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Finite-horizon resilient state estimation for complex networks with integral measurements from partial nodes

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Science China(Information Sciences) 2022年第3期65卷 167-181页

作者： Nan hou Jiahui LI Hongjian LIU Yuan GE Hongli DONG Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University Key Laboratory of Advanced Perception and Intelligent Control of High-end Equipment Ministry of EducationAnhui Polytechnic University School of Electrical Engineering Anhui Polytechnic University

This paper proposes a finite-horizon state estimation method for a kind of complex network that suffers from randomly occurring gain variations. The method involves utilizing integral measurements from a portion of nodes in such complex networks. Integral measurements are carried out to characterize time delays that occur in signal acquisition together with real-time signal processing. Measurements from only partial nodes reflect the fact that signals of several sensors are unacquirable. A Gaussian random variable is utilized to depict the random appearance of gain variations during the practical implementation of estimators. The aim of this paper is to construct finite-horizon resilient estimators for complex networks in view of integral measurements from a portion of nodes that fulfill the specified H∞ performance demand involving a specified disturbance attenuation level. Necessary and sufficient conditions are put forward to ensure that such ideal estimators exist by employing stochastic analysis as well as using the completing squares method. The gain parameters of the finite-horizon estimators are expressed by adopting the Moore-Penrose pseudoinverse and acquired through solving the solutions to a group of coupled backward recursive Riccati difference equations with constraint conditions. A confirmatory instance is carried out that demonstrates the feasibility of the newly developed estimation algorithm.

关键词： complex networks finite-horizon $H_{\infty}$ partial-nodes-based state estimation gain variations backward recursive Riccati difference equations integral measurements

The Development of a Two-finger Dexterous Bionic Hand with Three Grasping Patterns-NWAFU Hand

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Journal of Bionic Engineering 2020年第4期17卷 718-731页

作者： zhiguo Li zhongliang hou Yuxiao Mao Yan Shang Lukasz Kuta College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYangling 712100China Institute of Environmental Protection and Development Wroclaw University of Environmental and Life SciencesWroclaw 50-375Poland

Bionic inspiration from human thumb and index finger was the drive to design a high-performance two-finger dexterous *** size of each phalanx and the motion range of each joint in the human thumb and index finger were summarized,and the features of three grasping patterns were described in ***,a two-finger dexterous bionic hand with 6 Degrees of Freedom(DoFs)was *** the mechanical thumb and index finger were made up of three rigid phalanx links and three mechanical rotation *** grasp-release tests validated that the bionic hand can perform three grasping patterns:power grasp,precision pinch and lateral *** grasping success rates were high under the following cases:(1)when power grasping was used to grasp a ring with external diameter 20 mm-140 mm,a cylinder with massze and the hand manipulation dexterity.

关键词： dexterous bionic hand mechanical finger power grasp precision pinch lateral pinch

Process and challenges of stainless steel based bipolar plates for proton exchange membrane fuel cells

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International Journal of Minerals,Metallurgy and Materials 2022年第5期29卷 1099-1119页

作者： Gaoyang Liu Faguo hou Shanlong Peng Xindong Wang Baizeng Fang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Chemical and Biological Engineering University of British Columbia2360 East MallVancouverBC V6T 1Z3Canada

Proton exchange membrane fuel cell(PEMFC)powered automobiles have been recognized to be the ultimate solution to replace traditional fuel automobiles because of their advantages of PEMFCs such as no pollution,low temperature start-up,high energy density,and low *** one of the core components,the bipolar plates(BPs)play an important role in the PEMFC *** graphite BPs and composite BPs have been criticized for their shortcomings such as low strength,high brittleness,and high processing *** contrast,stainless steel BPs(SSBPs)have recently attracted much attention of domestic and foreign researchers because of their excellent comprehensive performance,low cost,and diverse options for automobile ***,the SSBPs are prone to corrosion and passivation in the PEMFC working environment,which lead to reduced output power or premature *** review is aimed to summarize the corrosion and passivation mechanisms,characterizations and evaluation,and the surface modification technologies in the current SSBPs *** non-coating and coating technical routes of SSBPs are demonstrated,such as substrate component regulation,thermal nitriding,electroplating,ion plating,chemical vapor deposition,and physical vapor deposition,*** coating materials for SSBPs are metal coatings,metal nitride coatings,conductive polymer coatings,and polymer/carbon coatings,*** the surface modification technologies can solve the corrosion resistance problem of stainless steel without affecting the contact resistance,however still facing restraints such as long-time stability,feasibility of low-cost,and mass production *** paper is believed to enrich the knowledge of high-performance and long-life BPs applied for PEMFC automobiles.

关键词： automobile application proton exchange membrane fuel cell stainless steel bipolar plates corrosion resistance contact resistance

Running coupling constant at finite chemical potential and magnetic field from holography

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Chinese Physics C 2022年第7期46卷 8-14页

作者： Xun Chen Lin zhang Defu hou School of Nuclear Science and Technology University of South China Hengyang 421001China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Central China Normal University Wuhan 430079China

According to gauge/gravity duality,we use an Einstein-Maxwell-dilaton(EMD)model to study the running coupling constant at finite chemical potential and magnetic ***,we calculate the effect of temperature on the running coupling constant and find the results are qualitatively consistent with lattice guage ***,we calculate the effect of chemical potential and magnetic field on running *** is found that the chemical potential and magnetic field both suppress the running coupling ***,the effect of the magnetic field is slightly larger than that of chemical potential for a fixed *** with the confinement phase,the magnetic field has a large influence on the running coupling in the deconfinement phase.

关键词： holographic QCD magnetic field running coupling

N末端B型利钠肽原在植入磁液悬浮左心室辅助装置终末期心衰患者中应用价值初探

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中华检验医学杂志 2024年第3期47卷 264-271页

作者：侯泽刘雨庭王欣怡叶英楠王孟薇贾克刚天津医科大学心血管病临床学院天津300457 天津大学泰达国际心血管病医院检验科天津300457

目的探讨终末期心衰(ESHF)患者在植入HeartCon型左心室辅助装置(LVAD)术前和术后N末端B型利钠肽原(NT-proBNP)的变化及对预测心脏不良事件的作用。方法回顾性研究, 连续选取2020年9月15日至2023年6月20日在泰达国际心血管病医院住院治... 详细信息

目的探讨终末期心衰(ESHF)患者在植入HeartCon型左心室辅助装置(LVAD)术前和术后N末端B型利钠肽原(NT-proBNP)的变化及对预测心脏不良事件的作用。方法回顾性研究, 连续选取2020年9月15日至2023年6月20日在泰达国际心血管病医院住院治疗植入HeartCon型LVAD的ESHF患者30例, 其中男23例, 女7例, 年龄54.5(40.8, 60.0)岁。分析其临床资料, 测量其术前水平和随访期内血液样本中NT-proBNP浓度。对患者定期随访, 记录出院后6个月内主要不良心脏事件, 包括心源性死亡和右心衰再住院;Logistic回归进行预后分析, ROC曲线评估NT-proBNP对LVAD患者不良预后的辅助诊断价值。通过对NT-proBNP诊断不良预后的临界值分成两组, 用Kaplan-Meier进行生存分析, 并用Log Rank检验;Cox回归分析随访6个月高水平NT-proBNP是否为LVAD患者不良预后的危险因素。结果成功植入HeartCon型LVAD的30例ESHF患者术前NT-proBNP中位水平达到3 251.0(1 544.5, 6 401.5)pg/ml, 在植入后第7天下降(3 251.0 比 1 815.0 pg/ml, P3 251.0 pg/ml组患者术后住院时间更长(47 d 比 33 d, z=-2.138, P=0.032)。多因素 Logistic 回归分析发现仅术后第7天NT-proBNP是LVAD患者术后预后不良的预测指标, OR值为1.001(P=0.011);ROC曲线分析术后第7天NT-proBNP水平对不良预后的辅助诊断价值(cut-off 值为2 083.0 pg/ml), AUC 为0.833(P=0.002);根据临界值分组, Kaplan-Meier 生存分析结果显示术后第7天NT-proBNP>2 083.0 pg/ml组的6个月内发生心脏不良事件时间明显短于NT-proBNP≤2 083.0 pg/ml组差异有统计学意义(3.538±0.689比5.471±0.323个月, P=0.004);Cox回归分析显示术后第7天NT-proBNP>2 083.0 pg/ml组心脏不良事件风险是NT-proBNP≤2 083.0 pg/ml组的4.25倍(HR=4.25, P=0.035)。结论 HeartCon型LVAD患者术前NT-proBNP水平越高术后住院时间越长。术后第7天NT-proBNP水平下降最明显, 术后第7天NT-proBNP水平是心脏不良事件发生的危险因子, 可作为植入LVAD的终末期心衰患者预后不良事件的预测因素。

关键词：心力衰竭左心室辅助装置终末期心力衰竭 NT-proBNP

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核电厂定位销局部干法水下TIG焊接工艺

焊接学报 2024年第2期45卷 7-12,I0003页

作者：孙清洁张清华赵永庆郭佳威李天佑班华康侯少军哈尔滨工业大学先进焊接与连接国家重点实验室哈尔滨150001 哈尔滨工业大学(威海) 特种焊接技术省重点实验室威海264209

以核电厂定位销水下焊接为研究对象,研制双层气体保护的局部干法水下TIG旋转焊枪,运动轨迹通过直流电机带动钨极绕固定直径转动实现.对核级材料z2CN19-10控氮奥氏体不锈钢进行焊接,研究局部干法水下TIG焊接焊缝成形,优化工艺参数,结合... 详细信息

以核电厂定位销水下焊接为研究对象,研制双层气体保护的局部干法水下TIG旋转焊枪,运动轨迹通过直流电机带动钨极绕固定直径转动实现.对核级材料z2CN19-10控氮奥氏体不锈钢进行焊接,研究局部干法水下TIG焊接焊缝成形,优化工艺参数,结合热循环曲线及电弧形态,分析焊接接头显微组织及力学性能.结果表明,当焊枪的内层和外层保护气均通氩气时,焊缝成形良好,电弧形态稳定;增大焊接电流或减小焊接速度均使焊缝熔深增大,熔宽增大;对比水下焊接接头和陆上焊接接头发现,水的快速冷却作用会促使熔合线附近的铁素体的形态由树枝状转变为板条状,奥氏体含量减少,焊缝中心晶粒细化;水下焊接接头的显微硬度和力学性能略高于陆上焊接接头.

关键词：水下局部干法焊接 TIG焊接控氮奥氏体不锈钢焊缝成形组织性能

2021年江苏省句容市儿童青少年甲状腺结节流行状况及影响因素分析

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中华地方病学杂志 2024年第5期43卷 376-382页

作者：赵庆华张予晗曹俊侯金花武丹江成功句容市疾病预防控制中心血寄地防科，句容212400

目的了解江苏省句容市儿童青少年碘营养状况、甲状腺结节流行状况及其分布特征,探讨儿童青少年甲状腺结节的危险因素。方法2021年采用整群抽样法在句容市城区、乡镇各抽取中、小学校1所,每所学校以班级为单位抽取≥150名儿童青少年作为... 详细信息

目的了解江苏省句容市儿童青少年碘营养状况、甲状腺结节流行状况及其分布特征,探讨儿童青少年甲状腺结节的危险因素。方法2021年采用整群抽样法在句容市城区、乡镇各抽取中、小学校1所,每所学校以班级为单位抽取≥150名儿童青少年作为调查对象,其中小学抽取三年级儿童、中学抽取七年级青少年。采用调查问卷和儿童焦虑性情绪障碍筛查表(SCARED)收集调查对象的基本信息及心理健康情况;采集调查对象所在学校和学校所在乡镇的水样,检测水碘含量;收集家庭食用盐盐样和尿样,检测盐碘和尿碘含量;采用B超法检查所有调查对象的甲状腺,测量甲状腺容积,分析甲状腺肿大(甲肿)及甲状腺结节情况。应用Cochran-Armitage趋势检验法进行趋势分析,采用多因素logistic回归模型分析甲状腺结节的危险因素。结果共调查儿童青少年710人(男性370人、女性340人),其中儿童347人(男性169人、女性178人)、青少年363人(男性201人、女性162人)。共采集水样14份,水碘含量范围为8.98~10.82μg/L,水碘中位数为9.98μg/L。共检测食用盐盐样710份,盐碘含量为(20.94±1.94)mg/kg,碘盐覆盖率为100.00%,合格碘盐食用率为97.46%(692/710)。共检测尿样710份,尿碘中位数为288.13μg/L,男性、女性尿碘中位数分别为310.29、245.12μg/L,二者比较差异有统计学意义(z=-5.91,P<0.001)。经B超检查发现,2021年句容市儿童青少年的甲肿率为2.25%(16/710),甲状腺结节检出率为25.07%(178/710),随着年龄增长甲状腺结节检出率未见明显上升趋势(χ^(2)_(趋势)=0.45,P=0.651);男性、女性甲状腺结节检出率分别为20.00%(74/370)和30.59%(104/340),二者比较差异有统计学意义(χ^(2)=10.57,P<0.001)。多因素logistic回归分析表明,女性、近1个月参加课外补习/兴趣班与儿童青少年发生甲状腺结节有关(OR=1.76、1.54,95%CI:1.25~2.49、1.09~2.17,均P<0.05)。结论2021年句容市儿童青少年碘盐覆盖率、合格碘盐食用率和甲肿率均达到碘缺乏病消除标准,碘营养处于超适宜量,但句容市外环境仍缺碘。儿童青少年甲状腺结节检出率处于较高水平,女性和近1个月参加课外补习/兴趣班是儿童青少年发生甲状腺结节的危险因素。

关键词：甲状腺结节儿童青少年 Logistic回归模型

固相外延生长法制备zSM-5@Silicalite-1分子筛及其CO_(2)加氢耦合甲苯烷基化反应的影响

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燃料化学学报（中英文） 2024年第8期52卷 1115-1130页

作者：贾艺敏牛鹏宇贾丽涛林明桂郭荷芹肖勇侯博李德宝中国科学院山西煤炭化学研究所煤炭高效低碳利用全国重点实验室山西太原030001 中国科学院大学北京100049 中国科学院洁净能源创新研究院辽宁大连116023

本研究采用固相法在zSM-5表面外延生长Silicalite-1,制备出zSM-5@Silicalite-1分子筛。同时制备高活性氧化物znzrOx,并与zSM-5@Silicalite-1物理混合组成znzrOx/zSM-5@Silicalite-1双功能催化剂,研究了CO_(2)加氢耦合甲苯烷基化催化性能。相比于znzrOx/zSM-5催化剂,分子筛改性后的双功能催化剂提高了对二甲苯(PX)选择性。研究了晶化条件(硅源、晶化过程、晶化次数)对zSM-5外延生长Silicalite-1的影响,以及Silicalite-1钝化层厚度对CO_(2)加氢耦合甲苯烷基化反应性能的影响。在400℃、3 MPa反应条件下,zzO/1:3.5z5-Na-SiO_(2)催化剂的甲苯转化率为12.0%,二甲苯选择性为77.4%,在二甲苯中对二甲苯选择性为73.4%。通过SEM、XRD、N2吸附-脱附、XPS、NH3-TPD、Py-FTIR等表征,研究了分子筛的结构和酸性质。结果表明,通过固相外延生长,延长zSM-5的孔道,增加间二甲苯(MX)、邻二甲苯(OX)的扩散阻力,同时钝化外表面的酸性,可以有效提高对二甲苯(PX)的选择性。固相外延生长法改性zSM-5分子筛,摒弃了以往堵塞孔以缩小孔口改性分子筛的缺点,在保证催化剂活性的同时提高了产物选择性。

关键词： MFI型分子筛外延生长对二甲苯固相法 CO_(2)加氢耦合甲苯烷基化

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局部干法水下焊接装置的研制

热加工工艺 2024年第7期53卷 76-79页

作者：侯瑞麟王妍高胜任永良张瑞明东北石油大学机械科学与工程学院黑龙江大庆163319

为了对核燃料池进行水下焊接,研制了一套局部干法水下焊接装置。通过搭建试验平台,采用该装置在亚克力池中进行了水下非熔化极惰性气体保护电弧焊试验,利用圆形补丁片对不锈钢壁面上的缺陷部位进行焊接修复。结果表明,焊后焊缝成形良好... 详细信息

为了对核燃料池进行水下焊接,研制了一套局部干法水下焊接装置。通过搭建试验平台,采用该装置在亚克力池中进行了水下非熔化极惰性气体保护电弧焊试验,利用圆形补丁片对不锈钢壁面上的缺陷部位进行焊接修复。结果表明,焊后焊缝成形良好,可以实现水下废池的修复,验证了该局部干法水下焊接装置的可行性。

关键词：水下焊接局部干法装置设计