一种改进YOLOv4的遥感影像典型目标检测算法

如何使传统神经网络算法对遥感影像典型目标检测表现出良好的适应性是当前遥感领域的一项难点.在深入解析最新YOLOv4网络结构及算法核心思想前提下,首先通过增加104×104的特征层尺度并嵌入SE模块进行网络结构改进;继而根据待检测目标尺度特点调整锚点框,提高YOLOv4算法对遥感影像典型目标检测性能;最后设计对照实验进行...     

Integrated Reservoir Prediction and Oil-Gas Evaluation in the Maoshan Area

The Maoshan area is an area with well-developed igneous rocks and complex structures. The thickness of the reservoirs is generally small. The study of the reservoirs is based on seismic data, logging data and geological data. Using techniques and software such as Voxelgeo, BCI, RM, DFM and AP, the authors have made a comprehensive analysis of the lateral variation of reservoir parameters in the Upper Shazu bed of the third member of the Palaeogene Funing Formation, and compiled the thickness map of the Shazu bed. Also, with the data from ANN, BCI and the abstracting method for seismic characteristic parameters in combination with the structural factors, the authors have tried the multi-parameter and multi-method prediction of petroleum, delineated the potential oil and gas areas and proposed two well sites. The prediction of oil and gas for Well JB2 turns out to be quite successful.     

微晶萘－双十二烷基二硫代乙酰二胺吸附显色连续测定铂和钯

微晶萘－双十二烷基二硫代乙酰二胺（ＤＤＯ）吸附显色剂与铂（Ⅱ）、钯（Ⅱ）卤络合物所形成的有色螫合物沉淀，经分离洗涤后分别溶于氯仿－石油醚混合溶剂中，于５１０ｎｍ和４４５ｎｍ处测定铂和钯螫合物的吸光度，在１０ｍＬ的ＣＨＣＩ３－石油醚中０～１０μｇＰｔ及Ｐｄ均符合比尔定律。采用在铜镍矿基体中标准加入法检验所拟方法，钯的回收率为９３．３％～１０６．７％，铂为９０％～１０６％。     

四川南江桥亭、流坝剖面裂缝特征研究

川东北及川北是未来几年中国油气勘探开发的重点地区,这个地区的储层类型主要以裂缝-孔隙型为主。通过对南江桥亭、流坝剖面野外地质调查,认为南江地区裂缝可分为成岩缝与构造缝两大类,其中成岩缝有成岩收缩缝和压溶缝合线两种类型;构造缝主要有与岩层面垂直、与水平面垂直、与岩层面低角度相交、与水平面低角度相交的剪切缝及纵张缝、顺层缝和共轭剪切带雁列张裂缝等七种类型。     

张其昀主编的《方志月刊》及其地理学贡献

《方志月刊》是中国近代唯一的一种侧重于区域地理的刊物,刊物的名称选择、编辑特色等均受到了主编张其昀地理学思想的影响。通过对《方志月刊》载文及相关史实的梳理与考证,解析其办刊特色和地理学贡献。研究表明：该期刊注重科学的区域地理研究和地图、照片的运用,注重国外地理学成果的介绍和地理学史的整理,为中国近代地理学特别是区域地理学的发展提供了有益导向。     

CFG桩在某大型油罐局部地基处理中的应用

通过工程实例,介绍CFG桩在大型油罐地基局部处理中,既有效提高软弱地基强度,又最大限度保持不同地基变形协调一致的处理方法.针对油罐体型的特殊性,采用了沿油罐圆心环形布桩,并且根据不同地段地基土性质的纵横向差异采用不等距布桩的方案.复合地基处理效果理想,达到了预期的设计目的,为类似工程的地基处理提供了一种新的设计理念,供类似工程参考.     

Seasonal variation in species composition and abundance of demersal fish and invertebrates in a Seagrass Natural Reserve on the eastern coast of the Shandong Peninsula,China

Seagrass habitats are structurally complex ecosystems, which support high productivity and biodiversity. In temperate systems the density of seagrass may change seasonally, and this may influence the associated fish and invertebrate community. Little is known about the role of seagrass beds as possible nursery areas for fish and invertebrates in China. To study the functioning of a seagrass habitat in northern China, demersal fish and invertebrates were collected monthly using traps, from February 2009 to January 2010. The density, leaf length and biomass of the dominant seagrass Zostera marina and water temperature were also measured. The study was conducted in a Seagrass Natural Reserve(SNR) on the eastern coast of the Shandong Peninsula, China. A total of 22 fish species and five invertebrate species were recorded over the year. The dominant fish species were Synechogobius ommaturus, Sebastes schlegelii, Pholis fangi, Pagrus major and Hexagrammos otakii and these species accounted for 87% of the total number of fish. The dominant invertebrate species were Charybdis japonica and Octopus variabilis and these accounted for 98% of the total abundance of invertebrates. There was high temporal variation in species composition and abundance. The peak number of fish species occurred in August–October 2009, while the number of individual fish and biomass was highest during November 2009. Invertebrate numbers and biomass was highest in March, April, July and September 2009. Temporal changes in species abundance of fishes and invertebrates corresponded with changes in the shoot density and leaf length of the seagrass, Zostera marina.     

苏北废黄河三角洲侵蚀后退过程及其对潮流动力的影响研究

以苏北废黄河三角洲及其毗邻海域的南黄海旋转潮波为研究对象,在恢复黄河北归以来苏北废黄河三角洲海岸不同发育阶段岸线位置和水下地形的基础之上,通过所建立的潮波数学模型,研究了在苏北废黄河三角洲不同演变阶段南黄海潮波运动的特征及其变化。研究表明:在1855年黄河北归前,由于废黄河口岸线向外突出20余千米且有宏大的水下三角洲,由北向南传播的潮波受到阻挡,处在其南侧的辐射沙脊区水动力相对较弱;随着江苏海岸线后退,废黄河口水下三角洲夷平,由北向南传播的潮波变得更加顺畅,南黄海旋转潮波得到不断加强,辐射沙脊北部的西洋水道及中南部的烂沙洋水道、小庙洪水道深槽区水动力随着废黄河三角洲的侵蚀后退,平均流速和最大流速均表现为增大的趋势。