Bullwhip effect: Modelling and simulation osinusoidal 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. © 2023. The Authors. Licensee: AOSIS. This work is licensed under the Creative Commons Attribution License.

The moderating role of vendor managed inventory on the bullwhip effect in the COVID-19 pandemic

The study sought to determine the role of vendor-managed inventory and form postponement in mitigating against the bullwhip effect in the bakery industry. The bullwhip effect is referred to as demand distortions along the upstream supply chain that is caused by variances between supply and demand. The bullwhip effect was conceptualized by its indicators that are overstocking, obsolescence, and inventory holding costs. A survey of conveniently chosen 100 bakeries was conducted in the city of Harare, the capital city of Zimbabwe. The informants for individual bakeries were competent bookkeepers or qualified accountants. A factorial MANOVA and follow-up ANOVAs using the Bonferroni method were conducted. The study indicated statistically significant main effects and interaction effects for all the factors and concluded that all the indicators of the bullwhip effect can be mitigated if bakery businesses pursued either or both of the vendor-management inventory and the form postponement strategies. The managerial implications of this study were that bakery businesses can avoid the consequences of the bullwhip effect through investing in plant and equipment that enables form postponement, and strengthen the widely practiced vendor-management strategy.

Product availability and stockpiling in times of pandemic: causes of supply chain disruptions and preventive measures in retailing.

The coronavirus pandemic in 2020 brought global supply chain disruptions for retailers responding to the increased demand of consumers for popular merchandise. There is a need to adapt the existing supply chain models to describe the disruptions and offer the potential measures that businesses and governments can take to minimize adverse effects from a retail logistics perspective. This research analyses the possible reasons for supply and demand disruptions using a mathematical model of a retail supply chain with uncertain lead times and stochastic demand of strategic consumers. The established concepts of supply chain management are applied for the model analysis: multi-period inventory policies, bullwhip effect, and strategic consumers. The impact of the pandemic outbreaks in the model is two-fold: increased lead-time uncertainty affects supply, while consumer stockpiling affects demand. Consumers' rational hoarding and irrational panic buying significantly increase retailers' costs due to higher safety stock and demand variability. The bullwhip effect further exacerbates the disruption. The research contributes to the recent literature on business response to supply chain disruptions by developing a model where both retailers and consumers decide on the order quantity and reorder point during a pandemic outbreak. Buying limits, continuous inventory review, government rationing, substitutability, and omnichannel fulfillment are the measures that can limit the damage of supply chain disruptions from stockpiling during the pandemic. Effective communication and price and availability guarantees can mitigate the negative impact of panic buying.

Blockchain Technology as a Solution to the Bullwhip Effect

The Covid-19 Pandemic has revealed the fragility and shortcomings of existing supply chains and the importance of digitalization and digital solutions for Supply chains. In this study, a solution proposal is presented to the problem of the Bullwhip effect, which is a serious problem for Supply Chain management performance. It will be emphasized that the operational and tactical capabilities provided by Blockchain technology, which is one of the digital solutions and offered as a solution proposal, may increase the performance of the Supply Chain by providing a solution to the bullwhip effect. In addition, in this study, the thematic analyses created as a result of expert opinions on this subject and other analyses and findings related to the study will be shared. The main purpose of the research is to provide a deep understanding of the ability of Blockchain Technology to provide a solution to the problem of the bullwhip effect, which is a serious problem for the successful management of the supply chain and constitutes a starting point for the studies to be done on this subject. © Peter Lang GmbH.

Effect of Supply Chain Disruption in Dental Practice During Covid-19 Pandemic: An Indian Perspective

Disruption during Covid-19 pandemic highlighted the need of healthcare supply chain management in order to achieve effective delivery of health services. Though, considerable efforts have been undertaken on managing the healthcare supply chain disruptions in India but there is paucity of literature which documented the effect of supply chain disruptions in dental practices during covid-19 pandemic. During pandemic, the disruptions in production and distribution of dental products were seen in India. Indian dental market is largely dependent on imports and there is scarcity of local production units. The main dental companies reported significant decline in production during the first wave of Covid-19. The increase in demand for dental supplies was seen with shutdown, shortage of labour and scarcity of raw materials. Disruption rippled through the supply chain and this was caused by large distortion in demand. This phenomenon led to bullwhip effect. This bullwhip effect crisis led to increased cost in dental practices. Covid19 has shown significant lack of resilience in Indian dental healthcare supply chain. This study identified few loopholes in dental supply chain and suggested the way forward for managing the supply chain disruptions. It seems that there is need of more comprehensive research on dental supply chain resilience from Indian perspective to prevent disruptions particularly in emergent situations. © 2022, MedSci Publications. All rights reserved.

Analysing the COVID-19 disruptive impact on Montevideo's Supply Chains

Globally, COVID-19 reached unprecedented levels of contagion, affecting the social meetings, public spaces, and many everyday aspects. During the first days of the pandemic, supply chains were severely impacted by a great uncertainty in socio-economic terms, causing irrational variations and the inability to forecast demand. In this paper, the effect of the COVID-19 pandemic on the behaviour of different companies is analysed based on the variation in supply and demand of consumer-packaged goods. The pandemic outbreak disruption, the bullwhip effect caused by demand fluctuations, and the resilience of different companies were studied. A multiple case study methodology is used to analyse the decision-making process of fourteen different companies, from diverse sectors in Uruguay, affronting the pandemic. The paper's main findings include the identification of disruption and operation risks along with coordination in supply chain management during the first four months of the pandemic. Moreover, due to the necessity of sanitation and comestibles, and the fear of stockout, consumers' demand was uncertain, and the bullwhip effect was observed in critical channels of some products. Finally, the resiliency and robustness of the affected companies were studied and good practices for a resilient and robust response to the pandemic were identified and analysed.

The implications of COVID-19: Bullwhip and ripple effects in global supply chains

Using the financial proxies in the efficient market hypothesis (EMH), we explore how the bullwhip effect (BWE) and ripple effect (RE) have been affected by the COVID-19 pandemic upstream and downstream. We developed two models to help us understand the phenomenon. The first model we created was the global airline stock index (GASI). This index represents all the global airline companies in the sample in one single node. We compared the GASI with each sample's buyer and supplier. The first result we observed was that some companies are more affected than others. We also found that the RE increased after the COVID-19 pandemic, but not the BWE. We then created a second model to analyze the difference in effects between companies. This reveals that the number of relationships in the supply chain network is positively related to the BWE and the RE. According to the regression analysis, the data also show that companies with a higher degree of operating level (DOL) and debts, and a lower share price, are the most vulnerable to the BWE and RE. We close by summarizing our findings and discussing future research opportunities.

Reconfiguring a hierarchical supply chain model under pandemic using text mining and social media analysis

Purpose: This study is to reconfigure a hierarchical supply chain model utilizing databases and text files to understand future pathways due to COVID-19 pandemic has had a bullwhip effect, disrupting the global supply chain, and a mechanism is needed to address this disruptive event under pandemic uncertainties. Design/methodology/approach: To address this mechanism, this study employs bibliometric analysis and text mining to reconfigure a hierarchical supply chain model under pandemic conditions and associates it with social media to conduct an intuitive visual analysis. Findings: The current academic concerns are related to an overconcentration on risk management and a data-driven approach, generating an enormous gap between the concerns of academics and those of the public. The evidence shows that for both countries with outstanding performance and those that need improvement, the efficiency in terms of preventing the spread of the pandemic should be promoted. Originality/value: This study contributes to (1) reconfiguring a hierarchical supply chain model under pandemic uncertainties and (2) bridging theory and practice by offering comparable interrelated attributes to guide post-COVID-19 strategies in the supply chain. The findings are that the supply management approach and big data are attributes that involve the concerns of world public and academics under pandemic uncertainties. © 2021, Emerald Publishing Limited.