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Structural Characteristics of the Basement beneath Qiangtang Basin in Qinghai-Tibet Plateau: Results of Interaction Interpretation from Seismic Reflection/Refraction Data

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 358-377页

作者： LI Qiusheng GAO Rui FENG Shaoying LU Zhanwu HOU Hesheng guan ye LI Pengwu WANG Haiyan ye Zhuo XIONG Xiaosong LIU Jinkai HE Rizheng Institute of Geology CAGS Earthprobe and Geodynamics Open Laboratory of CAGS The Geophysical Exploration center CEA East China Petroleum Geology Bureau China Petrochemical Corporation

The studies on configuration, character/property of the basement of Qiangtang basin is helpful for evaluating petroleum and nature gas resources as well as understanding the basin evolvement. Recently a moderate to high-grade metamorphic gneiss rock was found underlying beneath very low metamorphic Ordovician strata in Mayer Kangri to the north of the central uplift. That fact actually proved existence of the crystalline basement just the distribution and structures of pre-Paleozoic crystalline basement still remain puzzle. In recent years a number of active sources deep seismic profiling, to aim at lithospheric structure of northern Tibet and petroleum resources of the Qiangtang basin, had been conducted that make it possible to image the structure of the basement of the Qiangtang. Near vertical reflection profiles, included those acquired previously and those during 2004 to 2008, have been utilized in this study. By through the interaction process and interpretation between the reflection profiles and the wide-angle profile, a model with the detailed structure and velocity distribution from surface to the depth of 20 km of Qiangtang basin has been *** on the results and discussions of this study, the preliminary conclusions are as follows：（1） The velocity structure section （~20 kin） that is interactively constrained by the refraction and reflection seismic data reveals that the sedimentary stratum gently lie until 10 km in the south Qiangtang basin. （2） The basement consists of fold basement （the upper） and crystalline basement （the lower）.The fold basement buried at the average depth of 6 km with a velocity of 5.2-5.8 km/s. The shallowest appear at range of the central uplift. The crystalline basement is underlying beneath the fold basement at the average depth of 10 km with a velocity of 5.9-6.0 km/s except near Bangong-Nujiang suture. （3） The high-velocity body at the depth range of 3-6 km of the central uplift is considered as a fragment of the cryst

关键词： seismic reflection seismic refraction basement structure Qiangtang basin Qinghai-TibetPlateau

循环荷载下水泥土桩复合单元体变形特性及其地基长期沉降计算方法

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中国公路学报 2022年第11期35卷 21-29页

作者：张振郑文强叶观宝陈勇同济大学土木工程学院地下建筑与工程系上海200092 同济大学岩土及地下工程教育部重点实验室上海200092 上海勘察设计研究院(集团)有限公司上海200093

对于软土地区的路基工程,若路基处理不当,在长期交通荷载作用下,容易导致服役期路面开裂、不均匀沉降等问题。水泥土搅拌桩法是软土地区最常用的路基加固方法之一。研究循环荷载下水泥土桩复合地基的变形特性,对于指导交通荷载下软土地... 详细信息

对于软土地区的路基工程,若路基处理不当,在长期交通荷载作用下,容易导致服役期路面开裂、不均匀沉降等问题。水泥土搅拌桩法是软土地区最常用的路基加固方法之一。研究循环荷载下水泥土桩复合地基的变形特性,对于指导交通荷载下软土地基长期沉降控制具有重要意义。然而,现有研究主要集中在软土和水泥土单一介质,对于水泥土桩复合体的研究较少。通过开展水泥土桩复合单元体大型动三轴试验,分析围压、静偏应力和置换率等因素对水泥土桩复合体累积塑性应变的影响。研究结果表明:循环荷载下水泥土桩复合体累积塑性显著小于软土,且应变随围压、动应力比及静偏应力的增大而增大,随置换率的增大而减小;静偏应力的增加会导致复合单元体临界动应力比的减小。基于试验结果,建立了水泥土桩复合体长期沉降计算方法。结合现代有轨电车算例,分析交通荷载作用下软土路基以及经水泥土桩法处理后的路基长期沉降结果。计算结果表明,采用水泥土桩法可有效减小软土路基长期沉降。

关键词：道路工程长期沉降大型动三轴试验水泥土桩复合体计算方法分级循环加载

Fractional anisotropy for assessment of white matter tracts injury in methylmalonic acidemia

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Chinese Medical Journal 2009年第8期122卷 945-949页

作者： GAO Yu guan Wen-ye WANG Jiang ZHANG Yu-zhen LI Yu-hua HAN Lian-shu Department of Radiology Xinhua Hospital Medical School of Shanghai Jiao Tong University Shanghai 200092 China Neuroscience Research Group School of Electrical and Automation Engineering Tianjin University Tianjin 300072 China Department of Pediatric Internal Medicine Xinhua Hospital Medical School of Shanghai Jiao Tong University Shanghai 200092 China

Background Methylmalonic acidemia （MMA） is a multifactorial autosomal recessive inborn error of organic acid metabolism, often presenting with neurological symptoms. As neurological disorders are often related to white matter injury, diffusion tensor imaging （DTI） is an excellent tool for assessment of white matter injury and possibly for diagnosing this disorder. Methods We retrospectively analyzed DTI images of 12 patients with MMA （7 males, 5 females, age range： 7-12 months, mean age： 9.25±1.70 months） with negative MRI findings. And another 12 age-matched and gender-matched infants were enrolled as control subjects. Fractional anisotropy （FA） of different white matter tracts of the brain was measured in both groups. Results For patients with negative MRI findings, compared with healthy infants, a statistically significant reduction in DTI FA value of the frontal white matter, temporal white matter, and occipital white matter was observed （P〈0.01）. Conclusions In addition to conventional TlW and T2W MR Image, Brain DTI presents a useful, sensitive and complementary tool for the assessment of brain damage in patients with MMA.

关键词： diffusion tensor imaging magnetic resonance imaging fractional anisotropy methylmalonic acidemia children

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复杂人机交互场景下的指势用户对象识别

电子学报 2014年第11期42卷 2135-2141页

作者：管业鹏上海大学通信与信息工程学院上海200072 新型显示技术及应用集成教育部重点实验室上海200072

采用指势进行人机交互,可充分发挥人类日常技能,摆脱常规输入设备束缚.实现自然的指势人机交互的关键是,如何从复杂的人机交互场景中有效提取指势用户对象,提出了基于时/空运动特征的指势用户对象识别新方法.基于多尺度小波变换在时/空... 详细信息

采用指势进行人机交互,可充分发挥人类日常技能,摆脱常规输入设备束缚.实现自然的指势人机交互的关键是,如何从复杂的人机交互场景中有效提取指势用户对象,提出了基于时/空运动特征的指势用户对象识别新方法.基于多尺度小波变换在时/空域所具有的优异局部化特性,从复杂场景中提取前景运动对象,克服环境条件约束以及动态环境变化及先验假设等不足;基于多尺度小波变换的梯度积分图方法,获取稳定可靠的指势手部HOG特征,采用机器学习方法,对上述特征向量分类,并基于指势手与指势用户对象的空间关联性识别指势用户对象.通过实验对比,结果表明本文方法有效、可行.

关键词：人机交互模式识别时/空特征对象分割特征提取

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基于立体视觉的非穿戴指势识别

控制理论与应用 2009年第12期26卷 1345-1350页

作者：管业鹏上海大学通信与信息工程学院上海200072 新型显示技术及应用集成教育部重点实验室上海200072

基于彩色图像中红、绿、蓝3分量强度在阴影区域存在差异,根据小波变换在时域和空域均具有优异的局部化特征,结合背景差分,进行小波多尺度变换,提取视频指势对象,所提方法不需场景学习与训练、手工校正及先验假设等信息,可克服动态场景... 详细信息

基于彩色图像中红、绿、蓝3分量强度在阴影区域存在差异,根据小波变换在时域和空域均具有优异的局部化特征,结合背景差分,进行小波多尺度变换,提取视频指势对象,所提方法不需场景学习与训练、手工校正及先验假设等信息,可克服动态场景变化、阴影、噪声干扰等影响,具有强的鲁棒性.基于人类生物结构特征,采用不易遮挡和不受人脸朝向、姿态、光照变化等影响的头顶特征代替人眼特征,保证了人机交互活动的自由性和自然性,且提高了人机交互的时效性.融合手指尖特征和手臂中心轴线及其外极线的多几何约束策略,采用求解反对应方法,确保手指特征匹配对应的正确性.通过实验验证,证实了上述方法有效、可行,可应用于实时、非穿戴的自然指势视觉3维人机交互中.

关键词：指势识别人机交互非穿戴多尺度小波变换

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基于多模态视觉特征的自然人机交互

电子学报 2013年第11期41卷 2223-2229页

作者：管业鹏上海大学通信与信息工程学院上海200072 新型显示技术及应用集成教育部重点实验室上海200072

针对目前人机交互中存在的问题与不足,提出了一种基于多模态视觉特征的人机交互新方法.采用二维Gabor小波提取全局人脸朝向视觉特征,克服人脸显著特征提取困难,以及不同人脸朝向特征区分的难度性;基于人脸几何分布特征,快速定位人眼中心... 详细信息

针对目前人机交互中存在的问题与不足,提出了一种基于多模态视觉特征的人机交互新方法.采用二维Gabor小波提取全局人脸朝向视觉特征,克服人脸显著特征提取困难,以及不同人脸朝向特征区分的难度性;基于人脸几何分布特征,快速定位人眼中心,无需考虑人脸图像分辨率和人眼闭合及其配戴情况;通过对视觉特征的重要性评价,选取分类特性显著的多模态视觉特征进行机器学习与训练,确定用户所指目标,实现非穿戴自然人机交互,用户无需佩戴任何标记,且其活动不受约束,便于充分发挥其日常技能.通过实验对比,验证了文中所提方法有效、可行,可应用于实时非穿戴自然人机交互中.

关键词：人机交互多模态视觉特征非穿戴机器学习

Deep Background of Wenchuan Earthquake and the Upper Crust Structure beneath the Longmen Shan and Adjacent Areas

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 733-739页

作者： LI Qiusheng GAO Rui WANG Haiyan ZHANG Jisheng LU Zhanwu LI Pengwu guan ye HE Rizheng Lithosphere Research Centre Institute of Geology CAGS Beijing 100037 China Eearthprobe and Geodynamics Open Laboratory of CAGS Beijing 100037 China

By analyzing the deep seismic sounding profiles across the Longmen Shan, this paper focuses on the study of the relationship between the upper crust structure of the Longmen Shan area and the Wenchuan earthquake. The Longmen Shan thrust belt marks not only the topographical change, but also the lateral velocity variation between the eastern Tibetan Plateau and the Sichuan Basin. A low-velocity layer has consistently been found in the crust beneath the eastern edge of the Tibetan Plateau, and ends beneath the western Sichuan Basin. The low-velocity layer at a depth of -20 km beneath the eastern edge of the Tibetan Plateau has been considered as the deep condition for favoring energy accumulation that formed the great Wenchuan earthquake.

关键词： the Longmen Shan deep seismic sounding profile upper crust structure Wenchuan Earthquake

Relationship between Crustal 3D Density Structure and the Earthquakes in the Longmenshan Range and Adjacent Areas

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 740-745页

作者： ZHANG Jisheng GAO Rui ZENG Lingsen LI Qiusheng guan ye HE Rizheng WANG Haiyan LU Zhanwu Institute of Geology Chinese Academy of Geological SciencesEearthprobe and Geodynamics Open Laboratory of CAGS Beijing 100037 China

This paper presents the 3D density structure of crust in the Longmenshan range and adjacent areas, with constraints from seismic and density data. The density structure of crust shows that the immense boundary plane of density distribution in relation to the Longmeshan fault belt is extended downward to -80 km deep. This density boundary plane dips towards the northwest and crosses the Moho. With the proximity to the Longmenshan fault belt, it has a larger magnitude of undulation in the upper and middle crust levels. Density changes abruptly across Longmeshan fault belt. Seismic data show that most of the earthquakes in the Longmenshan area after the 2008 Ms8.0 Wenchuan Earthquake occurred within the upper to middle crust. These earthquakes are clearly distributed in the uplifted region of the basement. A few of them occurs in the transitional zone between the uplifted and subsided areas. But most of the earthquakes distributes in transitional zone from subsided to uplifted areas in the upper and middle crust where relatively large density changes occurr The 3D density structure of crust in the Longmenshan and adjacent areas can thus help us to understand the pattern of overthrusting from the standpoint of deep crust and where the earthquakes occurred.

关键词： Wenchuan earthquake Longmenshan fault zone gravity anomaly density structure of crust

浙江省2008~2018年人为源氨排放清单及分布特征

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环境科学 2022年第10期43卷 4380-4391页

作者：方利江杨一群叶观琼舟山市生态环境保护技术中心舟山316000 浙江大学海洋学院舟山316000

以浙江省为研究区域,通过收集11个地级市各类氨排放的活动水平数据,采用排放因子法建立了2008~2018年浙江省人为源氨排放清单,并利用ArcGIS进行1 km×1 km空间网格分配.结果表明,2008~2018年浙江省人为源氨排放量总体呈现下降趋势,年均... 详细信息

以浙江省为研究区域,通过收集11个地级市各类氨排放的活动水平数据,采用排放因子法建立了2008~2018年浙江省人为源氨排放清单,并利用ArcGIS进行1 km×1 km空间网格分配.结果表明,2008~2018年浙江省人为源氨排放量总体呈现下降趋势,年均下降率约3.97%;2018年浙江省氨排放量为108.52 kt,其中农业源为90.02 kt,非农业源为18.50 kt,排放强度为1.03 t·km^(-2);杭州市、嘉兴市和温州市的氨排放量高于其他城市,分别占全省总量的14.72%、 11.86%和11.80%;空间分布特征显示,氨排放主要分布在浙江省北部区域,呈现出“北高南低”的排放趋势;不确定性分析表明,氨排放量模拟平均值为108.37 kt,在95%置信区间的不确定度范围为-5.40%~5.60%.

关键词：浙江省人为源氨排放清单年际变化空间分布特征不确定性分析