2011
2011
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Record 1 of
Title:Spectrum reshaping of amplified pulse in silicon nanowaveguide
Author(s):Wu, Jian-Wei(1,2,3); Sarma, Amarendra K.(4); Zhang, Xu-Ping(1)Source: Optics Communications Volume: 284 Issue: 24 DOI: 10.1016/j.optcom.2011.08.010 Published: December 1, 2011Abstract:A device consisting of a cascaded semiconductor optical amplifier (SOA) and silicon on insulator (SOI) optical waveguide is presented to amplify and reshape the frequency spectrum of optical pulses in the picoseconds time duration. Numerical simulations show that the output spectrum of the amplified pulse by SOA can be effectively reshaped by utilizing the SOI waveguide. The length of the SOI waveguide may be judiciously adjusted to significantly reduce the frequency chirp of the output pulse from the SOA resulting in reshaping of the output spectrum. We find that the property of pulse spectrum is sensitive to the input pulse power and its temporal width. ? 2011 Elsevier B.V. All rights reserved. ? 2011 Elsevier B.V. All rights reserved.Accession Number: 20114114423988 -
Record 2 of
Title:Biopsy needle detection in transrectal ultrasound
Author(s):Ayvaci, Alper(1); Yan, Pingkun(2); Xu, Sheng(3); Soatto, Stefano(1); Kruecker, Jochen(3)Source: Computerized Medical Imaging and Graphics Volume: 35 Issue: 7-8 DOI: 10.1016/j.compmedimag.2011.03.005 Published: October-December 2011Abstract:Using the fusion of pre-operative MRI and real time intra-procedural transrectal ultrasound (TRUS) to guide prostate biopsy has been shown as a very promising approach to yield better clinical outcome than the routinely performed TRUS only guided biopsy. In several situations of the MRI/TRUS fusion guided biopsy, it is important to know the exact location of the deployed biopsy needle, which is imaged in the TRUS video. In this paper, we present a method to automatically detect and segment the biopsy needle in TRUS. To achieve this goal, we propose to combine information from multiple resources, including ultrasound probe stability, TRUS video background model, and the prior knowledge of needle orientation and position. The proposed algorithm was tested on TRUS video sequences which have in total more than 25,000 frames. The needle deployments were successfully detected and segmented in the sequences with high accuracy and low false-positive detection rate. ? 2011 Elsevier Ltd.Accession Number: 20113614306990 -
Record 3 of
Title:Theoretical study of all-optical RZ to NRZ format conversion based on cascaded nanoporous silicon waveguides
Author(s):Wu, Jian-Wei(1,2,3,4)Source: Infrared Physics and Technology Volume: 54 Issue: 6 DOI: 10.1016/j.infrared.2011.07.011 Published: November 2011Abstract:In this paper, we present that the strong free carrier absorption and short carrier lifetime in nanoporous silicon waveguide can perform effectively the return-to-zero (RZ) to non-return-to zero (NRZ) format conversion. The project presented consisting of two cascaded millimeters long nanoporous silicon waveguides is numerically simulated and investigated at 5 Gbit/s. Numerical results clearly show that the outcome converted signal (NRZ) at the end of proposed device can be effectively optimized (e.g. clearer extinction ratio - ER, higher Q-factor, and lower bit-error rate - BER) by means of suitably choosing the system parameters such as initial RZ peak level and nanoporous silicon waveguide length. ? 2011 Elsevier B.V. All rights reserved.Accession Number: 20114114413597 -
Record 4 of
Title:Experimental investigation on vibration-reduced characteristics of non-obstructive particle damping for free beam structure
Author(s):Wang, Wei(1); Li, Yuyan(2)Source: Advanced Materials Research Volume: 230-232 Issue: DOI: 10.4028/www.scientific.net/AMR.230-232.867 Published: 2011Abstract:Non-obstructive particle damping is a composite damping technology based on traditional particle damping and impact damping. Being Compared with viscous elastic damping structure, advantage of NOPD is damping characteristic of system improved greatly on the basis of specific whole designing structure and whole mass. The technology has good general vibration-reduced outcome. Beam structure is a common structural element form in engineering application. Because of vibration or instability of beam under external excitation, in this paper, free beam is regarded as an object, and many factors affecting damping characteristic of NOPD are studied, which supplies referring results for engineering application of NOPD. ? 2011 Trans Tech Publications, Switzerland.Accession Number: 20112314028711 -
Record 5 of
Title:FPGA-based multi-bit all state Pseudo-random sequences generator
Author(s):Duan, Yingni(1); Zhang, Haifeng(2)Source: 2011 International Conference on Electronics, Communications and Control, ICECC 2011 - Proceedings Volume: Issue: DOI: 10.1109/ICECC.2011.6066489 Published: 2011Abstract:Aiming at the problems of how to obtain the feedback function of M-sequence (all state sequences) signal and how to generate all the feedback sequence, In this paper we get the nonlinear feedback function by modifing the linear feedback network function of the linear shift register(LFSR) and realize the 12-bit M sequence using FPGA(field programmable gate array). ? 2011 IEEE.Accession Number: 20114714544773 -
Record 6 of
Title:All-optical 40 Gb/s wavelength conversion using hybrid SOI-based MZI and SOAs configuration
Author(s):Wu, Jian-Wei(1,2,3); Lee, Hyun-Shik(2); Lee, El-Hang(2)Source: Optics Communications Volume: 284 Issue: 16-17 DOI: 10.1016/j.optcom.2011.04.045 Published: August 1, 2011Abstract:In this paper, we present a compact combination of silicon-based Mach-Zehnder interferometer (MZI) and semiconductor optical amplifiers (SOAs) to perform all-optical return to zero (RZ)-to-RZ and non-return to zero (NRZ) wavelength conversions at a bit rate of 40 Gb/s. Using the proposed theoretical project, the attractive issue is that converted signals with inverted and noninverted formats can be simultaneously achieved at the same target wavelength. Moreover, both extinction ratio and eye-opening ratio of the converted RZ and NRZ signals can be significantly optimized by judiciously adjusting the system parameters and initial conditions. ? 2011 Elsevier B.V. All rights reserved.Accession Number: 20112314032177 -
Record 7 of
Title:An automatic multi-spectral infrared sea surface temperature radiometer
Author(s):Zhang, Jian(1); Qu, Enshi(1); Cao, Jianzhong(1); Fan, Zheyuan(1); Yang, Hongtao(1)Source: ICEOE 2011 - 2011 International Conference on Electronics and Optoelectronics, Proceedings Volume: 2 Issue: DOI: 10.1109/ICEOE.2011.6013251 Published: 2011Abstract:Sea surface temperature (SST) is an important parameter in many operational and research activities, ranging from weather forecasting to climate research. A multi-spectral infrared sea surface temperature radiometer is a self-calibrating instrument capable of measuring in situ sea surface temperature to an accuracy of better than 0.1 K. This paper describes an instrument with special design features that double channel radiometer with four spectral band pass of 3m5m and 8m12m adapts for autonomous use. The entire instrument infrared optical path is calibrated by viewing two blackbody reference cavities at different temperatures. In this case, the high accuracy of an infrared radiometer is maintained although optical components are moderately contaminated by salt deposition. An newly designed protection shutter that is triggered by a sensitive rain gauge automatically seals the instrument from the external environment in foul weather. ? 2011 IEEE.Accession Number: 20114014386369 -
Record 8 of
Title:A new algorithm for auto-exposure based on the analogy histogram
Author(s):Zhang, Haifeng(1); Cao, Jianzhong(1); Tang, Linao(1); Wang, Huawei(1)Source: Proceedings - 2011 7th International Conference on Computational Intelligence and Security, CIS 2011 Volume: Issue: DOI: 10.1109/CIS.2011.234 Published: 2011Abstract:A calculation of exposure time based on the light measurement often refer to errors in the deepness space detection duo to darkness background of deepness space and over hundreds of kilometers between the camera and the target. However, the use of based on an auto-exposure statistic and compensation method overcome those defects that mentioned before. Consequently, average gray level in the object area could be successfully adjusted to the excellent gray scale. Scientifically speaking, the application of auto-exposure method has benefits to promote the impact of exposure unknown size or light target in the darkness background. ? 2011 IEEE.Accession Number: 20120614746032 -
Record 9 of
Title:Improved image registration based on SIFT features
Author(s):Liu, Jinxia(1); Qiu, Yuehong(1)Source: Proceedings 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011 Volume: Issue: DOI: 10.1109/MEC.2011.6025645 Published: 2011Abstract:SIFT (Scale-invariant feature detection) feature has been applied on image registration. However, how to achieve an ideal matching result and reduce the matching time are the most important steps that we study in our work. The original SIFT algorithm is famous for its abundant feature points, but the final keypoints are so excessive that the matching speed is very slow at the next step of searching for homonymy point-pairs. In this paper, we analyze the performance of SIFT and conquer its deficiencies applying RANSAC arithmetic and Least Squares Method in order to reach a perfect robustness and precision. Experiments with real-world scenes demonstrate that the method can reach a better precision and robustness, which outperforms previously proposed schemes. Compared with conventional localization algorithm, this method makes the precision more stable, which reaches 0.01 pixel, and also reduce the time of image registration. ? 2011 IEEE.Accession Number: 20114114423057 -
Record 10 of
Title:Modulation transfer function online compensation of imaging system in remote sensing satellite
Author(s):Li, Huijuan(1); Qu, Youshan(1); Cheng, Pan(1)Source: 2011 International Conference on Electronics, Communications and Control, ICECC 2011 - Proceedings Volume: Issue: DOI: 10.1109/ICECC.2011.6066285 Published: 2011Abstract:According to the theory of Fourier Optics, an optical remote sensing imaging system is an optical diffraction-limited system and a low-pass filter. CCD or CMOS imaging sensors are low-pass filters as well. Thus, when the optical information of an object or a scene with abundant high-frequency components passes through the remote sensing optical imaging system, the profuse middle-frequency information is attenuated and the rich high-frequency information is lost, which will blur the captured remote sensing images. To solve this problem of the imaging system in the remote sensing satellite, an analog on-line compensating method of the Modulation Transfer Function (MTF) in the imaging system is proposed in this paper. The established method was realized by a hardware analog circuit placed before the A/D converter, which is composed of adjustable low-pass filters with a calculated value of quality factor Q. All the theory analysis, experiment results and application in the remote sensing imaging system of the satellite showed that the proposed method and the realized compensating circuit are capable of improving the MTF of imaging systems and enhancing the middle frequency of blurred video images. ? 2011 IEEE.Accession Number: 20114714544362 -
Record 11 of
Title:Finite element analysis of large mirror based contact theory
Author(s):Wu, Meng Yuan(1); Li, Ying Cai(1)Source: 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011 - Proceedings Volume: Issue: DOI: 10.1109/MACE.2011.5988129 Published: 2011Abstract:This paper describe the finite element analysis of large mirror based on contact theory. After several modules' computing author compared the calculated Result and test result, and make a conclusion that contact analyzing is more accurate than linear analysis for large mirror. ? 2011 IEEE.Accession Number: 20114314454198 -
Record 12 of
Title:Canonical signed digit encoding based optimal design for FIR filters
Author(s):Yue, Qi(1); Ma, Caiwen(1); Wang, Xin(1)Source: Proceedings of 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011 Volume: 2 Issue: DOI: 10.1109/EMEIT.2011.6023152 Published: 2011Abstract:Based on Particle Swarm Optimization (PSO) Algorithm and Canonical Signed Digit (CSD) encoding, an optimal design method for FIR filters is presented in order to reduce the pass-band ripple and power consumption of the integrated circuits. For the slow convergence and invalidate CSD encoding accompanying with the update and mutation operations in PSO, some solutions are given. Simulation results show that the pass-band ripple is reduced and faster convergence is obtained. Applied in the design of cascade filter, the proposed algorithm can greatly reduce the pass-band ripple. ? 2011 IEEE.Accession Number: 20114014403109