OSL测年中CGC法求D_e均值的计算方法之比较分析

光释光测年中等效剂量是计算样品埋藏年龄的一个重要参数,一般通过求多个实验测量值的均值得出。标准生长曲线法是求等效剂量的一种常用且有效的方法,分析讨论了此法计算的等效剂量存在小幅度的系统性的偏大及其原因,提出了改进的方法;展望了CGC法求De均值更优的估计——极大似然估计。     

Growing up and cleaning up: The environmental Kuznets curve redux

Borrowing from the Kuznets curve literature, researchers have coined the term “environmental Kuznets curve” or EKC to characterize the relationship between pollution levels and income: pollution levels will increase with income but some threshold of income will eventually be reached, beyond which pollution levels will decrease. The link between the original Kuznets curve, which posited a similar relationship between income and inequality, and its pollution-concerned offspring lies primarily with the shape of both curves (an upside-down U) and the central role played by income change. Although the EKC literature has burgeoned over the past several years, few concrete conclusions have been drawn, the main themes of the literature have remained constant, and no consensus has been reached regarding the existence of an environmental Kuznets curve. EKC research has used a variety of types of data and a range of geographical units to examine the effects of income levels on pollution. Changes in pollution levels might also be at least partly explained by countries’ position in the demographic transition and their general population structure, however little research has included this important aspect in the analysis. In addition, few analyses confine themselves to an evaluation for one country of the long-term relationship between income and pollution. Using United States CO₂ emissions as well as demographic, employment, trade and energy price data, this paper seeks to highlight the potential impact of population and economic structure in explaining the relationship between income and pollution levels.     

基于星座图改进的QAM盲均衡算法

针对多模辅助算法均方误差高的缺点,提出了两种基于星座图改进的盲均衡算法.首先利用16QAM星座图信息,增加多模辅助算法代价函数中信号点的均衡数目,得到改进的多模辅助算法,与多模辅助算法相比,改进后的算法稳态均方误差更低,而且收敛速度略有提高;其次将改进的多模辅助算法和判决引导算法相结合,根据均方误差调整两种算法的比例,得到的混合算法进一步降低了稳态均方误差.水声信道仿真结果表明:提出的两种算法都可以有效地降低均方误差,适用于对精度要求较高的场合.     

Multiple solutions in preliminary orbit determination from three observations

Charlier’s theory (1910) provides a geometric interpretation of the occurrence of multiple solutions in Laplace’s method of preliminary orbit determination, assuming geocentric observations. We introduce a generalization of this theory allowing to take into account topocentric observations, that is observations made from the surface of the rotating Earth. The generalized theory works for both Laplace’s and Gauss’ methods. We also provide a geometric definition of a curve that generalizes Charlier’s limiting curve, separating regions with a different number of solutions. The results are generically different from Charlier’s: they may change according to the value of a parameter that depends on the observations.     

磁致伸缩微位移驱动器性能测试分析

介绍了磁致伸缩微位移驱动器的工作原理,分析了检测方法,设计了使用双频激光干涉仪作为测量基准的测试平台;对该驱动器的位移的输出特性进行了测试,通过拟合处理对测试结果进行数据分析,可提高超磁致伸缩微位移驱动器的线性度和控制精度,使得驱动器性能改善.基于磁致伸缩效应原理研制的微位移驱动器,具有线性好、分辨率高、精度高等优点,经测试,达到了设定的参数指标要求.     

安徽淮北煤矿富水区被动式超低频电磁探测结果解析

被动式超低频电磁法是一种在地表直接接收来自地下3～3000Hz频段的天然超低频电磁信号,通过对接收信号的处理和解释实现对地下的岩性界面、构造、资源和能源进行探测,拥有巨大开发潜力的地球物理勘探新方法.首先简述了富水区的被动式超低频电磁探测机理,其次结合安徽省淮北市煤矿富水区的探测实例来说明该方法的适用性和局限性.在数据处理上采用曲线叠加平均、平滑和特征深度标定的方法,同时采用了测深曲线和视电阻率等值断面进行地质解释.解释结果和已知钻孔资料对比发现,无论在测深曲线上,还是在断面图上,富水区均具有明显的特征.     

复杂储层识别的地震反演方法及其在塔木察格盆地的应用

随着油气藏勘探开发程度的加深,准确识别复杂储层变得愈发重要,地震反演已成为储层预测的核心技术.本文对蒙占国塔木察格盆地南部凹陷1 800 km²地震资料进行波阻抗反演研究,研究工作包括测井曲线的标准化校正、地质框架模型的准确建立及其它反演参数的正确选取.波阻抗反演结果为研究沉积相划分、砂体空问展布的认识提供了可靠依据,在一定程度上解决了该区主要日的层南屯组沉积物源多、相变快和在地震剖面上无法追踪的问题.     

基于海洋细菌为受试生物的海洋防污剂快速筛选方法

本文研究探索了一种快速简单易行的海洋防污剂室内评价筛选方法。将待测防污剂均匀分散于凝胶溶液中,然后均匀涂布到一定面积的玻璃板上,固化得到含防污剂凝胶测试板,将其置于接种有三种分离自舟山以东海域的优势海洋菌种(编号为Y-16,W-1和F-6)的人工加富海水中,连续培养24h后显微镜下可发现凝胶板表面上细菌菌落,将凝胶板表面细菌淋洗、定容,测定其光密度(optical density,OD)值,计算平均抑菌率,得到吡啶硫酮锌(ZPT)为38.87%,吡啶硫酮铜(CPT)为41.24%,三甲基氧化锡(TBTO)为65.19%,N,N-二甲基-3,4-二氯苄胺(DCDMA)为30.88%,敌草隆(Diuron)仅为15.29%,抑菌性大小为TBTOCPTZPTDCDMADiuron。实验结果表明5种受试防污剂的抑菌性大小为TBTOCPTZPTDCDMADiuron。采用绘制OD-t生长曲线法,分别得到5种防污剂对3种海洋细菌的最小抑制浓度(minimum inhibitory concentration,MIC),TBTO对三种菌的MIC均为0.5×10–3mg/mL;CPT对W-1和F-6的MIC为0.97×10–3mg/mL,对Y-16的MIC为1.93×10–3mg/mL;ZPT对W-1和Y-16的MIC为1.91×10–3mg/mL,对F-6的MIC为0.96×10–3mg/mL;DCDMA对W-1和F-6的MIC为8.46×10–3mg/mL,对Y-16的MIC为×10–342.29mg/mL。其中,Diuron对细菌的生长几乎没有抑制作用。其抑菌性与室内短期挂板结果具有一致性,表明经OD-t生长曲线得到的MIC可作为溶剂可溶型防污剂评价的辅助方法。另外,将本文中室内短期挂板方法应用于不同粒径的氧化亚铜的防污评价,也取得了与文献一致的结果。     

非对称缓和曲线坐标计算方法

本文重点阐述高等级公路非标准缓和曲线的施工放样测量.缓和曲线是设置在直线和圆曲线之间的一种线型,起缓和过渡作用,其目的在于保证车辆由直线进入圆曲线(或由圆曲线进入直线)时的横向稳定,缓和曲线的曲率半径随曲线长度的增加而均匀连续地变小,本文综合了各种情况下的曲线计算,给出了直接计算和间接计算两种计算方法,并用C编写了计算...     

Comparison of the return period for landslide-triggering rainfall events in Japan based on standardization of the rainfall period

The intensity of rainfall events with potential to cause landslides has varying temporal characteristics. In this study, the time at which the 72-h accumulated rainfall reached its maximum was used to standardize the period of rainfall measurement. The proposed standardization of the rainfall period was used in conjunction with the return level of rainfall intensity, obtained from intensity–duration–frequency curves, to investigate rainfall intensity anomalies associated with 10 hazardous rainfall events that triggered numerous landslides at the regional scale in Japan. These landslides included shallow landslides in volcanic and non-volcanic areas, as well as deep-seated landslides. The rainfall events that triggered the shallow landslides were divided into two types: downpours that repeatedly reached close to the 100-year return level within approximately 3–4 h, and accumulated rainfall that reached close to 200–400 mm over longer time intervals but within 72 h. Lithological differences seemed unrelated to the differences between the two types of shallow-landslide-triggering rainfall; however, precipitation >1000 mm was necessary to trigger deep-seated landslides. Although the characteristics of the hyetographs differed markedly among the landslide-triggering rainfall events, all the landslides could have been triggered when the mean rainfall intensity reached the 100-year rainfall level during the standardized period. Thus, the landslide trigger can be evaluated indirectly based on the increase in the return level of the mean rainfall intensity, which could provide a means for estimating the time of landslide occurrence.