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Ehab ElGindy Alia Abdelmoty 《International journal of geographical information science》2014,28(7):1439-1458
Geo-folksonomies link social web users to geographic places through the tags users choose to label the places with. These tags can be a valuable source of information about the user’s perception of place and can reflect their experiences and activities in the places they label. By analysing the associations between users, places and tags, an understanding of a place and its relationships with other places can be drawn. This place characterisation is unique, dynamic and reflects the perception of a particular user community that generated the geo-folksonomy. In this work, an approach is proposed to analysing geo-folksonomies that builds on and extends existing statistical methods by considering specific concepts of relevance to geographic place resources, namely, place types and place-related activities, and by building a place ontology to encode those concepts and relationships. The folksonomy analysis and evaluation are demonstrated using a realistic geo-folksonomy data set. The resulting ontology is used to build user profiles from the folksonomy. The derived profiles reflect the association between users and the specific places they tag as well as other places with relevant associated place type and activities. The methods proposed here provide the potential for many interesting and useful applications, including the harvesting of useful insight on geographic space and employing the derived user profiles to enhance the search experience and to identify similarities between users based on their association to geographic places. 相似文献
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Roland Vanderspek Alia Atlas Tye M. Brady Geoffrey B. Crew John P. Doty Steven E. Kissel George R. Ricker Peter C. Tappan Francois Martel M. Tim Jones 《Astrophysics and Space Science》1995,231(1-2):479-482
The High Energy Transient Experiment (HETE), scheduled for launch this year, is a small satellite dedicated to multiwavelength observations of -ray and X-ray bursts. The HETE spacecraft will be equipped with gamma-ray detectors, X-ray detectors with a coded mask, and ultraviolet-sensitive CCD cameras. The UV cameras on HETE are wide-field imagers which will a) provide UV images of the regions in which -ray or X-ray bursts are detected, before, duringand after the burst, b) detect UV transients, whether associated with a high-energy transient or not, c) monitor the brightnesses of field stars for variability over a wide range of timescales, and d) serve as star trackers for HETE. In this poster, we describe the HETE UV instrumentation, control software, and data products. 相似文献
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Ziaur Rehman Ansari L. A. K. Rao Alia Yusuf 《Journal of the Geological Society of India》2012,79(5):505-514
Remote Sensing and GIS techniques have been proved to be efficient tools in the delineation, updating and morphometric analysis of drainage basin. The present study incorporates a morphometric analysis of three sub-basins of Fatehabad area of Agra district using remote sensing and GIS techniques. The morphometric parameters of the sub-basins are classified under linear, areal and relief aspects. The drainage pattern exhibited by the main river Yamuna and its tributaries shows a dendritic pattern indicating homogenously underlain material while the mean bifurcation ratio values suggest that the geological structures are not disturbing the drainage pattern. The form factor value of sub-basins suggests that the main basin is more or less elongated. Circularity ratio values of the three sub-basins fall within range of elongated basin and low discharge. The area has low density indicating that the region has high permeable sub-soil material and dense vegetation. The values of drainage texture, drainage density and infiltration number indicate that sub-basin-III has the highest infiltration rate and low runoff, hence contributing most to the underground water resources. This study also indicates porous and permeable sub-soil condition in sub-basin-III. The values of sub-basin-I indicate low permeable subsoil material owning to high infiltration number value, hence low infiltration and high runoff. 相似文献
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Muhammad Ibrahim Muhammad Yamin Ghulam Sarwar Alia Anayat Fareeha Habib Sami Ullah 《Applied Geochemistry》2011
Tillage systems affect soil properties, crop growth and nutrient uptake under various agro-ecological conditions. The uptake of water and nutrients are largely dependent on the root systems of wheat (Triticum aestivum L.) and rice (Oryza sativa L.). The application of manure has direct influence on the nutrient uptake by the crop plants. A 2 year field experiment was conducted to evaluate the impact of tillage and farm manure on root growth by measuring the root length density on a sandy clay loam (Typic calciargid soil). Three tillage systems were used; (i) minimum tillage (MT), (ii) deep tillage (DT) and (iii) conventional tillage (CT). Three farm manure levels were used; (i) FM0 (only chemical fertilizers), (ii) FM15 (farm manure at 15 Mg ha?1) and (iii) FM30 (farm manure at 30 Mg ha?1). The incorporation of farm manure into soil markedly improved the root length density (RLD) of both wheat and rice crops. For wheat, the application of FM30 increased RLD by 16% and 9% in cases of deep tillage and minimum tillage, respectively. For rice, the increase in RLD at the same farm manure rate (FM30) was 13% and 17%, during first and second year, respectively. Averaged across tillage, the trend of RLD for both wheat and rice was DT > CT > MT. The incorporation of FM has increased the uptake of N, P and K significantly (P < 0.05), thereby increasing the agronomic parameters. The manure may be used to ameliorate the deleterious effects of tillage for sustainable crop yield. 相似文献
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