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121.
Home‐based neighbourhood stores (locally known in the Philippines as sari‐sari stores) are a ubiquitous feature of most Philippine communities. They are small to medium‐size trade stores not unlike convenience stores in the West where people buy goods in small quantities. In the Philippines, these stores play a vital role in providing everyday economic sustenance to low‐income communities. But more than an economic hub, sari‐sari stores also function as a social hub that connects people and acts as eyes and ears of the community through the people who make use of their services. In a sense, sari‐sari stores are the community's ‘myopticon’ where people's day‐to‐day dealings with everyone in the community and its environs are reported and discursively brought under the gaze of the ‘entire community’. Being myopticon as opposed to Foucault's panopticon, surveillance in sari‐sari stores is partial, non‐hierarchicalized and could be resisted by people in the community. Nonetheless, regardless of the ‘myoptic’ features of sari‐sari stores, their presence in the community ‘interpellates’ everyone's daily existence and instantiates a discursive space from which a structure of informal social control is enacted among community members. Sari‐sari stores then are an important reminder of how our built environment is also about contestation and negotiation of everyday life as we make use of space and as the architectonics of space both constrain and empower our manoeuvring in places.  相似文献   
122.
The ‘less‐is‐more’ concept in interface design for computer applications has recently gained ground. In this article, the concept is adopted for a user‐centered design of geovisualization application. The premise is that using simple and clear design can lead to successful applications with improved ease of use. Over the last three decades, the development of GIS and geovisualization has seen a marked increase in the levels of interaction between the user, the system and the information. However, these enthusiastic advances in technology have not resulted in a significant increase in the number of users.

This article suggests that types of user interaction should not simply emphasize traditional GIS functions such as zooming and panning but move towards interaction based on facilitating the knowledge construction process. Considerations are made for the complexity of the system, the task at hand and the skills and limitations of the users. These elements are particularly important when maps act as the mediators in collaboration with users across disciplinary backgrounds. In such cases, the emphasis on simplicity and usability becomes as important as functionality. In these situations a geovisualization application designed for specific uses can maximize effective development of geographic knowledge.

In this article, a minimalistic design approach to geovisualization is adopted by creating a geographic profiling tool which shifts the emphasis from technological advances or interaction with the map to the interaction elements key to building the spatial knowledge of GIS experts and non‐experts alike. To evaluate this notion of ‘less‐is‐more geovisualization’ the profiling tool is evaluated according to usability matrices: efficiency, effectiveness and learnability. How well the Suburban Profiler contributes to these elements is assessed by conducting a video analysis of the types and forms of user interaction available. The video analysis demonstrates the usefulness and usability of the Suburban Profiler, providing proof of concept for ‘less‐is‐more geovisualization’.  相似文献   
123.
GW112AD型水下监视系统是携带方便、结构新颖、功能齐全和图像清晰的一款水下监视装置,通过对三号地井下环境进行检查发现,井管腐蚀老化,淤泥堵塞现象较严重,对水位变化影响较大,三号地水位多次突降异常的信度一般,需对该井进行必要的洗井清理工作.  相似文献   
124.
地理立体视频是对视频帧扩展了内外方位元素等地理空间参照的立体视频,支持基于位置的视频查询和影像量测,提供了地理空间表达的一种新形式。随着Web服务技术的广泛应用,地理立体视频Web服务将进一步拓展视频GIS应用。本文重点讨论了地理立体视频Web服务原理和系统设计。通过分析服务功能,设计了由数据层、服务层及表现层构成的地理立体视频Web服务框架;利用REST风格的Web服务技术,从资源确定、URI定义,以及资源操作接口、表述格式等方面进行了服务设计,详细定义了检索服务、视频播放服务,以及影像量测服务接口及其HTTP交互机制,以WCF框架和ArcGIS Server平台实现了相应的服务接口。本文以河南大学金明校区为例,开发了地理立体视频Web服务原型系统并进行了应用实验。结果表明,地理立体视频Web服务实现了可视化、检索及量测等功能,适合于Web环境下视频GIS应用开发,对新型可定位多媒体Web服务的标准化具有参考价值。  相似文献   
125.
The transport of wood in rivers during floods is an important process that underlies differences in habitat and morphology between water courses and regions. Quantitative data are needed to properly address management objectives and balance wood budgets. In this study we use a streamside video camera to detect wood passage and measure quasi‐instantaneous rates of wood transport in the Ain River, France. The objectives are to verify the procedure, describe the relation between wood transport and discharge, and construct and validate a wood budget for the reach upstream of the camera. Verification of the procedure includes tests of detection frequency, wood velocity, and piece size. A log base two transformation is proposed to classify wood by piece length. It was found that a wood transport threshold occurs at approximately two thirds of the bankfull discharge. Wood transport follows a positive linear relation with discharge up to the bankfull discharge but is both more variable and less sensitive to discharge when the floodplain is inundated. Transport rates are approximately four times higher on the rising limb of the hydrograph than on the falling limb. Wood transport estimates from a three‐stage rating curve are two to 10 times higher than those from a wood budget using local and aerial surveys of upstream dynamics. Future work should address uncertainties related to wood diameter measurements, sampling length and frequency, and antecedent floods. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
126.
通过对地震声像科普作品的统计分析,提出了作品中画面、音乐、字幕、图示及动画等方面主要存在的问题和不足之处,对今后如何制作好这类作品提出了建议。  相似文献   
127.
运动视频序列影像的自动配准   总被引:1,自引:1,他引:0  
影像配准是运动视频处理应用中的关键技术,从计算机视觉角度出发提出了一种针对运动视频处理的自动影像配准方法.其主要思路可以归结为基于特征匹配的配准过程,具体分为3个方面:利用Harris算子检测角点特征;以互相关函数为测度对角点特征进行初步匹配,特别使用RANSAC拟合基础矩阵F的方法剔除匹配中的错误对应;利用得到的结果重新拟合配准模型进行重采样变换.最后进一步分析了此方法应用于具体运动视频处理时需要考虑的一些问题.  相似文献   
128.
提出了一种基于小波变换的视频GIS数据水印算法。该算法结合视频GIS数据特点,将视频流分割为时间轴上连续图像序列。实验结果表明,该算法具有较好的隐蔽性与鲁棒性,并能有效抵抗帧删除、重编码等攻击。  相似文献   
129.
气象影视资料数字化归档管理系统设计与开发   总被引:1,自引:0,他引:1       下载免费PDF全文
根据影视资料量大、内容丰富的特点,采用分层式视频资料编目结构,建立气象影视资料数据库,并结合影视素材使用需求,开发了气象影视资料数字化归档管理系统,此系统可以提高气象影视资料的检索速度和影视制作的整体运行效率,并弥补气象影视资料数字化管理的空白。  相似文献   
130.
根据试验视频确定石灰岩中的位移场   总被引:2,自引:0,他引:2       下载免费PDF全文
根据室内石灰岩抗压强度试验拍摄得到的彩色视频图像与试验数据,使用数字图像相关分析技术,在对原始彩色视频图像进行可读格式转换、灰度变换、傅里叶变换基础上,利用最大相关匹配技术与小变形假设实现了石灰岩视频图像中不同位置相对位移的计算,通过循环计算得到整个石灰岩试样中的位移场与试样中各点位置的变化过程。本文方法对分析岩石变形和破坏机理具有一定的参考价值。  相似文献   
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