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	Localizability With Range-Difference Measurements: Numerical Computation and Error Bound Analysis 期刊论文 OAI收割 IEEE-ACM TRANSACTIONS ON NETWORKING, 2022, 页码: 14 作者: Zeng, Guangyang; Mu, Biqiang; Wei, Jieqiang; Wong, Wing Shing; Wu, Junfeng \| 收藏 \| 浏览/下载：44/0 \| 提交时间：2022/06/21 Location awareness Noise measurement Error analysis Pollution measurement Measurement uncertainty Coordinate measuring machines Closed-form solutions Localization time difference of arrival (TDOA) nonconvex optimization numerical computation Lagrange multiplier
	Ranging technology using signals of opportunity of non-cooperative communication satellites 期刊论文 OAI收割 JOURNAL OF NAVIGATION, 2021, 卷号: 74, 期号: 2, 页码: 488-500 作者: Gao, Yuanyuan; Hua, Yu \| 收藏 \| 浏览/下载：43/0 \| 提交时间：2021/11/29 navigation via signals of opportunity (NAVSOP) very long baseline interferometry (VLBI) passive radar detection time difference measurement
	Chromatic analysis of harmonic Fresnel lenses by FDTD and angular spectrum methods 期刊论文 OAI收割 Applied Optics, 2018, 卷号: 57, 期号: 19, 页码: 5281-5287 作者: Yang, Jianming; Twardowski, Patrice; Gerard, Philippe; Yu, Wenhui; Fontaine, Joel \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2019/09/17 Time domain analysis Angle measurement Diffraction efficiency Efficiency Finite difference time domain method Full width at half maximum Harmonic analysis Optical instrument lenses Refractive index Spectrum analysis
	AUTONOMOUS INTEGRATED NAVIGATION USING X-RAY PULSARS AND ASTEROIDS 会议论文 OAI收割 63rd International Astronautical Congress 2012, IAC 2012, Naples, Italy, 2012 Yang Chengwei; Gao Dong; Zheng Jianhua 收藏 \| 浏览/下载：39/0 \| 提交时间：2014/04/30 To improve the navigation performance of the spacecraft during interplanetary cruise a novel integrated navigation system is proposed. For X-ray pulsar navigation (XNAV) is a hot and prospective research subject and the optical navigation using asteroids is practical in space engineering we designed an autonomous navigation system using one X-ray detector and one navigation camera. The measurement models of the XNAV based on the time difference of arrival and the optical navigation based on the images of asteroids are presented. To enhance practicality the X-ray pulsars and asteroids are observed by turns. The batch least square filter used by Deep Space I is adopted to estimate the system state. The numerical simulation results show that the integrated navigation is feasible on the interplanetary cruise orbit. Moreover compared with the XNAV and the optical navigation the integrated navigation system can provide higher navigation performance.
	Mode analysis for in-plane emission microdisk resonator 期刊论文 OAI收割 2011 symposium on photonics and optoelectronics, sopo2011, 2011, 页码: 5780555 Guo, Chu-Cai; Huang, Yong-Zhen 收藏 \| 浏览/下载：25/0 \| 提交时间：2012/06/13 Finite difference time domain method Optoelectronic devices Photonics Q factor measurement Refractive index Waveguides
	The application study on building materials with computer color quantification system (EI CONFERENCE) 会议论文 OAI收割 ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Yu H.; Li Z.; Li Z. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 The first impression of any building to a person is its exterior and decoration therefore at the same time and therefore the quality of decoration project shows the more important position in building project. A lot of projects produce quality problem because of the material color difference how to grasp and control the color change of building materials the color difference problem laying stone materials is also studied in this paper which exists universally at the common project and carry out color quantification and the solution scheme has been given using this system. and is often found at the high-grade decoration it has the very important meaning. According to the color theory a computer vision system used in color quantification measurement is established the standard illuminant A is selected as the light source. In order to realize the standardization of color evaluation the mutual conversion between RGB and XYZ color space is studied which is realized by the BP network. According to the colorimetry theory the computer program is compiled in order to establish the software system and realize the color quantitative appraisement in whole color gamut. LCH model is used at quantifying the color of building materials and LaV model is used at comparing the color change. If the wooden floor is selected and laid improperly during family fitment it is easy to present "flower face". The color also arises greater discrepancy using the laths of same tree. We can give the laying scheme using the color quantification system
	Intelligent MRTD testing for thermal imaging system using ANN (EI CONFERENCE) 会议论文 OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China Sun J.; Ma D. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 The Minimum Resolvable Temperature Difference (MRTD) is the most widely accepted figure for describing the performance of a thermal imaging system. Many models have been proposed to predict it. The MRTD testing is a psychophysical task for which biases are unavoidable. It requires laboratory conditions such as normal air condition and a constant temperature. It also needs expensive measuring equipments and takes a considerable period of time. Especially when measuring imagers of the same type the test is time consuming. So an automated and intelligent measurement method should be discussed. This paper adopts the concept of automated MRTD testing using boundary contour system and fuzzy ARTMAP but uses different methods. It describes an Automated MRTD Testing procedure basing on Back-Propagation Network. Firstly we use frame grabber to capture the 4-bar target image data. Then according to image gray scale we segment the image to get 4-bar place and extract feature vector representing the image characteristic and human detection ability. These feature sets along with known target visibility are used to train the ANN (Artificial Neural Networks). Actually it is a nonlinear classification (of input dimensions) of the image series using ANN. Our task is to justify if image is resolvable or uncertainty. Then the trained ANN will emulate observer performance in determining MRTD. This method can reduce the uncertainties between observers and long time dependent factors by standardization. This paper will introduce the feature extraction algorithm demonstrate the feasibility of the whole process and give the accuracy of MRTD measurement.
	Study of micro-actuator with electrostatic actuating (EI CONFERENCE) 会议论文 OAI收割 ICO20: MEMS, MOEMS, and NEMS, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu C.-X.; Liu C.-X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 The micro-actuator with the torsion beam and the cantilever beam on silicon is designed and analyzed which is actuated by electrostatic force. Based on the torsion dynamics theory the technique and relative formula are presented for analyzing the actuating voltage and the switching time on which the effect of the air squeeze film damping is already considered. The optimized results of the structural parameters are compared between this technique and the finite element modeling (FEM). The optimized result of parameters is as: length width and thickness of the torsion beam are 700 12 and 10m length and width of the cantilever beam are 1900 and 1000m length and width of the balance beam are 100 and 1000m and distance of the upper and lower electrodes is 55m respectively. The actuating voltage is about 50 V and the switching time Toff and Ton are about 5 and 12 ms respectively. The computed results show that the air squeeze film damping is an important factor for the study of dynamic response on micro-actuator. Finally an optical technique is described for the measurement of the actuating voltage and switching time of the device and the difference between the experimental results and theoretical datum is discussed.