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An improved interval model updating method via adaptive Kriging models

Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 497-514页

作者： sha wei Yifeng CHEN Hu DING Liqun CHEN shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample ***,the surrogate model in IMU methods mostly adopts the one-time construction *** makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU ***,an improved IMU method via the adaptive Kriging models is *** method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey *** optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is *** the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity *** sampling is then performed in key subspaces based on the maximum mean square error(MMSE)*** interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy *** effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical *** results show that the updated results of the interval model are in good agreement with the experimental results.

关键词： interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number

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Recent progress of gastroesophageal reflux after endoscopic myotomy

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World Journal of Gastroenterology 2024年第34期30卷 3926-3928页

作者： Xuan Yan wei-Hong sha The First School of Clinical Medicine Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Gastroenterology and Hepatology Guangdong Provincial People’s HospitalGuangzhou 510080Guangdong ProvinceChina

Per-oral endoscopic myotomy(POEM)is an innovative minimally invasive technique and has emerged as the preferred modality for treating achalasia and spastic esophageal disorders in numerous specialized centers *** reflux(GER)is a common complication following POEM ***,an article in the World Journal of Gastroenterology,providing a comprehensive update on post-POEM *** this article,the authors present novel insights and strategies that offer valuable implications for endoscopy.

关键词： Per-oral endoscopic myotomy Gastroesophageal reflux Progress Treatment Update

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Low-carbon development policies and achievements in the context of the livestock sector in China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 367-380页

作者： sha wei Junming FAN Yanfeng TIAN Hongmin DONG Institute of Environmental and Sustainable Development in Agriculture Chinese Academy of Agriculture SciencesBeijing 100081China Inner Mongolia YouRan Dairy Co. Ltd.Hohhot 010070China

Rapid growth and a vast transition of Chinese livestock industry driven by economic incentives make it become an important contributor on climate change over the last four *** study first analyzes the evolving lowcarbon livestock development policies and regulations,then an assessment and explanations of the achievements and non-achievements are *** findings reveal that China began to pay attention to low-carbon development policy starting in the early ***,only after the cyclic and green concept became the main sustainable development policy,China began to move seriously toward low-carbon livestock *** policy instruments were introduced,including moderate scale,feed optimization,manure resource utilization,facility and equipment allocation rate,energy conservation and ***,achievements were made in introducing such ***,due to the large share of standard agriculture and regional resources,and environmental diversity,such policies may have little effect in *** divergence between the policies and actual practices are explained,and important policies applicable to all developing countries are also recommended.

关键词： Low carbon livestock development policy recommendations divergence carbon market

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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2479-2505页

作者： Mingzhe Huang Mi Xiao Liang Gao Mian Zhou wei sha Jinhao Zhang State Key Lab of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight *** this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is *** method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell *** geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational *** topological configurations of thin-shell structures are described by constructing the effective density field on the *** volume constraints are imposed in the proximity of each control point to obtain bone-like cellular *** facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global *** numerical examples are provided to demonstrate the effectiveness of the proposed *** simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness.

关键词： Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells

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Laser powder bed fusion of NiTiFe shape memory alloy via premixed powder:microstructural evolution,mechanical and functional properties

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Rare Metals 2024年第5期43卷 2300-2316页

作者： Bo Yuan Jin-Guo Ge Liang Zhang Hong-Jun Chen Long-sha wei Yu-Duo Zhou Run-Hua Song Institute of Intelligent Manufacturing Technology Shenzhen PolytechnicShenzhen 518055China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China Guangdong Advanced Polymer Composite Engineering Technology Research Center Shenzhen Academy of Aerospace TechnologyShenzhen 518057China Jihua Laboratory Testing Center Jihua LaboratoryFoshan 528000China

High-cost pre-alloyed powder is the bottleneck problem that limits the widespread application of additivemanufactured shape memory *** this work,the lowcost ternary NiTiFe shape memory alloy is fabricated by laser powder bed fusion(LPBF)technique via mechanically mixed pre-alloy NiTi powder and varying contents pure Fe powder(1,2,3 wt%).All NiTiFe alloys show a relative density of up to 99.8%by optimizing the LPBF processing *** to the heterogeneous nucleation effect of micron-sized Fe particles,both grain refinement and texture weakening are generated in the NiTiFe alloys,accompanied by the reduction of dislocation *** the room-temperature mechanical properties,the NiTi-3Fe alloy shows the highest microhardness of HV370,but the fracture strength and elongation reduce to1701 MPa and 23%*** evolution of mechanical properties is attributed to the high internal defects,low dislocation density and the incoherent ***,the NiTi-3Fe alloy shows the quasi-linear superelasticity behavior;the superelastic recoverable strain of NiTi-1Fe and NiTi-2Fe decreased with the increase in Fe *** study provided a new-fangled insight for the development of multi-component NiTi-based shape memory alloys by additive manufacturing.

关键词： Additive manufacturing shape memory alloy Metal matrix composite Microstructure Mechanical properties

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PAN-TB治疗策略的实施对结核病防控的意义及挑战

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中国防痨杂志 2024年第10期46卷 1188-1192页

作者：沙巍同济大学附属上海市肺科医院结核病临床研究中心上海200433

全球耐药结核病的防控仍面临巨大挑战,PAN-TB方案是适用于所有结核病的一线方案,即确诊活动性结核病后即启动该方案,而不需要获得患者的耐药情况。推行PAN-TB方案的目的是旨在尽快启动有效治疗,降低传播,并可以大幅度减轻结核病规划管... 详细信息

全球耐药结核病的防控仍面临巨大挑战,PAN-TB方案是适用于所有结核病的一线方案,即确诊活动性结核病后即启动该方案,而不需要获得患者的耐药情况。推行PAN-TB方案的目的是旨在尽快启动有效治疗,降低传播,并可以大幅度减轻结核病规划管理的复杂性。它不仅是临床治疗方法,更是公共卫生手段。本文就PAN-TB策略的定义、方案的要求、全球的研究进展,以及对于结核病防控的意义和目前面临的挑战进行阐述,以期为中国结核病的防控提供新的思路。

关键词：结核抗结核药治疗应用方案评价

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Nasal congestion caused by long-term retention of a nasal foreign body near the orbit:A case report

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World Journal of Clinical Cases 2024年第20期12卷 4331-4336页

作者： Dan Wang Qing Liu Hui Liu Jia-sha wei Department of Rhinology Zibo Central HospitalZibo 255000Shandong ProvinceChina

BACKGROUND Nasal trauma presents a risk of foreign body invasion into the nasal ***,in the early treatment stage of nasal trauma,patients and doctors are not always aware of possible foreign body invasion,resulting in delayed *** describe the case of an adult patient admitted to the hospital due to left nasal congestion accompanied by yellow,purulent,and bloody *** SUMMARY Consultation with the patient revealed a history of nasal trauma 30 years prior that did not receive thorough examinations and imaging during treatment,resulting in a glass fragment retained in the nasal cavity adjacent to the *** admission,computerized tomography(CT)confirmed the presence of the foreign body in the patient’s left nasal–maxillary *** nasal foreign body led to symptoms such as chronic sinusitis,nasal polyps,fungal infection,and deviated nasal *** foreign body was successfully removed by nasal endoscopy,polypectomy,sinus fungal removal,left middle turbinate conchoplasty,fenestration via the right inferior meatus,nasal endoscopic maxillary sinus cystectomy,and *** operation was successful and without any *** CT scans should be performed in addition to necessary debridement sutures to avoid possible foreign body invasion during nasal *** planning should be tailored to the patient’s specific *** surgical method should be carefully selected,and sufficient preparation should be undertaken before the surgery to avoid possible displacement of the nasal foreign body.

关键词： Nasal foreign body Nasal endoscopic surgery Adult patients Nasal trauma Case report

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考虑局部过热约束的自支撑结构等几何拓扑优化

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机械工程学报 2024年第11期60卷 41-52页

作者：宗子凯肖蜜周冕沙伟高亮华中科技大学智能制造装备与技术全国重点实验室武汉430074 华中科技大学国家智能设计与数控技术创新中心武汉430074

等几何拓扑优化方法实现结构几何、分析和优化模型的统一,在结构优化领域具有重要的应用潜力。拓扑优化设计的结构构型复杂,通常需要采用增材制造加工成型。为确保结构的可制造性,其必须满足特定的工艺条件,因此,在优化设计阶段考虑制... 详细信息

等几何拓扑优化方法实现结构几何、分析和优化模型的统一,在结构优化领域具有重要的应用潜力。拓扑优化设计的结构构型复杂,通常需要采用增材制造加工成型。为确保结构的可制造性,其必须满足特定的工艺条件,因此,在优化设计阶段考虑制造工艺约束显得尤为重要。针对金属增材制造中常见的局部过热现象和悬垂角要求,提出一种约束局部过热的自支撑结构等几何拓扑优化方法。采用基于等几何分析的变密度法,引入可打印密度的概念,将不满足打印要求的单元过滤,实现结构自支撑;采用稳态热过程模拟模型近似评估结构的局部过热程度,并将其引入等几何拓扑优化模型中加以约束。数值算例和仿真结果表明,相比于传统等几何拓扑优化方法和仅考虑自支撑特性的等几何拓扑优化方法,该方法设计的结构在满足自支撑特性的基础上,能有效缓解增材制造中结构的局部过热现象,从而减小结构的热变形,提高尺寸精度。

关键词：等几何拓扑优化悬垂角约束局部过热约束增材制造

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来宾市主要河流和重要水库水资源现状分析

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广西水利水电 2024年第1期 58-63页

作者：韦莎来宾水文中心广西来宾546117

为了解来宾市3条主要河流及重要水库的水资源现状,通过对红水河、柳江和黔江及重要水库等分别进行水质水量监测评价和营养化评价,对主要河流重要断面的生态流量作出达标判定,同时结合大藤峡水利枢纽蓄水库区的水生态藻类检测结果进行分... 详细信息

为了解来宾市3条主要河流及重要水库的水资源现状,通过对红水河、柳江和黔江及重要水库等分别进行水质水量监测评价和营养化评价,对主要河流重要断面的生态流量作出达标判定,同时结合大藤峡水利枢纽蓄水库区的水生态藻类检测结果进行分析。结果显示,来宾市主要河流及重要水库的水资源状况较好,建议进一步采取有针对性的措施更好维护来宾水环境健康发展。

关键词：水库河流水资源营养化分析评价来宾市

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电磁学中的格林函数

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物理 2024年第1期53卷 43-49页

作者：沙威应磊肖高标浙江大学信息与电子工程学院杭州310027 浙江大学物理学院杭州310027 上海交通大学电子信息与电气工程学院上海200240

文章回顾了电磁学中的格林函数理论与格林函数方法。首先,引入标量波动方程对应的格林函数,并与信号系统中的冲击响应函数作类比。其次,引入矢量波动方程对应的并矢格林函数,包括均匀和非均匀介质中的格林函数,并探讨其与电磁理论中的... 详细信息

文章回顾了电磁学中的格林函数理论与格林函数方法。首先,引入标量波动方程对应的格林函数,并与信号系统中的冲击响应函数作类比。其次,引入矢量波动方程对应的并矢格林函数,包括均匀和非均匀介质中的格林函数,并探讨其与电磁理论中的互易定理、等效原理之间的联系。最后,介绍了考虑介质的运动效应和电磁场的量子效应下的格林函数理论。此外,文章也探讨了电磁格林函数在无线通信、电磁兼容等工程领域的应用。

关键词：格林函数介质电磁场运动效应量子效应无线通信电磁兼容

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