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Kiralkizi Dam, a 120 m high earthfill dam located in Diyarbakir city, Turkey, was shaken by a moment magnitude, M w =4.6 earthquake at an epicentral distance of 8 km, on December 24, 2000, at 13:31 local time. The seismic response of the dam was assessed by using spectral ratios between (i) available crest and foundation records (C/F), (ii) horizontal and vertical components of the recorded motions (H/V), (iii) by performing 2 dimensional finite difference-based seismic response analyses (Flac-2D), and (iv) ID elastic shear beam solutions. First mode of vibration of the dam in the transverse direction by all four methods were estimated in the range of 0.55 to 0.62 second. Similar close agreement was not observed in higher modal periods estimated by H/V technique as compared to the predictions by C/F, Flac-2D, shear beam analysis techniques. Thus, H/V technique was concluded to be useful for the estimation of the fundamental resonance frequency of a soil structure, but not for its higher harmonics as consistent with available limited literature. In the longitudinal direction, natural period of the dam was estimated as 0.28 and 0. 82 second by H/V and C/F techniques, respectively. Such disagreement was explained by (i) differences in the definitions of the estimated periods, (ii) internal impedance contrast of the dam, (iii) contributions of 3D valley effects. Single seismometer record obtained from crest level was found to be inadequate for reliably assessing the response of a dam in the longitudinal direction, and it is recommended to install multiple seismometers both within dambody and the abutments. Last but not least, the results of these analyses were further compared by available accelograms recorded at three earthfill and rocknll dams from Japan. In general, it was concluded that the seismic response of Kiralkizi Dam is comparable and within the prediction ranges of available analyses methods and is consistent with the expected response of a dam this height.  相似文献   

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In this note, I present a method to estimate the desired distance between medical facilities. The survival rate of patients improves when the facility is larger, however larger facilities result in a longer driving distance to the facility which decreases the survival rate. I identify the desired distance between facilities for which the survival rate is maximized.  相似文献   

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A NOTE ON LAGGED RESPONSE IN THE DECISION TO MIGRATE   总被引:1,自引:0,他引:1  
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ABSTRACT.  An example in Miernyk (1977) presented a rather counterintuitive result, namely, that introducing accurate exogenous information into an RAS matrix estimating procedure could lead to an estimate that was worse than one generated by RAS using no exogenous information at all. This became an oft-cited black mark against RAS. Miller and Blair (1985) included a different (and small) illustration of the same possibility. It was recently pointed out by one of us that the Miller–Blair numerical results are wrong. For that reason, we decided to reexamine all the empirical evidence we could find on the subject. While figures in both Miernyk and Miller–Blair appear to be wrong, more recent published examples seem to have it right. In short, it is possible to identify examples in which additional (correct) information leads to poorer RAS estimates, at least under several fairly common metrics for comparing "closeness" of matrices. However, the overwhelming majority of the evidence is to the contrary. As a general rule, introduction of accurate exogenous information into RAS improves the resulting estimates, and counterexamples should probably not be taken too seriously.  相似文献   

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From the 17th to the 12th Century B.C. the Hittite Kingdom was one of the most notable powers in the Near East. It ranged over a vast geographical area dominating the surrounding cities and smaller states. Throughout this time the Hittites consistently developed their political system thereby ascending to the level of an empire. From sources pertaining to this era, it can be ascertained that already in the early stages, when the borders were not as extended, the Hittite Kingdom adopted the tradition of sending the king's sons and princes to the newly conquered regions and significant cities.  相似文献   

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