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101.
102.
Extensive studies have confirmed the good performance of the N2 method, recommended by Eurocode8, when performing pushover
analyses in regular structures. However, this procedure shows lack of accuracy in predicting the torsional motion of plan-asymmetric
buildings. In order to overcome this problem, Peter Fajfar and his team have proposed an extension of the method based on
a combination of a pushover analysis and of an elastic response spectrum analysis. Since definitive answers about this topic
have not yet been reached, this paper intends to proceed the study applying the extended N2 method to real existing RC buildings.
Three real plan-asymmetric buildings with three, five and eight storeys were assessed. The results obtained with the extended
N2 method were compared with the ones evaluated by means of the original N2 and with the nonlinear dynamic analysis through
the use of semi-artificial ground motions. The analyses were performed for different seismic intensities in order to evaluate
the torsional response of the building through different stages of structural inelasticity. The results obtained show that
the extended N2 method generally reproduces in a very good fashion the real torsional behavior of the analyzed buildings.
The conclusions herein outlined, added to the ones already published by the aforementioned authors, seem to confirm that the
extended N2 method can be introduced in the next version of Eurocode8 as a nonlinear static procedure capable of accurately
predicting the torsional response of plan-asymmetric buildings. 相似文献
103.
A study has been conducted to determine the components of 1RS 1A—LISS-II multispectral data directly related to plant and soil characteristics in the minimum number of features. The first picture taken by LISS—II B camera has been used in this study. After studying the information content and the intrinsic dimensionality of the data the coefficients for brightness and greenness transformations were generated. The intrinsic dimensionality of the IRS data is found to be two. 相似文献
104.
Assessment of reliability in water distribution networks using entropy based measures 总被引：1，自引：0，他引：1
Entropy based expressions for measurement of reliability and redundancy have recently been reported. These measures approach assessment of the reliability of the distribution network from the intrinsic redundancy of the network layout. The paper extends earlier work on entropy functions by including a more explicit statement of the alternate paths available in the network and by recognizing that under certain circumstances, e.g., failure of some part of the network work, an outflow link from a node under normal working condition may become an inflow link to the same node. The measures are assessed by comparison with parameters measuring Nodal Pair Reliability and percentage of flow supplied at adequate pressure for a range of networks and link failure conditions in this networks. The entropy measures are shown to reflect changes in the network reliability, as measured by these two comparative parameters, very well. 相似文献
105.
C. M. Bhatt P. K. Litoria P. K. Sharma 《Journal of the Indian Society of Remote Sensing》2008,36(4):361-373
Bist Doab interfluvial tract in the north-western part of Punjab, India, has been investigated for geomorphic signatures of
active tectonics using remotely sensed data and geographical information system (GIS). The anomalous river flow, abrupt changes
in flow direction, angular drainage, compressed meanders, asymmetry of river bends, high channel sinuosity, abandoned channels,
water-logged and marshy areas observed along the courses of Beas and Sutlej rivers and their tributaries indicate tectonically
active nature of the terrain. The strong control exercised by the NE-SW and NW-SE trending lineaments on the drainage network
is well evident in the form of long straightened slope deviatory courses, definite changes in channel pattern and sharp knee
bend turns taken by the seasonal rivulets. The asymmetric and elongated nature of watersheds and straight to curvilinear mountain
fronts quantified through morphotectonic analysis are characteristic of tectonically active settings and further corroborate
the evidence of active tectonics. 相似文献
106.
Shashi B. Shukla Vikas M. Chowksey Siddharth P. Prizomwala Vishal M. Ukey Nilesh P. Bhatt Deepak M. Maurya 《Acta Geophysica》2013,61(5):1196-1210
The coastline constitutes a very sensitive geomorphic domain which is constantly subjected to dynamic coastal processes and stores vital information regarding past sea level fluctuations. A ground-penetrating radar (GPR) survey was carried out along the northern coast of the Gulf of Kachchh which is one of the largest macrotidal inlets of the Arabian Sea, Western India. Our studies have delineated several radar surfaces and radar facies which reflect the internal architecture and sediment body geometry, which can be related to the processes acting along this coastline. Various radar facies, namely, beach ridge (Br), washover (Wo), coastal dune (Cd), swale (Sw), berm plain (Bp), and sandsheet facies (Ss) have been identified. The GPR studies successfully documented the subsurface presence of ancient beach ridge system towards the sea, and the coastal dunes towards the land side. The results are suggestive of signatures of changes in sea level and the coastline being prone to high energy events in the recent past. The GPR has been found to be an important non-invasive geophysical tool in the study of past coastal dynamics. 相似文献
107.
108.
Jayesh S. Bhatt † Ian J. Ford 《Monthly notices of the Royal Astronomical Society》2007,382(1):291-298
The possibility of magnesium oxide being the first species to nucleate in the cooling outflows around M stars has been investigated. By treating the formation of the seed nuclei as a homogeneous nucleation problem and using molecular dynamics data obtained with the 'compressible ion potential' for MgO, free energy calculations are performed to obtain an estimate of the population densities of MgO clusters of various sizes. It is found that a free energy barrier of at least hundreds of k B T would need to be climbed in order for MgO to nucleate in significant amount in typical circumstellar shells, hence ruling out MgO as a realistic candidate for the primary nucleating dust species. This is in agreement with a similar conclusion reached in earlier studies, although the present calculations are based on a much more robust potential model for MgO. 相似文献
109.
110.