SARS空间传播模式及其在疫情监控信息系统设计中的应用

在中国控制SARS(Severe Acute Respiratory Syndrome)疫情扩散与蔓延的大量科学实践活动基础上，从人地系统科学的理论和观点出发，提出了各种致病因子在人地互动过程中转移路径的逻辑模型，进而又提出了控制SARS疫情发展的人地互动逻辑模型。从后一个模型出发，把中国SARS疫情的发展规律归纳为5种传播模式，即异类病毒转移传播模式、家庭和社区接触传播模式、医院和门诊感染传播模式、市内随机扩散传播模式和飞点跳跃跨区传播模式。其中，跨区传播模式的影响最广泛、危害最巨大、控制起来最艰巨、复杂，是建立中国突发公共卫生事件应急机制、增强应急能力需要解决的主要问题和关键内容。为此，作者对中国的疫情控制应急机制及其实现提出了一些具体的看法和建议，包括对现有疫情系统进行技术改造和创新的建议，在全新运作机制和高技术基础上建立应急疫情监测控制信息系统的概念结构等内容。     

711数字化天气雷达定标方法

对711数字化天气雷达的标定原理和方法进行了讨论，给出了雷达各项标定参数的详细标定方法。     

DEVELOPMENT OF A LOW-COST MOBILE MAPPING SYSTEM: A SOUTH AMERICAN EXPERIENCE

This paper presents the prototype of a low-cost terrestrial mobile mapping system (MMS) composed of a van, two digital video cameras, two GPS receivers, a notebook computer, and a sound frame synchronisation system. The imaging sensors are mounted as a stereo video camera on top of the vehicle together with the GPS antennae. The GPS receivers and the notebook computer are configured to record data referred to the vehicle position at a planned time interval. This position is subsequently transferred to the road images. This set of equipment and methods provide the opportunity to merge distinct techniques to make topographic maps and also to build georeferenced road image databases. Both vector maps and raster image databases, when integrated appropriately, can give spatial researchers and engineers a new technique whose application may realise better planning and analysis related to the road environment. The experimental results proved that the MMS developed at the São Paulo State University is an effective approach to inspecting road pavements, to map road marks and traffic signs, electric power poles, telephone booths, drain pipes, and many other applications important to people's safety and welfare. A small number of road images have already been captured by the prototype as a consequence of its application in distinct projects. An efficient organisation of those images and the prompt access to them justify the need for building a georeferenced image database. By expanding it, both at the hardware and software levels, it is possible for engineers to analyse the entire road environment on their office computers.     

Participatory video in geographic research: a feminist practice of looking?

This paper explores how participatory video – a methodology increasingly used in community development and anthropological research – may enable a feminist practice of looking which does not perpetuate hierarchical power relations and create voyeuristic, distanced and disembodied claims to knowledge. I reflect on experiences from a participatory video project with members of a Maaori tribe in Aotearoa New Zealand in light of geographers' uses of video to date. I argue that participatory video, if used within carefully negotiated relationships, has potential to destabilize hierarchical power relations and create spaces for transformation by providing a practice of looking 'alongside' rather than 'at' research subjects.     

数码相机实施摄像测量的几个问题

提出像方几何量均取像素为单位处理，以直接使用现有摄影测量程序并使检校过程简化，给出α值的检校要求关系式，罗列主距的锁定方式，总结数码相机所摄影像的多种处理方法并充分利用数码相机功能。     

暴雨及其衍生灾害的三维影视模拟技术初探

由于暴雨常具有和危险性,难以及时拍摄到暴雨灾害的现场画面,本文基于大气降水粒子的物理特征,采用Maya、Reanlflow、AfterEffects、Premier等软件运用刚体碰撞、流体、粒子等动画技术,对暴雨及其引发的城市积涝、山体滑坡和泥石流灾害的发生和演变过程进行影视模拟,初步建立了相关技术流程及技术指标,可用于指导气象灾害类科普影视节目的制作,宣传防灾减灾知识。     

Visualization of spatial patterns and temporal trends for aerial surveillance of illegal oil discharges in western Canadian marine waters

This paper examines the use of exploratory spatial analysis for identifying hotspots of shipping-based oil pollution in the Pacific Region of Canada’s Exclusive Economic Zone. It makes use of data collected from fiscal years 1997/1998 to 2005/2006 by the National Aerial Surveillance Program, the primary tool for monitoring and enforcing the provisions imposed by MARPOL 73/78. First, we present oil spill data as points in a “dot map” relative to coastlines, harbors and the aerial surveillance distribution. Then, we explore the intensity of oil spill events using the Quadrat Count method, and the Kernel Density Estimation methods with both fixed and adaptive bandwidths. We found that oil spill hotspots where more clearly defined using Kernel Density Estimation with an adaptive bandwidth, probably because of the “clustered” distribution of oil spill occurrences. Finally, we discuss the importance of standardizing oil spill data by controlling for surveillance effort to provide a better understanding of the distribution of illegal oil spills, and how these results can ultimately benefit a monitoring program.     

Variability of shallow overland flow velocity and soil aggregate transport observed with digital videography

Field experiments at Tiramoana station 30 km north of Christchurch, New Zealand using an erosion plot 16·5 m long, 0·6 m wide, and with a slope of 14–14·5° on rendzina soil aimed to measure the variability of flow velocity and of soil aggregates transport rate in shallow overland flow. Discharge/cross‐section area ratio was used to estimate mean velocity, and high‐speed digital video camera and image analysis provided information about flow and sediment transport variability. Six flow runs with 0·5–3·0 L s^?1 discharges were supercritical with Froude numbers close to or more than 1. Mean flow velocity followed Poiseuille law, float numbers were more than 1·5 and hydraulic resistance was an inverse proportional function of the Reynolds number, which is typical for laminar flows. Hence actual velocity varied through time significantly and the power spectrum was of ‘red‐noise’, which is typical for turbulent flow. Sediment transport rates had even higher variability, and soil aggregates transport was a compound Poisson process. Copyright © 2008 John Wiley & Sons, Ltd.     

Quantifying the temporal dynamics of wood in large rivers: field trials of wood surveying,dating, tracking,and monitoring techniques

Wood plays an important role in stream ecology and geomorphology. Previous studies of wood in rivers have quantified spatial distributions but temporal dynamics remain poorly documented. The lack of such data is related to limitations of existing methods, especially when applied to large rivers. Five techniques are field‐tested to assess their utility for quantifying the temporal dynamics in rivers: repeated high‐resolution aerial surveys, the measurement of wood physical characteristics as proxies for ¹⁴C dating, passive and active radio frequency identification (RFID) tags, radio transmitters, and video. The spatial distribution of wood is surveyed using aerial imagery with a resolution finer than 0·10 m. The estimation of temporal trends by repeated aerial‐based surveys needs to consider vegetation growth and hiding. Wood residence times can be calculated using ¹⁴C analysis, but the assessment of wood physical characteristics including decay status and wood density offers a cheaper, if less accurate, alternative. Wood resistance to penetration is tested but results are not significant. Radio transmitters are reliable for multi‐year (～5 year) surveys and can be detected at 800 m. Passive RFID tags are limited by a read range of 0·30 m but are reliable for longer term (>5 year) studies. Active RFID tags combine a moderate read range (10–300 m) and low cost with in‐flood detection but require more testing. Video monitoring of wood passing on the surface of a river is successfully implemented. For a single flood on the Ain River (France), wood transport rates are an order of magnitude higher on the rising limb of the hydrograph than on the falling limb. Overall, the techniques improve the ability to gather the data needed to understand wood transfer processes and calibrate budgets of wood in rivers. Copyright © 2009 John Wiley & Sons, Ltd.