可漫游的靶场虚拟地形可视化建模与实现

以某靶场虚拟地形可视化建模技术为研究对象,着重探讨了应用Terra Vista建模软件进行三维建模的基本原理和主要流程,并建立了某靶场区域地形的三维模型。并通过必要的三维模型格式转换,将所生成的地形模型应用到Virtools虚拟开发平台中,针对自动漫游和交互式漫游两种漫游方式设计实现了虚拟靶场环境漫游模块的开发和应用,为靶场虚拟试验系统的进一步开发和应用奠定了基础。     

宽带一维像雷达单脉冲跟踪建模仿真

宽带成像雷达通常采用窄带跟踪和宽带成像分时交替进行,这样势必造成雷达资源浪费.为了有效利用雷达资源,一旦窄带跟踪到目标后,雷达可以转入宽带一维成像与单脉冲跟踪.研究宽带一维像单脉冲跟踪模型,给出了高速运动目标宽带线性调频信号回波模型,根据该信号是同调频率的多分量信号的特点,将Radon模糊图变换法应用于调频率估计和一维像运动补偿,并给出了宽带一维像的测速、测距和测角模型.一维像的目标连续定位跟踪可以增加目标跟踪数据率,提高宽带雷达对机动目标跟踪能力.仿真结果验证了宽带一维像目标单脉冲跟踪技术的可行性和跟踪精度.     

基于粗糙集理论与贝叶斯网络的超视距空战战术决策

基于智能互补融合的思想,将粗糙集理论与贝叶斯网络有机结合在一起,提出了一种超视距空战战术决策的新方法.利用粗糙集理论实现对专家知识的约简和空战态势信息集的压缩,提取了超视距空战战术的最小决策信息集,基于最小决策信息集的贝叶斯网络模型可以降低网络结构的复杂性;同时利用贝叶斯网络实现了超视距空战战术的概率决策推理.最后,进行了实例分析,决策推理结果表明该方法的正确性以及在不确定环境下的有效性.     

长江河口段潮差变化研究

该文利用长江口吴淞等三个验潮站连续二十五年来的月均验潮资料,通过低通数字滤波、谱分析和交叉谱分析等方法,对长江口的月均潮差的趋势性变化和周期性变化进行了计算,并对长江口月均潮差与径流及海平面的关系进行了分析。     

关于闭值域定理的推广

给出了闭值域定理在局部凸空间中的推广     

藏红T在核酸分子表面进行长距组装的光谱特征

表征了藏红Ｔ（ＳＴ）在核酸分子表面进行长距组装的共振光散射光谱、电子吸收和发射特征。结果表明,ｐＨ７．０５、离子强度０．００４５下ＳＴ在核酸表面进行的长距组装随着ＳＴ与核酸的摩尔比（Ｒ）不同涉及到两种作用机理,当Ｒ〉１．３时,长距组装表现为紫移的减色效应和荧注猝灭,在３２８．０ｎｍ、４７２．０ｎｍ和５７２。０ｎｍ;Ｒ〈１．３３时,长距组装产物发生离解,具有红移的减色效应、荧光猝灭和微弱的共振光散射     

Demographic characteristics,seasonal range and habitat topography of Balkan chamois population in its southernmost limit of its distribution (Giona mountain,Greece)

The annual range of Balkan chamois (Rupicapra rupicapra balcanica) in Giona mountain was found to be 5502 ha, with a low population density (2 individuals/100 ha). Seasonal range patterns varied significantly, with a minimum extent in summer and a maximum in winter (30% and 79% of the annual range, respectively). Summer stress and the rutting period might be associated with the observed aggregated distributions during the summer and autumn (core areas of 28% and 22% of seasonal ranges, respectively, defined after the Fixed Kernel Density Estimator). Chamois were found to use significantly lower altitude habitats in winter (1212 m) than in summer (2223 m), and significantly steeper slopes in winter (35°); aspect was not found to have a significant effect on habitat use. Population structure consisted of kids (21%), yearlings (8%), females (35%) and males (36%). Conservation management for the species should consider poaching, livestock competition and global warming.     

Azimuth space-variant properties of BiSAR with nonequal velocities

Bistatic SAR possesses characteristic of the azimuth space-variant when the velocities of transmitter and receiver are not equal. The geometric model of BiSAR with the parallel trajectories and the nonequal platform velocities is presented. Analyzing the motion relationship of transmitter and receiver, the formula of azimuth spacevariant is derived in time domain. Via Taylor polynomial expansions, the azimuth space-variant is factorized by four terms： zero-order, first-order, second-order, and third-order term. And, their impacts on impulse response are illuminated. Some characteristics about azimuth space-variant of airborne BiSAR case are exhibited by simulation experiments, and these simulated results are coincident with the formulae of azimuth space-variant.     

基于视觉范围的自适应阈值DR模型研究

在介绍DR模型在分布交互式仿真中应用的基础上,分析了视景仿真中当前几种DR模型在解决运动实体"跳动"问题时所具有的局限性;提出了基于视觉范围的自适应阈值DR模型的数学建模理论基础和建模方法,并利用视景仿真系统Vega中的接口函数给出了相应实例;结果表明该模型不仅能有效抑制运动实体的"跳动",而且对提高整个仿真系统的效率也具有积极作用。     

四端对固体介质电容器容量的扩展频段计量

基于四端对阻抗的测量定义,开发了四端对固体介质电容器频率响应的传递测量系统,频率为10 kHz~1 MHz.测量系统由四端对电容器组、四端对宽频比率网络、四端对阻抗测量仪等组成.原理采用1∶10量值传递法,即在同一测量频率下,测量系统分别对定值电容器和被测电容器进行测量(两电容器的标称值是1∶10),将测量结果进行比较获得被测电容器的频率响应值.测量系统能严格按照四端对阻抗的测量定义进行工作,有效减小了系统误差,更适用于扩展频段四端对固体介质电容器容量的计量.