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经胸微创介入术治疗小儿先天性心脏病复合畸形的疗效 被引量:35
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作者 刘宇航 王宁 +5 位作者 赵烨 刘大为 卢绪宁 朱全伟 高明磊 文平 《中华实用儿科临床杂志》 CSCD 北大核心 2018年第13期1018-1021,共4页
目的探讨经食管超声(TEE)引导经胸微创介入术治疗小儿先天性心脏病(先心病)复合畸形的安全性及有效性。方法选取2013年9月至2018年1月在大连市儿童医院心外科行经胸微创介入术的32例先心病复合畸形患儿,其中室间隔缺损(VSD)并房... 目的探讨经食管超声(TEE)引导经胸微创介入术治疗小儿先天性心脏病(先心病)复合畸形的安全性及有效性。方法选取2013年9月至2018年1月在大连市儿童医院心外科行经胸微创介入术的32例先心病复合畸形患儿,其中室间隔缺损(VSD)并房间隔缺损(ASD)6例,VSD并动脉导管未闭(PDA)11例,ASD并PDA 9例,VSD并肺动脉瓣狭窄(PS)3例,ASD并PS 3例。手术均为非体外循环下经TEE引导经胸小切口(1~2 cm)由输送器置入封堵器封堵缺损或置入球囊扩张肺动脉瓣。术后即刻通过TEE评价手术疗效,患儿出院后均在大连市儿童医院门诊随访复查超声心动图、心电图和胸片。结果32例患儿经胸微创介入治疗均获得成功,无一例中转开胸心脏直视手术。手术时间(54.2±21.8) min,重症监护室监护时间(14.3±8.7) h,通气时间(3.7±2.9) h。患儿均不需要强心利尿药物、输血或镇静药物。随访12~48个月,无心律失常、残余分流、封堵器脱落、血栓、出血、新发瓣膜反流发生。结论掌握好正确的方法及适应证,对先心病复合畸形患儿实施TEE下引导经胸微创介入术安全,且预后良好。 展开更多
关键词 先天性心脏病 食管超声 复合畸形 儿童 经胸微创
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Current status of diagnosis and treatment of bladder cancer in China-Analyses of Chinese Bladder Cancer Consortium database 被引量:33
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作者 Kaiwen Li Tianxin Lin +87 位作者 Wei Xue Xin Mu Enci Xu Xu Yang Fubao Chen Guangyong Li lulin Ma Guoliang Wang Chaozhao Liang Haoqiang Shi Ming Li Mao Tang Xueyi Xue Yisong Lv Yaoliang Deng Chengyang Li Zhiwen Chen Xiaozhou Zhou Fengshuo Jin Xudong Liu Jinxin Wei Lei Shi Xin Gou Weiyang He Liqun Zhou Lin Cai Baiye Jin Guanghou Fu Xiangbo Kong Hongyan Sun Ye Tian Lang Feng Tiejun Pan Yiyi Wu Dongwen Wang Hailong Hao Benkang Shi Yaofeng Zhu Qiang Wei Ping Han Changli Wu dawei Tian Zhangqun Ye Zheng Liu Zhiping Wang Junqiang Tian Lin Qi Minfeng Chen Wei Li Jinchun Qi Gongxian Wang Longlong Fu Zhaolin Sun Guangheng luo Zhoujun Shen Zhaowei Zhu Jinchun Xing Zhun Wu Dong Wei Xin Chen Yanqun Na Hongfeng Guo Chunxi Wang Zhihua lu Chuize Kong Yang Liu Jin Yang Jianyun Hu Xin Gao Jielin Li Changjun Yin Pu Li Shan Chen Zhen Du Jiongming Li Yongji Yan Xu Zhang Shuang Huang Fangjian Zhou Zhiling Zhang Yinghao Sun Shuxiong Zeng Song Cen Jiaquan Zhou Hanzhong Li Jin Wen Jian Huang 《Asian Journal of Urology》 2015年第2期63-69,共7页
Objective:To investigate current status of diagnosis and treatment of bladder cancer in China.Methods:A database was generated by Chinese Bladder Cancer Consortium(CBCC).From January 2007 to December 2012,14,260 cases... Objective:To investigate current status of diagnosis and treatment of bladder cancer in China.Methods:A database was generated by Chinese Bladder Cancer Consortium(CBCC).From January 2007 to December 2012,14,260 cases from 44 CBCC centers were included.Data of diagnosis,treatment and pathology were collected.Results:The average age was 63.5 year-old and most patients were male(84.3%).The most common histologic types were urothelial carcinoma(91.4%),adenocarcinoma(1.8%),and squamous carcinoma(1.9%).According to 1973 and 2004 WHO grading system,42.0%,41.0%,and 17.0% of patients were grade 1,2,and 3,and 16.0%,48.7%,and 35.3% of patients were papillary urothelial neoplasms of low malignant potential,low,and high grade,respectively.Non-muscle invasive bladder cancer(NMIBC)and muscle invasive bladder cancer(MIBC)were 25.2% and 74.1%,respectively(0.8% not clear).Carcinoma in situ was only 2.4%.Most patients were diagnosed by white-light cystoscopy with biopsy(74.3%).Fluorescence and narrow band imaging cystoscopy had additional detection rate of 1.0% and 4.0%,respectively.Diagnostic transurethral resection(TUR)provided detection rate of 16.9%.Most NMIBCs were treated with TUR(89.2%).After initial TUR,2.6%accepted second TUR,and 45.7%,69.9%,and 58.7% accepted immediate,induced,and maintenance chemotherapy instillation,respectively.Most MIBCs were treated with radical cystectomy(RC,59.7%).Laparoscopic RCs were 35.1%,while open RC 63.4%.Extended and standard pelvic lymph node dissection were 7% and 66%,respectively.Three most common urinary diversions were orthotopic neobladder(44%),ileal conduit(31%),and ureterocutaneostomy(23%).Only 2.3% of patients accepted neo-adjuvant chemotherapy and only 18%of T3 and T4 patients accepted adjuvant chemotherapy.Conclusion:Disease characteristics are similar to international reports,while differences of diagnosis and treatment exist.This study can provide evidences for revisions of the guideline on bladder cancer in China. 展开更多
关键词 Bladder cancer DIAGNOSIS Treatment
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The linkage maps of Dendrobium species based on RAPD and SRAP markers 被引量:27
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作者 dawei Xue Shangguo Feng +6 位作者 Hongyan Zhao Hua Jiang Bo Shen Nongnong Shi Jiangjie lu Junjun Liu Huizhong Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第3期197-204,共8页
Dendrobium plants are used commonly as tonic herbs and health food in many Asian countries, especially in China. Here we report the genetic map construction of two Dendrobium species with a double pseudo-testcross str... Dendrobium plants are used commonly as tonic herbs and health food in many Asian countries, especially in China. Here we report the genetic map construction of two Dendrobium species with a double pseudo-testcross strategy using random amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP) markers. A F1 mapping population of 90 individuals was developed from a cross between D. officinale and D. hercoglossum. A total of 307 markers, including 209 RAPD and 98 SRAP, were identified and used for genetic linkage group (LG) analysis. The D. officinale linkage map consisted of 11 major linkage groups and 3 doublets, which covered 629.4 cM by a total of 62 markers with an average locus distance of 11.2 cM between two adjacent markers. The D. hercoglos- sum linkage map contained 112 markers mapped on 15 major and 4 minor linkage groups, spanning a total length of 1,304.6 cM with an average distance of I 1.6 cM between two adjacent markers. The maps constructed in this study covered 92.7% and 82.7% of the D. hercoglossum and D. officinale genomes respectively, providing an important basis for the mapping of horticultural and medicinal traits and for the application of marker-assisted selection in Dendrobium breeding program. 展开更多
关键词 DENDROBIUM genetic linkage map RAPD SRAP
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Robustness evaluation method for unmanned aerial vehicle swarms based on complex network theory 被引量:25
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作者 Xiaohong WANG Yuan ZHANG +2 位作者 Lizhi WANG dawei lu Guoqi ZENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期352-364,共13页
Unmanned Aerial Vehicle(UAV)swarms have been foreseen to play an important role in military applications in the future,wherein they will be frequently subjected to different disturbances and destructions such as attac... Unmanned Aerial Vehicle(UAV)swarms have been foreseen to play an important role in military applications in the future,wherein they will be frequently subjected to different disturbances and destructions such as attacks and equipment faults.Therefore,a sophisticated robustness evaluation mechanism is of considerable importance for the reliable functioning of the UAV swarms.However,their complex characteristics and irregular dynamic evolution make them extremely challenging and uncertain to evaluate the robustness of such a system.In this paper,a complex network theory-based robustness evaluation method for a UAV swarming system is proposed.This method takes into account the dynamic evolution of UAV swarms,including dynamic reconfiguration and information correlation.The paper analyzes and models the aforementioned dynamic evolution and establishes a comprehensive robustness metric and two evaluation strategies.The robustness evaluation method and algorithms considering dynamic reconfiguration and information correlation are developed.Finally,the validity of the proposed method is verified by conducting a case study analysis.The results can further provide some guidance and reference for the robust design,mission planning and decision-making of UAV swarms. 展开更多
关键词 Complex networks Dynamic RECONFIGURATION Information correlation ROBUSTNESS evaluation Unmanned AERIAL Vehicles(UAV)
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北运河沙河水库沉积物营养盐分布特征及其溯源分析 被引量:24
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作者 孙文 王理明 +6 位作者 刘吉宝 张俊亚 郁达伟 佃柳 卢铁东 张爽 魏源送 《环境科学学报》 CAS CSCD 北大核心 2019年第5期1581-1589,共9页
通过采集沙河水库表层(0~20 cm)沉积物样品,分析了沉积物中氮、磷、有机质的分布特征,并结合排污口附近和水库典型区域沉积物中有机质(Organic Matter, OM)和溶解性有机物(Dissolved Organic Matter, DOM)的荧光光谱特征、分子量分布特... 通过采集沙河水库表层(0~20 cm)沉积物样品,分析了沉积物中氮、磷、有机质的分布特征,并结合排污口附近和水库典型区域沉积物中有机质(Organic Matter, OM)和溶解性有机物(Dissolved Organic Matter, DOM)的荧光光谱特征、分子量分布特征(Molecular Weight Distribution, MWD),研究了点源污染对沙河水库沉积物营养盐分布的潜在影响.结果表明,表层沉积物间隙水中氨氮(NH^+_4-N)、磷酸盐(PO■-P)平均浓度及沉积物中总氮(TN)、总磷(TP)的平均含量依次为(52.13±40.32)、(1.75±1.88) mg·L^(-1)与(2853.81±1501.93)、(1496.00±454.06) mg·kg^(-1).库区沉积物中TN、TP含量由库上游((1898.00±1047.54)、(1264.00±104.61) mg·kg^(-1))经库心区((2996.67±1405.13)、(1340.00±332.47) mg·kg^(-1))至库下游((4500.00±920.00)、(1750.00±10.00) mg·kg^(-1))依次增高.沉积物C/N比分析表明,点源污染区与库区沉积物中有机质来源于陆源与自生生物源的混合源.而三维荧光光谱和分子量分布的分析表明,点源污染区与库区沉积物中DOM的组成特性具有一致性,且主要来源于自生生物源.Pearson相关性分析表明,沉积物中营养盐(TN、TP)与有机质具有显著相关关系(p<0.01).这些结果清楚地表明,点源污染区沉积物中高的营养盐、有机质含量是库区污染物累积的潜在重要来源. 展开更多
关键词 点源污染 沉积物 营养盐 空间分布 溯源
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早期不同分期糖尿病视网膜病变黄斑区血流密度及血管结构改变 被引量:23
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作者 曾运考 杨大卫 +4 位作者 曹丹 余洪华 卢曼虹 庄雪楠 张良 《中华实验眼科杂志》 CAS CSCD 北大核心 2020年第9期783-787,共5页
目的利用光相干断层扫描血管成像技术(OCTA)探究早期不同分期糖尿病视网膜病变(DR)患者的黄斑区局部血流密度及其结构特征。方法采用横断面研究设计,选取2017年6月至2018年8月在广东省人民医院就诊的非糖尿病视网膜病变的糖尿病(NDR)患... 目的利用光相干断层扫描血管成像技术(OCTA)探究早期不同分期糖尿病视网膜病变(DR)患者的黄斑区局部血流密度及其结构特征。方法采用横断面研究设计,选取2017年6月至2018年8月在广东省人民医院就诊的非糖尿病视网膜病变的糖尿病(NDR)患者27例40眼、轻度非增生性DR(NPDR)患者24例40眼以及中度NPDR患者28例40眼,同期纳入正常体检者40名40眼作为正常对照组。利用RTVue-XR OCTA扫描受检者黄斑区中心6 mm×6 mm范围量化浅层毛细血管丛(SVC)及深层毛细血管丛(DVC)血流密度,中心凹无血管区(FAZ)面积、周长、非圆度指数(AI)及FAZ旁300 μm环形区域(FD300)的血流密度等参数。分析各组黄斑区SVC、DVC血流密度及结构的特征,及其与疾病进程的关系。结果随着DR的程度加重,黄斑区SVC及DVC血流密度呈下降趋势。正常对照组、NDR组、轻度NPDR组及中度NPDR组SVC血流密度分别为(51.25±3.27)%、(48.81±3.99)%、(47.00±3.49)%和(45.73±3.35)%,DVC血流密度分别为(53.89±6.30)%、(49.94±6.05)%、(46.69±4.87)%和(44.78±4.30)%,总体比较差异均有统计学意义(F=18.33、21.53,均P<0.01)。NDR组、轻度NPDR组及中度NPDR组黄斑区SVC及DVC血流密度均明显低于正常对照组,差异均有统计学意义(均P<0.01)。轻度NPDR组及中度NPDR组FD300血流密度均明显低于正常对照组,差异均有统计学意义(均P<0.01)。正常对照组、NDR组、轻度及中度NPDR组的FAZ面积分别为(0.31±0.11)、(0.32±0.09)、(0.34±0.13)和(0.37±0.10)mm2;各组FAZ面积总体比较,差异无统计学意义(F=2.18,P=0.09)。中度NPDR组FAZ周长及AI均大于正常对照组,差异均有统计学意义(均P<0.05)。结论在糖尿病患者出现临床可见眼底病变前,OCTA即可发现黄斑区视网膜血流密度明显下降。早期DR已出现黄斑区SVC及DVS血流密度下降,DVC血流密度可能是提示DR的敏感指标。轻度NPDR出现FD300血流密度下降,而中度NPDR出现FAZ面积� 展开更多
关键词 糖尿病/并发症 糖尿病视网膜病变/诊断 黄斑 血流密度 光相干断层扫描血管成像
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Insight-HXMT observations of the first binary neutron star merger GW170817 被引量:20
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作者 TiPei Li ShaoLin Xiong +107 位作者 ShuangNan Zhang FangJun lu LiMing Song XueLei Cao Zhi Chang Gang Chen Li Chen TianXiang Chen Yong Chen YiBao Chen YuPeng Chen Wei Cui WeiWei Cui JingKang Deng YongWei Dong YuanYuan Du MinXue Fu GuanHua Gao He Gao Min Gao MingYu Ge YuDong Gu Ju Guan ChengCheng Guo dawei Han Wei Hu Yue Huang Jia Huo ShuMei Jia luHua Jiang WeiChun Jiang Jing Jin YongJie Jin Bing Li ChengKui Li Gang Li MaoShun Li Wei Li Xian Li XiaoBo Li XuFang Li YanGuo Li ZiJian Li ZhengWei Li XiaoHua Liang JinYuan Liao CongZhan Liu GuoQing Liu HongWei Liu ShaoZhen Liu XiaoJing Liu Yuan Liu YiNong Liu Bo lu XueFeng lu Tao luo Xiang Ma Bin Meng Yi Nang JianYin Nie Ge OU Jinlu Qu Na Sai Liang Sun Yin Tan Lian Tao WenHui Tao YouLi Tuo GuoFeng Wang HuanYu Wang Juan Wang WenShuai Wang YuSa Wang XiangYang Wen BoBing WU Mei Wu GuangCheng Xiao He Xu YuPeng Xu LinLi Yan JiaWei Yang Sheng Yang YanJi Yang AiMei Zhang ChunLei Zhang ChengMo Zhang Fan Zhang HongMei Zhang Juan Zhang Qiang Zhang Shu Zhang Tong Zhang Wei Zhang WanChang Zhang WenZhao Zhang Yi Zhang Yue Zhang YiFei Zhang YongJie Zhang Zhao Zhang ZiLiang Zhang HaiSheng Zhao JianLing Zhao XiaoFan Zhao ShiJie Zheng Yue Zhu YuXuan Zhu ChangLin Zou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第3期26-33,共8页
Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, cosmology and fundament... Finding the electromagnetic (EM) counterpart of binary compact star merger, especially the binary neutron star (BNS) merger, is critically important for gravitational wave (GW) astronomy, cosmology and fundamental physics. On Aug. 17, 2017, Advanced LIGO and Fermi/GBM independently triggered the first BNS merger, GW170817, and its high energy EM counterpart, GRB 170817A, respectively, resulting in a global observation campaign covering gamma-ray, X-ray, UV, optical, IR, radio as well as neutrinos. The High Energy X-ray telescope (HE) onboard Insight-HXMT (Hard X-ray Modulation Telescope) is the unique high-energy gamma-ray telescope that monitored the entire GW localization area and especially the optical counterpart (SSS17a/AT2017gfo) with very large collection area (M000 cm2) and microsecond time resolution in 0.2-5 MeV. In addition, Insight-HXMT quickly implemented a Target of Opportunity (TOO) observation to scan the GW localization area for potential X-ray emission from the GW source. Although Insight-HXMT did not detect any significant high energy (0.2-5 MeV) radiation from GW170817, its observation helped to confirm the unexpected weak and soft nature of GRB 170817A. Meanwhile, Insight-HXMT/HE provides one of the most stringent constraints (-10-7 to 104 erg/cm2/s) for both GRB170817A and any other possible precursor or extended emissions in 0.2-5 MeV, which help us to better understand the properties of EM radiation from this BNS merger. Therefore the observation of Insight-HXMT constitutes an important chapter in the full context of multi-wavelength and multi-messenger observation of this historical GW event. 展开更多
关键词 GW170817 BNS merger gravitational wave electromagnetic counterpart
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Overview to the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite 被引量:18
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作者 Shuang-Nan Zhang TiPei Li +116 位作者 FangJun lu LiMing Song YuPeng X u CongZhan Liu Yong Chen XueLei Cao QingCui Bu Zhi Chang Gang Chen Li Chen TianXiang Chen YiBao Chen YuPeng Chen Wei Cui WeiWei Cui JingKang Deng YongWei Dong Yuan Yuan Du MinXue Fu GuanHua Gao He Gao Min Gao MingYu Ge YuDong Gu Ju Guan Can Gungor ChengCheng Guo dawei Han Wei Hu Yue Huang Jia Huo ShuMei Jia luHua Jiang WeiChun Jiang Jing Jin YongJie Jin Bing Li ChengKui Li Gang Li MaoShun Li Wei Li Xian Li XiaoBo Li XuFang Li YanGuo Li ZiJian Li ZhengWei Li XiaoHua Liang JinYuan Liao GuoQing Liu HongWei Liu ShaoZhen Liu XiaoJing Liu Yuan Liu YiNong Liu Bo lu XueFeng lu Tao luo Xiang Ma Bin Meng Yi Nang JianYin Nie Ge Ou Jinlu Qu Na Sai RenCheng Shang GuoHong Shen Liang Sun Ying Tan Lian Tao YouLi Tuo Chen Wang ChunQin Wang GuoFeng Wang HuanYu Wang Juan Wang WenShuai Wang YuSa Wang XiangYang Wen BaiYang Wu BoBing Wu Mei Wu GuangCheng Xiao ShaoLin Xiong LinLi Yan JiaWei Yang Sheng Yang YanJi Yang QiBin Yi Bin Yuan AiMei Zhang ChunLei Zhang ChengMo Zhang Fan Zhang HongMei Zhang Juan Zhang Qiang Zhang ShenYi Zhangs Shu Zhang Tong Zhang WanChang Zhang Wei Zhang WenZhao Zhang Yi Zhang YiFei Zhang YongJie Zhang Yue Zhang Zhao Zhang Zhi Zhang ZiLiang Zhang HaiSheng Zhao XiaoFan Zhao ShiJie Zheng JianFeng Zhou YuXuan Zhu Yue Zhu RenLin Zhuang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第4期2-19,共18页
As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray as... As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 Me V. It was designed to perform pointing, scanning and gamma-ray burst(GRB)observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be reconstructed.Here we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results. 展开更多
关键词 X-and γ-ray telescopes and instrumentation neutron stars black holes X-ray binaries γ-ray bursts
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基于无人机前端和SSD算法的输电线路部件检测模型对比研究 被引量:19
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作者 杨罡 孙昌雯 +4 位作者 王大伟 晋涛 徐澄宇 卢志博 张兴忠 《太原理工大学学报》 CAS 北大核心 2020年第2期212-219,共8页
基于深度学习的目标检测技术因其自身复杂的模型结构和对算力的需求,导致应用于无人机输电线路巡检中无法在机载前端实现高效且准确的检测。针对这一问题,面向输电线路无人机前端巡检中绝缘子、悬垂线夹及防震锤3类部件,选取Single Shot... 基于深度学习的目标检测技术因其自身复杂的模型结构和对算力的需求,导致应用于无人机输电线路巡检中无法在机载前端实现高效且准确的检测。针对这一问题,面向输电线路无人机前端巡检中绝缘子、悬垂线夹及防震锤3类部件,选取Single Shot MultiBox Detector(SSD)目标检测算法,通过使用不同的骨干网络对比性能差异,选择最佳网络结构并采用特征融合手段提高检测准确率。实验结果表明,采用Mobilenet_v1作为SSD的骨干网络进行特征提取,并融合不同层次特征进行检测,Mean Average Precision(mAP)可达90.21%,在具有边缘计算能力的嵌入式设备上可以达到每张63 ms的检测速度。为输电线路无人机前端实时检测提供了重要参考。 展开更多
关键词 输电线路巡检 部件检测 SSD 特征融合
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The enhanced X-ray Timing and Polarimetry mission—eXTP 被引量:18
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作者 ShuangNan Zhang Andrea Santangelo +112 位作者 Marco Feroci YuPeng Xu FangJun lu Yong Chen Hua Feng Shu Zhang Sφren Brandt Margarita Hernanz luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J.M.in't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jörg Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen Yu Peng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino Joséluis Ga'lvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu dawei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo lu Tao luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte Jinlu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2019年第2期3-27,共25页
In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The m... In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources.The paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment. 展开更多
关键词 X-ray instrumentation X-ray polarimetry X-ray timing space mission:eXTP
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基于双应力加速寿命试验的关节轴承寿命预测与可靠性分析 被引量:15
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作者 张亚涛 邱明 +2 位作者 周大威 卢团良 庞晓旭 《润滑与密封》 CAS CSCD 北大核心 2020年第3期51-56,共6页
自润滑关节轴承寿命主要是由衬垫的磨损性能决定的,但衬垫的磨损一般是非线性的,使得寿命难以预测。采用同时改变载荷和摆频2种应力的方法进行加速寿命试验,建立以pv值、磨损量退化数据为输入参数,寿命值为输出参数的灰色神经网络预测... 自润滑关节轴承寿命主要是由衬垫的磨损性能决定的,但衬垫的磨损一般是非线性的,使得寿命难以预测。采用同时改变载荷和摆频2种应力的方法进行加速寿命试验,建立以pv值、磨损量退化数据为输入参数,寿命值为输出参数的灰色神经网络预测模型。经验证该预测模型对关节轴承寿命预测的最大误差仅为7.33%,平均误差仅为3.892%。对不同加速应力下自润滑关节轴承可靠性进行评估,结果表明,关节轴承的可靠性在L 10(可靠度为90%时的寿命)之前下降趋势缓慢,然后迅速下降,pv值越大可靠性下降越迅速;随着pv值的增大,关节轴承寿命近似呈指数下降,经验证可用逆幂率加速模型反映二者关系。 展开更多
关键词 自润滑关节轴承 双应力 灰色神经网络 寿命预测 可靠性
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‘巨峰’葡萄花穗整形方式研究 被引量:14
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作者 程大伟 陈锦永 +6 位作者 鲁会冉 顾红 张威远 张洋 郭西智 祁帅 李正阳 《果树学报》 CAS CSCD 北大核心 2018年第7期880-888,共9页
【目的】探究不同花穗整形方式对‘巨峰’葡萄果实性状和工作效率的影响,评价筛选‘巨峰’葡萄理想的整穗方式。【方法】在见花前2~3 d至见花后2~3 d分别对‘巨峰’葡萄进行留穗尖4、5、6、7、8、9 cm及剪短小分枝、去上去下留中间和去... 【目的】探究不同花穗整形方式对‘巨峰’葡萄果实性状和工作效率的影响,评价筛选‘巨峰’葡萄理想的整穗方式。【方法】在见花前2~3 d至见花后2~3 d分别对‘巨峰’葡萄进行留穗尖4、5、6、7、8、9 cm及剪短小分枝、去上去下留中间和去主穗留副穗的整穗处理。分析果实的生长指标、品质指标和工作效率,并对指标进行主成分综合评价,筛选最佳整穗方式。【结果】不同的花穗整形方式在品质及工作效率等指标上存在一定差异。综合评价结果为去主穗留副穗>留穗尖5 cm>留穗尖4 cm>留穗尖6 cm>留穗尖8 cm>留穗尖7 cm>留穗尖9 cm>去上去下留中间>剪短小分枝。结合生产实际,确定留穗尖5 cm的综合评价效果最好。【结论】留穗尖5 cm的花穗整形方式是‘巨峰’葡萄省工、提质的最佳整穗方式。 展开更多
关键词 '巨峰’葡萄 花穗整形 品质 综合评价
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术后甲状旁腺激素对甲状腺全切后永久性甲状旁腺功能减退的预测价值 被引量:12
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作者 侯大卫 徐海娥 +5 位作者 袁冰 刘建辉 王子君 鲁一兵 柳明 钱祝银 《中国肿瘤外科杂志》 CAS 2019年第5期323-326,共4页
目的探讨手术次日清晨甲状旁腺激素(PTH)水平对甲状腺全切术后永久性甲状旁腺功能减退(PHOP)的预测价值.方法选取2015年1月至2017年12月南京医科大学第二附属医院收治的行甲状腺全切加中央区淋巴结清扫的134例患者,于术前、术后及随访... 目的探讨手术次日清晨甲状旁腺激素(PTH)水平对甲状腺全切术后永久性甲状旁腺功能减退(PHOP)的预测价值.方法选取2015年1月至2017年12月南京医科大学第二附属医院收治的行甲状腺全切加中央区淋巴结清扫的134例患者,于术前、术后及随访过程中测量血钙和PTH水平,观察PHOP发生情况,比较PHOP患者术前术后的血钙和PTH水平,使用受试者操作特征(ROC)曲线评估手术次日清晨PTH水平预测甲状腺全切术后PHOP的价值.结果本研究中甲状腺全切加中央区清扫术后PHOP发生率为5.22%(7/134),7例PHOP患者术后6个月的血PTH和血钙水平均低于术前,差异有统计学意义(P<0.05).手术次日清晨PTH水平预测甲状腺全切术后PHOP的ROC曲线下面积为0.936(0.891~0.982),PTH的临界值为8 pg/ml,敏感度100.0%,特异度87.4%,阳性预测值30.4%,阴性预测值100.0%,准确率88.1%.结论术后低PTH水平与甲状腺全切术后PHOP的发生密切相关,手术次日清晨PTH水平是预测甲状腺全切术后PHOP的可靠指标. 展开更多
关键词 甲状腺全切除 甲状旁腺激素 甲状旁腺功能减退 诊断
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本期聚焦:传统聚落保护与规划研究--中国传统村落基础设施特征区划及其保护思考 被引量:11
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作者 魏成 苗凯 +1 位作者 肖大威 王璐 《现代城市研究》 CSSCI 北大核心 2017年第11期1-9,共9页
基础设施作为传统村落村民生活和生产的物质性载体,其完善与协调与否是衡量传统村落保护成效的重要标志。从分析传统村落基础设施的“适应性”、“生态性”以及“地域性”三个基本特征入手,运用与结合相关区划方法,以前三批2555个中... 基础设施作为传统村落村民生活和生产的物质性载体,其完善与协调与否是衡量传统村落保护成效的重要标志。从分析传统村落基础设施的“适应性”、“生态性”以及“地域性”三个基本特征入手,运用与结合相关区划方法,以前三批2555个中国传统村落为基础,构建了传统村薄基础设施特征区划,系统梳理了分区传统村落基础设施的典型特征,并对传统村落基础设施的保护提出了针对性的思考,以期丰富与深化传统村落保护的既有研究。 展开更多
关键词 中国传统村落 基础设施 区划 保护
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疏水型SiO2纳米颗粒稳定泡沫机理与泡沫耐温性能评价 被引量:11
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作者 李兆敏 侯大炜 +4 位作者 鹿腾 黄时祯 张克明 李晟 顾子涵 《油田化学》 CAS CSCD 北大核心 2019年第3期494-500,共7页
针对普通泡沫体系在高温油藏环境下稳定性差的问题,选用疏水纳米SiO2颗粒增强苯磺酸盐类耐温泡沫剂HY-4的高温稳定性,评价了HY-4与纳米颗粒复配前后的泡沫性能,分析了纳米颗粒的稳泡机理,评价了泡沫体系的耐温性能,对比了两种泡沫体系... 针对普通泡沫体系在高温油藏环境下稳定性差的问题,选用疏水纳米SiO2颗粒增强苯磺酸盐类耐温泡沫剂HY-4的高温稳定性,评价了HY-4与纳米颗粒复配前后的泡沫性能,分析了纳米颗粒的稳泡机理,评价了泡沫体系的耐温性能,对比了两种泡沫体系的高温封堵能力。结果表明,0.5%HY-4与1.0%疏水纳米SiO2颗粒复配体系的泡沫性能最优;在150℃之内,复配体系老化12 h后的泡沫性能明显优于HY-4泡沫体系;复配体系泡沫平均粒径小于HY-4泡沫体系,且静置1 h后泡沫粒径变化较小;在150℃下,复配泡沫体系对岩心的封堵能力优于HY-4泡沫体系,岩心产出泡沫的粒径小、球形度高、抗挤压能力强。疏水纳米SiO2颗粒可大幅增强泡沫稳定性,提高泡沫体系的高温封堵能力。 展开更多
关键词 泡沫剂 纳米SIO2颗粒 高温 稳定性 封堵能力
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单纯超声引导经颈静脉封堵治疗婴幼儿房间隔缺损 被引量:10
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作者 张大伟 潘湘斌 +8 位作者 李萍 欧阳文斌 张凤文 刘垚 王首正 赵广智 鲁雯馨 逄坤静 舒畅 《中华医学杂志》 CAS CSCD 北大核心 2019年第6期458-461,共4页
回顾性分析2017年1至12月期间在阜外医院接受单纯超声引导下经颈静脉房间隔缺损(ASD)封堵术的29例患儿的临床资料,探讨单纯超声引导下经颈静脉ASD封堵术的有效性和安全性。
关键词 房间隔缺损 间隔封堵器 超声心动描记术 婴儿
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日间宫腔镜手术中心设置及管理流程中国专家共识 被引量:9
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作者 仝佳丽 朱根海 +29 位作者 孙大为 卢丹 程玉芬 陈宏 裴丽坚 殷霞 赵卫东 张蔚 凌丹 谢熙 谭欣 朱颖军 吴晓梅 胡春艳 李华 王悦 范佳颖 贾雪梅 朱天垣 陈丽梅 郭海雁 赵绍杰 汪莎 冯素文 何晓英 池余刚 孙小丽 郎景和 隋龙 朱兰 《中华妇产科杂志》 CAS CSCD 北大核心 2022年第12期891-899,共9页
日间宫腔镜手术是指患者一日内且不过夜入、出院完成的宫腔镜手术,设置日间宫腔镜手术中心是适应现代医院发展模式的重大转变。全国有资质的各级医疗机构以不同形式和规模在开展日间宫腔镜手术,但尚缺乏统一的制度流程和规范。本共识以... 日间宫腔镜手术是指患者一日内且不过夜入、出院完成的宫腔镜手术,设置日间宫腔镜手术中心是适应现代医院发展模式的重大转变。全国有资质的各级医疗机构以不同形式和规模在开展日间宫腔镜手术,但尚缺乏统一的制度流程和规范。本共识以国际日间手术学会和中国日间手术合作联盟发布的相关文献为参考,结合中国开展日间手术成熟的医疗机构的制度流程,从日间宫腔镜手术中心的设置、管理制度、管理流程到质量控制以及并发症的处理及转运给予了共识性建议,同时,对医疗、护理和麻醉三个维度的评估和相关问题处理制定了规范化流程。 展开更多
关键词 宫腔镜手术 日间手术 规范化流程 医疗机构 制度流程 合作联盟 共识性 管理流程
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The Low Energy X-ray telescope (LE) onboard the Insight-HXMT astronomy satellite 被引量:10
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作者 Yong Chen WeiWei Cui +24 位作者 Wei Li Juan Wang YuPeng Xu FangJun lul YuSa Wang TianXiang Chen dawei Han Wei Hu Yi Zhang Jia Huo YanJi Yang MaoShun Li Bo lu ZiLiang Zhang TiPei Li ShuangNan Zhang ShaoLin Xiong Shu Zhang RongFeng Xue XiaoFan Zhao Yue Zhu YuXuan Zhu HongWei Liu YiJung Yang Fan Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第4期49-61,共13页
The Low Energy X-ray telescope(LE) is one of the three main instruments of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT). It is equipped with Swept Charge Device(SCD) sensor arrays with a total geometrical... The Low Energy X-ray telescope(LE) is one of the three main instruments of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT). It is equipped with Swept Charge Device(SCD) sensor arrays with a total geometrical area of 384 cm^2 and an energy band from 0.7 to 13 ke V. In order to evaluate the particle induced X-ray background and the cosmic X-ray background simultaneously, LE adopts collimators to define four types of Field Of Views(FOVs), i.e., 1.6°×6°, 4°×6°, 50°-60°×2°-6 oand the blocked ones which block the X-ray by an aluminum cover. LE is constituted of three detector boxes(LEDs) and an electric control box(LEB) and achieves a good energy resolution of 140 e V@5.9 ke V, an excellent time resolution of 0.98 ms, as well as an extremely low pileup(<1%@18000 cts/s). Detailed performance tests and calibration on the ground have been performed,including energy-channel relation, energy response, detection efficiency and time response. 展开更多
关键词 LE X-ray telescope SCD COLLIMATORS
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绕管式换热器管板的有限元应力分析与结构优化 被引量:10
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作者 陈杰 纪博文 +3 位作者 庄大伟 鹿来运 张晓慧 丁国良 《化工学报》 EI CAS CSCD 北大核心 2018年第A02期128-134,共7页
绕管式换热器广泛应用于大型天然气液化装置,而管板是绕管式换热器的重要组成部件。由于管板处于管程、壳程交界处且布有密集的孔洞,降低了结构强度,使其成为LNG绕管式换热器的相对薄弱部位。利用Ansys有限元计算软件,对LNG绕管式换热... 绕管式换热器广泛应用于大型天然气液化装置,而管板是绕管式换热器的重要组成部件。由于管板处于管程、壳程交界处且布有密集的孔洞,降低了结构强度,使其成为LNG绕管式换热器的相对薄弱部位。利用Ansys有限元计算软件,对LNG绕管式换热器管板及其相连的管箱、换热器壳体进行整体建模和多工况下的有限元应力分析,并根据JB4732—1995进行强度校核。计算结果显示,换热器壳体对管箱短节部分的应力有较大影响;实例中换热器外壳的拉伸作用导致短节内侧局部薄膜应力过大,超出许用强度。增加短节厚度可以有效提高管箱强度;通过将原短节厚度由45 mm增加到57.5 mm,解决了局部薄膜应力过大的问题。 展开更多
关键词 管板 绕管式换热器 有限元 应力分析 固体力学 设计 优化
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基于三维探地雷达的沥青路面层间接触状态智能诊断技术 被引量:8
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作者 王大为 吕浩天 +2 位作者 汤伏蛟 叶呈森 刘鹏飞 《北京工业大学学报》 CAS CSCD 北大核心 2022年第6期572-579,共8页
层间接触状态对路面结构力学性能和使用寿命有重要影响,为了研究沥青路面结构在车辆荷载作用下层间结合情况,以某改扩建沥青路面层间接触状态检测工程为依托,基于三维探地雷达无损检测技术提出了沥青路面层间接触状态评价方法,并对该改... 层间接触状态对路面结构力学性能和使用寿命有重要影响,为了研究沥青路面结构在车辆荷载作用下层间结合情况,以某改扩建沥青路面层间接触状态检测工程为依托,基于三维探地雷达无损检测技术提出了沥青路面层间接触状态评价方法,并对该改扩建工程沥青路面的层间结合情况以及层间接触状态的衰变规律进行了分析.结果表明:层间界面反射波振幅峰值大小可较好描述沥青路面层间接触状态;各车道层间界面振幅服从对数正态分布;振幅峰值小于1.0 mm(层间接触良好)的区域占整体区域的70%左右;振幅峰值大于2.0 mm(层间接触较差)的区域占不足3%.检测结果及数据分析表明,检测路段行车道和超车道的层间结合情况较应急车道好,可为沥青路面层间接触状态评价提供理论及技术支撑. 展开更多
关键词 探地雷达(GPR) 沥青路面 无损检测 力学性能 层间接触状态 反射振幅
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