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	Chameleon dark energy can resolve the Hubble tension 期刊论文 OAI收割 PHYSICAL REVIEW D, 2021, 卷号: 103, 期号: 12, 页码: L121302 作者: Cai, Rong-Gen; Guo, Zong-Kuan; Li Li; Wang, Shao-Jiang; Yu, Wang-Wei \| 收藏 \| 浏览/下载：42/0 \| 提交时间：2021/09/27 BARYON ACOUSTIC-OSCILLATIONS DECELERATION-ACCELERATION TRANSITION RED GIANT BRANCH COSMOLOGICAL PARAMETERS MEASUREMENT CONSTRAINTS CEPHEID STANDARDS COSMIC DISTANCES SOUND-HORIZON DATA RELEASES FINAL DATA
	Communication synchronization in wireless optical link (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China 作者: Guo J.; Guo J.; Wang H.; Wang H.; Wang H. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 An FPGA based transceiving synchronization method is demonstrated for Free Space Optical (FSO) communication system which is discussed separately as the transmitting protocol and the receiving protocol. During the discussion of these two parts the co-operation of them is also discussed. The transmitting protocol interfaces the outer input data with a parallel port buffers the input data encodes the input data stream serializes the parallel data and outputs the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The receiving protocol filters and synchronizes the input serial data stream parallels the serial data stream decodes the input data checks received error handles transmission exception and interfaces 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 users 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 a working solution at a certain bit rate scale. 2012 IEEE.
	A small thickness measurement system based on PSD and FPGA (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: Guo J.; Guo J.; He X. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Considering that the requirement of industrial manufacture An AT89S51 singlechip works as the core processor of the system. By two laser triangulation a small thickness measurement system based on PSD and FPGA is presented. It takes S3931 PSD of one dimension as position detection device A FPGA produces logic control signals for the whole system the small displacement is converted to differential voltages which is made by Hamamatsu in Japan and after amplification and A/D transformation 8-bit parallel data is send to singlechip from FPGA by external interrupts and the final calculation results output to the LCD display module. After digital micro meter calibration we get the small thickness. Experiments show that the detection accuracy of the system is not less than 10um.
	Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise for a seeker electro-driven with a concentric glass dome the large errors will decrease the picking pointing and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure manufacture installation and vibration coming from working environment. In this paper the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case the diameter is 120mm and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker and at the same time the errors resulting from installation were considered too. Based on calculating the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper and finally the maximum gimbal displacement error reduced to 0.1mm which is acceptable corresponding to the picking pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Multi-channel high-speed TDICCD image data acquisition and storage system (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China 作者: Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 For multi-channel high-speed image data of certain space remote sensing camera this paper proposed a new image data acquisition and storage system. First of all the system uses Field-Programmable Gate Array(FPGA) controlling synchronous dynamic random access memory(SDRAM) array to realize the cache of image data then according to the received commands sends certain channel's image data to the acquisition card to write the image data into SCSI hard disk and implements the final storage. A Time Delay Integral Charge Couple Device(TDICCD) image data acquisition and storage system with five channels is developed pixel clock rate is up to 96MHz total effective data rate is up to 2.88Gb/s single channel storage depth is up to 7810 lines. The experimental results indicate that this system work stably high effectively which can meet the requirement of acquisition and storage of multi-channel high-speed TDICCD image data. 2010 IEEE.
	Color videos' multichannel combination for bandwidth reduction and fast frequency domain processing (EI CONFERENCE) 会议论文 OAI收割 2nd International Workshop on Education Technology and Computer Science, ETCS 2010, March 6, 2010 - March 7, 2010, Wuhan, Hubei, China 作者: Li S. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 The real color video consumes much transfer bandwidth and the resource of the hardware. A new approach is introduced to process the real color video images in real-time using color components combination to fit to the limited transmission bandwidth. The Y U V planes of video images are packed to construct a 2 dimensional complex array. Through the decomposition of frequency domain the Y U V frequency can be got respectively by performing Fourier transform a time on the specific complex array. These frequencies can be filtered to generate the final filtered images. The experiment results show that the proposed algorithm is 3X speed compared to the traditional algorithm and it reduces 1/3 bandwidth of video data stream. 2010 IEEE.
	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：58/0 \| 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 MLP-PNN neural network for CCD image super-resolution in wavelet packet domain (EI CONFERENCE) 会议论文 OAI收割 2008 International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2008, October 12, 2008 - October 14, 2008, Dalian, China Zhao X.; Fu D.; Zhai L. 收藏 \| 浏览/下载：68/0 \| 提交时间：2013/03/25 Image super-resolution methods process an input image sequence of a scene to obtain a still image with increased resolution. Classical approaches to this problem involve complex iterative minimization procedures typically with high computational costs. In this paper is proposed a novel algorithm for super-resolution that enables a substantial decrease in computer load. First decompose and reconstruct the image by wavelet packet. Before constructing the image use neural network in place of other rebuilding method to reconstruct the coefficients in the wavelet packet domain. Second probabilistic neural network architecture is used to perform a scattered-point interpolation of the image sequence data in the wavelet packet domain. The network kernel function is optimally determined for this problem by a MLP-PNN (Multi Layer Perceptron - Probabilistic Neural Network) trained on synthetic data. Network parameters dependent on the sequence noise level. This super-sampled image is spatially Altered to correct finite pixel size effects to yield the final high-resolution estimate. This method can decrease the calculation cost and get perfect PSNR. Results are presented showing the quality of the proposed method. 2008 IEEE.