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1.
预覆盖建设作为固网运营的第一步,直接影响通讯运营商在竞争格局中的地位。业务发展初期,覆盖选址常以客户关系切入或联合室分覆盖进行;进入规模发展阶段,寻找一种符合市场发展规律,结合网络资源情况的选址规划方案显得尤为重要。通过结合Google Earth和Baidu Map两个地图工具的特点,基于预覆盖管理工作的需求进行了应用开发,实现了在线用户交互、智能数据报表、选址策略等互联网的功能应用,为固网业务预覆盖管理工作提供了宝贵思路。  相似文献   
2.
随着世界信息产业和通讯设备制造产业的迅猛发展,手机已经成为人们日常生活中不可缺少的一部分。智能手机日益趋向于移动智能综合服务平台方向的发展。可以预想在未来的世界,手机将为人们提供移动办公、信息分享和获取、电子支付、游戏娱乐等等的服务,而地图导航就是其中一个非常重要的应用服务。  相似文献   
3.
Monitoring the water level and volume changes of lakes and reservoirs is essential for deepening our understanding of the temporal and spatial dynamics of water resources in the Yellow River Basin, with a view to better utilizing and managing water resources. In recent years, there have been many studies on monitoring water level and volume changes in inland waters, but they were mainly focused on radar altimetry and the full waveform LiDAR ICESat, which was retired in 2010. Few studies based on the latest photon-counting LiDAR ICESat-2 have been reported. Compared with previous sensors, ICESat-2 has great advantages in footprint size, transmitting frequency, pulse number, etc, but its performance in monitoring water level and volume changes in inland waters has not been fully explored. Here we investigated the spatial distribution of water level and volume changes of 11 lakes and 8 reservoirs in the Yellow River Basin based on ICESat-2 and Google Earth Engine, and analyzed the factors affecting the measurement uncertainties. In-situ validation of lake level in Lake Qinghai indicates that the Root Mean Square Error (RMSE) of our result is only 7 cm after the reference coordinate system conversion. We found that the water level trend of the natural lake shows significant seasonal variations, while the water level trend of the reservoir shows a sharp rise and fall. In addition, precipitation plays a decisive role in the changes in natural lake levels and indirectly affects the artificial control of reservoirs’ water discharges. The uncertainty of water volume change monitoring is mainly affected by water level measurement uncertainty for lakes, while for reservoirs, that is affected by the combination of water level and area measurement uncertainties. The stability of lake level measurement increases with the increase in photon counts. The introduction of ICESat-2 ATL13 Significant Wave Height might lead larger standard deviation in water level measurement. According to the law of propagation of uncertainty, the uncertainty of the water volume change estimation by the combination of ICESat-2 and GEE is less than 9 %.  相似文献   
4.
平流层通信新思路——谷歌气球计划   总被引:2,自引:0,他引:2       下载免费PDF全文
平流层通信具有低延迟、信道衰落小、造价低廉、机动灵活等特点,在军事应用和应急通信领域都有重要的战略价值,也曾经引起各国的重视,并成为研究热点。然而平流层通信平台的稳定性对各国研究者而言一直是一个挑战,谷歌公司从鸟群飞行中得到启发,开启了Google Loon项目,其目的是为全球偏远地区2/3人口提供速度较快、价格可承受的互联网接入服务,同时为自然灾害发生地区提供通信服务。文中分析了谷歌气球的技术细节,谷歌气球初次试验的情况,以及谷歌气球面临的挑战。谷歌气球计划为平流层通信提供了又一新思路。  相似文献   
5.
Effective conservation planning relies on the accurate identification of anthropogenic land cover. However, accessing localized information can be difficult or impossible in developing countries. Additionally, global medium-resolution land use land cover datasets may be insufficient for conservation planning purposes at the scale of a country or smaller. We thus introduce a new tool, GE Grids, to bridge this gap. This tool creates an interactive user-specified binary grid laid over Google Earth's high-resolution imagery. Using GE Grids, we manually identified anthropogenic land conversion across East Africa and compared this against available land cover datasets. Nearly 30% of East Africa is converted to anthropogenic land cover. The two highest-resolution comparative datasets have the greatest agreement with our own at the regional extent, despite having as low as 44% agreement at the country level. We achieved 83% consistency among users. GE Grids is intended to complement existing remote sensing datasets at local scales.  相似文献   
6.
The practice of Search Engine Optimization (SEO) can significantly increase a website’s search rankings, driving more traffic to the website, and thereby increasing revenue. Three primary SEO strategies are Content, Link Building, and Social Sharing. Our study compares the performance of three similar content-rich websites; each uses a different SEO strategy – one focused on Content only, the second uses Content and proactive Link Building, and the third uses Content and Social Media campaign designed to elicit social mentions and social sharing. We use Google Analytics to collect, analyze, and compare their site traffic, domain authority, search ranks, and ad revenue before and after SEO implementation, over the course of 18 months. Our study suggests that link building and social media both improve website traffic and revenue. Social media can be an effective method for quickly building traffic (for events); however, link building provides better return on investment in the long run.  相似文献   
7.
This study examined whether, and to what extent, driving is affected by reading text on Google Glass. Reading text requires a high level of visual resources and can interfere with safe driving. However, it is currently unclear if the impact of reading text on a head-mounted display, such as Google Glass (Glass), will differ from that found with more traditional head-down electronic devices, such as a dash-mounted smartphone. A total of 20 drivers (22–48 years) completed the Lane Change Test while driving undistracted and while reading text on Glass and on a smartphone. Measures of lateral vehicle control and event detection were examined along with subjective workload and secondary task performance. Results revealed that drivers’ lane keeping ability was significantly impaired by reading text on both Glass and the smartphone. When using Glass, drivers also failed to detect a greater number of lane change signs compared to when using the phone or driving undistracted. In terms of subjective workload, drivers rated reading on Glass as subjectively easier than on the smartphone, which may possibly encourage greater use of this device while driving. Overall, the results suggest that, despite Glass allowing drivers to better maintain their visual attention on the forward scene, drivers are still not able to effectively divide their cognitive attention across the Glass display and the road environment, resulting in impaired driving performance.  相似文献   
8.
为探究长三角地区农宅平面尺寸在宏观区域上的统计规律,基于Google Earth探向功能,以长、宽作为农宅平面尺寸的标示参量,应用频数统计法分析农宅长、宽在环向及径向分析路径上的频数分布特征。统计结果表明:不管是在环向,还是在径向上,农宅长度都是以3到4个自然开间尺寸的占比最大,农宅宽度都是以2到3个自然开间尺寸的占比最大;在环向上,各区域农宅长度、宽度的频数分布较为相似,且其主要占比区间相对稳定,农宅长度在3到4个自然开间尺寸所占比例约为51%,宽度以2到3个自然开间尺寸为主,其比例为70%左右;在径向上,各区域农宅平面尺寸在各开间的比例差异较大。上述方法与结论对区域视角下的农宅节能潜力分析及既有建筑节能改造策略等问题的研究具有方法借鉴与理论指导意义。  相似文献   
9.
随着信息技术的不断发展,计算机技术和网络技术在各行各业中日益被广泛应用。以往的一些科学计算,数据分析都是依靠工作人员的高负荷重复劳动来实现,随着网络开发技术、数据库技术、电子地图等一系列相关技术的相继出现,利用计算机来分析和处理各种序列数据越来越受到相关技术人员的青睐。利用ZedGraph图表控件,实现对地应力监测数据的动态曲线分析,结合Google Maps来实现对监测点的直观呈现,极大地方便了研究人员对地震形成的检测和分析研究。  相似文献   
10.
三维GIS是当今的发展趋势之一.小区三维可视化是构建数字城市的前提和基础.本文分析了目前三维GIS的发展情况.结合小区三维可视化的特殊性,以及兼顾二、三维GIS平台数据一致性,本文选择以Google SketchUp+ArcScene的方法,实现小区三维可视化,特别对日常不易观察的地下管网也实现了三维可视化.  相似文献   
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