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131.
对 ODV这一海洋数据视图应用软件包作了介绍。着重介绍了 ODV的主要特点、数据可视化模式、用户界面及其功能概要。  相似文献   
132.
针对街景影像中斑马线的自动检测与定位识别率和定位精度不高的问题,文章引入俯视投影与霍夫直线检测来改进基于双极系数的斑马线识别算法,并设计球面全景单像测量方法对斑马线进行粗略定位:对全景图像上路面区域进行俯视投影,使图像各处比例尺保持一致;对路面俯视图分块计算以生成双极系数图,并用形态学中闭运算与开运算进行处理;对候选区域进行霍夫直线检测,利用直线长度与方向的统计信息来排除干扰;最后使用单像量测方法对斑马线进行自动地理定位。实验结果证明,该方法对街景中的斑马线具有较高的识别率与定位精度。  相似文献   
133.
Tomogashima Strait, which is an entrance of Osaka Bay, is a very important area for material transport because a large volume of pollutant-rich water in Osaka Bay is transported through this strait. We have investigated the cross sectional structures of current and material fluxes at Tomogashima Strait, Osaka Bay. Tidal current and residual flow patterns in cross section at Tomogashima Strait during summer and winter are almost the same, and residual flow in summer is stronger than that in winter. However, the net water exchange through the strait in summer was almost the same volume as that in winter. At Tomogashima Strait, total suspended matter (TSM) and particulate organic carbon (POC), and individual nitrogen and phosphorus compartments in Osaka Bay always flowed out except particulate organic nitrogen (PON). The average outflows of total nitrogen (TN) and total phosphorus (TP) at Tomogashima Strait over a year were calculated to be 145 ton/d and 30 ton/d, respectively. The average outflow of DIN and DIP at Tomogashima Strait over a year were 95 ton/d and 13 ton/d (DIN/DIP = 16), respectively. Residence times of both DIN and DIP in Osaka Bay were estimated to be about two months.  相似文献   
134.
We investigate by first-principles calculations the effect of ferrous iron, Fe2+, on the structure and the equation of state of MgSiO3 post-perovskite. We find that ferrous iron is high-spin over the pressure range of the mantle assuming a ferromagnetic structure. The bulk modulus and the specific volume increase with the addition of ferrous iron to MgSiO3. We find that Fe partitions preferentially to post-perovskite and broadens the two-phase pressure range.  相似文献   
135.
桂林市三维地形立体显示与分析系统   总被引:8,自引:0,他引:8  
“桂林市三维地形立体显示与分析系统”利用了GIS和RS技术开发研制。它以数字化的地形图为核心数据源,建立数字高程模型,以卫星遥感数字图像为三维景观的表层粘模。具有二维平面—三维立体图对照显示、地形数据与专业图像数据迭合显示和任意调整观察(飞行)参数等功能,并可以按预设的路线模拟飞行观察。还具有绘制剖面、分析地形坡度、求算面积和土石方量(或水库库容)、综合背景查询和工程适宜性评价等功能,有较高的实用价值。  相似文献   
136.
重点介绍王鹏飞先生在气象学分科之一的中国气象史志研究方面的卓越贡献,尤其是在理论研究的深化和专业研究的推进两个方面的重要建树。王鹏飞先生是中国气象史志研究的主要开拓者和领导者之一,他的辛勤努力将中国气象史志研究推向了新高度。尽管所回顾的是王鹏飞先生多年前的工作,但对今天日益繁荣的气象史志研究仍然有具体指导作用。2020年是南京信息工程大学60周年校庆,王鹏飞先生作为学校早期主要建校骨干之一,为学校今日的双一流学科做出了显著贡献。今年也是王鹏飞先生诞辰100周年,此文也表达了对王鹏飞先生的诚挚纪念。  相似文献   
137.
以科学发展观为指导.从高等教育的办学规律出发,对信息学院发展的目的、本质、内涵和模式进行了认真的分析和思考。认为要实现信息学院全面、协调、可持续的健康发展。就要实现学科建设、教学科研、管理工作、对外交流、思想政治工作等方面的协调发展;实现规模、质量、结构、效益的有机统一;实现以学生为本、以教师为本,促进人的全面发展。认为要有先进的办学理念,准确的办学定位,合理的发展规划和正确的舆论导向,从而在思想认识和宏观战略层面上全面落实科学发展观;要认真分析教学、科研、管理、改革、思想工作等业务领域的实际情况,并正确处理他们之间的相互关系,寻找学院不同阶段的工作切入点。从而在办学实践和具体工作层面上全面落实科学发展观。  相似文献   
138.
The 2008 Gaize MW6.4 earthquake,occurring on the tensional active fault zone located between Lhasa terrane and Qiangtang terrane in the interior of Tibet is a typical normal-faulting event.In this paper,we resolve the three-dimensional coseismic displacement fields of the earthquakes using a least-square iterative approximation solution with a priori knowledge,according to the theoretical basis that InSAR measurements are extremely insensitive to N-S component.Results show that the boundary dividing the two sides of the main-shock fault is very clear in the vertical movement,and two remarkable subsidence centers can be observed on the hanging wall,while amplitude of the west one (-48.9cm) is larger than the east (-41.4cm),but the maximum uplift on the footwall is only 5cm.In addition to some northward movement with amplitude less than 5cm around the aftershock fault,the north-south deformation field suggests an overall southward movement.The three-dimensional results indicate that the induced surface movement is predominantly vertical and mostly occurred on the upper side,while there are obvious east-west separation and eastward rotation in the horizontal plane.The full vectors are consistent with simulated deformation field with the RMSE less than 6cm,so the research demonstrates the feasibility of the method to recover precise three-dimensional deformation field.On the whole,the three-dimensional deformation field coincides with the tensile fracture characteristics of Gaize earthquakes,and the tectonic stress background of coeval east-west extension and north-south shortening.  相似文献   
139.
Different high‐resolution techniques can be employed to obtain information about the three‐dimensional (3D) surface of glaciers. This is typically carried out using efficient, but also expensive and logistically demanding, light detection and ranging (LiDAR) technologies, such as airborne scanners and terrestrial laser scanners. Recent technological improvements in the field of image analysis and computer vision have prompted the development of a low‐cost photogrammetric approach, which is referred to as ‘structure‐from‐motion’ (SfM). Combined with dense image‐matching algorithms, this method has become competitive for the production of high‐quality 3D models. However, several issues typical of this approach should be considered for application in glacial environments. In particular, the surface morphology, the different substrata, the occurrence of sharp contrast from solar shadows and the variable distance from the camera positions can negatively affect the image texture, and reduce the possibility of obtaining a reliable point cloud from the images. The objective of this study is to test the structure‐from‐motion multi view stereo (SfM‐MVS) approach in a small debris‐covered glacier located in the eastern Italian Alps, using a consumer‐grade reflex camera and the computer vision‐based software PhotoScan. The quality of the 3D models produced by the SfM‐MVS process was assessed via the comparison with digital terrain models obtained from terrestrial laser scanning (TLS) surveys that were performed at the same epochs. The effect of different terrain gradients and different substrata (debris, snow and firn) was also evaluated in terms of the accuracy of the reconstruction by SfM‐MVS versus TLS. Our results show that the quality of this new photogrammetric approach is similar to the quality of TLS and that point cloud densities are comparable or even higher compared with TLS. However, special care should be taken while planning the SfM survey geometry, to optimize the 3D model quality and spatial coverage. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
140.
基于街景图像的城市环境评价研究综述   总被引:1,自引:0,他引:1  
城市环境评价研究传统上采用基于现场调研的方法,难以在大范围、精细化的尺度上进行评估。街景图像具有覆盖面广、能提供街道层级景观信息,且数据采集成本低的优势,为城市环境评价研究提供了大样本数据源和新的研究思路。人工智能技术的不断突破和其在各领域的应用,使得在大范围空间尺度上,基于街景图像进行城市环境评价研究成为可能。本文首先对城市环境评价常用的3种数据源(街景图像、遥感影像和地理标记社交媒体数据)进行对比分析,归纳街景图像在城市环境评价中的优势;然后,从方法学的角度把基于街景图像进行城市环境评价过程中使用的方法分为4大类别(基于图像分析的方法、基于统计分析的方法、基于人工智能的方法和基于空间分析的方法);接着,从城市物理环境、社会环境、经济环境、美学环境,综述了街景图像在城市环境评价中的应用研究进展;最后,对现有研究成果进行了总结并对未来研究方向提出展望。  相似文献   
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