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221.
移动电子地图技术初探   总被引:3,自引:0,他引:3  
随着嵌入式技术、通信技术、移动定位技术的发展 ,它们为电子地图技术的发展再次提供了难得发展机遇。本文主要探讨了以上技术和电子地图相结合的可行性 ,分析两种移动电子地图在移动定位、数据处理、数据传输等方面实现的技术以及优缺点  相似文献   
222.
Sunarjo 《中国地震研究》2002,16(3):293-297
The establishment of the ASEAN Earthquake Information Center(AEIC) was endorsed by the 40th Meeting of the Committee on Science and Technology held in October 2000,at the request of the ASEAN Sub-Committee on Meteorology and Geophysics(SCMG) to obtain the ASEAN Standing Committee‘s (ASC) approval to officially use the name“ASEAN Earthquake Infor mation Center(AEIC)“,As part of AEIC activities,the SCMG implemented a project on the ASEAN Seismic Network for Rapid Exchange of Strong Earthquake Data(ASNE RESED).The project was implemented by the ASCMG with funding support from the Government of Japan through the Japan ASEAN Co-operation Promotion Program(JACPP).The aim of the project is to facilitate the rapid exchange of data and information on earthquakes with magnitudes greater than 5.5 on the Richter scale,and to link all of the ASEAN National Seismological Centers through the Internet to disseminate earthquake information.For the future program,we propose a seismic data exchange between the National Seismological Centers in ASEAN countries as well as world seismological centers using the facilities in the AEIC,The plan is basically to develop and update the software and hardware in the NSC and AEIC for data communication.To refresh our knowledge in seismology and data communication,we arrange the training sessions for both topics.  相似文献   
223.
基于“北斗一号”导航卫星通讯的滑坡实时监测系统研究   总被引:2,自引:0,他引:2  
介绍了基于中国北斗一号导航通信卫星技术建立的滑坡实时监测系统。该系统由“野外信息采集监测站”、“数字化滑坡自动监测点”、“北斗导航卫星通信系统”和“地质灾害监测分析中心”四大组成部分。在我国有线和GPRS等通讯设施不发达地区,采用基于北斗卫星通讯技术进行滑坡等野外监测数据传输是一种有效的方式。  相似文献   
224.
基于GPS卫星测量的远距离滑坡监测应用研究   总被引:1,自引:1,他引:0  
利用GPS进行远距监控滑坡区并做适用性的评估研究,整合系统中含供电系统(室内及室外电源设置)、无线传输(利用GSM传输)、GPS资料后处理软件及监控软件等。所组合的系统将应用在某滑坡区,进行长时间持续监测。试验方式包含现场模拟试验、滑坡模拟测试,同时以远近两不同距离的主控站来评估此监测系统因基线长短不同所造成的精度影响,以期能通过此研究提出GPS监测系统设置的经验。根据研究成果指出,GPS监测系统应用在滑坡监测上可行,利用无线传输(GSM)可成功将现场的资料传给远程的操作者。试验结果显示,利用近基站观测可提高观测的精度及解算的成功率,但不论在远基线或近基线的试验,GPS监测系统的精度均可达到公分等级。  相似文献   
225.
基于视觉传达设计原则的多媒体地图界面设计探讨   总被引:1,自引:0,他引:1  
首先对各种多媒体电子地图界面设计中的视觉构成要素进行了分析,结合人们在浏览平面媒体信息时的视觉习惯以及对多媒体电子地图界面设计的视觉审美需求,讨论了视觉传达设计理念融于多媒体电子地图界面设计的基本原则和方法,并依据这些基本原则和方法设计试验,并给出了实例。  相似文献   
226.
International English has come to dominate science publication. For both first and second language speakers, the constraints of language for communication in geomorphology are reviewed, including uncertainties with terminology, subtleties of qualification and explanation in the written presentation of arguments, and formalities in the rhetorical structuring of published papers. Distinctive qualities of style and presentation need to be recognized because, in geomorphology as generally, full qualitative meanings may pass lingua franca or second language speakers by, whilst formulaic discourse may disguise shortcomings. The alternative of language simplification for international usage may not be wholly desirable if valued functions are lost. Language is also increasingly being coupled with visual devices, pictorial and diagrammatic images and data tables, which are internationally intelligible. These can leave viewers with greater hermeneutic (text interpretation) freedom, and therefore a variety of outcomes in understanding. Mathematical treatments, with their precision and predictive utility, have great universal value and they leave readers with rather less interpretive freedom. Debate is due, both by first and by second English language geomorphologists, as to how well developing presentation styles in international English suit scientific purposes. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
227.
Physical models are a well‐established tool in education to strengthen hydrological understanding. They facilitate the straightforward visualization of hydrological processes and allow the communication of hydrological concepts, research and questions of general interest to the public. In order to visualize the water cycle in a landscape of postglacial sediments, in particular the subsurface part, a physical model was constructed. In two videos, (1) a detailed construction manual and (2) visualization examples of hydrological concepts and processes are presented. With our contribution, we like to encourage professionals in the field of hydrology to share methods and tools of knowledge transfer and communication of hydrological concepts. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
228.
张晶晶  胡可  陈现春  李鹏  张熙  石鑫 《测绘通报》2019,(4):17-20,31
目前国内各省市北斗CORS服务系统相互独立运行,不同省服务系统账户无法通用,在一定程度上影响北斗高精度位置服务的社会化应用范围。针对此难题,本文基于移动通信技术,提出了一种虚拟通信媒介模式的CORS跨网服务无缝切换通信模型,实现了用户跨省使用北斗高精度服务的无缝切换和实时获取高精度定位数据。该方法不改变目前各省市CORS服务业务流程,且用户无需重新注册账号,即可实现在不同省市使用CORS服务的无缝切换。经测试,该方法实现跨省切换并获得高精度定位数据的平均用时为9.029 s,可应用于多省市跨网服务及国家"北斗位置服务一张网"建设。  相似文献   
229.
230.
Interpersonal communication on online social networks has a significant impact on the society by not only diffusing information, but also forming social ties, norms, and behaviors. Knowing how the conversational discourse semantically and geographically vary over time can help uncover the changing dynamics of interpersonal ties and the digital traces of social events. This article introduces a framework for modeling and visualizing the semantic and spatio-temporal evolution of topics in a spatially embedded and time-stamped interpersonal communication network. The framework consists of (1) a topic modeling workflow for modeling topics and extracting the evolution of conversational discourse; (2) a geo-social network modeling and smoothing approach to projecting connection characteristics and semantics of communication onto geographic space and time; (3) a web-based geovisual analytics environment for exploring semantic and spatio-temporal evolution of topics in a spatially embedded and time-stamped interpersonal communication network. To demonstrate, geo-located and reciprocal user mention and reply tweets over the course of the 2016 primary and presidential elections in the United States from 1 August 2015 to 15 November 2016 were analyzed. The large portion of the topics extracted from mention tweets were related to daily life routines, human activities, and interests such as school, work, sports, dating, wearing, birthday celebration, music, food, and live-tweeting. Specific focus on the analysis of political conversations revealed that the content of conversational discourse was split between civil rights and election-related discussions of the political campaigns and candidates. These political topics exhibited major shifts in terms of content and the popularity in reaction to primaries, debates, and events throughout the study period. While civil rights discussions were more dominant and in higher intensity across the nation and throughout the whole time period, election-specific conversations resulted in temporally varying local hotspots that correlated with locations of primaries and events.  相似文献   
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