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171.
D. K. Yoon 《Natural Hazards》2012,63(2):823-843
The purpose of this study is to examine and compare the methodologies being developed in assessing social vulnerability to natural disasters. Existing vulnerability literature shows that two methods have been used in developing social vulnerability indexes: (1) a deductive approach based on a theoretical understanding of relationships and (2) an inductive approach based on statistical relationships (Adger et al. in New indicators of vulnerability and adaptive capacity. Tyndall Centre for Climate Change Research, Norwich, 2004). Two techniques were also utilized in aggregating social vulnerability indicators: (1) a deductive approach using standardization techniques such as z scores or linear scaling (Wu et al. in Clim Res 22:255?C270, 2002; Chakraborty et al. in Nat Hazards Rev 6(1):23?C33, 2005) and (2) an inductive approach using data-reduction techniques such as factor analysis (Clark et al. in Mitig Adapt Strateg Glob Change 3(1):59?C82, 1998; Cutter et al. Soc Sci Quart 84(2):242?C261, 2003). This study empirically compares deductive and inductive index development and indicator aggregation methods in assessing social vulnerability to natural disasters in the Gulf of Mexico and Atlantic coastal areas. The aggregated social vulnerability index is used to examine a relationship with disaster losses in the Gulf of Mexico and Atlantic coastal areas. The results show that coastal counties with more vulnerability in terms of social achieved status are positively associated with disaster damages, while variations in the development of the index using deductive and inductive measurement approaches produce different outcomes.  相似文献   
172.
The lithium concentration of the dissolved load from the Lena River, together with major element chemistry and GIS-based area and runoff data demonstrate the importance of evaporites in controlling dissolved Li in river waters. Eighty-four percent of the Li in the dissolved load of upper Lena tributaries comes from evaporites in these drainage basins. Altogether, at least ~20% of the total Li flux of the Lena River originates from this source. This finding has important implications for using lithium as a proxy for silicate weathering. The Li flux and the 87Sr/86Sr ratio are compared in order to address a difference between the two silicate weathering rate proxies. The proposed controls on the dissolved δ7Li values in rivers (kinetic vs. equilibrium isotopic fractionation; Rayleigh-type preferential extraction of the heavy isotope) (Huh et al., Earth Planet Sci Lett 194:189–199, 2001) are evaluated using data from both the Siberian rivers and the Orinoco River. Neither of the proposed mechanisms satisfactorily explains the comprehensive data set. Instead, a ‘mineralogy-specific view’ that emphasizes the difference in the secondary mineralogy (i.e., fractionation factor) is presented as a potential rationalization in the form of the refined Rayleigh-type extraction.  相似文献   
173.
The CLIVAR C20C project: selected twentieth century climate events   总被引:3,自引:1,他引:2  
We use a simple methodology to test whether a set of atmospheric climate models with prescribed radiative forcings and ocean surface conditions can reproduce twentieth century climate variability. Globally, rapid land surface warming since the 1970s is reproduced by some models but others warm too slowly. In the tropics, air-sea coupling allows models to reproduce the Southern Oscillation but its strength varies between models. We find a strong relationship between the Southern Oscillation in global temperature and the rate of global warming, which could in principle be used to identify models with realistic climate sensitivity. This relationship and a weak response to ENSO suggests weak sensitivity to changes in sea surface temperature in some of the models used here. In the tropics, most models reproduce part of the observed Sahel drought. In the extratropics, models do not reproduce the observed increase in the North Atlantic Oscillation in response to forcings, through internal variability, or as a combination of both.  相似文献   
174.
Extreme rainfall events recently occurring in Korea have been shown to change frequency-based rainfall amounts quite significantly. Regardless of the reason for these extremes, the general concern of most hydrologists is how to handle these events for practical applications in Hydrology. Our study aim is to evaluate these extremes with their effect on frequency-based rainfall amounts, especially if they can be assumed to be within normal levels. As there is no commonly accepted methodology to be applied to this kind of study, we follow simplified steps such as: (1) estimation of the climatological variance of frequency-based rainfall amounts, (2) estimation of confidence intervals of frequency-based rainfall amounts (lower and upper bounds for the 5 and 1% significance levels estimated using the climatological variance), and (3) evaluation of the effect of extra rainfall events on the frequency-based rainfall amounts. Twelve stations on the Korean peninsula are selected as they have relatively longer data length. The annual maximum rainfall data collected from 1954 to 1998 are used. From this study we concluded that (1) at least 30 years of data length should be used for the frequency analysis in order to assure the stability of the variance of frequency-based rainfall amounts, (2) the climatological variances estimated all range from 5 to 8% of the frequency-based rainfall amounts, and (3) even though the frequency-based rainfall amount seems to become extreme with seemingly abnormal events, it still remains under its upper bound for the 5 or 1% significance levels estimated using the climatological variance, as well as it decays exponentially to the normal level as extra events are added. Thus, we conclude that we do not need to panic over seemingly abnormal events occurring so far, but just need to consider the variability inherent in frequency-based rainfall amounts.  相似文献   
175.
In this study, genetic algorithms are applied to design controllers for the wind‐excited vibration reduction of a 76‐story tall building in the second‐generation benchmark problem. Design criteria and constraints including the comfort requirement for building occupants and the control robustness are directly incorporated in the formulation and evaluation of the fitness and penalty function of the genetic algorithm‐based control design. The method is efficient in obtaining optimal design with multiple constraint conditions. Two controllers are designed with realistic constraints and different robustness criteria. The corresponding results are investigated and compared with LQG optimal control results. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
176.
Hong-key Yoon 《GeoJournal》1994,33(4):471-477
The French Renaissance gardens and Japanese hill gardens have constrasting garden landscapes. Japanese gardens are naturalistic and intend to give illusions that they are the beautiful spots of unspoilt nature. In contrast, the appearances of French gardens are not an imitation of nature but boldly reorganised landscapes in geometric forms. These two contrasting types of garden landscapes represent two different sets of geomentalities (frames of mind regarding geographical environment).An earlier draft of this paper was presented at the Ninth New Zealand International Conference on Asian Studies, Hamilton, 23–26 August 1991. Its abridged version is published in D. Bing and K. Henshell (ed.)Japanese Perceptions of Nature and the Natural Order (Hamilton, NZ 1992), pp. 1–11. The present paper was developed from the first half of the conference paper, and was completed during my three month's tenure in 1993 as a Japan Foundation fellow. I am grateful to the Japan Foundation for their generous support of my research on the Japanese geomentality.  相似文献   
177.
Hong-key Yoon Dr. 《GeoJournal》1990,21(1-2):95-102
China's loessland is the home of ancient China's civilisation. For thousands of years, a distinct form of dwelling in Shaanxi, a part of China's loessland has been caves burrowed out of the soil. People still prefer living in cave dwellings to free standing Chinese houses. The persistence of cave dwellings may be an indication that the traditional cave dwellings has been a successful ecological adaptation to the local loess environment with long severe winters and intense summer heat.  相似文献   
178.
Book Review     
Hong-key Yoon 《GeoJournal》1992,26(2):210-112
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