Process planning is a typical combinatorial optimization problem. When the scale of the problem increases, combinatorial explosion occurs, which makes it difficult for traditional precise algorithms to solve the problem. A hybrid particle swarm optimization (HPSO) algorithm is proposed in this paper to solve problems of process planning. A hierarchical coding method including operation layer, machine layer and logic layer is designed in this algorithm. Each layer of coding corresponds to the decision of a sub-problem of process planning. Several genetic operators of the genetic algorithm are designed to replace the update formula of particle position and velocity in the particle swarm optimization algorithm. The results of the benchmark example in case study show that the algorithm proposed in this paper has better performance.
To coordinate the supply chain risk caused by demand uncertainty, this paper proposed a flexible return strategy under demand uncertainty, in which the retailer can choose return quantity independently by put option after the selling season, while the return quantity is usually determined by the supplier in the classical return strategy. In our novel return strategy, the exercise price is not fixed, and we developed the base model of this strategy, named the selective buyback contracts model. We have solved the optimal pricing and ordering strategies of supply chain members. Numerical studies demonstrated that the contracts can coordinate a supply chain with one retailer and one supplier, and the supplier can adjust the profit distribution of the supply chain by adjusting the option exercise price. Compared with other return strategies, the selective buyback contracts give the retailer more power of choice, and the supplier receives risk compensation from the put options.
The evaluation of entrepreneurs’ uncertainty tolerance (UT) is more meaningful, e.g., predicting their behaviors, making psychological counseling strategies for them, etc. In fact, it is an uncertain problem that simultaneously contains randomness and fuzziness in evaluating entrepreneurs’ UT. Hence, it is difficult to solve it by traditional evaluation methods. This paper presents a cloud model-based comprehensive evaluation method for entrepreneurs’ UT which overcomes the inability of other methods to take into account randomness and fuzziness simultaneously. First, five UT levels are divided. Then, an evaluation index system which contains 14 secondary level indexes and four primary level indexes is constructed, and an analytic hierarchy process (AHP) method is used to obtain the weights for the secondary level indexes. Subsequently, the backward cloud generator (BCG) and virtual cloud model (CM) are used to obtain the CM of evaluation indexes, and cloud chart of evaluation results are generated by forward cloud generator (FCG). Finally, five core start-up founders of a high-tech company in China are chosen for a case study to illustrate our method. Compared with other traditional evaluation methods, our method has been verified to be a more competitive method. Its results are more visualized and low information lost.
In the supply chain network frequently facing disruption risk, sustaining a high reputation is essential for ensuring long-term sustainability. While existing studies have investigated how reputation evidence influences the overall network structure and cooperative behaviors, they have not extensively examined how variations in reputation evidence affect cooperative dynamics in the bipartite graph consisting of upstream and downstream enterprises. To bridge this gap, our research introduces a novel, reputation-based approach utilizing evidential reasoning theory to assess dynamic environments prone to disruption risk. This improved approach assigns specific weights and reliability to reputation evidence. In this article, we analyze the evolution of cooperation between upstream and downstream enterprises in the supply chain, considering varied distributions of reputation evidence. We also conduct numerical simulations to evaluate the impact of these reputation distributions on the cooperative evolution of the supply chain network under diverse disruption scenarios, including both direct and indirect risks. Our findings offer insightful guidance for managers to refine their reputation distribution strategies, effectively navigate different disruption risk scenarios, and lessen negative impacts on cooperation. Moreover, our study provides significant implications for partner selection and managing disruption risk in a dynamic and uncertain supply chain network.
30 May 2025 in International Journal of Modern Physics C