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401.
Amit Birenboim Kristian Hegner Reinau Noam Shoval Henrik Harder 《The Professional geographer》2013,65(4):620-629
The notion of consumer and user experience has become dominant in our society in recent years, especially in relation to leisure activities. In this study we used the experience sampling method (ESM) data collection technique in Aalborg Zoo, Denmark, to understand the distribution of subjective experiences within this site. Visitors to the zoo were asked to send phone messages (SMS) about their subjective feelings in real time and to carry with them Global Positioning System (GPS) devices that recorded their movement. This method allowed us to geotag experiences of visitors throughout the zoo compound. The results indicate that the quality of experience of visitors varies both in time and in space. We conclude that there is a need to further explore the effect of place on experiences using repeat, high-resolution measurements. In this regard we believe that geographers, who have a long tradition of studying human–environment relations, have the tools to lead this type of exploration. 相似文献
402.
Direct measurements of the hydrological conditions for the occurrence of debris flows and of flow behaviour are of the outmost importance for developing effective flow prevention techniques. An automated and remotely controlled monitoring system was installed in Acquabona Creek in the Dolomites, Italian Eastern Alps, where debris flows occur every year. Its present configuration consists of three on‐site stations, located in the debris‐flow initiation area, in the lower channel and in the retention basin. The monitoring system is equipped with sensors for measuring rainfall, pore‐water pressure in the mobile channel bottom, ground vibrations, debris flow depth, total normal stress and fluid pore‐pressure at the base of the flow. Three video cameras take motion pictures of the events at the initiation zone, in the lower channel and in the deposition area. Data from the on‐site stations are radio‐transmitted to an off‐site station and stored in a host PC, from where they are telemetrically downloaded and used by the Padova University for the study of debris flows. The efficiency of the sensors and of the whole monitoring system has been verified by the analysis of data collected so far. Examples of these data are presented and briefly discussed. If implemented at the numerous debris‐flow sites in the Dolomitic Region, the technology used, derived from the development of this system, will provide civil defence and warn residents of impending debris flows. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
403.
展望大数据时代的地球空间信息学 总被引:5,自引:1,他引:4
20世纪90年代,随着全球信息化和互联网的推进,地球空间信息学应运而生,推动了数字地球和数字城市的建设。21世纪以来,随着全球信息化与工业化的高度集成发展,出现了物联网和云计算,人类进入了大数据时代。本文论述大数据时代地球空间信息学的特点(无所不在、多维动态、互联网+网络化、全自动与实时化、从感知到认知、众包与自发地理信息、面向服务)和必须解决的主要关键技术问题(全球空天地一体化的非线性地球参考框架构建技术、星基导航增强技术、天地一体化网络通信技术、多源成像数据在轨处理技术、天基信息智能终端服务技术、天基资源调度与网络安全、基于载荷的多功能卫星平台设计与研制)。本文最后给出大数据时代地球空间信息学的新定义,即地球空间信息学是用各种手段和集成各种方法对地球及地球上的实体目标(physical objects)和人类活动(human activities)进行时空数据采集、信息提取、网络管理、知识发现、空间感知认知和智能位置服务的一门多学科交叉的科学和技术。从这个新定义出发,地球空间信息学将在构建智慧地球和智慧城市的大数据时代面临更多的发展机遇和艰巨的任务,必将为人类社会的进步和可持续发展作出更大的贡献。 相似文献
404.
405.
Whether it be Smart Cities, Ambient Intelligence, or the Internet of Things, current visions for future urban spaces share a common core, namely the increasing role of distributed sensor networks and the on‐demand integration of their data to power real‐time services and analytics. Some of the greatest hurdles to implementing these visions include security risks, user privacy, scalability, the integration of heterogeneous data, and financial cost. In this work, we propose a crowdsensing mobile‐device platform that empowers citizens to collect and share information about their surrounding environment via embedded sensor technologies. This approach allows a variety of urban areas (e.g., university campuses, shopping malls, city centers, suburbs) to become equipped with a free ad‐hoc sensor network without depending on proprietary instrumentation. We present a framework, namely the GeoTracer application, as a proof‐of‐concept to conduct multiple experiments simulating use‐case scenarios on a university campus. First, we demonstrate that ambient sensors (e.g. temperature, pressure, humidity, magnetism, illuminance, and audio) can help determine a change in environment (e.g. moving from indoors to outdoors, or floor changes inside buildings) more accurately than typical positioning technologies (e.g. global navigation satellite system, Wi‐Fi, etc.). Furthermore, each of these sensors contributes a different amount of data to detecting events. for example, illuminance has the highest information gain when trying to detect changes between indoors and outdoors. Second, we show that through this platform it is possible to detect and differentiate place types on a university campus based on inferences made through ambient sensors. Lastly, we train classifiers to determine the activities that a place can afford at different times (e.g. good for studying or not, basketball courts in use or empty) based on sensor‐driven semantic signatures. 相似文献
406.
南极内陆冰盖表面的特征与冰盖表面年际降雪量、冰盖表面风速有关,冰盖表面地貌特征主要包括雪面粗糙度、雪层软硬度,这些特征对内陆车队行进过程中的设备运输具有重要的参考价值。文中提出了车载自动化监测冰盖雪面特征的方法,并进行了监测系统的设计与数据分析;该系统包括以雪地车颠簸幅度代表的雪面凹凸程度(即雪面粗糙度),以GPS模块监测车辆行进距离,以激光测距监测雪地车车辙深度来表征雪面软硬度。通过数据采集系统的实时监测软件平台,实现了冰盖表面地貌特征的监测;该系统分别于2012年11月和2014年11月在中国第29次南极和31次南极考察中进行了监测应用,通过对以上监测数据的分析,初步给出了中山站至昆仑站沿途的冰盖表面粗糙度及雪面软硬度结果。 相似文献
407.
408.
在智慧城市建设上升为国家战略的大背景下,以城市人口、经济、资源、环境等历史数据分析为基础的传统城市空间发展模型面临着数据来源与研究框架的革新。本文首先阐述了智慧城市与可持续发展理念产生的时代背景、概念内涵、相互关系,进而在梳理国内外可持续发展视角下的城市模型相关研究基础上,认为智慧城市建设为城市模型研究提供了更为精细、实时、全面的数据来源,拓宽了城市模型研究的时空尺度,并在城市系统运行模拟与仿真方面提供新的技术手段。本文从城市数据监测采集与互联共享、城市系统运行问题梳理与综合分析、城市空间发展模拟仿真与决策评估、城市空间发展规划体系4个层面尝试构建基于智慧城市的可持续城市空间发展模型总体架构,对于丰富城市可持续发展研究理论框架,指导智慧城市空间规划与建设实践具有重要意义。 相似文献
409.
R. Ahas A. Aasa Y. Yuan M. Raubal Z. Smoreda Y. Liu 《International journal of geographical information science》2015,29(11):2017-2039
This paper proposes a methodology for using mobile telephone-based sensor data for detecting spatial and temporal differences in everyday activities in cities. Mobile telephone-based sensor data has great applicability in developing urban monitoring tools and smart city solutions. The paper outlines methods for delineating indicator points of temporal events referenced as ‘midnight’, ‘morning start’, ‘midday’, and ‘duration of day’, which represent the mobile telephone usage of residents (what we call social time) rather than solar or standard time. Density maps by time quartiles were also utilized to test the versatility of this methodology and to analyze the spatial differences in cities. The methodology was tested with data from cities of Harbin (China), Paris (France), and Tallinn (Estonia). Results show that the developed methods have potential for measuring the distribution of temporal activities in cities and monitoring urban changes with georeferenced mobile phone data. 相似文献
410.