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Attention Matters: An Exploration of Relationship Between google Search Behaviors and Crude Oil Prices

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Journal of Systems Science & Complexity 2019年第5期32卷 1438-1459页

作者： LI Xin ZHANG Xun WANG Shouyang MA Jian Donlinks School of Economics and Management University of Science and Technology BeijingBeijing 100083China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Department of Information Systems City University of Hong KongTat Chee AvenueKowloonHong KongChina.

Extant studies have suggested that google search volume data can serve as a new and direct measure of investor attention in various research fields such as economy, financial and energy markets. However, it is not clear that whether investor attention influences prices in the same direction in different market states(prices increase or decrease). In this paper, the authors propose a measure of speculative attention, demonstrate its advantages by comparing it with several existing ones, and then adopt a Markov switching autoregressive model and an EGARCH model to examine its influences on crude oil prices in two market states. It is argued that the responses of crude oil prices to investor attention are asymmetrical in the two states of crude oil prices. The empirical study shows that one increase in searches causes a significant positive increase in crude oil prices during oil price surges, and a more significant reduction of prices during oil price collapses. The authors also conduct robustness checks by limiting the sample periods and using other measures, and the results support the asymmetric effect of web search behaviors on crude oil prices.

关键词： Asymmetric response crude oil prices google search investor attention Markov switching autoregressive model

A semantic geographical knowledge wiki system mashed up with google Maps

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Science China(Technological Sciences) 2010年第S1期53卷 52-60页

作者： GAO Yong,GAO Song,LI RunQiang & LIU YuInstitute of Remote Sensing and Geographical Information Systems,Peking University,Beijing 100871,China 1. Institute of Remote Sensing and Geographical Information Systems Peking University Beijing 100871 China

A wiki system is a typical Web 2.0 application that provides a bi-directional platform for users to collaborate and share much useful information ***,computers cannot well understand the wiki pages in plain *** user-generated geographical content via wiki systems cannot be manipulated properly and efficiently unless the geographical semantics is explicitly *** this paper,a geographical semantic wiki system,Geo-Wiki,is introduced to solve this ***-Wiki is a semantic geographical knowledge-sharing web system based on geographical ontologies so that computers can parse and storage the multi-source geographical ***,Geo-Wiki mashed up with map services enriches the representation and helps users to find spatial distribution patterns,and thus can serve geospatial decision-making by customizing the google Maps APIs.

关键词： geo-ontology semantic wiki mashup google Maps

google timeline accuracy assessment and error prediction

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Forensic Sciences Research 2018年第3期3卷 240-255页

作者： Andrea Macarulla Rodriguez Christian Tiberius Roel van Bree Zeno Geradts Netherlands Forensic Institute Den HaagThe Netherlands Delft University of Technology DelftThe Netherlands

google Location Timeline,once activated,allows to track devices and save their *** feature might be useful in the future as available data for evidence in *** that,the court would be interested in the reliability of these *** position is presented in the form of a pair of coordinates and a radius,hence the estimated area for tracked device is enclosed by a *** research focuses on the assessment of the accuracy of the locations given by google Location History Timeline,which variables affect this accuracy and the initial steps to develop a linear multivariate model that can potentially predict the actual error with respect to the true location considering environmental *** determination of the potential influential variables(configuration of mobile device connectivity,speed of movement and environment)was set through a series of experiments in which the true position of the device was recorded with a reference Global Positioning System(GPS)device with a superior order of *** accuracy was assessed measuring the distance between the google provided position and the de facto one,later referred to as google *** this google error distance is less than the radius provided,we define it as a *** configuration that has the largest hit rate is when the mobile device has GPS available,with a 52%*** the use of 3G and 2G connection go with 38%and 33%*** Wi-Fi connection only has a hit rate of 7%.Regarding the means of transport,when the connection is 2G or 3G,the worst results are in Still with a hit rate of 9%and the best in Car with 57%.Regarding the prediction model,the distances and angles from the position of the device to the three nearest cell towers,and the categorical(nonnumerical)variables of Environment and means of transport were taking as input variables in this initial *** evaluate the usability of a model,a Model hit is defined when the actual observation is within the 95%

关键词： Forensic science accuracy error google Timeline linear regression model smartphone location

Normalizing Book Citations in google Scholar: A Hybrid Cited-side Citing-side Method

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Journal of Data and Information Science 2019年第2期4卷 19-35页

作者： John Mingers Eren Kaymaz Kent Business School University of Kent

Purpose: To design and test a method for normalizing book citations in google ***/methodology/approach: A hybrid citing-side, cited-side normalization method was developed and this was tested on a sample of 285 research monographs. The results were analyzed and conclusions ***: The method was technically feasible but required extensive manual intervention because of the poor quality of the google Scholar data. Research limitations: The sample of books was limited and also all were from one discipline —business and management. Also, the method has only been tested on google Scholar, it would be useful to test it on Web of Science or *** limitations: google Scholar is a poor source of data although it does cover a much wider range citation sources that other databases. Originality/value: This is the first method that has been developed specifically for normalizing books which have so far not been able to be normalized.

关键词： google Scholar Book citations Normalization Research evaluation

google Earth影像辅助的农作物面积地面样方调查

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农业工程学报 2015年第24期31卷 149-154页

作者：刘佳王利民滕飞李丹丹王小龙曹怀堂中国农业科学院农业资源与农业区划研究所北京100081

地面样方调查是农作物种植面积遥感监测的重要环节,一般采用差分GPS(DGPS,differential GPS)实地测量的方式实现,是一项耗时、耗力的业务工作。该文利用经DGPS实测点校正后的google Earth影像,以中国农业科学院(万庄)农业高新技术产业... 详细信息

地面样方调查是农作物种植面积遥感监测的重要环节,一般采用差分GPS(DGPS,differential GPS)实地测量的方式实现,是一项耗时、耗力的业务工作。该文利用经DGPS实测点校正后的google Earth影像,以中国农业科学院(万庄)农业高新技术产业园及周边地区范围(3.1 km×2.0 km)为研究区域,探索了基于google Earth影像辅助的农作物面积地面样方调查,比较了该方法与完全采用GPS实地测量在调查精度和效率方面的差异。针对不同的GE影像来源,文中定义基于GE客户端COM API编程下载后的影像为A级影像、经在线GE影像校正后的影像为B级影像、经DGPS实测点校正后的影像为C级影像。与实测的检查点相比,0.5 m以上空间分辨率的A级影像X、Y 2个方向中误差232.7 m,B级影像中误差5.4 m,C级影像中误差1.0 m。B级影像中误差符合《数字航空摄影测量空中三角测量规范》1:25000平地的平面位置中误差不大于8.75 m的要求,C级影像中误差符合1:10000平地的平面位置中误差不大于3.5 m的要求。在测区内选择结构组成简单、中等和较为复杂的3个样方类型,量算B和C级影像的面积量算精度,与DGPS实测面积比较,平均误差仅有0.108%和0.018%。从样方相对位置确定、地块和农田边界的修正3个方面用于地面样方的辅助测量,在业务工作中进行了初步应用,陕西省2015年冬小麦种植面积地面样方调查的实际效果表明,GE影像辅助调查比GPS实测方法在时间方面减少了64.2%,路程节约82.5%,调查效率提高了73.3%以上。

关键词：作物遥感监测地面样方面积 google Earth 差分地理信息系统

Million Book Project vs google^(TM) Print

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1195-1200页

作者： ST. CLAIR Gloriana University Libraries Carnegie Mellon University Pittsburgh PA 15213 USA

google’s announcement that it intended to digitize all the books in several major research libraries was met with mixed reactions. John Wilkin at the University of Michigan declared “This is the day the world changes,” while Rory Litwin said in Library Juice that the move would “commercialize the great research libraries with a handshake, suddenly and epochally.” The four directors of the Universal Library and Million Book Project have received many questions about the comparative aspects of our work and google Print. My purpose is to compare the two, talking about their genesis, the realities of collections and logistics, and the worries that arise from these realities.

关键词： google Million Book Project Universal Library

基于google Earth的岩层产状测量方法

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西南交通大学学报 2012年第6期47卷 949-954页

作者：蒲浩杨新林赵海峰李健中南大学土木工程学院湖南长沙410075 高速铁路建造技术国家工程实验室湖南长沙410075

针对传统的野外测量方法在自然条件恶劣区域测量难度大、效率低的问题,提出了利用google Earth提供的数字地形和影像数据,通过C#编程实现全球任意区域浅层岩层产状批量快速计算的方法.该方法以google Earth作为三维地理信息平台,通过Goo... 详细信息

针对传统的野外测量方法在自然条件恶劣区域测量难度大、效率低的问题,提出了利用google Earth提供的数字地形和影像数据,通过C#编程实现全球任意区域浅层岩层产状批量快速计算的方法.该方法以google Earth作为三维地理信息平台,通过google Earth COM API实现与google Earth交互,动态提取岩层分界点坐标数据;将WGS84椭球系下的大地坐标通过高斯投影变换为平面坐标,利用最小二乘原理对岩层面方程进行拟合,根据拟合出的平面方程计算岩层产状要素,并通过KML语言实现测量结果的三维可视化.应用实验表明,该方法具有获取数据便捷、可实时调整岩层分界点、计算结果直观可视等优点.

关键词：岩层产状测量 google Earth COM API 高斯投影变换平面拟合可视化

基于google Maps的农业机械作业轨迹监测系统

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农业机械学报 2012年第11期43卷 231-236页

作者：史国滨王熙庄卫东黑龙江八一农垦大学信息技术学院大庆163319 黑龙江八一农垦大学工程学院大庆163319

为满足现代农业机械管理需要,实现农业机械作业调度与实时监控,运用GPS、GPRS和google Maps技术进行有机集成,构建了农业机械作业轨迹监测系统。该系统采用单片机整合GPS模块、GPRS模块实现车载GPS数据无线远程回传,通过google Maps AP... 详细信息

为满足现代农业机械管理需要,实现农业机械作业调度与实时监控,运用GPS、GPRS和google Maps技术进行有机集成,构建了农业机械作业轨迹监测系统。该系统采用单片机整合GPS模块、GPRS模块实现车载GPS数据无线远程回传,通过google Maps API构建Web GIS系统,采用***实现农业机械田间作业管理;以Web Service技术及Ajax技术实现作业轨迹回放、作业实时定位及长度、面积测量等功能。

关键词：农业机械作业轨迹监测 google Maps Web GIS

google Earth在地震应急中的应用

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地震 2008年第1期28卷 121-128页

作者：陈强姜立新帅向华中国地震局地震预测研究所北京100036 中国地震台网中心北京100045

google Earth是当前非常流行的三维虚拟地球仪软件,以在全球范围内提供丰富的遥感影像资源而著称,得到了许多行业的普遍应用。我国目前地震应急指挥工作的GIS数据还是以二维展示为主,引入新技术具有重要的意义。google Earth在我国的地... 详细信息

google Earth是当前非常流行的三维虚拟地球仪软件,以在全球范围内提供丰富的遥感影像资源而著称,得到了许多行业的普遍应用。我国目前地震应急指挥工作的GIS数据还是以二维展示为主,引入新技术具有重要的意义。google Earth在我国的地震应急指挥工作中可以采取如下应用方案:制作并加载行政区划图,发布公众地震信息;与GPS结合,进行救援路线导航与跟踪;根据现场资料建立三维模型,展现地震灾区现场立体场景变化。该应用方案对我国的地震应急指挥改革具有借鉴意义。

关键词： google Earth 地震应急 KML 三维模型