Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level...Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous.展开更多
This paper presents an adaptive path planner for unmanned aerial vehicles （UAVs） to adapt a real-time path search procedure to variations and fluctuations of UAVs’ relevant performances, with respect to sensory cap...This paper presents an adaptive path planner for unmanned aerial vehicles （UAVs） to adapt a real-time path search procedure to variations and fluctuations of UAVs’ relevant performances, with respect to sensory capability, maneuverability, and flight velocity limit. On the basis of a novel adaptability-involved problem statement, bi-level programming （BLP） and variable planning step techniques are introduced to model the necessary path planning components and then an adaptive path planner is developed for the purpose of adaptation and optimization. Additionally, both probabilistic-risk-based obstacle avoidance and performance limits are described as path search constraints to guarantee path safety and navigability. A discrete-search-based path planning solution, embedded with four optimization strategies, is especially designed for the planner to efficiently generate optimal flight paths in complex operational spaces, within which different surface-to-air missiles （SAMs） are deployed. Simulation results in challenging and stochastic scenarios firstly demonstrate the effectiveness and efficiency of the proposed planner, and then verify its great adaptability and relative stability when planning optimal paths for a UAV with changing or fluctuating performances.展开更多
We propose a stochastic level value approximation method for a quadratic integer convex minimizing problem in this paper. This method applies an importance sampling technique, and make use of the cross-entropy method ...We propose a stochastic level value approximation method for a quadratic integer convex minimizing problem in this paper. This method applies an importance sampling technique, and make use of the cross-entropy method to update the sample density functions. We also prove the asymptotic convergence of this algorithm, and report some numerical results to illuminate its effectiveness.展开更多
This paper considers two-level integer programming problems involving random fuzzy variables with cooperative behavior of the decision makers. Considering the probabilities that the decision makers’ objective functio...This paper considers two-level integer programming problems involving random fuzzy variables with cooperative behavior of the decision makers. Considering the probabilities that the decision makers’ objective function values are smaller than or equal to target variables, fuzzy goals of the decision makers are introduced. Using the fractile criteria to optimize the target variables under the condition that the degrees of possibility with respect to the attained probabilities are greater than or equal to certain permissible levels, the original random fuzzy two-level integer programming problems are reduced to deterministic ones. Through the introduction of genetic algorithms with double strings for nonlinear integer programming problems, interactive fuzzy programming to derive a satisfactory solution for the decision maker at the upper level in consideration of the cooperative relation between decision makers is presented. An illustrative numerical example demonstrates the feasibility and efficiency of the proposed method.展开更多
An algorithm is proposed in this paper for solving two-dimensional bi-level linear programming problems without making a graph. Based on the classification of constraints, algorithm removes all redundant constraints, ...An algorithm is proposed in this paper for solving two-dimensional bi-level linear programming problems without making a graph. Based on the classification of constraints, algorithm removes all redundant constraints, which eliminate the possibility of cycling and the solution of the problem is reached in a finite number of steps. Example to illustrate the method is also included in the paper.展开更多
BACKGROUND Gastric cancer(GC)and head and neck squamous cell carcinoma(HNSCC)are common malignancies with high morbidity and mortality rates.Traditional treatments often yield limited efficacy,especially in advanced c...BACKGROUND Gastric cancer(GC)and head and neck squamous cell carcinoma(HNSCC)are common malignancies with high morbidity and mortality rates.Traditional treatments often yield limited efficacy,especially in advanced cases.Recent advancements in immunotherapy,particularly immune checkpoint inhibitors targeting programmed death-ligand 1(PD-L1),have shown promise.However,the expression and interaction of pescadillo ribosomal biogenesis factor 1(PES1)and PD-L1 in these cancers remain unclear.Understanding their roles could provide new insights into tumor biology and improve therapeutic strategies.AIM To investigate the expression levels of PES1 and PD-L1 in tumor tissues of patients with GC and HNSCC.METHODS A total of 58 cases of GC and HNSCC undergoing surgical resection were selected from January 2022 to January 2024.Paraffin specimens of GC and HNSCC tissues were taken from the patients,and the sections were subjected to staining with immunohistochemistry and hematoxylin-eosin staining,and the protein expression of PES1 and PD-L1 was observed microscopically.RESULTS Among 58 GC and HNSCC tissues,30 cases were positive and 28 cases were negative for PES1 expression,and 34 cases were positive and 24 cases were negative for PD-L1 expression.The positive expression rates of PES1 and PDL1 were 51.72% and 58.62%,respectively.PES1 expression was correlated with the TNM stage,lymph node metastasis,and the depth of infiltration(P<0.05),and PD-L1 expression was correlated with the differentiation degree,lymph node metastasis,and infiltration depth(P<0.05).CONCLUSION PES1 and PD-L1 were positively expressed in GC and HNSCC tissues and correlated with clinical features.They may serve as potential biomarkers for immune-targeted therapies.展开更多
基金supported by the National Natural Science Foundationof China (70771080)the National Science Foundation of Hubei Province(20091107)Hubei Province Key Laboratory of Systems Science in Metallurgical Process (B201003)
文摘Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous.
基金the National Natural Science Foundation of China(No.60904066)
文摘This paper presents an adaptive path planner for unmanned aerial vehicles （UAVs） to adapt a real-time path search procedure to variations and fluctuations of UAVs’ relevant performances, with respect to sensory capability, maneuverability, and flight velocity limit. On the basis of a novel adaptability-involved problem statement, bi-level programming （BLP） and variable planning step techniques are introduced to model the necessary path planning components and then an adaptive path planner is developed for the purpose of adaptation and optimization. Additionally, both probabilistic-risk-based obstacle avoidance and performance limits are described as path search constraints to guarantee path safety and navigability. A discrete-search-based path planning solution, embedded with four optimization strategies, is especially designed for the planner to efficiently generate optimal flight paths in complex operational spaces, within which different surface-to-air missiles （SAMs） are deployed. Simulation results in challenging and stochastic scenarios firstly demonstrate the effectiveness and efficiency of the proposed planner, and then verify its great adaptability and relative stability when planning optimal paths for a UAV with changing or fluctuating performances.
基金Project supported by the National Natural Science Foundation of China (No.10671117)Shanghai Leading Academic Discipline Project (No.J050101)the Youth Science Foundation of Hunan Education Department of China (No.06B037)
文摘We propose a stochastic level value approximation method for a quadratic integer convex minimizing problem in this paper. This method applies an importance sampling technique, and make use of the cross-entropy method to update the sample density functions. We also prove the asymptotic convergence of this algorithm, and report some numerical results to illuminate its effectiveness.
文摘This paper considers two-level integer programming problems involving random fuzzy variables with cooperative behavior of the decision makers. Considering the probabilities that the decision makers’ objective function values are smaller than or equal to target variables, fuzzy goals of the decision makers are introduced. Using the fractile criteria to optimize the target variables under the condition that the degrees of possibility with respect to the attained probabilities are greater than or equal to certain permissible levels, the original random fuzzy two-level integer programming problems are reduced to deterministic ones. Through the introduction of genetic algorithms with double strings for nonlinear integer programming problems, interactive fuzzy programming to derive a satisfactory solution for the decision maker at the upper level in consideration of the cooperative relation between decision makers is presented. An illustrative numerical example demonstrates the feasibility and efficiency of the proposed method.
文摘An algorithm is proposed in this paper for solving two-dimensional bi-level linear programming problems without making a graph. Based on the classification of constraints, algorithm removes all redundant constraints, which eliminate the possibility of cycling and the solution of the problem is reached in a finite number of steps. Example to illustrate the method is also included in the paper.
文摘BACKGROUND Gastric cancer(GC)and head and neck squamous cell carcinoma(HNSCC)are common malignancies with high morbidity and mortality rates.Traditional treatments often yield limited efficacy,especially in advanced cases.Recent advancements in immunotherapy,particularly immune checkpoint inhibitors targeting programmed death-ligand 1(PD-L1),have shown promise.However,the expression and interaction of pescadillo ribosomal biogenesis factor 1(PES1)and PD-L1 in these cancers remain unclear.Understanding their roles could provide new insights into tumor biology and improve therapeutic strategies.AIM To investigate the expression levels of PES1 and PD-L1 in tumor tissues of patients with GC and HNSCC.METHODS A total of 58 cases of GC and HNSCC undergoing surgical resection were selected from January 2022 to January 2024.Paraffin specimens of GC and HNSCC tissues were taken from the patients,and the sections were subjected to staining with immunohistochemistry and hematoxylin-eosin staining,and the protein expression of PES1 and PD-L1 was observed microscopically.RESULTS Among 58 GC and HNSCC tissues,30 cases were positive and 28 cases were negative for PES1 expression,and 34 cases were positive and 24 cases were negative for PD-L1 expression.The positive expression rates of PES1 and PDL1 were 51.72% and 58.62%,respectively.PES1 expression was correlated with the TNM stage,lymph node metastasis,and the depth of infiltration(P<0.05),and PD-L1 expression was correlated with the differentiation degree,lymph node metastasis,and infiltration depth(P<0.05).CONCLUSION PES1 and PD-L1 were positively expressed in GC and HNSCC tissues and correlated with clinical features.They may serve as potential biomarkers for immune-targeted therapies.
