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RISK FACTORS OF CARDIOVASCULAR DISEASES IN BEIJING

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中华医学杂志(英文版) 1988年第12期101卷 905-905页

作者： Yao Chong-hua Wu zhao-su hong zhao-guang Xu Xiao-ming Zhang Min Wu Yan-yuan Yu Shu-e Wu Ying-kai DepartmentofEpidemiologyandPreventionandDepartmentofCommunityHealth BeijingHeart LungandBloodVesselMedicalCenterandAnzhenHospital Beijing

The task of the Sino-Monica-Beijing study is to monitor the trend and determinants of cardiovascular diseases in the People's Republic of China from 1984 to 1993 as a part of the WHO Monica Project. Risk factors were studied. A total of 1 673 individuals were surveyed in 1984-85, with a response rate of 88%. The mean total serum cholesterol was 160.5mg/dl in males and 162.8mg/dl in females aged 25-64 years. The prevalence rate of established hypertension was 20.60% in males and 15.3% in females. The smoking rate was 59% in men and 14% in women. The average value of weight/height index was 23.2 in men, and 23.9 in women.

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基于混合ANN-Petri网的过程控制建模

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系统仿真学报 2001年第Z1期13卷 45-47页

作者：李宏光赵立雄北京化工大学信息科学与技术学院北京100029

针对混有离散事件的连续化工过程,提出了基于混合ANN-Petri网的控制建模方法。采用神经网络与Petri网的有效结合,较好地描述了化工过程连续和离散的混杂特性,并以某化工蒸发过程为例,进行了详细的讨论和分析,建立了混杂过程的控制模型,... 详细信息

针对混有离散事件的连续化工过程,提出了基于混合ANN-Petri网的控制建模方法。采用神经网络与Petri网的有效结合,较好地描述了化工过程连续和离散的混杂特性,并以某化工蒸发过程为例,进行了详细的讨论和分析,建立了混杂过程的控制模型,并且给出了仿真结果。

关键词：混杂过程混合Petri网人工神经元网络建模控制

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基于无迹卡尔曼滤波的室内超宽带跟踪算法

轻工学报 2017年第1期32卷 82-88页

作者：杨倩王洋赵红梅崔光照郑州轻工业学院电气信息工程学院河南郑州450002

为解决移动目标在室内跟踪定位误差较大的问题,提出了一种基于无迹卡尔曼滤波(UKF)的超宽带(UWB)跟踪定位算法.该算法在定位阶段联合到达时间(TOA)与接收信号强度(RSS)两种定位算法的优势以获得较高的定位精度;在跟踪阶段,将TOA-RSS联... 详细信息

为解决移动目标在室内跟踪定位误差较大的问题,提出了一种基于无迹卡尔曼滤波(UKF)的超宽带(UWB)跟踪定位算法.该算法在定位阶段联合到达时间(TOA)与接收信号强度(RSS)两种定位算法的优势以获得较高的定位精度;在跟踪阶段,将TOA-RSS联合定位算法获得的量测值进行UKF估计,以得到移动目标的跟踪轨迹.仿真结果表明,该算法室内滤波误差与均方根误差均比同样使用TOA-RSS定位方法而采用扩展卡尔曼滤波(EKF)估计算法有一定程度的降低,跟踪定位精度有较大提高.

关键词：超宽带目标跟踪无迹卡尔曼滤波扩展卡尔曼滤波 TOA-RSS

An analysis in metal barcode label design for reference

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Frontiers of Information Technology & Electronic Engineering 2016年第2期17卷 173-184页

作者： Yin zhao hong-guang XU Qin-yu ZHANG Communication Engineering Research Center Harbin Institute of Technology Shenzhen Graduate School

We employ nondestructive evaluation involving AC field measurement in detecting and identifying metal barcode labels,providing a reference for *** the magnetic scalar potential boundary condition at notches in thin-skin field theory and 2D Fourier transform,we introduce an analytical model for the magnetic scalar potential induced by the interaction of a high-frequency inducer with a metal barcode label containing multiple narrow saw-cut notches,and then calculate the magnetic field in the free space above the metal barcode *** the simulations of the magnetic field,qualitative analysis is given for the effects on detecting and identifying metal barcode labels,which are caused by metal material,notch characteristics,exciting inducer properties,and other factors that can be used in metal barcode label design as *** results are in good accordance with experiment results.

关键词： Metal barcode label Signal detection AC field measurement Internet of things

Altered 3D genome reorganization mediates precocious myeloid differentiation of aged hematopoietic stem cells in inflammation

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Science China Life Sciences 2025年

作者： Xinyu Cui Yu Dong Qiang Zhan Yixin Huang Qianshu Zhu Zihao Zhang guang Yang Liping Wang Shijun Shen Jia zhao Zhiyi Lin Jiatong Sun Zhongqu Su Yihan Xiao Chuyu Zhang Yuwei Liang Lu Shen Lichen Ji Xuguang Zhang Jiqing Yin hong Wang Zhiyang Chen Zhenyu Ju Cizhong Jiang Rongrong Le Shaorong Gao Clinical and Translational Research Center of Shanghai First Maternity & Infant Hospital Frontier Science Center for Stem Cells School of Life Sciences and Technology Tongji University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education Orthopaedic Department of Tongji Hospital School of Life Sciences and Technology Tongji University Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative Medicine Department of Developmental & Regenerative Medicine College of Life Science and Technology Jinan University Shandong Key Laboratory of Animal Bioengineering and Disease Prevention College of Animal Science and Technology Shandong Agricultural University Department of Joint Surgery Shanghai East Hospital Tongji University School of Medicine Shanghai Institute of Nutrition and Health Chinese Academy of Sciences

Inflammation is a driving force of hematopoietic stem cells(HSCs) aging, causing irreversible exhaustion of functional HSCs. However, the underlying mechanism of HSCs erosion by inflammatory insult remains poorly understood. Here, we find that transient LPS exposure primes aged HSCs to undergo accelerated differentiation at the expense of self-renewal, leading to depletion of HSCs. Meanwhile, the central regulator nuclear factor kappa B(NF-κB) mediating functional impairment by inflammation insult induces differential transcriptional response in aged HSCs compared with young HSCs, with precocious activation of myeloid lineage genes. Altered compartmentalization and chromatin loop formation are associated with aging-related differential transcriptional response in HSCs upon lipopolysaccharide(LPS)stimulation. Mechanistically, enhancer and promoter regions of myeloid lineage genes in aged HSCs are more accessible and display more rapid and prominent CTCF occupancy upon LPS stimulation. Our study provides comprehensive resources for the three-dimensional(3D)genome structure of HSCs and sheds light into the ordered genome organization and the associated transcriptome signature underlying HSCs aging.

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分布式水文模型亚流域合理划分水平刍议

水土保持学报 2003年第4期17卷 75-78页

作者：郝芳华张雪松程红光赵卫民刘虹北京师范大学环境科学研究所水环境模拟国家重点实验室北京100875 黄河水利委员会水文局兰州730030

不同的亚流域划分对流域径流和泥沙负荷模拟的影响源于地形、土壤、土地利用以及气候特征输入的空间分布不均匀性。假设当亚流域划分充分考虑流域输入数据空间分布不均匀性时,流域模拟的输出结果趋于稳定,并应用分布式水文模型——SWAT... 详细信息

不同的亚流域划分对流域径流和泥沙负荷模拟的影响源于地形、土壤、土地利用以及气候特征输入的空间分布不均匀性。假设当亚流域划分充分考虑流域输入数据空间分布不均匀性时,流域模拟的输出结果趋于稳定,并应用分布式水文模型——SWAT作为研究工具,在GIS技术支持下,选择两个面积不同的流域采用不同的亚流域划分数量进行流域径流和泥沙负荷模拟。模拟结果表明,当亚流域划分数量达到一定水平时,增加亚流域划分对模型输出结果的影响较小,这在一定程度上证实了上述假设。在此基础上,以简化模型输入数据和输出结果分析处理工作且保证模拟精度为原则,对分布式水文模型亚流域划分的合理划分水平进行了探讨。

关键词：分布式水文模型亚流域划分 SWAT 流域径流泥沙负荷模拟精度

Quantifying spectral thermal transport properties in framework of molecular dynamics simulations:a comprehensive review

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Rare Metals 2023年第12期42卷 3914-3944页

作者： Yi-Xin Xu hong-zhao Fan Yan-guang Zhou Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China HKUST Shenzhen-hong Kong Collaborative Innovation Research Institute Shenzhen 518000China

Over the past few decades,significant progress has been made in micro-and nanoscale heat *** computational methods have been developed to quantitatively characterize the thermal transport in bulk materials and across the interfaces,which benefit the thermal management design in microelectronics and energy conversion in thermoelectrics *** this paper,the methods and studies on quantifying thermal transport properties using molecular dynamics simulations are comprehensively *** classical methods based on molecular dynamics simulations are first introduced,i.e.,equilibrium molecular dynamics and nonequilibrium molecular dynamics,to calculate the thermal transport properties in bulk materials and across the *** spectroscopy methods are then reviewed,which are developed in the framework of equilibrium molecular dynamics(i.e.,time domain normal mode analysis,spectral energy density,Green-Kubo modal analysis) and methods proposed based on the nonequilibrium molecular dynamics(i.e.,time domain direct decompose method,frequency domain direct decompose method and spectral heat flux method).In the subsequent section,the calculations of spectral thermal conductivities using these computational methods in various systems are presented,including simple crystals,low-dimensional materials,complex materials and *** that,spectral thermal transport across the interfacial systems is discussed,which includes solid/solid interfaces,solid/solid interfaces with interfacial engineering and solid/liquid *** fundamental challenges in molecular dynamics simulations,such as including quantum effects and quantifying the anharmonic contributions,are discussed as ***,some open problems on spectroscopy thermal transport properties in the framework of molecular dynamics simulations are given in the summary.

关键词： Thermal transport Spectral decomposition Molecular dynamics simulations Interfacial thermal transport Complex system

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基于汽车用钢碰撞性能的高应变速率测试探讨

物理测试 2016年第6期34卷 25-28页

作者：王亚芬杜洪志赵广东本钢板材股份有限公司产品研究院辽宁本溪117000 本钢板材股份有限公司制造部辽宁本溪117000

介绍了高应变速率下汽车用钢测试技术的发展历程,目前国际上使用的液压伺服高速拉伸测试系统及数据后处理模式,测试和应用过程中出现的亟待解决的问题等。研究和模拟汽车用钢在高应变速率范围的动态力学行为,对汽车轻量化发展进程中优... 详细信息

介绍了高应变速率下汽车用钢测试技术的发展历程,目前国际上使用的液压伺服高速拉伸测试系统及数据后处理模式,测试和应用过程中出现的亟待解决的问题等。研究和模拟汽车用钢在高应变速率范围的动态力学行为,对汽车轻量化发展进程中优化结构设计、合理选择材料和提高车身安全性具有重要的指导作用。

关键词：高应变速率高速拉伸试验机汽车用钢碰撞本构方程

紫外线消毒系统中超声波抑垢的机制及参数优化

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土木与环境工程学报（中英文） 2025年第1期47卷 221-228页

作者：陈光赵志伟李莉重庆大学环境与生态学院重庆400045

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结... 详细信息

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结果表明,超声波能通过延长结垢诱导期来抑制垢的生成;以相对紫外线强度为考察对象,通过单因素试验确定超声波功率、清洗周期、超声时间合适的范围分别在500~1000 W、0.5~1.0 d、20~40 min;对于使用时间为0、0.5、1、3、5 a的石英套管,超声波均有很好的抑垢效果。为了进一步优化参数,采用Box-Behnken设计法和响应面分析方法对主要因素加以优化,得到了响应面回归模型和最优解。结果表明,超声波技术抑垢清垢的优化工艺参数为超声波功率P=965 W,清洗周期T=0.5 d,超声时间t=34 min,预测相对紫外线强度最大值为1.01。通过统计学检验,模型具有良好的拟合性,在优化工艺条件下得到的相对紫外线强度预测值与试验值接近,误差为1.00%。

关键词：超声波紫外线消毒石英套管结垢响应面法

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