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Science China(Technological Sciences) 2016年第11期59卷 1746-1758页

作者： YANG Chen hou XinBin WANG Li ZHANG XingHua Qian Xuesen Laboratory of Space Technology China Academy of Space Technology

This paper presents a damage identification method that consists of a fusion sensitivity matrix that contains information on dynamic and static responses. Based on natural frequency and static displacement, the study defines and considers damage criteria such as 1D and 2D single and fusion load cases. To overcome the lack of sufficient information on damage identification in large-scale structures, the authors consider multiple responses to and objective descriptions of uncertainties and various *** to the finite element model and the structural responses described and measured, the fusion methods and damage criteria treat uncertainty as non-probability intervals. As long as we know the bounds of uncertain parameters, the intervals of the elemental stiffness parameters in undamaged and damaged models can be obtained by interval technology. Two numerical examples—a damage-criteria numerical example and a 5-span with 25-bar truss structure in a space solar power station—are proposed. Both examples indicate the veracity of the interval method.

关键词： damage identification fusion sensitivity matrix damage criteria natural frequency static displacement interval analysis space solar power station

钻井液漏斗黏度和密度自动检测仪的研制与应用

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煤田地质与勘探 2024年第3期52卷 176-183页

作者：谢辉郑立群刘福林梁梦佳刘璇蔡记华杨现禹侯继武武汉誉城千里建工有限公司湖北武汉430051 中国地质大学(武汉)工程学院湖北武汉430074

近年来,国内外对钻井液性能自动检测技术的研究取得了长足进步。针对现有钻井液自动检测仪器成本高、结构复杂和工作环境受限等问题,研制了钻井液漏斗黏度和密度自动在线检测仪。使用可编程逻辑控制器、物联网模组、压力传感器、超声传... 详细信息

近年来,国内外对钻井液性能自动检测技术的研究取得了长足进步。针对现有钻井液自动检测仪器成本高、结构复杂和工作环境受限等问题,研制了钻井液漏斗黏度和密度自动在线检测仪。使用可编程逻辑控制器、物联网模组、压力传感器、超声传感器、蠕动泥浆泵、电动球阀和隔膜泵等,搭建取浆模块、检测模块、清洗模块和控制模块,实现了对钻井液漏斗黏度和密度的自动检测、移动端设备数据查看和操作等功能。采用传感器数据融合和滤波算法等方法提高仪器精度和稳定性,对不同钻井液体系性能测试验证,漏斗黏度误差控制在±1 s,密度误差控制在±0.01 g/cm^(3),且可连续地对钻井液性能进行自动测试。室内测试和现场试验结果表明,该仪器具有操作方便、测试结果准确、可重复性高、人为测量误差小和节约人工等优点,能满足实际钻井施工过程中对钻井液性能检测的要求,具有较强的普适性和广泛的应用前景。

关键词：钻井液自动检测漏斗黏度密度

A Downward-looking Three-dimensional Imaging Method for Airborne FMCW SAR Based on Array Antennas

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Chinese Journal of Aeronautics 2011年第1期24卷 55-64页

作者： hou Haiping QU Changwen Zhou Qiang XIANG Yingchun Department of Electronic and Information Engineering Naval Aeronautical and Astronautical University Yantai 264001 China

With regard to problems in conventional synthetic aperture radar （SAR）, such as imaging distortion, beam limitation and failure in acquiring three-dimensional （3-D） information, a downward-looking 3-D imaging method based on frequency modulated continuous wave （FMCW） and digital beamforming （DBF） technology for airborne SAR is presented in this study. Downward-looking 3-D SAR signal model is established first, followed by introduction of virtual antenna optimization factor and discussion of equivalent-phase-center compensation. Then, compensation method is provided according to reside video phase （RVP） and slope term for FMCW SAR. As multiple receiving antennas are applied to downward-looking 3-D imaging SAR, range cell migration correction （RCMC） turns to be more complex, and corrective measures are proposed. In addition, DBF technology is applied in realizing cross-track resolution. Finally, to validate the proposed method, magnitude of slice, peak sidelobe ratio （PSLR）, integrated sidelobe ratio （ISLR） and two-dimensional （2-D） contour plot of impulse response function （IRF） of point target in three dimensions are demonstrated. Satisfactory performances are shown by simulation results.

关键词： synthetic aperture radar radar imaging frequency modulated continuous wave downward-looking three-dimensional array antenna digital beamforming

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双目中子散射相机快速定位方法研究

哈尔滨工程大学学报 2024年第8期45卷 1632-1638页

作者：侯英伟宋玉收吴冬冬刘鲁涛周志波武朝辉哈尔滨工程大学核科学与技术学院黑龙江哈尔滨150001 哈尔滨工程大学信息与通信工程学院黑龙江哈尔滨150001 国家核安保技术中心北京102401

为了探究使用中子散射成像法对核材料的定位分辨率和测距精度与源项方位之间的关系,以及提高定位性能的可行方案,本文利用Geant4软件模拟了位于不同方位的Cf-252中子源成像过程。使用交点反投影成像法与双目视觉测距法进行二维成像与测... 详细信息

为了探究使用中子散射成像法对核材料的定位分辨率和测距精度与源项方位之间的关系,以及提高定位性能的可行方案,本文利用Geant4软件模拟了位于不同方位的Cf-252中子源成像过程。使用交点反投影成像法与双目视觉测距法进行二维成像与测距,研究了定位误差与中子源方位之间的依赖性。研究表明:源项位置距离成像平面中心越远,成像效果越差,当改变探测系统布置时可能出现定位死区,并且通使探测器面向源项所在方向会增强成像性能。本文提出的快速定位未知位置中子源或核材料的方法及探测器布置方案有效。

关键词：中子散射成像交点反投影成像双目视觉测距核材料定位蒙特卡罗模拟快速定位液闪探测器双目对焦

枞酸在顺铂耐药鼻咽癌细胞增殖、侵袭、迁移中的作用及分子机制

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临床耳鼻咽喉头颈外科杂志 2024年第3期38卷 188-194,199页

作者：袁艳艳蓝苑钊崔毅侯明华唐金勇文浩杰郴州市第一人民医院耳鼻咽喉头颈外科湖南郴州423000 南方医科大学第一临床学院

目的探讨枞酸在顺铂耐药鼻咽癌细胞增殖、侵袭、迁移的作用及分子机制。方法①药物浓度递增法构建顺铂耐药鼻咽癌C666/DDP细胞株。②枞酸对C666/DDP细胞增殖、侵袭及迁移的影响研究:CCK-8法、活性氧(ROS)及线粒体膜电位(MMP)水平检测及... 详细信息

目的探讨枞酸在顺铂耐药鼻咽癌细胞增殖、侵袭、迁移的作用及分子机制。方法①药物浓度递增法构建顺铂耐药鼻咽癌C666/DDP细胞株。②枞酸对C666/DDP细胞增殖、侵袭及迁移的影响研究:CCK-8法、活性氧(ROS)及线粒体膜电位(MMP)水平检测及裸鼠皮下成瘤实验检测枞酸对C666/DDP细胞体外、体内增殖及凋亡能力的影响;Transwell法检测细胞侵袭和迁移能力。③Western blot及IHC法检测PI3K/AKT/mTOR通路相关蛋白的表达情况。结果①顺铂对C666-1细胞毒性IC50约为25μmol/L。RI=25μmol/L/4μmol/L=6.25,获得耐药性,C666-1-DDP耐药株构建成功。②枞酸可促进C666/DDP细胞凋亡,抑制其增殖,且表现为G2/M期阻滞;Transwell显示枞酸抑制C666/DDP细胞迁移及侵袭能力,提高C666/DDP细胞ROS水平并使MMP降低。③动物实验显示枞酸在体内呈浓度梯度抑制顺铂耐药鼻咽癌的增殖,抑制PI3K/AKT/mTOR信号通路相关蛋白的表达。结论枞酸可抑制顺铂耐药鼻咽癌细胞增殖、侵袭及迁移,其机制与抑制PI3K/AKT/mTOR信号通路有关。

关键词：枞酸鼻咽肿瘤顺铂耐药分子机制

NaFeTiO4 nanorod/multi-walled carbon nanotubes composite as an anode material for sodium-ion batteries with high performances in both half and full cells

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Nano Research 2017年第10期10卷 3585-3595页

作者： Xuan hou Chuanchuan Li Huayun Xu Liqiang Xu Key Laboratory of Colloid & Interface Chemistry (Shandong University) Ministry of Education and School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China

NaFeTiO4 nanorods of high yields （with diameters in the range of 30-50 nm and lengths of up to 1-5 μm） were synthesized by a facile sol-gel method and were utilized as an anode material for sodium-ion batteries for the first time. The obtained NaFeTiO4 nanorods exhibit a high initial discharge capacity of 294 mA·h·g^-1 at 0.2 C （1 C = 177 mA·g^-1）, and remain at 115 mA·h·g^-1 after 50 cycles. Furthermore, multi-walled carbon nanotubes （MWCNTs） were mechanically milled with the pristine material to obtain NaFeTiO4/MWCNTs. The NaFeTiO4/MWCNTs electrode exhibits a significantly improved electrochemical performance with a stable discharge capacity of 150 mA·h·g^-1 at 0.2 C after 50 cycles, and remains at 125 mA·h·g^-1 at 0.5 C after 420 cycles. The NaFeTiO4/MWCNTs//Na3V2（PO4）3/C full cell was assembled for the first time; it displays a discharge capacity of 70 mA·h·g^-1 after 50 cycles at 0.05 C, indicating its excellent performances. X-ray photoelectron spectroscopy, ex situ X-ray diffraction, and Raman measurements were performed to investigate the initial electrochemical mechanisms of the obtained NaFeTiO4/MWCNTs.

关键词： nanorods sodium-ion batteries multi-walled carbon nanotubes full cell

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端部方锥形薄壁构件的抗撞性尺寸优化

机械强度 2007年第4期29卷 682-685页

作者：侯淑娟李青龙述尧湖南大学汽车车身先进设计制造国家重点实验室长沙410082 湖南大学力学与航空航天学院长沙410082

基于显式有限元技术,采用响应面法,以结构的比吸能为优化函数,以提高车辆吸能原件的抗撞性为目的,研究正方形截面金属薄壁构件的端部锥形尺寸对抗撞性的影响。经过数值分析,得出端部为方锥形的正方形截面薄壁构件的比吸能关于锥形长度... 详细信息

基于显式有限元技术,采用响应面法,以结构的比吸能为优化函数,以提高车辆吸能原件的抗撞性为目的,研究正方形截面金属薄壁构件的端部锥形尺寸对抗撞性的影响。经过数值分析,得出端部为方锥形的正方形截面薄壁构件的比吸能关于锥形长度和小锥边长的变化规律,这些规律可以用于实际吸能原件的设计,为进一步研究奠定基础。

关键词：优化有限元锥形薄壁构件抗撞性比吸能

Higher-order crack tip fields for functionally graded material plate with transverse shear deformation

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Applied Mathematics and Mechanics(English Edition) 2016年第6期37卷 695-706页

作者： Dianhui hou Xiao CHONG Guixiang HAO Yao DAI Institute of Command and Information Systems PLA University of Science and TechnologyNanjing 210007China Changping School of Noncommissioned Officer PLA Academy of EquipmentBeijing 102200China Army 73111 Xiamen 361025China Academy of Armored Force Engineering Beijing 100072China

The crack tip fields are investigated for a cracked functionally graded material （FGM） plate by Reissner＇s linear plate theory with the consideration of the transverse shear deformation generated by bending. The elastic modulus and Poisson＇s ratio of the functionally graded plates are assumed to vary continuously through the coordinate y, according to a linear law and a constant, respectively. The governing equations, i.e., the 6th-order partial differential equations with variable coefficients, are derived in the polar coordinate system based on Reissner＇s plate theory. Furthermore, the generalized displacements are treated in a separation-of-variable form, and the higher-order crack tip fields of the cracked FGM plate are obtained by the eigen-expansion method. It is found that the analytic solutions degenerate to the corresponding fields of the isotropic homogeneous plate with Reissner＇s effect when the in-homogeneity parameter approaches zero.

关键词： crack tip field Reissner's effect plate functionally graded material (FGM),eigen-expansion method

Virtual network embedding for power savings of servers and switches in elastic data center networks

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Science China Earth Sciences 2016年第12期59卷 97-110页

作者： Weigang hou Cunqian YU Lei GUO Xuetao WEI School of Computer Science and Engineering Northeastern University School of Information Technology University of Cincinnati

Currently, the elastic interconnection has realized the high-rate data transmission among data centers(DCs). Thus, the elastic data center network(EDCN) emerged. In EDCNs, it is essential to achieve the virtual network(VN) embedding, which includes two main components: VM(virtual machine) mapping and VL(virtual link) mapping. In VM mapping, we allocate appropriate servers to hold VMs. While for VL mapping,an optimal substrate path is determined for each virtual lightpath. For the VN embedding in EDCNs, the power efficiency is a significant concern, and some solutions were proposed through sleeping light-duty ***, the increasing communication traffic between VMs leads to a serious energy dissipation problem, since it also consumes a great amount of energy on switches even utilizing the energy-efficient optical transmission technique. In this paper, considering load balancing and power-efficient VN embedding, we formulate the problem and design a novel heuristic for EDCNs, with the objective to achieve the power savings of servers and switches. In our solution, VMs are mapped into a single DC or multiple DCs with the short distance between each other, and the servers in the same cluster or adjacent clusters are preferred to hold VMs. Such that, a large amount of servers and switches will become vacant and can go into sleep mode. Simulation results demonstrate that our method performs well in terms of power savings and load balancing. Compared with benchmarks, the improvement ratio of power efficiency is 5%–13%.

关键词： elastic data center network green virtual network embedding integrated optimization load balancing power efficiency

Abundance and community of snow bacteria from three glaciers in the Tibetan Plateau

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Journal of Environmental Sciences 2010年第9期22卷 1418-1424页

作者： Shuhong Zhang Guangli Yang Yetang Wang Shugui hou Department of Life Science Shangqiu Normal University Shangqiu 476000 China School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shandong Marine Fisheries Research Institute Yantai 264006 China

Bacterial abundance and diversity in snow of East Rongbuk, Laohugou and Halluogou glaciers on the Tibetan Plateau were investigated through epifluorescence microscope and denaturing gradient gel electrophoresis. Cell abundance ranged from 4.0 × 10^3 to 290.2 × 10^3 cells/mL. The phylogenetic trees placed the 16S rRNA sequences in four major groups： Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. Brevundimonas, Flavobacterium, Hymenobacter, Bacillus, Polaromonas, Rhodoferax and Streptomyces were widely distributed bacteria in glaciers from different cold regions. The remaining five genera of Hylemonella, Delftia, Zoogloea, Blastococcus and Rhodococcus were endemism, only recovered from our investigated glaciers. It is proposed that the three glaciers on the Tibetan Plateau provide a specific ecological niche for prolonging survival of diverse microbial lineages.

关键词： bacterial diversity glacial snow the Tibetan Plateau