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CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan
《机械工程前沿(英文)》 2006年 第1卷 第2期 页码 242-247 doi: 10.1007/s11465-006-0008-0
关键词: multiphase unequal interval capacitance tomography pattern sensitivity
Zhonghua Sun
《医学前沿(英文)》 2011年 第5卷 第3期 页码 254-270 doi: 10.1007/s11684-011-0153-7
关键词: cardiovascular disease multislice computed tomography three-dimensional reconstruction diagnosis visualization
珊瑚岛礁环境噪声成像 Article
夏少红, 张昌榕, 曹敬贺
《工程(英文)》 2023年 第25卷 第6期 页码 182-193 doi: 10.1016/j.eng.2021.09.022
As valuable land in the ocean, coral islands are not only important bases for making use of marine resources and protecting marine rights and interests, but also important for breakthrough research in many fields of earth science. Hence, the economical and efficient determination of the underground structure of coral islands has become significant in coral island engineering geology, but remains challenging for traditional marine geophysical prospecting and drilling methods. While ambient noise tomography with dense arrays has been widely used in continental regions, its applicability to coral islands remains undetermined. In this study, based on the data recorded by a dense array on an isolated coral island in the South China Sea, we analyzed the ambient noise characteristics and obtained a 3D subsurface structure of the coral island using ambient noise tomography. We made the following findings: ① The ambient noise frequencies can be roughly categorized into three levels: < 1, 1–5, and > 5 Hz. The spectral characteristics of the noise below 5 Hz were consistent at different stations, but there were significant differences in the characteristics of the noise above 5 Hz. ② For ambient noise frequencies below 5 Hz, cross-correlation functions with high quality could be obtained with only 24 h of waveform data. However, it was difficult to extract meaningful cross-correlation functions for ambient noise frequencies above 5 Hz. ③ The S-wave velocity in the coral island was higher toward the sea and lower toward the lagoon, which was consistent with the high degree of cementation of the outer reef flat stratum on the seaward side. ④ There were two low-velocity horizons at 25–75 and 200–300 m, which were in good agreement with the high-porosity horizons that were revealed by drilling core samples, reflecting the weathering history of the reef. Our research demonstrates that ambient noise tomography is a potentially economical, efficient, and environmentally friendly method for the geological prospecting of coral reefs.
关键词: Coral island Ambient noise tomography Engineering geology South China Sea
Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA
《结构与土木工程前沿(英文)》 2019年 第13卷 第3期 页码 640-652 doi: 10.1007/s11709-018-0502-6
关键词: mechanical property municipal solid waste incineration residues coal fly ash unconfined compression test image analysis X-Ray Computed Tomography scanners
Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG
《医学前沿(英文)》 2009年 第3卷 第2期 页码 230-235 doi: 10.1007/s11684-009-0023-8
关键词: computed tomography angiography computed tomography perfusion
Fatigue of asphalt binder, mastic and mixture at low temperature
Dong WANG, Linbing WANG, Guoqing ZHOU
《结构与土木工程前沿(英文)》 2012年 第6卷 第2期 页码 166-175 doi: 10.1007/s11709-012-0157-7
关键词: fatigue asphalt mixture asphalt binder mastic finite element method (FEM) X-ray tomography
李宝清,陆德仁,王渭源
《中国工程科学》 2000年 第2卷 第2期 页码 36-40
文章首次报道了一种基于面积可变电容结构的微机械加速度传感器。质量块呈栅状结构,由悬臂梁支撑。两组交叉放置的定电极位于质量块的正下方。在惯性力的作用下,质量块呈平行于衬底水平移动,引起由质量块的栅与定电极的叉指构成的差分电容变化。通过测量差分电容的变化,可以得到加速信号的大小。理论分析表明加速度响应信号随面积呈线性变化,而与质量块及定电极的间距无关。加速度传感器的制作采用了基于金属电镀的准LIGA技术,设计量程为20m/s2。测量结果表明,加速度传感器量程为20m/s2,灵敏度为58.1mV/(m·s-2),非线性为4%FS。讨论了器件线性度不够理想的原因。
何季麟
《中国工程科学》 2001年 第3卷 第12期 页码 85-89
论述了国内外电容器级高压钽粉、中压钽粉、高比容钽粉的生产工艺发展过程。在钽粉生产工艺发展过程中,各种先进的装备被应用,各钽粉生产厂家围绕着钽粉比容的提高,杂质含量的降低,物理性能的优化等综合性能的改善,不断开发出新工艺、新技术,使钽粉适应并推动着钽电容器的发展。
基于多声源波速结构成像的岩体异常区域超前辨识方法 Article
董陇军, 裴重伟, 谢鑫, 张义涵, 闫先航
《工程(英文)》 2023年 第22卷 第3期 页码 191-200 doi: 10.1016/j.eng.2022.05.016
异常区域超前辨识对于预防地下岩土工程灾害具有重要作用。为了满足地下工程高精度探测的需求,本文提出一种层析成像方法以辨识复杂岩体结构中的异常区域,结合了走时层析、阻尼最小二乘法和高斯滤波等技术。该方法克服了空洞区域辨识中速度差限制,减轻了迭代中孤立速度突变所带来的影响。开展了数值和室内实验,量化评估最短路径法(shortest-path method, SPM)、动态最短路径法(dynamic shortest-path method, DSPM)和快速扫描法(fast sweeping method, FSM)等正演模拟的识别精度和计算效率。结果表明,在数值和室内实验中DSPM和FSM均能清晰地辨识出异常区域。陕西震奥矿山现场应用结果证明了该方法可利用矿山开采中爆破、微震等多类声源对矿山内部未知结构进行波速场成像。本研究不仅实现了走时层析成像方法在异常区域识别中的应用,而且为地下岩土工程中潜在风险源的探测提供了新的思路。
《化学科学与工程前沿(英文)》 2023年 第17卷 第12期 页码 2014-2024 doi: 10.1007/s11705-023-2346-4
关键词: capacitance deionization porous carbon B/N co-doping heavy metal ions water purification
Low-dose CT for lung cancer screening: opportunities and challenges
null
《医学前沿(英文)》 2018年 第12卷 第1期 页码 116-121 doi: 10.1007/s11684-017-0600-1
Lung cancer is among the most frequently diagnosed cancers worldwide and the leading cause of cancer death in both males and females. Screening for lung cancer coupled with earlier intervention has long been studied as an approach to mortality reduction. However, minimal progress was achieved until recently, when low-dose spiral computed tomography (LDCT) screening demonstrated a 20% reduction in mortality from lung cancer in a randomized controlled trial (RCT), the National Lung Screening Trial, from the United States. On the basis of this finding, LDCT has been recommended for lung cancer screening in high-risk populations by several clinical guidelines. However, results from the following independent RCTs in Europe failed to show consistent conclusions. In addition, intractable problems gradually emerged with the progress of LDCT screening. This paper summarizes and discusses the main observations and challenges of LDCT screening for lung cancer. Before spreading implementation of LDCT screening, challenges, including high false-positive rates, overdiagnosis, enormous costs, and radiation risk, must be addressed. Complementary biomarkers and technical improvement are expected in the field of lung cancer screening in the near future.
关键词: lung cancer low-dose computerized tomography early detection opportunities challenges
《医学前沿(英文)》 2022年 第16卷 第3期 页码 429-441 doi: 10.1007/s11684-021-0842-9
关键词: ischemic stroke microenvironment induced pluripotent stem cells (iPSCs) positron emission tomography (PET) quantitative proteomics
F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma
《医学前沿(英文)》 2021年 第15卷 第6期 页码 913-921 doi: 10.1007/s11684-021-0874-1
关键词: hypothalamic hamartoma gelastic seizure fluorodeoxyglucose-positron emission tomography voxel-based morphometry
Observation of premixed flame fronts by laser tomography
MU Kejin, WANG Yue, LEI Yu, ZHANG Zhedian, NIE Chaoqun, XIAO Yunhan
《能源前沿(英文)》 2008年 第2卷 第4期 页码 427-432 doi: 10.1007/s11708-008-0069-3
关键词: combustion tomography apparatus processing exploitation propagation
Tang-tang GUO,Xing-liang LIU,Shi-qiang HAO,Chi ZHANG,Xiang-ning HE
《信息与电子工程前沿(英文)》 2015年 第16卷 第3期 页码 249-258 doi: 10.1631/FITEE.1400185
关键词: Dielectric barrier discharge Rectifier-compensated first harmonic approximation Parasitic capacitance Power converter design
标题 作者 时间 类型 操作
novel method of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitancetomography system
CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan
期刊论文
Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations
Zhonghua Sun
期刊论文
properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography
Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA
期刊论文
Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic helical scan on 16 MDCT
Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG
期刊论文
Fatigue of asphalt binder, mastic and mixture at low temperature
Dong WANG, Linbing WANG, Guoqing ZHOU
期刊论文
Boron and nitrogen co-doped porous carbon derived from sodium alginate enhanced capacitive deionization for water purification
期刊论文
Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic stroke
期刊论文
Observation of premixed flame fronts by laser tomography
MU Kejin, WANG Yue, LEI Yu, ZHANG Zhedian, NIE Chaoqun, XIAO Yunhan
期刊论文