“水下空间”视景仿真软件模块的开发研究

目前版本的Vega只能通过海洋模块仿真海面以上的场景 ,如波浪、舰船尾流等。本文分析了Vega的组成结构及工作原理。在此基础上 ,针对水下空间效果如光影、透明度、气泡等仿真的需求 ,自主开发了“水下空间”模块 ,并嵌入到Vega中。解决了Lynx关键字配置文件、GUI配置文件和Lynx插件动态链接库的开发设计等一系列相关技术 ,以VC ++6 0为开发工具 ,利用OpenGL图形库编程开发了实现模块各项功能的动态链接库。其中以“水下透明度”的实现为例 ,论述了图形学算法及程序设计方法。应用结果表明 ,该模块便捷易用 ,效果逼真 ,适用于水下空间的视景仿真。

武汉市水下空间的开发利用探索

武汉市水域众多,城市环境特殊。为解决武汉市由于天然江河湖面的分隔造成的城市发展难题,解决城市高效、集约和可持续性发展问题,提出了开发水下建筑空间的构想。对比国内外的相关发展状况和武汉市开展地下空间的建设现状,讨论了武汉开展水下空间建设的可行性,提出了武汉市水下空间开发利用的开发原则、开发技术手段以及典型的开发事例。并对开发水下空间将会面临的主要困难作了基本的分析,能对今后相关的建设研究提供一种新的思路。

深水明渠附着水下空间体的水动力特性与体型优化

大型长距离输水明渠边坡衬砌破坏后,受供水保证率制约通常只能不停水修复,而现有施工技术在深水渠道中难以使用,寻找快速环保地进行明渠不停水修复已成为亟待解决的重大技术难题。突破传统施工围堰概念,提出使用“水下无底拱穹结构”作为大型明渠不停水修复的施工平台。以南水北调中线干渠某渠段为例,采用数值模拟与物理模型验证相结合的方法,开展了空间体的水动力特性及体型优化研究。首先基于水下空间体的构造与选定的约束条件,利用Rhion和Flow 3D软件搭建了研究渠段的三维水动力学模型;分别对设计的三种体型水下空间体进行了水动力数模计算,分析了渠道流态与流场、断面流速分布、回流强度、壅水及阻力损失等水力要素的特征,计算了空间体的绕流阻力,对比总结了三种体型空间体的水动力学特征。结果表明,半椭圆形水下空间体绕流阻力较小,对渠道过流能力影响最小,可考虑作为水下空间体的应用选型。本文的研究为渠道内快速开展不停水维修提供了新思路与技术参考。

Jellyfish水下空间站设计

本设计Jellyfish水下空间站,作为仿水母的隐身、模块化的水下空间站系统,可应用在作战海域和安全海域。在作战海域里,诱饵群可反鱼雷,保护母体安全;母体无法规避危险时,控制舱可与母体分离,产生超空泡,点燃多级火箭助推系统快速逃离。在安全海域,变形、可旋转的双面太阳能电池板可补充能量。

水上水下空间可视化在地质遗迹开发中的应用

地质遗迹具有不可再生性,人类对地质遗迹资源的利用是通过对地质遗迹资源的开发和保护过程实现的。本文通过无人机倾斜摄影测量和无人船搭载多波速测深系统,获取了东莞市石排镇红石山燕岭古采石场遗址公园水上水下一体化实景三维模型。通过对典型区域的处理分析,实现了地质公园后期开发的预判,为地质遗迹保护、地学生态重建、地球科学科普以及地学旅游等提供基础数据和科学依据,对地质遗迹的可持续发展具有工程意义。

水下空间中的光学高精度双向时间比对

为探寻水下空间导航定位授时服务的新途径,进一步提升水下空间授时精度,提出一种水下空间中的光学双向时间比对方法,阐述其基本原理和系统组成,利用激光二极管、光束准直器和反射镜等搭建基于玻璃水池的实验系统。最终,实验系统的时间比对结果峰峰值为1.6ns,系统附加时间传递抖动结果为1.05×10^(-11)s/s,6.30×10^(-11)s/10^(3)s。实验结果验证了水下空间中光学双向时间比对方案的可行性,同时纳秒量级的时间比对结果表明具有深入研究的价值。针对实验过程中存在的问题,进行了深入分析和总结,为后续工作和研究提供了理论依据。

一种新的水下立体空间WSN覆盖增强算法

当前热门的三维立体空间WSN覆盖方法应用在水下空间并不具有普适性。针对应用在水下的立体WSN覆盖方法通常存在覆盖率不高、节点移动能耗过大以及由此引起的节点能耗值差异较大等问题,结合现有的水下覆盖策略,提出一种新的基于降低节点能耗、提高水下空间覆盖率的水下空间层次化覆盖增强算法(underwater hierarchical space coverage-enhancing algorithm,UHSCA)。理论分析及仿真结果表明该策略对水下节点的精确性部署进行了性能优化,在改善节点部署过程中能量消耗均衡性的基础上降低了节点的整体耗能,水下空间覆盖率也有相应提高,对应用在水下侦察、水文监测等水下立体空间的WSN具有较强的实用性。

面向水下未知空间探测的改进RRT路径搜索算法

文中提出了一种混合RRT(rapid-exploration random tree)搜索算法.算法整体上按照全局路径和局部路径的最优试探开展同步计算.在局部路径计算层面,利用RRT^(*)算法基于周边探测数据,结合前沿点信息进行小尺度路径搜索、全局路径计算层面,利用RRT算法进行粗粒度的路径分支决策,并将已选分支的边缘信号反馈给局部路径的计算.通过RRT^(*)的重剪枝功能,能够在局部进行路径优化,而避免将其用于整体路径优化时可能带来的“选择震荡”风险.仿真实验与真实环境结果表明:将RRT*与RRT在局部和全局两种尺度上的区分使用,相较只使用RRT算法路径长度减少了16.4%.

水下大功率LED灯散热数值模拟和试验研究

为进行水下大功率LED灯散热结构的多方案优化设计,基于CFD方法对某一型自主设计、加工和制造的LED灯进行自然对流工况下的流-固共轭传热数值模拟;为验证仿真结果准确性,进行了水箱试验验证,得到的热平衡状态下测点温度值与试验结果平均相对误差为2.9%;为预测实际水下环境中LED灯的内部工作温度,进行了水下大空间中LED灯的热平衡数值模拟,比较了不同海水流速下,横向和竖向翅片对应测点的温度变化趋势,为进一步优化特定作业环境下的LED灯散热结构提供参考。

21世纪战争生存空间探索

笔者长期从事国防工程建设 ,本文概述了现代战争条件下 ,利用地下空间。

基于二次元空间环境的城市设计畅想

本文针对当今城市在快速发展中遇见不可避免的资源匮乏、社会人口密集、科技更新迅速等问题,从二次元空间的城市环境中得到启示,通过对其水下空间、上层空间和地下空间的可行性分析,探索城市设计的发展,畅谈未来城市的美好前景,旨在为当前的城市设计提供参考思路。

基于HLA的鱼雷武器系统仿真环境设计与实现

提出了一种基于高层体系结构的可扩展、可重构的鱼雷武器作战仿真开放式应用体系结构的设计方法,研制了基于软件复用技术的领域内联邦成员软件应用框架,有效地解决了时间管理策略制定及公布/定购声明的自动化、RTI与仿真应用之间接口一致性问题。同时,开发出能够提供海底地形、闪烁光斑、气泡、水下混浊及环境色等功能的水下空间Vega扩展模块,从而解决了海体、海底的三维显示。采用pRTI1.3等工具软件构建了含舰艇、鱼雷、水声装备对抗器材等10个联邦成员的分布交互仿真综合环境,初步运行表明,其具有良好的人机界面、模型可重用、实时性好等特点,能适应潜—舰,潜—潜等多种水下对抗样式的仿真要求。

Evaluation of development potential of pumped hydroelectric storage and geothermal utilization system in abandoned coal mine

Every year in China,a significant number of mines are closed or abandoned.The pumped hydroelectric storage(PHS)and geothermal utilization are vital means to efficiently repurpose resources in abandoned mine.In this work,the development potentials of the PHS and geothermal utilization systems were evaluated.Considering the geological conditions and meteorological data available of Jiahe abandoned mine,a simple evaluation model for PHS and geothermal utilization was established.The average efficiency of the PHS system exceeds 70%and the regulatable energy of a unit volume is over 1.53 kW·h/m^(3).The PHS system achieves optimal performance when the wind/solar power ratio reaches 0.6 and 0.3 in daily and year scale,respectively.In the geothermal utilization system,the outlet temperature and heat production are significantly affected by the injection flow rate.The heat production performance is more stable at lower rate flow,and the proportion of heat production is higher in the initial stage at greater flow rate.As the operating time increases,the proportion of heat production gradually decreases.The cyclic heat storage status has obvious advantages in heat generation and cooling.Furthermore,the energy-saving and emission reduction benefits of PHS and geothermal utilization systems were calculated.

水上应急救援模拟训练系统总体研究

水上应急救援是一项复杂的综合过程,为解决传统应急预案演练中所存在的不足,提出融合计算机虚拟技术的水上应急救援模拟训练系统。通过对水上应急救援模拟训练系统概念的研究,分析水上应急救援模拟训练系统的设计需求,提出水上应急救援模拟训练系统组成、架构及系统组件间交互方式,研究了舰船数字建模及数据库管理等水上应急救援模拟训练系统关键技术。针对水下环境探测作业中存在的不足,采用虚拟现实技术对水下场景进行构建,研究翻扣船舶模拟、ROV辅助作业及水下窄空间探摸等水下应急救援模拟训练子系统,实现水上应急救援人员与配套装备系统的模拟训练。

21世纪的海底、海空战场

(一)海底战场人们在开发海洋的过程中发现,海底资源及海床矿藏具有巨大的经济潜力,海洋的经济价值使人们将目光从陆地、太空转向海洋。同时,水下空间和海底也可以布置重要的战略导弹核力量,它对陆战区和海战区的作战将产生决定性的影响。因此,世界各国军队越来越多地将目光投向了诱人的海底战场。海底可以配置一系列作战系统的作战设备。在深水区,可以建设供居住的水下基地。

Influence of groundwater level change on vegetation coverage and their spatial variation in arid regions

Sampling and testing are conducted on groundwater depth and vegetation coverage in the 670 km2 of the Sangong River Basin and semi-variance function analysis is made afterwards on the data obtained by the application of geo-statistics. Results showed that the variance curve of the groundwater depth and vegetation coverage displays an exponential model. Analysis of sampling data in 2003 indicates that the groundwater depth and vegetation coverage change similarly in space in this area. The Sangong River Basin is composed of upper oasis, middle ecotone and lower sand dune. In oasis and ecotone, influenced by irrigation of the adjoining oasis, groundwater level has been raised and soil water content also increased compared with sand dune nearby, vegetation developed well. But in the lower reaches of the Sangong River Basin, because of descending of groundwater level, soil water content decreased and vegetation degenerated. From oasis to abandoned land and desert grassland, vegetation coverage and groundwater level changed greatly with significant difference respectively in spatial variation. Distinct but similar spatial variability exists among the groundwater depth and vegetation coverage in the study area, namely, the vegetation coverage decreasing (increasing) as the groundwater depth increases (decreases). This illustrates the great dependence of vegetation coverage on groundwater depth in arid regions and further implies that among the great number of factors affecting vegetation coverage in arid regions, groundwater depth turns out to be the most determinant one.

Method for Underwater Target Tracking Based on an Interacting Multiple Model

According to the requirements of real-time performance and reliability in underwater maneuvering target tracking as well as clarifying motion features of the underwater target, an interacting multiple model algorithm based on fuzzy logic inference （FIMM） is proposed. Maneuvering patterns of the target are represented by model sets, including the constant velocity model （CA）, the Singer mode~, and the nearly constant speed horizontal-turn model （HT） in FIMM technology. The simulation results show that compared to conventional IMM, the reliability and real-time performance of underwater target tracking can be improved by FIMM algorithm.

Research of Underwater Bottom Object and Reverberation in Feature Space

The critical technical problem of underwater bottom object detection is founding a stable feature space for echo signals classification. The past literatures more focus on the characteristics of object echoes in feature space and reverberation is only treated as interference. In this paper, reverberation is considered as a kind of signal with steady characteristic, and the clustering of reverberation in frequency discrete wavelet transform （FDWT） feature space is studied. In order to extract the identifying information of echo signals, feature compression and cluster analysis are adopted in this paper, and the criterion of separability between object echoes and reverberation is given. The experimental data processing results show that reverberation has steady pattern in FDWT feature space which differs from that of object echoes. It is proven that there is separability between reverberation and object echoes.

Three-Dimensional Ocean Sensor Networks:A Survey

The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research,oceanography,ocean monitoring,offshore exploration,and defense or homeland security.Ocean sensor networks are generally formed with various ocean sensors,autonomous underwater vehicles,surface stations,and research vessels.To make ocean sensor network applications viable,efficient communication among all devices and components is crucial.Due to the unique characteristics of underwater acoustic channels and the complex deployment environment in three dimensional(3D) ocean spaces,new efficient and reliable communication and networking protocols are needed in design of ocean sensor networks.In this paper,we aim to provide an overview of the most recent advances in network design principles for 3D ocean sensor networks,with focuses on deployment,localization,topology design,and position-based routing in 3D ocean spaces.

国际裁军与裁军条约初探

从古至今，军备与裁军如同孪生，始终相伴。而裁军条约又是实现裁军目标的重要法律手段。武器装备的改进，特别是核武器的出现，使国际法的调整对象和范围有所扩大，即从禁止在战争中使用某几类大规模毁灭性武器，发展到禁止试验、生产和部署以及销毁这几类武器。调整裁军活动中各国之间相互关系的那部分原则、规则和制度，有可能发展成为现代国际法的一个独立分支。