查询词典 parameter estimation

Estimations of effective parameter in heterogeneous media: Firstly, we clarify the concept of the effective parameter and address the problems of parameter estimation by traditional pumping test. Secondly, we present two estimation approaches (i.e., distance-drawdown and spatial moment analyses) for Seff and Teff, which are consistent with Theis' homogeneous aquifer assumption.

本文探讨的内容主要分两大部分：(1)空间异质性孔隙介质有效参数的推估方法：主要探讨内容包括重新思考有效参数的定义及其观念，探讨传统抽水试验推估异质性含水层有效参数的一些问题，其次提出估计异质性地下水系统有效参数两个合理方法：泄降-距离曲线分析和泄降分布的空间矩分析，并以数值实例解释其合理性，文中藉由分析数值模拟的结果探讨说明该问题。

The nonlinearity and discrete gradient inherited in CAViaR model is a conundrum for parameter estimation. We take the asymmetric Laplace distribution with scale parameter as the error process; indicate the variance has a minimum positive value when the scale parameter is a constant, conflicting with the distribution of real financial data. Further we estimate the parameters of indirect TARCH-CAViaR model base on Bayesian framework and Markov chain Monte Carlo method. The optimal scale parameter can also be obtained by Markov chain Monte Carlo method.

CAViaR一般模型中递归分位回归方程的非线性和非连续可微性是参数估计的一个难题，基于含有尺度参数的不对称拉普拉斯分布作为误差过程，指出将尺度参数固定为常数会导致不对称拉普拉斯分布随机变量的方差存在最小正值的限制，与实际金融数据分布不符；进而提出采用贝叶斯分析和马尔科夫链蒙特卡罗模拟方法，估计间接TARCH-CAViaR模型的参数，并可获得尺度参数的合理估计。

In this paper,results of Markov chain are used under the circumstances of the automaton model which belongs to logical level of Discrete Event System to analyze the steady states and transient states of the Markov model of DES,respectively based on four conditions of discrete-time parameter and continuous-time parameter.A simpler decision rule of system ergodic property which applies both to the conditions of discrete-time parameter and continuous-time parameter is presented through an example.The transient states of DES which under the condition of continuous-time parameter are analyzed and computed based on Kolmogorov backward equation or forward equation.

利用马尔科夫链的结果，在离散事件系统逻辑层次的自动机模型基础上，对DES的Markov模型的稳态和暂态特性，分别从时间参数连续和离散的情况下，分四个情况进行了分析，通过实例对系统遍历性提出了一条更简单的且在连续和离散时间参数情况下都通用的判定规则，并利用Kolmogorov向后或向前方程，对连续时间参数DES的暂态特性进行了分析和计算。

In order to improve the reliability of the nuclear Generating Sets and the stabilization of the power system, prevent the long time low frequency oscillation caused by the disturbed of the outside electrical net, assured improving the stabilization margin of the nuclear generating sets in the precondition of enough transient stability, validate the sensitivity of the parameter to the damping of Generating Sets of the MEC5220 digital excitation adjustor produce in Japan that used in the Second Project of Qinshan Nuclear Power Plant, confirm the parameter rationality of the digital excitation adjustor, optimize the parameter of PSS, in this paper, we put up a in-depth study to the principle of MEC5220 digital adjustor produce in Japan by the PSS/E software that develop by the PTI Company in the USA, completed the modeling of the excitation adjustor, PSS, generator, excitor, described the performance of this excitation adjustor, analyzed the essential reason that caused the low frequency oscillation, illuminated the factor that influence the damping characteristic of the MEC5220 digital excitation adjustor. Based on model and emulate, this paper optimized the primary parameter of the excitation adjustor, make a reasonable regulation to the PSS parameter.

为提高核电机组的运行可靠性和接入系统的安全稳定性，防止在外电网的干扰下核电机组发生长时间的低频振荡，保证机组在暂态稳定的前提下提高其稳定裕度，验证秦山核电二期核电机组所配日产MEC5220型数字式励磁调节器参数对机组阻尼的灵敏性，确定数字式励磁调节器的参数的合理性，优化PSS整定参数，本文利用美国PTI公司研发的PSS／E软件对日产MEC5220型数字调节器的原理进行进行了深入细化的研究，完成了励磁调节器、PSS、发电机、励磁机的建模，描述了该型励磁调节器的性能，分析了产生低频振荡的根本原因，阐明了影响阻尼特性的因素。

So it holds a ideal ability to anti-interference and has 2 scalar level resolution in location and measuring velocity than traditional radio induction technology. And the channel composed of the new radio induction system for communication is different from the parameter-constant channel and the traditional parameter-changing channel, its parameter is decided by the mutual induction between its antenna and induction-cable, by the location of its antenna, by the signal frequency passing through, its parameter has nothing to do with the time parameter.

而且，由新型无线感应系统组成的信道既不是恒参信道，也不是一般目前所知的变参信道，其信道传递函数的幅值只与信号的频率有关，与系统中天线和感应电缆之间的互感和天线的位置有关，而与时间无关，其信道传递函数的相位只与天线的位置有关，而与时间无关，由新型无线感应系统组成的信道是一种不随时间变化的新型变参信道。

The method controls a whole operation process mainly through a PC, wherein the PC transmits a preset polarity parameter and an electric testing parameter to a PCI control module, and a light test parameter to a light test module, while the PCI control module transmits corresponding parameter signal to a polarity detection module and an electric test module; moreover, a fixture is started to carry out parameter testing, and then the data tested by the fixture is transmitted to the PC.

本发明主要是通过PC机来控制整个操作过程，其中PC机把预设极性参数、电测试参数传输给PCI控制模块，和由PC机把光测试参数传输给光测试模块，而PCI控制模块再把相应的参数信号传输给极性检测模块和电测试模块，并启动夹具进行参数测试，再把由夹具测试所得数据传输给PC机。

On this basic, we use intelligent decision technology based on case reasoning to NC cutting parameter decision and analysis. According the characters of NC cutting parameter decision, we take decision based on NC techniques rule, cutting case matching based on similar degree and cutting parameter correcting based on rules to design and realize system. Combining many field technologies, it makes a unique method to resolve NC cutting parameter problem. This design pattern is a new thinking for NC cutting parameter process.

在此基础上，本文将基于实例推理的智能决策技术用于数控切削参数的决策分析，根据切削参数决策判断过程的特点，分别按照基于规则的切削加工方案决策—基于相似度的切削参数实例匹配—基于规则的切削参数实例修正的设计思路进行了系统设计和实现，多个领域的技术紧密结合，形成解决切削参数难题的独特方法，开辟了数控切削参数处理的新思路。

When the random error is not subject to normal distribution, the least absolute deviation estimation is superior to the least squares estimation. In addition, the robustness of the least absolute deviation estimation is also better than that of the least squares estimation.

在随机误差不服从正态分布的问题中，最小一乘估计的统计性能优于最小二乘枯计；另外，最小一乘估计的稳健性更强。

Limit theorems, asymptotic methods, asymptotic efficiency and efficiency bounds for estimation, maximum likelihood estimation, Bayes methods, asymptotics via derivatives of functionals, sample-based estimates of variability:; robustness; estimation for dependent data, nonparametric estimation and testing.

高级统计推断理论：极限理论，渐进方法，渐进有效和估计的效率，加大似然估计，贝叶斯方法，泛函数的微商渐进性，基于样本的估计：(bootstrap 和 jackknife方法)；稳健性；独立数据的估计，非参数估计和经验。

STAT 581 Advanced Theory of Statistical Inference (3) Limit theorems, asymptotic methods, asymptotic efficiency and efficiency bounds for estimation, maximum likelihood estimation, Bayes methods, asymptotics via derivatives of functionals, sample-based estimates of variability:; robustness; estimation for dependent data, nonparametric estimation and testing.

高级统计推断理论：极限理论，渐进方法，渐进有效和估计的效率，加大似然估高级统计推断理论：计，贝叶斯方法，泛函数的微商渐进性，基于样本的估计：(bootstrap 和 jackknife 方法)；稳健性；独立数据的估计，非参数估计和经验。

Objective:To explore the feasibility of laparoscopy in diagnosing and treating of abdominal diseases.

目的：探讨腹腔镜用以诊断腹部外科疾病及选择治疗方案的可行性。

The lifetime of nylon 1010 and nylon 1010/POSS composites decreased with increasing temperature.

热重-红外联用分析表明尼龙1010在氮气气氛下的降解产物主要为小分子的低聚物，POSS并不改变尼龙1010降解产物的组成。