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51.
王宁练  薄健辰 《冰川冻土》1997,19(2):167-172
探讨山谷冰川稳定状态时积累区面积比率,即AAR值的大小,认为冰川物质平衡高程分布,平面形态及坡面坡度沿程变化形式是影响山谷冰川稳定态AAR值的主要因素,并 山谷冰川稳定态AAR值与物质平衡高程分布及平面形态之间的定量关系。山谷冰川适合于应用AR值法来研究古冰川的零平衡线高程。  相似文献   
52.
Parameters of Land-Surface Processes for Gobi in North-West China   总被引:1,自引:0,他引:1  
Using data from the intensive observation period (May–June 2000) of the NWC-ALIEX (The Field Experiment on Interaction between Land and Atmosphere in Arid Region of North-west China), the characteristics and mechanisms of some key land-surface process over Gobi in a typical arid region of north-west China are analyzed and several parameters of land-surface processes are calculated. The weighted mean of the surface albedo over a typical arid region of the Dunhuang Gobi is calculated using the relative reflection as a weighting factor, and its value is 0.255 ± 0.021. After removing the influence of precipitation, the mean soil heat capacity over a typical arid region of the Dunhuang Gobi is 1.12 × 106 J m-3 K-1,which is smaller than that observed in the Heihe (China) River basin Field Experiment (HEIFE). The mean soil heat diffusivity and conductivity are about half of those observed in HEIFE.  相似文献   
53.
碎石桩复合地基抗液化设计方法的分析   总被引:2,自引:2,他引:2  
对碎石桩复合地基抗液化设计方法进行了分析评价 ,并对施工技术作了介绍。基于复合地基抗地震液化作用的分析 ,提出一种合理的抗液化设计方法 ,该方法能够体现碎石桩复合地基的加密、排水和减震三方面的抗地震液化作用。  相似文献   
54.
Among various image fusion methods, intensity-hue-saturation (IHS) technique is capable of quickly merging the massive volumes of data. For IKONOS imagery, IHS can yield satisfactory "spatial" enhancement but may introduce "spectral" distortion, appearing as a change in colors between compositions of resampled and fused multispectral bands. To solve this problem, a fast IHS fusion technique with spectral adjustment is presented. The experimental results demonstrate that the proposed approach can provide better performance than the original IHS method, both in processing speed and image quality.  相似文献   
55.
One hundred and eighty lakes, ponds and reservoirs in Taiwan, and the offshore islands have been investigated since 1985. Effects such as warming/cooling, mixing, photosynthesis and respiration on pH have been identified. These effects were found to be less profound than those resulting from the geology. Since there is little rain or lake water pH data available prior to 1970, it was necessary to use proxy data in order to ascertain the history of lake acidification. In this study, we present data based on diatoms in a sediment core collected from a lake in the remote subalpine region of southern Taiwan. The acidity of this lake water was found to have increased since 1900. We measured the concentrations of 55 chemical species in lake water samples. In addition, concentrations of 26 chemical species were obtained from sediments. Conductivity, alkalinity (HCO3 ?), most other major and minor chemical species, as well as the non sea-salt SO4/Na ratio in lake water clearly decrease with elevation. Distribution of pH is similar, although the trend is less clear. Distribution of trace metals, however, shows a different trend as anthropogenic pollution, diagenetic reduction and lake acidification are at play.  相似文献   
56.
The Singapore River thematic zone: sustainable tourism in an urban context   总被引:5,自引:0,他引:5  
This paper explores the concept of sustainable tourism and how it applies to urban destinations such as Singapore. As tourism is an important industry in Singapore, in terms of employment, business activity and an income generator, the Singapore Tourism Board is continuously looking at potential avenues to make Singapore a competitive destination. We examine the use of thematic zones in Singapore as a strategy to achieve its ambition of becoming a tourism capital of the world. By focusing on a case study of the Singapore River thematic zone (one of the 11 thematic zones identified by the Singapore Tourism Board), we assess the viability of thematic zones in ensuring sustainable urban tourism. The paper closes with some theoretical reflections and policy implications arising from our key findings.  相似文献   
57.
数字化形变台站日常下载、处理直至管理数据,都应用《数字化通讯控制软件》、《形变前兆台站(网)数据处理系统》及《形变前兆数据库服务软件(台站版)》等三个软件交互进行,在实际使用过程中会遇到一些棘手的问题。本文结合我台的观测工作的实践,总结经验,以供台站同行共享。  相似文献   
58.
INTRODUCTIONAs a new and effective method for withstandingthe horizontal component of earthquake motion on abuilding structure, the base isolation technique hascome to the engineering application phase ( Hu,1988). However, for some important buildings andfoundation facilities in an earthquake region, it is im portant to consider the effects of 3D aseismatic analy sis, including the vertical component, due to themulti dimensional characteristics of earthquakes (Suand …  相似文献   
59.
Wang  Zhi-wei  He  Yan-ping  Li  Ming-zhi  Qiu  Ming  Huang  Chao  Liu  Ya-dong  Wang  Zi 《中国海洋工程》2021,35(6):914-923
China Ocean Engineering - Numerical simulations of evolution characteristics of slug flow across a 90° pipe bend have been carried out to study the fluid—structure interaction response...  相似文献   
60.
We present the observational results from a detailed timing analysis of the black hole candidate EXO 1846-031 during its outburst in 2019 with the observations ...  相似文献   
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