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Chinese Academy of Sciences Institutional Repositories Grid
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Rapid Micro-Patterning of a Conductive PANI/MWNTs-Polymer Composite Using an Optically-induced Electrokinetics Chip 会议论文  OAI收割
IEEE Nanotechnology Materials and Devices Conference (IEEE NMDC), Honolulu, HI, OCT 16-19, 2012
作者:  
Liu N(刘娜);  Liang WF(梁文峰);  Mai, John D.;  Dong ZL(董再励);  Li WJ(李文荣)
收藏  |  浏览/下载:38/0  |  提交时间:2013/12/26
A flexible, dynamically programmable and low-cost method applicable to micro-patterning of a conductive polymer/carbon nanotube composite solution is significant due to the potential applications in many areas. This paper demonstrates a new micro-patterning method for fabricating electrodes from a conductive polyaniline (PANI)/MWNT composite using an optically-induced electrokinetics (OEK) chip. This method quickly patterns flexible polymeric electrodes with different geometries when a square waveform signal with amplitudes from 16-20 Volts and frequencies from 20-30 kHz are applied. The geometric dimensions of the electrodes can be varied dynamically by controlling the size and exposure time of the light pattern. The surface morphology of electrodes patterned by this method is scanned by an atomic force microscope (AFM) and a scanning electron microscope (SEM) which show that the electrodes are uniform and continuous. Furthermore, the geometric dimensions and resistances of the electrodes are measured and analyzed. Experimental results reveal that the relationship between the resistance and geometries of the electrodes obey Ohm's law and the resistivity of the electrodes is about 0.03 Omega.m.  
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.  
Simulation and experiment of the static FTIR based on micro multi-step mirrors (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
作者:  
Liang Z.-Z.;  Zhang J.;  Zhang J.;  Zhang J.;  Zhu W.-B.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
In recent years  Fourier transform spectrometer (FTS) with small size and low mass is required in many applications with growing need for real-time and small platform spectral detection. In this paper  a micro Fourier transform infrared spectrometer (FTIR) based on spatial modulation mode was designed. This spectrometer has the advantages of high stability and simplified configuration. It also promises optical path differences (OPD) with high precision  as MOEMS technology is used in manufacturing the key components. The simulation and the experiments with regard to this FTIR configuration have been done. Firstly  the diffraction effect of the micro multi-step mirrors (MMSMs) is studied. We discuss the influence to the reversed spectrum by different mirror widths and different diffraction distances. Secondly  we simulate and analyze the influence of the source solid angle to the spectral resolution. Thirdly  we set up the theoretical model of the collimation error which is mainly from the defocus of the optical system and analyze the result caused by the collimation error. Fourthly  a new discrete Fourier transform arithmetic using least-squares cosines progression (LSCP) is proposed which can reconstruct the spectrum with nonuniform sampled signals. Finally  the MMSMs are fabricated used the MOEMS technology and the structural parameters are tested. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Citizen-generated spatial data and information: Risks and opportunities 会议论文  OAI收割
2011 IEEE International Conference on Intelligence and Security Informatics, ISI 2011,, Beijing, China, July 10, 2011 - July 12,2011
Mooney, Peter; Sun, Huabo; Corcoran, Padraig; Yan, Lei
收藏  |  浏览/下载:22/0  |  提交时间:2014/12/07
Layered graphene on surface of carbon fiber (EI CONFERENCE) 会议论文  OAI收割
8th International Vacuum Electron Sources Conference, IVESC 2010 and NANOcarbon 2010, October 14, 2010 - October 16, 2010, Nanjing, China
作者:  
Wang W.;  Wang W.
收藏  |  浏览/下载:41/0  |  提交时间:2013/03/25
Carbon nanomaterials have attracted considerable attention and interest owing to the unique physical and chemical properties. Such as nanodiamonds  carbon nanofibers  carbon nanotubes (CNTs)  graphene and so on  they all have potential applications as field electron emission materials  electrode materials  storage hydrogen materials and composite materials. In this paper we reported the growth of layered graphene(LG) on carbon fibers surface. The LG synthesized on carbon fibers may have potential applications in many fields. For example  using to improve the electric conductivity and chemical stability of carbon fibers substrate  the grown LG can be applied as high performance capacitor  battery  field emission electron source  hydrogen storage owing to large ratio surface and hybrid multiscale composite. 2010 IEEE.  
An intelligent video surveillance 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
Gao S.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
This paper presents an intelligent video surveillance system. The system is composed of one or more nodes flexibly according to the application scenarios such as private properties  banks and museums. Each node is an autonomous vision-based device capable to perform intelligent tasks. It is able to digitize and compress the acquired analog video signals in MPEG-4 standard and then transmit the compressed video stream to the control center. At the same time  the node makes use of a statistical approach for real-time detecting moving object and online alarm generation to enable a single human operator to monitor activities over a complex area using a distributed network of active video sensors. The node is implemented on a platform with high performance to ensure that the algorithm is able to run in real-time. Applications demonstrate that the intelligent system has an excellent performance in many scenarios to help people make decisions more accurately and rapidly. 2010 IEEE.  
Analysis of laser jamming to satellite-based detector (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:  
Guo L.-H.;  Guo R.-H.;  Wang S.-W.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
The reconnaissance satellite  communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites  anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups  but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large  it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain  so laser disturbing satellite detector is possible. In order to determine its feasibility  the theoretical analyses and experimental study are carried out in the paper. Firstly  the influence factors of laser disturbing satellite detector are analyzed in detail  which including laser power density on the surface of the detector after long distance transmission  and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit  but dependence on the following parameters: laser average power in the ground  laser beam quality  tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly  the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away  which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally  using the theoretical model  the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2  which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser  even decrease laser average power  it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.  
Micro assembled fourier transform spectrometer (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Liang J.-Q.;  Zhang J.;  Zhang J.;  Zhang J.;  Wang B.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
With the trend of minimization of Fourier transform spectrometer (FTS) which is particularly pronounced in many applications  a model of a micro FTS with no moving parts is proposed and analyzed. During analyzng  the gradients which mainly introduce phase error are accounted. Based on these assumptions and the improved Mertz phase correcting method  the spectrum of signal is simulated with real extended light source. The resolution can be up to 3.43nm@800nm  with high signal-to-noise ratio (SNR) limiting resolving ability 6.8dB. In addition  the fabrication method of components are illuminated and demonstrated  which can not only make it bear some advantages over conventional micro dispersive spectrometers  but also afford some new concepts on the design of spectrometers with improved performance. 2009 SPIE.  
LED optical engine based on rectangular CPC for micro-projection display (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Meng Z.;  Meng Z.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
With applications in digital display  consumer electronics  medicine  automotive lighting  traffic signals  and general illumination  the light-emitting diode (LED) is the world's most efficient light source being mass produced today[1]. However  high cost is the main factor restricting widespread application of LED lighting  and the packaging is the most expensive aspect of LED products. Light emitting diodes (LED) are regarded as the most important light sources in solid-state lighting for their advantages in energy efficiency  long life  vivid colors  high reliability  environmental protection  safety and multiple applications. However  application of LEDs in projection display exist many questions such as low illuminance uniformity and low energy efficiency by reason of luminescence distribution and constructure specificity for LED  the study on application of LED in the micro-projection display and projection display is reported[2-8]. Considering the question mensioned above the rectangular CPC(Compound Parabolic Concentrator) system with three-color LED is applied in the projection display. 2009 SPIE.  
Analysis of spectrum narrowing of diode laser bar (EI CONFERENCE) 会议论文  OAI收割
Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China
作者:  
Liu Y.;  Wang L.;  Wang L.;  Wang L.;  Liu Y.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
Laser diode bar (LDB) are used increasingly often for many applications  but spectral bandwidth of LDB are generally approximately 2-4nm  far too wide for many demanding applications  e.g. spin-exchange optical pumping  terahertz generation  and lidar. External-cavity feedback can improve the spectral properties of LD or LDB. However  spectrum narrowing of LDB is more difficult than that of LD. Bar curvature (i.e. "smile") produced in the manufacturing process affects the spectrum narrowing greatly. By geometrical optics approach and ORIGIN software  smile which can be corrected by plano-convex cylindrical lens is simulated and the result is in good agreement with experiment. The selection of grating which is also a critical factor of spectrum narrowing will be stated. Finally  an external cavity consisting of fast axis collimator  two plano-convex cylindrical lens and a diffraction grating is used. The scheme is implemented on a 19-element LDB and yields 3-fold reduction in spectral linewidth under the situation that all optical elements in the system which are not optimized. Further  we use a slit in the experiment and analyze the spectrum narrowing of each element in LDB.