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	Frequency response-based decoupling tuning for feedforward compensation ADRC of distributed parameter systems 期刊论文 OAI收割 CONTROL ENGINEERING PRACTICE, 2022, 卷号: 126, 页码: 11 作者: Liu, Shaojie; Zhang, Yu-Long; Xue, Wenchao; Shi, Gengjin; Zhu, Min \| 收藏 \| 浏览/下载：34/0 \| 提交时间：2023/02/07 Distributed parameter systems Two-degree-of-freedom control Active disturbance rejection control Frequency response-based tuning Feedforward compensation Nyquist criterion Monte Carlo method Control of water channel Control of magnetic levitation
	The estimation method on diffusion spot energy concentration of the detection system 会议论文 OAI收割 8th international symposium on advanced optical manufacturing and testing technology (aomatt) - optical test, measurement technology, and equipment, suzhou, peoples r china, 2016-04-26 作者: Gao, Wei; Song, Zongxi; Liu, Feng; Dan, Lijun; Sun, Zhonghan 收藏 \| 浏览/下载：33/0 \| 提交时间：2016/12/02 Diffusion spot Nyquist frequency estimate concentration
	Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文 OAI收割 2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China 作者: Li Y.; He B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes quincunx sampling and four-point sampling a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679 respectively. MTFA in (0 0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications Switzerland.
	Space camera dynamic image quality measurement and evaluation (EI CONFERENCE) 会议论文 OAI收割 3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 By using analysis of the infinity image of the space camera we intend to obtain the curve of the dynamic modulation transfer function. We extract the pixel gray values at the image edge which distribute as a knife-edge function and make differential calculation and Fourier transformation of it and then we can obtain the dynamic MTF curve of the optical system. The value of the curve at the Nyquist frequency is the most important parameter that reflects the image quality. We add push-scanning imaging and environmental effects to the static MTF of space camera and compare the MTF value with the dynamic MTF at Nyquist frequency. The comparison result can help us verify the accuracy of the calculating results and the feasibility of our method. (2011) Trans Tech Publications.
	Modulation transfer function measurement technique for image sensor arrays (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Jiang H. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 A new technique is demonstrated for measurement of modulation transfer function (MTF) on image sensor arrays. Fourier analysis of a low frequency bar target pattern is used to extract MTF at odd harmonics of a target pattern frequency up to and beyond Nyquist. The technique is particularly useful for linear image arrays (either conventional linescan or time-delay-integration devices) where conventional slanted-edge technique is not always applicable. The technique is well suited to simple implementation and can provide live presentation of the MTF curve which helps to ensure optimal alignment conditions are achieved. Detailed analysis of the technique and demonstration of experimental results are presented. 2010 SPIE.
	Study on dynamic imaging on TDI CCD optical remote sensor of push-broom technology (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Liu L.; Ren J.-Y.; Liu L.; Gao M.-H. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 A set special detecting system is proposed based on TDICCD push-broom technology applying in dynamic imaging detecting experiment of space optics remote sensor. In the system In the course of detecting push-broom movement of the satellite is simulated through using double supporting U structure precision rotary platform with remote sensor by angular speed 0.555/s regard Nyquist frequency target as detecting aim within the range of 5 and control precision on steady speed achieves 0.3% in order to solve matching uncertainty between the CCD pixel and the vertical target strip image when the remote sensor does push-broom make matching simplify enhance the measurement result the accuracy. So the tolerance a/n arithmetic progression gap target strip is joined in each group of rectangular vertical group target strip. The remote sensor obtains in vertical the level and 45 the direction 0 fields of view 0.86 the field of view Nyquist frequency target strip image after detected a group target strip which can precision matching to TDICCD pixel at least can be obtained through analysis and dealing with 0.86 field of view's target strip image. The experiment not only verifies the detecting system's feasibility but simultaneously verifies whether to have the high quality dynamic imaging quality when TDICCD push-broom technology is adopted on the remote sensor developed. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Super-resolved imaging system with oversampling technology (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang X.; Wang L.-J.; Wang L.-J.; Zhang J.-P.; Liu Y. 收藏 \| 浏览/下载：62/0 \| 提交时间：2013/03/25 It has been a significant issue in the imaging filed to provide the highest possible resolution of an electro-optical imaging system(E-O imaging system). CCD arrays are inherently undersampled and spatial frequency above Nyquist frequency is distorted so as to create ambiguity and Moire patterns for targets imaged by E-O system.. As to this drawback a system-design project is introduced and discussed in the paper. It's well known that many image quality metrics are linked to MTF. However CCDs don't satisfy MTF condition namely the shift-invariant property so MTF synthesis can't appraise the whole system simply by the MTF product of the few sub-system ones in E-O imaging system. Then it is depicted how to solve this problem in the following. Finally the analyses and comparisons of the imaging performance parameters with and without super-resolved technologies are shown.
	Design of dual-FOV refractive/diffractive LWIR optical system (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Wang L.-J.; Zhang J.-P.; Wang L.-J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1 Second Others zoom ratio =1:4 binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate in order to balance 5th spherical aberration and dual field are 26.6 and 5.6respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320240 pixels and 45m pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First 5th coma aberration and 5th astigmatic aberration the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner high-order asphere surfaces with 2th order to 10 th order are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6 and the focal length is 152mm MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6 and the focal length is 38mm MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046 the coma aberration 0.055 and astigmatic aberration 0.034.