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Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification

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工程与科学中的计算机建模(英文) 2024年第1期138卷 201-220页

作者： Xiaoyu Zhang huizhong Zeng Shaohui Zhang Yan Zhang Mi Xiao Liping Liu Hao Zhou Hongyou Chai Liang gao Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures Beijing Institute of TechnologyBeijing100081China Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System EngineeringChina Academy of Space TechnologyBeijing100094China Key Laboratory of Metallurgical Equipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts.

关键词： Thin-walled structure lattice infill supporting component selective laser melting satellite

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Feature Extraction and Recognition for Rolling Element Bearing Fault Utilizing Short-Time Fourier Transform and Non-negative Matrix Factorization

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 96-105页

作者： gao huizhong LIANG Lin CHEN Xiaoguang XU Guanghua School of Mechanical Engineering Xi'an Jiaotong University The 705 Research Institute China Shipbuilding Industry Corporation Key Laboratory for Modern Design and Rotor-Bearing System of Education Ministry Xi'an Jiaotong University State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University

Due to the non-stationary characteristics of vibration signals acquired from rolling element bearing fault, thc time-frequency analysis is often applied to describe the local information of these unstable signals smartly. However, it is difficult to classitythe high dimensional feature matrix directly because of too large dimensions for many classifiers. This paper combines the concepts of time-frequency distribution（TFD） with non-negative matrix factorization（NMF）, and proposes a novel TFD matrix factorization method to enhance representation and identification of bearing fault. Throughout this method, the TFD of a vibration signal is firstly accomplished to describe the localized faults with short-time Fourier transform（STFT）. Then, the supervised NMF mapping is adopted to extract the fault features from TFD. Meanwhile, the fault samples can be clustered and recognized automatically by using the clustering property of NMF. The proposed method takes advantages of the NMF in the parts-based representation and the adaptive clustering. The localized fault features of interest can be extracted as well. To evaluate the performance of the proposed method, the 9 kinds of the bearing fault on a test bench is performed. The proposed method can effectively identify the fault severity and different fault types. Moreover, in comparison with the artificial neural network（ANN）, NMF yields 99.3% mean accuracy which is much superior to ANN. This research presents a simple and practical resolution for the fault diagnosis problem of rolling element bearing in high dimensional feature space.

关键词： time-frequency distribution non-negative matrix factorization rolling element bearing feature extraction

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基于低成本终端抗差速度约束差分定位算法

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大地测量与地球动力学 2024年第1期44卷 27-34页

作者：苑晓峥徐爱功高猛祝会忠辽宁工程技术大学测绘与地理科学学院辽宁省阜新市123000

受限于低成本信号接收与处理单元,低成本终端的单点定位和相对定位的精度无法得到保障。基于此,提出一种附加多普勒观测值的抗差速度约束RTD模型与RTK自适应切换模型,使用多普勒测速约束位置解,充分发挥多频信号的抗多路径能力,有效平... 详细信息

受限于低成本信号接收与处理单元,低成本终端的单点定位和相对定位的精度无法得到保障。基于此,提出一种附加多普勒观测值的抗差速度约束RTD模型与RTK自适应切换模型,使用多普勒测速约束位置解,充分发挥多频信号的抗多路径能力,有效平滑伪距噪声,保证定位精度及其稳定性;通过RTD/RTK自适应切换的方式,保证复杂观测条件下获得稳定的定位精度。基于小米8和M8终端实测定位结果表明,静态RTD模式下两种终端在东、北、高程方向的精度均优于1.5 m;动态无遮挡/部分遮挡RTD实验中,小米8终端平面精度提升54%/44%,M8终端平面精度提升51%/26%;动态车载RTK模式下M8终端东、北方向精度均优于0.5 m,模糊度固定率提升近30个百分点。

关键词：低成本终端抗差估计多普勒差分定位模糊度固定

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Wnt信号通路在糖尿病骨质疏松中的作用及中药干预的研究进展

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中国实验方剂学杂志 2024年第9期30卷 283-292页

作者：张亚奇王卫国张启栋白惠中秦灵灵高峰中日友好医院北京100029 北京中医药大学东直门医院北京100700 北京中医药大学科技处北京100029 教育部中医药防治糖尿病及其并发症创新引智基地北京100029

糖尿病骨质疏松(DOP)是糖尿病引起的一种骨骼并发症,以骨密度降低、骨微结构改变、骨质脆性升高为主要特征。DOP的进程与高糖、胰岛素抵抗、氧化应激等机制关系密切。Wnt/β-连环蛋白(β-catenin)信号通路是介导糖尿病胰岛素抵抗和骨代... 详细信息

糖尿病骨质疏松(DOP)是糖尿病引起的一种骨骼并发症,以骨密度降低、骨微结构改变、骨质脆性升高为主要特征。DOP的进程与高糖、胰岛素抵抗、氧化应激等机制关系密切。Wnt/β-连环蛋白(β-catenin)信号通路是介导糖尿病胰岛素抵抗和骨代谢平衡的重要机制,调控Wnt信号转导促进糖原合成酶激酶-3β(GSK-3β)磷酸化表达水平,可改善糖脂代谢。Wnt/β-catenin信号通路是调节骨细胞重塑的重要途径,不仅在成骨细胞和破骨细胞二者平衡中发挥重要调节作用,可以改善骨代谢平衡;并且调控Wnt通路还促进骨桥蛋白、骨钙素、Ⅰ型胶原蛋白的表达,改善骨增殖和成骨分化。近年来中医药在DOP的防治中的研究逐渐增多,中药干预Wnt通路转导改善DOP的探索取得了一定的进展。该文搜集国内外近10年来Wnt信号通路在糖代谢、骨代谢和DOP的研究,以及关于中药复方(经典方和其他)、单味中药、中药单体基于Wnt通路干预DOP的相关文献进行整理综述,以期为临床防治DOP新药的开发提供参考和方向。

关键词：糖尿病骨质疏松症 Wnt信号通路中药机制研究进展

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顾及衰减系数时空变化的全球PWV垂直改正模型

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测绘学报 2024年第5期53卷 889-899页

作者：蒋春华高祥王帅民祝会忠陈少妮刘广盛辽宁工程技术大学测绘与地理科学学院辽宁阜新123000 地理信息工程国家重点实验室陕西西安710054 中国科学院精密测量科学与技术创新研究院大地测量与地球动力学国家重点实验室湖北武汉430077 河北工程大学矿业与测绘工程学院河北邯郸056038

大气可降水量(precipitable water vapor,PWV)在多尺度气候变化及大气物理过程中扮演着重要的角色。为提高PWV垂直改正精度进一步扩展各类PWV产品的空间应用性,本文基于2010—2019年ERA5再分析资料构建了一种顾及PWV垂直衰减系数时空变... 详细信息

大气可降水量(precipitable water vapor,PWV)在多尺度气候变化及大气物理过程中扮演着重要的角色。为提高PWV垂直改正精度进一步扩展各类PWV产品的空间应用性,本文基于2010—2019年ERA5再分析资料构建了一种顾及PWV垂直衰减系数时空变化的全球适用范围的分层格网模型(GPWVCS)。同时联合2020年ERA5及无线电探空PWV,评估了本文模型在全球范围内的精度及适用性。结果表明,相比于经验模型及未分层的GPWVC模型,GPWVCS模型有效提升了PWV的垂直改正精度。以ERA5 PWV为参考,全球范围内GPWVCS模型修正PWV的RMS不超过1.9 mm。以探空数据为参考,GPWVCS模型在热带、温带、寒带及全球范围的年均RMS分别为2.24、1.29、0.44、1.44 mm,较经验模型分别提升34.6%、14.1%、10.9%及21.4%,较GPWVC模型分别提升6.4%、5.8%、9.4%及6.0%。GPWVCS的分层算法最大限度地削弱了PWV指数外推的误差累积影响,本文开发的水平分辨率为1°×1°、2°×2°及5°×5°的模型均能够显著提升全球范围内多种高差下PWV的垂直改正效果,用户可以根据计算效率及精度需求自行选择最佳模型。

关键词： GPWVCS模型大气可降水量衰减系数垂直分层

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Metal oxyacid salts-confined pyrolysis towards hierarchical porous metal oxide@carbon(MO@C)composites as lithium-ion battery anodes

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Nano Research 2023年第5期16卷 6903-6913页

作者： huizhong Xu Chang gao Zhaoyang Cheng Linghui Kong Wei Li Xiaochen Dong Jianjian Lin Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science Ministry of Education(MOE)Shandong Key Laboratory of Biochemical AnalysisCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Engineering Research Center of High Performance Polymer and Molding Technology Ministry of EducationQingdao University of Science and TechnologyQingdao 266042China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing211800China

Transition metal oxides(TMOs)have been thought of potential anodic materials for lithium-ion batteries(LIBs)owing to their intriguing properties.However,the limited conductivity and drastic volume change still hinder their practical applications.Herein,a metal oxyacid salts-confined pyrolysis strategy is proposed to construct hierarchical porous metal oxide@carbon(MO@C,MO=MoO_(2),V_(2)O_(5),WO_(3))composites for solving the aforementioned problems.A water-evaporation-induced self-assembly mechanism has been put forward for fabricating the MO@polyvinyl pyrrolidone(PVP)@SiO_(2)precursors.After the following pyrolysis and etching process,small MO nanoparticles can be successfully encapsulated in the hierarchical porous carbon framework.Profiting from the synergistic effect of MO nanoparticles and highly conductive carbon framework,MO@C composites show excellent electrochemical properties.For example,the as-obtained MoO_(2)@C composite exhibits a large discharge capacity(1513.7 mAh·g^(−1)at 0.1 A·g^(−1)),good rate ability(443.5 mAh·g^(−1)at 5.0 A·g^(−1)),supernal long-lived stability(669.1 mAh·g^(−1)after 1000 cycles at 1.0 A·g^(−1)).This work will inspire the design of novel anode materials for high-performance LIBs.

关键词： transition metal oxides hierarchical porous carbon framework anode materials lithium storage performance

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深调背景下抽真空系统改造的必要性探究

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科学技术创新 2024年第7期 51-54页

作者：王军高世杰吝江李燕平白会忠河北蔚州能源综合开发有限公司河北张家口大唐华北电力试验研究院北京

为了解决抽真空系统在运行中存在的真空泄漏率过大,对系统整体运行性能产生影响的问题,有必要进行深入的背景调查,并开展抽真空系统改造的必要性探究。从硬件方面来看,对凝汽器结构和抽气设备结构进行改造,以提高系统的性能。从软件方... 详细信息

为了解决抽真空系统在运行中存在的真空泄漏率过大,对系统整体运行性能产生影响的问题,有必要进行深入的背景调查,并开展抽真空系统改造的必要性探究。从硬件方面来看,对凝汽器结构和抽气设备结构进行改造,以提高系统的性能。从软件方面来看,通过分析漏气量对凝汽器的影响,并实现优化,以及对泵吸气性能进行修正,以提高系统的性能。通过对改造后的系统运行性能进行分析,可以得出结论:改造后的系统真空泄漏率显著降低,改造方案具备较高必要性。

关键词：深调抽真空系统改造必要性

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勃姆石/石墨烯纳米复合材料的制备及制备过程安全评价

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化工管理 2024年第14期 134-137页

作者：潘慧莹刘会中李自明李蕊张金珠高新阁辽沈工业集团有限公司辽宁沈阳110045

文章基于水热法将纳米羟基氧化铝(AlOOH)和三维石墨烯(rGO)组装成勃姆石/石墨烯纳米复合材料(AlOOH/rGO),通过XRD、Raman、FI-IR、SEM表征手段对三维石墨烯/勃姆石纳米复合材料进行表征,并通过安全检查表方法对制备过程进行安全评价。... 详细信息

文章基于水热法将纳米羟基氧化铝(AlOOH)和三维石墨烯(rGO)组装成勃姆石/石墨烯纳米复合材料(AlOOH/rGO),通过XRD、Raman、FI-IR、SEM表征手段对三维石墨烯/勃姆石纳米复合材料进行表征,并通过安全检查表方法对制备过程进行安全评价。结果表明,成功制备出AlOOH/rGO,并通过安全检查表检查发现实验室现场环境、实验操作过程及实验仪器维护保养三方面存在安全隐患,并提出了相应的安全措施,以确保实验过程的顺利进行和实验人员的安全。

关键词：三维石墨烯勃姆石复合材料安全评价

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Variation of airborne quartz in air of Beijing during the Asia-Pacific Economic Cooperation Economic Leaders' Meeting

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Journal of Environmental Sciences 2016年第1期28卷 62-68页

作者： Gang Li Yingming Li Hongxing Zhang Honghua Li Guanjun gao Qian Zhou Yuan gao Wenjuan Li huizhong Sun Xiaoke Wang Qinghua Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing Urban Ecosystem Research Station Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Environment and Health Jianghan University

Quartz particles are a toxic component of airborne paniculate matter（PM）.Quartz concentrations were analyzed by X-ray diffraction in eighty-seven airborne PM samples collected from three locations in Beijing before,during,and after the Asia-Pacific Economic Cooperation（APEC） Leaders＇ Meeting in 2014.The results showed that the mean concentrations of quartz in PM samples from the two urban sites were considerably higher than those from the rural site.The quartz concentrations in samples collected after the APEC meeting,when the pollution restriction lever was lifted,were higher than those in the samples collected before or during the APEC meeting.The quartz concentrations ranged from 0.97 to 13.2 μg/m^3,which were among the highest values amid those reported from other countries.The highest quartz concentration exceeded the Californian Office of Environmental Health Hazard Assessment reference exposure level and was close to the occupational threshold limit values for occupational settings.Moreover,a correlation analysis showed that quartz concentrations were positively correlated with concentrations of pollution parameters PM10,PM2.5,SO2 and NOx,but were negatively correlated with O3 concentration.The results suggest that the airborne quartz particles may potentially pose health risks to the general population of Beijing.

关键词： Air pollution Carcinogen Haze PM10 Quartz

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Identification and functional analysis of shared gene signatures between systemic lupus erythematosus and Sjogren's syndrome

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Rheumatology & Autoimmunity 2022年第3期2卷 150-158页

作者： Zhaowei gao Lan Yang Chong Liu Xi Wang huizhong Zhang Ke Dong Department of Clinical Laboratory Tangdu HospitalAir Force Medical UniversityXi'anShaanxiChina

Background:Systemic lupus erythematosus(SLE)is an autoimmune disease that can affect multiple systems.Sjogren's syndrome(SS)is an autoimmune disease that may be primary SS(pSS)or occur together with other autoimmune diseases,including SLE.This study aimed to explore the shared gene signatures in SLE and pSS.Methods:Gene expression data sets of SLE(GSE50772 and GSE81622)and pSS(GSE84844 and GSE48378)were obtained and analyzed for differentially expressed genes(DEGs)in peripheral blood mononuclear cells(PBMCs).A protein–protein interaction(PPI)network was constructed.Gene ontology(GO)and KEGG pathway enrichment analysis were carried out for the DEGs.Results:We screened 232 and 110 DEGs from the SLE and pSS data sets,respectively.We found 32 shared DEGs,which were all upregulated in patients compared with controls.Among these 32 DEGs,11 genes showed a more than twofold change in all data sets(IFI27,IFI44L,RSAD2,IFIT1,IFI44,USP18,IFI6,HERC5,EPSTI1,OAS1,and OAS3).PPI analysis showed that 29 genes interacted with each other.GO analysis showed that these 32 shared DEGs were mainly enriched in biological processes associated with the type Ⅰ interferon signaling pathway,defense response to viruses,response to viruses,negative regulation of viral genome replication,and the immune response.Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that these 32 DEGs were related to virus infection.Conclusion:This study showed that alterations to biological processes associated with the response to virus infection play critical roles in both SLE and pSS.

关键词： differentially expressed genes functional analysis Sjögren's syndrome systemic lupus erythematosus

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