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Unitary cyclic ESPRIT-like direction finding

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Science China(Information Sciences) 2010年第10期53卷 2087-2096页

作者： LIU ZhiGang & WANG JinKuan Department of Electronic Information, Northeastern University, qinhuangdao 066004, China 1. Department of Electronic Information Northeastern University Qinhuangdao 066004 China

A unitary formulation of cyclic ESPRIT algorithm, with uniform linear array (ULA) configuration, is proposed by constructing the forward backward cyclic autocorrelation matrix by Hermitian mapping. This approach not only substantially reduces the computational complexity via real-valued decomposition, but also outperforms the forward backward spatial smoothing algorithm for uncorrelated or correlated sources. In addition, this method allows to select desired signals and to ignore interferences because of its signal-selective property. The performance analysis shows that for uncorrelated or correlated sources, the Hermitian mapping approach has a lower RMSE and a higher output SNR than the FBSS method. Finally, simulation results show the effectiveness of the proposed methods.

关键词： array signal processing cyclostationary signals direction of arrival cyclic ESPRIT unitary ESPRIT

Improvement　of　K_(IC)　and　ΔK_(th)　for　Steel　GCr15　by　SL　Technology

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Journal of Iron and Steel Research International 1997年第1期4卷 42-45页

作者： Yang YulinYanshan University, qinhuangdao (066004), China, Huang QingHarbin Heavy Machinery Factory, Harbin (150014), China Yanshan Univ Qinhuangdao 006004 Peoples R China Harbin Heavy Machinery Factory Harbin 150014 Peoples R China

The inclusion of steel GCr15 using SL and CAB technologies has been investigated and determined with SEM and optical microscope. The K IC and Δ K th of steel GCr15 were measured with the method of fracture mechanics. Experimental results show that the volume fraction of inclusion and the large particle inclusion can be reduced by using SL technology. Both values of K IC and Δ K th with SL technology were higher than those with CAB technology to some extent. It is feasible to measure Δ K th of steel GCr15 with lift drop method for multiple specimens.

关键词： ladle injection bearing steel fracture toughness

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Effect of Pre-treatment on the Bi-2223/Ag Tapes Fabricated with Different Powders

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稀有金属材料与工程 2011年第S3期40卷 325-328页

作者： Li Mingya1, Chen Xingpin2, Ye Chengli1, Yu Liang1, Zhu Xu1 1 Northeastern University at qinhuangdao, qinhuangdao 066004, China 2 Chongqing University, Chongqing 400044, China NE Univ qinhuangdao Dept Mat Sci & Engn Qinhuangdao 066004 Peoples R China Chongqing Univ Chongqing 400044 Peoples R China

Samples of Bi-2223/Ag tapes fabricated with powders contained different lead oxide compounds were annealed at a temperature lower than the formation temperature of Bi-2223 phase before traditional heat treatment, which was called pretreatment. In pre-treatment stage, samples were heat treated at 780 ℃ in 8.5% O2, and the dwelling time is different. Experimental results show that pre-treatment had different influence on the formation and size of the Bi-2223 grains for tapes fabricated with powders contained different lead oxide compounds. For tapes contained both Ca2PbO4 and the 3321 phase, the decomposition of the 3321 phase enhanced the growth of Bi-2212 grains during pre-treatment process, which promoted the formation of Bi-2223 phase and enhanced the superconducting properties of Bi-2223/Ag tapes.

关键词： pre-treatment Bi-2223/Ag tapes lead oxide compounds critical current

NOVEL 6-SPS PARALLEL 3-DIMENSIONAL PLATFORM MANIPULATOR AND ITS FORCE/MOTION TRANSMISSION ANALYSIS

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Chinese Journal of Mechanical Engineering 2002年第4期15卷 298-302页

作者： Jin Zhenlin School of Mechanical Engineering, Yanshan University, qinhuangdao 066004, ChinaGao Feng Hebei University of Technology School of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei University of Technology

The unique design for a novel 6-SPS parallel 3-dimensional platformmanipulator with an orthogonal configuration is investigated. The layout feature of the parallelmanipulator is described. Its force/motion transmission capability, evaluation criteria arepresented. At the orthogonal configuration, the criteria and the relationships between the criteriaand the link lengths are analyzed, which is important since it can provide designer a piece ofvaluable information about how to choose the linear actuators. From the analysis of the results itis shown that the force/motion transmission capabilities of the parallel manipulator arecharacterized by isotropy at the orthogonal configuration. The manipulator is particularly suitablefor certain applications in 6-DOF micromanipulators and 6-axis force/moment transducers.

关键词： 6-SPS parallel manipulator 3-dimensional platform manipulator isotropy

Design of sequence set with group-wise zero correlation window

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 39-41页

作者： WANG Yang-zhi XU Cheng-qian College of Information Science and Engineering,Yanshan University,qinhuangdao 066004,China [a]College of Information Science and Engineering Yanshan University qinhuangdao 066004 China

Zero correlation window （ZCW） or zero correlation zone （ZCZ） sequence can be used in quasi-synchronous code division multiple access （QS-CDMA） system to eliminate multiple access and multipath interferences. However, as the length of ZCW or ZCZ increases, fewer sequences are available. Recently, a new concept, sequence set with group-wise zero correlation window is introduced, which can increase the number of available sequences for a QS-CDMA system. In this article, a new method for generating sequence set with group-wise zero correlation window is presented. This method is based on a Hadamard matrix of size N×N and a pair of Hadamard matrices of size M×M. Compared with previous methods, the proposed sequence set has a group-wise zero correlation window for both periodic and aperiodic cross-correlation functions.

关键词： ZCW group-wise zero correlation window multiuser detection Hadamard matrix

BIOTECHNOLOGY AND ITS FUTURE

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Journal of Northeast Forestry University 1993年第1期4卷 31-35页

作者： Guo Chengliang Xu Sheng Yu Sun qinhuangdao Animal and Plant Quarantine Bureau 1. qinhuangdao Animal and Plant Quarantine Bureau China

WHAT IS BIOTECHNOLOGYIn the earlier time,biotechnologymainly meant microbiologic *** 1970‘s,as gene engineering,cytolog-ical engineering and enzyme technologydeveloped,the technology of using organ-ism functions became the basic intension *** can be de-fined as an area of applied bioscience andtechnology,which is based on the theoriesof biology(microbiology,genetics,biochemistry,cytology,molecular biology),

关键词： Biotechnology biochemistry biotechnology cytology genetics earlier meant microorganism 林业研究 frontier

Solution of a hollow thick-wall cylinder subject to quadric function pressures and its limit when l→∞

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Science China(Technological Sciences) 2004年第2期47卷 229-236页

作者： LIU Zhubai1,SHAN Rui2,LIU Wen2 & NI Liyong1 1.College of Mechanical Engineering,Yanshan University,qinhuangdao 066004,China 2.College of Science,Yanshan University,qinhuangdao 066004,China 1. College of Mechanical Engineering Yanshan University 066004 Qinhuangdao China 2. College of Science Yanshan University 066004 Qinhuangdao China

The problem of a hollow thick-wall cylinder subject to quadric function pressures is solved with a new stress function, thus laying the basis for solving the spatial symmetric deformation of a hollow cylinder subject ... 详细信息

关键词： quadric function pressure, analytic solution, stress function, hollow cylinder.

Synthesis of Self-assembled Mesoporous Zirconia with Rheological Phase Reaction

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稀有金属材料与工程 2011年第S3期40卷 263-265页

作者： Wang Xiaoqiang1, Xia Wang1, Lu Baoqiang1, Zhen Congmian2 1Northeastern University at qinhuangdao Branch, qinhuangdao 066004, China 2Hebei Normal University, Shijiazhuang 050016, China Northeastern Univ Dept Mat Sci & Engn Qinhuangdao Branch Qinhuangdao 066004 Peoples R China Hebei Normal Univ Shijiazhuang 050016 Peoples R China

The rheological phase reaction method was used to obtain the zirconia spherical particles with monodispersity and single-scale. And based on this, we got the colloidal dispersion of Zirconia (ZrO2). Mesoporous zirconia were successfully synthesized by vacuum filtration or gravitational deposition as assembly methods using monodispersed PMMA as template. The precursor was studied by FT-IR, TG and DTA, these results further revealed that the precursor is ZrO(C6H5COO)2·2H2O. By the phase analysis in the XRD patterns it was proved that the ZrO2 crystallites have monoclinic phase structure. SEM results indicated that the aperture size is from 50-500 nm and increases with the process conditions changing, moreover, the sample has good thermal stability. This study shows the controllability of ZrO2 macroporous materials’ aperture size was realized at some extent.

关键词： ZrO2 mesoporous rheological phase reaction self-assemble

Degradation of acid fuchsine by a modified electro-Fenton system with magnetic stirring as oxygen supplying

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Journal of Environmental Sciences 2010年第4期22卷 547-554页

作者： Yiping Sheng,Limin Zhen,Xiuli Wang,Ning Li,Qi Tong College of Environmental and Chemical Engineering,Yanshan University,qinhuangdao,Hebei 066004,China. [a] College of Environmental Chemical Engineering Yanshan University Qinhuangdao Hebei 066004 China

The current modified electro-Fenton system was designed to develop a more convenient and efficient undivided system for practical wastewater treatment. The system adopted a cathode portion that employed magnetic stirring instead of common oxygen gas diffusion or gas sparging to supply oxygen gas for the electrolyte solution. Key factors influencing the cathode fabrication and activit） were investigated. The degradation of acid fuchsine with a self-made graphite-polytetrafluorethylene cathode was studied using spectrophotometer. It was found that the cathode generated hydrogen peroxide with high current efficiency and the hydrogen peroxide yield of the cathode did not decay after 10 times reuse. With the Pt anode at a ferrous ion concentration of 0.5 mmol/L, a pH of 3, and using magnetic stirring, dye decolorization could be rapidly accomplished but the destruction of benzene rings and intermediates was fairly difficult. With a Fe anode, dye degradation was more complete.

关键词： electro-Fenton system oxygen gas magnetic stirring acid fuchsine degradation