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The Direction of Marketing in E-commerce

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厦门大学学报（自然科学版） 2002年第S1期41卷 263-264页

作者： ZHANG Wu-yi 1, WEN Shu-hui 2, PENG Lan-ping 3.(1. school of management, Huazhong University of Science and Technology, Wuhan 43.074, china 2. Department of management, Kunming University of Science and Technology, Kun ming 650093. china 3. Human Resource Bureau of Yunnan Province)

E-commerce is the execution of business transactio ns over the Internet. Companies conducting e-commerce can perform most of the tra nsactions which they are doing now. Most of the marketing method should coincide nt with the changes in e-commerce world. Brand ability will be depressed, but corporate identity and brand identity will be upgraded. So the enterprise should lower the cost of distribution, manufactur ing, and supplying. We can also upgrade the product value which consumer con ceded. Logistic will be core ability. The 3.l and 4pl will be used more and more often. The importance of transportation has grown with the increasing globalization as well as the growth in e-commerce. Firms should identify various transportation network design options and their relative strengths and weaknesses. They should also use methodologies for routing and scheduling deliveries in transportation network. The savings matrix and the generalized assignment methodology can be us ed to minimize the transportation cost while meeting delivery commitments to cus tomers. Information is essential to making good decisions. Information technology provid es the tools to gather information and analyze it in order to make the best deci sions. Information plays a key in every company. Information technology will be used broadly. It is a factual component on which decisions about each of the transportation, facilities, and inventory. In essence, information is the glue that holds the company to other firms, and allows it to function, making informa tion the most important firms drivers. Custom relation management, data based marketing, one to one marketing, electron ic odder system, electronic data exchange, will be used frequent. These new mark eting method is using information technology all. IT investment in program will greatly increase. The consumer can find and compare the price in every character easily on Interne t. Cost becomes the most important factor in product selecting. So the e

关键词： marketing e-commerce direction

Local asymptotic behavior of the survival probability of the equilibrium renewal model with heavy tails

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Science china Mathematics 2005年第3期48卷 300-306页

作者： JIANG Tao & CHEN Yiqing school of Finance. Nanjing University of Finance and Economics, Nanjing 210003. china school of Economics and {3., Guangdong University of Technology, Guangzhou 510090, china school of Finance Nanjing University of Finance and Economics Nanjing China school of Economics and management Guangdong University of Technology Guangzhou China

Recently, Tang established a local asymptotic relation for the ruin probability to the Cram(e)r-Lunbderg risk *** this short note we extend the corresponding result to the equilibrium renewal risk model.

关键词： geometric sums, heavy-tailed distribution, ladder height, the equilibrium renewal model, the ruin probability.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4, YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research Center for Remote Sensing and GIS, school of Geography, Beijing Normal University, Beijing 100875, china 2. State Key Laboratory of Remote Sensing Science, Beijing 100875, china 3. Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, Beijing 100875, china 4. Department of Information management, College of Information and Electronic Engineering, china Agricultural University, Beijing 100083. china Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

New lower bounds of classical Ramsey numbers R(6,12), R(6,14) and R(6,15)

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Chinese Science Bulletin 1998年第10期43卷 817-818页

作者： LUO Haipeng 1, SU Wenlong 2 and LI Qiao 3.1. Guangxi Academy of Sciences, Nanning 53.03., china 2. Wuzhou First Middle school, Wuzhou 543.02, china 3. Shanghai Jiaotong University, Shanghai 20003., china Guangxi Academy of Sciences Nanning China Wuzhou First Middle school Wuzhou China Shanghai Jiaotong University Shanghai China

Three new cyclic graphs are constructed by using a computer, and the lower bounds of three Ramsey numbers obtained: R(6,12)≥224, R(6,14)≥258,R(6,15)≥3.8, which fill in three blanks in the table of bounds of Ram... 详细信息

关键词： Ramsey number lower bound cyclic graph.

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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Science china(Technological Sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2 & FENG Xueshang1,3.1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space Science and Applied Re-search, Chinese Academy of Sciences, Beijing 100080, china 2. Graduate school of the Chinese Academy of Sciences, Beijing 10003., china 3. school of Geophysics and Geoinformation Systems, china University of Geosciences, Beijing 100083. china SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate school of the Chinese Academy of Sciences Beijing China school of Geophysics and Geoinformation Systems China University of Geosciences Beijing China

Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3. The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 3.% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

Allocation of power generating and shipping of Hanjiang upstream cascade

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Progress in Natural Science:Materials International 2005年第8期15卷 733-741页

作者： LIU Junping1* and CHANG Mingqi 2,3.1. school of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 3.0014, china 2. Institute of Water Resources & Hydroelectric Engineering, Xi'an University of Technology, Xi'an 710048, china 3. Shanxi Institute of Water Resources, Taiyuan 03.001, china) school of Civil Engineering and Architecture Zhejiang University of Technology Hangzhou 310014 China Institute of Water Resources and Hydroelectric Engineering Xi'an University of Technology Xi'an 710048 China Shanxi Institute of Water Resources Taiyuan 030001 China

The optimal model and simulating model of the Hanjiang cascade reservoirs operation with one day as its calculating period are established to coordinate the contradictions between power generating and shipping. The optimal model is solved by progressive optimality algorithm method adopting the theory of large system decomposing and coordinating. By analyzing the water allocation results obtained from six schemes, which are two cascades, four cascades and seven cascades joint operation considering shipping or not, the contradiction degree between power generating and shipping is investigated and some joint operation schemes are proposed.

关键词： cascade power generating contradiction shipping optimal operation.

Probability parametric imaging with DCE-MRI data to identify prostate cancer in the peripheral zone

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Progress in Natural Science:Materials International 2006年第9期16卷 948-953页

作者： HUANG Xinrui, WANG Qiang, XU Yufeng, WANG Xiaoying and BAO Shanglian ( The Key Laboratory of Medical Physics and Engineering, Peking University, Beijing 100871, china The Medical school of Peking University, Beijing 100083. china 3. The First Hospital of Peking University, Beijing 10003., china) The Key Laboratory of Medical Physics and Engineering Peking University Beijing 100871 China The Medical school of Peking University Beijing 100083 China The First Hospital of Peking University Beijing 100034 China

To quantitatively analyze prostate dynamic contrast-enhanced magnetic resonance images (DCE-MRI), a retrospective study was carried out to construct a mathematical model to predict whether a lesion is cancerous or not. With known diagnosis of 52 re-gions-of-interest (10 malignant, 26 benign and 16 normal) in peripheral zone (PZ) of prostate from 18 patients undergoing needle biopsy and 8 normal volunteers, we combined feature parameters (k1, k2 and tp) from the linear-slope model with logistic regression to determine the statistical probability model. Prostate cancerous probability maps were derived using the model on each subject to examine the correlation between the model-based prediction and the known diagnosis. Compared the model prediction results of 52 regions-of-interest with the histopathologic results, the total agreement rate was 90.4 % ; the agreement rate was 60 % for the malignant and 97. 6 % for the nonmalignant. The diagnostic results only referencing the probability maps by two radiologists showed a high agreement in tissue characteristics and lesion location with the combining results from other diagnostic techniques such as PSA (prostate specific antigen) level and MRS (magnetic resonance spectroscopy) .

关键词： time-intensity curve prostate DCE-MRI logistic regression probability parametric image.

On the siltation of the middle Yangtze River

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Science china Earth Sciences 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2, LI Chang抋n1 & WEI Yuan3.1. school of Earth Sciences, china University of Geosciences, Wuhan 43.074, china 2. Hydrogeological Team, Hubei Bureau of Geology and Mineral Resources, Jingzhou 43.100, china 3. Geological Survey of Jiangxi Province, Nanchang 3.0201, china school of Earth Sciences China University of Geosciences Wuhan 430074 China Hydrogeological Team Hubei Bureau of Geol./Mineral Rsrc. Jingzhou 434100 China Geological Survey of Jiangxi Prov. Nanchang 330201 China

About 5.2×108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. The middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2×108 t/a are deposited within the river artery and lakes, while ca 4.83.108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-Wuhan-Huangshi Segments with Wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 203. m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. This factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-Wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3.1. school of Surveying and Landing Information Engineering, Henan Polytechnic University, Jiaozuo 454003. china 2. College of Geoscience and Surveying Engineering, china University of Mining and Technology, Beijing 100083. china 3. Surveying and Mapping Press, Beijing 100045, china school of Surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China College of Geoscience and Surveying Engineering China University of Mining and Technology Beijing 100083 China Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor