爆炸装置搜索视景仿真训练系统的设计与实现   总被引：1，自引：0，他引：1  

孙建顺  华泽玺  黄皇 《成都信息工程学院学报》2012,27(4):390-395

为解决搜爆人员在爆炸装置搜索训练过程中,真实训练环境搭建繁琐、人力与物资成本投入大等问题,在分析搜索爆炸装置训练过程的基础上,设计了一套爆炸装置搜索训练视景仿真系统。该系统通过搜爆场景逐级细化的方法构建虚拟场景,且以具有感应能力的三维模型模拟摩尔探测仪与非线性节点探测仪等搜爆工具。基于Open Scene Graph(OSG)图形开发库,以VC++为开发环境实现了爆炸装置搜索训练视景仿真。实践证明:该系统仿真度高,达到了爆炸装置搜索仿真训练的效果,并且运行流畅,沉浸感强。  相似文献   

Design and implementation of a 3D ocean virtual reality and visualization engine     

CHEN Ge  LI Bo  TIAN Fenglin  JI Pengbo  LI Wenqing 《中国海洋大学学报(英文版)》2012,11(4):481-487

In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine applications.The design goals of VV-Ocean aim at high fidelity simulation of ocean environment,visualization of massive and multidimensional marine data,and imitation of marine lives.VV-Ocean is composed of five modules,i.e.memory management module,resources management module,scene management module,rendering process management module and interaction management module.There are three core functions in VV-Ocean:reconstructing vivid virtual ocean scenes,visualizing real data dynamically in real time,imitating and simulating marine lives intuitively.Based on VV-Ocean,we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface.Environment factors such as ocean current and wind field have been considered in this simulation.On this platform oil spilling process can be abstracted as movements of abundant oil particles.The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering.VV-Ocean can be widely used in ocean applications such as demonstrating marine operations,facilitating maritime communications,developing ocean games,reducing marine hazards,forecasting the weather over oceans,serving marine tourism,and so on.Finally,further technological improvements of VV-Ocean are discussed.  相似文献   

Suppression of internal multiples based on virtual events     

LIU Yi  LIU Yang  LU Qi 《世界地质(英文版)》2013,16(2):113-120

In practical seismic exploration, internal multiples generated when the wave impedance of medium is strong, and seismic records are recorded. The method of virtual event repress internal multiples is to move scattered points from underground to the surface, similar to the method of the surface-related multiple elimination (SRME). The method of SRME belongs to the prediction-subtraction approaches to eliminate internal multiples, prediction method is based on building a brand new way of seismic wave propagation (virtual reflection and virtual event), so that it has forward and backward wave propagation, and through convolution with significant wave to predict the internal multiples. Due to required data needing field information of full-wave, the authors use Seislet transform interpolating the missing data to ensure the premise of internal multiples prediction. The test data show that the above method has achieved good results.  相似文献   

基于反褶积算法的地震干涉技术被动源成像     

王德利  程浩  朱恒  冯飞 《吉林大学学报(地球科学版)》2012,42(6):1920-1926

地震干涉技术可以将任意2个检波器接收到的数据合成为在若干检波器之间传播的波,就好像其中的一个检波器作为一个虚拟震源来发挥作用。它可以从混沌无序的地震信号中发现有用信息,从地震噪声中提取有用信号以此推断地震波穿过介质的地质构造。基于反褶积算法,对其理论公式进行了较详细的推导,实现被动源地震干涉成像,证明了反褶积算法的可行性;并将其结果与互相关算法的结果进行对比,分析了2种方法在信噪比和分辨率方面的差异。数值计算表明,反褶积算法的纵向分辨率比互相关算法的高。对其进行的加噪试算表明,震源叠加后的反褶积算法呈现出高信噪比的特点。  相似文献   

面向户外增强现实的地理实体目标检测     

乔延军  饶锦蒙  王骏星  杜清运  任福 《地理信息世界》2017,24(5)

本文研究了多种计算机视觉领域中用于图像分类和目标检测的卷积神经网络模型,在一种目标检测模型的基础上进行了修改,并结合了残差神经网络结构,旨在解决户外增强现实中地理实体目标检测的问题。我们根据这一模型开发了一款户外增强现实原型系统,通过将训练好的模型作为目标检测引擎,达到了较好的近实时性和准确性。  相似文献   

中国虚拟水战略区划研究   总被引：5，自引：3，他引：2  

邹君  杨玉蓉  毛德华  田亚平 《地理研究》2010,29(2):253-262

为探究我国不同区域虚拟水研究和实践的发展方向,以国内31个省级行政区为研究单元,运用指标体系评价方法和列联表互斥的矩阵分类方法进行了我国虚拟水战略区划研究。结果表明:①依据水资源禀赋指数可以将全国划分为虚拟水输出地域、虚拟水输入地域和虚拟水平衡地域3个一级区划单元;其中,虚拟水输出地域的发展方向是提高水密集型工农业产品的商品率,虚拟水输入地域则应着手准备缩减水密集型产业,而虚拟水平衡地域则不宜进行大规模的虚拟水战略实践。②依据农产品贸易指数和非农水资源需求压力指数,将全国细分为典型输入(出)区、内部优化区、成长输入(出)区、复合型区、潜在输入(出)区和现实输入(出)区共12个二级区划单元,并指出了各二级区的产业发展方向。  相似文献   

基于虚拟钻孔的工程地质三维剖切的实现   总被引：1，自引：0，他引：1  

梁师俊 《地理与地理信息科学》2010,26(1)

给出工程地质数据库的结构,并利用标准地层层序表和钻孔数据,根据层面TIN模型,建立了工程地质三维模型;在此基础上提出一种实用的工程地质三维剖切的实施方法,该方法通过剖切平面与层面TIN边的交点生成虚拟钻孔,把虚拟钻孔所在的地质剖面作为约束条件,将虚拟钻孔和实测钻孔一起重新构建层面TIN模型,并实现工程地质三维剖切。该方法简易可行,对层状地质结构的三维剖切效果较好,能满足工程地质分析和地质解释等应用的实际需要。  相似文献   

基于数字散斑相关方法的虚拟引伸计及其在岩石裂纹动态观测中的应用     

郭文婧  马少鹏  康永军  马沁巍 《岩土力学》2011,32(10):3196-3200

基于数字散斑相关方法（DSCM）发展了一种虚拟引伸计测量方法。该方法通过DSCM测量的应变场识别和定位裂纹,然后“事后”在裂纹处虚拟地安装引伸计,再通过DSCM测量的位移场计算裂纹的张开量和错动量。给出了虚拟引伸计的原理和实现方法,并用实验验证了虚拟引伸计的可靠性,同时分析并标定出虚拟引伸计在实测中可达到0.1像素的分辨率。将虚拟引伸计应用于含未穿透预制裂纹（三维裂纹）的花岗岩试件的破坏实验中,根据虚拟引伸计测得的裂纹张开、错动情况,对试件破坏过程中不同裂纹的出现顺序以及裂纹类型进行了判断,同时对试件破坏的机制进行了简单分析。  相似文献   

新疆2012年水足迹计算与分析     

董蒙  张军民 《中国沙漠》2016,36(4):1162-1170

运用投入产出分析法计算并分析新疆2012年的水足迹,结果表明：新疆2012年总水足迹为292.52×10⁸m³,人均水足迹为1283.94m³。总水足迹中虚拟水消费量为279.68×10⁸m³,其中72.20%用于居民和政府消费,27.80%用于资本形成。水足迹自给率为80.56%,对内部水足迹依赖度较高;水资源经济效益值为25.66元·5m^-3,水足迹价值兑换比例为3.31,水资源经济效益值较低;水资源压力指数为0.68,60%以上的水资源压力来源于虚拟水流出。实现新疆水资源可持续利用可通过优化产业结构、调整居民虚拟水消费结构以降低水足迹,优化贸易结构以发挥虚拟水贸易对平衡水资源供需矛盾、提高水资源利用效率的调节功能。  相似文献   

Global virtual-land flow and saving through international cereal trade     

Jingqi Zhang  Naizhuo Zhao  Xingjian Liu  Ying Liu 《地理学报(英文版)》2016,26(5):619-639

With intense urbanization and sustained population growth, securing food production with limited land sources has increasingly become a pressing issue. Based on an analysis of international cereal (i.e., barley, buckwheat, maize, oats, rice, rye, sorghum, soybean, and wheat) trade and differences in yields of the cereal between export and import countries over the period of 2007 to 2011, we explore the great potential of land saving through the international cereal trade. By ‘land saving’, we refer to the reduced global total of lands required to produce a necessary amount of cereal when cereal is exported from a country with relatively large yield of the cereal to a country with relatively small yield of the cereal. Our scenario analysis suggests that international cereal trade would help mitigate the shortage of domestic arable land for many island countries (e.g., Japan) and countries in the arid Middle East and North Africa (e.g., Syria and Morocco). Furthermore, international cereal trade has the potential to generate ‘land saving’ of 50,092,284 ha of land per year, which is roughly the size of Spain. Drawing upon the definition of a similar concept — virtual water (Hoekstra and Hung 2002), we define virtual land as the area of land resources used for the production of goods. Through introducing the concept of virtual land, we believe land resources that are traditionally considered as stationary resources can flow with anthropogenic socioeconomic activities. The largest virtual-land flows (> 3,000,000 ha/year) exist between the United States (US) to China, Brazil to China, the US to Japan, the US to Mexico, and Argentina to China. However, not all virtual-land flows necessarily result in land saving. Thus, more endeavors are needed to plan the virtual-land flows for a larger land saving at the global scale.  相似文献