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Research on Concrete Beam Crack Recognition Algorithm Based on Block Threshold Value Image Processing

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Structural Durability & Health Monitoring 2020年第4期14卷 355-374页

作者： Wenting Qiao xiaoguang wu Wen Sun Qiande wu School of Highway Chang'an UniversityXi'an710064China Iner Mongolia Transport Construction Engineering Quality Supervision Bureau Hohhot010020China Jiangsu Fasten Matenial Analysis and Inspecting Co LtdJiangyin214446China School of Civil Engineering Southeast UniversityNanjing210000China

To solve the problem that the digital image recognition accuracy of concrete structure cracks is not high under the condition of uneven ill umination and complex surface color of concrete structure,this paper has proposed a block segmentation method of maximum entropy threshold based on the digital image data obtained by the ACTIS automatic detection *** steps in this research are as follows:*** crack digital images of concrete specimens with typical fea-tures were collected by using the Actis system of KURABO Co,Ltd,of Japan in the concrete beam bending *** images are segmented into blocks to dis-tinguish backgrounds of different *** max imum interclass average gray difference method is used to distinguish the sub-blocks and screen out the image blocks that need to be *** is made to the image with 2D max imum entropy threshold segmentation method to obtain the binary image,and the target image can be obtained by screening the connected domain features of the binary *** have shown that compared with other algo-rithms,the proposed method can effectively decrease the image over-segmentation and under segmentation rates,highlight the characteristics of the target cracks,solve the problems of excessive difference between the identified length and actual length of cracks caused by background gray level change and uneven ilumnination,and effectively improve the recognition accuracy of bridge concrete cracks.

关键词： Concrete crack block segmentation maximum entropy segmentation algorithms maximum interclass variance(Otsu)method

Analysis of period doubling bifurcation and chaos mirror of biped passive dynamic robot gait

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Chinese Science Bulletin 2012年第14期57卷 1743-1750页

作者： ZHAO Jie wu xiaoguang ZANG XiZhe YAN JiHong State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150080 China

With a reasonable parameter configuration,the passive dynamic walking model has a stable,efficient,natural periodic gait,which depends only on gravity and inertia when walking down a slight *** fact,there is a delicate balance in the energy conversion in the stable periodic gait,making the gait adjustable by changing the model ***é mapping is combined with Newton-Raphson iteration to obtain the numerical solution of the final state of the passive dynamic walking *** addition,a simulation on the walking gait of the model is performed by increasing the slope step by step,thereby fixing the model's parameters ***,the gait features obtained in the different slope stages are analyzed and discussed,the intrinsic laws are revealed in *** results indicate that the gait can present features of a single period,doubling period,the entrance of chaos,merging of sub-bands,and so on,because of the high sensitivity of the passive dynamic walking to the *** a global viewpoint,the gait becomes chaotic by way of period doubling bifurcation,with a self-similar Feigenbaum fractal structure in the *** the entrance of chaos,the gait sequence comprises a Cantor set,and during the chaotic stage,sub-bands in the final-state diagram of the robot system present as a mirror of the period doubling bifurcation.

关键词：倍周期分岔步态分析机器人系统 Cantor集模型参数混沌动态行走参数配置

Real-Time Edge Enhancement Using KNSBN at 633 nm

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Chinese Physics Letters 1991年第4期8卷 184-186页

作者： wu xiaoguang SHAO Zongshu CHEN Huanchu SONG Yongyuan SUN Daliang Department of Optics Shandong UniversityJinan 250100 Institute of Crystal Materials Shandong UniversityJinan 250100

Edge enhancement has been performed in Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y)Nb_(2)O_(6)(KNSBN)crystal at 633nm with low incident-light intensities 10^(-3)W/cm^(2).We calculated the expected images w... 详细信息

关键词： KNSBN incident crystal

Observation of Self-pumped Phase Conjugation for Two Mutually Coherent Input Beams in a KNSBN Crystal

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Chinese Physics Letters 1993年第6期10卷 340-342页

作者： wu xiaoguang HU Xierong SHAO Zhongsu CHEN Huanchu SONG Yongyuan Department of Optics Shandong UniversityJinan 250100 Institute of Crystal Materials Shandong UniversityJinan 250100

Two coherent or incoherent stable self-pumped phase conjugations have been obtained simultaneously in a Ce-doped(K_(0.5)Na_(0.5))_(2y)(Sr_(0.61)Ba_(0.39))_(1-y) Nb_(2)O_(6)(KNSBN)crystal by using two mutually coherent input beams from a He-Ne laser,and energy translation from one beam to another induces self-pumped phase conjugative reflectivity of one beam above 100%.

关键词： pumped Crystal coherent

Synthesis and proton conductibility of ternary germanic heteropoly acids

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Rare Metals 2004年第4期23卷 296-299页

作者： SANGxiaoguang wuQingyin DepartmentofChemistry ZhejiangUniversityHangzhou310027China

The ternary germanic heteropoly acids H_5GeW_(11)O_(40) centre dot 22H_2O andH_5GeMo_(11)VO_(40) centre dot 24H_2O were synthesized for the first time by the stepwiseacidification and the stepwise addition of solution of the component elements. The products werecharacterized by ICP, IR, UV, XRD and TG-DTA. The proton conductibility and the activation energy ofproton conduction of the heteropoly acids were investigated.

关键词： inorganic solid chemistry heteropoly acid synthesis Keggin structure germanium tungsten molybdenum vanadium conductivity activation energy

Nonlinear Fabry-Perot Etalon and Optical Bistability in CdHgTe at 77K

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Chinese Physics Letters 1992年第10期9卷 523-526页

作者： wu xiaoguang HU Xierong YANG Yawen SU Jingwen CHEN Jishu Department of Optical Shandong UniversityJinan 250100 Department of Physics Shanghai UniversityShanghai 200234 Shanghai Institute of Technical Physics Academia SinicaShanghai 200083 Department of Physics Ningbo UniversityNingbo 315211

We report the first observations of nonlinear feature and optical bistability in n-CdHgTe at 77K and obtained computer simulated curves,then discuss contribution due to thermal effect.

关键词： effect. stability Nonlinear

电针联合低频经颅超声刺激对创伤性脑损伤大鼠脑电信号的影响

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中国组织工程研究 2025年第2期29卷 402-408页

作者：高思淼韩雪吴晓光郑金钰高芳雯李葵花彭勇刘兰祥承德医学院河北省神经损伤与修复重点实验室河北省承德市067000 承德医学院生物医学工程系河北省承德市067000 承德医学院附属医院神经内科河北省承德市067000 承德医学院河北省医工结合国际研究中心河北省承德市067000 燕山大学电气工程学院河北省秦皇岛市066004 燕山大学河北省智能康复及神经调控重点实验室河北省秦皇岛市066004 秦皇岛市第一医院河北省秦皇岛市066004

背景:创伤性脑损伤是由头部受到撞击、打击而导致大脑正常功能被破坏的疾病,目前需要寻找有效治疗方式和客观指标,帮助医生判别损伤状况及恢复患者脑功能。目的:探究电针联合低频经颅超声刺激对创伤性脑损伤大鼠脑电信号的影响。方法:... 详细信息

背景:创伤性脑损伤是由头部受到撞击、打击而导致大脑正常功能被破坏的疾病,目前需要寻找有效治疗方式和客观指标,帮助医生判别损伤状况及恢复患者脑功能。目的:探究电针联合低频经颅超声刺激对创伤性脑损伤大鼠脑电信号的影响。方法:将40只6周龄SPF级雄性SD大鼠随机分为假手术组、模型组、电针组、低频经颅超声刺激组和联合组(n=8),后4组采用Feeney自由落体法造模,假手术组只开骨窗而不打击。各干预组均于造模后1 d开始实施干预,电针组进行电针干预,低频经颅超声刺激组进行低频经颅超声刺激干预,联合组进行两者联合干预,共干预7 d。造模后8 h,用改良神经功能缺损评分评定大鼠神经功能缺损情况;干预7 d后观察大鼠Y迷宫自发轮流行为百分比,而后采集脑电信号,利用快速傅里叶变换分解出α、β、θ和δ波段,计算各频段振荡幅值、能量占比百分比以及Lempel-Ziv复杂度、样本熵。结果与结论:①造模后8 h,模型组、电针组、低频经颅超声刺激组和联合组的改良神经功能缺损评分显著高于假手术组(P<0.05);②造模后第7天,模型组的α波、δ波频带振荡幅值、δ波能量占比百分比显著高于假手术组(P<0.05),自发轮流行为百分比、α波、β波能量占比百分比、Lempel-Ziv复杂度、样本熵显著低于假手术组(P<0.05);③与模型组比较,联合组的α波、δ波频带振荡幅值显著下降(P<0.05),电针组、低频经颅超声刺激组、联合组的α波、β波频带能量占比百分比显著升高(P<0.05),δ波能量占比百分比显著下降(P<0.05);④与电针组和低频经颅超声刺激组相比,联合组的δ波能量占比百分比显著降低(P<0.05),自发轮流行为百分比、α波、β波能量占比百分比、Lempel-Zi复杂度、样本熵显著升高(P<0.05);⑤结果显示,创伤性脑损伤大鼠出现脑电信号异常,而电针联合低频经颅超声刺激干预后可以改善大鼠脑电信号的异常情况,提示脑电频域特征和非线性特征可用来评估创伤性脑损伤情况。

关键词：创伤性脑损伤电针低频经颅超声刺激脑电信号神经功能

Efficacy and Safety of Combined Bedaquiline and Delamanid Use among Patients with Multidrug-Resistant Tuberculosis in Beijing,China

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Biomedical and Environmental Sciences 2024年第10期37卷 1195-1203页

作者： Can Guo Lihui Nie Yanhua Song Rongmei Liu xiaoguang wu Yuanyuan Shang Xuxia Zhang Yu Pang Mengqiu Gao Department of Tuberculosis Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China Department of Bacteriology and Immunology Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China

Objectives The combined use of bedaquiline and delamanid(BDQ-DLM)is limited by an increased risk of prolonging the QTc *** retrospectively evaluated patients who received DLM/BDQcontaining regimens at a TB-specialized *** aimed to present clinical efficacy and safety data for Chinese *** This case-control study included patients with multidrug-resistant tuberculosis(MDR-TB)treated with BDQ alone or BDQ plus *** A total of 96 patients were included in this analysis:64 in the BDQ group and 32 in the BDQ+DLM *** the 96 patients with positive sputum culture at the initiation of BDQ alone or BDQ combined with DLM,46 patients(71.9%)in the BDQ group and 29(90.6%)in the BDQ-DLM group achieved sputum culture conversion during *** rate of sputum culture conversion did not differ between the two *** time to sputum culture conversion was significantly shorter in the BDQ-DLM group than in the BDQ *** most frequent adverse event was QTc interval prolongation;however,the frequency of adverse events did not differ between the *** In conclusion,our results demonstrate that the combined use of BDQ and DLM is efficacious and tolerable in Chinese patients infected with *** in the BDQ-DLM group achieved sputum culture conversion sooner than those in the BDQ group.

关键词： Multidrug resistant Tuberculosis Bedaquiline Delamanid Efficacy Safety

Magnetic rotation in Rubidium-84

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Nuclear Science and Techniques 2013年第3期24卷 61-65页

作者： SHEN Shuifa HAN Guangbing WEN Shuxian YAN Yupeng wu xiaoguang ZHU Lihua HE Chuangye LI Guangsheng Institute of Nuclear Energy Safety Technology Chinese Academy of Sciences School of Physics Suranaree University of Technology Thailand Center of Excellence in Physics (ThEP) Commission on Higher Education State Key Laboratory of Nuclear Physics and Technology (Peking University) School of Physics Shandong University China Institute of Atomic Energy P. O. Box 275(10) School of Physics and Nuclear Energy Engineering Beihang University

High-spin states in 84 Rb have been studied by using the 70Zn(18O, p3n)84Rb reaction at beam energy of 75MeV. Three regular magnetic dipole bands including strong M1 and weak E2 transitions have been observed in this nucleus which shows the characteristic feature of magnetic rotation. These bands are interpreted in the projected shell model for the first time on the basis of the four-quasiparticle configuration of the type π(fp)π(g29/2)v(g9/2). It is shown that the calculated sequence lies roughly in the same energy range as the experimental one but the interval between neighboring levels is larger than the corresponding experimental value. We believe that a 4-quasiparticle band crossing with the 2-quasiparticle band will depress the energies of the states.

关键词：磁旋转电子束能量投影壳模型高自旋态磁偶极子 E2跃迁能量范围时间间隔