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	Optimization design of heat exchanger in an irreversible regenerative Brayton cycle system 期刊论文 OAI收割 APPLIED THERMAL ENGINEERING, 2013, 卷号: 58, 期号: 1-2, 页码: 77-84 作者: Guo, Jiangfeng; Huai, Xiulan 收藏 \| 浏览/下载：24/0 \| 提交时间：2015/10/27 Revised entropy generation number Optimization design Brayton cycle Heat exchanger Net output work
	Analysis of an Air Powered Engine System Using a Multi-Stage Radial Turbine 期刊论文 OAI收割 ENTROPY, 2013, 卷号: 15, 期号: 4, 页码: 1186-1201 作者: Zhang, Xuehui; Chen, Haisheng; Yan, Xiaohui; Zhang, Xinjing; Tan, Chunqing 收藏 \| 浏览/下载：24/0 \| 提交时间：2015/10/27 thermodynamic analysis radial turbine thermal efficiency exergy efficiency work output
	Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China 作者: Li G.-N.; Jin L.-X.; Zhang R.-F.; Wang W.-H.; Li G.-N. 收藏 \| 浏览/下载：51/0 \| 提交时间：2013/03/25 According to the area CCD camera of characteristics such as high resolution capacity and high frame frequency this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly according to the work principle of the area CCD FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip real time image compression and the high speed area CCD are realized. Finally by detecting the analog signal of the area CCD output the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15 the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated which reduces the data transmission between them and improves systematic integration degree.
	The sequence measurement system of the IR camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang H.-B.; Han H.-X.; Geng A.-H. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Currently the IR cameras are broadly used in the optic-electronic tracking optic-electronic measuring fire control and optic-electronic countermeasure field but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras the sequence measurement system of the IR camera is designed and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system and the precise sequence of the IR camera's output signal has been achieved the detailed document of the IR camera has been supplied to the continuous image transmission system image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part LVDS input interface part FPGA part CameraLink output interface part and etc thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system and because the image processing card and image memory card always use the CameraLink interface as its input interface style the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system the sequence measurement program the pixel clock modification the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by the verilog language combining the SignalTap tool on line observation can count the line numbers in one frame pixel numbers in one line and meanwhile account the line offset and row offset of the image. Aiming at the complex sequence of the IR camera's output signal the sequence measurement system of the IR camera accurately measures the sequence of the project applied camera supplies the detailed sequence document to the continuous system such as image processing system and image transmission system and gives out the concrete parameters of the fval lval pixclk line offset and row offset. The experiment shows that the sequence measurement system of the IR camera can get the precise sequence measurement result and works stably laying foundation for the continuous system. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	All-solid-stated laser controller design based on digital optical feedback (EI CONFERENCE) 会议论文 OAI收割 Lasers in Material Processing and Manufacturing II, November 10, 2004 - November 12, 2004, Beijing, China 作者: Liu L.; Wang J.-L.; Wang J.-L.; Liu L. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 The new design about a CW digital all-solid-stated LD pumped Nd:YVO 4 controller is introduced. The stable output power of this digital laser controller which adopts Digital Signal Processor(TMS320C31) is approximately 20mW. The whole system is composed of constant- current source protection circuit pulse-width modulation circuit Si-photo-detector and amplified circuit and Digital Signal Processor control system etc. In terms of error deviation Based on nonlinear control curves of LD power output by Si-photo-detector the region control can be obtained by means of the PID control algorithm in the software platform that is error amendment and high stability laser power output can be achieved. And the precision of temperature control can reduce from 0.2C to 0.04C. By adopted integral separated mode PID control algorithm the LD output power instability ( %) down to 2%. By way of adopting the new digital design the work to protect the laser diode including the continuous adjustable output power with high accuracy and stability is easily obtained. The internal-external modulation control of the laser power based on digital optical feedback can be accomplished with stable power output. At last the bringing reasons of noise are analyzed and the solving methods are put forward in this paper.
	Research on LD-Pumped dual wavelength Nd:YAG Laser with high beam quality for machining (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang G.; Zhang G.; Zhang G.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Considering laser medium thermal lens effect and thermal focal length changes with pumping power conventionally lasers are designed to operate in the middle of thermal stable zones where the fundamental mode size is insensitive to thermal perturbation while this method seems impossible when large fundamental mode size is required. Through self-select mode cavity lasers are designed to work at the border of stable zone instead where large fundamental mode size in gain media can be reached. With increase of pumping power and self-aperture mode-selective effect mode size would grow up automatically to a certain value suitable for monomode resonance. With double 180 W pump modules acoustic Q-switch and LBO external frequency-doubled over 28 W which M2 equals 4.5 quasi-CW output green laser and 52W 1.064 um IR output is obtained simultaneity. With the insertion or not of the harmonic separator by footswitch high beam quality green IR and green IR lasers are obtained conveniently.