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281.
Despite the fortification of buildings, streets, and public squares, Rio de Janeiro's beaches remain widely regarded as democratic spaces of social diversity and accessibility. Our study revisits the question of Rio's “democratic” beachfronts, based on local interviews, field observations, official reports, and newspaper accounts. We focus on historical and contemporary perceptions of planning, privatization, and public-order programs on the city's southern seaside. Institutional discourses have justified increasing regulation to combat threats of disorder and insecurity. While residents value the relative openness of beachfronts, they also acknowledge issues of safety, social segmentation, and subtle forms of bias. The public generally applauds recent “Shock of Order” policing and commercial revitalization, although critics lament the loss of traditional freedoms for informal beach vendors and casual sports. These paradoxes highlight enduring tensions between social order and hierarchy on one hand, and democratic rights and equality on the other.  相似文献   
282.
The ECCO–GODAE global estimate of the ocean circulation 1992–2007 is analyzed in the region of the Indonesian Throughflow (ITF), including the Southern Ocean flow south of Australia. General characteristics are an intense month-to-month noise, only weak trends, and an important annual cycle (which is not the focus of attention). Apart from the details of the unresolved flows within the various passages, and right on the equator, the region and its large-scale climate effects appears to be accurately diagnosed by large-scale geostrophic balance, so that the ITF can be calculated either from the upstream or the downstream balanced flow (but no simple reference level can be defined). The INSTANT program occurs during a more or less typical three-year period. Indications of response to the large 1997–1998 El Niño are weak.  相似文献   
283.
Loss of life and property caused by landslides triggered by extreme rainfall events demonstrates the need for landslide-hazard assessment in developing countries where recovery from such events often exceeds the country's resources. Mapping landslide hazards in developing countries where the need for landslide-hazard mitigation is great but the resources are few is a challenging, but not intractable problem. The minimum requirements for constructing a physically based landslide-hazard map from a landslide-triggering storm, using the simple methods we discuss, are: (1) an accurate mapped landslide inventory, (2) a slope map derived from a digital elevation model (DEM) or topographic map, and (3) material strength properties of the slopes involved. Provided that the landslide distribution from a triggering event can be documented and mapped, it is often possible to glean enough topographic and geologic information from existing databases to produce a reliable map that depicts landslide hazards from an extreme event. Most areas of the world have enough topographic information to provide digital elevation models from which to construct slope maps. In the likely event that engineering properties of slope materials are not available, reasonable estimates can be made with detailed field examination by engineering geologists or geotechnical engineers. Resulting landslide hazard maps can be used as tools to guide relocation and redevelopment, or, more likely, temporary relocation efforts during severe storm events such as hurricanes/typhoons to minimize loss of life and property. We illustrate these methods in two case studies of lethal landslides in developing countries: Tegucigalpa, Honduras (during Hurricane Mitch in 1998) and the Chuuk Islands, Micronesia (during Typhoon Chata'an in 2002).  相似文献   
284.
Kiran Asher 《Geoforum》2009,40(3):292-302
In this paper, we explore how ordenamiento territorial, a territorial zoning policy in the 1991 Colombian Constitution remakes nature and helps constitute the state in the “economically backward” but “biodiversity rich” Pacific lowlands region. We draw on Gramscian insights on hegemony and the importance of conjunctures to trace how changes in the new Constitution and global biogeopolitics reconfigure nature and state power through the mandates of sustainable development, economic growth, and the conservation of biological and cultural diversity. Finally, we contribute to the literature on political ecology by showing how the political power of the state, nature, and capital are interwoven materially and symbolically in complex and contradictory ways.  相似文献   
285.
地震模拟振动台参数灵敏度分析   总被引:2,自引:0,他引:2  
以地震模拟振动台(以下简称振动台)线性模型为基础,应用一阶灵敏度模型分析了振动台三状态反馈控制参数的灵敏度函数及其对系统动态特性的影响,用仿真的方法分析了三状态反馈参数的变化对系统输出特性的影响程度。  相似文献   
286.
The expense and uncertainty of obtaining fluid samples from MDT tools provide a strong incentive for an alternative method for assessing oil character. Sidewall cores, which are inexpensive and easy to obtain, contain sufficient oil for microanalyses that can provide indications of oil quality (degree of degradation), API gravity, and numerous additional characteristics, including sulfur content, acid number, and viscosity.The present study is concerned with the application of the micro-techniques PFID (pyrolysis-flame ionization detection), TEC (thermal extraction chromatography), and NIR (near infra-red spectroscopy) for the characterization of oil from sidewall cores taken from two exploration wells in the Rio Del Rey Basin of Cameroon in 1993.  相似文献   
287.
本文在分析70年代以来美国华盛顿州港口系统开发的特征、措施及其效果基础上,总结出华盛顿州港口系统抓住亚太地区经济腾飞的良机,统一规划沿海各港口群区的地位、功能和作用,大力发展集装箱多式联运等经验,均可作为发展我国沿海港口系统的借鉴。  相似文献   
288.
本文评述了黄渤海海域污染状况和年变化趋势,以及对生态的影响。  相似文献   
289.
The Transient Gamma-Ray Spectrometer (TGRS) was launched aboard the GGS/WIND spacecraft on November 1, 1994. After several deep space orbits (2 yrs) WIND will eventually be injected into a halo orbit around the Sun-EarthL 1 point. TGRS consists of a 215 cm3 high purityn-type Ge crystal which is kept at cryogenic temperatures by a passive radiative cooler. The energy range covered by the instrument is 25–8000 keV with an energy resolution of 2–3 keV. The primary task of TGRS is to perform high resolution spectroscopy of gamma-ray bursts and solar flares. Additional objectives are the study of transient x-ray pulsars and, using an on-board passive occulter, the long-term monitoring of sources such as the Crab and the Galactic Center. Since launch, TGRS has been performing exceedingly well, and all the important experiment parameters such as background levels, gain, and resolution have proven to be very stable. To date, TGRS has detected 27 GRBs and three solar flares. Preliminary analysis of our data also indicates that TGRS is indeed sensitive to sources such as the Crab and the Galactic Center.  相似文献   
290.
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