中国科学院机构知识库网格系统: 检索

System Signal-to-Noise Ratio Analysis of Hyperspectral Imaging Chain Model Based on Electron Multiplication 期刊论文 OAI收割
Guangxue Xuebao/Acta Optica Sinica, 2018, 卷号: 38, 期号: 11
作者: Yu, Da; Liu, Jinguo; He, Xin; He, Jiawei; Chen, Jiayu

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收藏 | 浏览/下载：22/0 | 提交时间：2019/09/17

Signal to noise ratio Atmospheric radiation Charge coupled devices Detectors Electrons Hyperspectral imaging Light transmission Optical systems Reflection Spectroscopic analysis Spectroscopy

Identifying Dynamic Functional Connectivity Biomarkers Using GIG-ICA: Application to Schizophrenia, Schizoaffective Disorder, and Psychotic Bipolar Disorder 期刊论文 OAI收割
Human Brain Mapping, 2017, 卷号: 38, 期号: 5, 页码: 2683-2708
作者: Du, Yuhui; Pearlson, Godfrey D.; Lin, Dongdong Sui, Jing(隋婧); Chen, Jiayu; Salman, Mustafa

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收藏 | 浏览/下载：45/0 | 提交时间：2018/03/09

Functional Magnetic Resonance Imaging Dynamic Functional Connectivity Independent Component Analysis Schizophrenia Schizoaffective Disorder Bipolar Disorder Default Mode Network Phenotypes B-snip Time-varying Connectivity Global Signal Regression State Brain Networks Resting-state Frontal-lobe Fmri Dsm-5 Anticorrelations

Relationships between B-mode ultrasound imaging signals and suspended sediment concentrations 期刊论文 OAI收割
MEASUREMENT, 2016, 卷号: 92, 页码: 34-41
作者: Song, Huan; Ma, Zhimin; Wang, Chuanying; Zou, Xianjian

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收藏 | 浏览/下载：29/0 | 提交时间：2018/06/05

B-mode ultrasound device Imaging signal analysis River model test Relationship research Suspended sediment concentration

Comparison of radiation temperature measurement precision between middlewave and longwave thermal-imaging systems (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者: Sun Z.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

A comparison study on temperature measurement precision between middlewave 3-5m and longwave 8-12m measuring thermal imaging systems has been conducted. The study was limited to systems working in indoor conditions and the target's temperature is in the range of 270K900K. First the Disturb Resisting Function (DRF) of infrared systems is deduced. On the base of DRF curve we find that the middlewave infrared system get the smaller influences under the same size disturb compared with the longwave system. A theory of the influence of target's physical characteristic and measurement conditions on the accuracy of temperature measurements has been developed. On the basis of the developed formulas an analysis of the influence of signal disturbances (because of incorrectly assumed emissivity limited transmittance of the atmosphere radiation reflected by the object and shift of optics radiation) on the accuracy of temperature measurement has been made. It has been found that the middlewave systems in typical temperature range offer generally better accuracy in temperature measurement than the longwave ones do. 2012 IEEE.

Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Zhang Z.-D.

收藏 | 浏览/下载：49/0 | 提交时间：2013/03/25

Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Parameters extraction of crop based on PolSAR data 会议论文 OAI收割
2nd International Conference on Image Analysis and Signal Processing, IASP'2010,, Xiamen, China, April 12, 2010 - April 14,2010
Cai, Aimin; Shao, Yun; Gong, Huaze

收藏 | 浏览/下载：14/0 | 提交时间：2014/12/07

Polarimeters Crops Eigenvalues and eigenfunctions Image analysis Imaging systems Parameter extraction Polarization Polarographic analysis Radar Scattering Signal processing Soil moisture Synthetic aperture radar

The research for EO imaging system simulation (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China
作者: Wang L.-J.; Zhang X.; Zhang X.; Zhang X.; Zhang J.-P.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

Electric-Optical (EO) imaging systems are modern systems especially the one consists of aspheric optics and image processing called wavefront coding system. The design concept of this kind system is totally different from the traditional image system. The trade-off between the complexity of the image deconvolution and the depth of focus extended should be considered. So we establish a simulation model consisting of optical optimization design system signal-to-noise ratio analysis and recovered image evaluation. The data can be exchanged among them. This simulation tools will be very useful in system design process.

Non-parameter correlation analysis in polarimetric signature and its application to change detection in polarimetric SAR 会议论文 OAI收割
2008 IEEE International Geoscience and Remote Sensing Symposium - Proceedings, Boston, MA, United states, July 6, 2008 - July 11,2008
Tian, Bangsen; Li, Zhen; Wang, Yongqian

收藏 | 浏览/下载：22/0 | 提交时间：2014/12/07

Statistics Asymptotic analysis Ellipsometry Imaging systems Polarimeters Polarization Polarographic analysis Probability density function Probability distributions Regression analysis Remote sensing Signal detection Statistical tests Synthetic aperture radar Synthetic apertures

Residual-scaled local standard deviations method for estimating noise in hyperspectral images 会议论文 OAI收割
MIPPR 2007: Multispectral Image Processing, Wuhan, China, November 15, 2007 - November 17,2007
Gao, Lianru; Zhang, Bing; Wen, Jianting; Ran, Qiong

收藏 | 浏览/下载：24/0 | 提交时间：2014/12/07

Spurious signal noise Image analysis Imaging systems Infrared imaging Linear regression

Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割
2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China
作者: Li J.; Liu J.; Liu J.; Liu J.; Li J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.