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区间B样条小波有限元GPR模拟双相随机混凝土介质

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地球物理学报 2016年第8期59卷 3098-3109页

作者：冯德山王珣中南大学地球科学与信息物理学院长沙410083 有色资源与地质灾害探查湖南省重点实验室长沙410083

基于可分离小波理论,由一维区间B样条小波尺度函数的张量积构造二维B样条小波基,并将它作为GPR波动方程求解的插值函数,通过引入转换矩阵,实现小波系数空间与雷达电磁场之间的转换.应用Galerkin算法,推导了二维区间B样条小波有限元GPR... 详细信息

基于可分离小波理论,由一维区间B样条小波尺度函数的张量积构造二维B样条小波基,并将它作为GPR波动方程求解的插值函数,通过引入转换矩阵,实现小波系数空间与雷达电磁场之间的转换.应用Galerkin算法,推导了二维区间B样条小波有限元GPR波动方程离散格式,求出了2阶1尺度与2阶2尺度BSWI尺度函数的积分值及联系系数,给出了该算法的详细求解过程.编制了BSWI的Matlab模拟程序,应用该程序对两个典型实例进行了正演,结果表明:BSWI能采用较少的单元达到与FEM相似的精度,而BSWI算法尺度提升能提高解的精度,但耗时会急剧增加.最后,将BSWI算法应用于双相随机混凝土模型,说明随机介质模型理论能灵活、有效地描述实际混凝土介质的分布,正演剖面与实测剖面特征更相符,能更真实地模拟雷达波的传播过程,可为提高GPR的探测效果和解释准确性提供理论基础.

关键词：探地雷达区间B样条小波有限元正演模拟双相随机介质

基于差分光学吸收光谱法的大气甲醛和乙二醛研究

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光谱学与光谱分析 2016年第8期36卷 2384-2390页

作者：沈仕亮王珊珊周斌上海理工大学环境与建筑学院上海200093 复旦大学环境科学与工程系上海200433

介绍了一种基于差分光学吸收光谱技术对上海城市大气中HCHO和CHOCHO进行高时间分辨率的测定方法。针对HCHO和CHOCHO的不同吸收结构,选择适当的光谱分析波段,扣除干扰气体的吸收,有效降低残差,得到了用于反演目标气体的光学厚度,并进一... 详细信息

介绍了一种基于差分光学吸收光谱技术对上海城市大气中HCHO和CHOCHO进行高时间分辨率的测定方法。针对HCHO和CHOCHO的不同吸收结构,选择适当的光谱分析波段,扣除干扰气体的吸收,有效降低残差,得到了用于反演目标气体的光学厚度,并进一步获得2013年10月HCHO与CHOCHO的浓度变化特征。HCHO,CHOCHO平均浓度分别为(4.0±1.6)和(3.4±1.2)μg·m^(-3)。受人为源的影响,HCHO工作日平均浓度高于假期平均浓度,而CHOCHO的浓度相差不大。两者浓度的日变化趋势相似,早晨06:00—07:00出现最大值后迅速下降,到09:00左右出现最小值后又缓慢上升,并在夜间至日出前保持相对稳定的浓度水平。为探索大气HCHO可能的来源和生成过程,选取夜间稳态阶段,早高峰阶段,光化学反应阶段和晚高峰阶段等四个典型时段对HCHO的来源进行解析。NO_2作为HCHO的一次源指示物;同时作为光化学反应的中间产物,HCHO和CHOCHO生成机理具有相似性,因此以CHOCHO作为解析HCHO的二次源指示物,利用线性回归模型来源解析结果所得HCHO浓度与实际观测值具有较好的相关性,相关系数r为0.60~0.81,分析得出上海城区二次来源对环境HCHO浓度的贡献约为三分之一。

关键词：差分吸收光谱甲醛乙二醛来源解析

Single Image Deraining Using Residual Channel Attention Networks

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Journal of Computer Science & Technology 2023年第2期38卷 439-454页

作者：王迪潘金山唐金辉 School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Image deraining is a highly ill-posed *** significant progress has been made due to the use of deep convolutional neural networks,this problem still remains challenging,especially for the details restoration and generalization to real rain *** this paper,we propose a deep residual channel attention network(DeRCAN)for *** channel attention mechanism is able to capture the inherent properties of the feature space and thus facilitates more accurate estimations of structures and details for image *** addition,we further propose an unsupervised learning approach to better solve real rain images based on the proposed *** qualitative and quantitative evaluation results on both synthetic and real-world images demonstrate that the proposed DeRCAN performs favorably against state-of-the-art methods.

关键词： deraining deep convolutional neural network(DCNN) channel attention detail restoration unsupervised finetuning

Infection within 2 weeks before liver transplantation closely related to prognosis of posttransplant infection:A single-center retrospective observational study in China

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 358-364页

作者： Yue Ying Rui-Dong Li Jing-Wen Ai Yi-Min Zhu Xian Zhou Yi-Yi Qian Xin-Chang Chen Xu-Yang Wang Hao-Cheng Zhang Yang Li shan-shan Weng Yi-Qi Yu Yi-Feng Tao Yu-Xian Huang Zheng-Xin Wang Wen-Hong Zhang Department of Infectious Diseases Huashan HospitalFudan UniversityShanghai 200040China Department of General Surgery Huashan HospitalFudan UniversityShanghai 200040China

Background:Infections still represent the main factors influencing morbidity and mortality following liver *** study aimed to evaluate the incidence and risk factors for infection and survival after liver ***:We retrospectively examined medical records in 210 liver recipients who underwent liver transplantation between April 2015 and October 2017 in our *** manifestations and results of pathogen detection test were used to define *** analyzed the prevalence,risk factors and prognosis of patients with ***:The median follow-up was 214 days;the incidence of infection after liver transplantation was 46.7%(n=98)which included pneumonia(43.4%),biliary tract infection(21.9%),peritonitis(21.4%)and bloodstream infection(7.6%).Among the pathogens in pneumonia,the most frequently isolated was Acinetobacter baumanii(23.5%)and Klebsiella pneumoniae(21.2%).Model for end-stage liver disease(MELD)score(OR=1.083,95%CI:1.045–1.123;P<0.001),biliary complication(OR=4.725,95%CI:1.119–19.947;P=0.035)and duration of drainage tube(OR=1.040,95%CI:1.007–1.074;P=0.017)were independent risk factors for posttransplant ***-cause mortality was 11.0%(n=23).The prognostic factors for postoperative infection in liver recipients were prior-transplant infection,especially pneumonia within 2 weeks before ***-Meier curves of survival showed that recipients within 2 weeks prior infection had a significantly lower cumulative survival rate compared with those without infection(65.2%vs.90.0%;hazard ratio:4.480;P<0.001).Conclusions:Infection,especially pneumonia within 2 weeks before transplantation,complication with impaired renal function and MELD score after 7 days of transplantation was an independent prognostic factor for postoperative infection in liver transplant recipients.

关键词： Infection Liver transplantation Risk factors MELD score

Excellent ethanol sensor based on multiwalled carbon nanotube-doped ZnO

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Chinese Science Bulletin 2014年第4期59卷 374-378页

作者： Hao shan Changbai Liu Li Liu Lianyuan Wang Xiaobo Zhang Xiao Chi Xiaoqing Bo Kehong Wang State Key Laboratory of Superhard Materials College of Physics Jilin University College of Electronic Science & Engineering Jilin University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Multiwalled carbon nanotubes(MWNTs)were synthesized through CVD method,and the gas sensitive materials MWNTs/ZnO were obtained by mixing MWNTs and *** gas sensing properties of the as-prepared materials were *** results show that the gas sensing properties of ZnO sensor are significantly improved by doping *** sensitivity,response time and recovery time to 50 ppm ethanol at 260°C are 46,4 and 20 s,*** also examined the selectivity of 0.1 wt%MWNTs-doped ZnO sensors to different *** results show that the sensor possesses an excellent selectivity to ethanol.

关键词：多壁碳纳米管乙醇传感器 ZnO 掺杂敏感材料气敏性能 MWNTs CVD法

NEW TYPE OF DUAL BEM AND GREEN'S-FUNCTION-LIBRARY STRATEGY FOR FRACTURE ANALYSIS IN COMPLEX STRUCTURES

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Acta Mechanica Solida Sinica 2000年第4期13卷 363-373页

作者： Lu shan Huang Qiqing (Department of Aeroengine and Thermal Power Engineering,Northwestern Polytechnic University,Xi’an 710072,China) Dept. Aeroengine Thermal Pwr. Eng. Northwestern Polytechnic University Xi'an 710072 China

A new type of dual boundary integral equations(DBIE)is presented first,through which,a smaller system of equations needs to be solved in fracture *** a non-conforming crack tip element in two-dimensional problems is *** exact formula for the hypersingular integral over the non-con- forming crack tip element is given *** virtue of Green's-function-library strategy,a series of stress in- tensity factors(SIF)of different crack orientations,locations and/or sizes in a complicated structure can be obtained easily and ***,several examples of fracture analysis in two dimensions are given to demonstrate the accuracy and efficiency of the method proposed.

关键词： dual boundary element method hypersingular boundary integral equation stress intensity factor Green's function crack-tip element

Effects of SiC_(p) on microstructures of semi-solid extruded AZ91D magnesium alloys in recrystallization process

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China Foundry 2021年第6期18卷 565-573页

作者： Ao-xue Jiang Zhi-yong You Zhuang-zheng Duan Gang-ping Qiao Jin-shan Zhang Ling-bing Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China shanxi Huaxiang Group Co. Ltd.Linfen 041000ShanxiChina

AZ91 D and 8.5 vol.%SiC_(p)/AZ91 D magnesium matrix composites were fabricated by a semi-solid extruded processing method,and treated with solution and aging heat *** effects of SiC_(p)on the microstructures of the semi-solid extruded AZ91 D magnesium alloy during recrystallization were studied by observing and analyzing the microstructure evolution during extrusions and heat *** results show that the addition of SiC_(p)inhibits the dynamic recrystallization of AZ91 D during the semi-solid extrusion with only 26% of the volume fraction of ***,the addition of SiC_(p)refines the sizes of grains and second phases,and upgrades the volume fraction of second *** solution and aging treatment,the recrystallization continues,and the addition of SiC_(p)promotes the recrystallization and the recrystallized microstructure is much more ***,the sizes of grains and second phases continue to be refined,and the volume fraction of second phases continues to increase.

关键词： SiC_(p)/AZ91D composites semi-solid extrusion recrystallization microstructure

Evaluation of Left Ventricular Function by Three-Dimensional Speckle-Tracking Echocardiography in Patients with Chronic Kidney Failure

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Current Medical Science 2022年第4期42卷 895-901页

作者： Yu-bo WANG Hui HUANG shan LIN Mei-jia HAO Lu-jiao HE Kun LIU Xiao-jun BI Department of Ultrasound Third People's Hospital of Hubei ProvinceJianghan UniversityWuhan 430033China Department of Ultrasound Maternal and Child Health Hospital of Hubei ProvinceTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430070China Department of Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:To establish a quantitative evaluation of the left ventricle's systolic function in patients with chronic kidney failure(CKF)by three-dimensional speckle-tracking ***:Two-dimensional and three-dimensional transthoracic echocardiography was performed on 30 patients with *** ejection fraction,mass and global peak longitudinal strain,global circumferential strain,global area strain,and global radial strain of the left ventricle were ***:The ejection fraction,mass and global peak longitudinal strain(GLS),global circumferential strain(GCS),global area strain(GAS),and global radial strain(GRS)in the CKF group were significantly lower than those in the control ***,the GLS,GCS,GAS and GRS were well correlated with the ejection *** patients with normal ejection fraction in the CKF group,the GLS,GCS,GAS and GRS were lower than those in the control group,while the left ventricular mass was significantly higher in CKF patients than in the control *** patients with hypertension in the CKF group,ejection fraction,GLS,GCS,GAS and GRS calculated using three-dimensional echocardiography were significantly lower than those in patients with normal blood pressure;however,the myocardial mass was ***:The parameters(GLS,GCS,GAS and GRS)calculated using three-dimensional speckle-tracking software were lower in the CKF ***,the left ventricular mass was higher in CFK patients than in the control group,thus showing that the myocardial contraction function was impaired and that myocardial remodeling had occurred.

关键词： three-dimensional speckle-tracking echocardiography left ventricle ejection fraction strain chronic kidney failure

SOD2 Alleviates Hearing Loss Induced by Noise and Kanamycin in Mitochondrial DNA4834-deficient Rats by Regulating PI3K/MAPK Signaling

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Current Medical Science 2021年第3期41卷 587-596页

作者： Yan ZHANG shan HUANG Xiang DAI Zhong-fang XIA Han XIAO Xue-lian HE Rong YANG Jun LI Department of Otorhinolaryngology Wuhan Children's Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Reproductive Laboratory Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Biological Sample Bank Wuhan Children's Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Central Laboratory Wuhan Children's Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China Health Care Department Wuhan Children's HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430016China

Superoxide dismutase 2(SOD2)-mediated gene therapy has significant protective effects against kanamycin-induced hearing loss and hair cell loss in the inner ear,but the underlying mechanisms are still ***,an in vivo aging model of mitochondrial DNA(mtDNA)4834 deletion mutation was established using D-galactose,and the effects of noise or kanamycin on inner ear injury was *** subjected to mtDNA4834 mutation via D-galactose administration showed hearing loss characterized by the disruption of inner ear structure(abnormal cell morphology,hair cell lysis,and the absence of the organ of Corti),increased SOD2 promoter methylation,and an increase in the degree of *** to noise or kanamycin further contributed to the effects of ***2 overexpression induced by viral injection accordingly counteracted the effects of noise and kanamycin and ameliorated the symptoms of hearing loss,suggesting the critical involvement of SOD2 in preventing deafness and hearing-related *** PI3K and MAPK signaling pathways were also regulated by noise/kanamycin exposure and/or SOD2 overexpression,indicating that they may be involved in the therapeutic effect of SOD2 against age-related hearing loss.

关键词： hearing loss methylation mtDNA4834 deletion mutation superoxide dismutase 2