the Bullwhip effect based on existing research. Additionally, the paper utilizes ARENA simulation to examine the impact of sharing end-customer demand information. As far as we are aware, no study has been conducted to deeply simulate the bullwhip effect using the ARENA simulation. Previous studies have investigated this phenomenon, but without delving into its intricacies. The simulation results offer potential strategies to mitigate the Bullwhip effect through demand information sharing. Keywords: Supply Chain Management, Bullwhip effect, Inventory management, ARENA simulation, Information sharing, forecasting technique, Demand variability. DOI: 10.7176/JESD/14-14-07 Publication date:August 31st 202
Bullwhip effect: Modelling and simulation of a sinusoidal stimulus considering food waste
Background: The current coronavirus disease 2019 (COVID-19) pandemic has stressed why a change towards resilient, robust and sustainable supply chains is more imperative than ever. This is especially true for supply chains of perishable foods, where issues such as the bullwhip effect cause not only economic but also environmental damage.
Objectives: The key objectives of this study are to gain a deeper insight into correlations regarding the causes of the bullwhip effect and to see how a sinusoidal stimulus is affecting the generation of food waste.
Method: A simplified beef food chain was modelled in Tecnomatix Plant Simulation®. As the bullwhip effect consists of a simplified parameterisation of an excitation duration (period length) and its height (amplitude), these two variables were used to generate a sinusoidal stimulus. The simulation results were statistically verified and checked for commonalities and differences with the already established scientific knowledge.
Results: While the expected higher sensitivity of the front links of the supply chain to waste generation can be confirmed, the results of a long stimulation period suggest that the negative effects of the bullwhip effect do not increase indefinitely.
Conclusion: The analysis of the results has shown that previous theories can be transferred, but that the variation of the variables entails new insights for the interdependencies of the amplitude and period length and their influence on the output variable waste.
Contribution: The study contributes to a more holistic understanding of the bullwhip effect and, in particular, its implications within a perishable food supply chain
Product Sourcing Strategies of UK Footwear Firms
This research projects is aimed at clarifying the impact of global economic shifts on UK footwear sector firms’ future product sourcing strategies, their sourcing location decisions and how they might respond to ongoing turbulence if further contraction within the domestic industry is to be halted.
China remains the world largest exporter of footwear to the UK. They are, however, experiencing significant inflationary pressures in manufacturing such that some UK firms are considering alternative sourcing locations.
Additionally, many footwear firms seek to achieve greater supply chain (SC) agility whether outsourcing or manufacturing in order to respond more effectively to satisfying demand in increasingly fickle UK market segments and in some export markets. In this regard consideration is being given to manufacturing repatriation, however, sector expertise is becoming increasingly scarce with the resulting loss of traditional shoemaking knowledge and ‘know-how’. Given such circumstances, technological innovation may prove to be the only strategy for re-shoring to become viable.
The research will adopt both Transaction Cost Theory and the Resource Base View as both individual and complementary theoretical lens.
Comparative case studies provide the main source of data, supported by sector specialist key informant narratives in order to provide verification to the primary outputs. The primary case studies will be subjected to ‘cross case’ analysis in order to generate findings which identify critical issues relating to footwear product sourcing by UK firms. In turn they will provide a platform for the development of new SC theoretical concepts and generate usable supply chain practitioner models/ frameworks.
If adopted these new approaches to product sourcing strategy should positively impact on firm performance product sourcing efficiency, improved SC agility to halt sector decline
When bullwhip increases in the lead time: An eigenvalue analysis of ARMA demand
This is the final version. Available on open access from Elsevier via the DOI in this recordProblem definition. The impact of lead times on the bullwhip effect produced by the order-up-to (OUT) replenishment policy is studied. Practical relevance. Under general auto-regressive moving average (ARMA) demand, we investigate when the OUT policy possesses an always-increasing-in-the-lead-time bullwhip effect and when it does not. Methodology. A bullwhip measure based on the difference between the demand and order variance is combined with a novel analysis based on the eigenvalues and impulse response of the ARMA demand process. Contribution. We show a positive demand impulse response is a necessary and sufficient condition for an increasing in the lead time bullwhip effect. The ordering of zeros and poles (the eigenvalue ordering) of the z-transform transfer function of the demand process reveals when the demand impulse is positive. To provide further insight, we study ARMA(2,2) demand, which contains six different eigenvalue orderings. Two of these orderings satisfy a sufficient condition (positive demand eigenvalues in a particular order) for a positive impulse response. Two orderings satisfy the inverse of this sufficient condition and do not possess a positive impulse response. The final two orderings do not satisfy the sufficient condition, nor its inverse, but do contain positive impulse responses. Managerial implications. Our findings are important as reducing lead-times is often advocated as an improvement action to reduce the bullwhip effect. By identifying the demand characteristics that lead to a bullwhip effect that increases in the lead time we offer prescriptive advice on when, and when not, to invest in lead time reduction
The bullwhip effect: Progress, trends and directions
This is the final version. Available on open access from Elsevier via the DOI in this recordThe bullwhip effect refers to the phenomenon where order variability increases as the orders move upstream in the supply chain. This paper provides a review of the bullwhip literature which adopts empirical, experimental and analytical methodologies. Early econometric evidence of bullwhip is highlighted. Findings from empirical and experimental research are compared with analytical and simulation results. Assumptions and approximations for modelling the bullwhip effect in terms of demand, forecast, delay, replenishment policy, and coordination strategy are considered. We identify recent research trends and future research directions concerned with supply chain structure, product type, price, competition and sustainability
Internet of Things and Modern Supply Chain Management
Information flow has a great influence over the flow of materials in the supply chain industry. The behavior by which the materials flow is highly affected by how the information flows throughout the organization in a smooth manner. To develop the supply chain performance and improve the efficiency of information sharing a lot of practices have been developed to achieve that target. However nowadays with the expansion of companies and having complicated structures of communication, ordinary practices cannot suffice any longer. Additionally, a lot of time is not utilized properly wasting a lot of time and lowering the efficiency of the organization.
This research aim is to investigate the development of the internet of things and how when properly utilized it can make a huge impact on modern supply chain management. This research aim is to provide a theoretical basis on how companies can use internet of things to allow easier access for information throughout the organization with minimal effort. The research questions to be addressed in this research are (1), What is the impact of the internet of things on modern supply chain management (2) what are the possible improvements and future work that can be done with regards to the internet of things (3) is it easy to use.
An application of internet of things in the supply chain management is developed based on literature findings. The applications aim is to take place to match between execution flexibility and information abundance. Information sharing aimed should be providing high quality information for the higher ups and management before making crucial and swift decisions.
To improve the flexibility of the operations and improve the pace within the working environment information must be gathered in a swift manner. It was determined that there are several reasons behind the turbulent flow between materials flow and information flow. Numerous plan changes in response to demand changes, varying planning processes which would subsequently cause problems when designing a supply chain model to organize the information flow. Moreover, it was also found that another reason was insufficient data which resulted in the inability of sharing information between various departments
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