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优化光学亚像素定位精度极限——揭示小PSF的像素相位效应 Article
战海洋, 邢飞, 宝竞宇, 孙婷, 陈真真, 尤政, 袁利
《工程(英文)》 2023年 第27卷 第8期 页码 140-149 doi: 10.1016/j.eng.2023.03.009
Subpixel localization techniques for estimating the positions of point-like images captured by pixelated image sensors have been widely used in diverse optical measurement fields. With unavoidable imaging noise, there is a precision limit when estimating the target positions on image sensors, which depends on the detected photon count, noise, point spread function (PSF) radius, and PSF’s intra-pixel position. Previous studies have clearly reported the effects of the first three parameters on the precision limit but have neglected the intra-pixel position information. Here, we develop a localization precision limit analysis framework for revealing the effect of the intra-pixel position of small PSFs. To accurately estimate the precision limit in practical applications, we provide effective PSF (ePSF) modeling approaches and apply the Cramér-Rao lower bound. Based on the characteristics of small PSFs, we first derive simplified equations for finding the best precision limit and the best intra-pixel region for an arbitrary small PSF; we then verify these equations on real PSFs. Next, we use the typical Gaussian PSF to perform a further analysis and find that the final optimum of the precision limit is achieved at the pixel boundaries when the Gaussian radius is as small as possible, indicating that the optimum is ultimately limited by light diffraction. Finally, we apply the maximum likelihood method. Its combination with ePSF modeling allows us to successfully reach the precision limit in experiments, making the above theoretical analysis effective. This work provides a new perspective on combining image sensor position control with PSF engineering to make full use of information theory, thereby paving the way for thoroughly understanding and achieving the final optimum of the precision limit in optical localization.
关键词: Optical measurement Subpixel localization Precision limit optimization Small point spread functions Centroiding Star sensors
Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages
CHEN Xuedong, LI Zhixin
《机械工程前沿(英文)》 2008年 第3卷 第4期 页码 400-407 doi: 10.1007/s11465-008-0060-z
关键词: manufacture different interaction air-bearings response amplitude
Precision glass molding: Toward an optimal fabrication of optical lenses
Liangchi ZHANG,Weidong LIU
《机械工程前沿(英文)》 2017年 第12卷 第1期 页码 3-17 doi: 10.1007/s11465-017-0408-3
It is costly and time consuming to use machining processes, such as grinding, polishing and lapping, to produce optical glass lenses with complex features. Precision glass molding (PGM) has thus been developed to realize an efficient manufacture of such optical components in a single step. However, PGM faces various technical challenges. For example, a PGM process must be carried out within the super-cooled region of optical glass above its glass transition temperature, in which the material has an unstable non-equilibrium structure. Within a narrow window of allowable temperature variation, the glass viscosity can change from 105 to 1012 Pa·s due to the kinetic fragility of the super-cooled liquid. This makes a PGM process sensitive to its molding temperature. In addition, because of the structural relaxation in this temperature window, the atomic structure that governs the material properties is strongly dependent on time and thermal history. Such complexity often leads to residual stresses and shape distortion in a lens molded, causing unexpected changes in density and refractive index. This review will discuss some of the central issues in PGM processes and provide a method based on a manufacturing chain consideration from mold material selection, property and deformation characterization of optical glass to process optimization. The realization of such optimization is a necessary step for the Industry 4.0 of PGM.
关键词: precision glass molding optical lens constitutive modeling optimization manufacturing chain Industry 4.0
Foundations bearing capacity subjected to seepage by the kinematic approach of the limit analysis
Mehdi VEISKARAMI, Ghasem HABIBAGAHI
《结构与土木工程前沿(英文)》 2013年 第7卷 第4期 页码 446-455 doi: 10.1007/s11709-013-0227-5
关键词: foundation bearing capacity limit analysis numerical computation plasticity seepage
LIU Xiaojia, NING Fangfei
《能源前沿(英文)》 2008年 第2卷 第4期 页码 541-549 doi: 10.1007/s11708-008-0077-3
关键词: definition objective distribution fitting precision combination numerical aerodynamic
3D fracture modelling and limit state analysis of prestressed composite concrete pipes
Pengfei HE, Yang SHEN, Yun GU, Pangyong SHEN
《结构与土木工程前沿(英文)》 2019年 第13卷 第1期 页码 165-175 doi: 10.1007/s11709-018-0484-4
关键词: cylindrical concrete structures limit state analysis 3D fracture modelling prestressed composite pipes reinforced concrete three-point bending test
Modeling limit force capacities of high force to volume lead extrusion dampers
《结构与土木工程前沿(英文)》 2021年 第15卷 第3期 页码 609-622 doi: 10.1007/s11709-021-0724-x
关键词: extrusion lead dampers upper and lower bound analytical modelling limit force
ZHANG Kangkang, GU Enhua, LU Junjie
《医学前沿(英文)》 2008年 第2卷 第3期 页码 295-297 doi: 10.1007/s11684-008-0056-4
高建民,史晓军,许艾明,赵博选
《中国工程科学》 2013年 第15卷 第1期 页码 28-33
随着机床高速高精度的技术发展,热问题已成为影响机床特性的重要因素。从提高机床的固有热性能出发,系统介绍了机床热特性分析、热结构优化及其冷却技术的理论和方法,以及国内外研究现状,并探讨了机床“热设计”理论与技术的最新进展和未来研究重点及趋势。
Do not let precision medicine be kidnapped
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《医学前沿(英文)》 2015年 第9卷 第4期 页码 512-513 doi: 10.1007/s11684-015-0425-8
Obama’s precision medicine initiative made the medical community boil over after the initiative’s release. Precision medicine has been advocated by the majority of scientists and doctors. However, some experts have questioned this concept. This article does not oppose precision medicine. However, the incentive of vigorously promoting precision medicine at present is a concern.
A toughness based deformation limit for X- and K-joints under brace axial tension
Bo GU,Xudong QIAN,Aziz AHMED
《结构与土木工程前沿(英文)》 2016年 第10卷 第3期 页码 345-362 doi: 10.1007/s11709-016-0333-2
关键词: circular hollow section (CHS) tubular joint fracture failure deformation limit J-integral
Stability analysis of layered slopes in unsaturated soils
Guangyu DAI; Fei ZHANG; Yuke WANG
《结构与土木工程前沿(英文)》 2022年 第16卷 第3期 页码 378-387 doi: 10.1007/s11709-022-0808-2
关键词: slope stability suction stress unsaturated soil layered slope limit equilibrium
Review on the progress of ultra-precision machining technologies
Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG
《机械工程前沿(英文)》 2017年 第12卷 第2期 页码 158-180 doi: 10.1007/s11465-017-0455-9
Ultra-precision machining technologies are the essential methods, to obtain the highest form accuracy and surface quality. As more research findings are published, such technologies now involve complicated systems engineering and been widely used in the production of components in various aerospace, national defense, optics, mechanics, electronics, and other high-tech applications. The conception, applications and history of ultra-precision machining are introduced in this article, and the developments of ultra-precision machining technologies, especially ultra-precision grinding, ultra-precision cutting and polishing are also reviewed. The current state and problems of this field in China are analyzed. Finally, the development trends of this field and the coping strategies employed in China to keep up with the trends are discussed.
关键词: ultra-precision grinding ultra-precision cutting ultra-precision polishing research status in China development tendency
Adaptive selective ES-FEM limit analysis of cracked plane-strain structures
H. NGUYEN-XUAN,T. RABCZUK
《结构与土木工程前沿(英文)》 2015年 第9卷 第4期 页码 478-490 doi: 10.1007/s11709-015-0317-7
关键词: cracked structure limit analysis von Mises criterion edge-based strain smoothing second-order cone programming adaptive
Mantu MAJUMDER, Debarghya CHAKRABORTY
《结构与土木工程前沿(英文)》 2021年 第15卷 第2期 页码 537-551 doi: 10.1007/s11709-021-0708-x
关键词: bearing capacity uplift capacity under-reamed pile clay limit analysis
标题 作者 时间 类型 操作
Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages
CHEN Xuedong, LI Zhixin
期刊论文
Precision glass molding: Toward an optimal fabrication of optical lenses
Liangchi ZHANG,Weidong LIU
期刊论文
Foundations bearing capacity subjected to seepage by the kinematic approach of the limit analysis
Mehdi VEISKARAMI, Ghasem HABIBAGAHI
期刊论文
New response surface model and its applications in aerodynamic optimization of axial compressor blade
LIU Xiaojia, NING Fangfei
期刊论文
3D fracture modelling and limit state analysis of prestressed composite concrete pipes
Pengfei HE, Yang SHEN, Yun GU, Pangyong SHEN
期刊论文
Setting up a heart rate alarm limit to decrease oculocardiac reflex during strabismus surgery in children
ZHANG Kangkang, GU Enhua, LU Junjie
期刊论文
A toughness based deformation limit for X- and K-joints under brace axial tension
Bo GU,Xudong QIAN,Aziz AHMED
期刊论文
Review on the progress of ultra-precision machining technologies
Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG
期刊论文
Adaptive selective ES-FEM limit analysis of cracked plane-strain structures
H. NGUYEN-XUAN,T. RABCZUK
期刊论文