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41.
计算技术的发展需要与之相适应的计算模式。经过几十年的发展,计算范式经历了三次转变:中心式计算、分布式计算和移动式计算,并向普适计算迈进。不同的计算范式孕育了不同的制图模式,地图制图模式也经历了三次转变:单机版的计算机地图制图、网络地图制图和移动地图制图,并向普适地图制图的模式改变。普适地图制图是普适计算技术在地图制图领域的应用,是普适计算与地图制图相结合的产物,它的出现给地图制图带来了一场新的革命。在分析国内外相关文献的基础上,阐述了普适地图制图的概念,重点介绍了普适地图制图的主要研究内容和关键技术,为今后普适地图制图的研究提供了一定的指导意义,具有较好的参考价值。  相似文献   
42.
With the widespread use of tag clouds, multiple map-based variations have been proposed. Like standard tag clouds (also called word clouds), these ‘tag maps’ all share the basic strategy of displaying words within a ‘geographic space’ and scaling the word size to depict frequency (or importance) of those words within some dataset. While some tag maps simply plot a standard tag cloud on top of a map, the subset of tag maps we focus on here are those in which the collection of words are displayed within bounded geographic regions (often of irregular shape) that the words are relevant for. For this form of tag map, map scale and polygon shape add constraints to word size and position that have not been considered in most prior approaches to tag map word layout. In this paper, we present a layout strategy for tag map generation that includes consideration of the shape and size of the geographical regions acting as containers for the tags. The method introduced here uses a triangulated irregular network (TIN) to subdivide the geographical region into many triangle subareas, with the centroid of each triangle being a potential location to centre a tag on. All the triangles are sorted by their area and all the tags are sorted by their weight value (e.g. frequency, importance or popularity). Positioning of tags is undertaken sequentially from most important (or frequent or popular) with potential locations being the TIN triangle centroids (tried from largest to smallest triangle). After each tag placement, the TIN is recalculated to integrate the tag centroid and bounding corners into the TIN creation. The limited whitespace in the geographical region, at any specific scale, is used fully by dynamically adjusting the font size along with the number and the direction of tags. The method can be applied to add tags within geographic polygons that are convex, concave and other more complex regions containing holes or islands.  相似文献   
43.
克孜尔塔格岩体侵入最新地层为下石炭统干墩岩组.该岩体中剪切变形的花岗闪长岩锆石SHRIMP U-Pb定年为271.6Ma±1.6Ma,此年龄值介于王瑜等所研究剪切作用的年龄276~254Ma之间,岩体侵位时代应略早于变形时代,为晚石炭世末至早二叠世早期,271.6Ma为岩体结晶年龄,时代为早二叠世晚期.  相似文献   
44.
This paper reports a radiofrequency identification (RFID) tracing experiment implemented in a high‐sediment‐load mountain stream typical of alpine gravel‐bed torrents. The study site is the Bouinenc Torrent, a tributary to the Bléone River in southeast France that drains a 38·9‐km² degraded catchment. In spring 2008, we deployed 451 tracers with b‐axis ranging from 23 to 520 mm. Tracers were seeded along eight cross‐sections located in the upstream part of the lowest 2·3 km of the stream. Three tracer inventories were implemented in July 2008, 2009 and 2010. Recovery rates calculated for mobile tracers declined from 78% in 2008 to 45% in 2009 and 25% in 2010. Observations of tracer displacement revealed very high sediment dispersion, with frontrunners having travelled more than 2 km only three months after their deployment. The declining recovery rate over time was interpreted as resulting from rapid dispersion rather than deep burial. We evaluated that 64% of the tracers deployed in the active channel were exported from the 2·3‐km study reach three years after the onset of the tracing experiment. Travel distances were characterized by right‐skewed and heavy‐tailed distributions, correctly fitted by a power‐law function. This supports the idea that in gravel‐bed rivers with abundant sediment supply relative to transport capacity, bedload transport can be viewed as a superdiffusive sediment dispersion process. It is also shown that tracers initially deployed in the low‐flow channel were characterized by a 15‐ to 30‐fold increase of mobility compared to tracers deployed in gravel bars. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
45.
当今,电子商务的时代已经到来。电子商务给全球物流带来了新的发展,数字物流成为货物全球化生产、网络化配销的一项重要增值服务。将射频识别技术(RFID)与地理信息系统(GIS)等技术集成应用于物流系统,能形成一个对车辆和货物信息进行实时监管的立体识别定位安全网络,这是任何其他技术所无法企及的。本文考虑了车辆和货物进入隧道和车库时,GPS设备接收不到卫星信号而无法进行定位的情况,提出了GPS与基站混合定位的物流商品监控系统模型。该系统模型采用RFID技术对物流车辆和货物进行动态的识别和数据信息交换,采用北京超图软件股份有限公司提供的SuperMap Objects组件实现车辆和货物的实时监控、信息动态追踪、轨迹回放、信息管理等功能。文中给出该系统模型的实现机理,并对其进行了分析和评价。该模型的提出为物流运作的实时监控研究贡献了一种新的解决方案。  相似文献   
46.
Understanding coarse sediment transport is crucial for the prediction of sediment migration and the consequent development of fluvial morphologies. In this study, cobble displacements in a pre-Alpine creek have been recorded by means of radio frequency identification (RFID). Pebble monitoring has been systematically performed after each rainfall event with moderate precipitation, in order to exclude the superimposition of sediment displacements induced by triggering factors acting at different times. The analysis of the collected data was carried out through the application of both a principal component analysis and the Buckingham Π theorem. The experimental trends were interpreted considering the ratio of mobile pebbles, the pebbles' displacement and virtual velocity as the dependent variables. These quantities mostly depend on the event peak discharge, with a nonlinear increase of the travelled distance and a growth of up to two orders of magnitude of the virtual velocity (for an approximately 10× increase in peak discharge). An inverse dependency of the virtual velocity on the event duration was also observed. A comparison of the results obtained with those from laboratory investigations of bedload transport mechanics evidenced the differences in parametric trends associated with sediment mobility in the two environments. This contrast brings forward the combination of multiple drivers of sediment mobility, such as local morphology, sediment dimensions and flow unsteadiness, warranting a further in-depth investigation. Representation of results in a dimensionless form is suggested as a good practice to analyse data from case studies characterized by different scales. © 2019 John Wiley & Sons, Ltd.  相似文献   
47.
马蕾  方睿  张琨 《气象科技》2014,42(3):423-427
为了优化气象装备的管理效率和保障能力,加强气象装备应急储备管理,提出一种基于RFID(Radio Frequency Identification)技术、手持设备和Web开发相结合的气象装备全寿命跟踪系统平台。该系统根据气象装备在全国范围内的调配和仓储等业务需求,实现全国气象装备管理一体化和业务统一化,为装备的管理及有效利用提供了方便;通过跟踪气象装备的状态信息(包括仓储信息、基本设备信息、业务状态等),为装备管理提供了更加详细的参考依据。结合气象装备编码规则的研究成果,为每个气象设备进行唯一标识,同时也为气象装备寿命的预测提供了实际参考数据。  相似文献   
48.
以 6 -氨基喹啉 - N-羟基琥珀酰亚胺基氨基甲酸酯 (AQC)为衍生剂 ,与毛蚶抗贫血口服液中的氨基酸柱前定量衍生 ,用 Waters HPL C仪 ,Acc Q- Tag TM专用 C18柱 (3.9mm× 15 cm) ,以140 mmol· L-1的醋酸钠溶液 (p H5 .0 2 )为溶剂 A,乙腈为溶剂 B,超纯水 (Milli- Q水 )为溶剂 C,进行梯度洗脱 ,检测波长为 2 4 8nm,35 min测试完毕。各种氨基酸测定的重现性 RSD%均 <3.0 %(n=5 )。该方法简便快速 ,结果准确可信。  相似文献   
49.
叙述了传统食堂售饭系统的不足,介绍了CAN总线与非接触式IC卡技术的特点和优势,并对以这两种技术为基础的新型食堂售饭系统窗口机的软硬件设计原理进行了较详细的分析。窗口机硬件系统主要由CAN总线通信接口、IC卡读写器、键盘、显示和存储器等功能模块组成,软件系统主要由窗口机初始化模块、窗口机监控模块、窗口机按键处理模块等组成。论文在对窗口机原理进行分析的同时,也对设计中遇到的关键问题进行了讨论,对于今后食堂售饭系统的设计提供了一个新的思路。  相似文献   
50.
韩军  颜龙 《地震工程学报》2015,37(3):896-900
动物异常是地震宏观测报的一个重要手段,本研究旨在帮助科研人员建立起长期的动物生活习性信息管理系统,方便其对动物生活习性信息的收集和研究。通过为每一只宏观观测动物配置ID卡,利用LabVIEW提供的串口配置函数和LabSQL工具包,上位机在Access数据库中调取每个ID所对应的动物日常生活习性信息,实现对动物信息表的查看、特定动物信息查询以及动物信息录入等功能。为科研人员掌握宏观观测动物生活习性,辨别动物震兆异常行为提供依据。  相似文献   
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