均值生成函数的周期性延拓在回归分析中存在的问题及其改进方案

针对均值生成函数的周期性延拓在回归分析中存在的回归前提不同,预报因子是预报量的非独立表现等缺点,给出了改进方案。实例分析计算表明：新方案可以有效地消除原方案中存在的非独立虚假相关现象,从而使得筛选出周期性预报因子更加客观。基于本方案所建立的数学预报模型,具有历史拟合率与多步长预报精度基本一致的特点,是一种具有使用价值的长期预报手段,也有一定的隐含周期分辨能力。     

夜光遥感支持下的城市人口核密度空间化及自相关分析

基于福建省福州市鼓楼区街道社区人口统计数据、夜光遥感影像、Landsat8影像,融合核密度与回归方程,绘制30 m栅格空间分辨率的人口密度图并进行空间自相关分析。方法:① 采用核密度方法对69个社区人口计算生成人口密度分布图。建立786个居民小区点的人口密度与夜光遥感的常规QQ分位图,检测出人口密度存在较大的误差区域:五凤街道和洪山镇。② 建立人口密度与夜光遥感、Landsat8线性分解的不可渗透表面影像之间的二元二次回归方程,修正两个区域的人口密度误差。③ 采用高/低聚类分析、热点分析、聚类和异常值分析,得到鼓楼区人口高聚类属性,显示了鼓楼区最大商业圈区域与人口密度最大居民点区域,展示了人口聚类的空间局部差异性格局。结果:① 研究中所采用的人口空间化技术融合了2种空间化方法:核密度与回归方程。生成30 m栅格空间分辨率的人口密度图。② 鼓楼区人口密度均值分为3种类型:11 000、25 000和50 000人/ km²,人口密度分布近似正态分布。③ 当鼓楼区人口密度均值大于33 000人/ km²,不可渗透表面灰度值与人口密度相关性更强。反之,夜光亮度值与人口密度相关性更强。     

用脊回法反演重力异常的多层密度及其界面

将研究区域划分成具有固定宽度的矩形网格，以网格密度和厚度作为模型参数，在此基础上形成重力异常的反演目标函数，计算出对模型参数的偏导数矩阵，然后采用脊回归法对重力异常进行反演而同时得到密度及其界面。以此方法对理论模型进行了反演试验。     

Study on Distribution Rule of Geostress in Qinghai-Tibet Area

The distribution curve of the Ratios of the Average Horizontal Geostress and the Vertical Geostresses(RAHVG) varying with depth and regression equation were obtained in Qinghai-Tibet area of China for the first time by collecting and analyzing 200 in-situ measured geostress results based on the analysis of distribution rule of geostress in China. Then the geostress distribution rule and the characteristics were analyzed, and it is found that the geostress in Qinghai-Tibet area conforms to the geostress distribution rule in China, but the geostress in Qinghai-Tibet area is significantly subjected to tectonic squeezing and the tectonic geostress is very obvious in magmatic rock. The RAHVG of the magmatic rock varying with depth in Qinghai-Tibet area is significantly greater than that in China between the depth of 100 m and 800 m. It shows that the stress of the magmatic rock in Qinghai-Tibet area is significantly subjected to squeezing tectonic. The RAHVG of the sedimentary rock varying with depth in Qinghai-Tibet area is basically consistent with that in China, but the value in Qinghai-Tibet area is greater. It shows that the stress of the sedimentary rock in Qinghai-Tibet area is not significantly subjected to squeezing tectonic. The RAHVG of the metamorphic rock varying with depth in Qinghai-Tibet area is significantly greater than that in China. It shows that the stress of the metamorphic rock in Qinghai-Tibet area is subjected to squeezing tectonic in some degree. This study can provide references to the study of distribution characteristics of geostress in Qinghai-Tibet area. It also has important practical value for underground engineering survey, design, structural analysis and construction in Qinghai-Tibet area.     

不同周期气压波对钻孔体应变仪观测结果的影响

应用相关分析与谱分析方法,研究了天津宝坻、北京东三旗和河北张家口台2003～2006年钻孔体应变与气压之间的关系。分析结果表明,同一台站不同周期的气压波与体应变具有不尽相同的关系,如宝坻台年周期体应变与气压负相关,回归系数为-13.35×10-11/Pa,滞后气压变化62.15天;月周期和日、半日周期体应变与气压均呈同步、线性、正相关关系,回归系数平均值分别为7.489×10-11/Pa和6.301×10-11/Pa。不同台站日、半日周期和月周期气压波对体应变的影响较为接近,而与年周期相比差异较大。根据岩石力学和弹性力学原理,进一步探讨了不同周期气压波与体应变相关性存在差异的原因。     

基于GRNN模型与邻域计算的低丘缓坡综合开发适宜性评价——以乌蒙山集中连片特殊困难片区为例

土地资源是最重要的自然资源,低丘缓坡开发能够为土地资源紧张地区产业发展提供重要的资源保障,而土地开发适宜性评价则是开展低丘缓坡综合开发利用的基础性工作,其核心在于综合评定低丘缓坡未利用地开发的适宜类型及其程度。以乌蒙山集中连片特殊困难片区为例,本研究在明确界定低丘缓坡范围的基础上,构建了低丘缓坡耕地、建设用地开发适宜性评价指标体系并基于GRNN模型划分土地开发适宜性等级;重点关注集中连片土地开发的规模化效益,采用邻域算法对研究区低丘缓坡综合开发适宜性进行评价。研究结果表明,乌蒙山片区低丘缓坡土地开发潜力巨大,耕地、建设用地开发单宜区面积分别为31.37 万hm²和3.84万hm²,其中多宜区面积达1.79 万hm²;而考虑同现有用地类型及土地开发类型的空间邻接关系,基于规模效益原则综合权衡,多宜区中0.84 万hm²更适宜开发为耕地,0.69 万hm²更适宜用于建设用地开发,0.26 万hm²因空间孤立而不作为土地开发区;综合开发适宜性评价确定耕地、建设用地开发区面积分别为27.68 万hm²和2.21 万hm²。研究结果对于乌蒙山片区低丘缓坡综合开发具有重要的实践指导意义。     

中国太阳总辐射的气候学计算法研究(英文)

Angstrom-Prescott公式的气候学计算法是应用较广的太阳辐射模拟方法,其系数一般通过线性回归确定。近年来,许多研究显示该系数存在明显的空间变异性,常见的解决方法是将研究区划分子区域逐个拟合。本研究采用1961-2010时段日照时数与太阳辐射站点资料,以天文辐射为起始值,基于地理加权回归得到全国尺度连续变化的Angstrom-Prescott系数。通过高精度曲面建模方法(HASM)构建的日照时数资料和天文辐射曲面,得到国家尺度太阳辐射曲面。空间非平稳和误差比较检验等结果表明,系数存在显著的空间非平稳性;与已有研究相比,本研究的模拟方法效果较好。     

Factors affecting the durability of selected weak and clay-bearing rocks from Turkey, with particular emphasis on the influence of the number of drying and wetting cycles

Weathering can induce a rapid change of rock material from initial rock-like properties to soil-like properties. The resistance of a rock to short-term weathering is described through a durability parameter called the slake durability index. As durability is an important engineering parameter, particularly for weak and clay-bearing rocks, it was assessed by a number of tests. The main purpose of this study is to assess the influence of the number of drying and wetting cycles and controls of mineralogical composition and strength on durability. For this purpose, 141 samples of different types of weak and clay-bearing rocks were selected from different parts of Turkey, and relationships between the above-mentioned rock characteristics were statistically investigated. The samples were subjected to multiple-cycle slake durability testing, X-ray diffraction (XRD) analysis and uniaxial compression testing. In addition, to assess the influence of mineralogical composition on durability, the mineral contents of the original material and the material passing from the drum of the slake durability apparatus after each cycle were also determined by XRD. The results indicate that the type and amount of clay minerals are the main factors influencing the variations of the slake durability index in all samples. The durability of the clay-bearing rocks studied correlates best with the amount of expandable clay minerals. A strong relationship between the uniaxial compressive strength and the fourth-cycle slake durability index is found only for the marls among the rock types studied. Assessment of gradation results of the spoil pile materials consisting of clay-bearing rocks also reveals that the increase in percentage of fines in old piles is indicative of material degradation, as is evident by multiple-cycle slaking. It is emphasized that two-cycle conventional slake durability testing did not appear to offer an acceptable indication of the durability of weak and clay-bearing rocks when compared with multiple-cyclic wetting and drying. Comments on the performance of the test are made that aim to make the testing process and interpretation of the results more reliable.     

THE METHOD OF CONSTRUCTING IONOSPHERIC TEC BACKGROUND FIELD BASED ON SVR MODEL

There are many factors related to the variations of TEC, and the changes of TEC caused by earthquake only occupy a small portion. Therefore, it is vital how to exclude the ionospheric interference of non-seismic factors accurately in the process of seismic ionospheric anomaly extraction. This study constructed a TEC non-seismic dynamic background field considering the influence of solar and geomagnetic activities. Firstly, the TEC components of half-year cycle and annual cycle are extracted by wavelet decomposition. Then, it establishes a regression model between TEC in which periodic factors are removed and solar activity index, geomagnetic activity index with SVR method(support vector regression)in non-seismic period. Finally, based on the constructed model, the solar activity index and geomagnetic activity index is used to reconstruct aperiodic components of TEC in earthquake's period. From the reconstructed aperiodic components of TEC plus the half-year periodic components and annual periodic components of TEC in the same period, the non-seismic dynamic background field is obtained. Comparing the residuals relative to original TEC values in non-seismic dynamic background field and traditional sliding window background, there are apparent monthly periodic change and semi-annual periodic change in the residuals of sliding window background, which can have obvious impacts on the subsequent seismic ionospheric anomaly detection. In order to test the validity of seismic TEC anomaly detection based on the background field construction method, this paper investigated the long time series TEC anomalies near Wenchuan city(30°N, 100°E)from March 1 to September 26 in 2008. It is found that under the condition of non-seismic disturbance such as solar activity and geomagnetic activity, TEC abnormal disturbance is rarely detected by non-seismic dynamic background field method, when compared with the traditional sliding time-window method. And before the earthquake, more TEC anomalies were detected based on the proposed method, also, they were more intense than those extracted by sliding window method. Therefore, the TEC background field construction method based on SVR(support vector regression)has superiorities in both system errors elimination, which are caused by solar, geomagnetism, the non-seismic ionospheric disturbance events and periodic fluctuations of TEC, and in reducing the false alarm rate of seismic TEC anomaly. Moreover, it can also improve the seismic TEC anomaly detection ability. In addition, this paper analyzed the time-spatial distribution of TEC anomaly before three earthquakes on May 12, August 21 and August 30, 2008. They were mainly negative abnormal perturbations and often distributed on the equatorial side of epicenter.     

地温、气温、气压对精河台水平摆观测的影响

形变台站观测的目标值是地球内力所导致的形变变化。由于形变台站建立在地壳表层,不可避免地要受到各种因素的影响,这也就意味着在观测值序列中不同程度上包含了来自地球外部的信息。为了更好地研究精河台水平摆观测数据中所包含的地球内力所导致的形变,本文分析了地温、气温、气压对精河台水平摆观测值的影响。结果表明,(1)地温和气温是影响精河台水平摆观测值序列年变化的主要因素,其间具有准线性关系;(2)通过直线拟合去掉趋势性变化之后,观测值与气象因素的线性相关性明显增强,说明观测值序列的趋势变化不是气象因素造成的。