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GPS/SPL组合伪距测量的精度因子仿真研究

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系统仿真学报 2008年第18期20卷 4975-4977,4981页

作者：甘兴利袁赣南哈尔滨工程大学自动化学院

针对舰载飞机在降落过程中对高精度和高稳定性导航系统的需求,提出了一种舰载伪卫星(SPL)增强GPS导航的技术方案。通过和机载伪卫星方案的对比,分析舰载伪卫星的优越性和可行性。证明了增加舰载伪卫星可以减小几何精度因子GDOP值和降低... 详细信息

针对舰载飞机在降落过程中对高精度和高稳定性导航系统的需求,提出了一种舰载伪卫星(SPL)增强GPS导航的技术方案。通过和机载伪卫星方案的对比,分析舰载伪卫星的优越性和可行性。证明了增加舰载伪卫星可以减小几何精度因子GDOP值和降低用户接收机选星的难度,把选星方法由计算四颗GPS卫星的投影四面体体积最大,简化为计算三颗GPS星的投影三角形面积最大。并通过Matlab仿真定量地分析了增强前后的伪距测量的各种精度因子的变化趋势,在GPS高度角在10o和70o之间和伪卫星的高度角在-10o和-90o之间时,GPS/SPL组合导航系统具有最优性能。

关键词： GPS 伪卫星精度因子伪距测量

Well-Posedness of Initial Boundary Value ProblemsAssociated with Absorbing Boundary Conditions

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Systems Science and Systems Engineering 1999年第1期9卷 96-100页

作者： WEI Suhua(Department of APPlied Geophysics, china Univelsity of Geoscience, Beijing, 100083, china)Zhang Gang(Department of Mathematics, {{2. Colleage of Education, {{2., china)

In this paper we get one-way wave equations by using pseudo-differential operator theory,and present a set of absorbing boundary conditions based on the higher order aPProximations of oneway wave equations. An integral identity is the key point of the approximation. Also, we have provedthe well-posedness of the initial boundary value Problems related to our absorbing boundary conditionsconstructed in this artical.

关键词： one-way wave equation well-posedness absorbing boundary condition initial boundaryvalue problem

Fluvastatin inhibits activation of JAK and STAT proteins in diabetic rat glomeruli and mesangial cells under high glucose conditions

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Acta Pharmacologica Sinica 2007年第12期28卷 1938-1946页

作者： Yong-hong SHI~2.Song ZHAO~2.Chen WANG~2.Ying LI~3,Hui-jun DUAN~(2.4)~2.Department of Pathology,Hebei Medical University,shijiazhuang 050017 ~3 Institute of Nephrology,Third Hospital,Hebei Medical University,shijiazhuang 050051,{2. Department of Pathology Hebei Medical UniversityShijiazhuang 050017

Aim:The aim of the present study was to further elucidate the mechanism of theprotective role of fluvastatin on diabetic ***:Streptozotocin-induced diabetic rats were treated daily with fluvastatin (4 mg/kg body weight) *** animals were killed 4 weeks later and urine and blood samples *** kidney tissues were removed and subjected to the *** glomerular mesangial cells (GMC) were cultured under normalglucose (5.5 mmol/L),high glucose (HG,30 mmol/L),HG+AG490 (10 μmol/L),orHG with fluvastatin (1 μmol/L).Glomeruli or the GMC lysate was immunoprecipi-tared and/or immunoblotted with antibodies against Janus kinase 2.(JAK2.,SH2.domain containing tyrosine phosphatase-1 (SHP-1),phosphospecific SHP-2.andsignal transducer and activators of transcription (STAT),***-forming growth factor-β(TGF-β1) mRNA was measured by *** proteinsynthesis of TGF-β1 and fibronectin in the culture medium of GMC was detectedby ***:The phosphorylation levels of JAK2.STAT1,STAT3,andSHP-2.increased significantly,and SHP-1 phosphorylation was reduced in glom-eruli of diabetic *** with fluvastatin reduced phosphorylation levelsof JAK2.STAT1,STAT3,and SHP-2.in glomeruli of diabetic rats,but it had noeffect on the dephosphorylation of *** exposure of GMC to 30 mmol/Lglucose caused the activation of JAK2.STAT1,STAT3,and *** upregulatedTGF-β1 expression and increased protein synthesis of *** highglucose-induced changes were suppressed by fluvastatin,as well as AG490,aJAK2.***:The regulation of the phosphorylation of JAK/STATby fluvastatin may be responsible for its renal protective effects on diabeticnephropathy.

关键词： fluvastatin diabetic nephropathy Janus kinase signal transducer and activators of transcription

Effects of Intranigral Injection of Glutamate/GABA on Iron Metabolism in the Nigrostriatum of Rats

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Effects of Intranigral Injection of Glutamate/GABA on Iron M...

Longitudinal waves in one dimensional non-uniform waveguides

第九次全国暨2.07海内外生物膜学术研讨会

作者： Peng Guan~(1 2. Xiang-Lin Duan~(1 2. Na Wang~(1 2. Yan-Zhong Chang~(1 2. 1 The Institute of Molecular Neurobiology and Neuropharmacology Hebei Normal University shijiazhuang 050016 Hebei Province china 2.The key labortry of Animal Physiology Biochemistry and Molecular Biology of Hebei Province Hebei Normal University shijiazhuang 050016 Hebei Province china

＜正＞To investigate the effects of intranigral increased glutamate/GABA on iron metabolism in the nigrostriatum of rats,Glutamate Mono-Sodium（GMS）and GABA was respectively stereotaxically injected into substantia n... 详细信息

关键词： Glutamate GABA DMTI(-IRE) Hephaestin

来源： cnki会议评论

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Theoretical & Applied Mechanics Letters 2011年第2期1卷 33-36页

作者： Shuqi Guo,~(1,a) Zhi Zhang,~2.and Shaopu Yang~3 1)Department of Mechanics,shijiazhuang Tiedao University,shijiazhuang 050043,{2.. 2.School of Civil Engineering,shijiazhuang Tiedao University,shijiazhuang 050043,{2. 3)School of Mechanical Engineering,shijiazhuang Tiedao University,shijiazhuang 050043,{2. School of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang 050043 China

Wave approach is used to analyze the longitudinal wave motion in one dimensional non-uniform *** assumptions of constant wave velocity and no wave conversion,there exist four types of non-uniform rods and corresponding traveling wave solutions are *** obtained results indicate that the kinetic energy is preserved as a constant and the wave amplitude is inversely proportional to square root of the cross-sectional area of the *** certain condition,there exists a cut-off frequency for the rod with variation in geometric or material properties,below which waves do not propagate along the non-uniform *** the rod with arbitrary variable cross-section, the conclusions are similar if the wave frequency is high *** a series solution of the wave motion is presented.

关键词： longitudinal wave traveling solution cut-off frequency non-uniform rod

An Optimization Method of Selecting Parameters in Building Fuzzy Decision Trees and the Application in Customer Forfeit Crisis

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International Journal of Systems and Control

International Journal of Systems and Control 2007年第2期 118-126页

作者： Zhao Minghua, Chen Yuzhe, Dong Dong College of Mathematics and Information Science,Hebei Normal University shijiazhuang, Hebei, 050016, {{2.

Compared with conventional decision tree (CDT), fuzzy decision tree (FDT) inductive learning algorithms are more powerful and practical to handle with ambiguities in classification problems. A parameter, named significant level (SL)α , plays an important role in the entire process of building FDTs. however this parameter is usually estimated based on users by domain knowledge, personal experience or requirements, which is hard to build a high performance FDT. This paper aims at developing a method to determine an optimal SL value through analysing the relationship between the fuzzy entropy andα . On the basis of pointing out the advantage of FDT in solving fuzziness of customer data compared with CDT, the method is applied to analyse the customer forfeit crisis for rising competition ability of enterprises. Experiment is made to prove that FDT, built by the optimal SL, can lead to better classification performance.

关键词： inductive learning fuzzy decision tree parameterα customer forfeit crisis

Research　on　Classification　of　Development　Level　in　china＇s　Postal　Communication

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The Journal of china Universities of Posts and Telecommunications 1996年第2期3卷 58-61页

作者： Wang Weimin(shijiazhuang Postal College, shijiazhuang 0500{2., P. R. {{2.) shijiazhuang Postal College Shijiazhuang 050021 P. R. China

in this poper the unbalance of development level in china's postal communication is discussed,classified into four types by Cluster Analysis Method, and the suggestion on postal service and postal network based on the... 详细信息

关键词： s: cluster analysis classification postal service development construction of postal network

Surface geometry and magnetism of Eu@C60 monolayer on Ag（111）

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Science china(Physics,Mechanics & Astronomy) 2012年第9期Mechanics & Astronomy) .卷 1589-1593页

作者： ZHAO ZhiWei 1,2.WANG Jing 1,2.& LIU Ying 1,2.1 Department of Physics,Hebei Normal University,and Hebei Advanced Thin Film Laboratory,shijiazhuang 050016,china 2.National Key Laboratory for Materials Simulation and Design,Beijing 100083,china

The surface geometry,electronic structure,and magnetism of Eu@C 60 monolayer absorbed on Ag(111) have been investigated within the framework of density functional *** Eu@C 60 monolayer has been constructed on Ag(111) substrate by one of the hexagon faces of C 60 downward and its mirror plane face parallel to Ag(111).The Eu@C 60 monolayer induces a reconstruction of the Ag(111) substrate and the perpendicular distance between the Eu@C 60 and Ag(111) surface is 2.06,being shorter than that between C 60 and Ag(111) surface by *** is no chemical bond formed between the Eu@C 60 and Ag(111),and only 0.55e transferred from Ag(111) to Eu@C 60.A large magnetic moment about 6.80 B per unit cell is found for Eu@C 60 /Ag(111) system.

关键词： endohedral fullerene two-dimensional C 60 domain magnetic organic molecule

Phase transformation refinement of coarse primary carbides in M2.high speed steel

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Progress in Natural Science:Materials International 2011年第2期21卷 180-186页

作者： Fu-sheng PAN~(1,2.,Wei-qing WANG~1,Ai-tao TANG~1,Li-zhi WU~3,Ting-ting LIU~1,Ren-ju CHENG~1 1.College of Materials Science and Engineering,Chongqing University,Chongqing 400030,china 2.Chongqing Academy of Science and Technology,Chongqing 40112.,china 3.Quality Department,Heye Science and Technology Co.,Ltd.,{2. 050031,china [a] College of Materials Science and Engineering Chongqing University Chongqing 400030 China [b] Chongqing Academy of Science and Technology Chongqing 401123 China [c] Quality Department Heye Science and Technology Co. Ltd. Shijiazhuang 050031 China

The decomposition of the coarse primary M2. carbide in M2.high speed steel was investigated by using optical microscope,scanning electron microscope,energy dispersive spectrometer and X-ray diffraction *** is indicated that the SEM observation using deeply etched samples can clearly reveal the details of the decomposition products of primary M2. eutectic *** MC is granular and M6C is peanut-shaped in the decomposition products,and the decomposition products are found to be very small in the *** the increase of annealing temperature and duration,part of the peanut-shaped M6C carbides change to simple skeleton-shaped *** phase transformation refinement of primary M2. carbides in M2.steel by the decomposition of metastable M2. carbides at high temperature can be obtained if suitable annealing parameters are *** complete decomposition of M2. to M6C and MC will occur when（1 100℃,4 h） or（1150℃,2.h） annealing treatment is employed in M2.high speed steel.

关键词： high speed steel carbides decomposition phase transformation refinement morphology