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Chinese Academy of Sciences Institutional Repositories Grid
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Development trend and prospect of solid phase extraction technology 期刊论文  OAI收割
CHINESE JOURNAL OF CHEMICAL ENGINEERING, 2022, 卷号: 42, 页码: 245-255
作者:  
Zhang, Chao;  Xing, Huifang;  Yang, Liangrong;  Fei, Pengfei;  Liu, Huizhou
  |  收藏  |  浏览/下载:31/0  |  提交时间:2022/06/15
An analysis of first-time and repeat visitors to Korean national parks from 2007 and 2013 期刊论文  OAI收割
Journal of Mountain Science, 2017, 卷号: 14, 期号: 12, 页码: 2527-2539
作者:  
Yunseon CHOE;  Michael A. SCHUETT;  Kyu-Won SIM
  |  收藏  |  浏览/下载:143/0  |  提交时间:2017/12/07
ThIs Paper ExamIned VIsiTors To Bukhansan NatiOnal Park In Korea Based On First-time And Repeat vIsitatiOn. Bukhansan NatiOnal Park Is Korea's Most Heavily vIsited NatiOnal Park With Annual vIsitatiOn Of Six milliOn VIsiTors In 2015. Data Used In ThIs Article Were Collected On-site In The Park In 2007 And 2013 By The Korea NatiOnal Park Service (Knps). The Study Variables Included Socio-demographics  Travel Behavior  Motivation  And Satisfaction With Park Attributes  Services And Facilities. Data Were Analyzed By Each Study Year For First-time And Repeat Visitors. Results Showed Significant Differences For Both First-time And Repeat Visitors.On Several Socio-demographic  Travel Behavior  And Motivation Variables Within Each Study Year. For Satisfaction With Park Attributes  Facilities And Services  First-time VisiTors Were Significantly Different From Repeat VisiTors On Seven Variables For Both Years. implicatiOns Are Given Regarding Programs And Services To Improve visiTor satisfactiOn And Sustain The Natural  Cultural And HisTorical Resources At Bukhansan nAtional Park And Other nAtional Parks In Korea. Future Research Suggestions Are Provided To Learn More About visiTor Characteristics  StAndards Of Quality And Preferences In The National Parks.  
Research on the key technology of ATP system for free space optical communication (EI CONFERENCE) 会议论文  OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
Meng H.; Liu X.; Zhang B.
收藏  |  浏览/下载:15/0  |  提交时间:2013/03/25
Analysis on present situation of quality and reliability information management of research institute (EI CONFERENCE) 会议论文  OAI收割
2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China
作者:  
Zhang T.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
作者:  
Wang S.-R.;  Lin G.-Y.;  Yu L.
收藏  |  浏览/下载:39/0  |  提交时间:2013/03/25
Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding  the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror  a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror  coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected  and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system  a deuterium lamp  a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.  
Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wu Z.-G.; Wang M.-J.; Han G.-L.
收藏  |  浏览/下载:81/0  |  提交时间:2013/03/25
Being an efficient method of information fusion  image fusion has been used in many fields such as machine vision  medical diagnosis  military applications and remote sensing.In this paper  Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing  including segmentation  target recognition et al.  and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First  the two original images are decomposed by wavelet transform. Then  based on the PCNN  a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength  so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So  the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment  the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range  which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore  by this algorithm  the threshold adjusting constant is estimated by appointed iteration number. Furthermore  In order to sufficient reflect order of the firing time  the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved  each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules  the experiments upon Multi-focus image are done. Moreover  comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.  
Optimum design of the carbon fiber thin-walled baffle for the space-based camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Yan Y.; Gu S.; An Y.; Jin G.
收藏  |  浏览/下载:16/0  |  提交时间:2013/03/25
The thin-walled baffle design of the space-based camera is an important job in the lightweight space camera research task for its stringent quality requirement and harsh mechanical environment especially for the thin-walled baffle of the carbon fiber design. In the paper  an especially thin-walled baffle of the carbon fiber design process was described and it is sound significant during the other thin-walled baffle design of the space camera. The designer obtained the design margin of the thin-walled baffle that structural stiffness and strength can tolerated belong to its development requirements through the appropriate use of the finite element analysis of the walled parameters influence sensitivity to its structural stiffness and strength. And the designer can determine the better optimization criterion of thin-walled baffle during the geometric parameter optimization process in such guiding principle. It sounds significant during the optimum design of the thin-walled baffle of the space camera. For structural stiffness and strength of the carbon fibers structure which can been designed  the effect of the optimization will be more remarkable though the optional design of the parameters chose. Combination of manufacture process and design requirements the paper completed the thin-walled baffle structure scheme selection and optimized the specific carbon fiber fabrication technology though the FEM optimization  and the processing cost and process cycle are retrenchment/saved effectively in the method. Meanwhile  the weight of the thin-walled baffle reduced significantly in meet the design requirements under the premise of the structure. The engineering prediction had been adopted  and the related result shows that the thin-walled baffle satisfied the space-based camera engineering practical needs very well  its quality reduced about 20%  the final assessment index of the thin-walled baffle were superior to the overall design requirements significantly. The design method is reasonable and efficient to the other thin-walled baffle that mass and work environment requirement is requirement harsh. 2011 SPIE.  
The effectiveness of real-time embedded software testing (EI CONFERENCE) 会议论文  OAI收割
2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China
Zhang B.; Shen X.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
Numerical Study on the Spatial and Temporal Characteristics of Water Quality in the Taihu Lake of China 会议论文  OAI收割
Hydrology Conference 2010 (The Changing Physical and Social Environment: Hydrologic Impacts and Feedbacks), San Diego, CA, USA, 2010-10-11~ 2010-10-13
作者:  
Liu QQ(刘青泉)
收藏  |  浏览/下载:28/0  |  提交时间:2010/12/27
Research on the the device of non-angular vibration for opto-electronic platform (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China
An Y.; Song C.-P.; Kuang R.-J.; Jin G.
收藏  |  浏览/下载:39/0  |  提交时间:2013/03/25
The opto-electronic platform is the main equipment for aviation reconnaissance. It is a surveillance system with the function of search  recognition orientation and tracking by opto- electronic instruments. It is made up of opto-electronic instruments which are used to get high quality image  and stabilization tracking system to control stabilization and gesture of platform for exact tracking. The opto-electronic platform purpose is to achieve high quality image. Besides the impact of optic system  the image quality of the system is influenced greatly in the vibration environment. The research worked by Zhao peng which demonstrated the affection caused by angular vibration was worse than which caused by line vibration  and what was multiplied direct ratio with plane altitude. So it is necessary to design a new device which could be used widely and has good angular vibration isolation effect. According to the theory of parallelogram  the non-angular vibration device had been designed with spatial links  and the theory of non-angular vibration was analyzed. The three-dimensional model was set with UG  the analysis was done by ADAMS/vibration software. The acceleration and displacement response of the device in each direction was calculated by inspiriting it with sine wave of the acceleration in three directions  and the stiffness and damp were studied. All the work prove the design principle of the device is reasonable  and the device is adopted to keep the platform motion moving horizontally  at the meantime the device is good at isolating vibration in all directions. 2010 SPIE.