中国科学院机构知识库网格系统: 检索

Interpretation of comprehensive two-dimensional gas chromatography data using advanced chemometrics 期刊论文 OAI收割
trac-trends in analytical chemistry, 2014, 卷号: 53, 页码: 150-166
作者: Zeng, Zhongda; Li, Jia; Hugel, Helmut M.; Xu, Guowang; Marriott, Philip J.

收藏 | 浏览/下载：31/0 | 提交时间：2015/11/17

Chemometrics Comprehensive two-dimensional gas chromatography (GC x GC) Data characteristics Data processing Deconvolution Mass spectrometry Multivariate curve resolution (MCR) Multivariate data analysis Orthogonality Signal processing

The application of adaptive enhancement algorithm based on gray entropy in mammary gland CR image (EI CONFERENCE) 会议论文 OAI收割
2012 2nd International Conference on Consumer Electronics, Communications and Networks, CECNet 2012, April 21, 2012 - April 23, 2012, Three Gorges, China
Zhang M.-H.; Zhang Y.-Y.

收藏 | 浏览/下载：34/0 | 提交时间：2013/03/25

Mammary gland is composed entirely of soft tissue with approximate density therefore mammary gland CR medicine radiation image presents a low contrast and slight difference changes may be a manifestation of tumor so it is necessary to enhance mammary gland CR image to improve its visual quality in order to meet the demands of doctor's clinical diagnosis. However the general enhancement algorithms over enhance the contrast and noise due to image details lost aiming at the defects a mammary gland CR medicine image adaptive enhancement arithmetic based on image gray entropy is put forward. The arithmetic adapts dizzy image to magnify selected spatial frequency response in order to enhance the edge details of mammary gland CR images. It can adjust weighted factor K according to image gray characteristics namely pixel gray entropy. Experiments results demonstrate that mammary gland CR image enhanced by the algorithm has abundant details and high signal-to-noise ratio moreover CR image enhanced has good visual effect. So the method is effective and fit for enhancing CR medical radiation image edge details. 2012 IEEE.

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.

Optical signal noise ratio increased by multiplexing algorithm for QSFP+ module (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
Yu H.-C.; Zheng X.-F.; Cheng P.; Yu W.-J.

收藏 | 浏览/下载：43/0 | 提交时间：2013/03/25

In order to increase OSNR (Optical Signal Noise Ratio Secondly Thirdly OSNR) of QSFP+ module the realization steps of the multiplexing algorithm is provided this algorithm is applied in QSFP+ module and the corresponding circuit of host board is designed and the experimental result shows that multiplexing algorithm is able to increase OSNR 2 dB. 2012 IEEE. a multiplexing algorithm is proposed. Firstly the development of optical module and the characteristics of QSFP+ module are illustrated

Analysis on the influence of random vibration on MEMS gyro precision and error compensation (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Li M.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

In order to improve its precision in dynamic environment a Kalman filter was designed. Firstly two sets of random drift data of MEMS gyro were respectively analysed and it was found that the variance of random drift under random vibration significantly increased and its mean also changed. Then calculation results show that attitude angle error under random vibration is 2.6 while in the static test it is 0.25. Analysis on the characteristics of random drift was carried out and it is found that it can be treated as stable normally distributed random signal. Finally a corresponding Kalman filter was designed. The results indicated that after filtering the variance of random drift is reduced to 0.0282 26.4% of pre-filtering and the attitude angle error is reduced to 1.5 57.7% of pre-filtering. The above method can effectively compensate for the attitude angle error of MEMS gyro caused by random vibration. This study can be a reference to the application of low-cost MEMS gyro in aircraft navigation. (2012) Trans Tech Publications Switzerland.

Simulation and measurement of the resonant Schottky pickup 期刊论文 OAI收割
CHINESE PHYSICS C, 2011, 卷号: 35, 页码: 1124-1129
作者: Xu Hu-Shan; Steck, M.; Sanjari, M. S.; Petri, P.; Peschke, C.

|

收藏 | 浏览/下载：23/0 | 提交时间：2018/05/31

resonant Schottky pickup Schottky signal characteristics of the eigenmode TM(010)

Design of thermostat system based on Proteus simulation software (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Han Z.; Song K.

收藏 | 浏览/下载：39/0 | 提交时间：2013/03/25

In order to solve the problem of precise temperature control the thermoelectric cooler (TEC) principle widely used is analyzed for the design of the whole control process and selection of control parameters and then accurate simulation model of the TEC is established in Proteus simulation software. Moreover combined with the traditional circuit simulation model the temperature control loop is designed and the response characteristics of the system are tested using an input signal similar to the unit-step function to achieve the precise temperature control. Simulation results show that the proposed control circuits can precisely convert error signal to output voltage sent to TEC model and TEC model behaves approximately like a two-pole system. The first pole starts at 20mHz and a second pole at 1Hz. 2011 IEEE.

Analyse the angular velocity estimation errors of -- filter based on high sampling rate (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者: Zhang Y.

收藏 | 浏览/下载：31/0 | 提交时间：2013/03/25

In order to get angular velocity of stabilization servo mechanism from angular position sensors -- filter based on high sampling rate was established model and error characteristics were analyzed. With the hypothesis of constant acceleration -- filter and its angular velocity transfer function were deduced. Combing with optimum parameters the effects of and sample rate on the error characteristics were evaluated. According to the requirements of stabilization servo mechanism the frequency characteristics of angular velocity transfer function are analyzed and the filter parameters are designed. The experimental which filter tracked and smoothed sinusoidal signal the results show that when the cutoff frequency of angular velocity loop is 44.9rad/s sampling period and parameters are 0.08ms and 0.01279 respectively the phase leading of angular position is 70. -- filter tracked sinusoidal signals with maximum angular velocity(30/s) and maximum angular acceleration(30/s2) the error of angular velocity estimation was 0.053/s. In the engineering of electro-optical stabilization servo mechanism -- filter can reduce noise effectively and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors. 2011 IEEE.

The angular velocity estimation principal of -- filter based on high sampling rate (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者: Zhang Y.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to get angular velocity of stabilization servo mechanism from angular position sensors -- filter and its angular velocity transfer function were predigested. Combing with optimum parameters -- filter based on high sampling rate was established the effect of and sample rate on filter nature frequency were evaluated. According to the requirements of stabilization platform the principle of steady and transient tracking filter differential were proved. With the hypothesis of constant acceleration the frequency characteristics of angular velocity transfer function were analyzed three-dimensional Kalman filter was simplified and the filter parameters were designed. The results show that when the spectrum of input signal was lower than 6rad/s parameters was 0.02 and sampling period were 0.08ms and 0.1ms respectively the filter can realize differential exactly when the spectrum was 9rad/s the precision was no less than 1.1% the phase leading of angular position was no less than 70 the natural frequency should be higher than the cut-off frequency of stabilization platform was two or three times. In the engineering of electro-optical stabilization servo mechanism -- filter has properties of tracking differential and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors. 2011 IEEE.

Research on infrared dim-point target detection and tracking under sea-sky-line complex background (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: Dong Y.-X.; Zhang H.-B.; Li Y.; Li Y.; Li Y.

收藏 | 浏览/下载：111/0 | 提交时间：2013/03/25

Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms such as adaptive background prediction detecting method. When background has dispersion-decreasing structure the traditional target detection algorithms would be more useful. But when the background has large gray gradient such as sea-sky-line sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature in our opinion from the perspective of mathematics the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore the purpose of the image preprocessing is to reduce the effects from noise also to raise the SNR of image and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics the median filter is used to eliminate noise improve signal-to-noise ratio then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).