参数
- 与 参数 相关的网络例句 [注:此内容来源于网络,仅供参考]
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The numerical ex-periment has shown that the number of iterations depends significantly on the positiveparameterα,β. But, in general, it is di?cult to choose a proper parameterα,β. Thuswe propose new self-adaptive alternating direction method which adjusts the scale pa-rameter automatically per iteration based on the message of the iterates. We have provedthe convergence of the method under mild assumptions.Finally, we present some numerical results.
对于我们提出的新交替方向法,数值实验表明,迭代的步数与时间与所取的参数α,β有关,然而我们很难去选择一个合适的参数α,β,因此我们提出新自适应交替方向法,对其中的参数α,β进行自适应调整,这种自适应算法根据每步迭代信息自动地调整参数α,β,并证明了算法的收敛性。
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The examples indicate that the unknow parameters can be estimated faster and more accurately with the proposed objective function and SPSO, the solving procedure relies less on the augmented jacobian matrix, and the mean estimated values are close to the parameter truth values.
仿真算例表明:应用该文修正项和SPSO方法,能快速准确的估计线路参数,并提高参数估计精度和降低对量测系统参数可估计性的要求,估计均值更接近参数真值。
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The common method, that all strong-correlation terms of the model are eliminated, can bring the loss in the engineering application, so the new method is proposed that the identified model reserves some correlation. The augmented matrix A is constructed by the outputΔW and the matrix S. The"determinating order based on ratio of determinant"is brought out to screen the strong-correlation terms in the structure identification. The latent root estimation is improved in screening the eigenvalues and eigenvectors. Thus the estimation precision is improved greatly.The consistence check of guidance instrument error coefficients of flight test and ground test is the purpose of flight experiment. The causes of inconsistency of the two models are analyzed. The hypothesis test of linear regression model based on F statistics is proposed to check the consistence.Finally, the instability of error coefficients is probably caused by the change of the flight environments, therefore, the relation between the error coefficients and flight environment is analyzed. The approach is presented to identify SINS guidance instrument error models and compensate the error in the segmented sections corresponding to the change of vertical acceleration of aircraft.
在结构辨识中,常用的方法由于将模型中的强相关项全部剔除而给工程应用带来损失,因此,本文提出了新的有益思想,即在保留一定相关性的基础上进行辨识:将输出向量ΔW与环境函数矩阵S构成增广矩阵A,然后采用"比定阶行列式"来剔除相关向量的方法,这样既可以尽可能多地保留了对落点影响大的强相关参数,又可以对落点影响小的强相关参数给予剔除;在参数估计中,改进了特征根估计中特征根和特征向量的筛选方法,提出"近零"准则,从而大大提高了参数估计的精度;再者,鉴于天地模型"一致性"检验是飞行试验和SINS制导工具误差系数分离的主要目的,因此,本文又深入分析了造成天地模型不一致的原因,提出了采用基于F统计的线性回归模型假设检验方法来进行捷联制导工具误差模型的天地"一致性"检验;最后,鉴于飞行环境剧烈变化可能会对惯性仪表误差系数稳定性带来一定的影响,因此本文深入地分析了SINS制导工具误差系数与外界环境的关系,提出了基于过载变化大小的分段辨识和分段实时补偿的算法。
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A theoretical model is built to investigate the simulation of the infrared characteristic of the metal structure with the PCM false target.Structure parameters of the PCM false target that suit for the simulation are investigated numerically.According to the results,further request on the improvement of the thermal conductivity of PCM is presented.An experimental platform is built and the numerical model is validated experimentally.Three key thermal characteristic components of the false tank(barbette,wheel and front armor plate) are manufactured and tested,and good results are obtained.A method for the thermal conductivity enhancing of PCM by using aluminum fins is studied,the influence of the structure parameters of PCM plates to the simulation effects are investigated numerically,and the reasonable configuration parameters of the PCM plates used to simulate the steel plates of different thickness are obtained.In the study of the application of heat convection method in IR false target,a passive infrared simulation system is designed to simulate the infrared characteristic of metal constructions.The system is made up of pipe-plate,pump,receiver,and working fluid.
在相变材料应用于红外示假的研究中,通过数值模拟,研究确定了适用于制作假目标的相变材料各物性参数的范围,分析了相变材料制作假目标的可行性,并根据所得结果,选取石蜡为研究对象,建立了相变材料模拟金属构件红外特征的理论模型,研究了适用于模拟各金属构件红外特征的相变材料假目标的相关结构参数,得出了相变材料假目标模拟各金属构件红外特征的理论结果,并对相变材料的导热系数这一物性提出了进一步的改进要求;搭建了假目标实验平台,验证了所建理论模型的准确性;以坦克假目标为研究对象,制作了炮塔、负重轮和前上装甲板三个坦克假目标的关键红外热特征部件,并进行了野外实验,取得了较好的结果;以添加铝肋片作为改进相变材料导热能力的手段,理论研究了此类导热增强型相变材料的相关结构参数对模拟效果的影响,得出了模拟不同厚度钢板红外特征的导热增强型相变材料的结构参数及模拟效果。
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Then,it discusses the method of Parametric Design of E·P and Boolean operation in the parametric design.
阐述了建立电除尘器参数化模型的意义,介绍了ANSYS参数化设计语言APDL、ANSYS命令流及电除尘器的结构特点,并讨论了电除尘器参数化建模的方法及参数化建模中的布尔运算。
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Decision properties are derived from constraints and are primitive data representing the status of design objects Performance properties calculate decision properties and the domain are bounded by design constraints.
决策参数是从限制条件中抽象出来的数据,代表设计对象的属性或状态;表现参数是对决策参数的计算和度量;限制条件规范及限制表现参数的域值,可视为类不变量,每个类对象都必需满足之。
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This paper establishes the relations between braided parameters and geometry parameters and it is valid by experiments.
并建立了编织工艺参数和几何结构参数的关系,通过实验验证,证明了工艺参数和几何结构参数之间关系的正确性。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component. For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper. For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space state informatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision. Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component.For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material .distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper.For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space stateinformatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision.Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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The performance function and constraint equation in calculus of variations were constructed by analyzing input and output equations of the system containing parameters to be estimated. The traditional parameter estimation problem could be transformed to that of least squares estimation.
通过分析包含待估参数的系统输入输出方程,构造变分法中的性能范函和约束方程,将传统的参数估计问题化为带约束条件的最小二乘估计问题;利用拉格朗日乘子法,分析参数估计方程,得到参数的最优估计。
- 推荐网络例句
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By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.
到它被攻陷的时候,里面多数的犯人是写了反对政府贪污文章的作家。
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The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.
在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色,卵在发育96h后卵基本全部孵化。
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There was a conflict between plebs and patricians in ancient Rome in 494BC.
在公元前494年,罗马发生了一次平民反对贵族的斗争。