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Ali Haydar Kayhan Kasım Armagan Korkmaz Ayhan Irfanoglu 《Soil Dynamics and Earthquake Engineering》2011
In this study, a solution model is proposed to obtain input ground motion datasets compatible with given design spectra based on meta-heuristic harmony search algorithm. The utility of the solution model is demonstrated by generating ground motion datasets matching the Eurocode-8 design spectra for different soil types out of an extensive database of recorded motions. A total of 352 records are selected from the Pacific Earthquake Engineering Center (PEER) Strong Motion Database based on magnitude, distance, and site conditions to form the original ground motion domain. Then, the proposed harmony search based solution algorithm is applied on the pre-selected 352 time-series to obtain the ground motion record sets compatible with design spectra. The results demonstrate that the proposed HS based solution model provides an efficient way to develop input ground motion record sets that are consistent with code-based design spectra. 相似文献
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The relationship between the palynology and geochemistry of the shales associated with the Küre massive sulfide deposits in the Kastamonu Province, northern Turkey, has been studied. SEM seems to be the most effective method to study the palynology of fusinitic particulate organic matter in these thermally-altered sedimentary rocks. Major thermal maturation indicators obtained from the organic and inorganic fractions of the shales and mineral geothermometers of the orebodies suggest that the shales indicate much lower temperatures that the ore and therefore were deposited after the formation of the massive sulfide ores in the area of study. 相似文献
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Arabian Journal of Geosciences - The uniaxial compressive and tensile strength of rocks are crucial parameters in the design stage of geotechnical structures. However, direct determination of these... 相似文献
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A general framework for multi-criteria optimal design is presented which is well suited for performance-based design of structural systems operating in an uncertain dynamic environment. A decision theoretic approach is used which is based on aggregation of preference functions for the multiple, possibly conflicting, design criteria. This allows the designer to trade off these criteria in a controlled manner during the optimization. Reliability-based design criteria are used to maintain user-specified levels of structural safety by properly taking into account the uncertainties in the modelling and seismic loads that a structure may experience during its lifetime. Code-based requirements are also easily incorporated into this optimal design process. The methodology is demonstrated with a simple example involving the design of a three-storey steel-frame building for which the ground motion uncertainty is characterized by a probabilistic response spectrum which is developed from available attenuation formulas and seismic hazard models. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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Erik Swietlicki Jingchuan Zhou David S. Covert Kaarle Hämeri Bernhard Busch Minna Väkeva Ulrike Dusek Olle H. Berg Alfred Wiedensohler Pasi Aalto Jyrki Mäkelä Bengt G. Martinsson Giorgos Papaspiropoulos Besim Mentes Göran Frank Frank Stratmann 《Tellus. Series B, Chemical and physical meteorology》2000,52(2):201-227
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Measuring unconfined compressive strength (UCS) using standard laboratory tests is a difficult, expensive, and time-consuming task, especially with highly fractured, highly porous, weak rock. This study aims to establish predictive models for the UCS of carbonate rocks formed in various facies and exposed in Tasonu Quarry, northeast Turkey. The objective is to effectively select the explanatory variables from among a subset of the dataset containing total porosity, effective porosity, slake durability index, and P-wave velocity in dry samples and in the solid part of samples. This was based on the adjusted determination coefficient and root-mean-square error values of different linear regression analysis combinations using all possible regression methods. A prediction model for UCS was prepared using generalized regression neural networks (GRNNs). GRNNs were preferred over feed-forward back-propagation algorithm-based neural networks because there is no problem of local minimums in GRNNs. In this study, as a result of all possible regression analyses, alternative combinations involving one, two, and three inputs were used. Through comparison of GRNN performance with that of feed-forward back-propagation algorithm-based neural networks, it is demonstrated that GRNN is a good potential candidate for prediction of the unconfined compressive strength of carbonate rocks. From an examination of other applications of UCS prediction models, it is apparent that the GRNN technique has not been used thus far in this field. This study provides a clear and practical summary of the possible impact of alternative neural network types in UCS prediction. 相似文献
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Adsorption of disperse dyes from aqueous solutions onto calcined alunite has been investigated to assess the possibility of using alunite for removing disperse dyes from aqueous solutions. The effects of particle size, adsorbent mass, initial pH and temperature of the dye solution on the adsorption capacities have been evaluated. Acidic pH was favorable for the adsorption of all dyes: Disperse Blue 56 (DB56), Disperse Red 74 (DR74) and Disperse Yellow 119 (DY119). The experimental data were correlated reasonably well by the Langmuir isotherm and the isotherm parameters (KL and aL) have been calculated. The adsorption capacities were found to be 498, 525 and 500 mg of dye per g of calcined alunite for DB56, DR74 and DY119, respectively. The single-stage batch adsorber design of the adsorption of disperse dyes onto alunite has been studied based on the Langmuir isotherm equation. 相似文献
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In spite of the appearance of new measurement methods in geodetic survey, the importance of the bubble level has not decreased.
The increase of accuracy is one of the most important tasks of geodetic research. In this connection, the reliability of the
testing of high-precision bubble levels must also be increased. This purpose is served by an apparatus for testing bubble
vials which fulfills up-to-date demands. The smallest measurable rotation angle is 0.1 second of arc, the smallest measurable
displacement 0.01 mm. The values can be digitized. 相似文献