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	Bis-enzyme cascade CRISPR-Cas12a platform for miRNA detection 期刊论文 OAI收割 TALANTA, 2023, 卷号: 252, 页码: 7 作者: Guo, Zixuan; Tan, Xiao; Yuan, Haoyu; Zhang, Ling; Wu, Jiajia \| 收藏 \| 浏览/下载：55/0 \| 提交时间：2023/01/06 MicroRNA CRISPR-Cas12a T7 RNA polymerase All -in -one
	KLF4调控人体T细胞发育和T-ALL白血病机理研究学位论文 OAI收割广州生物院: 中国科学院研究生院, 2015 作者: 李巍 \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2018/12/24 KLF4 T细胞发育 T-ALL 白血病人源化小鼠
	Analysis of inertia dyadic uncertainty for small agile satellite with control moment gyros (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Mechatronics and Automation, ICMA 2010, August 4, 2010 - August 7, 2010, Xi'an, China 作者: Zhang L.; Zhang L.; Sun Z. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 With the increasing demands for the agility of the next earth imaging satellite control moment gyro (CMG) is considered to be the most suitable actuator because of its torque amplification capability. However a CMG system may introduce uncertainty of inertia dyadic to a satellite's attitude control system. The uncertainty is negligible for large space vehicles but it has not been tested whether it can be ignored for small agile satellites. How to model the CMG system inertia dyadic varying with gimbal angles and what influence it will put on the performance of attitude control system haven't been test accurately as well. All of them are dealt with mathematically and accurately in this paper. This paper firstly gives mathematic descriptions of the inertia dyadic of the 4-CMG pyramid configuration system varying with gimbal angles and then designs a variable structure control law for small agile satellite using CMGs. Finally numerical simulation suggests that the inertia dyadic variation of a 4-CMG pyramid configuration system is approximately centesimal of the total inertia dyadic of the satellite and that the designed variable structure control law is of good robust performance for an example of large-angle attitude maneuver despite of the variation of the inertia dyadic. 2010 IEEE.
	Adaptive resolution storage system based on LOG-POLAR transform for multi-target trackers (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer Application and System Modeling, ICCASM 2010, October 22, 2010 - October 24, 2010, Shanxi, Taiyuan, China 作者: Zhang Y. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 The main constrained problem of the video monitoring and storage system is the contradiction between large field of view and storage space limitations. Not all of the video information introduced by the image sensors need to be recorded especially for some tracking system which has appointed functions to track specifically kinds of targets. For instance the system not only works for single target if the monitor is appointed for human face tracking but also can work for multi-targets. High reconstruction resolution in the fovea region enables the successive application of recognition modules without sacrificing their performance the best system appears to be concentrating on human face only and all the others considered being background the low reconstruction resolution in the periphery helps to reduce the video data. 2010 IEEE. the background regions needn't to be recorded in detail. For this purpose this letter presents a real-time foveate storage system which efficiently represents the video image in log-polar coordinates with the foveate point centered on the target
	Transceiving protocol designc for a free space optical communication system (EI CONFERENCE) 会议论文 OAI收割 2008 International Conference on Optical Instruments and Technology: Optical Systems and Optoelectronic Instruments, November 16, 2008 - November 19, 2008, Beijing, China Hualong W.; Wanxin S.; Zhongbao X. 收藏 \| 浏览/下载：61/0 \| 提交时间：2013/03/25 A new transceiving protocol is demonstrated for a Free Space Optical (FSO) communication system and it's discussed in two parts: the transmitting protocol and the receiving protocol. During the discussion of these two parts the cooperation of them is also discussed. Different from wired communication an FSO system modulates the data on a narrow beam of laser transmitting through the free space or the atmosphere and the protocol presented in this paper is mainly optimized for terrestrial Free Space Optical links in which the signal channel of the system is mainly the atmosphere. Due to the complex composition and activity of the atmosphere this signal channel brings in great influence on the transmitting laser in it for example the absorption and scattering of the atmosphere molecules and aerosols the scintillation of received laser power caused by the turbulence of the atmosphere all of which results in a much higher Bit Error Rate (BER) of the communication system. Thus in designing a protocol for an FSO system more effort should be taken in the encoding of the data stream the synchronization of the data stream error checking and exception handling. The main function of the transmitting protocol includes interfacing the outer input data with a parallel port buffering the input data encoding the input data stream serializing the parallel data and output the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The main function of the receiving protocol includes filtering and synchronizing the input serial data stream paralleling the serial data stream decoding the input data error checking exception handling and interfacing the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces meaning that when interfacing the presented system to an outer system you don't have to consider what protocol the outer system transceiving data stream is under for example the TCP/IP protocol or anything else in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is working fine at a certain bit rate scale. 2009 SPIE.
	A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Sun Y.; Sun Y.; Wan Q.-H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid according to the difficulties of the detection of the magnetic fluid established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid which followed the movement of the magnetic fluid and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA whose width and depth were designed by the user as required. Then the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus whose transmission rate can reach 480Mb/s in theory. Finally the distribution of the laser speckle on the magnetic fluid was messy and random which carried certain information about the surface of the magnetic fluid based on the theories of the statistic correlation and the subdivision of images analysing and processing the laser speckle interferometric images indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court non-contact non-invasive high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.
	Data preprocessing of the exterior field of vision assembling photogrammetric camera (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Li J.; Li J.; Li J.; Liu J.; Liu J. 收藏 \| 浏览/下载：83/0 \| 提交时间：2013/03/25 Transmit array photogrammetric camera can obtain image which is high geometric fidelity and high photogrammetric quality. However the single chip array CCD image sensor camera can't meet the need of measuring precision and photogrammetric covering area. In order to obtain large numbers of information and extensive photogrammetric covering area we must increase field of vision angle and improve photogrammetric covering area. And all these objects can be realized by exterior field of vision assembling photogrammetric camera. Two side work must be done before images which obtained by exterior field of vision assembling photogrammetric camera be used in photogrammetry. First all assembling camera focal plane need be converted to a benchmark coordinate focal plane to realize camera digital assembling. Second images must be re-sampled and processing. Because of coordinate conversion two images from different assembling cameras can be established function relation which a pixel of image from a camera is corresponding to a pixel of another image from different camera. But through this conversion some pixels maybe extrusion together and other pixels separate on an image area. So interpolation direction finding(IDF) is used to obtain these pixels and realize image re-sampling. In this paper the structure of exterior field of vision assembling photogrammetric camera is analyzed and the coordinate conversion method of exterior field of vision assembling photogrammetric camera and image gray re-sampling method also can be discussed. All the works are based to data pretreatment of exterior vision assembling photogrammetric camera.
	Displacement estimation by the phase-shiftings of fourier transform in present white noise (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wu Y.-H. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Displacement estimation is a fundamental problem in Real-time video image processing. It can be typically approached by theories based on features in spatial domain. This paper presents an algorithm which improves the theory for estimating the moving object's displacement in spatial domain by its Fourier transform frequency spectrum. Because of the characters of Fourier transform the result is based on all the features in the image. Utilizing shift theorem of Fourier transform and auto-registration the algorithm employs the phase spectrum difference in polar coordinate of two frame images sequence with the moving target1 2. The method needn't transform frequency spectrum to spatial domain after calculation comparing with the traditional algorithm which has to search Direc peak and it reduces processing time. Since the technique proposed uses all the image information including all the white noise in the image especially and it's hard to overcome the aliasing from noises but the technique can be an effective way to analyze the result in little white noise by the different characters between high and low frequency bands. It can give the displacement of moving target within 1 pixel of accuracy. Experimental evidence of this performance is presented and the mathematical reasons behind these characteristics are explained in depth. It is proved that the algorithm is fast and simple and can be used in image tracking and video image processing.
	Aerial image blurring caused by image motion and its restoration using wavelet transform (EI CONFERENCE) 会议论文 OAI收割 Electronic Imaging and Multimedia Technology IV, November 8, 2004 - November 11, 2004, Beijing, China 作者: Liu G. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 A wavelet-based approach of aerial blurred image restoration is proposed in this article. Image motion is inevitable in photographing for aerospace camera. Though some Image Motion Compensation(IMC) schemes are applied in aerial imaging system the ultimate image will be blurred in certain extent for the existence of IMC residual error while the forward image motion is the key element among all image motions which lead to image blurring. First the course of blurring caused by forward image motion is expressed using wavelet transform and a multiresolution sparse matrix representation of the degeneration model is obtained according to the wavelet transform. Subsequently a regularizing restoration algorithm is deduced from it and which can smoothly restraint the processed result efficiently. In the end the proposed approach is tested in MATLAB. The blurred image is restored using above-mentioned wavelet algorithm conventional contrary filter and Wiener filter algorithm separately. The conclusion that the wavelet-based restoration algorithm is superior to other two approaches is obtained by comparing the restored image's value of mean gradient. The calculating quantity of the wavelet-based blurred image restoration approach isn't large and it has good practicability in the field of image interpretation and aerial survey or drawing.