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扎染工艺下铜鼓纹样方巾盲盒设计
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作者 李嘉彪 刘爽 《湖南包装》 2024年第1期194-197,共4页
针对当今盲盒设计形式乏味单一等问题,文章基于扎染工艺,将广西铜鼓纹样融合在盲盒设计中,先分别从文化价值和美学价值两个方面具体分析铜鼓纹样在方巾盲盒设计中的应用价值,然后通过对铜鼓纹样提取、解构及重组的方式对铜鼓纹样方巾进... 针对当今盲盒设计形式乏味单一等问题,文章基于扎染工艺,将广西铜鼓纹样融合在盲盒设计中,先分别从文化价值和美学价值两个方面具体分析铜鼓纹样在方巾盲盒设计中的应用价值,然后通过对铜鼓纹样提取、解构及重组的方式对铜鼓纹样方巾进行多样化图案设计,最终采用扎染工艺进行铜鼓方巾的盲盒设计,以增强盲盒设计的民族性和多样性,为盲盒设计注入新的生命力。 展开更多
关键词 扎染 方巾 铜鼓纹样 盲盒
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Seismic phases from the Moho and its implication on the ultraslow spreading ridge 被引量:5
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作者 ZHANG Jiazheng ZHAO Minghui +2 位作者 QIU Xuelin li jiabiao RUAN Aiguo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期75-86,共12页
The Moho interface provides critical evidence for crustal thickness and the mode of oceanic crust accretion. The seismic Moho interface has not been identified yet at the magma-rich segments (46°-52°E) of ... The Moho interface provides critical evidence for crustal thickness and the mode of oceanic crust accretion. The seismic Moho interface has not been identified yet at the magma-rich segments (46°-52°E) of the ultra- slow spreading Southwestern Indian Ridge (SWIR). This paper firstly deduces the characteristics and do- mains of seismic phases based on a theoretical oceanic crust model. Then, topographic correction is carried out for the OBS record sections along Profile Y3Y4 using the latest OBS data acquired from the detailed 3D seismic survey at the SWIR in 2010. Seismic phases are identified and analyzed, especially for the reflected and refracted seismic phases from the Moho. A 2D crustal model is finally established using the ray tracing and travel-time simulation method. The presence of reflected seismic phases at Segment 28 shows that the crustal rocks have been separated from the mantle by cooling and the Moho interface has already formed at zero age. The 2D seismic velocity structure across the axis of Segment 28 indicates that detachment faults play a key role during the processes of asymmetric oceanic crust accretion. 展开更多
关键词 Moho interface seismic phases ultra-slow spreading ridge 2D crustal structure SouthwesternIndian Ridge (SWIR)
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Methods and procedures to determine the outer limits of the continental shelf beyond 200 nautical miles
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作者 WU Ziyin li jiabiao +3 位作者 JIN Xianglong FANG Yinxia SHANG Jihong li Shoujun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期126-132,共7页
This paper establishes techniques and methods to determine a variety of boundaries associated with 200 nautical miles beyond the continental shelf. The methods, based on topography, slope and second-deriv- ative profi... This paper establishes techniques and methods to determine a variety of boundaries associated with 200 nautical miles beyond the continental shelf. The methods, based on topography, slope and second-deriv- ative profile integrated analysis, are now able to identify automatically the foot of the continental slope (FOS). By analyzing the sedimentary profile, the points of 1% sediment thickness are recognized. Through the intersection, cut, deletion and mergence calculation of the extrapolated data set of fLxed-point series, the method succeeds in generating automatically the extrapolated boundaries, including the FOS+60 M line, the 350 M line, and the 2500 m+100 M line. In addition, based on the automatic analysis of the topographic profile, it can be applied to determine rapidly the points of maximum water depth. Taking the northern Okinawa Trough (OT) as an example, these methods are used to calculate and examine the boundaries in- cluded in the Submission by the People's Republic of China Concerning the Outer Limits of the Continental Shelf beyond 200 Nautical miles in Part of the East China Sea (ECS); the boundaries thus derived have a solid scientific and rational basis. 展开更多
关键词 200 nautical miles continental shelf DEMARCATION METHODOLOGY Okinawa Trough
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幂函数正弦柔性铰链设计与分析
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作者 李佳彪 赵阳 +3 位作者 吴清文 母德强 刘昌儒 胡金鑫 《机械传动》 北大核心 2023年第7期77-83,共7页
提出了一种新型幂函数正弦柔性铰链,利用卡氏第二定理推导了柔性铰链的柔度与转动精度计算公式,并取不同参数值对柔度和转动精度进行了有限元仿真分析和理论值计算,相对误差在10%以内,验证了计算公式的正确性;分析了柔性铰链的曲线方程... 提出了一种新型幂函数正弦柔性铰链,利用卡氏第二定理推导了柔性铰链的柔度与转动精度计算公式,并取不同参数值对柔度和转动精度进行了有限元仿真分析和理论值计算,相对误差在10%以内,验证了计算公式的正确性;分析了柔性铰链的曲线方程参数对铰链性能的影响。结果表明,最小厚度对柔性铰链的性能影响最大。此外,将椭圆、双曲线与新型铰链进行了对比。结果表明,椭圆柔性铰链的柔度最大,但是转动精度最小;双曲线柔性铰链的转动精度最大,但是柔度最小。通过引入柔度精度比β,分析对比得知,在相同L的情况下,改变d,幂函数正弦柔性铰链的β值分别比椭圆和双曲线柔性铰链平均提高了2.68倍和1.237倍;在相同d的情况下,改变L,幂函数正弦柔性铰链的β值分别比椭圆和双曲线柔性铰链平均提高了2.60倍和1.18倍。表明幂函数正弦柔性铰链的综合性能更有优势。 展开更多
关键词 柔性铰链 幂函数正弦 柔度 转动精度 有限元分析
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利用深层卷积神经网络实现地形辅助的多波束海底底质分类 被引量:8
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作者 阳凡林 朱正任 +3 位作者 李家彪 冯成凯 邢喆 吴自银 《测绘学报》 EI CSCD 北大核心 2021年第1期71-84,共14页
海底底质分类对于海洋资源开发与利用、海洋科学研究等多方面具有重要意义。目前,多波束探测是实现大范围海底底质分类的有效手段之一,通常基于多波束反向散射强度提取角度响应(AR)特征及反向散射图像特征进行底质分类。由于特征来源较... 海底底质分类对于海洋资源开发与利用、海洋科学研究等多方面具有重要意义。目前,多波束探测是实现大范围海底底质分类的有效手段之一,通常基于多波束反向散射强度提取角度响应(AR)特征及反向散射图像特征进行底质分类。由于特征来源较单一,分类器结构简单,往往分类精度不高。为此,本文提出了一种基于深层卷积神经网络(CNN)的多波束海底底质分类方法。除反向散射强度特征外,还利用地形特征,将特征向量转换为波形图,再输入卷积神经网络进行训练和分类。试验对比不同特征组合以及BP网络、支持向量机(SVM)、K近邻(KNN)、随机森林(RF)4种常规分类器,本文模型算法总体分类精度达到94.86%,Kappa系数为0.93,精度具有明显优势,效率也比较高。表明该方法有效利用两种数据类型所蕴含的海底底质信息,充分发挥卷积神经网络权值共享、高效率等特点,实现高分辨率海底底质分类,可对海底底质分类研究提供参考。 展开更多
关键词 多波束 反向散射图像 角度响应 底质分类 卷积神经网络
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南海大洋钻探及海洋地质与地球物理前沿研究新突破 被引量:40
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作者 林间 李家彪 +9 位作者 徐义刚 孙珍 夏少红 黄小龙 解习农 李春峰 丁巍伟 周志远 张帆 罗怡鸣 《海洋学报》 CAS CSCD 北大核心 2019年第10期125-140,共16页
南海是西太平洋地区规模最大且具有代表性的边缘海盆地之一。经过近几十年的研究积累,尤其是通过实施5个国际大洋钻探航次(1999–2018年)与国家自然科学基金委“南海深海过程演变”重大研究计划(2011–2019年),我国科学家获得了大量宝... 南海是西太平洋地区规模最大且具有代表性的边缘海盆地之一。经过近几十年的研究积累,尤其是通过实施5个国际大洋钻探航次(1999–2018年)与国家自然科学基金委“南海深海过程演变”重大研究计划(2011–2019年),我国科学家获得了大量宝贵的第一手资料,取得了一系列创新进展与重大突破,标志着南海海洋地质与地球物理研究正走向国际前沿。重要研究成果包括:(1)新提出南海是“板缘张裂”盆地,与经典的大西洋型陆缘模式不同;(2)大洋钻探首次获取了基底玄武岩样品,结合中国在南海首次深拖地磁测量实验,精确测定了南海海盆玄武岩年龄,揭示南海海盆从东向西分段扩张;(3)大洋钻探结果发现南海陆缘岩石圈减薄之初岩浆迅速出现,未发现缓慢破裂造成的蛇纹岩出露;(4)发现南海扩张结束后仍存在大量岩浆活动,可能受控于多种构造与地幔因素;(5)地球化学证据与地球动力学模拟都显示南海岩浆的形成受到周边俯冲带的影响。目前我国的海洋地球科学正在进入崭新的发展阶段,有望以南海为基点,开始拓展到周边大洋,通过主导大型研究计划以及建设我国大洋钻探平台,以提升我国在南海、西太平洋与印度洋海洋地质科学研究的实质性影响力与引领地位。 展开更多
关键词 南海 国际大洋钻探 海洋地质与地球物理 构造与岩浆活动 大陆岩石圈张裂 海底扩张
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CUBE曲面滤波参数联合优选关键技术及应用 被引量:15
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作者 赵荻能 吴自银 +5 位作者 李家彪 周洁琼 张田升 刘洋 朱超 余威 《测绘学报》 EI CSCD 北大核心 2019年第2期245-255,共11页
CUBE(combined uncertainty and bathymetry estimator)算法是国际上主流的多波束测深异常值自动探测与处理算法,在国内外被广泛应用,但对其核心算法和参数知之甚少,不利于该项技术的国产化。本文详细阐述了CUBE算法的基本原理、数学模... CUBE(combined uncertainty and bathymetry estimator)算法是国际上主流的多波束测深异常值自动探测与处理算法,在国内外被广泛应用,但对其核心算法和参数知之甚少,不利于该项技术的国产化。本文详细阐述了CUBE算法的基本原理、数学模型、关键参数和处理步骤,进而建立了CUBE曲面滤波参数联合优选方法。通过选取典型地形区、参数试验、对比分析等步骤完成参数的联合优选,并用台湾浅滩实测数据进行了验证。结果表明,优化后的参数可有效提升多波束数据自动处理的精度和效率。本文成果可应用于国产多波束测深处理软件的深化研发以及多波束实测数据处理。 展开更多
关键词 多波束测深 CUBE算法 参数优选 算法原理 数学模型
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海底底质分类反向散射强度三维概率密度法 被引量:7
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作者 金绍华 李家彪 +2 位作者 吴自银 边刚 崔杨 《测绘学报》 EI CSCD 北大核心 2019年第1期124-131,共8页
反向散射强度随入射角变化信息蕴含海底底质特性,是多波束海底底质分类的重要数据源。目前,多波束海底底质分类主要提取平均反向散射强度随入射角的变化信息或基于声呐图像,没有综合考虑两者的相关信息。本文综合考虑平均反向散射强度... 反向散射强度随入射角变化信息蕴含海底底质特性,是多波束海底底质分类的重要数据源。目前,多波束海底底质分类主要提取平均反向散射强度随入射角的变化信息或基于声呐图像,没有综合考虑两者的相关信息。本文综合考虑平均反向散射强度随入射角变化信息及其概率密度分布,绘制三维概率密度图,提出了基于反向散射强度三维概率密度图的海底底质分类方法。实例计算结果表明:该方法能直观表达多波束条带覆盖区内不同海底底质类型的数量,有效判断不同海底底质类型的边界,实现海底底质类型的快速识别。 展开更多
关键词 多波束 反向散射强度 海底入射角 三维概率密度图 海底底质分类
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罗斯海西部末次冰盛期以来沉积环境重建:有机碳与生物标志化合物分析 被引量:2
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作者 宋乐慧 韩喜彬 +3 位作者 李家彪 高抒 刘庚 龙盼盼 《海洋学报》 CAS CSCD 北大核心 2019年第9期52-64,共13页
本文研究采自位于南极罗斯海西部的ANT32-RB16C柱状沉积物,根据粒度、有机碳和生物标志化合物数据探讨末次冰盛期(24.8~20 ka BP)以来该地区有机质来源及沉积环境特征。该柱状样记录了冰架下沉积、冰架前沉积、开阔海域沉积的沉积环境... 本文研究采自位于南极罗斯海西部的ANT32-RB16C柱状沉积物,根据粒度、有机碳和生物标志化合物数据探讨末次冰盛期(24.8~20 ka BP)以来该地区有机质来源及沉积环境特征。该柱状样记录了冰架下沉积、冰架前沉积、开阔海域沉积的沉积环境。指示有机质来源的生物标志化合物指标表明该柱状样中所含有机质主要为浮游植物、细菌等海源输入,同时伴有少量陆源物质混合输入。末次冰盛期,由于冰架的影响有机质含量较低,环流影响使得有机质受低等浮游藻类生物等海源影响较大。末次冰消期(20~11.7 ka BP),罗斯冰架消退,冰川溶解释放的有机质在此沉积,使得陆源有机质输入增多,有机质含量升高。进入全新世,有机质含量较末次冰盛期和末次冰消期明显升高,海源输入比例增大,同时细菌等原核生物增多,导致短链正构烷烃降解程度较大。研究区的氧化还原环境主要受冰架与海冰限制作用的影响,与有机质含量和高氧的南极底层水关系不大。总体来说,从末次冰盛期到末次冰消期,研究区沉积环境受罗斯冰架进退影响,全新世以来受气候变化影响。 展开更多
关键词 有机质 生物标志化合物 沉积环境 末次冰盛期 罗斯海
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The morphotectonics and its evolutionary dynamics of the central Southwest Indian Ridge (49° to 51°E) 被引量:8
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作者 liANG Yuyang li jiabiao +4 位作者 li Shoujun RUAN Aiguo NI Jianyu YU Zhiteng ZHU Lei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期87-95,共9页
The morphotectonic features and their evolution of the central Southwest Indian Ridge (SWIR) are dis- cussed on the base of the high-resolution flfll-coverage bathyraetric data on the ridge between 49°-51°... The morphotectonic features and their evolution of the central Southwest Indian Ridge (SWIR) are dis- cussed on the base of the high-resolution flfll-coverage bathyraetric data on the ridge between 49°-51°E. A comparative analysis of the topographic features of the axial and flank area indicates that the axial topogra- phy is alternated by the ridge and trough with en echelon pattern and evolved under a spatial-temporal mi- gration especially in 49°-50.17°E. It is probably due to the undulation at the top of the mantle asthenosphere, which is propagating with the mantle flow. From 50.17° to 50.7°E, is a topographical high terrain with a crust much thicker than the global average of the oceanic crust thickness. Its origin should be independent of the spreading mechanism of ultra-slow spreading ridges. The large numbers of volcanoes in this area indicate robust magmatic activity and may be related to the Crozet hot spot according to RMBA (residual mantle Bouguer anomaly). The different geomorphological feature between the north and south flanks of the ridge indicates an asymmetric spreading, and leading to the development of the OCC (oceanic core complex). The tectonic activity of the south frank is stronger than the north and is favorable to develop the OCC. The first found active hydrothermal vent in the SWIR at 37°47'S, 49°39'E is thought to be associated with the detach- ment fault related to the OCC. 展开更多
关键词 ultra-slow spreading multibeam bathymetry MORPHOTECTONICS oceanic core complex Southwest Indian Ridge
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The geomorphological features and continuity of the Kyushu-Palau Ridge (KPR) 被引量:7
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作者 TANG Yong li Mingbi +1 位作者 li jiabiao WU Zhaocai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第5期114-124,共11页
The Philippine Basin,surrounded by a series of oceanic trenches,is an independent deep ocean basin in the West Pacific Ocean.Its middle part is divided into three marginal sea sub-basins by the Kyushu-Palau and West M... The Philippine Basin,surrounded by a series of oceanic trenches,is an independent deep ocean basin in the West Pacific Ocean.Its middle part is divided into three marginal sea sub-basins by the Kyushu-Palau and West Mariana Ridges,namely,the West Philippine Basin,the Shikoku and Parece Vela Basins and the Mariana Trough.This paper,through the analysis of the geomorphologic features and gravity and magnetic characteristics of the basin and identification of striped magnetic anomalies,suggests that the entire Philippine Basin developed magnetic lineation of oceanic nature,and therefore,the entire basin is of the nature of oceanic crust.The basin has developed a series of special geomorphic units with different shapes.The KPR runs through the entire Philippine Basin.From the view of geomorphologic features,the KPR is a discontinuous seamount chain (chain-shaped seamounts) and subduction beneath the Japanese Island arc at the Nankai Trough which is the natural boundary between the basin and the Japanese Island arc.At the positions of 25 N,24 N,23 N and 18 N,obvious discontinuity is shown,which belongs to natural topographic discontinuity.Therefore,the KPR is topographically discontinuous. 展开更多
关键词 Kyushu-Palau Ridge (KPR) Philippine Basin Seamount chain (chain-shaped seamounts)
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Rifting characteristics of eastern subbasin of South China Sea and its spreading pattern 被引量:3
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作者 li jiabiao Jin Xianglong Gao Jinyao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第1期77-85,共9页
With processing and interpretation of 25 000 km full-coverage multibeam swath data fromthe eastern South China Sea, it is found that NE-trending and NW-trending linear morphological features such as scarps, horsts and... With processing and interpretation of 25 000 km full-coverage multibeam swath data fromthe eastern South China Sea, it is found that NE-trending and NW-trending linear morphological features such as scarps, horsts and grabens, govern the central part (14°-17° N) of eastern subbasin. Compared with reflection seismic profiles, these NE-trending linear morpho-structures are considered to be the representation of basement structures on seabed and can be divided into three linear structural zones. The trend of the central zone is NE45°-50° occurring around extinct spreading center, the trend of the second zone is NE70° - 78° on both sides of the central one and the trend of the third zone is about NE60° just on the north of the second one. These three NE-trending linear zones are formed in late-stage NW - SE-trending seafloor spreading of the eastern subbasin along NW-trending linear faults, and respectively correspond to three spreading episodes: 17.0- 19.0 Ma (5d-5e), 19.0 - 21.0 Ma (5e-6a) and 21.0 - 24.2 Ma (6a-6c) based on the contrast of morpho-structures to magnetic lineation anomalies. 展开更多
关键词 Multibeam echosounding swath topography morpho-structures spreading pattern
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Distribution of large-scale detachment faults on mid-ocean ridges in relation to spreading rates 被引量:2
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作者 YU Zhiteng li jiabiao +3 位作者 liANG Yuyang HAN Xiqiu ZHANG Jie ZHU Lei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期109-117,共9页
Large-scale detachment faults on mid-ocean ridges (MORs) provide a window into the deeper earth. They have megamullion on their corrugated surfaces, with exposed lower crustal and upper mantle rocks, rela- tively hi... Large-scale detachment faults on mid-ocean ridges (MORs) provide a window into the deeper earth. They have megamullion on their corrugated surfaces, with exposed lower crustal and upper mantle rocks, rela- tively high residual Bouguer gravity anomaly and P-wave velocity, and are commonly associated with ocean- ic core complex. According to 30 detachment faults identified on MORs, we found that their distances to the axis mostly range from 5 to 50 km, half-spreading rates range from 6.8 to 17 mm/a, and activity time ranges from recent to 3 Ma. Most of the detachment faults are developed on the slow spreading Mid-Atlantic Ridge (MAR) and ultra-slow spreading Southwest Indian Ridge (SWIRl, with the dominant half-spreading rates of 7-13 mm/a, especially 10-13 mm/a. Furthermore, they mostly occur at the inside corner of one segment end and result in an asymmetric seafloor spreading. The detachment faults on MORs are mainly controlled by the tectonism and influenced by the magmatism. Long-lived detachment faults tend to be formed where the ridge magma supply is at a moderate level, although the tectonism is a first-order controlling factor. At the slow spreading ridges, detachment faults tend to occur where local magma supply is relatively low, whilst at the ultra-slow spreading ridges, they normally occur where local magma supply is relatively high. These faults are accompanied by hydrothermal activities, with their relationships being useful in the study of hydrothermal polymetallic sulfides and their origin. 展开更多
关键词 detachment faults oceanic core complex spreading rates DISTRIBUTION TECTONISM magmasupply hydrothermal vents
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Robust LS-SVM regression for ore grade estimation in a seafloor hydrothermal sulphide deposit 被引量:2
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作者 ZHANG Xunan SONG Shiji +1 位作者 li jiabiao WU Cheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第8期16-25,共10页
Due to the geological complexities of ore body formation and limited borehole sampling, this paper propos- es a robust weighted least square support vector machine (LS-SVM) regression model to solve the ore grade es... Due to the geological complexities of ore body formation and limited borehole sampling, this paper propos- es a robust weighted least square support vector machine (LS-SVM) regression model to solve the ore grade estimation for a seafloor hydrothermal sulphide deposit in Solwara 1, which consists of a large proportion of incomplete samples without ore types and grade values. The standard LS-SVM classification model is applied to identify the ore type for each incomplete sample. Then, a weighted K-nearest neighbor (WKNN) algorithm is proposed to interpolate the missing values. Prior to modeling, the particle swarm optimiza- tion (PSO) algorithm is used to obtain an appropriate splitting for the training and test data sets so as to eliminate the large discrepancies caused by random division. Coupled simulated annealing (CSA) and grid search using 10-fold cross validation techniques are adopted to determine the optimal tuning parameter- s in the LS-SVM models. The effectiveness of the proposed model by comparing with other well-known techniques such as inverse distance weight (IDW), ordinary kriging (OK), and back propagation (BP) neural network is demonstrated. The experimental results show that the robust weighted LS-SVM outperforms the other methods, and has strong predictive and generalization ability. 展开更多
关键词 weighted LS-SVIVl.grade estimation incomplete samples data division
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Inversion of teleseismic waves at Shidao Seismographic Station 被引量:1
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作者 RUAN Aiguo li jiabiao +2 位作者 HAO Tianyao WU Qingju XU Yi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第5期63-73,共11页
Teleseismic datasets at the Shidao Seismographic Station, located in the northwestern South China Sea, are used to determine the earth anisotropy and the vertical distribution pattern of the shear wave velocity by inv... Teleseismic datasets at the Shidao Seismographic Station, located in the northwestern South China Sea, are used to determine the earth anisotropy and the vertical distribution pattern of the shear wave velocity by inversion approaches. The rotated correction function is applied to analyzing high quality SeS records from five earthquakes at distance of 25°-35° to obtain shear wave splitting parameters of the lithosphere. The result from the deepest earthquake among the five events indicates that the polarization of the fast shear wave is N94°E, which means the direction of extensional stress or the moving of the upper mantle mass in Xisha Islands is nearly west to east and confirms that the crust in this region is a transitional one and the driving force beneath the crust is from the moving mass consistent with the Eurasian plate. The anisotropy effective thickness is estimated about 100 km based on the time delay of 1.3 s between the fast and slow shear waves. The receiver function is applied to analyzing high quality P wave records from nine earthquakes at distance of 20°- 60° to obtain the vertical distribution pattern of shear wave velocity beneath the station. The result indicates that the crust could be divided into three layers: the uppermost crust (5 km above) is a velocity gradient zone consisting of several small layers, where the shear wave velocity increases from 1.5 to 3.5 km/s gradually; the 5 - 16 km depth interval also consiss of several small layers of which the mean velocity is about 3.8 km/s; and the lower crust ( 16.0 - 26. 5 km) is an obvious low velocity layer with a velocity of about 3.6 km/s. The buried depth of the Moho discontinuity is 26.5 kin, the mean velocity of the layers beneath the Moho is about 4.7 km/s and there is an obvious low velocity layer just beneath the Moho. Moreover, analysis of the arrival time of converted waves and the swinging variation of velocity around the initial model suggests that smaller layers in the model maybe are not reliable but the low velocity layer between 16 and 26.5 km maybe is the real one that implies the plasticity of the lower crust. 展开更多
关键词 South China Sea S wave splitting receiver function S wave velocity structure waveform inversion
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北冰洋200海里外大陆架划界主张之比较分析 被引量:1
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作者 尹洁 李家彪 方银霞 《极地研究》 CAS CSCD 北大核心 2020年第4期533-543,共11页
截至2020年,环北冰洋5国中除了尚未批准《联合国海洋法公约》的美国外,其余4国均提交了涉及北冰洋的200海里外大陆架划界案。其中俄罗斯、加拿大和丹麦基于北冰洋海底脊状隆起主张了大范围的大陆架,若全部主张获得大陆架界限委员会认可... 截至2020年,环北冰洋5国中除了尚未批准《联合国海洋法公约》的美国外,其余4国均提交了涉及北冰洋的200海里外大陆架划界案。其中俄罗斯、加拿大和丹麦基于北冰洋海底脊状隆起主张了大范围的大陆架,若全部主张获得大陆架界限委员会认可,那么北冰洋国际海底区域将所剩无几。而北冰洋地质构造的特殊性,在适用《联合国海洋法公约》第76条时存在诸多不确定因素,从而导致外部界限存在多种可能。通过《联合国海洋法公约》第76条、大陆架界限委员会《科学和技术准则》以及审议划界案的实践,比较分析北冰洋沿海国大陆架主张;基于对罗蒙诺索夫脊和阿尔法-门捷列夫脊的科学研究,认为洋脊规则应谨慎适用;北冰洋沿海国将大陆架问题区域化也将产生不利影响。 展开更多
关键词 北冰洋 大陆架划界 自然延伸 洋脊 海底高地
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大陆坡脚确定原则与方法 被引量:1
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作者 方银霞 李家彪 +2 位作者 尹洁 刘为勇 唐勇 《海洋学研究》 CSCD 北大核心 2022年第2期1-9,共9页
大陆坡脚是大陆边缘的一个重要地形特征,是沿海国扩展其大陆架权利和划定其200海里以外大陆架外部界限的基础,也是大陆架界限委员会审议沿海国划界案时特别关注的重要技术参数。《联合国海洋法公约》第76条大陆架制度的制定源于典型的... 大陆坡脚是大陆边缘的一个重要地形特征,是沿海国扩展其大陆架权利和划定其200海里以外大陆架外部界限的基础,也是大陆架界限委员会审议沿海国划界案时特别关注的重要技术参数。《联合国海洋法公约》第76条大陆架制度的制定源于典型的被动大陆边缘。但由于全球大陆边缘的多样性和复杂性,特别是后期构造活动、沉积作用对大陆边缘的改造与影响,海底地形地貌异常复杂多变,导致大陆坡脚的识别非常困难。加上各沿海国为获得最大范围的外大陆架,对大陆坡脚的相关规定进行有利于自己的解释,使得大陆坡脚的确定成了外大陆架划界中一个颇具争议的热点问题。本文基于对《联合国海洋法公约》和《大陆架界限委员会科学和技术准则》对大陆坡脚的规定,结合不同类型大陆边缘的地质特征和各沿海国划界实践,对陆坡基部区的确定、坡度变化最大之点的选取以及相反证明规则的适用性等问题进行了探讨。 展开更多
关键词 大陆坡脚 陆坡基部区 相反证明 洋陆过渡带 外大陆架 划界案
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The architecture of the lower parts of submarine canyons on the western Nigerian continental margin
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作者 JIMOH Rasheed Olayinka TANG Yong +4 位作者 li jiabiao AWOSIKA Larry Folajimi li He AKINNIGBAGE Edward Akintoye ADELEYE Adedayo Oluwaseun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第7期28-40,共13页
Multi-beam,sub-bottom and multichannel seismic data acquired from the western Nigerian continental margin are analysed and interpreted to examine the architectural characteristics of the lower parts of the submarine c... Multi-beam,sub-bottom and multichannel seismic data acquired from the western Nigerian continental margin are analysed and interpreted to examine the architectural characteristics of the lower parts of the submarine canyons on the margin.The presence of four canyons: Avon,Mahin,Benin,and Escravos,are confirmed from the multi-beam data map and identified as cutting across the shelf and slope areas,with morphological features ranging from axial channels,moderate to high sinuosity indices,scarps,terraces and nickpoints which are interpreted as resulting from erosional and depositional activities within and around the canyons.The Avon Canyon,in particular,is characterised by various branches and sub-branches with complex morphologies.The canyons are mostly U-shaped in these lower parts with occasional V-shapes down their courses.Their typical orientation is NE–SW.Sedimentary processes are proposed as being a major controlling factor in these canyons.Sediments appear to have been discharged directly into the canyons by rivers during the late Quaternary low sea level which allows river mouths to extend as far as the shelf edge.The current sediment supply is still primarily sourced from these rivers in the case of the Benin and Escravos Canyons,but indirectly in the case of the Avon and Mahin Canyons where the rivers discharge sediments into the lagoons and the lagoons bring the sediments on to the continental shelf before they are dispersed into the canyon heads.Ancient canyons that have long been buried underneath the Avon Canyon are identified in the multichannel seismic profile across the head of the Avon Canyon,while a number of normal faults around the walls of the Avon and Mahin Canyons are observed in the selected sub-bottom profiles.The occurrence of these faults,especially in the irregular portions of the canyon walls,suggests that they also have some effect on the canyon architecture.The formation of the canyons is attributed to the exposure of the upper marginal area to incisions from erosion during the sea level lowstand of the glacial period.The incisions are widened and lengthened by contouric currents,turbidity currents and slope failures resulting in the canyons. 展开更多
关键词 western Nigerian continental margin submarine canyons ARCHITECTURE controlling factors sedimentary processes tectonic evolution
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Precollisional tectonics and terrain amalgamation offshore southern Taiwan:Characterizations from reflection seismic and potential field data 被引量:8
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作者 li ChunFeng ZHOU ZuYi +3 位作者 li jiabiao CHEN HuanJiang GENG JianHua li Hui 《Science China Earth Sciences》 SCIE EI CAS 2007年第6期897-908,共12页
Sponsored by the Chinese National Fundamental Research and Development Program in 2001,Guang-zhou Marine Geological Survey launched out a long geophysical survey from the northeastern part of the South China Sea (SCS)... Sponsored by the Chinese National Fundamental Research and Development Program in 2001,Guang-zhou Marine Geological Survey launched out a long geophysical survey from the northeastern part of the South China Sea (SCS),through the Luzon Arc,to the Huatung Basin and the Gagua Ridge. Based on high-resolution seismic data from this survey,combined with gravimetric and magnetic modeling,a systematic effort is made to the study of the regional geodynamics offshore southern Taiwan. By focusing particularly on precollisional tectonic interactions between adjacent geological units and their tectonic affiliations,this study can help reveal early arc-continent collisional processes that formed the Taiwan orogen. The construction of the Manila accretionary prism and its eastward progressive deformation indicate that the subduction of SCS have experienced multiple phases of increased activity. Active precollisional crustal shortening within the Northern Luzon Trough resulted in tilting of sedimentary layers at angles between 6° and 13°. But the shortening induced by tilting accounts for only a tiny part of regional total crustal compression. The eastern flank of the Luzon Arc appears to be more active than the rest,evidenced by active faulting and folding in the intra-arc basins on the eastern flank. Magnetic modeling/inversion shows that the Luzon Arc may have experienced multiple phases of magmatic activities,causing lateral magnetic inhomogeneity. Bouguer gravity anomalies and gravity modeling indicate that the Huatung Basin has anomalously higher crustal and upper mantle densities than those of SCS and the Luzon Arc. In addition,there is a large bathymetric difference between the Huatung Basin and the northeastern part of SCS basin. These observations argue against early hypothesis that the Huatung Basin and the northeastern part of SCS basin may once have belonged to one single oceanic crust,in part or in whole. The Gagua Ridge,as a sliver of uplifted oceanic crust,may be related to a transient northwestward subduction of the western Philippine plate. All evidences point to the argument that the region offshore southern Taiwan is experiencing multiple terrain amalgamation,which is a classical model for continental growth. 展开更多
关键词 precollisional TECTONICS TAIWAN OROGEN LUZON Arc GRAVITY and magnetic modeling Bouguer GRAVITY anomaly Huatung Basin
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Passive seismic experiment and ScS wave splitting in the southwestern subbasin of South China Sea 被引量:10
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作者 RUAN AiGuo li jiabiao +2 位作者 LEE ChaoShing QIU Xuelin PAN ShaoJun 《Chinese Science Bulletin》 SCIE CAS 2012年第25期3381-3390,共10页
The seismic experiment of 3D array of OBS in the southwestern sub-basin of the South China Sea(SCS) is briefly introduced in this paper.The data analysis of broadband OBS shows that totally 93 earthquakes with magnitu... The seismic experiment of 3D array of OBS in the southwestern sub-basin of the South China Sea(SCS) is briefly introduced in this paper.The data analysis of broadband OBS shows that totally 93 earthquakes with magnitude of Ms 6.0-6.9 and 10 earthquakes with magnitude above Ms 7.0 were recorded in high quality during this experiment,especially the catastrophic earthquake Ms 9.0 occurred in the east sea area of Japan on March 11,2011.The anisotropy parameters inversion of ScS wave of four events above Ms 7.0 indicates that the fast direction of shear wave is N58°E parallel to the ceased spreading ridge of the southwestern sub-basin of SCS(the slow direction is S35°E perpendicular to the spreading ridge),which means the spreading ridge is under compressing stress at present and the cessation of seafloor spreading is related to such stress field as well. 展开更多
关键词 地震实验 中国南海 西南海盆 分裂 三维数组 数据分析 参数反演 各向异性
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