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961.
Tsunami education activities, materials, and programs are recognized by the National Tsunami Hazard Mitigation Program (NTHMP) as the essential tool for near-source tsunami mitigation. Prior to the NTHMP, there were no state tsunami education programs outside of Hawaii and few earthquake education materials included tsunami hazards. In the first year of the NTHMP, a Strategic Plan was developed providing the framework for mitigation projects in the program. The Strategic Plan identifies education as the first of five mitigation strategic planning areas and targets a number of user groups, including schools, businesses, tourists, seasonal workers, planners, government officials, and the general public. In the 6 years of the NTHMP tsunami education programs have been developed in all five Pacific States and include print, electronic and video/film products, curriculum, signage, fairs and workshops, and public service announcements. Multi-state education projects supported by the NTHMP include TsuInfo, a bi-monthly newsletter, and Surviving a Tsunami, a booklet illustrating lessons from the 1960 Chilean tsunami. An additional education component is provided by the Public Affairs Working Group (PAWG) that promotes media coverage of tsunamis and the NTHMP. Assessment surveys conducted in Oregon, Washington, and Northern California show an increase in tsunami awareness and recognition of tsunami hazards among the general population since the NTHMP inception.  相似文献   
962.
This paper analyses local level apprenticeship contracts and networks to highlight informal urban livelihoods within the context of socio-economic vulnerability and wider contemporary changes taking place in Koforidua, Ghana. It does so by specifically examining the complex entanglements of interpersonal relationships that characterize apprenticeship contracts within which home-based entrepreneurs and artisans in Koforidua engage in to sustain both current livelihoods, as well as to shore themselves against socio-economic vulnerability triggered in part by adjustment. As a result of the changing geography of the city, network entanglements, comprising resilient ties and egalitarian relations, have become vital to urban livelihoods in this community. However, apprenticeship contracts and the networks they engender can be a double-edged sword. For instance, demands of reciprocity or support from co-network members, neighbours and family, can be so taxing that some individuals opt out of the network. This tension notwithstanding, this paper contends that apprenticeship contracts and the network spaces they create have created a new social cohesion and community that transcend the traditionally known spaces of social support, i.e. ethnic ties, family ties or even institutional support.  相似文献   
963.
A detailed photochemical box model was used to investigate the key reaction pathways between OH, HO2 and RO2 radicals during the summer and winter PUMA field campaigns in the urban city-centre of Birmingham in the UK. The model employed the most recent version of the Master Chemical Mechanism and was constrained to 15-minute average measurements of long-lived species determined in situ at the site. The results showed that in the summer, OH initiation was dominated by the reactions of ozone with alkenes, nitrous acid (HONO) photolysis and the reaction of excited oxygen atoms atoms with water. In the winter, ozone+alkene reactions were the primary initiation route, with a minor contribution from HONO photolysis. Photolysis of aldehydes was the main initiation route for HO2, in both summer and winter. RO2 initiation was dominated by the photolysis of aldehydes in the summer with a smaller contribution from ozone+alkenes, a situation that was reversed in the winter. At night, ozone+alkene reactions were the main radical source. Termination, under all conditions, primarily involved reactions with NO (OH) and NO2 (OH and RCO3). These results demonstrate the importance of ozone+alkene reactions in urban atmospheres, particularly when photolysis reactions were less important during winter and at nighttime. The implications for urban atmospheric chemistry are discussed.  相似文献   
964.
The deterioration of air quality is threatening the life and health of people. Scientists in China and other countries have done a great deal of research work on the details of air pollution and the methods of preven-tion and control during the past decades. Up to now, most of the achievements are concentrated on the techniques of controlling pollutant sources and the programs of reduction, which focus on the improve-ment of air quality and the restoration of environment. The techniques of con…  相似文献   
965.
Spatial variation in the importance of determinants of participation in the Aid to Families with Dependent Children program (AFDC) is investigated for the U.S. Casetti's Expansion Method is applied to the two-dimensional space domain by making the model's parameters a function of state x–y centroids. The spatially-varying parameter model suggests that the black population's association with participation is lowest in the Southeast and Northwest and greatest in the Southwest and Northeast.  相似文献   
966.
锦屏电站坝厂区卸荷岩体力学参数研究   总被引:4,自引:0,他引:4  
选择具有代表性的区块,根据结构面的性状和规模拟定模型层次和尺寸,建立岩体数值仿真模型,通过计算机数值仿真,采用卸荷非线性力学理论对锦屏电站坝厂区岩体进行卸荷岩体宏观力学特性及参数的数值分析;同时,用RMR法和BP神经网络法对岩体宏观力学特性及参数进行分析,综合确定岩体力学参数,为设计部门提供设计参考依据.  相似文献   
967.
淮海经济区城市竞争力定量评析   总被引:13,自引:1,他引:12  
文章首先构建用来测度淮海经济区城市竞争力的指标体系,接着运用因子分析方法,对淮海经济区17个样本城市的竞争力进行计算,求出各城市的竞争力综合得分;然后通过聚类分析将17个样本城市的竞争力划分为强、较强、较弱、弱4类并相应地做出评价。其主要结论为:(1)大多数城市的竞争力得分值偏低;(2)各城市之间的竞争力得分有较大差距,徐州城市竞争力得分最高,排名前5位的徐州、临沂、枣庄、济宁、泰安与其后诸城市差距甚大。  相似文献   
968.
用基于Givens变换的QR分解计算类GPS广播星历参数   总被引:5,自引:0,他引:5  
分析研究类GPS广播星历参数拟合算法的必要性,来介绍可用于解最小二乘问题的Givens变换,讨论使用Givens变换计算MEO和小倾角GEO卫星的类GPS广播星历参数的适用性,并用模拟数据进行验证。  相似文献   
969.
党青  杨武年 《测绘科学》2012,37(5):138-140
土地资源对社会主义市场经济的影响显著,而土地的价格是调节土地资源优化配置的重要杠杆,及时准确公开地掌握城市土地价格的动态变化备受关注。本文探讨了动态监测系统建立的方法、地价区段监测点的选择、地价区段的划分,尝试采用克里金插值模型来实现地价区段的划分,并获得了良好的划分结果。系统采用SuperMap开发控件的WebGIS技术、基于B/S结构的分布式网络平台,通过对数据库系统的建设实现了城市地价的计算机管理和信息的定期发布。  相似文献   
970.
本文根据选权拟合法的一个重要性质:只要被约束的那部分参数估值无偏,其余的参数估值也无偏;该性质说明利用选权拟合进行参数估计的结果是条件无偏的。这个不同于一般正则化解的重要特性可以建立单历元伪距和载波相位双差模型,并通过实例验证了该方法的可行性。  相似文献   
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