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101.
102.
二维中值滤波在电磁测深曲线去噪中的应用 总被引:4,自引:2,他引:2
作者针对目前点距较密的电磁测深(如CEMP)数据处理问题,提出并应用二维中值滤波方法进行数据处理,通过与传统去噪方法相比较,该方法对于压制或消除实测数据中的随机干扰以及强工业电磁干扰的效果更好,同时对于压制静态位移也有明显的作用。 相似文献
103.
Spatial analysis of monthly precipitation in Turkey 总被引:2,自引:1,他引:1
Summary The principal objectives of this paper are to develop and validate an optimum interpolation method for the spatial analysis
of monthly precipitation in Turkey. A two-dimensional optimum interpolation objective analysis scheme has been developed for
the spatial analysis of precipitation. The model is developed for generating statistically optimum interpolation based on
the irregular distribution of meteorological stations. One question that affects the optimum interpolation method and, indeed,
all such techniques, is how many observations should be allowed to influence a given grid point? The method developed in this
paper addresses this question. For the implementation of the method, 52 stations are considered for Turkey, with 30 years
of monthly data at each point. It is observed that each monthly average spatial correlation function shows a monotonically
decreasing pattern based on 15 km interval averages. The method provides high estimation accuracy in dense station locations
such as in northwestern Turkey. Precipitation contour maps obtained by the optimum interpolation method indicate two spatial
trends over Turkey which have not been identified in any previous study.
Received June 24, 1999/Revised April 26, 2000 相似文献
104.
Zekai en 《Mathematical Geology》2000,32(8):985-999
An important factor in the rock quality assessment analysis from discontinuity measurements along a scanline is the correlation of intact lengths. The autorun model and first order autorun coefficient are proposed as a method for objectively quantifying intact length correlation structure and discontinuity occurrences along any scanline. Necessary definitions for the methodology are presented on a quantitative basis such as the alternative intact length percentages and experimental autorun coefficient. An expression is proposed for the number of discontinuity occurrences along a scanline depending on the scanline length, alternate intact length percentages, and the autorun coefficient. Monte Carlo simulation technique is used with a suitable autorun model to verify this expression. A mathematical expression is derived for the expected Rock Quality Designation (RQD) value by taking into account the correlation of the intact lengths. Additional simulations show the validity of the new RQD expression. With the methodology proposed much less engineering experience and judgment are required in estimating the RQD value from scanline measurements. The application of the methodology has been presented for some field data. 相似文献
105.
分析了南京市滑坡发生的自然因素和人为因素,进行了应力分析。找出了工程边坡防治工作中存在的问题。提出了滑坡防治的技术措施和管理措施。 相似文献
106.
S. Cecchini G. Giacomelli D. Haşegan G. Mandrioli O. Mariş L. Patrizii A. Plaian V. Popa L. Ştefanov V. Văleanu 《Astrophysics and Space Science》2000,273(1-4):35-41
The solar neutrino problem could arise from oscillation of one neutrinotype into a secondtype. Neutrinos would have a mass and there could be the possibility ofradiative neutrino decays. We discuss the search for neutrino decaysduring the 1999 solar eclipse: it involves the emitted visible photons,while neutrinos travel from the Moon to the Earth. The concept and themain characteristics of the NOTTE experiment are presented. 相似文献
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109.
为有效进行DRAINMOD-S模型参数的优选,更好地理解参数变化对模拟结果的影响,开展了模型参数灵敏度分析。以南通市九龙垦区暗管排水脱盐试验为例,采用Morris全局定性分析方法检测了DRAINMOD-S模型模拟土壤剖面含盐量时侧向饱和导水率Ksat、水动力弥散系数D、地表最大蓄水深度Sm、相对不透水层深度Im、排水系数Dr及地下水初始埋深W 6个参数的灵敏度。结果表明:Ksat对模拟结果影响最为显著,D、Sm和Dr次之,而W与Im影响最小;各个参数间的非线性作用存在差异,以Ksat最为显著。为保证模型模拟质量,对敏感性参数应提高现场测试精度,在模型运行时,对灵敏度大的参数应进行重点调整,同时也不可忽视非线性作用较强的参数,从而有效地指导模型的参数率定,提高模型的适用性。 相似文献
110.
Levent Şaylan Reiji Kimura Erdenebayar Munkhtsetseg Makio Kamichika 《Theoretical and Applied Climatology》2011,105(1-2):277-286
In this study, variations in carbon dioxide (CO2) fluxes resulting from gross primary production (GPP), net ecosystem exchange (NEE), and respiration (R e) of soybean (Glycine max L.) were investigated by the Eddy Covariance method during the growing period from June to November 2005 on an irrigated sand field at the Arid Land Research Center, Tottori University in Tottori, Japan. Although climatic conditions were humid and temperate, the soybeans required frequent irrigation because of the low water holding capacity of the sandy soil at the field site. Finally, it has been found that the accumulated NEE, GPP, and R e fluxes of soybean over 126 days amount to ?93, 319, and 226 gC m?2, respectively. Furthermore, the average ratio of GPP to R e was 1.4 and the average ratio of NEE to GPP was about ?0.29 for the growth period of soybean. Daily maximum NEE of ?3.8 gC m?2 occurred when LAI was 1.1. 相似文献