1 Summary With the advancement of science and technology,complex engineering structures are widely used in extreme environments[1].In equipment service,many uncertainty factors significantly affect safety and reliabil...1 Summary With the advancement of science and technology,complex engineering structures are widely used in extreme environments[1].In equipment service,many uncertainty factors significantly affect safety and reliability[2–5].Therefore,ensuring high reliability of structures has become an important research direction in engineering design.At the same time,the importance of equipment health management of complex engineering structures is becoming increasingly prominent[6–8].Computer-aided uncertainty modeling and reliability assessment have become key tools,and finite element simulation and algorithmic innovation play a key role in the reliability analysis of complex equipment[9,10].These techniques can accurately simulate stress and damage accumulation under various operating environments,providing engineers with important decision support and optimization solutions.展开更多
目的探讨血清涎液化糖链抗原(Krebs Von den Lungen-6,KL-6)在新型冠状病毒感染患者中的临床价值,以期为获得对该病更好的临床决策和治疗提供参考。方法选取收治于我院的新型冠状病毒感染患者90例,根据纳入及排出标准,最终纳入轻症组71...目的探讨血清涎液化糖链抗原(Krebs Von den Lungen-6,KL-6)在新型冠状病毒感染患者中的临床价值,以期为获得对该病更好的临床决策和治疗提供参考。方法选取收治于我院的新型冠状病毒感染患者90例,根据纳入及排出标准,最终纳入轻症组71例(轻型/普通型)、重症组8例(重型/危重型),同时匹配85例健康体检者作为对照组,回顾性分析实验室和影像学检查指标。结果(1)轻症组患者入院时C反应蛋白(CRP)、白介素-6(IL-6)、KL-6、乳酸脱氢酶(LDH)和血清铁蛋白(SF)均高于对照组,而白细胞计数(WBC)和淋巴细胞计数(Lym)则低于对照组。(2)重症组CRP、IL-6、KL-6、LDH及肺炎指数高于轻症组,而Lym低于轻症组。(3)Logistic回归分析发现KL-6和LDH的升高以及Lym的降低为新冠病毒感染的独立危险因素。(4)KL-6、Lym、CRP、LDH、IL-6、肺炎指数对于重/危重型COVID-19均具有较好的预测价值。(5)KL-6与肺炎指数随着病情的缓解均出现整体降低的变化,并呈现出一定的正相关变化趋势。结论KL-6在新冠病毒感染患者中有不同程度增高,对预测重症以及判断肺部受累情况有一定的适用价值。展开更多
This paper proposes an effective reliability design optimizationmethod for fail-safe topology optimization(FSTO)considering uncertainty based on the moving morphable bars method to establish the ideal balance between ...This paper proposes an effective reliability design optimizationmethod for fail-safe topology optimization(FSTO)considering uncertainty based on the moving morphable bars method to establish the ideal balance between cost and robustness,reliability and structural safety.To this end,a performancemeasure approach(PMA)-based doubleloop optimization algorithmis developed tominimize the relative volume percentage while achieving the reliability criterion.To ensure the compliance value of the worst failure case can better approximate the quantified design requirement,a p-norm constraint approach with correction parameter is introduced.Finally,the significance of accounting for uncertainty in the fail-safe design is illustrated by contrasting the findings of the proposed reliabilitybased topology optimization(RBTO)method with those of the deterministic design method in three typical examples.Monte Carlo simulation shows that the relative error of the reliability index of the optimized structure does not exceed 3%.展开更多
Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)...Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element analysis.The full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence rate.Then,the population is classified,and different populations are updated by modified FA and SCA respectively.Besides,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population diversity.Elitist selection technique is applied to save the promising solutions and further improve the convergence rate.Moreover,the adaptive penalty function is employed to deal with the constraints.Finally,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency constraints.The results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints.展开更多
基金fundings from Project ATE:Agenda para a Transição Energética(02/C05-i01.02/2022.PC644914747-00000023)cofinanced by Plano de Recuperação e Resiliência(PRR),República Portuguesa,through NextGeneration EU+3 种基金the project entitled Giga-Cycle Fatigue Behaviour of Engineering Metallic Alloys(PTDC/EME-EME/7678/2020)National Natural Science Foundation of China(Grant No.12372195)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2022A1515240010)China Scholarship Council(No.202406070043).
文摘1 Summary With the advancement of science and technology,complex engineering structures are widely used in extreme environments[1].In equipment service,many uncertainty factors significantly affect safety and reliability[2–5].Therefore,ensuring high reliability of structures has become an important research direction in engineering design.At the same time,the importance of equipment health management of complex engineering structures is becoming increasingly prominent[6–8].Computer-aided uncertainty modeling and reliability assessment have become key tools,and finite element simulation and algorithmic innovation play a key role in the reliability analysis of complex equipment[9,10].These techniques can accurately simulate stress and damage accumulation under various operating environments,providing engineers with important decision support and optimization solutions.
文摘目的探讨血清涎液化糖链抗原(Krebs Von den Lungen-6,KL-6)在新型冠状病毒感染患者中的临床价值,以期为获得对该病更好的临床决策和治疗提供参考。方法选取收治于我院的新型冠状病毒感染患者90例,根据纳入及排出标准,最终纳入轻症组71例(轻型/普通型)、重症组8例(重型/危重型),同时匹配85例健康体检者作为对照组,回顾性分析实验室和影像学检查指标。结果(1)轻症组患者入院时C反应蛋白(CRP)、白介素-6(IL-6)、KL-6、乳酸脱氢酶(LDH)和血清铁蛋白(SF)均高于对照组,而白细胞计数(WBC)和淋巴细胞计数(Lym)则低于对照组。(2)重症组CRP、IL-6、KL-6、LDH及肺炎指数高于轻症组,而Lym低于轻症组。(3)Logistic回归分析发现KL-6和LDH的升高以及Lym的降低为新冠病毒感染的独立危险因素。(4)KL-6、Lym、CRP、LDH、IL-6、肺炎指数对于重/危重型COVID-19均具有较好的预测价值。(5)KL-6与肺炎指数随着病情的缓解均出现整体降低的变化,并呈现出一定的正相关变化趋势。结论KL-6在新冠病毒感染患者中有不同程度增高,对预测重症以及判断肺部受累情况有一定的适用价值。
基金supported by the National Natural Science Foundation of China(Grant No.12172114)Natural Science Foundation of Anhui Province(Grant No.2008085QA21)+1 种基金Fundamental Research Funds for the Central Universities(Grant No.JZ2022HGTB0291)China Postdoctoral Science Foundation(Grant No.2022M712358).
文摘This paper proposes an effective reliability design optimizationmethod for fail-safe topology optimization(FSTO)considering uncertainty based on the moving morphable bars method to establish the ideal balance between cost and robustness,reliability and structural safety.To this end,a performancemeasure approach(PMA)-based doubleloop optimization algorithmis developed tominimize the relative volume percentage while achieving the reliability criterion.To ensure the compliance value of the worst failure case can better approximate the quantified design requirement,a p-norm constraint approach with correction parameter is introduced.Finally,the significance of accounting for uncertainty in the fail-safe design is illustrated by contrasting the findings of the proposed reliabilitybased topology optimization(RBTO)method with those of the deterministic design method in three typical examples.Monte Carlo simulation shows that the relative error of the reliability index of the optimized structure does not exceed 3%.
基金supported by the NationalNatural Science Foundation of China(No.11672098).
文摘Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element analysis.The full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence rate.Then,the population is classified,and different populations are updated by modified FA and SCA respectively.Besides,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population diversity.Elitist selection technique is applied to save the promising solutions and further improve the convergence rate.Moreover,the adaptive penalty function is employed to deal with the constraints.Finally,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency constraints.The results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints.
