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121.
激电法预报地下涌水量的回归分析方法研究 总被引:3,自引:1,他引:3
本文介绍经验回归函数的建立,回归系数的显著性检验及回归预测方法,并以山西五台山北麓峪河洪积扇找水实测资料为列,分析了激电参数与富水性之间存在相关性。 相似文献
122.
东北老工业基地衰退机制与结构转换研究 总被引:18,自引:3,他引:15
分析“东北现象”及世界主要老工业基地发展衰退特征,运用产业结构结构增长理论,探讨了我国东北老工业基地和世界主要老工业基地发展衰退的制约因素,归纳,总结了老工业基地发展的衰退机制,在分析,借鉴国外老工业基地改造成功经验的基础上,提出了我国东北老工业基地改造与振兴的目标、途径和措施。 相似文献
123.
Rates of waterfall recession, and major factors that influence the rate, were studied using waterfalls in Boso Peninsula, Japan. The mean rate of waterfall recession was estimated by determining the age and original location. The principal factor in determining the rate of waterfall recession is the ratio of the erosive force of stream to the bedrock resistance. This is expressed in terms of measurable variables, which include the discharge (drainage area and precipitation), the width and height of the waterfall, and the unconfined compressive strength of the bedrock. An empirical equation connecting the force/resistance ratios and the rates of waterfall recession is derived. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
124.
125.
YUICHI S. HAYAKAWA HIROYUKI OBANAWA YUKINORI MATSUKURA 《Geografiska Annaler: Series A, Physical Geography》2008,90(1):65-74
Post‐eruptive fluvial erosion of welded pyroclastic flow deposits often depends on the recession of waterfalls because of their rapid erosion involved. We examine the recession rate of Shomyo Falls, which consists of Pleistocene welded pyroclastic flow deposits in Tateyama, north‐central Japan. The mean recession rate of the waterfall obtained from lithological and topographical evidences is 0.08‐0.15 m/a for 100000 a. However, the recession rate estimated by means of an empirical equation comprising physical parameters of erosive force and bedrock resistance is 0.006‐0.011 m/a with small uncertainties. The discrepancy between the geology‐based and equation‐based recession rates indicates that some factors, not taken account of in the equation, significantly influence the recession rate. We suggest that a factor in the rapid erosion of the waterfall is a large amount of transported sediment acting as abrasive material, which is supplied from high mountains in the watershed above the waterfall. 相似文献
126.
Interpreting characteristic drainage timescale variability across Kilombero Valley,Tanzania 总被引:1,自引:0,他引:1
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Steve W. Lyon Alexander Koutsouris Friedemann Scheibler Jerker Jarsjö Rene Mbanguka Madaka Tumbo Keven K. Robert Asha N. Sharma Ype van der Velde 《水文研究》2015,29(8):1912-1924
We explore seasonal variability and spatiotemporal patterns in characteristic drainage timescale (K) estimated from river discharge records across the Kilombero Valley in central Tanzania. K values were determined using streamflow recession analysis with a Brutsaert–Nieber solution to the linearized Boussinesq equation. Estimated K values were variable, comparing between wet and dry seasons for the relatively small catchments draining upland positions. For the larger catchments draining through valley bottoms, K values were typically longer and more consistent across seasons. Variations in K were compared with long‐term averaged, Moderate‐resolution Imaging Spectroradiometer‐derived monthly evapotranspiration. Although the variations in K were potentially related to evapotranspiration, the influence of data quality and analysis procedure could not be discounted. As such, even though recession analysis offers a potential approach to explore aquifer release timescales and thereby gain insight to a region's hydrology to inform water resources management, care must be taken when interpreting spatiotemporal shifts in K in connection with process representation in regions like the Kilombero Valley. © 2014 The Authors. Hydrological Processes published by John Wiley & Sons Ltd. 相似文献
127.
岩石的长期风化作用会造成岩石表面的剥落,这将导致石质文物产生无可挽回的破坏。为了更好地保护它们,需要开展在相同风化环境下岩石风化剥落深度和相对风化速度及其与不同岩性关系的研究。本文以衢州古城墙通仙门的多块岩石砌块为研究对象,利用自制的测量仪器,对不同岩性岩石砌块风化剥落深度和风化速度进行了研究; 通过分析量测结果得出凝灰岩、砂岩、砾岩、含砾砂岩和粉砂岩相对灰岩的风化速度分别为0.005~0.059mm a-1、0.032~0.097mm a-1、0.004~0.058mm a-1、0.021~0.033mm a-1 和0.015mm a-1。研究结果表明:在相同的风化环境之中不同岩石砌块的风化速度从大到小排序为V砂岩V凝灰岩V含砾砂岩 V砾岩V粉砂岩V灰岩,即岩石抗风化能力从强到弱为:灰岩粉砂岩砾岩含砾砂岩凝灰岩砂岩。由此,为石质文物的长期保护以及制定相关的保护措施提供了重要的理论依据。 相似文献