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981.
Mars is the only extraterrestrial body which could host primitive lifeforms and also has the potential to host a human base in the near future. Towards fulfilling these objectives, several remote sensing missions and rover based missions have been sent to Mars. Still, confirmation of existing or extinct life on this planet in any form has not been achieved and possibly human missions at selected sites in the future are the key to addressing this problem. Here, we have used remote sensing data from Mars Reconnaissance Orbiter(MRO; NASA), Mars Global Surveyor(MGS; NASA), Mars Odyssey(NASA) and Mars Express(MEX; ESA) to devise an exploration strategy for one such area known as Hebrus Valles, which is a potential site for human exploration of the surface of Mars. A geological context map of the Hebrus Valles and Hephaestus Fossae region has been prepared and a candidate landing site has been proposed in the Hebrus Valles region. Suitable rover paths have been worked out from the proposed landing site for harnessing the science and resource potential of the region. The proposed landing site is located in the equatorial region at(20?40′N, 126?23′E) and due to its proximity to the Potential Subsurface Access Candidates(PSACs) in the region, such as sinkholes and skylights and also other resources such as crater ejecta, silicate material and fluvial channels, the site is appropriate for exploration of the region. 相似文献
982.
This study analyses the socioeconomic and demographic make‐up of Koreans in Los Angeles metropolis, the largest hub of Koreans in the United States, to better understand the decentralized concentration of Koreans by addressing their within‐ and among‐group variations. By employing the rarely used measures of correspondence and typology analyses, we delineate the boundaries for Korean clusters using Getis and Ord G* local statistic, wherein each cluster's neighborhood and demographic characteristics are compared to gain nuanced insights of within‐group variations, and its evolution during 1970–2010. Cluster level analysis of Koreatown suggests that even though it was classified as a Korean cluster, Korean Americans were unevenly distributed across these clusters, with underrepresentation in white‐dominant neighborhoods, whereas much of their intraurban spaces were shared with Hispanics. All clusters except extended Koreatown exhibited Li's ethnoburb‐style spatial patterns. The Koreatown and suburban clusters were also distinct in terms of their demographic/ethnic, socioeconomic, educational, age/life cycle, and housing characteristics, suggesting socio‐spatial polarization. Our analysis, challenges the commonly perceived notion of Koreans being a homogenous group and Asians being model minorities. We illustrate significant within‐group differences among the Koreangelos. We, thus, propose innovative measures to analyze population groups to flesh out rich narratives of America's fast changing social geographies. 相似文献
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Arabinda Sharma K. N. Tiwari P. B. S. Bhadoria 《Journal of the Indian Society of Remote Sensing》2009,37(1):139-146
Digital elevation models (DEM) are becoming increasingly important as tools in hydrological research and water resources management.
Since error and uncertainty are inherently associated with spatial data, a complete evaluation of a DEM is of utmost importance
before it is put into subsequent analysis. The present paper offers an innovative approach for quality assessment of contour
interpolated DEMs of different resolutions. Five most frequently cited interpolation methods viz., TIN with linear interpolation,
Inverse Distance Weighing, Thin Plate Spline, Ordinary Kriging and TOPOGRID were selected for gridding of contours at five
different resolutions i.e., 30m, 45m, 60m, 75m and 90m. In order to compare the quality of interpolated DEMs, a qualitative
and quantitative evaluation of inter-polated DEMs for their vertical, horizontal and shape accuracy were carried out. It was
found that different interpolation methods produced DEMs with different levels of artifacts. The analyses of vertical accuracy
suggested that the variations were not pronounced in nature. However, the quantitative comparisons for horizontal and shape
accuracy showed that there was a high level of disparity with significant differences among the interpolated DEMs. 相似文献
984.
Plant species diversity along an altitudinal gradient of Bhabha Valley in western Himalaya 总被引：1，自引：1，他引：0
The present study highlights the rich species diversity of higher plants in the Bhabha Valley of western Himalaya in India. The analysis of species diversity revealed that a total of 313 species of higher plants inhabit the valley with a characteristic of moist alpine shrub vegetation. The herbaceous life forms dominate and increase with increasing altitude. The major representations are from the families Asteraceae, Rosaceae, Lamiaceae and Poaceae, suggesting thereby the alpine meadow nature of the study area. The effect of altitude on species diversity displays a hump-shaped curve which may be attributed to increase in habitat diversity at the median ranges and relatively less habitat diversity at higher altitudes. The anthropogenic pressure at lower altitudes results in low plant diversity towards the bottom of the valley with most of the species being exotic in nature. Though the plant diversity is less at higher altitudinal ranges, the uniqueness is relatively high with high species replacement rates. More than 90 % of variability in the species diversity could be explained using appropriate quantitative and statistical analysis along the altitudinal gradient. The valley harbours 18 threatened and 41 endemic species, most of which occur at higher altitudinal gradients due to habitat specificity. 相似文献
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