Blocking Probability of Noninteger Groups with Trunk Reservation

A model for computing the blocking probability in circuitswitched networks operating with trunk reservation is extended to the case of noninteger trunk numbers. This generalization is required if the model is to be used in network optimization algorithms, which are generally evaluated over the reals. A simple extension is first presented, and shown to be numerically unstable over some values of the parameters. A recursive approach is then explained that is both robust and efficient for an integer number of reserved trunks and arbitrary parameters. The model is finally extended to arbitrary trunk numbers, and an efficient and robust algorithm is proposed.     

Estimation of linear parametric models using inverse filtercriteria and higher order statistics

Considers the problem of estimating the parameters of a stable, scalar ARMA (p, q) signal model (causal or noncausal, minimum phase or mixed phase) driven by an i.i.d. non-Gaussian sequence. The driving noise sequence is not observed. The Wiggins-Donoho (1978, 1991) class of inverse filter criteria for estimation of model parameters are analyzed and extended. These criteria have been considered in the past only for moving average inverse filters. These criteria are extended to general ARMA inverses. Computer simulation examples are presented to illustrate the proposed approaches     

An accurate charge control approach for modeling excess phase shiftin the base region of bipolar transistors

The conventional charge control approach is extended to enable the accurate determination of excess phase shift in the ac common-emitter current gain of bipolar transistors arising from distributed stored minority carrier charge in the neutral base. Generalized expressions, valid for transistors with arbitrary impurity profiles and position-dependent transport parameters, are presented from which the excess phase shift can be determined solely from device structure and process data. The ac model parameters which result from the extended charge control approach are used in an existing high-frequency compact nonquasi-static bipolar model which is suitable for SPICE simulation     

动力型锂电池SOC与SOH协同估计

锂电池及其应用近年来逐渐成为研究热点。以提高电池管理系统(BMS)对电池荷电状态(SOC)和健康状态(SOH)的估算精确度为目标,在建立二阶Thevenin等效电路模型基础上提出一种能在线协同估算电池荷电状态和健康状态的改进扩展卡尔曼滤波算法。通过分阶段脉冲放电实验,并利用最小二乘法求得模型参数。在动态应力测试工况(DST)下借助Matlab对比分析了改进扩展卡尔曼算法在SOC和SOH估计精确度、错误初值时算法收敛性、算法复杂度等方面的性能。实验表明,利用该算法可以精确估计出各采样点处的SOC和SOH,误差低于1%;且在初值不准确情况下,运行算法可快速收敛至真值附近,算法估算结果的准确性与模型参数的微调无关,鲁棒性较好。     

Extended charge-control model for bipolar transistors

In modeling bipolar transistors the charge-control concept provides a means to predict dynamic behavior from a detailed knowledge of the steady state. As such, it is a first-order approximation lacking accuracy. It is shown that a considerable improvement can be obtained when the concept is extended by allowing time delays in the relations between controlling charges and terminal voltages and currents. It suffices to introduce two delays whose magnitudes can be determined or estimated from the steady-state solution. The increased range of validity of the extended charge-control model is demonstrated in detail, by confronting it with a rigorous model and comparing small-signal parameters.     

散射环境下宽带移动通信衰落信道扩展模型

介绍了采用高精度信道测试设备进行室外100 MHz宽带无线信道测试;针对传统多径衰落无线信道测量模型中易忽略的漫散射效应,提出了包含漫散射指数衰落特性的宽带无线信道扩展模型;基于实测数据提取了相应的扩展模型参数和更准确的时延特性,验证了宽带扩展模型的有效性和必要性.宽带移动通信信道扩展模型能够高精度地描述宽带信道衰落特性,对第四代宽带移动通信系统的设计乃至实际散射环境下的现场试验均有重要意义.     

Effect of multiple scattering on the phase signature of wet subsurface structures: applications to polarimetric L- and C-band SAR

We propose a two-layer integral equation model (IEM) model including multiple-scattering terms to reproduce the phase signature of buried wet structures that we observed on L-band synthetic aperture radar (SAR) images. We have good agreement between the extended (single+multiple scattering) IEM model and previous results obtained using a single-scattering IEM model combined with finite-difference time-domain simulations. We show that the multiple scattering not only significantly influences the copolarized phase difference but can also be related to the soil moisture content. In order to assess the validity of our extended model, we performed radar measurements on a natural outdoor site and showed that they could be fairly well fitted to the extended model. A parametric analysis presents the dependence of the copolarized phase difference on roughness parameters (rms height and correlation length) and radar parameters (frequency and incidence angle). Our study also shows that the phase signature should allow detection of buried wet structures down to a larger depth for C-band (3.8 m) than for L-band (2.6 m). This signature could then be used to map subsurface moisture in arid regions using polarimetric SAR systems.     

An extended Tanh law MOSFET model for high temperature circuitsimulation

The Tanh law MOSFET model proposed earlier by Shousha & Aboulwafa (see ibid., vol. 28, no. 2, p. 176-9, 1993) is extended to predict the temperature dependence of the drain current by including the temperature dependence of the threshold voltage and the mobility. The model requires fewer temperature dependent parameters compared to SPICE level2 model. The extended model shows good agreement between measurement and simulation of devices with different device geometries over wide temperature range (27-200°C)     

GTD模型在目标谐振区散射机理建模中的适用性分析

为了弄清光学区目标散射模型GTD模型在目标谐振区散射机理分析中的适用性,该文提出了一种基于匹配追踪的GTD参数提取新算法。在此基础上,利用该算法和Li 的最小二乘拟合方法,分别使用GTD模型,Altes模型以及扩展了的Altes模型对导体球体谐振区理论散射场和实测有限长柱体的超宽带散射场进行了分析,并通过对提取的散射类型参数与拟合结果的对比分析给出了几点有意义的结论。     

湍流大气中部分相干光二阶统计特性的三参数模型及其应用

激光在强湍流中的传输以及斜程传输问题是随机介质波传播研究中的热点,也是难点。文中尝试建立一个可以在任意湍流环境下通用的激光传输二阶矩演化模型。首先利用广义惠更斯-菲涅尔原理及球面波结构函数的二次近似推导了高斯-谢尔波束在大气湍流中传输时的互相干函数表达式。建立了波束互相干函数的三参数模型,得到了三参数的递进公式。利用三参数迭代法计算了部分相干波束在强湍流中及斜程传输时的等效波束半径及相干长度。计算结果证明了在强湍流中,相比于直接利用广义惠更斯-菲涅尔原理的计算结果,迭代法得到的等效半径较小,而相干长度较大。在斜程路径上,上行与下行传输激光的统计特性是不同的。     

From point defects to dislocation loops: A comprehensive modelling framework for self-interstitial defects in silicon

An atomistic model for self-interstitial extended defects is presented in this work. The model is able to predict a wide variety of experimental results by using a limited set of assumptions about the shape and emission frequency of extended defects, and taking as parameters the interstitial binding energies of extended defects versus their size. The model accounts for the whole extended defect evolution, from the initial small irregular clusters to the {3 1 1} defects and to the more stable dislocation loops. It predicts the extended defect dissolution, supersaturation and defect size evolution with time, and it takes into account the thermally activated transformation of {3 1 1} defects into dislocation loops. Moreover, the model is also used to explore a two-phase exponential decay observed in the dissolution of {3 1 1} defects.     

A simple diode model with reverse recovery

The basic diode charge-control model used in SPICE is extended to include reverse recovery. The model is derived from the semiconductor charge transport equations. The diode charge transport equations are simplified using the lumped charged concept of Linvill, and the model is demonstrated on the Saber simulator for simple inductive and resistive load circuits. The two model parameters, diode lifetime and diffusion transit time, can easily be determined from a switching waveform     

基于双重扩展卡尔曼滤波器的共轴跟踪技术研究

为了解决光电经纬仪由于机动目标运动模型不准确而引起的跟踪精度下降的问题,采用了单隐层前向神经网络(SLFNs)进行建模,提出了基于状态参数双重扩展卡尔曼滤波估计的共轴跟踪控制技术。仿真与实验结果显示,对83.33sin0.6t的等效正弦目标的速度估计最大误差为0.070 9()/s,跟踪精度为2.42';对旋转周期为4.5 s的光学动态靶标的跟踪精度达到2.96'以内。由此可见,所建立的模型与机动目标实际模型匹配,双重扩展卡尔曼滤波器(DEKF)能快速跟踪和估计状态参数。与传统控制方法相比,提出的方法具有更高的跟踪能力,能有效提高系统的跟踪精度。     

经颅磁声刺激下分数阶扩展Hindmarsh-Rose神经元放电特性分析

该文基于分数阶扩展Hindmarsh-Rose(HR)神经元模型,对其在经颅磁声刺激(TMAS)影响下的放电模式和放电频率进行了分析研究.作为神经元的外部刺激输入,具有不同磁声参数的经颅磁声刺激产生的交变电流会对神经元的放电特性产生不同的影响.通过对不同磁感应强度、超声强度以及超声频率下神经元的膜电位曲线以及以磁声参数...     

基于PPP模型的多扩展目标跟踪的JPDA算法研究

针对多扩展目标跟踪问题,提出了基于泊松点过程（Poisson Point Process, PPP）模型的多扩展目标跟踪的联合概率数据关联（Joint Probabilistic Data Association, JPDA）算法。首先,采用PPP对扩展目标进行测量建模,其次以“多对一”关联模型思想提出一种的JPDA算法,从而计算运动目标的当前有效量测的边缘关联概率,然后结合该边缘关联概率以概率数据关联（Probability Data Association, PDA）的方式分别更新每个扩展目标的运动参数和形状参数向量,最后通过仿真实现了当扩展目标相互靠近或出现交叉时的跟踪。实验结果表明,在高杂波环境下,本文所提出的算法在计算时间和跟踪稳定上具有较明显的优势。      

Modeling and estimation for patient controlled analgesia of chronicpain

An existing mathematical model of the patient and the pain in patient controlled analgesia is extended to account for the potent metabolite morphine-6β-glucuronide and to characterize chronic pain. Nominal population parameters characterizing pain and analgesic effect are tuned to make the model match observed clinical behavior. The model is used to design an on-line estimator generating state estimates which should be suitable for use in a stochastic PCA algorithm delivering a self-adjusting continuous infusion     

Inference of nonlinear state-space models for sandwich-type lateral flow immunoassay using extended Kalman filtering

In this paper, a mathematical model for sandwich-type lateral flow immunoassay is developed via short available time series. A nonlinear dynamic stochastic model is considered that consists of the biochemical reaction system equations and the observation equation. After specifying the model structure, we apply the extended Kalman filter (EKF) algorithm for identifying both the states and parameters of the nonlinear state-space model. It is shown that the EKF algorithm can accurately identify the parameters and also predict the system states in the nonlinear dynamic stochastic model through an iterative procedure by using a small number of observations. The identified mathematical model provides a powerful tool for testing the system hypotheses and also for inspecting the effects from various design parameters in both rapid and inexpensive way. Furthermore, by means of the established model, the dynamic changes in the concentration of antigens and antibodies can be predicted, thereby making it possible for us to analyze, optimize, and design the properties of lateral flow immunoassay devices.     

电子产品加速寿命试验的一种优化设计

在两个未知参数的加速方程中,设定一个约束条件,以MLE渐进方差最小为准则。给出了指数分布（电子产品寿命数据）下k≥3个应力情况失效数据分配的最优设计。     

Améliorations du modèle pour le calcul des atténuations dues à la pluie sur un un trajet Terre-espace et étude de sensibilité aux paramètres

In a recent paper, a rain cell model, initially aimed at predicting attenuations over horizontal paths, has been extended to slanted paths. The present study investigates problems which arise when applying the model to cases considered in little detail previously. Moreover, a sensitivity study is carried out and allows a better insight in the way the model operates in current conditions, as well as an assessment of the sensitivity of the results with respect to specifying parameters.     

An extended Gummel-Poon model for an extreme range of temperature

An extended Gummel-Poon model qualified for extreme temperature requirements (-40/spl deg/C/spl les/T/spl les/150/spl deg/C) is presented. Comparing measurements and SPICE calculations of a bipolar transistor, the improvement of the modified model is demonstrated. The physical parameters determining the current gain characteristics are discussed.