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This article deals with the finite element analysis of dam with and without fluid-structure, soil-structure and soil-structure-fluid interaction. A two-dimensional direct coupling methodology is proposed to obtain the response of dam-reservoir-foundation system considering fluid-structure and soil-structure interaction simultaneously. The displacement based finite element technique is used to formulate the dam and foundation. The reservoir is modeled by pressure based finite element to reduce the degree of freedoms and there by the computational cost. The responses of dam, reservoir, and foundation with and without fluid-structure, soil-structure and soil-structure-fluid interaction are compared to study the influence of reservoir and soil foundation on the behavior of these respective sub systems. The fundamental frequency of individual sub system decreases with the consideration of coupling effect among these sub systems. On the comparison of the responses of dam, it is observed that the displacement and principal stresses are increased if the effect of reservoir and foundation are considered and the worst responses were observed when both the fluid-structure and soil-structure interaction effects are considered simultaneously. The magnitude and distribution of stresses within the foundation change with the consideration of soil-structure-fluid interaction. Similar to wstresses in the foundation, the hydrodynamic pressure within the reservoir also gets magnified due to interaction effects. The velocity distribution within the reservoir becomes distorted when the fluid-structure and soil-structure-fluid interaction are considered. 相似文献
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Plagioclase feldspar is the major luminescent mineral in meteorites. Thermoluminescence (TL) characteristics, peak temperature (Tm), full width at half maximum (FWHM), ratio of high (HT) to low temperature (LT) peak, and TL sensitivity (TL/dose/mass) to an extent reflect degree of crystallinity of the mineral. The present study explores and establishes a correlation between quantum mechanical anomalous (athermal) fading and structural state by examining TL of individual chondrules. Chondrules were separated using freeze-thaw technique from a single fragment of Dhajala meteorite. The results show large variation in Tm (155?230°C), FWHM (80?210°C) and HT/LT (0.07–0.47) and seem to be positively correlated. TL sensitivity (ranging from 14 to 554 counts/s/Gy/mg) decreases with increasing Tm and FWHM. Large variations in TL parameters (Tm, FWHM, HT/LT, and Sensitivty) suggest that individual chondrules had different degree of crystallization. Thermal annealing experiments suggest that comparatively ordered form of feldspar can be converted to a disordered form by annealing the sample at high temperatures (1000°C) for long time (10 hr) in vacuum (1 mbar pressure) condition and rapidly cooling it. Measured anomalous fading suggest that fading rate increases as the crystal form changes from an ordered state to a disordered state. However, the fading rate becomes nearly negligible for the most disordered feldspars. 相似文献
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Amiya Kumar Bagchi 《Development and change》2008,39(2):197-218
This article critiques the liberal and state‐centred view of morality and governance as applied to immigrants. It argues that the alternative perspective provided by some moral philosophers and political theorists can be combined with analysis of the current global economic and political order to outline a framework for protecting the welfare and human rights of the immigrants. It also argues that this framework brings out the commonality of interests of workers in host countries and immigrants in re‐empowering the state to provide for the comprehensive social security that the neoliberal state has trashed. 相似文献
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Krishan Kumar 《Nations & Nationalism》2015,21(4):589-608
Nationalism and revolution have generally been held to go together. Many nation‐states have had their origins in revolution, from the Americans in the 18th century to a host of Third World nation‐states in the 20th century. Generally, both modern revolutions and modern nationalism have the same origins, in 18th century Enlightenment thought. But this paper argues that, despite this common origin, the principles of revolution and nationalism are divergent, and can set one against the other. Revolutions emphasise freedom and equality; nationalism emphasises integration and unification. These principles can clash, though not inevitably and not always. The paper examines the 1789 French Revolution, the 1848 revolutions and the 1917 Russian revolution. It shows that in the first two cases, revolutionary aspirations came up against and were eventually displaced by nationalist aims. In the case of 1917, revolution paradoxically, and unintentionally, institutionalised nationalism. These examples show that, though linked at some high level of modern thought, revolution and nationalism express different and at times divergent strands of modernity. 相似文献
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Hemant Kumar Vinayak Ashok Kumar Pankaj Agarwal Shashi Kant Thakkar 《Journal of Earthquake Engineering》2013,17(5):771-787
This article puts forth the work on a neural network-based approach to determine the degree of damaged floors of the building considering changes in the transfer function. The transfer function is considered for that part of forced vibration in which system vibrates linearly after the structure has been damaged considering the building is instrumented during the earthquake. The results showed that accuracy of degree of damage detected increased with the increase in the number of combination of damages. The instrumentation of the first floor is expected to give best results for damage detection based on the transfer function-based approach. 相似文献
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J. P. Singh Pankaj Agarwal Ashok Kumar S. K. Thakkar 《Journal of Earthquake Engineering》2014,18(3):444-457
Modal parameters of an instrumented multi-storied reinforced concrete building (G +9) have been studied using strong motion records of Bhuj Earthquake, 2001. The Ambient Vibration Testing (AVT) is also conducted to measure the modal parameters of the same building under ambient environmental forces. Frequency Domain Decomposition (FDD) or Peak Picking (PP) in frequency domain and Stochastic Subspace Identification (SSI) technique in time domain is used for extracting the modal parameters. The observed natural frequencies during strong motion are smaller than the ambient vibration testing. The difference in the frequencies may be caused by interaction between structure and soil due to high level of strain during strong motion earthquake. The modal pattern of first five modes obtained from strong motion records and ambient vibration records are identical. 相似文献
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Prabha Kalia Prabhas Kumar Pande Trilochan Singh 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):207-227
Foraminiferal assemblage from Permian rocks of Eastern Himalaya, India are recorded for the first time. Twenty-two genera and twenty-eight species are documented from the Garu Formation, Eastern Himalaya. The foraminiferal assemblage supports previous age determinations based on megafauna. The distinctive foraminiferal assemblage from India supports the recognition of Australian and Afghanistan-Indian provinces in the Early Permian Austral realm. An appreciable number of common species in these provinces is indicative of close geographic links. 相似文献
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An ethno-archaeological study of the people of Thongjao village considered to be one of the ancient pottery makers in Manipur provided a detailed account of the techniques and procedures of pottery making. The present study attempts to bridge the gap between the present ethnographic account and past archaeological account in respect of the ceramics of Manipur by drawing similarities between the Thongjao village and prehistoric ceramics of Manipur on the one hand and by making analogical interpretations of the latter on the basis of parallelism that exists between the two on the other. This study also highlighted the use of raw materials and their techniques used in making pottery and their prehistoric similarities in respect of their composition. The paper studies the different types of pottery found in this village and also reveals the socio-cultural association of the people, changes and continuity. 相似文献