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Field measurement and analysis of turbulence coherence for Typhoon Nuri at Macao Friendship Bridge

Science china(Technological Sciences) 2010年第10期53卷 2647-2657页

作者： SONG LiLi1, PANG JiaBin2. JIANG ChengLin3, HUANG HaoHui3 & QIN Peng3 1 guangzhou Institute of Tropical and Marine Meteorology, CMA, guangzhou 510080, {2. 2.Tongji University, Shanghai 2.0092. {2. 3.guangdong Climate Centre, guangzhou 510080, {2. 1. guangzhou Institute of Tropical and Marine Meteorology CMA Guangzhou 510080 China2. Tongji University Shanghai 200092 China3. Guangdong Climate Centre Guangzhou 510080 China

For the purpose of investigating the turbulent and spatial coherent characteristics of strong wind during typhoon landing period,two 3-dimensional ultrasonic anemometer stations were set up 30 m horizontally apart on the Macao Friendship Bridge to caputure the turbulent wind velocities of Typhoon Nuri. Based on the reliable and representative field measured data,the mean wind speed and direction,turbulence intensity,turbulence integral scale,turbulence power spectra,spatial correlation coefficient and coherence function were statistically evaluated. The field measurement analysis have presented the following results: 1) Two anemometer stations provided consistent results. The mean wind speed variation in time domain presented typical M-shape curves. The strong wind (10-minute mean wind speed higher than 8th grade in Beaufort wind scale) direction changed in a big range up to 12.-degrees-angle,indicating the field measurements scoped over the typhoon landing period. 2. The ratio of the longitudinal,lateral and vertical turbulence intensities of the strong wind in the typhoon eye wall region was 1:0.96:0.36. Compared with the code defined ratio 1:0.88:0.5,the lateral component was larger and the vertical component was smaller. 3) The value of integral scale increased when the eye wall of Typhoon Nuri passed over the field measurement site. Before the center of Typhoon Nuri arrived,the integral scale of the strong typhoon wind was about twice compared with that for the non-typhoon wind. 4) The spatial correlation of the turbulent wind,coherence function curve and the decay factor had significant differences at different times during the typhoon process. In the eye wall of the typhoon,the horizontal spatial correlation was relatively strong and horizontally spatial correlation spectrum decayed slower with frequency increase. The minimum regressed coefficient C in coherence function model was 4.67,which is lower than the code defined low limit. The maximum decay factor w

关键词： typhoon field measurement and analysis turbulence characteristics coherence spectral function

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Analysis on Carbon Emissions from Energy Consumption in Agriculture and Reduction Measures in guangdong Province

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Meteorological and Environmental Research 2011年第7期2卷 66-69,73页

作者： XIE Shu-juan1,2.3 1.guangzhou Institute of Geochemistry,Chinese academy of Sciences,guangzhou 510640,china 2.Graduate University of Chinese academy of Sciences,Beijing 100049,china 3.guangdong academy of social Sciences,guangzhou 510610,china

[Objective] The aim was to study CO2.emissions from energy consumption in agricultural production in guangdong Province and put forward feasible reduction measures.[Method] Based on the data from china Energy Statistical Yearbook and guangdong Statistical Yearbook,CO2.emissions from agricultural energy use in guangdong Province from 2.00 to 2.09 was estimated by using the formula of carbon emissions recommended by Intergovernmental Panel on Climate Change (IPCC),and corresponding reduction measures were put forward.[Result] With the rapid increase of agricultural output and energy consumption,CO2.emissions from energy consumption in agricultural production in guangdong Province showed increasing trend from 2.00 to 2.09,that is to say,increasing from 42..63×104 t C million tons in 2.00 to 605.99×104 t C in 2.09,with annual growth rate of 4.1%.Meanwhile,carbon emissions intensity during energy consumption in agriculture went down in recent ten years,in other words,decreasing from 0.42. t C/×104 yuan in 2.00 to 0.301 t C/×104 yuan in 2.09,and its annual decreasing rate was 3.7%.The variation of CO2.emissions from energy consumption in agriculture mainly resulted from the increase of agricultural output,improvement of energy utilization efficiency,high carbonization in agricultural energy consumption structure and so ***,in order to reduce CO2.emissions from energy consumption in agriculture,it is necessary to vigorously develop rural renewable energy,develop and popularize advanced technology for energy utilization,advance the energy conservation of agricultural machines,establish and improve the macroeconomic control mechanism for carbon emissions from the energy consumption in agricultural production in the further.[Conclusion] The study could provide references for the establishment of policy about reducing carbon emissions from agricultural energy consumption in guangdong Province.

关键词： Energy consumption in agriculture Energy consumption structure CO2.emissions Carbon emissions intensity china

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The Research of Controlling Inclusions in Middle and High Carbon Steel During TSCR

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Journal of Iron and Steel Research International 2011年第S2期18卷 365-370页

作者： LI Lie-jun1, GAO Ji-xiang1,2.(1. School of Mechanical and Automotive Engineering, South china University of Technology, guangzhou 510640, {2., china 2. CSP applying technology institute, GISE, guangzhou 510730, {2.,china) S china Univ Technol Sch Mech & Automot Engn Guangzhou 510640 Guangdong Peoples R China GISE CSP Applying Technol Inst Guangzhou 510730 Guangdong Peoples R China

Based on the characteristics of Thin slab casting and rolling (TSCR) process,using test methods such as SEM,EDS and measuring content of inclusions, the influencing factor of controlling inclusions during producing middle and high carbon steel was studied. The technologies of electric furnace smelting, LF refining and controlling inclusions of tundish were proposed. The inclusions control level of middle and high carbon steel in which the carbon content is 0.3-1.0%, The level reached and even exceeded the level of like product producing with conventional process at home and abroad.

关键词： thin slab casting and rolling (TSCR) middle and high carbon steel inclusions

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Comparison on neural networks and support vector machines in suppliers' selection

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Journal of Systems Engineering and Electronics 2008年第2期19卷 316-320页

作者： Hu Guosheng1,2.& Zhang Guohong3 1. School of Management, guangdong Vocational Coll. of Science and Technology, guangzhou 510640, P. R. {2. 2. School of Computer and Information, Anqing Teacher Coll., Anqing 2.6011, P. R. {2. 3. Adult Education Coll., guangzhou Univ., guangzhou 510405, P. R. {2. [a]School of Management Guangdong Vocational Coll. of Science Technology Guangzhou 510640 P. R. China [b]School of Computer Information Anqing Teacher Coll. Anqing 246011 P. R. China [c]Adult Education Coll. Guangzhou Univ. Guangzhou 510405 P. R. China

Suppliers＇ selection in supply chain management （SCM） has attracted considerable research interests in recent years. Recent literatures show that neural networks achieve better performance than traditional statistical methods. However, neural networks have inherent drawbacks, such as local optimization solution, lack generalization, and uncontrolled convergence. A relatively new machine learning technique, support vector machine （SVM）, which overcomes the drawbacks of neural networks, is introduced to provide a model with better explanatory power to select ideal supplier partners. Meanwhile, in practice, the suppliers＇ samples are very insufficient. SVMs are adaptive to deal with small samples＇ training and testing. The prediction accuracies for BPNN and SVM methods are compared to choose the appreciating suppliers. The actual examples illustrate that SVM methods are superior to BPNN.

关键词： supplier selection supply chain management logistics support vector machine BPNN.

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Simulation of 1991-2.05 Meiyu seasons in the Yangtze-Huaihe region using BCC_RegCM 1.0

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Chinese Science Bulletin 2010年第11期55卷 1077-1083页

作者： HU YaMin1,2.3& DING YiHui4 1 Institute of Tropical and Marine Meteorology, china Meteorological Administration, guangzhou 510080, china 2.guangdong Climate Center, guangzhou 510080, china 3 Chinese academy of Meteorological Sciences, Beijing 100081, china 4 National Climate Center, china Meteorological Administration, Beijing 100081, china Institute of Tropical and Marine Meteorology China Meteorological Administration Guangzhou 510080 China guangdong Climate Center Guangzhou 510080 China Chinese academy of Meteorological Sciences Beijing 100081 China National Climate Center China Meteorological Administration Beijing 100081 China

By using BCC_RegCM 1.0 (RegCM for short) from Beijing Climate Center (BCC), china Meteorological Administration (CMA), the Meiyu season characters over the Yangtze-Huaihe region during 1991-2.05 are simulated. The major conclusions of this study may be summarized as the following: (1) RegCM can reproduce the interannual variation and the spatial distribution of the summertime precipitation and temperature in the Yangtze-Huaihe region. (2. By use of a generalized Meiyu criterion and in accordance with model-calculated precipitation and temperature, the Meiyu onset and ending date have been determined. Compared with the observation, RegCM can simulate the interannual variation of the Yangtze-Huaihe Meiyu with preferable capability for most of the normal Meiyu years (such as 1995, 1997, 2.00, 2.01, 2.02.and 2.04), especially for the rich Meiyu years of 1996, 1998 and 1999. (3) In terms of the average simulation for the recent 15 years, the timings of onset and ending of Meiyu occur on June 1 and July 13, respectively, which are earlier than the climatological observation. For duration, Meiyu persists for 32.d, 3 d shorter than the observation. The index of Meiyu intensity is 2.45, while the climatological one is 3.00. Therefore, RegCM is capable of simulating the climatological Meiyu duration and intensity, while the capability of simulating the onset and ending date of Meiyu still needs to be improved.

关键词：梅雨季节模拟计算长江气候观测发病时间强度指数中国气象局空间分布

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Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South china Sea

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Science china Earth Sciences 2008年第S2期51卷 138-145页

作者： LI MeiJun1,WANG TieGuan1,LIU Ju2.ZHANG MeiZhu2.LU Hong3,MA QinLin2.& GAO LiHui2.1 State Key Laboratory of Petroleum Resources and Prospecting,Earth Sciences and Geoinformatics School,china University of Petroleum,Beijing 102.49,china 2.Southern Oil Exploration and Development Company,Petrochina,guangzhou 510640,china 3 guangzhou Institute of Geochemistry,Chinese academy of Sciences,guangzhou 5102.0,china china Univ Petr Earth Sci & Geoinformat Sch State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China Petrochina So Oil Explorat & Dev Co Guangzhou 510640 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510240 Guangdong Peoples R China

The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South china Sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2.4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.

关键词： dibenzothiophene alkyl dibenzothiophene condensate reservoir filling pathway molecular markers the Fushan Depression

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Steganalysis of stochastic modulation steganography

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Science in china(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2.& HUANG Jiwu1,2.1. School of Information Science and Technology, Sun Yat-sen University, guangzhou 5102.5, china 2. {2. Province Key Laboratory of Information Security, guangzhou 5102.5, china 1. School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China 2. guangdong Province Key Laboratory of Information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

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Research on Negotiating Agent Development

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 633-637页

作者： WEI Ding-guo 1,2., PENG Hong 1 1.Department of Computer Science, South china University of Technology, guangzhou 510630, {2., china 2.{2. Commercial College, guangzhou 51032.,{2., china Department of Computer Science South China University of "technology Guangzhou 510630 Guangdong. China

The paper presents a flexible and effective method of development of negotiating agents. A strategy specification, which is specified by a state chart and defeasible rules, can be dynamically inserted into an agent shell incorporating a state chart interpreter and a defeasible logic inference engine, in order to yield a desirable agent. The set of desirable criteria and rules is required to be justified with different context of the application. Key words automatic negotiation - intelligence agent - defeasible logic - state chart CLC number TP 391 Foundation item: Supported by the National Natural Science Foundation of china (60173051)Biography: WEI Ding-guo (1964-), male, Associate professor, research direction: computer network protocal etc.

关键词： automatic negotiation intelligence agent defeasible logic state chart

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Accurate determination of the plate model based on CCD images with different orientations

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Chinese Science Bulletin 2010年第9期55卷 791-796页

作者： PENG QingYu1,2.3,4 & FAN LiangYan1,2.3,4 1 Joint Laboratory for Astrometry, Dynamics and Space Science, Jinan University, guangzhou 510632. china 2.Department of Computer Science, Jinan University, guangzhou 510632. china 3 Key Laboratory of Optoelectronic Information and Sensing Technologies of guangdong Higher Educational Institutes, Jinan University, guangzhou 510632. china 4 Joint Laboratory for Optical Astronomy, Chinese academy of Sciences, Kunming 650011, china Joint Laboratory for Astrometry Dynamics and Space Science Jinan University Guangzhou China Department of Computer Science Jinan University Guangzhou China Key Laboratory of Optoelectronic Information and Sensing Technologies of guangdong Higher Educational Institutes Jinan University Guangzhou China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Kunming China

The images of the open cluster NGC2.68 are taken using the newly-fitted 2.×2. CCD attached to the 1-m telescope at the Yun-nan Observatory with two different orientations. After the catalogue position of a star from UCAC2.is compared with its corresponding measured position, a surprising result shows that a small field of view (about 7′×7′) exhibits an obvious distortion. Spe-cifically, the polynomial between the standard coordinate (ξ,η) and its corresponding measured one (x,y) for a star in each field of view has significant terms as high as 4th order. Accordingly, the positional measurement accuracy of a bright UCAC2.star can be derived as well as ~7 mas in each direction (60 s of exposure time and near the zenith). This new finding would be important for a CCD image to deliver a highly accurate position in its whole field of view.

关键词： CCD imaging field distortion positional measurement image analysis

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Geomorphological effects of plate movement during Quaternary in china' s tropics

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Journal of Geographical Sciences 2004年第2期 124-129页

作者： ZHANG Weiqiang 1 ,HUANG Zhenguo 2.(1. guangdong Business College, guangzhou 51032., {2. 2. guangzhou Institute of Geography, guangzhou 510070, {2.)

The eastern and western fronts of plate movement in Taiwan Island and Tibetan Plateau respectively are the two major sources of tectonic force for the morphogensis during Quaternary in china's tropics. Seven examples of geomorphological effects of plate movement are enumerated to discuss the differentiation of tectonic landforms in space and time during Quaternary. The tectonic movement tends to be more active since middle Pleistocene. Some phenomena such as the arc-shape mountain systems, volcanism and crustal deformation imply that the juncture zone of eastern and western tectonic forces is located at about 110 o E.

关键词： plate tectonic geomorphological effect china’s tropics

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