Classifying Human Activity Patterns from Smartphone Collected GPS data: A Fuzzy Classification and Aggregation Approach

Smartphones have emerged as a promising type of equipment for monitoring human activities in environmental health studies. However, degraded location accuracy and inconsistency of smartphone‐measured GPS data have limited its effectiveness for classifying human activity patterns. This study proposes a fuzzy classification scheme for differentiating human activity patterns from smartphone‐collected GPS data. Specifically, a fuzzy logic reasoning was adopted to overcome the influence of location uncertainty by estimating the probability of different activity types for single GPS points. Based on that approach, a segment aggregation method was developed to infer activity patterns, while adjusting for uncertainties of point attributes. Validations of the proposed methods were carried out based on a convenient sample of three subjects with different types of smartphones. The results indicate desirable accuracy (e.g. up to 96% in activity identification) using of this method. Two examples are provided in the Appendix to illustrate how the proposed methods could be applied in environmental health studies. Researchers could tailor this scheme to fit a variety of research topics.     

强度折减法在某核电站泵房边坡分析中的应用

对边坡稳定性分别采用按极限平衡法、有限元强度折减法进行二维分析,通过对比计算结果来验证强度折减法分析的准确性与可行性。针对边坡开挖与加固及隧洞开挖的三维效应,采用三维弹塑性有限元强度折减法分析计算边坡的稳定性,计算分析了开挖完成、支护完成条件下边坡安全系数、位移分布、主应力分布、等效塑性应变区和潜在滑动面。结果表明,支护加固可较大提高边坡的稳定安全系数,三维强度折减法分析在岩土工程领域具有明显优势。     

五硼酸铷溶液的物化性质及物种分布

碳酸铷、硼酸化学计量比混合,蒸发溶液,直至五硼酸铷RbB5O8·4H2O晶体析出。经粉末X射线衍射（XRD）、拉曼光谱（Raman spectroscopy）、热重/微商热重/差示扫描量热（TG/DTG/DSC）、原子吸收光谱等实验方法,确定其化学组成及结构。298.15、333.15K时测量溶液的物理化学性质（密度、电导、pH）,并与经验方程进行拟合,研究五硼酸铷溶液的物化性质随浓度、温度的变化规律。根据文献报道的平衡常数,实验测量的pH数据,采用牛顿迭代法进一步研究五硼酸铷溶液中主要存在的硼酸根离子对类型、含量以及物种的形成。     

青海省祁连县大拉洞柏杨沟矿区煤岩层对比研究

通过研究太原组的沉积特征及聚煤变化规律,采用了标志层、煤岩层组合特征、层间距、测井曲线形态等方法,对矿区内煤层、岩层进行了综合对比。确定了该区主要煤层的赋存层位、形态、分布及变化特征,对周边地区找煤工作具有一定的指导作用。     

榆树林油田扶杨油层沉积岩地球化学特征及地质意义

三肇凹陷榆树林油田扶杨油层中泥岩、粉砂岩和砂岩样品主量元素和微量元素地球化学分析表明,多数主量元素含量中等,与全球平均大陆上地壳(UCC)相比,Fe_2O_3、MgO、CaO、Na_2O含量较低,而TiO_2、Al_2O_3、K_2O、MnO含量均略高;样品中的相容元素(V、Cr、Co、Ni等)含量均低于澳大利亚后太古宙页岩(PAAS)和UCC;稀土元素总量为102×10~(-6)~276×10~(-6),平均为188×10~(-6),与PAAS表现出相似的球粒陨石标准化曲线,显示了相似的物源和构造背景。元素间的相关性分析显示大部分元素与SiO_2负相关而与Al_2O_3正相关,说明大部分元素受到黏土矿物吸附作用的影响,石英与长石矿物对这些元素表现出一定的稀释效应。根据主元素物源判别方程图和Th-Hf-Co图投影及La/Hf、(Gd/Yb)N值,扶杨油层物源主要来自后太古宙长英质火山岩,可能卷入了部分再循环沉积岩。通过一系列的构造背景判别图解分析,表明扶杨油层沉积时以大陆岛弧环境为主。在对油层组进行了纵向古气候分析后,认为FI油层组沉积时处于一个构造活动强、干旱的环境中,所形成的沉积岩储层物性更好,是油气勘探开发的重点层位。     

Re–Os geochronology of the Cambrian stage-2 and -3 boundary in Zhijin County,Guizhou Province,China

The black shale series that formed in the Ediacaran–Cambrian transition are important stratigraphic records of the co-evolution of the paleo-ocean, -climate, and -biology. In this study, we measured Re–Os isotopic compositions of the black shale in the Niutitang Formation from the Gezhongwu section in Zhijin, Guizhou Province. The samples had high Re and Os contents, with Re ranging from 21.27 to 312.78 ng/g and Os ranging from 0.455 to 7.789 ng/g. The Re–Os isotope isochron age of 522.9 ± 8.6 Ma implies deposition of the Niutitang black shale predated the Chengjiang Fauna, providing an age constraint for the expansion of oceanic anoxia in the study area. The initial ¹⁸⁷Os/¹⁸⁸Os ratio of 0.826 ± 0.026 indicates that enhanced continental weathering might have triggered the expansion of the oceanic anoxia.     

Isotopic Geochemistry of Evaporite‐Carbonate Sediments in Majiagou Formation Euxinic Systems with Implications for Evaluating Ordovician Northern Shaanxi Epicontinental Sea,Ordos Basin

正Objective The Ordovician Shaanxi salt basin is located in the junction of the North China Sea and the Qilian Sea.In this basin the Majiagou Formation accumulated more than1000m thick evaporite-carbonate sediments,and this basin is divided into east and west saltern sags(ESS,WSS)according to the characteristics of geochemical analysis(Zhang Yongsheng et al.,2014).Isotope stratigraphy of evaporite sediments represents a fundamental tool in     

Correlation analysis between drought indices and terrestrial water storage from 2002 to 2015 in China

Drought monitoring is a key topic in environmental monitoring and assessment although there is still a need to determine the correlation between drought monitoring indices and remote sensing products. We analyzed the correlation between the self-calibrating Palmer Drought Severity Index (sc_PDSI), the Standardized Precipitation Index and the Standardized Precipitation Evapotranspiration Index (SPEI) and terrestrial water storage monitored through the Gravity Recovery and Climate Experiment (GRACE) on a monthly timescale from 2002 to 2015 in China. As a consequence of anomalies in the soil water budget, the highly significant correlation between the sc_PDSI and the GRACE satellite-observed terrestrial water storage suggested that these two datasets are the most suitable for use in monitoring droughts. In comparing the three drought indices, the sc_PDSI was introduced as a means of drought monitoring in the Yangtze, Pearl, Huaihe, Southeast and Songhua River Basins, whereas the SPEI was found to be more applicable to other major river basins, such as the Inland River Basin. These diverse spatial behaviors are caused by the differences between the hydrological droughts characterized by these three drought indices.