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991.
LIU Can-de HE Bao-yin LI Mao-tian REN Xian-you 《中国地理科学(英文版)》2006,16(1):79-82
1INTRODUCTIONThe quality of water is traditionally determined by col-lectingwatersamplesandanalyzingthesamplesin a lab-oratory. However, sampling is very much hard sledding,time-consuming, slow and expensive, and easily in thecontrol of weather conditions, and does not include allwater areas. Satellite estimates of water quality havefound widespread application. Remote sensing instru-ments have been applied in water quality monitoringwith varying success (DANA and RICHARD, 1999;RUDD… 相似文献
992.
智能天线是第三代移动通信的关键技术之一,也是当前信号处理和通信领域的研究热点.在对智能天线算法进行理论分析和仿真的基础上,有必要构建一个灵活、通用的实验平台,用以验证各种智能天线算法的有效性和实用性.探讨了一种基于自适应麦克风阵的智能天线实验平台的实现方法,介绍了该系统的原理、结构和各部分的作用. 相似文献
993.
This study examined the thermal effects of building‘s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external surface. Results indicate that external wall surface temperature and nearby air temperature vary with the change of orientation, height and season. In general, the external wall surface temperature is lower near the ground, and is higher near the roof, than nearby air temperature. But north wall surface temperature is mostly lower than nearby air temperature at the same height; south wall surface temperature during the daytime in December, and west wall surface temperature all day in August, is respectively higher than nearby air temperature. The heat fluxes into and out of external wall surfaces show the differences that exist in the various orientations, heights and seasons. In December,south wall surface at the lower sites emits heat and north wall surface at the higher sites absorbs heat. In April, all external wall surfaces, emit heat near the ground and absorb heat near the roof. In August, west wall surface all day emits heat, and other wall surfaces just show the commensurate behavior with that in April. 相似文献
994.
995.
对疏散星团进行统计研究时,场星的混淆可能是一个严重问题,必须认真对待。本文详细讨论了在估算疏散星团维里(Virial)质量时,正确利用成员概率的重要性。分析表明,只有利用大概率的成员星才能得到合理的星团Virial质量。重新计算后M11的Virial质量为5094μ_⊙,与直接观测到的光度质量的最新结果(4671μ_⊙)符合得很好,维里系数为0.9。 相似文献
996.
997.
Our two newly obtained high-quality 40Ar/39Ar ages suggest that the high-K volcanic rocks of the Lawuxiang Formation in the Mangkang basin, Tibet were formed at 33.5
± 0.2 Ma. The tracing of elemental and Pb-Sr-Nd isotopic geochemistry indicates that they were derived from an EM2 enriched
mantle in continental subduction caused by transpression. Their evidently negative anomalies in HFSEs such as Nb and Ta make
clear that there is an input of continental material into the mantle source. The high-K rocks at 33.5 ± 0.2 Ma in the Mangkang
basin may temporally, spatially and compositionally compare with the early one of two-pulse high-K rocks in eastern Tibet
distinguished by Wang J. H. et al., implying that they were formed in the same tectonic setting. 相似文献
998.
Based on calculations of data from FGGE Level III b, a discussion is made of the energy balance in the 40-50 day periodic oscillation over the Asian monsoon region during the 1979 summer. It is found that the main source of 40-50 day periodic perturbation is the monsoon region extending from central South Asia to Southeast Asia. In the upper layer over the North Pacific subtropical area (10-20oN, 150oE-150oW) pres-sure work turns into kinetic energy that maintains 40-50 day periodic perturbation associated with the variation in position and intensity of the mid-Pacific trough. The mean energy budget in the three-dimensional space (0-30oE, 30oE-150oW, 100-1000 hPa) indicates that the 40-50 day periodic perturbation transports kinetic energy to a seasonal mean and a transient perturbation wind field. 相似文献
999.
Zonal propagation of kinetic energy and convection in the South China Sea and Indian monsoon regions in boreal summer 总被引:7,自引:0,他引:7
CHEN Longxun GAO Hui HE Jinhai TAO Shiyan & JIN Zuhui .Chinese Academy of Meteorological Sciences Beijing China .Nanjing Institute of Meteorology Nanjing China .Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2004,47(12):1076-1084
As early as in the 1980s, Chinese scientists hadfirst proposed that there exits two summer monsoonsystems in Asia, namely the East Asian summer mon-soon (EASM) and the Indian summer monsoon(ISM)[1-4]. The two monsoon systems are quite dif-ferent in characteristics. Since then, such issue andconclusion had been documented and approved by alot of studies in the past two decades, and was appliedin the guideline of the South China Sea summer mon-soon experiment (SCSMEX), which was undertak… 相似文献
1000.
Environmental impact of drainage of Dianzi Iron Mine on the groundwater system of the Dawu Water Supply Base 总被引:1,自引:0,他引:1
Due to growing water extraction for industry and agriculture, the Dawu Water Supply Base, in the east of Zibo, China, has been in a state of serious over-extraction. It will also be affected by the deep drainage of the Dianzi Iron Mine, which will be exploited in 2005. As to the environmental impact on the groundwater system of the Dawu Water Supply Base is concerned, this paper makes a systematic study about the influence of the mine draining on the water-supply environment of the Dawu Water Supply Base by using the numerical model of groundwater system. The result shows that the groundwater level will have an additional drawdown of 1.2–1.8 m/yr by the mine draining alone. The numerical analysis results indicate that the optimal model for determining the best extraction plan is the solution for the contradiction between water supply and water drainage. 相似文献