检索结果-南通市图书馆

同方期刊数据库

Prediction of the thermospheric and ionospheric responses to the 21 June 2020 annular solar eclipse

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2020年第3期4卷 231-237页

作者： Tong Dang JiuHou Lei WenBin Wang MaoDong Yan dexin ren FuQing Huang Chinese Academy of Sciences Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China High Altitude Observatory National Center for Atmospheric ResearchBoulderCOUSA

On 21 June 2020,an annular solar eclipse will traverse the low latitudes from Africa to Southeast *** highest latitude of the maximum eclipse obscuration is approximately 30°.This low-latitude solar eclipse provides a unique and unprecedented opportunity to explore the impact of the eclipse on the low-latitude ionosphere–thermosphere(I–T)system,especially in the equatorial ionization anomaly *** this study,we describe a quantitative prediction of the impact of this upcoming solar eclipse on the I–T system by using Thermosphere–Ionosphere–Electrodynamics General Circulation Model simulations.A prominent total electron content(TEC)enhancement of around 2 TEC units occurs in the equatorial ionization anomaly region even when this region is still in the shadow of the *** TEC enhancement lasts for nearly 4.5 hours,long after the solar eclipse has *** model control simulations indicate that the TEC increase is mainly caused by the eclipse-induced transequatorial plasma transport associated with northward neutral wind perturbations,which result from eclipse-induced pressure gradient *** results illustrate that the effect of the solar eclipse on the I–T system is not transient and linear but should be considered a dynamically and energetically coupled system.

关键词： solar eclipse ionosphere thermosphere coupling equatorial ionization anomaly model simulation

Vibration control on shells through theoretical and numerical analysis

在线全文

学校读者我要写书评

暂无评论

International English Education Research 2014年第6期 40-43页

作者： dexin ren Jie Hong Lulu Chen School of Energy and Power Engineering Beijing university of aeronautics and astronautics Beijing 10019 I China AVIC commercial aircraft engine Co. LTD. Shanghai 201108 China

A theoretical and numerical study has been performed on an air film dumper attached to a plate structure. Combined with the analysis by Fox and Whittorg a damping model of the air fiim damper has been developed. A complex stiffness was introduced to represent the air pressure in the damper cavity. The stain energy and dissipated energy were integrated from the real part and imaginary part of the complex stiffness to determine the stiffness and damping. The response of the plate with the air film damper was considered by treating the air film as multiple discrete damping-stiffness elements using ANSYS.

关键词： Air film damper Complex stiffness FE damping-sfiffiaess element

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

相干斑噪声抑制技术研究

仪器仪表学报 2006年第Z2期27卷 1413-1416页

作者：赵久奋任德新赵玖玲闫肃第二炮兵工程学院西安710025 国防科技大学长沙410073

本文研究了一种新的合成孔径雷达相干斑噪声抑制的算法。传统的噪声抑制和近年来的小波变换方法都有其不足之处。本文结合增强Lee算法中的思想与小波算法用于抑制SAR图像中相干斑噪声,能够获得良好的效果,通过对比试验,本文算法具有较... 详细信息

本文研究了一种新的合成孔径雷达相干斑噪声抑制的算法。传统的噪声抑制和近年来的小波变换方法都有其不足之处。本文结合增强Lee算法中的思想与小波算法用于抑制SAR图像中相干斑噪声,能够获得良好的效果,通过对比试验,本文算法具有较好的相干斑噪声抑制能力和边缘保持能力。

关键词：合成孔径雷达斑点噪声小波分析图像

在线全文

学校读者我要写书评

暂无评论

基于SAGA及多尺度图像的配准技术研究

仪器仪表学报 2006年第Z3期27卷 2203-2205,2258页

作者：任德新赵久奋赵玖玲闫肃国防科技大学长沙410073 第二炮兵工程学院西安710025

图像配准是图像融合、目标检测识别和计算机视觉技术中重要的步骤和环节,用于消除来自不同传感器的图像中目标的差异。本文在研究基于最大互信息算法的基础上,提出了一种基于遗传算法和模拟退火算法的多尺度图像配准技术,仿真试验表明... 详细信息

图像配准是图像融合、目标检测识别和计算机视觉技术中重要的步骤和环节,用于消除来自不同传感器的图像中目标的差异。本文在研究基于最大互信息算法的基础上,提出了一种基于遗传算法和模拟退火算法的多尺度图像配准技术,仿真试验表明此算法准确有效。

关键词：图像配准模拟退火算法遗传算法多尺度分析

在线全文

学校读者我要写书评

暂无评论

经济增长与通货紧缩

生产力研究 2007年第2期 11-13,20页

作者：陆凯旋任德新南京审计学院江苏南京210029

人们将经济快速增长与物价持续下跌并存的特殊经济现象称为经济缩长。文章利用AD-AS模型从理论上阐述了这种现象的发生机理,指出这是由于AD、AS曲线均快速向右移动,但AS移动更快造成的,并通过实证数据证实我国1997年～2002年的经济缩长... 详细信息

人们将经济快速增长与物价持续下跌并存的特殊经济现象称为经济缩长。文章利用AD-AS模型从理论上阐述了这种现象的发生机理,指出这是由于AD、AS曲线均快速向右移动,但AS移动更快造成的,并通过实证数据证实我国1997年～2002年的经济缩长正是这样发生的。文章还指出经济缩长的危害并不在于物价下跌本身,而在于实际经济增长率低于潜在经济增长率,治理和防范经济缩长需要同时增加总需求和总供给。

关键词：经济缩长 AD-AS模型实证分析治理与防范

在线全文

学校读者我要写书评

暂无评论

日本八十年代股市泡沫的破灭及对我们的启示

南京航空航天大学学报（社会科学版） 2002年第1期4卷 29-32页

作者：任德新南京审计学院法学系江苏南京210029

企业热衷投机、机构炒作成风、股票价格高企是二十世纪八十年代末日本股市泡沫破灭之前的特征。在一个时期 ,我国股市也有类似的特征现象。加快发展金融市场步伐 ,实行积极监管 ,形成外部监督机制 ,完善上市公司法人治理结构 ,规范、培... 详细信息

企业热衷投机、机构炒作成风、股票价格高企是二十世纪八十年代末日本股市泡沫破灭之前的特征。在一个时期 ,我国股市也有类似的特征现象。加快发展金融市场步伐 ,实行积极监管 ,形成外部监督机制 ,完善上市公司法人治理结构 ,规范、培育和发展机构投资队伍 ,对抑制股市泡沫。

关键词：股市泡沫经济监管

A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett’s two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

物理实验教学中DISLab与传统实验器材的创新融合应用

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

物理教学 2023年第10期45卷 26-28页

作者：崔玉林任德鑫甘肃省榆中县第一中学甘肃730100 甘肃省榆中县恩玲中学甘肃730100

将传感器与传统实验“瓶吞鸡蛋”创新融合应用,依据数字化实验系统的数据分析结果,得出瓶内气体体积与压强变化之间的定量关系,进而科学严谨地验证玻意耳定律。

关键词：数字化实验系统传统实验玻意耳定律