磁异常相关的四种物理信号性质分析          下载免费PDF全文

卞光浪  翟国君  欧阳永忠  陆秀平  吴太旗  任来平 《海洋测绘》2010,(Z1):13-17

建立了一种特殊坐标系,从理论上推导了磁异常强度、全梯度模信号、张量梯度模信号和拉普拉斯信号等物理信号的表达式,并分析了它们具有的物理性质。 采用仿真计算表明:拉普拉斯信号在空间的等值面非常接近于球面,其在平面上的等值线极大值对应磁性目标中心位置,而其他三种信号在平面上等值线极大值与磁性目标中心位置则存在一定的偏差。 而且四种物理信号随测点至磁性目标中心间距离的衰减速度也存在差异,其中, 拉普拉斯信号与距离呈 5 次方衰减,磁异常强度与距离呈 3 次方衰减,而全梯度模信号和张量梯度模信号与距离都成 4 次方误差。  相似文献   

动态周跳处理方法研究          下载免费PDF全文

范龙  翟国君  柴洪洲  欧阳永忠 《海洋测绘》2010,(Z1):63-68

通过对基于滤波进行周跳处理的 DIA(detection、identification and adaptation)方法、两步 Kalman 滤波法以及连续周跳检验法的分析,提出了接收机高动态情况下也适用的,改进的动态周跳处理方法。 通过选取“当前冶统计模型作为滤波的状态模型,联合利用载波相位和多普勒观测值进行周跳辨识,同时对周跳偏差进行即时估计和改正。 利用机载测量数据模拟不同周跳发生的情况进行计算分析表明,即使在载体运动情况变化较大的情况下, 本文所提出的算法也能够较好的抵御机动误差的影响,对于多周跳和连续周跳的问题都能够快速准确的处理。  相似文献   

A culture-dependent survey of thermophilic bacteria from hot springs in Xiamen area in China     

YANG Bo  OUYANG Jianping  AO Jingqun  CHEN Xinhua 《海洋学报(英文版)》2009,28(1):62-71

Microbes are believed to play important roles in ecosystem function in many environments. The hot springs of Xiamen Island are close to the Xiamen Sea, and may have some characteristics different from those of inland hot springs. Microbes living in the hot springs of Xiamen may have new characteristics. However, little is known about microbial communities of hot springs close to the Xiamen Sea. A culturedependent survey of microbial population in the Xiamen hot springs was performed by using an approach combining total cellular protein profile identification and 16S rRNA gene sequencing. A total of 328 isolates of bacteria were obtained from liquid and sediment samples from the Xiamen hot springs, including neutrophilic thermophilic bacteria and moderately thermophilic acidophiles. Neutrophilic thermophilic bacteria, which grow at a temperature range of 55—90℃ including Rhodothermus marinus (Strain 1), Thermus thermophilus (Strain 2), Thermus thiopara (Strain 3), Geobacillus stearothermophilus (Strain 4), Geobacillus thermoleovorans (Strain 5), and Pseudomonas pseudoalcaligenes (Strain 6), were recovered by 2216E plates. Moderately thermophilic acidophiles, which can grow at temperatures above 50℃ and a pH range of 1.8—3.5 such as Alicyclobacillus acidoterrestris (Strain 8), Sulfobacillus acidophilus (Strain 9), and Sulfobacillus thermosulfidooxidans (Strain 10), were isolated on selective solid medium containing sulfur and Fe2+. Among these strains, Rhodothermus marinus, Thermus thermophilus and Geobacillus stearothermophilus are not only thermophiles, but also halophiles. One bacterium strain (Strain 6) shared 99% nucleotide sequence homology with Pseudomonas pseudoalcaligenes on the 16S rRNA gene sequence, but was quite different from Pseudomonas pseudoalcaligenes in biological characteristics, suggesting that it may represent a novel thermophilic species. Results indicated that various species of neutrophilic thermophiles and moderately thermophilic acidophiles were widely distributed in the Xiamen hot springs and that Rhodothermus marinus and Thermus thermophilus dominated the cultivable microbial community.  相似文献   

基于RS与GIS的北京市热岛研究   总被引：12，自引：0，他引：12  

张兆明  何国金  肖荣波  王威  欧阳志云 《地球科学与环境学报》2007,29(1):107-110

基于普适性单通道算法,利用2005年5月6日的TM数据反演北京市区的实际地表温度。在此基础上,分析了北京市区的热环境特征、热岛分布的位置。运用GIS空间分析工具,分析了地表温度与地形特征和地表覆盖类型之间的关系。结果表明,北京市热岛分布具有环状和带状分布特征,高程较低处和坡度较小处更容易形成热岛中心,不同地表覆盖类型的热特征具有显著的差异。  相似文献   

创伤弧菌和哈氏弧菌双重PCR检测方法的建立及初步应用     

陈福艳  程光平  欧阳贤华  陈晓汉  梁万文  韦友传  黄婷  杨学明  陈明  王瑞  李丽萍  韦明利 《广东海洋大学学报》2013,(3)

根据创伤弧菌(Vibrio vulnificus)的溶细胞毒素基因序列和哈氏弧菌(Vibrio harveyi)的toxR基因序列,分别设计并合成两对特异性引物,通过PCR反应条件优化,测试两种菌的特异性和敏感性,建立双重PCR方法,同时快速检测V.vulnificus和V.harveyi。结果表明:纯培养V.vulnificus和V.harveyi的检测灵敏度分别是12 cfu/mL和18 cfu/mL,与无乳链球菌、海豚链球菌、副溶血弧菌及美人发光杆菌无交叉反应;此PCR检测方法具有良好的特异性、敏感性,具快速、高效等优点,对细菌V.vulnificus和V.harveyi诊断与防治具有较好的临床应用性。  相似文献   

我国硅灰石矿产资源及勘查开发现状和发展建议          下载免费PDF全文

欧阳友和 《山东国土资源》2020,36(12)

我国硅灰石矿资源储量居世界第一,且产量居世界前列。随着多年的勘查与开发,硅灰石矿的开发利用已由传统领域向新的应用领域探索拓展。本文在收集整理现有硅灰石矿床、海关进出口等数据资料的基础上,在全国范围内搜集了77个矿产地,其中超大型8处,划分了7个重要成矿区,总结了我国硅灰石矿产开发利用现状、进出口贸易情况,对硅灰石矿产的行业发展提出了建议。  相似文献   

经典平差模型的扩展   总被引：4，自引：3，他引：1  

欧阳文森  朱建军 《测绘学报》2009,38(1)

将经典测量平差的概括模型(附有等式限制条件的条件平差模型)扩展为附不等式约束的平差模型,同时将其定义为测量平差统一模型,并在一定的条件下实现这种平差模型与概括平差模型间的相互转换.在最小二乘平差原则下,作者结合虚拟观测方程处理不等式约束的思路,给出附不等式约束平差的最小二乘显式解,分析其统计性质,并修正传统测量平差结果的统一表达式.按本文所提方法,附不等式约束的平差问题,完全可以利用传统的平差方法和平差程序求解,方法简单可行.  相似文献   

基于GIS的城市工程建设多测合一管理平台设计与实现     

肖亮  欧阳松南  叶锐铿 《北京测绘》2021,35(6):717-721

近年来,为了加快疏解企业办事堵点、痛点,深化"放管服"改革,优化营商环境建设,最大限度惠企便民,国内许多城市开始深化工程建设项目审批制度改革,全面开展工程建设项目多测合并、联合测绘和成果共享工作.结合东莞市工程建设项目审批的实际情况,探讨多部门协同的多测合一(联合测绘)管理流程,构建多测合一全过程管理数据库,开发东莞市...  相似文献   

基于分数阶时间导数的黏弹性衰减VTI介质中平面波传播     

程时俊  毛伟建  欧阳威 《地球物理学报》2021,64(3):965-981

目前在地震勘探频带范围内通常假设品质因子Q与频率无关,且呈衰减各向同性.事实上,相比较速度各向异性,介质的衰减各向异性同样不可忽视.本文将衰减各向异性和速度各向异性二者与常Q模型相结合,建立了黏弹性衰减VTI介质模型,并基于分数阶时间导数理论,给出了对应的本构关系和波动方程.利用均匀平面波分析和Poynting定理,推...  相似文献   

Carbon isotope evidence of last glacial climate variations in the tropical NW Leizhou Peninsula,South China     

WEI ZHONG  JIAYUAN CAO  JIBIN XUE  JUN OUYANG  HAIMEI WANG  XIAOHONG TANG  XIAOYAN GAO 《Boreas: An International Journal of Quaternary Research》2012,41(1):102-112

Zhong, W., Cao, J., Xue, J., Ouyang, J., Wang, H., Tang, X. & Gao, X. 2012 (January): Carbon isotope evidence of last glacial climate variations in the tropical NW Leizhou Peninsula, South China. Boreas, Vol. 41, pp. 102–112. 10.1111/j.1502‐3885.2011.00224.x. ISSN 0300‐9483. Bulk organic δ¹³C values of sediment sequences are commonly used to indicate past climatic changes, although the causes and mechanisms leading to the observed organic carbon isotope responses are presently not fully understood. Based on two sedimentary sequences, namely a peat profile and a fluvial and swamp sequence from the tropical NW Leizhou Peninsula in South China, we interpret more negative bulk organic δ¹³C values to suggest wetter and warmer conditions, implying a stronger East Asian (EA) summer monsoon, and less negative δ¹³C values to indicate drier and cooler conditions, reflecting a weakening of the EA summer monsoon. A warm and wet period occurred between c. 48.0 and 28.0 cal. ka BP. In the study region, a climate shift occurred at c. 22.0 (or 20.0) cal. ka BP, and the driest and coldest period occurred between c. 19.0 and 16.0 cal. ka BP. After c. 12.0 cal. ka BP, the climate changed towards wetter and warmer conditions. Several possible millennial‐scale dry and cold oscillations characterized possibly by C4 plants, or by more positive organic δ¹³C values during the period when C3 plants dominated, are cautiously and tentatively interpreted as showing a similarity with Heinrich events and other cold millennial‐scale oscillations evidenced from a Greenland ice core and Chinese stalagmite. We demonstrate that bulk organic δ¹³C records of sedimentary sequences in the study region have potential for indicating the changes in vegetation composition that were closely associated with climate variation during the last glacial period.  相似文献