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101.
针对同平台无源传感器纯方位线关联问题,提出了一种基于变换域的局部最优航迹关联算法。该算法采用霍夫变换( Hough Transform)将方位线映射到参数域等价为点描述,将不同方位线的点描述构建成时间的离散函数,利用时间对准形成具有相同时标的点序列。对关联门限内的目标构建指数判证函数,计算满足关联门限目标的关联矩阵,并确定各航迹关联程度,采用局部寻优方法求取最优关联度的目标作为关联对。实验表明,所提算法具有较好的稳定性及时效性,有效解决了同平台多方位线关联问题。 相似文献
102.
103.
基于标签多伯努利滤波器的机动小目标检测前跟踪 总被引:1,自引:0,他引:1
标签多伯努利(LMB)滤波器在传统多伯努利滤波器基础上引入标签空间,能够实现真正意义上的多目标轨迹级滤波.文章对红外小目标的运动和量测进行建模,将标签多伯努利应用到红外小目标检测前跟踪领域.在此基础上,为了实现对运动模型时变目标的检测前跟踪,将交互式多模型(IMM)与LMB检测前跟踪算法相结合,提出IMM-LMB检测前跟踪算法.此外,给出了该算法的序贯蒙特卡罗实现.仿真结果表明,所提算法能够从输入的原始图像中直接实现轨迹级多目标检测和跟踪,且能够在线更新多模型概率,更好的适应多机动目标场景. 相似文献
104.
介绍了S模式询问机接口管理的工作原理、硬件电路和软件实现,阐述了系统的综合管理功能,分析了接口管理实现过程中的关键技术。该接口管理模块在S模式询问机上已经得到很好的验证和试验,具有性能稳定、扩展性强、功能强大等优点。 相似文献
105.
A. Szydowski B. Sartowska A. Banaszak J. Choiski I. Fija M. Jaska A. Korman M.J. Sadowski 《Radiation measurements》2005,40(2-6):401-403
The calibration diagrams, i.e. track diameters and track depths versus ion energy and etching time, as obtained for PM-355 track detector irradiated with He-ions are presented. The both detector characteristics are compared. The track etch rate is determined by two methods, as a function of the etch pit depth and the ion energy loss. 相似文献
106.
Malcolm Fairbairn 《Contemporary Physics》2017,58(1):1-24
In 2010, the MoEDAL (MOnopole and Exotics Detector at the LHC) experiment at the Large Hadron Collider (LHC) was unanimously approved by European Centre for Nuclear Research’s Research Board to start data taking in 2015. MoEDAL is a pioneering experiment designed to search for highly ionising manifestations of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics programme defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; does magnetic charge exist; what is the nature of dark matter; and, how did the Big Bang develop. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field. The innovative MoEDAL detector employs unconventional methodologies tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors – analysed offline by ultra fast scanning microscopes – sensitive only to new physics. Second, it is uniquely able to trap the particle messengers of physics beyond the Standard Model for further study. MoEDAL’s radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array. A new MoEDAL sub-detector designed to extend MoEDAL reach to mini-charged, minimally ionising particles is under study. 相似文献
107.
T. Tsuruta 《Radiation measurements》2001,34(1-6):167-170
Diallyl phthalate (DAP) resin plates were irradiated with fission fragments, and then etched in a conventional aqueous solution of KOH or a PEW solution containing ethanol, water and KOH. Etched tracks were observed and counted by using an optical microscope. The PEW solution made the fission tracks etch-pits clearer in an incomparably shorter etching time. The large and round etch-pits developed on a smooth surface were convenient for optical automatic counting. These etching characteristics of DAP in a PEW solution are suitable for quantitative analysis of fissionable materials and neutron dosimetry. 相似文献
108.
Abstract Studies concerning track shapes, etching characteristics and track density due to spontaneous fission of uranium along various crystallographic planes of apatite are represented. The studies were carried out on large complete crystals as well as on small grains of apatite belonging to various geological origins. Three track types (hexagonal, pyramidal and needle type) have been identified along various crystallographic planes. 相似文献
109.
气垫导轨在刚体转动惯量测定实验中的应用 总被引:1,自引:0,他引:1
本文介绍了一种测量刚体转动惯量的新方法。即把气垫导轨和刚体转动仪结合起来来测量刚体的转动惯量,使传统的气垫导轨实验和刚体转动惯量测定实验得以更新,提高了实验测量的精度,拓展了实验内容。 相似文献
110.
We have found the equation of the etch pit wall in solid state nuclear track detectors, as follows: where: x is the distance along a track from the point where the particle entered the detector; V(x) is the ratio of the track etch rate to the bulk etch rate; C is the integration constant that can be determined from particle penetration depth, and y is the normal distance from the particle trajectory to the etch pit wall. The equation is derived assuming the increasing track etch rate Vt along the particle trajectory.
The above equation can be used for the simulation of the track growth and calculating the major and the minor axis of the etch pit opening. The corresponding computer program was set up. The input parameters of this program are: alpha particle energy, incidence angle and removed layer: the output are track parameters. The results obtained by this method are compared with another approach given by Somogyi and Szalay (1973) and reasonably good agreement is found. 相似文献