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滑坡危险度区划方法及其应用 总被引:5,自引:0,他引:5
在滑坡研究的基础上总结了滑坡危险度区划的研究方法。建立了综合因素分析和本底因素评价的指标体系,提出了综合因素叠加法、本底因素贡献权重叠加法和本底因素模糊判别推理法的区划模型,介绍了这些方法的应用及试验结果。还对滑坡危险度区划研究中存在的3个主要问题进行了讨论:评价指标数量选择、最佳权重确定方法和危险性等级划分的标准。 相似文献
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相对湿度对静电收集型连续测氡仪检定结果的影响 总被引:1,自引:0,他引:1
NR-667A(Ⅲ)型快速连续测氧仪是目前环境氡测量时间响应最短的一种仪器。该仪器在核工业第六研究所标准氡室进行检定时发现,环境相对相对度对仪器检定结果有很大影响。在相对湿度为80%-99%的标准氡室内分别对仪器进行检定,结果在相对湿度为80%时仪器检定合格,而在相对湿度为99%时仪器检定不合格。本从仪器工作原理对检定结果进行。并提出有效的解决方法,当相对湿度太大时,可在仪器进气口安装干燥器对进气进行除湿。 相似文献
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滑坡本底因子贡献率与权重转换研究 总被引:7,自引:0,他引:7
滑坡危险度区划中一个关键部分是对滑坡本底因子权重的确定,求解权重的准确性将直接关系到区划结果的可靠度。本文在研究滑坡本底因子的贡献率与权重互为转换关系的基础上,提出了一种新的求解滑坡本底因子权重的方法——贡献率权重法。采用GIS技术使滑坡本底因子的采集达到定量化,为贡献率统计提供了可靠的数据源。作者通过指标评价,归一化、均值化、概率分析处理,建立了贡献率与权重的转换模型。 相似文献
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本语文论述用测定旋桨几何螺距和仪器摩阻力矩的方法,来确定旋桨流速仪检定方程的主参数K值,其精度可靠、方法简捷、实用和效率高。适用于大批量仪器检定,并有助于实现公式的标准化。 相似文献
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矩张量反演理论是研究深部岩体破裂机制的有效手段,而监测台站/传感器校准对获取准确的矩张量结果十分重要。为求得更加准确的校准系数和矩张量结果,提出一种新的传感器校准方法——搜索校准法。将该方法和监测网校准法分别应用于加利福尼亚州北部的Geysers地热田微震监测数据中,并综合考虑不同震源机制参数、预设校准系数、噪声添加方式及噪声水平等因素的影响,进行两种校准方法有效性对比的理论计算和模拟分析。结果表明:两种校准方法均可通过微震监测数据获得稳定的校准系数,且校准后的震源成分及应力状态分布均更加集中;所有模拟工况下,两种校准方法均可有效降低矩张量反演误差;低噪声条件下,两种方法对应的矩张量反演误差较小且十分接近;混合噪声和高噪声条件下,搜索校准法的准确性和稳定性多优于监测网校准法;进而优选出Geysers地热田微震监测数据更加可靠的矩张量结果。研究思路和结论为微地震矩张量研究提供了进一步指导。 相似文献
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Gamma-ray spectrometer(GRS) is used to detect the elemental abundances and distributions on the lunar surface.To derive the elemental abundances,it is vital to acquire background gamma rays except lunar gamma rays.So GRS would observe background spectra in the course of earth-moon transfer on schedule.But in fact,GRS was not switched on in the course of flying toward the moon.After the CE-1 probe finished one-year mission,GRS car-ried out a test on background data on November 21?22,2008.The authors did conduct research on the methods of background deduction using 2105 hours of usable gamma-ray spectra acquired at the 200-km orbital height by the GRS and more than 5 hours of gamma-ray spectra acquired in the GRS background test.The final research results showed that the method of deducting the background using the minimum counts in the CE-1 GRS pixels is optimal for the elements,U,K and Th.The method applies to such a case that the elemental abundances in the pixel with the minimum counting rate are 0 μg/g and the continuum background counts are constant over the Moon.Based on the method of background deduction,the full energy peak counts of U,K,and Th are calculated. 相似文献
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Two approaches are described to classify aerial radiometric data. The first procedure establishes categories that may correspond with recognized lithologic types, and the second method permits samples to be classified as possible U host or source rocks in the context of mineral-deposit models. The study is based on published analytical data for Th, U, and K concentrations in igneous rock samples and on aerial gamma-ray spectrometer data from the Basin and Range region and the Denver NTMS Quadrangle. The latter data were obtained as part of the U.S. Department of Energy National Uranium Resource Evaluation (NURE) Program. The results for the Basin and Range region are compared with estimates of world abundances for Th, U, and K for various lithologic types.The study demonstrates that radiometric classification of “formation” data and “outcrop” data into lithologic categories can be accomplished in arid regions based on highsensitivity, aerial gamma-ray spectrometer measurements of Th and K. The methods make it practical to use the gamma-ray data to estimate geochemically the degree of regional U enrichment, or depletion, with respect to, Th or K in the search for uraniferous provinces and potential U source or host rocks. 相似文献
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车载γ能谱方法找金是寻找隐伏金矿床的物化探新技术。用它可有效地预测区域金成矿远景区。在冀北等地区(4.91万km ̄2)采用车载γ能谱测量方法,取得地质体内63416个γ能谱测点数据,按地质体大小使用滑动滤波技术,处理区域地质体中的γ能谱数据并绘制了参数分布特征图件。在深入研究γ能谱参数分布特征所反映的区域金成矿地质环境的基础上,建立了一套与区域金成矿相关的γ能谱组合参数,提取了γ能谱参数特征信息。结合地质资料,研究工作地区的金成矿地质环境,预测了两片远景区,部分地区经验证,见有金矿化。研究结果表明,车载γ能谱方法用于区域找金是一种快速、节资、有效的方法。 相似文献
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A new environmental in-ground radioactivity monitoring technique using LiF thermoluminescence dosimeters was tested in the
Culpeper Basin, Northern Virginia. The dosimeters were buried at a depth of 0.45 m (∼ 18 in.) for approximately four months.
There was a significant positive correlation (at the 99.9% confidence level) between the total accumulated radioactivity signal
from the dosimeters and the on-site 100 second gamma-ray spectrometer measurements. The minimum-maximum dose rate from the
buried thermoluminescence dosimeter measurements was 0.06 to 1.08 mR per day (or 2.5 to 44.5μR per hour).
There are two factors which permit better background levels of radioactivity to be established by thermoluminescence dosimeters
compared with other methods for environmental monitoring programs. First is the great sensitivity of thermoluminescence dosimeters
in terms of minimum dose rate that can be registered (mR per month orμR per hour). Second is the fact that accumulation of radioactivity signal over a long period of time tends to eliminate short-term
environmental changes that affect measurements with gamma-ray spectrometers and scintillation counters. 相似文献
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伽马能谱测量在陆地伽马空气吸收剂量率评价中的应用 总被引:2,自引:2,他引:2
2002~200年,国内首次采用就地伽马能谱测量方法在广东珠海市进行了面积性测量,并用该方法定量解释求得的钾、铀、钍含量用Beck公式估算了地表1 m高处的吸收剂量率,同时用塑料闪烁体X-γ吸收剂量率仪在相同测点做了比对测量.2种方法对比结果(514个测点)显示很好的一致性,珠海市区实测吸收剂量率和伽马能谱估算吸收剂量率平均值分别为(145.07±26.5) nGy/h和(162.10±1.51) nGy/h,计算结果与实测结果的相对误差为11.74%. 相似文献
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B. Poovalinga Ganesh S. Aravindan S. Raja A. Thirunavukkarasu 《Arabian Journal of Geosciences》2013,6(9):3249-3256
This paper deals with many calibration methods involved in preprocessing of hyperspectral remote sensing data, while radiation calibration with respect to magnetite minerals without altering image reflectance. Radiometric calibration is the basis and important for both hyperspectral data applications and quantitative remote sensing. While at present there are many methods available for radiometric calibration in the spaceborne hyperspectral data, here, we used the highest spectral resolution Hyperion EO-1 satellite data using a variety of calibration models, which include the calibration model based on atmospheric radiation theory, conversion model as scene dependent such as flat field model, internal average reflectance model, logs residual modified model, and linear model based on the experience of the ground calibration, and so on, and hyperspectral data calibration study was implemented with magnetite mineral. After the above three models contrast, we have arrived at the conclusion that calibration model based on atmospheric radiation theory is the finest radiation calibration method for Hyperion satellite data preprocessing. 相似文献