Does the short-selling mechanism improve energy security? Evidence from China.

Reducing carbon emissions and improving energy efficiency are essential to respond to global climate change actively. However, improving energy security under resource and environmental constraints is the key for China to achieve high-quality and sustainable development. Thus, using the panel data at the enterprises and regional levels in China from 2013 to 2020, this research develops an energy security index to study the impact of the short-selling mechanism on energy security. The results show that China's energy security is generally on the rise under the short-selling mechanism. However, it has different degrees of impact on energy security in different energy structures, supply chains, and environments. In addition, China's energy security has a regional spillover effect under the short-selling mechanism's capital pressure and supervision governance. This paper also finds that short-selling can alleviate the supply chain's bullwhip effect and risk effect. Finally, the short-selling mechanism complements the micro-influence mechanism of energy security, and short-selling positively impacts China's energy security.

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.

Two-stage supply chain inventory management based on system dynamics model for reducing bullwhip effect of sulfur product.

Bullwhip effect is prevalent in supply chains, creating supply and inventory risks that affect marketing, supply and production. However, there are limited researches on the optimization of chemical supply chain inventory management. In order to solve the above problem, this paper took the sulfur product supply chain of a sulfur plant as an example, combined with the idea of system dynamics, and systematically studied the inventory control strategy in the distributor-retailer two-level inventory system constituted by the supply chain. Firstly, the causal loop diagram was drawn according to the system relationship between variables in the two-level supply chain, and then the system dynamics model of sulfur product supply chain was formed. Finally, problems existing in the supply chain were explored through simulation, and optimization suggestions were submitted. It can be concluded from the simulation results that there was bullwhip effect in the sulfur product supply chain, and the delay of transportation time and the change of inventory adjustment time would have an impact on the inventory level of each node enterprise in the supply chain. Therefore, the method of building an information sharing platform, implementing visual information management, and adopting logistics transportation service outsourcing could enhance the information exchange among node enterprises, so as to improve the operational efficiency of the entire product supply chain.

Active management strategy for supply chain system using nonlinear control synthesis.

Nonlinear dynamical behaviours with chaotic phenomena are commonly observed in a typical logistics model and supply chain system. Bullwhip effect has been widely recognized as one of the main issues on affecting the supply chain management. In essence, this phenomenon will lead to unnecessary consumption and waste of natural and social resources by demand variability amplification as moving up in the supply chain networks. However, traditional modelling approaches may become complicated in dealing with uncertainty and chaotic behaviour that are prevalent in real supply chains. System dynamics theory has been employed as a potentially effective strategy to cope with chaotic supply chains which are unpredictable behaviours in time. Four-dimensional differential equations which exhibit chaotic behaviours are constructed to describe a multi-echelon supply chain with bullwhip effect. Furthermore, modern control theory is applied to deal with the multi-stage supply chain optimization problems against disruptions. Specifically, the novel fractional order adaptive sliding mode control (FO-ASMC) algorithm has been implemented for ensuring efficient supply chain management. In addition, the chaos synchronization scheme is implemented in an attempt to regulate the supply chain systems under the impact of extensive uncertainties caused by tumultuous real market. It is found that the chaos synchronization is effectively realised by new FO-ASMC theory to manage advanced supply chain networks. Finally, this advanced management optimization offers a new class of intelligent applications that connects demand to supply and planning to execution across the entire supply chains.

Examining the balance between efficiency and resilience in closed-loop supply chains.

We study a hybrid system where the demand of customers can be satisfied by both manufacturing new products and remanufacturing used products. To manage the serviceable inventory, we implement a proportional order-up-to (POUT) replenishment policy. In this context, we first analyse the system efficiency by assessing its capacity to meet customer demand in a cost-effective manner. To this end, we consider both inventory performance (i.e., the balance between inventory holding and stock-out costs) and production smoothness (by measuring the Bullwhip effect in the supply chain). Second, we investigate the system resilience to demand volatility. In particular, we explore the impact of demand shocks on the inventory and production of the closed-loop system. Interestingly, we find that tuning the POUT controller to optimise efficiency may be problematic in terms of resilience to demand shocks. In this sense, a key trade-off exists that needs to be carefully considered by supply chain managers. Linking efficiency to resilience in such supply chains thus becomes essential to strengthen the transition towards more circular economic models. All in all, our analysis, via control-theoretic and simulation techniques, provides professionals with valuable insights into how to identify the appropriate 'formula' for building both efficient and resilient closed-loop supply chains.

The effects of quantity discounts on supply chain performance: Looking through the Bullwhip lens.

Quantity discounts are a common pricing mechanism to stimulate large orders. We explore their impact on the dynamic behaviour of production and distribution systems by studying key operational and economic metrics. In a three-echelon supply chain, we observe that the discount generally increases the Bullwhip Effect, which especially harms the manufacturer. The discount also reduces the retailer's purchase costs, but increases its inventory- and capacity-related costs. A key trade-off thus emerges, which manifests itself through a U-shaped relationship between the total cost and the discount acceptance parameter. In the light of this trade-off, we discuss how key factors should affect the retailer's willingness to pursue the discount. We observe that managers that need to deal with tougher environmental conditions, such as high demand uncertainty and long lead times, should be less reluctant to increase orders up to the discount quantity. We also discuss in detail other valuable insights for professionals, both from the perspective of sellers and buyers.

Study on Identification Methods of Bullwhip by PCR Technology Based on Cyt b Gene / 中国药房

OBJECTIVE： To establish the method for PCR identification of bullwhip， and to identify the authenticity of bullwhip at the molecular level. METHODS： DNA samples of bullwhip and its counterfeits （donkey whip， pig whip， sheep whip） were extracted and their integrity， purity and concentration were detected. Using GenBank related information， using mitochondrial cytochrome b （Cyt b） gene of bullwhip as target gene， Primer-BLAST online software was used to design specific primer. PCR amplification was performed for whips of different species， and electrophoretic analysis was conducted for the product. PCR products of bullwhip samples were cloned and confirmed by DNA sequencing. The specificity and repeatability of the established PCR method were verified. RESULTS： DNA purity of the bullwhip and its counterfeits was high， and there was no protein or RNA pollution. 1.5％ agarose gel electrophoresis showed that there were obvious target gene bands of bullwhip samples at 200-300 bp， while no corresponding bands appeared in other counterfeit products. The results of DNA sequencing showed that the nucleotide sequence of the gene fragment of bullwhip was 100％ similar to that of the bullwhip in GeneBank. Results of methodological validation showed that established method was specific and reproducible. CONCLUSIONS： The established PCR identification method based on Cyt b gene in the study is simple， rapid， accurate， specific and reproducible， and can meet the requirements of analysis and identification of bullwhip and its counterfeits.

Brief analysis feasibility research of the application about modern supply chain management in high-value medical consumables / 中国医学装备

As an important part of medical supplies, the logistics management of high-value medical consumables becomes a key link in modern hospital administration. Compare between the management of high-value medical consumables and modern supply chain management. Based on 4R theory, discusses and analyses the management of high-value medical consumables in Fuwai hospital. By means of 4R theory, modern supply chain management has been optimized for the actual consumable management. And found out a effective method to resolve bullwhip effect caused by the limitations of high-value medical consumables. This research demonstrate modern hospital want to win the competitive initiative only by the improvement of material flow management level.