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Effects of sleep bruxism on functional and occlusal parameters:a prospective controlled investigation 被引量:5
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作者 Michelle Alicia Ommerborn Maria Giraki +5 位作者 Christine Schneider Lars Michael Fuck Jrg Handschel Matthias Franz Wolfgang Hans-Michael Raab Ralf Schfer 《International Journal of Oral Science》 SCIE CAS CSCD 2012年第3期141-145,共5页
This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigat... This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm (s.d., 0.69 mm) in the sleep bruxism group and a mean slide of 0.4 mm (s.d., 0.57 mm) in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects (Mann-Whitney U-test; P=O.O08). However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive caoacitv of the stomatognathic svstem into future investigations. 展开更多
关键词 dental occlusion functional parameters prospective study sleep bruxism
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Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart Ⅱ: Material Function with Nagai Chain Constraints and Determination of Their Parameters from Flow Curves 被引量:3
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作者 Mingshi SONG Sizhu WU and Xiuyun DU(Research Institute of Polymeric Materials, Beijing University of Chemical Technology, Beijing, 100029, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第2期141-152,共12页
An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the de... An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the dependence of ηo and τt on M3.4 were derived from the theory of non-linear viscoelasticity with constraints of entanglements for polymer melts and substituted into the Oldroye-Walters-Fredickson constitutive equation. An integral constitutive equation for polymer melts was consequently obtained. Some material functions of the constitutive equation related to certain 'test flow' are examined as follows : (1) simple steady shear flow; (2) steady elongation flow; (3) small-amplitude oscillatory shear flow; (4) stress growth upon the inception of steady shear elongation flow; (5) stress relaxation (modulus and compllance). These theoretical relations for simple steady shear flow were compared with experimental data from our laboratory and references for various polymer melts and concentrated solutions. A good agreement between the theory and experiment was achieved. 展开更多
关键词 LDPE Material function with Nagai Chain Constraints and Determination of Their parameters from Flow Curves Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart Flow GR
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PARACRYSTAL STRUCTURE PARAMETERS STUDIES IN LDPE/EPO BLENDS WITH VARIANCE-RANGE FUNCTION METHOD
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作者 Huan GAO Bao Quan YANG Zhi Shen MO Changchun Institute of Applied Chemistry,Academia Sinica,Changchun,130022Zhong Cheng HU The Center of Analysis and Measurement,Northeast Normal University,Changchun 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期321-322,共2页
X-ray diffraction line profiles of low density polyethylene(LDPE)/ (ethylene-propylene-octene-1)copolymer(EPO)blends have been analyzed with variance range function method.Theories for determining the microparacrystal... X-ray diffraction line profiles of low density polyethylene(LDPE)/ (ethylene-propylene-octene-1)copolymer(EPO)blends have been analyzed with variance range function method.Theories for determining the microparacrystallite size and the distortion parameter from single reflection have been described,and the value of these two parameters at (110)and(200)directions have been determined. 展开更多
关键词 EPO PARACRYSTAL STRUCTURE parameterS STUDIES IN LDPE/EPO BLENDS WITH VARIANCE-RANGE function METHOD LDPE
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Introducing the nth-Order Features Adjoint Sensitivity Analysis Methodology for Nonlinear Systems (nth-FASAM-N): II. Illustrative Example
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2024年第1期43-95,共54页
This work highlights the unparalleled efficiency of the “n<sup>th</sup>-Order Function/ Feature Adjoint Sensitivity Analysis Methodology for Nonlinear Systems” (n<sup>th</sup>-FASAM-N) by con... This work highlights the unparalleled efficiency of the “n<sup>th</sup>-Order Function/ Feature Adjoint Sensitivity Analysis Methodology for Nonlinear Systems” (n<sup>th</sup>-FASAM-N) by considering the well-known Nordheim-Fuchs reactor dynamics/safety model. This model describes a short-time self-limiting power excursion in a nuclear reactor system having a negative temperature coefficient in which a large amount of reactivity is suddenly inserted, either intentionally or by accident. This nonlinear paradigm model is sufficiently complex to model realistically self-limiting power excursions for short times yet admits closed-form exact expressions for the time-dependent neutron flux, temperature distribution and energy released during the transient power burst. The n<sup>th</sup>-FASAM-N methodology is compared to the extant “n<sup>th</sup>-Order Comprehensive Adjoint Sensitivity Analysis Methodology for Nonlinear Systems” (n<sup>th</sup>-CASAM-N) showing that: (i) the 1<sup>st</sup>-FASAM-N and the 1<sup>st</sup>-CASAM-N methodologies are equally efficient for computing the first-order sensitivities;each methodology requires a single large-scale computation for solving the “First-Level Adjoint Sensitivity System” (1<sup>st</sup>-LASS);(ii) the 2<sup>nd</sup>-FASAM-N methodology is considerably more efficient than the 2<sup>nd</sup>-CASAM-N methodology for computing the second-order sensitivities since the number of feature-functions is much smaller than the number of primary parameters;specifically for the Nordheim-Fuchs model, the 2<sup>nd</sup>-FASAM-N methodology requires 2 large-scale computations to obtain all of the exact expressions of the 28 distinct second-order response sensitivities with respect to the model parameters while the 2<sup>nd</sup>-CASAM-N methodology requires 7 large-scale computations for obtaining these 28 second-order sensitivities;(iii) the 3<sup>rd</sup>-FASAM-N methodology is even more efficient than the 3<sup>rd</sup>-CASAM-N methodology: only 2 large-scale computations are needed to obtain the exact expressions of the 84 distinct third-order response sensitivities with respect to the Nordheim-Fuchs model’s parameters when applying the 3<sup>rd</sup>-FASAM-N methodology, while the application of the 3<sup>rd</sup>-CASAM-N methodology requires at least 22 large-scale computations for computing the same 84 distinct third-order sensitivities. Together, the n<sup>th</sup>-FASAM-N and the n<sup>th</sup>-CASAM-N methodologies are the most practical methodologies for computing response sensitivities of any order comprehensively and accurately, overcoming the curse of dimensionality in sensitivity analysis. 展开更多
关键词 Nordheim-Fuchs Reactor Safety Model Feature functions of Model parameters High-Order Response Sensitivities to parameters Adjoint Sensitivity Systems
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融合结构重参数化变换的气体泄漏红外检测
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作者 庄宏 张印辉 +1 位作者 何自芬 曹辉柱 《光子学报》 EI CAS CSCD 北大核心 2024年第1期187-201,共15页
针对常规工业气体泄漏检测装置需泄漏扩散到一定范围并与传感器接触时才能响应的不足,提出一种融合结构重参数化变换的红外非接触式检测网络模型GRNet。GRNet模型采用Mosaic-Gamma变换的预处理方法增加泄漏样本数量并提高图像对比度以... 针对常规工业气体泄漏检测装置需泄漏扩散到一定范围并与传感器接触时才能响应的不足,提出一种融合结构重参数化变换的红外非接触式检测网络模型GRNet。GRNet模型采用Mosaic-Gamma变换的预处理方法增加泄漏样本数量并提高图像对比度以增强模型的鲁棒性;通过K-means聚类分析出适用于气体泄漏红外检测的候选框以预置模型参数;优化定位损失函数以提高模型对泄漏区域的定位准确性;采用改进后的轻量化网络RepVGG模块重构特征提取网络增强模型的特征提取能力,以实现轻量化并提高检测精度。实验结果表明,GRNet模型对氨气泄漏的平均检测精度达到94.90%,单张图像平均检测时间达到3.40 ms。采用伪色彩映射实现泄漏浓度的视觉感知效果,采用PyQt5将GRNet模型进行封装实现气体泄漏红外检测系统界面的可视化并在Jetson Nano B01嵌入式实验平台部署该模型,验证了实际工程应用的可行性和有效性,为开发气体泄漏非接触探测装置以保障涉气企业的安全生产和稳定运行提供一种有效的检测算法。 展开更多
关键词 目标检测 气体泄漏检测 定位损失函数 图像预处理 聚类分析 结构重参数化
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复杂场景散射特性的参数化仿真模型
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作者 张尊 牟媛 +1 位作者 贺新毅 曾砾堂 《制导与引信》 2024年第1期43-52,共10页
针对复杂场景电磁散射特性的实时仿真需求,提出了一种基于散射中心的散射特性参数化仿真模型。首先基于数字高程数据,利用蒙特卡罗法补充粗糙度信息,构建复杂地形网格模型;再利用双向反射分布函数修正的属性散射中心(bidirectional refl... 针对复杂场景电磁散射特性的实时仿真需求,提出了一种基于散射中心的散射特性参数化仿真模型。首先基于数字高程数据,利用蒙特卡罗法补充粗糙度信息,构建复杂地形网格模型;再利用双向反射分布函数修正的属性散射中心(bidirectional reflection distribution function modified attribute scattering center,BRDF-ASC)模型建立参数化仿真模型。数值实验结果表明:所提算法仿真的典型山峰和沙丘地形的雷达散射截面积(radar cross section,RCS)与物理光学(physical optics,PO)法仿真的RCS的均值误差低于3.6 dBsm;与大型海港的实测合成孔径雷达(synthetic aperture radar,SAR)图像进行对比,其参数化散射模型仿真SAR图像的变更检出率为0.1097,验证了所提算法的可行性。 展开更多
关键词 参数化模型 复杂场景 双向反射分布函数 合成孔径雷达成像
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GENERALIZED RAY APPROXIMATE METHOD TO INVERSE MEDIUM PARAMETERS
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作者 Niu, YQ Du, DS +1 位作者 Ma, XG Huang, WH 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第1期59-65,共7页
In this paper, the inverse problem of the medium parameters in an inhomogeneous medium is studied and a generalized ray approximate form of the total wave field is described. First, the acoustic wave equation derived ... In this paper, the inverse problem of the medium parameters in an inhomogeneous medium is studied and a generalized ray approximate form of the total wave field is described. First, the acoustic wave equation derived from the elastic wave equation is studied, the referential variables and perturbational variables are introduced, and the integral equation of the medium perturbational parameters is obtained. Then from the point of view of the local principles of the wave function in an inhomogeneous medium, a generalized ray approximate form of the total wave field in an inhomogeneous medium is described, and attention is focused on the Fredholm integral equation of the first kind. Finally, the medium parameters in half-plane are inversed. Numerical examples show when the perturbations of the medium parameters are about 0.5, this method can effectively inverse its variation. Apparently, this method is better than the conventional Born weak scattering approximation. 展开更多
关键词 integral equation generalized ray approximation medium parameters function integral transform
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THE INTEGRAL AS A FUNCTlON OF THE UPPER LIMIT AND DEPENDING ON A PARAMETER TO SOLVE DRAWING THROUGH IDLING ROLLS
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作者 赵德文 赵志业 张强 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期93-100,共8页
The relocity and sirain-rate .field which are different from Avilzur's have beenestablished in Caitesian coordinates. Using the integral as a function of the upper limitand integration depending on a parameler, an... The relocity and sirain-rate .field which are different from Avilzur's have beenestablished in Caitesian coordinates. Using the integral as a function of the upper limitand integration depending on a parameler, an analylical upper-bound solution todrawing stress through idling rolls has been obtained in this paper. 展开更多
关键词 drawing through idling rolls integral as a function of theupper limit. integration depending on a parameter analyticalsolution
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FBFN-based adaptive repetitive control of nonlinearly parameterized systems
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作者 Wenli Sun Hong Cai Fu Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期1003-1010,共8页
An adaptive repetitive control scheme is presented for a class of nonlinearly parameterized systems based on the fuzzy basis function network (FBFN). The parameters of the fuzzy rules are tuned with adaptive schemes... An adaptive repetitive control scheme is presented for a class of nonlinearly parameterized systems based on the fuzzy basis function network (FBFN). The parameters of the fuzzy rules are tuned with adaptive schemes. To attenuate chattering effectively, the discontinuous control term is approximated by an adaptive PI control structure. The bound of the discontinuous control term is assumed to be unknown and estimated by an adaptive mechanism. Based on the Lyapunov stability theory, an adaptive repetitive control law is proposed to guarantee the closed-loop stability and the tracking performance. By means of FBFNs, which avoid the nonlinear parameterization from entering into the adaptive repetitive control, the controller singularity problem is solved. The proposed approach does not require an exact structure of the system dynamics, and the proposed controller is utilized to control a model of permanent-magnet linear synchronous motor subject to significant disturbances and parameter uncertainties. The simulation results demonstrate the effectiveness of the proposed method. 展开更多
关键词 adaptive control nonlinear parameterization repetitive control fuzzy basis function network (FBFN) permanentmagnet linear synchronous motor (PMLSM)
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基于CST参数化的导弹三维几何建模方法
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作者 关通 陈鹏云 +2 位作者 沈剑 张国兵 马英琪 《航空兵器》 CSCD 北大核心 2023年第1期59-63,共5页
针对建模效率低、成本高的问题,本文在二维CST参数化方法的基础上,引入纵向轮廓描述函数,将原二维建模向三维建模扩展,建立能够准确描述导弹三维形状特征的解析函数。在此基础上,通过在VB环境中对CATIA进行二次开发,使其能够在CATIA中... 针对建模效率低、成本高的问题,本文在二维CST参数化方法的基础上,引入纵向轮廓描述函数,将原二维建模向三维建模扩展,建立能够准确描述导弹三维形状特征的解析函数。在此基础上,通过在VB环境中对CATIA进行二次开发,使其能够在CATIA中进行自动生成、修补和更新。几何模型可以被导出和保存,并作为多学科设计与分析的基础。结果表明,本文提出的三维CST建模技术可以满足复杂几何建模的要求,有效简化了导弹参数化过程。 展开更多
关键词 CST参数化 CATIA二次开发 类别函数 形状函数 参数化建模 导弹
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基于径向基函数的残缺点云数据修复 被引量:31
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作者 陈飞舟 陈志杨 +2 位作者 丁展 叶修梓 张三元 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2006年第9期1414-1419,共6页
提出一种具有较强鲁棒性的残缺点云数据修复算法,借助kD tree寻找点云的缺陷边界,确定点云的缺陷区域;然后利用二次曲面的特性参数化边界点列;最后,通过径向基函数表示的插值曲面计算位于残缺区域内部的数据点,实现残缺点云数据的修复.
关键词 点云 孔洞修补 径向基函数 插值曲面 参数化
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一种海冰热力过程参数化方案 被引量:5
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作者 王可光 白珊 吴辉碇 《海洋预报》 北大核心 1999年第3期104-113,共10页
由于海冰热力过程太复杂,难于精确计算冰面和水面热量收支方程中的每一项,并且净热量收支比每项小得多,因此难以确定海冰热力一动力模式中的净热通量。本文根据渤海的水文气象观测,详细分析了太阳短波辐射、长波辐射、云量、感热和... 由于海冰热力过程太复杂,难于精确计算冰面和水面热量收支方程中的每一项,并且净热量收支比每项小得多,因此难以确定海冰热力一动力模式中的净热通量。本文根据渤海的水文气象观测,详细分析了太阳短波辐射、长波辐射、云量、感热和潜热等对海冰热力增长函数的贡献,给出了一种海冰热力过程的参数化方案。并选取2个典型的个例进行了对比研究。模拟结果表明,该参数化方案能较好地模拟渤海海冰的热力过程。 展开更多
关键词 海冰热力过程 热力增长函数 参数化 海冰
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通用测试平台的讨论 被引量:6
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作者 程作仁 李丽 +1 位作者 高明伦 张多利 《微电子学与计算机》 CSCD 北大核心 2001年第5期4-7,11,共5页
文章着重从结构、管理、工具支持、测试人员的使用及平台的安全性等几个方面对如何建立可升级数化的通用测试平台提出一种解决方案,并努力使之具有普适性,以期指导更多的工程实践。
关键词 通用测试平台 参数化 兼容性 数字电路
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基于新型神经网络PID控制器的温室温度控制技术 被引量:7
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作者 付丽辉 尹文庆 《计算机测量与控制》 CSCD 北大核心 2012年第9期2423-2425,2428,共4页
针对温室温度控制系统所存在的大惯性、非线性等问题,对基于重新参数化的B样条神经网络以及考虑到早熟现象的改进粒子群算法的B-BP-PSO-PID控制器进行研究;提出由PSO寻优找到最适合的β因子,得到适合权值搜索的最佳B样条基函数;提出由... 针对温室温度控制系统所存在的大惯性、非线性等问题,对基于重新参数化的B样条神经网络以及考虑到早熟现象的改进粒子群算法的B-BP-PSO-PID控制器进行研究;提出由PSO寻优找到最适合的β因子,得到适合权值搜索的最佳B样条基函数;提出由考虑早熟处理的改进粒子群算法取代传统BP后向传播算法来作为学习算法,有效克服传统算法易于陷入局部最优的缺点;仿真中以某温室20个不同时间的温度数据作为测试样本,结果表明,新型控制器的平均超调量为9.9%,平均响应时间为8.7s,可以实现对温室温度的最优化控制。 展开更多
关键词 温室 温度控制 B样条函数 重新参数化 粒子群算法 PID
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INTERPOLATION OF LORENTZ-ORLICZ MARTINGALE SPACES 被引量:3
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作者 张传洲 潘誉 张学英 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1467-1474,共8页
In this paper, we apply function parameters to real interpolation of Lorentz- Orlicz martingale spaces. Some new interpolation theorems are formulated which generalize some known results in Lorentz spaces An introduce... In this paper, we apply function parameters to real interpolation of Lorentz- Orlicz martingale spaces. Some new interpolation theorems are formulated which generalize some known results in Lorentz spaces An introduced by Sharpley. 展开更多
关键词 MARTINGALE Lorentz-Orlicz space INTERPOLATION function parameter
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机械CAD软件参数化绘图程序的专用函数编制 被引量:5
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作者 徐格宁 田仙云 《现代制造工程》 CSCD 2006年第10期39-41,共3页
针对企业产品特征,开发专用的机械CAD系统,以实现基于设计数据驱动的参数化绘图,能够提高设计效率。以W indows为操作系统,VC++6.0为开发平台,AutoCAD为图形支撑软件,SCR命令文件为参数化绘图接口,基于桥式起重机参数绘图软件开发的高... 针对企业产品特征,开发专用的机械CAD系统,以实现基于设计数据驱动的参数化绘图,能够提高设计效率。以W indows为操作系统,VC++6.0为开发平台,AutoCAD为图形支撑软件,SCR命令文件为参数化绘图接口,基于桥式起重机参数绘图软件开发的高效率和模块化需求,对软件中大量使用的特征图形、标准符号进行专用函数的编制开发,以达到减少参数化绘图软件编程工作量的目的。 展开更多
关键词 专用函数 AUTOCAD 参数化绘图 命令文件
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计算非均匀地表通量的一种简化PDF及其应用 被引量:7
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作者 刘晶淼 王纪军 丁裕国 《高原气象》 CSCD 北大核心 2002年第6期583-590,共8页
提出描述地表非均匀特性的简化概率密度函数 (PDF) ,它可代替各种具体的PDF用于求解次网格尺度平均通量而不影响其精度 ,这种简化PDF可直接加入陆面过程模式方程组中进行陆 -气通量交换的数值试验。它对非均匀地表陆面过程参数化具有一... 提出描述地表非均匀特性的简化概率密度函数 (PDF) ,它可代替各种具体的PDF用于求解次网格尺度平均通量而不影响其精度 ,这种简化PDF可直接加入陆面过程模式方程组中进行陆 -气通量交换的数值试验。它对非均匀地表陆面过程参数化具有一定的普适性。本文仅讨论了对称分布的简化计算 (非对称分布另文讨论 ) ,列举了非均匀分布的观测事实 ,并以地表净红外辐射通量计算为例 ,详细验证了应用这种简化PDF的可行性和可靠性。 展开更多
关键词 陆面过程 非均匀地表 概率密度函数 空间分布 参数化 地表净红外辐射通量
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基于Hicks-Henne型函数的翼型参数化设计以及收敛特性研究 被引量:12
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作者 刘丽娜 吴国新 《科学技术与工程》 北大核心 2014年第30期151-155,共5页
翼型参数化是风力机翼型优化设计中的重要环节。针对风力机翼型参数化中建立统一数学模型问题,研究HicksHenne型函数法及其改进算法在风力机翼型参数化中的应用。通过对Hicks-Henne型函数各项系数进行控制,避免出现翼型交叉与不光顺现象... 翼型参数化是风力机翼型优化设计中的重要环节。针对风力机翼型参数化中建立统一数学模型问题,研究HicksHenne型函数法及其改进算法在风力机翼型参数化中的应用。通过对Hicks-Henne型函数各项系数进行控制,避免出现翼型交叉与不光顺现象,保证了翼型整体形状的平滑。通过对关键点和设计变量的控制,研究设计空间覆盖性和设计变量对翼型的影响。分析了Hicks-Henne型函数法对翼型后缘设计的缺陷,并提出改进的Hicks-Henne算法改善尾缘夹角。Hicks-Henne型函数及其改进算法扩展了风力机翼型参数化表达方法,具有一定的工程实用价值。 展开更多
关键词 风力机Hicks-Henne型函数 翼型参数化
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肌理韵律的参数化实现 被引量:3
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作者 殷晓晨 刘勇 +1 位作者 王娜 吴世蔚 《包装工程》 CAS 北大核心 2022年第6期176-185,共10页
目的以肌理设计中蕴含的韵律为研究对象,通过参数化的设计方法,将肌理设计中的韵律构成由定性的表现转化为定量的设计,借助计算机强大的运算能力可以有效提升肌理设计的智能化、系统性与适应性。方法通过系统分析肌理设计的韵律法则,建... 目的以肌理设计中蕴含的韵律为研究对象,通过参数化的设计方法,将肌理设计中的韵律构成由定性的表现转化为定量的设计,借助计算机强大的运算能力可以有效提升肌理设计的智能化、系统性与适应性。方法通过系统分析肌理设计的韵律法则,建立基于肌理韵律的数学函数模型,并将其作为肌理参数化设计的基本参数输入参数化设计系统进行编码识别,在此基础上构建参数化设计框架,实现基于韵律法则的肌理参数化设计。结论在参数化设计框架基础上构建肌理参数化设计平台,借助可自定义的肌理韵律的函数模型,可以丰富肌理韵律的参数化生成形式,为肌理韵律的设计提供科学的方法指导。参数化的实时交互技术可以快速生成大量肌理设计方案,有助于提高设计效率,方便生成优化的肌理设计方案。 展开更多
关键词 肌理设计 肌理韵律 参数化 函数模型
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参数化的多次散射激光雷达方程和它的反演理论 Ⅰ:方程 被引量:4
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作者 邱金桓 H.Quenzel M.Wiegner 《大气科学》 CSCD 北大核心 1992年第5期601-611,共11页
本文提出了一个参数化的多次散射激光雷达方程,该方程基于本文引出的四个因子,即几何消光因子、消光分布因子、前向散射因子和后向散射因子.前两个因子表征多次散射成分对大气消光系数分布、激光的发散角和接收视场角以及接收孔径的依... 本文提出了一个参数化的多次散射激光雷达方程,该方程基于本文引出的四个因子,即几何消光因子、消光分布因子、前向散射因子和后向散射因子.前两个因子表征多次散射成分对大气消光系数分布、激光的发散角和接收视场角以及接收孔径的依赖关系,后两个因子表征多次散射成分对散射相函数的依赖关系.这个参数化多次散射雷达方程在241个数值试验中得以检验,这些试验包含很宽的大气条件和雷达几何参数,包括14个大气散射相函数,均匀和不均匀的大气消光系数分布,0.5至1之间变化的一次散射反照率,地基和空间站激光雷达两种情形.数值试验表明,在小于4的光学厚度内参数化的解和Monte-Carlo解之间的标准偏差小于27%,而本模式的计算时间比Monte-Carlo方法偏小4个数量级左右.本模式不仅适合于研究多次散射对激光回波信号和激光大气遥感的效应,而且对于考虑多次散射的激光大气探测而言,是一个合适的应用模式. 展开更多
关键词 多次散射 参数 大气 激光雷达
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