一种新型非线性卡尔曼滤波方法

提出了一种新型非线性卡尔曼滤波方法—单形无迹求积卡尔曼滤波(SUQKF)方法,该方法通过对单形无迹卡尔曼滤(SUKF)波所用的采样点进行修正,并与高斯-拉盖尔积分准则相结合,构造了一组个数、权系数和空间分布确定的新型高阶采样点,用来进行滤波。同时指出SUKF是SUQKF的特例。将所提方法通过实验与扩展卡尔曼滤波(EKF)、容积求积卡尔曼滤波(CQKF)进行比较,结果表明:SUQKF方法滤波精度高于EKF和CQKF,且收敛速度较快,实时性优于CQKF。     

二级倒立摆的 LQG 最优控制研究

为实现二级倒立摆系统的稳摆控制,应用了线性二次高斯最优控制。根据LQG的分离原理,首先利用最优控制设计控制律,得到状态反馈;由于系统状态不能完全测得,而且系统也不可避免地会受到噪声的影响,在详细给出相应参数取值规则的基础上,采用了卡尔曼滤波对系统输出做出最优估计。最后的仿真结果表明,设计的控制器能够较好地对二级倒立摆进行稳定控制,且具有抑制噪声和抗干扰能力。     

用强化假定不连续应变实体单元分析弹性地基薄板

用强化假定不连续应变(EAS)实体单元离散弹性地基薄板,假设板上的荷载按分布力形式传递到地基中,根据半无限空间上任一点节点力与任一点处的位移关系用高斯积分法建立了地基表面分布力与节点位移关系表达式,在此基础上根据地基与板间的位移协调及静力平衡条件,建立了以板上的节点位移为未知量的有限元方程.算例分析表明,采用强化假定不连续应变实体单元分析薄板类问题是合理的,进行弹性地基薄板受力分析时考虑地基分布反力是必要的.     

光脉冲在非啁啾光纤光栅中的透射传输研究

基于均匀布拉格光纤光栅的色散特性,阐述了激光啁啾脉冲的传输演变特性,研究了工作于传输方式的非啁啾光纤光栅的透射传输特性.讨论了光源线宽、光栅长度、光栅耦合系数等光栅参数以及初始脉宽、初始啁啾等参量对补偿光纤长度的影响,通过理论计算和模拟实验研究光栅对脉冲的补偿能力.     

基于改进型灰狼算法的RFID网络规划

随着物联网技术的飞速发展,射频识别(Radio Frequency Identification,RFID)系统因具有非接触、快速识别等优点而成为了解决物联网问题的首选方案.RFID网络规划问题要考虑多个目标,被证明是多目标优化的问题.群体智能(Swarm In-telligence,SI)算法在解决多目标优化问题方面...     

带状大比例尺地形图在分带接边处的接边处理

介绍带状大比例尺地形图在分带处高斯平面上拼接的原理和方法，并编制了相应的接边数据处理程序。作业实践说明，该接边方法简便实用，计算程序正确可靠。     

Considerations of Irradiation-Induced Transient Creep in Fuel Particle Modeling*

An analytical assessment is made of the potential effects of irradiation-induced transient creep on the behavior of the TRISO-coated fuel particles of the New Production Modular High Temperature Gas-Cooled Reactor (NP-MHTGR). An analytical solution is presented for the three-layer particles, which includes transient creep in addition to steady-state creep behavior. The solution allows for evaluating the effects that transient creep has on individual particle stresses and for determining failure probabilities for particle batches using the Monte Carlo approach. Because experimental data needed to determine parameters for a transient component in a creep model for the pyrocarbons is not available, a range of possible parameter values were considered in the assessments. It was shown that transient creep measurably affects particle stresses early in the irradiation life of the particle. At that time, the hoop stress in the primary load bearing layer of the particle is in compression and the article is not vulnerable to pressure vessel failure. Later in irradiation, the effects of transient creep were typically shown to be less significant. Thus, transient creep had less than an order of magnitude effect on batch failure probabilities for prototypical NP-MHTGR fuel particles and was much less significant than steady-state creep. Whether the presence of transient creep increased or decreased the particle failure probability was dependent on the specific values used for the transient creep material properties.     

输水隧洞施工独立坐标系的计算方法

结合某引水工程隧道贯通测量,讲述了该工程独立坐标系建立的方法以及方案的选择,并编制相应的软件解算,从而保证工程的顺利实施。     

Bayesian prediction for business mortality analysis

Summary This paper is concerned with business mortality analysis in a Bayesian setting. We assume that a businessman startsN businesses at different points of time and at a certain epoch referred to as the ‘present’, the failure times of the failed businesses and the survival times of the still surviving businesses are recorded. Bayesian prediction for business mortality or survival up to a future time pointt ₀ is made under the assumptions of a Weibull business survival distribution (WBSD) and the squared error loss function (SELF). The results are extended to the situation where one of the observed times of business failure may possibly be an outlier.     

城市长大隧道集中排放的环境影响分析

随着城市交通量不断地增长,为了缓解日益突出的交通问题,许多城市大量兴建隧道,而隧道废气集中排放又对隧道周边环境空气质量产生显著影响,长大隧道的排放影响更为明显.根据高斯模型和TOP模型理论,以某长大隧道为例,对城市长大隧道竖井排放和洞口扩散的环境影响做出分析.结果表明针对相同条件,CO的环境污染贡献率要比NO2的环境污染贡献率明显偏小;同时竖井高度并不能唯一决定污染物地面浓度大小,必须保证合理的排风量;此外,洞口废气扩散的环境影响要比竖井排放更为严重,并且洞口扩散作用受风向的影响也很大.