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排序方式: 共有229条查询结果,搜索用时 15 毫秒
1.
对当前地震观测仪器的授时技术现状进行阐述,统计并分析测震观测仪器授时终端的缺陷,针对性地提出基于北斗/GPS双模的分体式授时终端的设计,并通过硬件设计制作与软件功能调试,实现与地震数据采集仪器的成功对接。在地震台站试运行期间对所记录地震事件的测试结果验证了授时终端的校时准确性,设计达到预期效果。 相似文献
2.
自智慧地球概念提出后,世界各国给予广泛关注,国内也先后启动了智慧城市建设相关计划。经原国家测绘地理信息局批准,作为智慧临沂建设重要组成部分的智慧临沂时空信息云平台建设也正式启动。该文介绍了智慧城市时空大数据平台建设的必要性及国内外智慧城市时空大数据平台建设的典型结构,阐述了智慧临沂时空信息云平台的主要建设内容,包括时空基准、时空信息大数据中心、时空信息云平台、云支撑环境、智慧应用等方面,并对智慧临沂建设的成果和下一步工作重点进行了总结和展望,为临沂市智慧城市应用打下基础,并为全国智慧城市的建设积累宝贵经验。 相似文献
3.
Transitioning to more efficient and less carbon-intensive heating is a monumental policy challenge in the United Kingdom. However, very few households in the UK—and perhaps even elsewhere—have actual experience with state-of-the-art smart heating systems that may utilize enhanced control or feedback. Drawing from a unique sample of actual adopters of smart heating, this study closely examines the heating preferences, practices, and profiles of homes when they are given smarter heating systems. The study utilizes qualitative household data from the Energy System Catapult’s Living Laboratory of 100 smart homes in Birmingham (West Midlands), Bridgend (Wales), Manchester (Greater Manchester), and Newcastle (Northumberland). We examine the heating preferences and profiles of participants, with findings inductively organized around the themes of temperature, including tradeoffs between comfort, cost, and value; time, including the utility of heat scheduling; and space, including zonal heating controls. We also discuss patterns of learning, the emergence of environmental values, and issues of discomfort. We conclude by commenting on important distinctions between radiant and ambient heat, as well as between scheduled and on-demand heat. The main findings are 1) tradeoffs between comfort, value and cost occur when it comes to smart heating; 2) people want different numbers of warm hours in their homes at very different times; 3) households chose to heat different numbers of rooms; and 4) there are other non-monetary and non-functional aspects of smart heating that households value. 相似文献
4.
新元古代末期是生命演化的关键转折期,也是以微生物占主导的生态系统向显生宙以后生动物占主导的生态系统的转变期,埃迪卡拉纪大型软躯体生物以固着、底栖、食悬浮为特色,普遍缺乏运动能力。作为这一时期特殊代表的高家山生物群,是目前新元古代唯一一个以黄铁矿化三维保存的管状和锥管状化石为主导,兼有骨骼生物、原生动物、钙化蓝细菌类及遗迹化石的多门类生物组合,是研究埃迪卡拉纪末期生命演化和生态系统演变十分重要的载体。本文通过对高家山生物群古生态学的初步研究,揭示出在前寒武纪—寒武纪之交,生态系统已显示一定的多样性。为适应平底面上(level-bottom)微生物席的发育,高家山生物群的许多生物采取了适应性的生存策略,通过黏附或插入微生物席中,营底栖固着食悬浮(如Cloudina、Conotubus)或化学共生(可能的Shaanxilithes)或平躺(如Gaojiashania和Sinotubulites)食碎屑生活。底内遗迹化石表明存在可能的表栖和半内栖、可自由运动、食碎屑的造迹生物。Conotubus中常见的“回春”或“复苏”现象,Gaojiashania和Sinotubulites的身体扭转或生活姿态调整则是对频繁风暴事件的被动适应。 相似文献
5.
Smart card-automated fare collection systems now routinely record large volumes of data comprising the origins and destinations of travelers. Processing and analyzing these data open new opportunities in urban modeling and travel behavior research. This study seeks to develop an accurate framework for the study of urban mobility from smart card data by developing a heuristic primary location model to identify the home and work locations. The model uses journey counts as an indicator of usage regularity, visit-frequency to identify activity locations for regular commuters, and stay-time for the classification of work and home locations and activities. London is taken as a case study, and the model results were validated against survey data from the London Travel Demand Survey and volunteer survey. Results demonstrate that the proposed model is able to detect meaningful home and work places with high precision. This study offers a new and cost-effective approach to travel behavior and demand research. 相似文献
6.
面向服务的移动GIS开发与应用逐渐成为移动GIS领域研究热点和发展趋势。本文首先介绍了Android终端和UCMap开发平台等相关知识;其次详细研究了基于移动GIS应用的Android平台开发环境搭建和基于UCMap平台的Android终端应用二次开发模块;最后提出了一种基于移动GIS应用的UCMap平台开发与应用模式,并在Android平台上进行了相关技术验证,对移动GIS应用研究具有较高的技术参考价值。 相似文献
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8.
Glaciokarst is a landscape which combines karst features and hydrology as well as inherited glacial features. It is a result of glaciation upon a karst geomorphological system. The relationship between glaciers and karst is rather poorly known and inadequately recognized. This research focuses on three distinct karst areas along the Adriatic coast in the southern Dinaric Alps that were affected by the Quaternary glaciations. An insight into specific glaciokarst processes and surface features was provided through the study of the areas of the Lov?en, Orjen and Vele? Mountains. A glaciokarst geomorphology is in general well preserved due to the prevailing vertically oriented chemical denudation following de‐glaciation and almost the entire absence of other surface processes. Typical glacial erosional features are combined by a variety of depressions which are the result of a karstic drainage of sub‐glacial waters. The majority of glacial deposits occur as extensive lateral‐terminal moraine complexes, which are often dissected by smaller breach‐lobe moraines on the external side of the ridge. Those moraine complexes are likely to be a product of several glacial events, which is supported by complex depositional structures. According to the type of glacial depositional features, the glaciers in the study areas were likely to have characteristics of moraine‐dammed glaciers. Due to vertical drainage ice‐marginal fluvial processes were unable to evacuate sediment. Fluvial transport between glacial and pro‐glacial systems in karst areas is inefficient. Nevertheless, some sediment from the glacier margin is washed away by the pro‐glacial streams, filling the karst depressions and forming piedmont‐type poljes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
随着社会经济与信息技术的不断发展,地市级智慧城市建设提上日程,如何建立一套规范统一而又具有通用性的地理信息共享服务平台是其关键.平台建设必须考虑三方面内容,即建设内容、运维机制与具体应用.在智慧唐山建设过程中,以面向服务为目标,顾及地市级地理信息共享服务平台的通用性,针对总体需求、总体架构、关键技术等方面进行设计,明确地理信息共享服务平台建设的内容、运维机制建设以及示范应用等内容,探讨适用于地市级智慧城市地理信息共享服务平台构建的解决方案. 相似文献
10.