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THE LAND USE INVESTIGATION IN TIBET PLATEAU USING REMOTE SENSING TECHNOLOGY
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作者 Liu Jiyuan(The Institute of Remote Sensing Application, Academia Sinica, Beijing) 《遥感信息》 CSCD 1990年第A02期5-6,共2页
Tibet Plateau is Known as "the Roof of the World" with the area of 1,220,000km^2, which is about 1/8 land area of China. Because of the high elevation, cold climate and it caused difficulties in regional eco... Tibet Plateau is Known as "the Roof of the World" with the area of 1,220,000km^2, which is about 1/8 land area of China. Because of the high elevation, cold climate and it caused difficulties in regional economic planning and land resources management. Since 1985, the land use investigation in Tibet has been carried out, in which the basic data and thematic maps must be obtained and completed at county and township levels, in order to meet the needs of local administrations. In the investigation, remote sensing technology was comprehensively adopted. At present, the investigation in county level had been completed and the compilation is going to be carried out. Due to paying a great attention to studying on a series of key technical problems, the systematic methods of using remote sensing technology in the plateau land use investigation were formed and successfully put into application. 展开更多
关键词 DATA THE LAND USE INVESTIGATION IN TIBET PLATEAU USING REMOTE SENSING technology
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Investigation of Architecture and Essential Technologies of Wireless Sensor Network 被引量:1
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作者 Peng Mugen, Wang Yingjie, Wang Wenbo (School of Telecommunications Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China) 《ZTE Communications》 2005年第4期25-32,共8页
This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing proto... This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing protocols are discussed and compared. A proposal of applying the simple IEEE 802 MAC protocol into the wireless sensor network is introduced. In addition, in order to improve the system capacity, a multi-channel strategy for the sensor nodes is presented for decreasing the blocking probability and suppressing the accessing time delay. It is concluded that there are still a number of problems to be solved, including decreasing power consumption, improving capacity and avoiding access collision, to promote the successful commercial application of wireless sensor network. 展开更多
关键词 IEEE WSN Investigation of Architecture and Essential Technologies of Wireless Sensor Network NODE MAC
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Mass transfer mechanisms in fixed-bed adsorption of erythromycin 被引量:2
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作者 Ying SUN Jiawen ZHU +2 位作者 Kui CHEN Sheng ZHU Jie XU 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2008年第4期353-360,共8页
The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performa... The equilibrium and kinetic characteristics of the adsorption of erythromycin to Sepabeads SP825 were determined.The equilibrium data in a batch system was well described by a Langmuir isotherm.The separation performance was investigated in a fixed-bed system with respect to the adsorption superficial velocity,ionic strength and pH.A mathematical model was used to simulate the mass transfer mechanism,taking film mass transfer,pore diffusion and axial dispersion into account.The model predictions were consistent with the experi-mental data and were consequently used to determine the mass transfer coefficients. 展开更多
关键词 fixed-bed adsorption superficial velocity ionic strength erythromycin However investigations on the parameters governing the performance of this technology are still scarce.In the present work a polymeric and porous resin Sepabeads SP825 resin was used for its higher adsorption efficiency compared with the resins reported.The equilib-rium capacity of Sepabeads SP825 for EM in a batch system was established using a Langmuir isotherm.The effects of superficial velocity ionic strength and pH on the adsorption process were determined from the results of fixed bed experiments.And a model of the purification process was used to simulate the mass transfer mechanism which has taken film mass transfer pore diffusion and axial dispersion into account.The experimental adsorp-tion measurements were compared to the results calcu-lated from the model.The completion of these studies provide some essential parameters which are required in order to design a successful purification process and better understand the fundamentals of these process.
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