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	A robust and powerful two-step testing procedure for local ancestry adjusted allelic association analysis in admixed populations 期刊论文 OAI收割 GENETIC EPIDEMIOLOGY, 2018, 卷号: 42, 期号: 3, 页码: 288-302 作者: Duan, Qing; Xu, Zheng; Raffield, Laura M.; Chang, Suhua; Wu, Di \| 收藏 \| 浏览/下载：64/0 \| 提交时间：2018/05/28 Admixed Populations Association Analysis Effect Heterogeneity Genome-wide Association Studies Gwas Local Ancestry Population Stratification Testing Procedure
	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：25/0 \| 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.
	Recent progress on asphere manufacturing and testing at CIOM (EI CONFERENCE) 会议论文 OAI收割 Advanced Optical Manufacturing and Testing Technology 2000, November 1, 2000 - November 3, 2000, Chengdu, China 作者: Zhang X.; Yu J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 The manufacturing procedure of a 500 mm in diameter f/2 hyperbolic primary mirror based on Computer-Controlled Polishing is introduced in detail. The mirror was finally polished to the shape accuracy of 13 nm rms and the surface roughness of 2 nm Ra. Testing methods and data analysis for different stages ranging from grinding to polishing are discussed. Some critical factors affecting the efficiency and accuracy of the grinding/polishing procedure are summarized. In addition the preliminary work to make large off-axis asphere mirrors is presented. The difficulties in polishing and testing for both circular aperture and rectangular aperture mirrors are previewed and a possible solution is given. To control the geometrical parameters such as radius of curvature and conic constant a new profiler has been built and it has proven very useful to improve the grinding efficiency. Finally the manufacturing of small aspheres using deterministic grinding tool is also introduced. The fine grinding procedure of LOH's asphere grinding machine is presented.