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961.
Benedikt Halldórsson Símon Ólafsson Ragnar Sigbjörnsson 《Journal of Earthquake Engineering》2013,17(3):343-370
The two Mw 6.5 earthquakes on June 17 and 21, 2000, respectively, in the populated South Iceland Seismic Zone (SISZ) significantly augmented the Icelandic database of strong ground motions, and several strong velocity pulses were recorded at near-fault sites. The strong motions are interpreted via the Specific Barrier Model (SBM) and a mathematical model of near-fault velocity pulses. The data indicates self-similar source scaling and significantly greater attenuation of seismic waves than in other interplate regions. Through inversion of the data a new attenuation function for the SISZ has been adopted, which results in unbiased simulations. For the first time, the characteristics of the recorded near-fault pulses have been identified and compared to the worldwide database of such records. The SBM and the near-fault pulse model combine naturally in a fast and efficient synthesis of realistic, broad-band strong ground motions in the far-fault and near-fault region. Such simulations are showcased for the June 2000 earthquakes and indicate that the modeling approach adopted in this study is an effective tool for the estimation of realistic earthquake ground motions in the SISZ. 相似文献
962.
In this paper, a methodology is suggested and tested for evaluating the relative performance of conventional and adaptive pushover methods for seismic response assessment. The basis of the evaluation procedure is a quantitative measure for the difference in response between these methods and inelastic dynamic analysis which is deemed to be the most accurate. Various structural levels of evaluation and different incremental representations for dynamic analysis are also suggested. This method is applied on a set of eight different reinforced concrete structural systems subjected to various strong motion records. Sample results are presented and discussed while the full results are presented alongside conclusions and recommendations, in a companion paper. 相似文献
963.
In order better to interpret the chemical composition of ancient organic residues and artefacts containing beeswax, the degradation of this raw material was accelerated in the laboratory by controlled heating. During the course of degradation, deposits were condensed above the beeswax. Both degraded beeswax and these deposits were analysed. These experiments definitively proved that n‐alkane depletion is due to a sublimation process that depends on the molecular weight of these hydrocarbons. The formation of benzoic and cinnamic derivatives due to the degradation of flavonoid precursors initially present in beeswax has also been highlighted for the first time. The analysis of samples from Neolithic and Roman periods led to the identification of beeswax characterized by different degradation patterns linked to their environmental context. 相似文献
964.
Local Government Portfolios and Regional Growth: Some Combined Dynamic CGE/Optimal Control Results 总被引:1,自引:0,他引:1
A theoretical policy model is presented that combines regional dynamic CGE modeling and optimal control to explore the role of local government taxation and expenditure in enhancing regional growth. It contributes to the regional CGE literature by explicitly solving for an optimal policy and augments earlier regional optimal control models by adding endogenous optimization of producer and consumer agents in response to endogenously determined prices. Results of three policy regimes are analyzed in terms of gains in the objective function, impacts on income inequality, and sensitivity to model parameterization. 相似文献
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966.
967.
The pursuit of "coordination" has been a prominent theme both in local responses to homelessness and in the current incentives in federal housing policy. This article reviews some of the conditions that make coordination important yet difficult to achieve in the homeless area. A variety of approaches for achieving coordination at the local level are reviewed, ranging from point-of-service coordination to system-design. The local examples are drawn from the cities participating in the evaluation of The Robert Wood Johnson and the Department of Housing and Urban Development Homeless Families Program. The questions of effectiveness and future prospects for homeless service coordination are raised. 相似文献
968.
R. Macchiarelli L. Bondioli S. Caropreso A. Mazurier G. Merceron E. L. Piana 《International Journal of Osteoarchaeology》2006,16(4):328-337
The biohistory of the human peopling of the Fuegian Archipelago and the processes of biocultural adaptation and microdifferentiation of the ethnohistorical ‘canoe’ (‘sea nomad’) and ‘foot’ natives are poorly known. Here we report the oldest human remains of a ‘sea nomad’ native discovered so far in the Beagle Channel region. The specimen consists of a deciduous molar from the site of Imiwaia I, dated to 5870 ± 145 years BP. The microwear pattern indicates the consumption of hard food processed by long chewing cycles. The histomorphometric analysis shows the presence of at least three episodes of stress between 8 and 10.5 months after birth, and an unusually thin neonatal line, suggesting a mechanically non‐stressing birth event. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
969.
S. Homes Hogue 《International Journal of Osteoarchaeology》2006,16(3):236-248
Analysis of a bundle burial of a young male recovered from 22OK905, a late prehistoric/protohistoric site located near Starkville, Mississippi, is discussed. AMS dating of the burial places it between AD 1640 and AD 1814, a time when Native American and European conflicts are well documented. One interesting finding is the presence of cut marks on the frontal bone of this individual. These marks were determined to be the result of scalping rather than defleshing marks associated with secondary burial treatment. Comparisons of bone element frequency among several bundle burials suggest that this individual died away from his village and the body was later collected for burial. A second study indicates that a stone tool may have been used to scalp the victim. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
970.
The skeletal remains of a child aged 2.5–3.5 years, recovered during archaeological excavations at the churchyard of St Martin's Church, Birmingham, UK, were examined using gross observation, radiography and scanning electron microscopy. Lesions suggestive of the presence of rickets and of secondary hyperparathyroidism were found. This appears to be a first report of secondary hyperparathyroidism in response to rickets in a palaeopathological specimen. The potential of microscopic examination of bone for interpreting disease processes is emphasised. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献