一种采用联邦EKF的分布式INS/UWB人员无偏紧组合定位方法

为了实现精确的人员定位,提出了一种采用联邦EKF的分布式INS/UWB人员紧组合定位方法.在这种模式下,将数据融合滤波器应用于UWB无线通信信道中.INS与UWB分别测量得到的参考节点到未知节点之间距离的平方值被用于预估INS的导航解算误差.在此基础上,主滤波器将各信道滤波器的预估值进行数据融合,最后得到最终的INS导航解算误差预估.实验结果显示,该方法能够准确地提供人员位置信息,与集中式滤波器相比,平均位置误差降低了10.34％左右.     

扩展有限元与遗传算法相结合的结构缺陷反演分析

建立扩展有限元法与遗传算法相结合的结构缺陷反演分析模型.扩展有限元法通过引入不连续位移模式使得网格剖分无需依赖结构内部的不连续界面.通过改变水平集函数表征结构缺陷（夹杂）的位置和大小,遗传算法在每次迭代过程中具有全局和局部搜索能力,通过评估响应测点的响应量适应度值决定是否进一步迭代.对带有单个圆形缺陷（夹杂）和多个缺陷（夹杂）的结构进行了反演分析,并就响应测点的布置进行了讨论.结果表明,建立的反演分析模型能准确地探测结构存在的单个甚至多个缺陷（夹杂）.     

具有攻击角约束的非奇异终端滑模导引律设计

为了满足导弹拦截高速大机动目标时高精度制导的需求,首先对二维平面内的弹目相对运动方程进行状态扩张,对于影响制导性能的目标总扰动采用了扩张状态观测器的方法进行动态补偿。然后在非奇异终端滑模面的基础上选取了两种滑模趋近律,设计了两种具有攻击角约束的非奇异终端滑模导引律。最后数值仿真结果表明,在观测器对扩张系统状态进行实时有效估计的前提下,针对不同的期望视线角和目标机动方式,所设计的两种导引律在满足期望的性能要求的同时,可实现导弹对目标的高精度快速打击。     

基于Gibbs矢量估计卫星轨道姿态的滤波算法研究

针对“矢量观测 陀螺”这种典型的三轴稳定卫星姿态确定系统模式,引入具有四元数优越性的Gibbs矢量作为姿态参数,提出了一种新的具有良好实时性能的轨道姿态估计方案。在方案设计中,为描述卫星轨道姿态的Gibbs矢量,推导出了基于四元数的运动学方程,并将QUEST法作为处理多矢量观测信息的压缩技术引入估计器,使得滤波修正算法得以简化。另外,针对单矢量观测情况,给出了能够加快状态估值收敛速度的改进协方差修正算法。仿真结果验证,新方案的姿态估计精度与传统的欧拉角估计法相当,而运算效率却明显高于欧拉角估计法。     

Top Quark Chromomagnetic Dipole Moment in the Littlest Higgs Model with T-Parity

The littlest Higgs model with T-parity, which is called LHT model, predicts the existence of the new particles, such as heavy top quarks, heavy gauge bosons, and mirror fermions. We calculate the one-loop contributions of these new particles to the top quark chromomagnetic dipole moment (CMDM) ΔK. We find that the contribution of the LHT model is one order of magnitude smaller than the standard model prediction value.     

Monitoring of the process of formation of epitaxial films with the use of ultrasoft x-ray spectroscopy

The distinctive features of the atomic and electronic structure of thin surface layers of substances in the process of formation of epitaxial silicon films on silicon are studied using the procedures of reflection and scattering of ultrasoft x-ray radiation. The angular distribution of the scattered x-ray radiation (the scattering indicatrices) and the near fine structure of SiL_2,3 spectra of reflection are investigated. The assumption of the sensitivity of the observed peak of anomalous scattering (the Yoneda peak) of x-ray radiation to the presence, in the surface regions of the materials, of extended double-boundary defects, the defects of packing, grain boundaries, dislocations, etc. is made. It is shown that the experimental procedure used makes it possible to obtain information on the surface layers of substances. Translated from Zhurnal Priklaldnoi Spektroskopii, Vol. 67, No. 4, pp. 496–498, July–August, 2000.     

Single Production of Top Quark via e-γ Collision in Left-Right Twin Higgs Model

In the context of the left-right twin Higgs （LRTH） model, we fist study single production of the standard model （SM） top quark via e-γ collisions. We find that the corrections of the LRTH model to the cross section of the process e-γ→vebt might be observed only for f ≤750 GeV and the heavy top quark mass scale M ≥500 GeV in future high energy linear e^＋e^- collider （LC） experiment with the center-of-mass （CM） energy √s = 500 GeV and a yearly integrated luminosity of ￡ = 100 fb^-1. We also consider single production of the heavy top quark T via e-γ collisions. Our numerical results show that the possible signals of the heavy top quark T might be observed via the decay channel T →Ф^＋b→tbb in future LC experiment with √s = 3 TeV and ￡ = 500 fb^-1.     

Non-minimal pp-wave Einstein–Yang–Mills–Higgs model: color cross-effects induced by curvature

Non-minimal interactions in the pp-wave Einstein–Yang–Mills–Higgs (EYMH) model are shown to give rise to color cross-effects analogous to the magneto-electricity in the Maxwell theory. In order to illustrate the significance of these color cross-effects, we reconstruct the effective (associated, color, and color-acoustic) metrics for the pp-wave non-minimal seven-parameter EYMH model with parallel gauge and scalar background fields. Then these metrics are used as hints for obtaining explicit exact solutions of the non-minimally extended Yang–Mills and Higgs equations for the test fields propagating in the vacuum interacting with curvature. The influence of the non-minimal coupling on the test particle motion is interpreted in terms of the so-called trapped surfaces, introduced in the Analog Gravity theory.     

The attractor—basin portrait of a cellular automaton

Local space-time structures, such as domains and the intervening dislocations, dominate a wide class of cellular automaton (CA) behavior. For such spatially-extended dynamics regular domains, vicinities, and attractors are introduced as organizing principles to identify the discretized analogs of attractors, basins, and separatrices: structures used in classifying dissipative continuous-state dynamical systems. We describe the attractor-basin portrait of nonlinear elementary CA rule 18, whose global dynamics is largely determined by a single regular attracting domain. The latter's basin is analyzed in terms of subbasin and portal structures associated with particle annihilation. The conclusion is that the computational complexity of such CA is more apparent than real. Transducer machines are constructed that automatically identify domain and dislocation structures in space-time, count the number of dislocations in a spatial pattern, and implement an isomorphism between rule 18 and rule 90. We use a transducer to trace dislocation trajectories, and confirm that in rule 18, isolated dislocation trajectories, as well as a dislocation gas, agree extremely well with the classical model of annihilating diffusive particles. The CA efficiently transforms randomness of an initial pattern ensemble into a random walk of dislocations in space-time.     

Higgs Boson Decay into Two Gluons and a <Emphasis Type="Italic">Z</Emphasis> Boson

Results for the one-loop calculation of the decay width Γ(H→ggZ) in the standard model with Higgs boson masses in the range 115 GeV<m _H <2m _W are presented. We find that among all the helicity amplitudes contributing to the width only those for which the gluons have the same polarization and the Z is longitudinally polarized contribute in any significant way. The calculation includes all contributions from the second and third generations, and kinematic cuts to enhance the H→ggZ signal. Compared to the width of H→gg, we find Γ(H→ggZ)/Γ(H→gg)≲10⁻⁴.