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Zhao M.,Science and Technology on Near Surface Detection Laboratory | Qian H.-M.,Science and Technology on Near Surface Detection Laboratory | Rong Y.-J.,Science and Technology on Near Surface Detection Laboratory | Chen G.,Science and Technology on Near Surface Detection Laboratory
ICALIP 2016 - 2016 International Conference on Audio, Language and Image Processing - Proceedings | Year: 2016

Robust object tracking is a challenging problem as data streams change over time. In this paper we proposed a robust yet fast sparse tracking method using compressive collaborative Haar-like feature space of the model collection including positive (foreground), negative (background) and square templates. As traditional methods, the target is sparsely represented in the models with positive templates only and directly. But, as the complexity computation of sparse representation, we use the compressive Haar-like feature of positive and square templates to deal with occlusion. In order to improve the reliability during the tracking process, we develop a sparsity-based discriminative expression using foreground and background information. The expression with foreground reconstruction error and background reconstruction error is formulated to find the most correct sample. At last, a new update scheme related to the coefficients of templates of our appearance model is presented. Numerous challenging image sequences demonstrate that the proposed algorithm is able to adapt to scale, pose variation, rotation, occlusion and shows excellent real-time performance. © 2016 IEEE.


Guo C.,Science and Technology on Near Surface Detection Laboratory | Junchao S.,Science and Technology on Near Surface Detection Laboratory
ICALIP 2016 - 2016 International Conference on Audio, Language and Image Processing - Proceedings | Year: 2016

Design of high performance power supply for acoustic shock acquisition system is discussed from the perspective of engineering practice of acoustic shock acquisition system. In this connection, design of multi-output power is proposed based on switching regulator. Moreover, by analyzing key components, the problem of high ripple with switching regulator is successfully solved, while power supply efficiency is further improved. The small-sized SMD package is adopted to improve the power density of switching regulator, making it more suitable for limited installation space of acoustic shock acquisition system. In practical applications, the proposal reaches expected design indexes. © 2016 IEEE.


Kai D.,Science and Technology on Near Surface Detection Laboratory | Hao L.,Science and Technology on Near Surface Detection Laboratory | Yichao Z.,Science and Technology on Near Surface Detection Laboratory | Shuang Q.,Science and Technology on Near Surface Detection Laboratory
ICALIP 2016 - 2016 International Conference on Audio, Language and Image Processing - Proceedings | Year: 2016

When intelligent fuse is detecting target acoustic signal, affected by external interference and other factors, the signal may bring on trend term. Existence of trend term may cause direct influence on the accuracy of target acoustic signal, so that it should be removed. In allusion to the problems in existing trend term removal methods, such as trend term type should be assumed in advance, and the calculation process is quite complicated, a smoothness priors approach based method is proposed to remove trend term of target acoustic signal. 3 categories of target acoustic signals were processed in the research. According to the results, the approach is effective in removing trend term of time domain waveform and power spectrum of target acoustic signal. Moreover, the method is simple and efficient, and is applicable to the trend term removal preprocessing of target sound signal. © 2016 IEEE.


Yang M.,Nanjing Southeast University | Yin X.,Nanjing Southeast University | Chen Z.N.,National University of Singapore | Rong Y.,Science and Technology on Near Surface Detection Laboratory | Qian H.,Science and Technology on Near Surface Detection Laboratory
IEEE Antennas and Wireless Propagation Letters | Year: 2016

A planar bow-tie antenna loaded with open stubs is proposed to realize image rejection and gain enhancement for superheterodyne applications. The loading open stubs are two open-circuit double-sided parallel-strip lines symmetrically connected to the feedline of a planar bow-tie antenna, which functions as a bandstop filter in frequency band lower than the operating frequency to reject image interference and simultaneously as a reflector across the operating frequency band to enhance the antenna gain. Simulated results show that the realized gain of the proposed antenna in the main radiation direction is suppressed by 25 dB at the image frequency and is enhanced by about 3 dB at the operating frequency compared to that of an unloaded antenna. Good agreements between the simulated and the measured results have been observed. © 2015 IEEE.


Yang C.H.,Nanjing University of Information Science and Technology | Shen G.Z.,Nanjing University of Information Science and Technology | Ao Z.M.,Guangdong University of Technology | Xu Y.W.,Science and Technology on Near Surface Detection Laboratory
Materials Research Express | Year: 2016

Using the transfer matrix method, the carrier tunneling properties in graphene superlattice generated by the Thue-Morse sequence and Kolakoski sequence are investigated. The positions and strength of the transmission can be modulated by the barrier structures, the incident energy and angle, the height and width of the potential. These carriers tunneling characteristic can be understood from the energy band structures in the corresponding superlattice systems and the carrier's states in well/barriers. The transmission peaks above the critical incident angle rely on the carrier's resonance in the well regions. The structural diversity can modulate the electronic and transport properties, thus expanding its applications. © 2016 IOP Publishing Ltd.


Qi H.,Nanjing Southeast University | Yin X.,Nanjing Southeast University | Liu L.,Nanjing University of Posts and Telecommunications | Rong Y.,Science and Technology on Near Surface Detection Laboratory | Qian H.,Science and Technology on Near Surface Detection Laboratory
IEEE Antennas and Wireless Propagation Letters | Year: 2016

This letter introduces an effective solution for improving isolation between closely spaced patch antennas. A satisfactory isolation is realized by three interdigital lines that excite an orthogonal polarization mode on the adjacent patch. A two-patch array is simulated and fabricated to verify the decoupling effectiveness of the proposed structure. The investigations of the electric field and current distributions reveal the working mechanism of the proposed structure. The experimental results show that the achieved isolation is better than 20 dB, and the maximum isolation enhancement is 24.7 dB, with a compact edge-to-edge separation of just 0.07λ0. Moreover, the proposed structure can also be applied for the decoupling of a multielement patch array. © 2002-2011 IEEE.


Shen G.,Nanjing University of Information Science and Technology | Xu Y.,Science and Technology on Near Surface Detection Laboratory | Liu B.,Nanjing University of Information Science and Technology
Desalination and Water Treatment | Year: 2016

Carbon materials are effective for removal of both toxic inorganic and organic substances. In this study, a novel magnetic mesoporous carbon aerogel which combined high specific surface area, adsorption capacity and magnetic property of Fe3C was prepared by citrate sol-gel method. The as-prepared samples were characterized by powder X-ray diffraction, TEM, scanning electron microscope, and BET methods. Results show that the aerogel has the specific surface and average pore size of 290 m2/g and 2.7 nm, respectively. Magnetic Fe3C nanoparticles were dispersed uniformly in carbon matrix and exhibit excellent response to an external magnetic field. As a result, the adsorbent can be easily separated from solution using an external magnetic field. Batch experimental results on As(V) removal showed that the adsorption kinetics and isotherm data were fitted well by a pseudo-second-order model and a Freundlich model, respectively. The monolayer adsorption capacity (qm) of the adsorbent was calculated to be 56.2 mg/g at pH 7.0. The excellent uptake capability of the magnetic mesoporous materials make it be potentially attractive materials for removal of hazardous substances from water. © 2016 Balaban Desalination Publications. All rights reserved.


PubMed | Wuhan University and Science and Technology on Near Surface Detection Laboratory
Type: Journal Article | Journal: Sensors (Basel, Switzerland) | Year: 2016

Based on the dynamic nuclear polarization (DNP) effect, an alternative design of an Overhauser geomagnetic sensor is presented that enhances the proton polarization and increases the amplitude of the free induction decay (FID) signal. The short-pulse method is adopted to rotate the enhanced proton magnetization into the plane of precession to create an FID signal. To reduce the negative effect of the powerful electromagnetic interference, the design of the anti-interference of the pick-up coil is studied. Furthermore, the radio frequency polarization method based on the capacitive-loaded coaxial cavity is proposed to improve the quality factor of the resonant circuit. In addition, a special test instrument is designed that enables the simultaneous testing of the classical proton precession and the Overhauser sensor. Overall, comparison experiments with and without the free radical of the Overhauser sensors show that the DNP effect does effectively improve the amplitude and quality of the FID signal, and the magnetic sensitivity, resolution and range reach to 10 pT/Hz 1 / 2 @1 Hz, 0.0023 nT and 20-100 T, respectively.


Sun H.-T.,National University of Defense Technology | Chang W.-G.,National University of Defense Technology | Liu Z.-H.,Science and Technology on Near Surface Detection Laboratory
2015 IEEE International Conference on Communication Problem-Solving, ICCP 2015 | Year: 2015

Throwing-mine detection is a typical problem of low RCS (radar cross section) targets detection in heavy clutter, in which the high false alarm rate is a difficult problem. Classical CFAR (Constant False Alarm Rate) detection algorithm only utilizes the image contrast characteristics, in the case of low SNR (Signal to Noise Ratio), a large number of false alarms generates. In order to further reduce false alarm rate, CFAR-IHP (Constant False Alarm Rate-Internal Hermitian Product) detection algorithm is proposed in this paper. CFAR-IHP is based on CFAR and target azimuth coherence characteristic, therefore, we first get the sub-aperture image sequence to extract target azimuth information by the sub-aperture processing algorithm for SAR image. Lastly, based on Ku-band SAR data, we use CFAR-IHP (Constant False Alarm Rate-Internal Hermitian Product) algorithm to detect the targets, experimental results show that the method further eliminate the clutter and the azimuth coherence helpfully reduces the false alarms.


Jia G.,National University of Defense Technology | Chang W.,National University of Defense Technology | Zhang Q.,National University of Defense Technology | Luan X.,Science and Technology on Near Surface Detection Laboratory
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2016

Regarding the two-dimensional (2-D) imaging processing of circular synthetic aperture radar (CSAR), the motion compensation (MOCO) in the frequency domain is not fully developed. To perform the MOCO for CSAR data in the frequency domain, a novel three-step strategy is presented in this paper. The motion error model is established first, and it is found that a difficulty of MOCO for CSAR lies in the space variance of the motion errors. Specifically, according to the proposed MOCO strategy, this first step is space-invariant MOCO, the second step is space-variant MOCO in the range-compressed angular-wavenumber domain with respect to subaperture data, and the last step is the autofocus operation in the 2-D wavenumber domain after the polar format resampling. Eventually, the complete MOCO flowchart is obtained. Simulation and experimental tests verify that the proposed motion error model is valid and the three-step MOCO strategy can remove motion errors accurately and figure out well-focused CSAR images. © 2008-2012 IEEE.

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