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UAV Task Allocation for Hierarchical Multiobjective Optimization in Complex Conditions Using Modified NSGA-III with Segmented Encoding

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Journal of Shanghai Jiaotong university(Science) 2021年第4期26卷 431-445页

作者： jin yudong FENG Jiabo ZHANG Weijun School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

With the recent boom in unmanned aerial vehicle (UAV) technology, many UAV applications involving complex and risky tasks in military and civilian fields have emerged, such as military strikes and disaster monitoring. Task allocation for UAVs is the process of planning the division of work among UAVs, controlled from ground stations by human operators. This study formulates the UAV task-allocation problem as an extended traveling salesman problem and presents a novel UAV task-allocation model for complex air concentration monitoring tasks. Then, an optimized non-dominated sorting genetic algorithm III (NSGA-III) based on a twin-exclusion mechanism, hierarchical objective-domination operator, and segmented gene encoding (i.e., NSGA-III-TEHOD) is developed to solve complex task-allocation problems involving multiple UAVs, hierarchical objectives, obstacles, and ambient wind. The algorithm is tested in several simulations, and the results demonstrate that the new algorithm outperforms NSGA-III, non-dominated sorting genetic algorithm II (NSGA-II), and genetic algorithm (GA) in terms of efficiency of global convergence and early maturation prevention and is available for the hierarchical objective-optimization problems.

关键词： unmanned aerial vehicle(UAV) task allocation non-dominated sorting genetic algorithm(NSGA) multiobjective optimization

Discovery of Late Jurassic Sporopollen Assemblage from the Tamulangou Formation in the Hongqi Sag of the Hailar Basin,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1718-1720页

作者： WAN Chuanbiao XUE Yunfei SUN Yuewu HOU Yanping jin yudong ZHANG Xin LI Ti Exploration and Development Research Institute of Daqing Oilfield Company Ltd. DaqingHeilongjiang 163712China Key Laboratory for Evolution of Past Life and Environment in Northeast Asian(Jilin University) Ministry of EducationChangchun 130026China

Objective The Hailar Basin is situated in the northwestern margin of the Jiamusi-Mongolia *** was a continent marginal basin to the south of the Mongolia-Okhotsk Ocean during the Jurassic and *** basement of the basin... 详细信息

关键词： Jurassic basin Basin

UHPC加固钢筋混凝土T梁的抗弯承载力计算

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混凝土与水泥制品 2024年第5期 46-50页

作者：靳玉栋陈聪刘鹤郭玉鹏亓兴军济青高速铁路有限公司山东济南250102 山东建筑大学交通工程学院山东济南205101

综合考虑结构设计原理与现行桥梁加固规范,推导了UHPC加固钢筋混凝土T梁的抗弯承载力基本假定及计算公式,采用非线性有限元软件建立了试件的三维实体模型,进行了四点弯曲模拟试验,并对比分析了理论公式计算值与数值模拟试验值。结果表明... 详细信息

综合考虑结构设计原理与现行桥梁加固规范,推导了UHPC加固钢筋混凝土T梁的抗弯承载力基本假定及计算公式,采用非线性有限元软件建立了试件的三维实体模型,进行了四点弯曲模拟试验,并对比分析了理论公式计算值与数值模拟试验值。结果表明:在截面高度增加10~20 cm的情况下,UHPC加固试件的抗弯承载力有显著提升;加固试件的抗弯承载力数值模拟试验值均大于理论计算值,平均相对误差为14.4%,理论公式具有一定的安全储备;推导的理论计算公式能简单、快速地预测试件的抗弯承载力,可为UHPC加固钢筋混凝土T梁的理论计算与工程应用提供参考。

关键词：加固超高性能混凝土(UHPC) T梁抗弯承载力理论计算

内镜下鼻胆管引流术与经皮肝穿刺胆道引流术治疗急性梗阻性化脓性胆管炎的效果对比

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中国医学创新 2024年第22期21卷 63-67页

作者：熊日晖陈伟力吴兆平金煜东九江市第一人民医院肝胆胰外一科江西九江332000

目的:探究内镜下鼻胆管引流术(ENBD)与经皮肝穿刺胆道引流术(PTCD)治疗急性梗阻性化脓性胆管炎(AOSC)的效果。方法:回顾性分析2021年1月—2023年12月在九江市第一人民医院治疗的94例AOSC患者的病历资料,按照手术方式不同分为两组,各47例... 详细信息

目的:探究内镜下鼻胆管引流术(ENBD)与经皮肝穿刺胆道引流术(PTCD)治疗急性梗阻性化脓性胆管炎(AOSC)的效果。方法:回顾性分析2021年1月—2023年12月在九江市第一人民医院治疗的94例AOSC患者的病历资料,按照手术方式不同分为两组,各47例;对照组接受ENBD治疗,观察组接受PTCD治疗。观察两组临床疗效、炎症反应、肝脏生化指标及并发症发生率。结果:两组治疗总有效率比较,差异无统计学意义(P>0.05)。治疗前,两组白细胞(WBC)、C反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)、白细胞介素-2(IL-2)、白细胞介素-6(IL-6)、降钙素原(PCT)、血乳酸(Lac)、总胆红素(TBIL)、直接胆红素(DBIL)、间接胆红素(IBIL)、天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)水平比较,差异均无统计学意义(P>0.05);治疗后,两组WBC、CRP、TNF-α、IL-1、IL-2、IL-6、PCT、Lac、TBIL、DBIL、IBIL、AST、ALT均低于治疗前,且观察组均低于对照组,差异均有统计学意义(P<0.05)。观察组并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论:ENBD与PTCD治疗AOSC效果相当,但PTCD可减轻炎症反应及肝功能损伤,降低并发症发生率。

关键词：内镜下鼻胆管引流术经皮肝穿刺胆道引流术急性梗阻性化脓性胆管炎肝功能

Sporopollen Assemblages from the Cretaceous Yimin Formation of the Hailar Basin,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2005年第4期79卷 459-470页

作者： WAN Chuanbiao QIAO Xiuyun XU Yanbin SUN Yuewu REN Yanguang jin yudong GAO Ping LIU Tongyan Exploration and Development Research Institute of Daqing Oilfield Company Ltd. Daqing Heilongjiang 163712 College of Earth Sciences Jilin University Changchun Jilin 130061 Research Center of Paleontology and Stratigraphy Jilin University Changchun Jilin 130026

Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are （in ascending order）： the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.

关键词： Cretaceous Barremian-Early Albian sporopollen assemblage angiosperms Hailar Basin Inner Mongolia

Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer

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Defence Technology（防务技术） 2024年第2期32卷 412-429页

作者： Wenxue Chen yudong Hu Changsheng Gao Ruoming An School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost ***,the velocity control in such trajectory tracking guidance systems of missiles is *** our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking *** global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional ***,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid ***,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify *** obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots.

关键词： BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system

Nanozyme-activating prodrug therapies:A review

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Chinese Chemical Letters 2024年第2期35卷 138-150页

作者： yudong Wu Wujun Chen Chao Wang Dongming Xing The Affiliated Hospital of Qingdao University Qingdao UniversityQingdao 266071China School of Life Sciences Tsinghua UniversityBeijing 100084China

Enzyme prodrug therapies(EPTs)have been intensively explored as attractive approaches to selective activation of systemically administered benign prodrugs by the exogenous enzymes or enzymes expressed at the desired target site,thus achieving localized,site-specific therapeutic *** effective strategies(e.g.,antibody-,viral-,gene-,as well as polymer-directed EPT)have been developed for enzyme localization to locally activate systemically administered benign ***,intrinsic limitations(e.g.,complex intracellular environment and catalyst instability)make the practical application of EPT strategies a task that presents itself as highly *** a promising alternative to natural enzyme,nanozyme has attracted substantial attention since its discovery in 2007,mainly due to the advantages of robust catalytic activity,high stability,low cost,and facile ***,nanozyme-activated prodrug strategies bring a new opportunity for targeted therapy,referred to as nanozyme-activating prodrug *** review focuses on recently reported nanozyme-activated prodrug strategies,aiming to provide some new insights into the potential applications in site-specific drug synthesis.

关键词： Enzyme prodrug therapy Nanozyme Prodrug activation Chemotherapy Drug synthesis

A versatile volume-based modeling technique of distributed local quadratic convergence for aeroengines

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Propulsion and Power Research 2024年第1期13卷 46-63页

作者： yudong Liu Min Chen Hailong Tang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

For advanced aero-engine design and research,modeling and simulation in a digital environment is indispensable,especially for engines of complicated conﬁgurations,such as var-iable cycle engines(VCE)and adaptive cycle engines(ACE).Also,in the research of future smart engines,reliable real-time digital twins are ***,the 2 dominant methods that used in solving the simulation models,Newton-Raphson(N-R)method and volume-based method,are not fully qualiﬁed for the study requirements,because neither of them reaches the satisfactory balance of convergence rate and calculating efﬁ*** this study,by deeply analyzing the mathematical principle of these 2 methods,a novel modeling and solving method for aero-engine simulation,which integrates the advantages of both N-R and volume-based methods,is *** has distributed architecture and local quadratic convergence *** a novel modeling method for variable area bypass injectors(VABI)is put *** facilitate simulation of various conﬁgurations of *** modeling cases,including a high bypass-ratio(BPR)turbofan and an ACE,illustrate that the novel technique decreases the iterations by about two-thirds comparing with volume-based method,while the success rate of convergence remains over 99%.This proves its superiority in both convergence and calculating efﬁciency over the conventional *** technique can be used in advanced gas turbine en-gine design and control strategy optimization,and study of digital twins.

关键词： Aero-engine performance simulation Variable cycle engine Variable area bypass injector Digital twin Newton-Raphson method

Noise-tolerate and adaptive coefficient zeroing neural network for solving dynamic matrix square root

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 167-177页

作者： Xiuchun Xiao Chengze Jiang Qixiang Mei yudong Zhang School of Electronics and Information Engineering Guangdong Ocean UniversityZhanjiangChina School of Cyber Science and Engineering Southeast UniversityNanjingChina School of Computing and Mathematical Sciences University of LeicesterLeicesterUK

The solving of dynamic matrix square root(DMSR)problems is frequently encountered in many scientific and engineering *** the original zeroing neural network is powerful for solving the DMSR,it cannot vanish the influence of the noise perturbations,and its constant-coefficient design scheme cannot accelerate the convergence ***,a noise-tolerate and adaptive coefficient zeroing neural network(NTACZNN)is raised to enhance the robust noise immunity performance and accelerate the conver-gence speed ***,the global convergence and robustness of the pro-posed NTACZNN are theoretically analysed under an ideal environment and noise-perturbed ***,some illustrative simulation examples are designed and performed in order to substantiate the efficacy and advantage of the NTACZNN for the DMSR problem *** with some existing ZNNs,the proposed NTACZNN possesses advanced performance in terms of noise tolerance,solution accuracy,and convergence rate.

关键词： adaptive intelligent systems neural network real-time systems