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Uncontrolled, yet fragmented peripheral urban expansion has emerged as a menace to urban development. To cope with this rapid urban expansion process, identification of the forces responsible for this rapid urban expansion is a pre-requisite, especially when its threats to habitability are taken into consideration. This study tries to evaluate fragmented uncontrolled urban expansion faced by Kolkata using cellular automata-Markov chain. Urban growth patterns, land use/land cover transformations and spatial allocation correspondence with planning strategy is the main theme of this study. Depending upon the driving forces, the study result indicates a bi-directional urban development potential surface, which might be a result of the biased planning initiative along with middle-class residential demand. This simulation result provides evidence for the planning authority to evaluate the effectiveness of spatial allocation and urban expansion trends and provide flexibility to modify the current allocation scenario.  相似文献   
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The TLP configuration in this paper comes from the case study of the ISSC Derived Loads Committee I.2 in 1985. Two models, Model 1 and Model 2, are created aiming at developing a computational tool to handle hydro-dynamic and structural aspects together to help the TLP designer. Another objective is to generate relevant information for a non-linear static local stress analysis of TLP components from a dynamic hydro-structural global analysis. Model 2 is developed for LUSAS, a general purpose, well established, FE software, to validate the in-house program DCATLP. Model 1 and Model 2 are purposely made slightly different in the tether modelling so that the non-linear formulations in DCATLP to treat a TLP as a coupled system with the hull and tethers can be verified with a straightforward linear step-by-step dynamic analysis in LUSAS. The code in DCATLP has advanced features to account for some complex aspects of TLPs, such as compliant characteristics. The results from DCATLP can be directly used in the reliability based structural design of TLP components and subsequent optimisation studies.  相似文献   
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In this paper a discussion of three failure criteria during a tanker collision takes place. The ‘Fracture Criterion’ developed recently [Glykas, A., Samouelides, E., Das, P.K. (1996) Energy absorption capacity of plates under lateral loading. Proceedings of the 6th International Conference of Offshore and Polar Engineers, Los Angeles '96, Vol. IV, pp. 502–509.], deals with the amount of energy required so that arbitrary crack propagation originates from microscopic material flaws of the steel structure, in areas of high strain concentration during large deflections. This fracture criterion is applied in critical areas of a tanker bow structure during head-on collision with a vertical rigid body and its validity is examined in comparison to other two state of the art failure criteria. The penetration of the tanker vessel as well as the time to rest from the initiation of the collision are determined in relation to the failure criteria.  相似文献   
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Marine bacteria, actinomycetes and fungal strains were isolated from continental slope sediment of the Bay of Bengal and studied for fatty acid profile to investigate their involvement in the benthic food-web. Fifteen different saturated and unsaturated fatty acids from bacterial isolates, 14 from actinomycetes and fungal isolates were detected. The total unsaturated fatty acids in bacterial isolates ranged from 11.85 to 37.26%, while the saturated fatty acid ranged between 42.34 and 80.74%. In actinomycetes isolates, total unsaturated fatty acids varied from 27.86 to 38.85% and saturated fatty acids ranged from 35.29 to 51.25%. In fungal isolates unsaturated fatty acids ranged between 44.62 and 65.52% while saturated FA ranged from 20.80 to 46.30%. The higher percentages of unsaturated fatty acids from the microbial isolates are helpful in anticipating the active participation in the benthic food-web of Bay of Bengal.  相似文献   
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In this paper we have tried to present, coherently, a review of the observations of natural VLF radio emissions, termed chorus, that have been made on the ground and aboard satellites, and also their dependence on various geomagnetic phenomena. We have highlighted current theoretical interpretations of the generation and propagation of chorus signals.  相似文献   
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