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Theory of Dynamics In-Phase Locking and Quasi-Period Synchronization in Two Mutually Coupled Multi-Quantum-Well Lasers 被引量:1
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作者 YAN Sen-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期481-488,共8页
Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but... Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but detuning, in detain. It is proved that the coupling level determines stability of the lasers by analyzing the eigenvalue equation. Critical case of locking is discussed via the phase difference equation. Quasi-period and stable states in the two lasers are investigated via varying the current, detuning and coupling level. 展开更多
关键词 in-phase locking SYNCHRONIZATION multi-quantum-well laser COUPLING
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Characteristic Surface Oxide Film Cracking Behavior of a Fe-Ni-Cr Alloy under In-phase and Out-of-phase Thermo-mechanical Fatigue
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作者 何庆复 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期850-853,共4页
The surface oxide film cracking behavior of Fe-30Ni-20Cr alloy under in-phase and out-of-phase synchronizing thermal cycling with mechanical cycling was studied.Surface oxide film cracking along the grain boundary und... The surface oxide film cracking behavior of Fe-30Ni-20Cr alloy under in-phase and out-of-phase synchronizing thermal cycling with mechanical cycling was studied.Surface oxide film cracking along the grain boundary under in-phase overlapping was creep predominant fracture mechanisms.Strongly induced slip lines preceding were accompanied by the surface oxide film cracking under Out-of phase,and the shear cracking was dominant mode.Negative mean stress could counteract a part of the tensile component of alternative stress,so as to delay the cracking process under in-phase,but positive mean stress overlapping the tensile alternative stress could accelerate the cycling cracking process under out-of-phase. 展开更多
关键词 oxide film cracking in-phas out-of-phase cycling temperature cycling loading OVERLAPPING
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On the Sub-Critical Bifurcation of Anti-Phase and In-Phase Synchronized Vortex Shedding Forms
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作者 Yih Ferng Peng 《Journal of Modern Physics》 2013年第5期89-95,共7页
Transition of flows past a pair of side-by-side circular cylinders are investigated by numerical simulations and the bifurcation analysis of the numerical results. Various flow patterns behind the cylinder-pair have b... Transition of flows past a pair of side-by-side circular cylinders are investigated by numerical simulations and the bifurcation analysis of the numerical results. Various flow patterns behind the cylinder-pair have been identified by the gap ratio (G) and Reynolds number (Re). This study focus on transition of in-phase and anti-phase vortex shedding synchronized forms. A nested Cartesian-grid formulation, in combination with an effective immersed boundary method and a two-step fractional-step procedure, has been adopted to simulate the flows. Numerical results reveal that the in-phase and anti-phase vortex shedding flows at Re = 100 can co-exist at 2.08 ≤G≤ 2.58. Hysteresis loop with increasing/decreasing G at constant Reynolds number Re = 100 is reported. 展开更多
关键词 in-phase VORTEX SHEDDING Anti-phase VORTEX SHEDDING Hysteresis
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Design of Seven-core Photonic Crystal Fiber with Flat In-phase Mode for Yb: Fiber Laser Pumping
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作者 Ruijuan Dong Peiguang Yan +4 位作者 Gelin Zhang Huiquan Li Shuangchen Ruan Huifeng Wei Jie Luo 《Optics and Photonics Journal》 2013年第2期197-201,共5页
We numerically investigate the seven-core photonic crystal fiber (PCF) with the zero dispersion wavelength designed in the range of 1000 - 1080 nm, particularly suitable for the ytterbium-doped fiber laser pumping. Al... We numerically investigate the seven-core photonic crystal fiber (PCF) with the zero dispersion wavelength designed in the range of 1000 - 1080 nm, particularly suitable for the ytterbium-doped fiber laser pumping. Also, the PCFs are well designed for obtaining a flat in-phase mode by carefully adjusting the diameter of inner layer six holes, and the corresponding empirical values of fiber structure are summarized and listed. The variations of inner six holes to the amplitude of in-phase mode are further investigated, and our results show that a better tolerance can be achieved in the fiber structures with lower filling ratio configuration. 展开更多
关键词 Photonic Crystal Fiber (PCF) in-phase MODE (IPM) SUPERCONTINUUM Generation (SCG)
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Gain-Enhanced Metamaterial Based Antenna for 5G Communication Standards 被引量:10
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作者 Daniyal Ali Sehrai Fazal Muhammad +3 位作者 Saad Hassan Kiani Ziaul Haq Abbas Muhammad Tufail Sunghwan Kim 《Computers, Materials & Continua》 SCIE EI 2020年第9期1587-1599,共13页
Metamaterial surfaces play a vital role to achieve the surface waves suppression and in-phase reflection,in order to improve the antenna performance.In this paper,the performance comparison of a fifth generation(5G)an... Metamaterial surfaces play a vital role to achieve the surface waves suppression and in-phase reflection,in order to improve the antenna performance.In this paper,the performance comparison of a fifth generation(5G)antenna design is analyzed and compared with a metamaterial-based antenna for 5G communication system applications.Metamaterial surface is utilized as a reflector due to its in-phase reflection characteristic and high-impedance nature to improve the gain of an antenna.As conventional conducting ground plane does not give enough surface waves suppression which affects the antenna performance in terms of efficiency and gain etc.These factors are well considered in this work and improved by using the metamaterial surface.The radiating element of the proposed metamaterial based antenna is made up of copper material which is backed by the substrate,i.e.,Rogers-4003 with a standard thickness,loss tangent and a relative permittivity of 1.524 mm,0.0027 and 3.55,correspondingly.The proposed antenna with and without metamaterial surface operates at the central frequency of 3.32 GHz and 3.60 GHz,correspondingly.The traditional antenna yields a boresight gain of 2.76 dB which is further improved to 6.26 dB,using the metamaterial surface.The radiation efficiency of the proposed metamaterial-based 5G antenna is above 85%at the desired central frequency. 展开更多
关键词 Metamaterial surface in-phase reflection 5G high gain
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High-performance compensation scheme for frequency-dependent IQ imbalances in OFDM transmitter and receiver 被引量:4
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作者 Yan Liang Feng Shu +1 位作者 Yijin Zhang Junhui Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期204-208,共5页
An efficient compensation scheme combining a timedomain Gaussian elimination(GE) channel estimator and a frequency-domain GE equalizer is proposed for orthogonal frequency division multiplexing(OFDM) systems with ... An efficient compensation scheme combining a timedomain Gaussian elimination(GE) channel estimator and a frequency-domain GE equalizer is proposed for orthogonal frequency division multiplexing(OFDM) systems with frequencydependent in-phase and quadrature-phase(IQ) imbalances at both transmitter and receiver.Compared with the traditional least square and least mean square compensation schemes,the proposed compensation scheme achieves the same bit error rate as the ideal IQ branches by using only two training OFDM symbols instead of about 20 OFDM symbols. 展开更多
关键词 in-phase and quadrature-phase(IQ) imbalance time domain frequency domain least square least mean square Gaussian elimination(GE).
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A new model for life prediction of GH4133 under TMF conditions 被引量:2
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作者 JianguoWang HongyingWang +2 位作者 ShipingXu LianqingWang YonglinKang 《Journal of University of Science and Technology Beijing》 CSCD 2002年第4期287-291,共5页
Thermal mechanical cyclic strain tests were carried out under in-phase andout-of-phase conditions on a Nickel-base Superalloy GH4133 in the temperature range of 571-823 degC. Based on analyzing the present models of T... Thermal mechanical cyclic strain tests were carried out under in-phase andout-of-phase conditions on a Nickel-base Superalloy GH4133 in the temperature range of 571-823 degC. Based on analyzing the present models of TMF (thermal mechanical fatigue) life prediction, a newmodel for predicting nickel-base superalloy TMF lifetime was proposed. TMF life of superalloy GH4133was calculated accurately based on the new model. Experimental TMF life has been compared with thecalculated results and all results fall in the scatter band of 1.5. The calculating results showthat the new model is not only simple, but also precise. This model will play great roles as lifeprediction of the metal materials and the engineering components subjected to non-isothermal serviceconditions. 展开更多
关键词 thermal mechanical fatigue life production Nickel-base superalloy fatigue lifetime prediction model in-phase out-of-phase
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Decoupled estimation of frequency-dependent IQI and channel for OFDM systems with direct-conversion transceivers 被引量:1
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作者 Yan Liang Rongfang Song +2 位作者 Fei Li Xueyun He Lihua Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期435-441,共7页
The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the t... The in-phase and quadrature-phase imbalance (IQI) is one of the major radio frequency impairments existing in orthogonal frequency division multiplexing (OFDM) systems with direct-conversion transceivers. During the transmission of the communication signal, the impact of IQI is coupled with channel impulse responses (CIR), which makes the traditional channel estimation schemes ineffective. A decoupled estimation scheme is proposed to separately estimate the frequency-dependent IQI and wireless channel. Firstly, the generalized channel model is built to separate the parameters of IQI and wireless channel. Then an iterative estimation scheme of frequency-dependent IQI is designed at the initial stage of communication. Finally, based on the estimation result of IQI, the least square algorithm is utilized to estimate the channel-related parameters at each time of channel variation. Compared with the joint estimation schemes of IQI and channel, the proposed decoupled estimation scheme requires much lower training overhead at each time of channel variation. Simulation results demonstrate the good estimation performance of the proposed scheme. 展开更多
关键词 direct-conversion transceivers frequency-dependent in-phase and quadrature-phase imbalance (IQI) orthogonal frequency division multiplexing (OFDM) decoupled estimation
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Single-trial EEG classification using in-phase average for brain-computer interface 被引量:1
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作者 Jin’an GUAN Yaguang CHEN 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2008年第2期194-197,共4页
Communication signals should be estimated by a single trial in a brain-computer interface.Since the relativity of visual evoked potentials from different sites should be stronger than those of the spontaneous electro-... Communication signals should be estimated by a single trial in a brain-computer interface.Since the relativity of visual evoked potentials from different sites should be stronger than those of the spontaneous electro-encephalogram(EEG),this paper adopted the time-lock averaged signals from multi-channels as features.200 trials of EEG recordings evoked by target or non-target stimuli were classified by the support vector machine(SVM).Results show that a classification accuracy of higher than 97%can be obtained by merely using the 250–550 ms time section of the averaged signals with channel Cz and Pz as features.It suggests that a possible approach to boost communication speed and simplify the designation of the brain-computer interface(BCI)system is worthy of an attempt in this way. 展开更多
关键词 in-phase average visual evoked potentials brain-computer interfaces single-trial estimation
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Broadband ADCP digital signal processing based on CIC filter banks 被引量:2
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作者 YAN Yu CHEN Shi-li ZENG Zhou-mo 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第2期116-125,共10页
The acoustic Doppler current profilers(ADCP)as a new type of flow measuring equipment,can measure the flow velocity of the channel section directly.ADCP has the advantages of short measuring time and wide measuring ra... The acoustic Doppler current profilers(ADCP)as a new type of flow measuring equipment,can measure the flow velocity of the channel section directly.ADCP has the advantages of short measuring time and wide measuring range.The traditional ADCP processing system uses analog method to realize demodulation and filtering,which will introduce extra errors.While digital processing system will greatly increase the computation and slow down the speed of data processing.To solve this problem,an efficient real-time broadband ADCP digital signal processing system is proposed based on the low computational cascade integrator comb(CIC)cascade and interpolated second-order polynomial(ISOP)filter banks.The digital in-phase and quadrature(IQ)demodulation,CIC filter banks,and complex autocorrelation operation steps are cascaded with a pipelined method in the system,which greatly improves the system operating speed while avoiding the high memory occupation of non-real-time systems. 展开更多
关键词 acoustic Doppler current profilers(ADCP) in-phase and quadrature(IQ)demodulation cascade integrator comb(CIC) interpolated second-order polynomial(ISOP) autocorrelation operation
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Optimization of Mapping Rule of Bit-Interleaved Turbo Coded Modulation with 16QAM 被引量:1
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作者 费泽松 杨宇 +1 位作者 刘林南 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期18-21,共4页
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor... Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation. 展开更多
关键词 binary Turbo coded modulation quadrature amplitude modulation (QAM) mapping rule in-phase and quadrature (I-Q) coded modulation
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Conversion of out-of-phase to in-phase order in coupled laser arrays with second harmonics 被引量:1
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作者 Chene Tradonsky Micha Nixon +4 位作者 Eitan Ronen Vishwa Pal Ronen Chriki Asher A.Friesem Nir Davidson 《Photonics Research》 SCIE EI 2015年第3期77-81,共5页
A novel method for converting an array of out-of-phase lasers into one of in-phase lasers that can be tightly focused is presented.The method exploits second-harmonic generation and can be adapted for different laser ... A novel method for converting an array of out-of-phase lasers into one of in-phase lasers that can be tightly focused is presented.The method exploits second-harmonic generation and can be adapted for different laser arrays geometries.Experimental and calculated results,presented for negatively coupled lasers formed in a square,honeycomb,and triangular geometries are in good agreement. 展开更多
关键词 Conversion of out-of-phase to in-phase order in coupled laser arrays with second harmonics
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EFFECTS OF STRAIN RATIO ON THERMAL-MECHANICAL CYCLIC STRESS-STRAIN RESPONSE AND FATIGUE LIFE IN DS SUPERALLOY DZ125
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作者 G.D.Zhang S.L.Liu +1 位作者 Y.H.He R.Z.Chen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第4期528-533,共6页
The effects of strain ratio on thermal-mechanical cyclic stress-strain response and fatigue life in DS superalloy DZ125 have been studied by performing tests at various strain ratio experiments, under strain-controlle... The effects of strain ratio on thermal-mechanical cyclic stress-strain response and fatigue life in DS superalloy DZ125 have been studied by performing tests at various strain ratio experiments, under strain-controlled and temperature cycling from 550 to 1000℃. It is shown that thermal-mechanical cyclic stress-strain response behavior not only depend on magnitude of strain, and temperature-loading phase angle, but also strain ratio. Fatigue life at strain ratio Rε=-0.3 is longer than that of strain ratio Rε=-1.0, under in-phase thermal-mechanical loading. However, Fatigue life at strain ratio Rε=-0.3 is shorter than that of strain ratio Rε=-1.0, under out-of-phase thermal-mechanical loading. The thermal-mechanical fatigue (TMF) damage model was discussed. Results of fractography show that fatigue, creep and oxidation damage always occur during TMF. The main damage mode depends on loading wave, strain ratio and magnitude of strain. 展开更多
关键词 thermal-mechanical fatigue in-phase out-of-phase
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In—Phase Resonances with Generic Transmission Zeros and Eigenvectors of Hamiltonian in Models of Single Channel Transport
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作者 CHENTao XIONGShi-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第1期121-124,共4页
We investigate the phase coherent transport in a single channel system. The theory that the transmission zeros lead to abrupt phase change and in-phase resonances is confirmed numerically in two tight-binding models. ... We investigate the phase coherent transport in a single channel system. The theory that the transmission zeros lead to abrupt phase change and in-phase resonances is confirmed numerically in two tight-binding models. After calculating the eigenvalues and eigenvectors of the Hamiltonians we also confirmed that the same symmetry of the eigenvectors also leads to the abrupt phase change and in-phase resonances that equal the transmission zero. 展开更多
关键词 quantum dot phase coherent transport in-phase resonance
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Hepatic steatosis with mass effect:A case report
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作者 Na Hu Shi-Jun Su +5 位作者 Jin-Ye Li Hui Zhao Shan-Feng Liu Lin-Sheng Wang Ruo-Zhen Gong Chuan-Ting Li 《World Journal of Clinical Cases》 SCIE 2022年第30期11066-11073,共8页
BACKGROUND Hepatic steatosis is a common radiologic finding.Some imaging inklings are the absence of a mass effect,and there is currently no report of hepatic steatosis with mass effect.CASE SUMMARY A 23-year-old fema... BACKGROUND Hepatic steatosis is a common radiologic finding.Some imaging inklings are the absence of a mass effect,and there is currently no report of hepatic steatosis with mass effect.CASE SUMMARY A 23-year-old female was admitted due to a liver mass for half a month.No obvious abnormalities were found in physical and laboratory examinations.Ultrasound,computed tomography,and magnetic resonance imaging showed a huge mass between the liver and stomach with a significant mass effect,and the caudate lobe and left lobe of the liver were involved.The signal on T2-and T1-weighted fat-saturated images of the mass was significantly reduced,and the enhanced scan showed inhomogeneous enhancement.Surgical and pathological findings indicated the diagnosis of hepatic steatosis.The operation and re-review of the patient’s images showed that the lesion was supplied by the branch of the hepatic artery.The signal on T1-weighted out-of-phase images of the lesion was lower than on in-phase images,and there was no black rim cancellation artifact around the hepatic steatosis area on T1-weighted out-of-phase images.The dynamic enhancement pattern of the lesion was similar to that of the adjacent normal liver parenchyma.The above characteristics suggested that the lesion was hepatic steatosis.However,in this case,the lesion showed exogenous growth and was mass-like,with an obvious mass effect,which has not been reported previously.CONCLUSION Hepatic steatosis could grow exogenously and has an obvious mass effect.It needs to be distinguished from fat-rich tumors.The T1-weighted in-and out-of-phase images and dynamic enhanced scanning are valuable for differential diagnosis of this lesion. 展开更多
关键词 Hepatic steatosis Computed tomography Magnetic resonance imaging in-phase and out-of-phase imaging Case report
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Bafang Fabric Keep up the World Demin in-phase
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《纺织服装周刊》 2008年第44期4-4,共1页
From Shanghai to Haining Bafang Weaving Co., Ltd., through China’s busiest high way, we saw the adverts of Bafang Fabric on the side of the road. Upon the arriving in the downtown of Haining, the huge advert of Bafan... From Shanghai to Haining Bafang Weaving Co., Ltd., through China’s busiest high way, we saw the adverts of Bafang Fabric on the side of the road. Upon the arriving in the downtown of Haining, the huge advert of Bafang Fabric attracts your eye --"advertising plus advertising to increase strength, that is, quality, and brand ". 展开更多
关键词 World Bafang Fabric Keep up the World Demin in-phase
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