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A time-driven transmission method for well logging networks

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Petroleum Science 2009年第3期6卷 239-245页

作者： Wu Ruiqing Chen Wei Chen Tianqi Li Qun School of Electronic Engineering University of Electronic Science and Technology of China Sichuan 610054 China Research ＆ Technical Center China Oilfield Services Limited EO. 232 Beijing 101149 China

Long delays and poor real-time transmission are disadvantageous to well logging networks consisting of multiple subnets. In this paper, we proposed a time-driven transmission method （TDTM） to improve the efficiency and precision of logging networks. Using TDTM, we obtained well logging curves by fusing the depth acquired on the surface, and the data acquired in downhole instruments based on the synchronization timestamp. For the TDTM, the precision of time synchronization and the data fusion algorithm were two main factors influencing system errors. A piecewise fractal interpolation was proposed to fast fuse data in each interval of the logging curves. Intervals with similar characteristics in curves were extracted based on the change in the histogram of the interval. The TDTM is evaluated with a sonic curve, as an example. Experimental results showed that the fused data had little error, and the TDTM was effective and suitable for the logging networks.

关键词： Data fusion fractal interpolation histogram packet switch timestamp

Magnet Demagnetization Observation for Permanent Magnet Synchronous Motor

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Magnet Demagnetization Observation for Permanent Magnet Sync...

TRANSITION TO TAYLOR VORTEX FLOW BETWEEN ROTATING CONICAL CYLINDERS

第11届国际电机与系统学术会议

作者： Xiao Xi Chen Changming Zhang Meng The department of Electrical Engineering Tsinghua university beijing 100084 china The department of Electrical Engineering Tsinghua University Beijing 100084 China

ISBN: (纸本)9787506292214

＜正＞Accurate information of rotor permanent magnet field is needed in permanent magnet synchronous motor（PMSM） control,but this information is variable under demagnetization conditions,such as high temperature or peak current Nonsinusoidal flux density distribution caused by demagnetization induces to torque ripple,which degrades the PMSM drive *** estimate flux magnitude,a Kalman filter is built by using stator current and PM flux as state *** estimation method can accurately track the diversity of permanent flux and is robust to motors’ parameters. The flux linkage is represented by means of Fourier series expansion,and the observe method is used for the online detection demagnetization of *** evaluations of flux linkage are carried out on a DSP-controlled PMSM drive *** results obtained demonstrate the effect of the proposed method.

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Journal of Hydrodynamics 2010年第2期22卷 241-245页

作者： LI Qiu-shu WEN Pu XU Lan-xi department of Mathematics Beijing University of Chemical Technology 100029 Beijing China

Transition to Taylor vortex flow between two conical cylinders,with the inner one rotating and the outer one stationary,is studied by the numerical method in this *** is found that the basic flow becomes unstable with increasing of Reynolds number（Re ） above a certain critical value Rec =117 and with the further increase of Re to about Re=300,the first stable vortex is formed near the top of the flow *** annulus is filled with six pairs of vortices at about Re=*** are confirmed by experimental ***,the local extreme values of pressure and velocity are reached at the adjacent lines between neighboring vortices or at the medium lines of large *** local minimum values of velocity and the local maximum values of pressure are reached at the same point,whereas the local maximum values of velocity of the flow are assumed at the point of inflection for pressure.

关键词： conical cylinder Reynolds number Taylor vortex

Study on flow behavior and structure over chined fuselage at high angle of attack

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Science china(Technological Sciences) 2010年第8期53卷 2057-2067页

作者： TIAN Wei,DENG XueYing ,WANG YanKui,FAN GuoLei&DONG Chao Ministry of Education Key Laboratory of Fluid Mechanics,beijing university of Aeronautics and Astronautics,beijing 100191,china 1. Ministry of Education Key Laboratory of Fluid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100191 China

A study of leeward vortex structure over chined fuselage and the effects of micro tip perturbation on its vortex flow have been carried out in wind tunnel experiments at Reynolds numbers from 1.26×105 to 5.04×105 with PIV and pressure measurement ***,the experiment results have proved that micro tip perturbation has no effects on the vortex flow and its aerodynamic characteristics over chined fuselage at high angle of attack,in which there are not any non-deterministic flow ***,the evolution of leeward vortex structure over chined fuselage along the axis of model can be divided into four flow regimes:linear conical developed regime,decay regime of leeward vortex intensity,asymmetric leeward vortex break down regime and completely break down *** a correlation between leeward vortex structure and sectional aerodynamic force was also revealed in the present ***,the experiment results show the behavior of leeward vortex core trajectories and zonal characteristics of leeward vortex structure with angles of ***,the experiment results of Reynolds number effect on the leeward vortex flow have further confirmed research conclusions from previous studies:the flows over chined fuselage at high angles of attack are insensitive to variation of Reynolds number,and there is a little effect on the secondary boundary layer separation and the suction peak induced by leeward vortex.

关键词： high angle of attack aerodynamics chined fuselage tip perturbation leeward vortex structure zonal characteristics

Cell cycle-dependent gene networks relevant to cancer

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Progress in Natural Science:Materials International 2008年第8期18卷 945-952页

作者： Yun Xiao a,1, Xia Lia,b,*,1, Yueying Yang a, Yadong Wangc, Shaoqi Rao a,b a College of Bioinformatics Science and Technology, and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State, Harbin Medical university, Harbin 150086, china b Biomedical Engineering Institute of Capital Medical university, beijing 10004, china c department of Computer Science, Harbin Institute of Technology, Harbin 150080, china College of Bioinformatics Science and Technology and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin 150086 China Biomedical Engineering Institute of Capital Medical university Beijing 10004 China department of Computer Science Harbin Institute of Technology Harbin 150080 China

The analysis of sophisticated interplays between cell cycle-dependent genes in a disease condition is one of the largely unexplored areas in modern tumor biology research. Many cell cycle-dependent genes are either oncogenes or suppressor genes, or are closely associated with the transition of a cell cycle. However, it is unclear how the complicated relationships between these cell cycle-dependent genes are, especially in cancers. Here, we sought to identify significant expression relationships between cell cycle-dependent genes by analyzing a HeLa microarray dataset using a local alignment algorithm and constructed a gene transcriptional network specific to the cancer by assembling these newly identified gene-gene relationships. We further characterized this global network by partitioning the whole network into several cell cycle phase-specific sub-networks. All generated networks exhibited the power-law node-degree distribution, and the average clustering coefficients of these networks were remarkably higher than those of pure scale-free networks, indicating a property of hierarchical modularity. Based on the known protein-protein interactions and Gene Ontology annotation data, the proteins encoded by cell cycle-dependent interacting genes tended to share the same biological functions or to be involved in the same biological processes, rather than interacting by physical means. Finally, we identified the hub genes related to cancer based on the topological importance that maintain the basic structure of cell cycle-dependent gene networks.

关键词： Cell cycle Microarray HeLa cell Gene network

Correlation between Electronic Structures and Formability of Icosahedrai Quasicrystals in Aluminium-transition metal Binary Alloys

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Rare Metals 1989年第2期9卷 24-30页

作者： Cheng Tianyi Zhang Shouhua department of Materials,beijing university of Iron and Steel Technology beijing Univ of Iron and Steel Technology China

The relation between electronic structures and formability of icosahedral quasicrystals in Al-transition metal binary alloys is investigated *** is found that the number of (s+d) electrons in the transition metals and the parameter |Δ1| which is a measure of the relative bonding between Al and the transition metals are closely related to the formability of icosahedral *** rules of thumb are derived from the experimental results for twelve Al-transition metal alloys.

关键词： Correlation systematically bonding crystalline twelve filled absolutely symmetry metallurgy radius

Alterations of tumor-related genes do not exactly match the histopathological grade in gastric adenocarcinomas

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World Journal of Gastroenterology 2010年第9期16卷 1129-1137页

作者： Guo-Yan Liu,Xiao-Hong Wu,Yi-Zhuo Lu,Chao Pan,Ping Yin,Hong-Feng Liao,Ji-Qin Su,Qing Ge,Qi Luo,department of General Surgery,The Affiliated Zhongshan Hospital of Xiamen university,The Digestive Disease Research Institute of Xiamen university,Xiamen 361004,Fujian Province,china Guo-Yan Liu,Bin Xiong,department of Oncology,The Affiliated Zhongnan Hospital of Wuhan university,Wuhan 430071,Hubei Province,china Kun-Hong Liu,department of Data Mining,Software School of Xiamen university,Xiamen 361005,Fujian Province,china Yong Zhang,Yu-Zhi Wang,The Academy of Military Medical Sciences,beijing 100850,china The Affiliated Zhongnan Hospital of Wuhan university Wuhan 430071 Hubei Province China. binxiong88@***

AIM:To investigate the diverse characteristics of different pathological gradings of gastric adenocarcinoma (GA) using tumor-related ***:GA tissues in different pathological gradings and normal tissues were subjected to tissue *** of 15 major tumor-related genes were detected by RNA in situ hybridization along with 3' terminal digoxin-labeled anti-sense single strandedoligonucleotide and locked nucleic acid modifying probe within the tissue *** data obtained were processed by support vector machines by four different feature selection methods to discover the respective critical gene/gene subsets contributing to the GA activities of different pathological ***:In comparison of poorly differentiated GA with normal tissues,tumor-related gene TP53 plays a key role,although other six tumor-related genes could also achieve the Area Under Curve (AUC) of the receiver operating characteristic independently by more than 80%.Comparing the well differentiated GA with normal tissues,we found that 11 tumor-related genes could independently obtain the AUC by more than 80%,but only the gene subsets,TP53,RB and PTEN,play a key *** the gene subsets,Bcl10,UVRAG,APC,Beclin1,NM23,PTEN and RB could distinguish between the poorly differentiated and well differentiated *** of a single gene could obtain a valid ***:Different from the traditional point of view,the well differentiated cancer tissues have more alterations of important tumor-related genes than the poorly differentiated cancer tissues.

关键词： Pathological grading Gastric adenocarcinoma Tumor-related gene Support vector machine RNA in situ hybridization

NUMERICAL SIMULATION OF TRANSIENT CUTTINGS TRANSPORT WITH FOAM FLUID IN HORIZONTAL WELLBORE

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Journal of Hydrodynamics 2009年第4期21卷 437-444页

作者： WANG Rui-he CHENG Rong-chao WANG Hai-ge BU Yu-huan College of Petroleum Engineering China University of Petroleum Dongying 257061 China CNPC Drilling Research Institute Beijing 100195 China

With considering the interlayer mass transfer and fluid influx from the reservoir, a one-dimensional two-layer hydraulic model was established to describe the mechanism of transient cuttings transport with foam fluid in horizontal well section. The model was numerically calculated based on the modified SIMPLE algorithm, and the height of cuttings bed was predicted by the trial-and-error method. Sensitivity analysis was conducted on the affecting factors on the cuttings transport performance. Results show that cuttings deposition moves along the horizontal wellbore from the drilling bit, and finally achieves a steady state with dynamic balance. Dimensionless cuttings bed height decreases with the increase of foam quality or foam flow rate, but increases with the increase of drillpipe eccentricity, cuttings size or drilling rate. The influx of water and gas from the reservoir is helpful to improve the cuttings transport efficiency with foam. The proposed model offers theoretical guidelines for hydraulic parameter design and hole cleaning control in foamed horizontal drilling.

关键词： foam fluid horizontal wellbore drilled cuttings theoretical model numerical simulation

Application of Cointegration to Forecasting Foreign Trade in china

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Systems Science and Systems Engineering 2000年第4期10卷 420-428页

作者： WANG Zhen\|quan 1,2 ,\ XU Shan\|ying 1 1. Academy of Mathematics and System Sciences, The Chinese Academy of Sciences, beijing 100080, china 2. department of Economic Management, Nanhua university, Hengyang 421001, china

Monthly forecast of export and import of china is investigated in this paper. Export, import, exchange rates and foreign reserve of china are coincided with in a vector error corrected model, on which seasonal export and import can be forecasted in a reasonable precision. With impulse response analysis, impact of exchange rate to export is discussed.

关键词： foreign trade forecast cointegration empirical stu