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Mechanisms of ice accumulation in a river bend-an experimental study

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International Journal of Sediment Research 2012年第4期27卷 521-537页

作者： Jun WANG Jue-yi SUI Hong-ya ZHANG Pang-pang CHEN faye HIRSHFIELD School of Civil Engineering Hefei University of Technology Environmental Engineering Program University of Northern British Columbia Prince George Anhui Institute of Architectural and Industry Environmental Science Program University of Northern British Columbia Prince George

In this study,under conditions of different flow and ice discharge,extensive experiments have been carried out in a 180°-bend flume and an S-shaped bend *** phenomenon and mechanisms of ice accumulation in the bend channel have been *** accumulation along the convex bank was normally thicker than that along the concave *** maximum thickness of ice accumulation in the downstream bend channel occurred close to the convex *** difference between the maximum thickness and the minimum thickness of ice accumulation was *** entire ice accumulation became unstable if flow Froude number was *** the flow Froude Number is high,the entire ice accumulation becomes *** Froude Number between 0.035 and 0.060,the bottom surface of ice accumulation became waved in *** changes in Froude number and ice discharge rate can change a channel from a state of no ice accumulation to uniform accumulation over the channel *** higher the ice discharge,the more uniform the ice *** experimental results have been compared with field observations of ice jams at the Hequ Reach of the Yellow River.

关键词： 180°bend flume Frazil ice Ice jam or ice accumulation S-shape bend channel Thickness profile

Influence of anthropic and eco-hydrological factors on the floristic diversity of the herbaceous vegetation around the temporary ponds in Ferlo,northern Senegal

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Journal of Plant Ecology 2022年第1期15卷 26-38页

作者： Ndiabou faye Aly Diallo Moustapha BassimbéSagna Jean Luc Peiry Papa Saliou Sarr Aliou Guisse Département de Biologie Végétale UniversitéCheikh Anta DiopDakarSenegal IRL3189 Environment SantéSociétésCentre National de la Recherche Scientifiques(CNRS)ParisFrance IRL3189 Environnement SantéSociétésUniversitéCheikh Anta DiopDakarSenegal Observatoire international Hommes Milieux-OHMi Tessekere UniversitéCheikh Anta DiopDakarSenegal Observatoire international Hommes Milieux-OHMi Tessekere Centre National de la Recherche Scientifique(CNRS)ParisFrance Departement d’Agroforesterie UniversitéAssane Seck de ZiguinchorZinguinchorSenegal Département de Géographie Universitéde Clermont FerrandClermont-FerrandFrance Japan International Research Center for Agricultural Sciences(JIRCAS) TsukubaIbarakiJapan

Temporary ponds play substantial roles in preserving biodiversity in the *** study investigated the influence of anthropic and eco-hydrological factors on the plant diversity around two grazed ponds and one ungrazed pond in Ferlo,northern *** phytoecological transects were established per *** each transect,homogenous herbaceous vegetation units were identified and characterized(herbaceous cover,exposure,soil texture,soil moisture and pH,average height and slope).The herbaceous flora comprised 55 species,41 genera and 22 families across the three *** of the Poaceae,particularly Eragrostis tremula and Enteropogon prieurii,mostly colonized the grazed ponds,while the ungrazed pond favored other families’species such as Achyranthes sp.,Commelina forsskaolii,Corchorus *** Shannon’s diversity index(H′)of Wendu Marodi(ungrazed pond)was slightly higher(4.9 bits)than that of Belel Lougal and Belel Sow(grazed ponds)with 4.8 and 4.5 bits,*** equitability indices were relatively high in the three ponds(0.85,0.83 and 0.78).Eco-ecological factors distinguished four species’groupings:a Tribulus terrestris grouping colonizing the constraining and over-grazed zones,a Digitaria horizontalis grouping,and Chloris barbata grouping found in the transition zones,and an Achyranthes aspera grouping in the wetlands,where woody plants were strongly present and the anthropic action *** study highlighted the importance of maintaining a landscape mosaic of ungrazed or semi-protected ponds and grazed ponds to preserve the herbaceous floristic diversity in the center of Ferlo(Senegal)and the Sahel in general.

关键词： ponds Ferlo grazing herbaceous vegetation transect

Application of Multivariate Geostatistics in Environmental Epidemiology: Case Study from Houston, Texas

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Journal of Geoscience and Environment Protection 2016年第4期4卷 110-115页

作者： faye Anderson Independent Scholar Port Arthur TX USA

This study represents an example of investigating the associations between the joint exposure to ozone (O3) and particulate matter of sizes less than or equal to 2.5 micrometers in aerodynamic diameter (PM2.5) and cardiovascular disease (CVD) emergency room (ER) visits and chronic obstructive pulmonary disease (COPD) ER visits using multivariate geostatistics in Houston, Texas, from 2004 to 2009. Analyses showed lack of strong pair-wise association among the predictors of O3, PM2.5, wind speed, relative humidity, and temperature. Whereas CVD and COPD ER visits exhibited a strong positive correlation. Both outcomes drastically increased from 2006 possibly due to immigration from neighboring locations. Parametric testing showed that the data differed significantly between the years. Multivariate multiple regression results on the 2009 data showed that PM2.5, relative humidity, and temperature were significant to both CVD and COPD ER visits. Codispersion coefficients were constant which justified the assumption of intrinsic correlation. That is, our predictors had strong influence on the spatial variability of CVD and COPD ER visits. This multivariate geostatistics approach predicted an increase of 34% in CVD ER visits and 24% increase in COPD ER visits, which calls for more attention from policy makers. The use of multivariate geostatistics analyses enabled us to successfully detect the effects of risk factors on both outcomes.

关键词： Multivariate Geostatistics COPD CVD Harris Houston PM2.5 Ozone

Assessing the Association between Heart Attack, High Blood Pressure, and Heart Disease Mortality Rates and Particulate Matter and Socioeconomic Status Using Multivariate Geostatistical Model

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Occupational Diseases and Environmental Medicine 2016年第1期4卷 8-15页

作者： faye Anderson Center for Advances in Water and Air Quality Lamar University Beaumont TX USA

This study addresses the public concerns of potential adverse health effects from ambient fine particulate matter as well as socioeconomic factors. Heart attack, high blood pressure, and heart disease mortality rates were investigated against fine particulate matter and socioeconomic status, for all counties in the United States in 2013. Multivariate multiple regressions as well as multivariate geostatistical predictions show that these are significant factors towards assessing the causal inferences between exposure to air pollution and socioeconomic status and the three mortality rates.

关键词： Heart Attack High Blood Pressure Heart Disease Mortality United States Multivariate Geostatistics Coregionalization Multivariate Multiple Linear

Response to Jesus in Beijing by David Aikman

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金陵神学志 2004年第4期 61-67页

作者： faye Pearson Nanjing Union Theological Seminary Visiting Teacher

After I read Jesus in Beijing by Mr. Aikman I am distressed. I encouraged church leadership to give Mr. Aikman an interview. I knew Mr. Aikman worked for Time Magazine and I had read some of his articles. I am disappo... 详细信息

关键词：《耶稣在北京》书评大卫·埃克曼基督教

Hamilton-Jacobi-Bellman equations for Fuzzy-Dual Optimization

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Multivariate Geostatistical Model for Groundwater Constituents in Texas

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作者： Lunlong Zhong Felix Mora-Camino Hakim Bouadi Roger Marcelin faye Key Lab. for Adv.Signal Proc. Civil Aviation University of China Automation Research Group ENACToulouse University

ISBN: (纸本)9781538629185

In this article, after introducing fuzzy-dual numbers, functions and functionals, the optimization of a fuzy-dual functional is considered through an extension of Euler’s condition. Then, once uncertainty is imbedded in a fuzzy-dual dynamical system, the optimization of such systems is considered, leading to an extended Hamilton-Jacobi-Bellman equation to characterize optimal fuzzy-dual solutions.

关键词： fuzzy-dual numbers uncertain systems Euler’s equation optimal control Hamilton-Jacobi-Bellman equation

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International Journal of Geosciences 2014年第13期5卷 1609-1617页

作者： faye Anderson Texas A & M AgriLife Research Center at Beaumont College Station Texas USA

Although many studies have explored the quality of Texas groundwater, very few have investigated the concurrent distributions of more than one pollutant, which provides insight on the temporal and spatial behavior of constituents within and between aquifers. The purpose of this research is to study the multivariate spatial patterns of seven health-related Texas groundwater constituents, which are calcium (Ca), chloride (Cl), nitrate (NO3), sodium (Na), magnesium (Mg), sulfate (SO4), and potassium (K). Data is extracted from Texas Water Development Board’s database including nine years: 2000 through 2008. A multivariate geostatistical model was developed to examine the interactions between the constituents. The model had seven dependent variables—one for each of the constituents, and five independent variables: altitude, latitude, longitude, major aquifer and water level. Exploratory analyses show that the data has no temporal patterns, but hold spatial patterns as well as intrinsic correlation. The intrinsic correlation allowed for the use of a Kronecker form for the covariance matrix. The model was validated with a split-sample. Estimates of iteratively re-weighted generalized least squares converged after four iterations. Matern covariance function estimates are zero nugget, practical range is 44 miles, 0.8340 variance and kappa was fixed at 2. To show that our assumptions are reasonable and the choice of the model is appropriate, we perform residual validation and universal kriging. Moreover, prediction maps for the seven constituents are estimated from new locations data. The results point to an alarmingly increasing levels of these constituents’ concentrations, which calls for more intensive monitoring and groundwater management.

关键词： Multivariate Geostatistical Groundwater Constituents Texas

LA-ICPMS in-situ U-Pb Geochronology of Low-Uranium Carbonate Minerals and Its Application to Reservoir Diagenetic Evolution Studies

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Journal of Earth Science 2021年第4期32卷 872-879页

作者： Entao Liu Jian-Xin Zhao Hua Wang Songqi Pan Yuexing Feng Qianglu Chen faye Liu Jiasheng Xu State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China Shandong Provincial Key Laboratory of Depositional Mineralization&Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590China Hubei Key Laboratory of Marine Geological Resources China University of GeosciencesWuhan 430074China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China Radiogenic Isotope Facility School of Earth and Environmental Sciencesthe University of QueenslandBrisbane Qld 4072Australia PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

Reconstruction of the diagenetic evolution of reservoirs is one of the most significant tasks in oil and gas exploration and *** the accurate timing of diagenetic events is critical to better understand the process of reservoir evolution,but the isotope dating of diagenetic events is technically *** paper uses three case studies in the sedimentary basins in China to demonstrate the promising application of recently developed LA-(MC)-ICPMS in-situ U-Pb *** results show that the new U-Pb dating method provides a reliable and efficient chronological approach to determine the absolute ages of diagenetic *** example,the U-Pb age data of the Cambrian carbonate reservoir in the Tarim Basin reveals three diagenetic events at 526±14,515±21,and 481±4.6 Ma,*** is worth noting that microscopic observations are particularly important for improving the success rate of U-Pb *** addition,the recent progress and future prospects in the in-situ U-Pb dating method are also discussed in this study,suggesting that this method is currently hindered by the lack of international carbonate standards for data correction.

关键词： LA-ICPMS U-Pb geochronology carbonate minerals diagenetic evolution reservoir sedimentary basin

双作用叶片式二次元件在车辆传动系统中的应用

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农业机械学报 2006年第3期37卷 8-11页

作者：臧发业山东交通学院科研处

通过分析双作用叶片式二次元件的结构和工作原理,得出了应用二次元件的公交汽车传动系统的节能机理,建立了二次调节传动系统的数学模型,在非恒压网络中采用恒功率控制节能制动方式,对二次调节传动系统的动态性能进行了仿真研究,结论表... 详细信息

通过分析双作用叶片式二次元件的结构和工作原理,得出了应用二次元件的公交汽车传动系统的节能机理,建立了二次调节传动系统的数学模型,在非恒压网络中采用恒功率控制节能制动方式,对二次调节传动系统的动态性能进行了仿真研究,结论表明应用二次调节技术能够回收和重新利用系统的制动动能,减小了系统的装机容量,实现了节能降耗。

关键词：车辆叶片式二次元件性能仿真