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Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

Fast PARAFAC decomposition with application to polarization sensitive array parameter estimations

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Journal of Systems Engineering and electronics 2018年第4期29卷 714-722页

作者： LI Yang The 10th research institute China Electronics Technology Group Corporation

In tensor theory, the parallel factorization （PARAFAC）decomposition expresses a tensor as the sum of a set of rank-1tensors. By carrying out this numerical decomposition, mixedsources can be separated or unknown system parameters can beidentified, which is the so-called blind source separation or blindidentification. In this paper we propose a numerical PARAFACdecomposition algorithm. Compared to traditional algorithms, wespeed up the decomposition in several aspects, i.e., search di-rection by extrapolation, suboptimal step size by Gauss-Newtonapproximation, and linear search by n steps. The algorithm is ap-plied to polarization sensitive array parameter estimation to showits usefulness. Simulations verify the correctness and performanceof the proposed numerical techniques.

关键词： tensor decomposition parallel factorization(PARAFAC) alternating least squares (ALS) polarization sensi-tive array (PSA)

Growth of CdS crystals by the physical vapor transport method

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Journal of Semiconductors 2009年第10期30卷 17-20页

作者：程红娟徐永宽杨巍于祥潞严如岳赖占平 china electronics technology group corporation No.46 Research Institute

Based on the physical vapor transport （PVT） method, the growth of large-size CdS crystals inside a vertical semi-closed tube is studied. Firstly, in order to ensure 1D diffusion-advection transport, multi-thin tubes are used in the growth tube. The XRD spectra of the CdS crystal grown in this configuration indicates that the crystal quality has clearly been improved, where the FWHM is 58.5 arcsec. Secondly, theoretical and experimental growth rates under different total pressures are compared; the results show that the experiential growth rate equation is valid for our semi-tube growth, and it could be used to estimate the growth rate and maximum growth time under different total pressures.

关键词： CdS growth rate growth surface the saturated vapor pressure

Genetic-optimization framework for SVC transmission based on partial cooperative communication

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Journal of Systems Engineering and electronics 2017年第5期28卷 861-870页

作者： Kai Zhao Yongcheng Sun The 28th research institute of china electronics technology group corporation

A genetic-optimization framework based on the partial cooperation communication protocol is proposed for scalable video coding (SVC) stream transmission under multi-relay amplify and forward cooperative networks. Unlike traditional cooperative transmission schemes, the transmission mode for each coded unit in this new protocol can be switched flexibly between direct transmission and cooperative transmission. Obviously, under this protocol, the bandwidth efficiency and transmission robustness can be balanced adaptively according to the priority level of coded units and wireless channel fading characteristics. Based on this, a well-known genetic optimization algorithm-differential evolution is exploited here to find the jointly optimal transmission modes, power allocation and unequal error protection (UEP) channel coding strategies to minimize the end to end reconstructed video distortion. Extensive simulation results show that, compared with classical optimal cooperative UEP transmission schemes, the proposed optimized transmission framework based on the partial cooperative protocol can bring significant peak-signal-to-noise-ratio (PSNR) gains for the reconstructed video in a variety of channel bandwidth, power budget and test sequences.

关键词： scalable video coding partial cooperative communication unequal error protection source-relay power allocation differential evolution

Microstructure and properties of aging Cu–Cr–Zr alloy

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Rare Metals 2014年第2期33卷 134-138页

作者： Kun Wang Ke-Fu Liu Jing-Bo Zhang institute of Electric Lighting Source Fudan University No.23 research institute China Electronics Technology Group Corporation No. 23 research institute China Electronics Technology Group Corporation

The crystallography and morphology of precipitate particles in a Cu matrix were studied using an aged Cu–Cr–Zr alloy by transmission electron microscopy（TEM） and high-resolution transmission electron microscopy（HRTEM）. The tensile strength and electrical conductivity of this alloy after various aging processes were tested. The results show that two kinds of crystallographic structure associated with chromium-rich phases, fcc and bcc structure, exist in the peak-aging of the alloy. The orientation relationship between bcc Cr precipitate and the matrix exhibits Nishiyama–Wasserman orientation relationship. Two kinds of Zr-rich phases（Cu4Zr and Cu5Zr）can be identified and the habit plane is parallel to {111}Cu plane during the aging. The increase in strength is ascribed to the precipitation of Cr- and Zr-rich phase.

关键词： Cu–Cr–Zr alloy Aging process Crystallography Morphology Strengthening mechanism

SOI-based radial-contour-mode micromechanical disk resonator

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Journal of Semiconductors 2011年第11期32卷 72-76页

作者：贾英茜赵正平杨拥军胡晓东李倩 School of Information Engineering Hebei University of Technology The 13th research institute China Electronics Technology Group Corporation china electronics technology group corporation

This paper reports a radial-contour-mode micromechanical disk resonator for radio frequency applications. This disk resonator with a gold plated layer as the electrodes, was prepared on a silicon-on-insulator wafer, which is supported by an anchor on another silicon wafer through Au-Au thermo-compression bonding. The gap between the disk and the surrounding gold electrodes is 100 nm. The radius of the disk is 20μm and the thickness is 4.5 μm. In results, the resonator shows a resonant frequency of 143 MHz and a quality factor of 5600 in vacuum

关键词： RF-MEMS micromechanical disk resonator SOI, thermo-compression bonding

M-FCN based sea-surface weak target detection

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Journal of Systems Engineering and electronics 2021年第5期32卷 1111-1118页

作者： PAN Meiyan SUN Jun YANG Yuhao LI Dasheng YU Junpeng The 14th research institute of china electronics technology group corporation Nanjing 210039China Key Laboratory of IntelliSense technology China Electronics Technology Group CorporationNanjing 210039China

This paper focuses on the sea-surface weak target detection based on memory-fully convolutional network(M-FCN)in strong sea ***,the constant false alarm rate(CFAR)detection method utilizes a low threshold with high probability of false alarm to detect sea-surface weak targets after non-coherent *** the detection threshold can generate a large number of false alarms while increasing the detection rate,and how to suppress a large number of false alarms is the key to improve the performance of weak target ***,the detection result of the low threshold is operated to construct the target matrix suitable for the size of fully convolutional networks and the convolution operator ***,the M-FCN architecture is designed to learn the different accumulation characteristics of the target and the sea clutter between different *** improving the detection performance,the historical multi-frame information is memorized by the network,and the end-to-end structure is established to detect sea-surface weak target *** results on measured data demonstrate that the M-FCN method outperforms the traditional track before detection(TBD)method and reduces false alarm tracks by 35.1%,which greatly improves the track quality.

关键词： sea-surface weak target detection memory-fully convolutional network(M-FCN) multi-frame information end-to-end

A CDR System Based on Improved Second Order Digital Filter, Hysteretic Voter and Phase Interpolator

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Chinese Journal of electronics 2019年第6期28卷 1227-1233页

作者： ZHAO Yuyue JIANG Yingdan YANG Yu SHEN Guangzhen HU kai YAN Hua East Technologies Incorporated china electronics technology group corporation No.58 research institute

The proposed Clock and data recovery system(CDRS) has three improved parts. The second order digital filter with rounding algorithm implements fractional gain and avoids direct current quantization noise which varies between –q/2 and +q/2 while that of traditional filter varies between 0 and +q(q is quantization step). The hysteresis majority voter can combat high frequency and strong jitter especially in quasi-steady state. The improved Phase interpolator(PI) has much smaller current-switching glitch and phase glitch since the weighting current changes gradually instead of *** optimized CDRS can handle up to ±6000 ppm(parts per million) frequency offset and the phase resolution is ■/LSB(Least significant bit) according to analysis. The simulations of jitter transfer function and jitter tolerance by Matlab, simulations of phase noise by spectre using Verilog+Verilo A model, and measurements of frequency offset and jitter tolerance all show its good performance.

关键词： CDRS Bang-bang phase detector(!!PD) Hysteretic voter Second order digital filter Phase interpolator Jitter transfer Jitter tolerance

Wideband CMOS variable gain amplifier with decibel-linear gain control characteristic

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The Journal of china Universities of Posts and Telecommunications 2019年第1期26卷 59-64页

作者： Dun Shubo Li Bin Shi Guochao Yang Geliang The 54th research institute of china electronics technology group corporation

This paper presents a wideband variable gain amplifier(VGA) featuring a decibel-linear gain control characteristic. The decibel-linear gain control function is realized using two VGA cells and a control signal converter. The bandwidth is extended by using cascode architecture together with active inductive load. To achieve small parasitic and low area,direct current(DC) coupling is adopted in the circuit while a DC offset cancellation(DCOC) circuit is introduced to cancel the DC offset. Fabricated in a 0.18 μm complementary metal oxide semiconductor(CMOS) process, the chip occupies an area of 0.53 mm×0.48 mm(including pads) and draws a total current of 9 mA from a 1.8 V supply. The measurement results show that the gain of the VGA varies from-40 dB to 18 dB while the control voltage varies from 0 to 1.8 V, resulting in a total gain control range of 58 dB. The 3 dB bandwidth of the VGA is larger than 260 MHz at maximum gain.

关键词： variable gain amplifier exponential gain control DC offset cancellation wideband