This paper considers a supply chain in which an upstream supplier sells a component to a downstream manufacturer facing a price and quality sensitive demand. The supplier has a chance to make investment in the manufacturer, which can not only enable the supplier to hold equity shares in the manufacturer and thus achieve profit sharing with the manufacturer, but also provide resources for the manufacturer to improve its product quality. Under any given investment strategy of the supplier, the equilibrium decisions of the two chain members on wholesale price and profit margin are characterized. Then, the supplier's optimal investment strategy is derived. The paper considers three competition models: supplier Stackelberg (SS), manufacturer Stackelberg (MS), and vertical Nash (VN) models, which correspond to different market power structures. The paper shows that the investment can always increase the market demand. Moreover, in both the SS and VN models, the value of the supplier's investment for the entire supply chain, comes from not only the quality improvement but also the profit sharing caused by equity holding; while in the MS model, the investment value comes only from the quality improvement.

This paper takes the two subsystems of inland ports and industries along the Yangtze River as a composite system as a research object, providing insight into the influence of the development efficiency of inland ports along the Yangtze River and the coupling and synergy degree of industry. Firstly, the coupling synergy effect of the inland port industry is qualitatively expounded, and secondly, the entropy weight TOPSIS method is used to construct a coupling coordination model to analyze the measurement of the development efficiency and industrial coupling synergy relationship between inland ports along the Yangtze River. Twelve cities along the Yangtze River were selected as examples, the coupling synergy degree of their ports was evaluated by referring to the comprehensive port development synergy index from 2010 to 2019, and the development levels and evolution processes of the different cities were compared and analyzed. The coupling synergy development of the inland port industry along the Yangtze River can provide a basis for the problems and countermeasures faced by the integrated development of the inland port industry along the Yangtze River.

This paper considers a multinational green supply chain (MGSC), composed of a manufacturer and a foreign retailer affected by import tariff. The main theme of this paper is to explore supply chain decisions and coordination contract. Four decision models were investigated: (1) the centralized decision supply chain model (model CS), (2) the decentralized decision supply chain model (model DS), (3) the R&D cost sharing contract model (model RD) with the retailer sharing a portion of green R&D cost, and (4) the quantity discount-cost sharing contract model (model QD), which combined a quantity discount contract with a cost sharing contract. The equilibrium decisions of these models were derived. The R&D cost sharing contract was found to improve greenness and performance of the supply chain but cannot reach the optimal performance compared to the centralized decision model. While the quantity discount-cost sharing contract can achieve a perfect coordination of MGSC. Furthermore, import tariff has an adverse effect on the performance of MGSC. The increase in tariff shrinks the threshold of the highest wholesale price and quantity discount coefficient offered by the manufacturer, which will hamper the cooperation of supply chain. However, the enhancement of consumers’ green preference is conducive to encourage the retailer to participate in cooperation and smoothen the adverse effects of tariff fluctuation. In the same model, the adverse effect of tariff on product greenness and the retail price does not change with the increase in its value. However, the adverse effect on the green performance price ratio and the profits from all parties in the supply chain are slow.

In this paper, we consider joint decisions on inventory rationing and replenishment from a regular supplier or a backup supplier with two classes of customers. When the on-hand inventory falls below a certain critical level, an inventory rationing policy is implemented to reject lower priority customers. We investigated the potential use of a backup supplier as a response to inventory rationing policy. First, we establish an inventory level transition equilibrium equation for the steady-state inventory level probability distributions and derive analytical steady-state performance indicators. Next, the inventory cost function and the nonlinear optimization model are characterized. We use real-coded genetic algorithm (RCGA) to search for the optimal joint decisions. Finally, the proposed algorithm and the joint decisions are investigated with different inventory service polices through numerical experiments. The results show that the inventory rationing policy (IRP) is superior to the traditional priority service policy (CPSP) and the common first-come-first service policy (FCFSP). The backup supply can reduce inventory costs with high arrival intensity.

Purpose: This study examines how China's dual-credit policy shapes research and development (R&D) and marketing choices in a battery electric vehicle (BEV) supply chain and identifies when different strategy combinations are preferred. Design/methodology/approach: We develop a Stackelberg game with one BEV manufacturer and one seller. The manufacturer chooses driving-range-oriented R&D or quality-oriented improvement and sets the wholesale price. The seller then decides whether to undertake marketing and sets the retail price. Demand depends on price, driving range, quality, and marketing effort, while the policy is represented by the credit trading price and a range-related credit rule. Findings: Both R&D strategies expand BEV demand, and marketing amplifies this effect. However, high marketing sensitivity can induce costly effort and tighter margins, making the seller better off foregoing marketing and free riding on demand generated by the manufacturer's improvement. Quality improvement is preferred when the credit price or range sensitivity is low. Otherwise, range-oriented R&D is optimal. The credit trading price directly reshapes the manufacturer's improvement choice and can also affect the seller's marketing threshold under driving-range-oriented R&D. Research limitations/implications: To keep the manufacturer + seller interaction under the dual-credit policy as transparent as possible, we adopt a stylized setting with one manufacturer and one seller. This parsimonious structure helps separate the core trade-offs between R&D direction and marketing effort and allows us to derive simple decision rules that can be used as a benchmark. We also use a tractable demand specification and treat the credit trading price as an external signal to maintain analytical clarity. These choices abstract from competition, consumer heterogeneity, and dynamic adjustments, which are natural directions for future extensions. Practical implications: Managers can treat the dual-credit market as an operating signal rather than a background policy. Track the credit trading price regularly and update the R&D focus accordingly. When credits become more valuable and customers care about range, prioritize range-related R&D; when that signal weakens or quality improvement is cheaper, shift the budget to quality. On the retail side, invest in marketing only when the expected margin lift covers the effort cost, and target messages that match the chosen R&D focus (range or quality). A joint quarterly plan helps avoid misaligned decisions. Social implications: Clear credit signals can speed up EV adoption by steering firms toward attributes customers value. When range incentives are strong, firms are more likely to reduce range anxiety, which can help hesitant buyers switch to EVs. When quality innovation is more efficient, firms can improve reliability and user experience, reducing complaints and waste from premature replacement. The risk is one-sided innovation if policy rewards only a single attribute. Regulators can use these insights to balance credit rules so that both usable range and product quality improve, supporting consumer welfare and decarbonization. Originality/value: This study treats the dual-credit mechanism as an R&D-related revenue channel. It distinguishes driving-range-oriented R&D from quality-oriented improvement and jointly models the manufacturer's improvement choice and the seller's marketing decision. It further identifies the threshold conditions under which the manufacturer switches between the two improvement paths and the seller forgoes marketing and free rides on the demand generated by the manufacturer's improvement effort. These findings provide guidance for BEV technology and marketing decisions.