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利用双差层析成像方法反演若尔盖地区三维速度结构,得到该地区的精细三维速度结构和高精度震源位置参数。反演结果显示,研究区速度结构整体呈低速状态,反映出青藏高原内部具有部分熔融物质特性;在青藏高原东北缘地区,强烈的构造变形特征以及低速区蔓延方向印证了青藏高原内部物质向东南方向流溢的科学推测;低速青藏高原板块与相对较硬的若尔盖地块相互挤压导致应力累积,因而在两者的高低速过渡带区域内发生了若尔盖系列地震。 相似文献
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三江地区盐源-丽江及川滇地块的地震活动与构造运动态势 总被引：10，自引：3，他引：7
阐述了盐源－丽江地块的存在及其边界，根据遥感影像等资料论述了该地块范围内强烈地震活动和构造运动，并提出盐丽、川滇等地块的构造及运动态势应是在印度模块北移、压入欧亚板块并与之夹挤的作用下，使其间部分地球物质向东、东南或转向西南移（流）动的表现。 相似文献
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本文用平均风速和最大风速法对若尔盖等三地的韦伯分布参数k、c进行估算,并用韦伯分布计算风能的指标。计算表明:若尔盖、红原属风能可利用区,用风力发电是有利用价值的;阿坝属风能贫乏地区。 相似文献
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利用若尔盖1971-2000年的大风、雷暴、冰雹、积雪、雾及飑的逐年各月气象资料,用现代统计方法,分别逐类、逐月、逐年代统计若尔盖地区旅游气象灾害出现频次、时间变化特征,并对其变化特征及主要旅游气象灾害发生规律进行气候综合分析,结合旅游安全社会经验,统计出若尔盖气象灾害发生月份集中在4-8月,主要是春、夏两个季节。而较少月份集中在8-2月,为秋、冬两季。若尔盖地区适宜旅游期月份为5、6、7、8、9月,非常适宜旅游区月份为6、7、8月,疗养期月份为7月。而该时段为灾害频发期,因此应特别注意对灾害天气的预防和应对。为当地旅游管理部门提供参考,为旅游投资与实施建设提供气象依据,为旅游者选择旅游季节及评估旅游安全提供帮助。 相似文献
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伊宁地块是西天山造山带的重要组成部分,其上广泛出露晚古生代火山岩浆岩和沉积建造,对剖析该地块的形成演化具有重要意义。伊宁地块以中部近EW向展布的乌孙山—塔勒得断裂为界可划分为南、北两大构造带,两者在基底建造、岩浆岩的组成与时代及其地球化学特征、盆地形成和构造演化等方面均呈现显著不同。其中,南构造带由晚泥盆世—早石炭世早期大哈拉—喀勒峻岛弧带和阿腾套弧后伸展盆地构成,推测海沟位于岛弧带之南(那拉提南缘断裂附近);北构造带由早石炭世中晚期阿吾拉勒叠加岛弧带、特克斯—新源弧前盆地和清水河—苏布台弧后盆地-扇三角洲构成。在重新梳理并详细总结伊宁地块的最新划分依据及方案基础上,首次提出伊宁地块形成与演化的南、北构造带两拼接和演化三阶段新认识:①晚泥盆世—早石炭世早期,南构造带初始弧-盆构造体系形成;②早石炭世中晚期,北构造带的沟-弧-盆构造体系形成并增生;③早—晚石炭世,初始的南构造带与增生的北构造带拼贴缝合,完成地块拼贴与增生,最终形成统一的伊宁地块。 相似文献
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实现复杂场景下地块级苹果园的精准制图,是中国苹果产业精细化管理面临的迫切需求。然而,传统的地块级分类制图框架在处理小农经营区内的大量细碎地块时,可靠性大幅度降低。本文提出一种适用于复杂场景下小农经营区的地块级苹果园模块化制图方法框架。(1)基于模拟人类对目标场景视觉感知的分层策略,从深秋季的单幅超高空间分辨率（Very High Resolution, VHR）影像中提取冗余的候选地块;(2)利用非对称瓶颈网络（Depth-wise Asymmetric Bottleneck Network, DABNet）模型与长短期记忆（Long Short-Term Memory, LSTM）模型,分别从VHR影像与时间序列影像中提取苹果园的空间特征像素与时序特征像素。然后,构建元特征描述特征像素在候选地块中的分布情况,与地块的内在特征共同组成苹果园地块的分类特征;(3)使用随机森林（Random Forest, RF）将候选地块分类为苹果园地块和非苹果园地块。以山东省栖霞市西城镇为研究区,从43238个候选地块中提取出30 292个苹果园地块,分类总体精度达到92.7%。利用RF算法自带的平均... 相似文献
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耕地地块作为精准农业的重要支撑,现有地块边界大多依靠人工勾绘。随着遥感技术的发展,基于遥感影像自动提取耕地地块成为研究主要方向,其中基于深度学习的方法能够克服传统检测方法难以适应复杂场景的局限而被广泛使用,但现有检测方法仍存在问题,基于深度卷积模型直接识别耕地区域会丢失内部边界、而基于边缘检测模型识别耕地边界时则会同时得到大量无关边界;此外,现有的基于阈值提取地块的策略所提取的地块不够规整,存在内陷的问题。针对上述问题,本研究提出一种基于深度卷积网络和分水岭分割的耕地地块提取方法,从信息检测和地块提取两方面进行改进：① 将耕地边界视作一种地物类别,在深度卷积网络中进行类别概率检测,帮助实现对耕地边界的语义识别。② 基于改进后的D-LinknetXt网络进行检测,其网络架构适合于对耕地边界这类线性目标的提取,同时更换原始D-Linknet网络的残差单元,帮助提高了网络的特征提取能力。③ 基于分水岭分割对耕地地块进行提取,利用了区域分割方法获取边界的封闭性,并且这种以区域为单元进行分割并合并的方式,解决了原有方法在像元尺度上基于阈值提取所遇到的提取地块存在内陷的问题,使地块更规整准确。在一景高分二号影像上进行检验,并设计两类精度指标,从全局边界精度和地块几何精度两方面进行方法性能评估。实验结果表明,本方法的精度优于3种对比方法,在代表边界精度的F1分数上达到了0.933,地块几何精度为0.829。本研究所提出的方法能够更加准确的对耕地地块进行提取,并适用于实际应用中。 相似文献
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佳木斯地块是西伯利亚板块与华北板块之间一个重要的中间地块，其西缘通过嘉荫—牡丹江缝合带与松嫩地块相连，其东缘通过大和镇缝合带与完达山中生代板片相连。近年来，亚洲大陆东缘的构造及演化已引起许多学者的注意，本文试就佳木斯地块东缘晚古生代陆缘构造性质及其演化提出粗浅认识。 相似文献
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文章提出一种基于地块形状测度的地块变化监测方法,该法在保证较高精度和计算效率的前提下,能快速监测土地利用规划变化前后的整体情况。实验结果表明,该方法具有较好的精度保证,有良好的应用前景。 相似文献
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The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature. 相似文献
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《极地研究(英文版)》2014,(4)
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose 相似文献
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《中国海洋大学学报(英文版)》2014,(4)
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail 相似文献
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《中国海洋大学学报(英文版)》2014,(6)
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo- 相似文献
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Massimo GRECO 《山地科学学报》2014,(6):1383-1384
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a 相似文献
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As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m. 相似文献
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Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area. 相似文献
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Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter. 相似文献
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正Rapid changes of Arctic sea ice cover have been in the focus of the international climate research community in recent years.Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean.Up to now,China has performed six research cruises to the Arctic Ocean resulting in a significant volume of research output.Improved knowledge on the atmospheree-sea ice-ocean interactions in the Arctic is a 相似文献