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With growing urban expanses, one of the pre-requisites for effective governance is Urban Information Systems (UIS) with content down to individual properties (and individuals). The basic input i.e., a map, in UIS should show individual property boundaries showing the plan outline of all structures existing within, at a scale of 1:1000 and larger with sub-metre to centimeters planimetric and geometric accuracy. With very high resolution remote sensing data of the order of 1m available in hand, it is possible to prepare maps with high resolution spatial content. The present exercise demonstrates a method of preparing a geometrically and planimetrically accurate urban cadastral map on very large scale for a small area of about 5 sq km. IKONOS merged data with 1m resolution is used for the purpose. Mapping was done in conjunction with on-site measurements and sketches. Guides are used to maintain shape symmetry and accuracy of buildings and other features. Working out cost of mapping per unit area is another objective in the present exercise. For want of fully or semi-automatic methods of information extraction from very high resolution remote sensing data, it is imperative that mapping should be carried out in conjunction with some on-site measurements wherever necessary.  相似文献   
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This paper deals with groundwater hydrology at a prominent fracture zone landslide slope (Nuta–Yone landslides) in Japan with an objective to explore an efficient method for the application of landslide stability enhancement measures. The correlation analyses between the hydrological parameters and ground surface movement data at this landslide resulted in low correlation values indicating that the geological formation of the area is extremely complex. For the purpose of understanding the groundwater flow behavior in the landslide area, a three-dimensional transient groundwater flow model was prepared for a part of the landslide slope, where the levels of effectiveness of applied landslide stability enhancement measures (in the form of multilayered deep horizontal drains) are different, and was calibrated against the measured water surface elevations at different piezometer locations. The parameter distributions in the calibrated model and the general directions of the groundwater flow in terms of flow vectors and the results of particle tracking at the model site were interpreted to understand the reasons for variations in effectiveness of existing landslide stability enhancement measures and to find potentially better locations for the implementation of future landslide stability enhancement measures. From the modeling results, it was also understood that groundwater flow model can be effectively used in better planning and locating the landslide stability enhancement measures.  相似文献   
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In the present case study, impact of urbanization and industrial development on the shallow groundwater regime of Saharanpur town of Uttar Pradesh in India is examined with the aim of planning groundwater protection for better governance. The hazardous physicochemical and bacteriological parameters and heavy metals detected in the shallow aquifer include harmful pathogens like fecal coliforms, heavy metals like cadmium, chromium, nitrates and sulphates. An assessment of ground water vulnerability using the well known DRASTIC method has confirmed that the shallow groundwater in some central and southern localities of Saharanpur town fall in the medium risk zones. Further, using field data of 32 electrical resistivity soundings, the protective capacity of the unconfined aquifer is assessed in terms of a ‘total longitudinal conductance’ of the semi-pervious to impervious sediments overlying the unconfined aquifer. However, some areas aligned along a northwest-southeast and in the western parts of the town seem to have relatively higher protective capacity against infiltrating waste pollutants. A ground water protection planning map prepared by combining the DRASTIC map and the ‘potentially hazardous pollutants’ map has brought out the need to install eleven new groundwater quality monitoring wells in the town at locations near the line sources and point sources of pollution. This approach can be readily employed by the decision makers in framing sound guidelines for groundwater protection and governance.  相似文献   
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International Journal of Earth Sciences - The continental breakup history at the northwest continental margin of India remained conjectural due to lack of clearly discernable magnetic anomaly...  相似文献   
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