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In this article, the Multi-Fractal Detrended Fluctuation Analysis (MF-DFA) method is adopted to study the temperature, i. e., the maximum temperature (Tmax), mean temperature (Tavg) and minimum (Tmin) air temperature, multifractal characteristics and their formation mechanism, in the typical temperature zones in the coastal regions in Guangdong, Jiangsu and Liaoning Provinces. Following are some terms and concepts used in the present study. Multifractality is defined as a term that characterizes the complexity and self-similarity of objects, and fractal characteristics depict the distribution of probability over the whole set caused by different local conditions or different levels in the process of evolution. Fractality strength denotes the fluctuation range of the data set, and long-range correlation (LRC) measures the stability of the climate system and the trend of climate change in the future. In this research, it is found that the internal stability and feedback mechanism of climate systems in different regions show regional differences. Furthermore, the research also proves that the Tavg, Tmax and Tmin of the above three provinces are highly multifractal. The temperature series multifractality of each province decreases in the order of temperature series multifractality of Liaoning > temperature series multifractality of Guangdong > temperature series multifractality of Jiangsu, and the corresponding long-range correlations follow the same order. It reveals that the most stable temperature series is that of Liaoning, followed by the temperature series of Guangdong, and the most unstable one is that of Jiangsu. Liaoning has the most stable climate system, and it will thus be less responsive to the future climate warming. The stability of the climate system in Jiangsu is the weakest, and its temperature fluctuation will continue to increase in the future, which will probably result in the meteorological disasters of high temperature and heat wave there. Guangdong possesses the strongest degree of multifractal strength, which indicates that its internal temperature series fluctuation is the largest among the three regions. The Tmax multifractal strength of Jiangsu is stronger than that of Liaoning, while the Tavg and Tmin multifractal strength of Jiangsu is weaker than that of Liaoning, showing that Jiangsu has a larger internal Tmax fluctuation than Liaoning does, while it has a smaller fluctuation of Tavg and Tmin than Liaoning does. Guangdong and Liaoning both show the strongest Tmin multifractal strength, followed by Tavg multifractal strength, and the weakest Tmax multifractal strength. However, Jiangsu has the strongest Tmax, followed by Tavg, and the weakest Tmin. The research findings show that these phenomena are closely related to solar radiation, monsoon strength, topography and some other factors. In addition, the multifractality of the temperature time series results from the negative power-law distribution and long-range correlation, in which the long-range correlation influence of temperature series itself plays the dominant role. With the backdrop of global climate change, this research can provide a theoretical basis for the prediction of the spatial-temporal air temperature variation in the eastern coastal areas of China and help us understand its characteristics and causes, and thus the present study will be significant for the environmental protection of coastal areas. 相似文献
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通过对山西省农村饮水安全襄汾县试点工程进行水质评价,在进行农村饮水安全工程立'项和建设前,要全面普查供水区不同深度的水质,在工程运行期间和验收前后及供水后也应不定期进行抽查检测,避免漏检某些不可知的污染物,同时避免在农村饮水安全工程中引入其他污染物. 相似文献
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海洋一号C卫星(HY-1C)搭载的海岸带成像仪(coastal zone imager,CZI)为满足大幅宽成像需求,采用双相机组合成像,每台相间使用2片4色电荷耦合光敏元器件(charge-coupled device,CCD)拼接。从严密几何成像模型出发,对相机成像过程中存在的系统误差进行分析,采用一种基于探元指向角的几何定标模型,并结合CZI相机设计特点与几何特性,设计出一套针对HY-1C/CZI的几何定标方案。首先利用CZI参考基准波段影像与高精度参考影像进行绝对几何定标,采用分步迭代的方法对参考基准波段影像内外定标参数进行解算,其次进行波段间相对几何定标,最后得到所有波段影像的几何定标结果。实验结果表明,经在轨几何定标后,平面无控定位精度优于5个像元,影像几何质量得到明显改善,说明所采用的定标模型和方案合理有效。 相似文献
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为提高单部雷达与多部雷达组网探测降水的精度,对地基雷达进行了一致性定标。星载雷达作为标准参考源已应用于S波段天气雷达的一致性定标,但对于C波段天气雷达的适用性仍有待研究。为此,本文选择了位于较高纬度的兰州C波段业务雷达,设计了以星载雷达标定C波段雷达的方法。通过对两个降水个例进行分析发现:定标后的C波段雷达回波强度和降水反演精度均有一定改善。说明采用星载雷达对C波段雷达进行定标也是可行的,这有利于解决西部地区地基雷达组网探测的一致性定标难题,展现了良好的应用前景。 相似文献
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近断层煤层开采时,防隔水煤岩柱的正确留设是防止断层突水事故的重要措施。山东济宁三号煤矿123上01(南)工作面西邻的F8断层落差较大,可能会沟通底部奥陶系灰岩(简称奥灰)含水层,为确保工作面安全回采,需要进行F8断层防隔水煤岩柱尺寸计算。考虑煤岩层真实产状、断层面与煤层产状的空间关系和底板承压水威胁,对《煤矿防治水细则》中断层导水条件下的防隔水煤岩柱尺寸计算方式进行改进,推导出水位到安全防隔水煤岩柱宽度(Ha)在断层面垂足处的水头高度计算公式及改进后的断层防隔水煤岩柱尺寸计算公式。对比计算结果发现:《煤矿防治水细则》原有计算公式在将煤岩层理想化为水平岩层,且取偏小的煤层底板水压值计算的情况下,计算出的F8断层煤岩柱尺寸为112 m,改进公式的计算结果为128.5 m。因改进公式考虑了实际煤岩层产状及与断层面空间关系,且水压取值位置准确,计算结果更为精确,将为矿井安全回采提供更为科学的参考依据。 相似文献
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随着经济的快速发展,人民生活水平的不断提高,我国房地产业获得了极佳的发展机遇,人们对住宅的概念已经远远不止是居住的要求了,特别是住宅消费市场化进程的加快,无论是小区规划、住宅楼的外观设计还是内部格局,都呈现出新的设计趋势。与此同时,也出现了一些忽略专业原则,市场把握不准,盲目追求“时尚”等误区。本人仅从工作实践中谈一谈自己的感受。 相似文献