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Amit Kumar Arvind Chandra Pandey Najmul Hoda A. T. Jeyaseelan 《Journal of the Indian Society of Remote Sensing》2011,39(2):213-224
The present study analyzes the built-up expansion of Ranchi urban agglomeration over a period of about 8 decades from 1927–2005.
Satellite images and topographical maps were used to evaluate land use dynamics during these periods. Built-up growth of 473.7%
during 1927–2005 was primarily at the expense of agricultural land along with reduction of natural water bodies reflects negative
impacts of built-up expansion, which increased many folds in recent decades. The built-up growth is also analyzed with reference
to population growth, land consumption rate and land transformation. The land loss due to increasing built-up growth of Ranchi
were compared with other capital regions and cities along with population increase to provide insight into the possible scenario
of built-up expansion in Ranchi urban area. 相似文献
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Fatemeh Hadavi Marziyeh Notghi Moghaddam Hoda Mousazadeh 《Arabian Journal of Geosciences》2010,3(2):133-139
The aim of this study is to determine calcareous nannofossil species found in Kamar-Kuh area and demonstrate this use for biostratigraphic studies. The Qom Formation is widely distributed in Kamar-Kuh section and has nine members(a–f). In this study, 12 samples were taken and prepared with smear slide. Some of the determined species are listed below, and some of them are photographed by light and scanning microscope. According to obtained nannofossils, 16 species, nine genera, and six families were determined. Obtained nannofossils indicated age of Burdigalian–Serravalian (middle Miocene) for this section. 相似文献
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Masoud Goharrokhi Hoda Pahlavan David A. Lobb Philip N. Owens Shawn P. Clark 《水文研究》2019,33(15):2048-2056
Collecting a representative time‐integrated sample of fluvial fine‐grained suspended sediment (<63 μm) is an important requirement for the understanding of environmental, geomorphological, and hydrological processes operating within watersheds. This study (a) characterized the hydrodynamic behaviour of a commonly used time‐integrated fine sediment sampler (TIFSS) using an acoustic Doppler velocimeter (ADV) in controlled laboratory conditions and (b) measured the mass collection efficiency (MCE) of the sampler by an acoustic Doppler current profiler under field conditions. The laboratory results indicated that the hydrodynamic evaluations associated with the original development of the TIFSS involved an underestimation of the inlet flow velocity of the sampler that results in a significant overestimation of the theoretical MCE. The ADV data illustrated that the ratio of the inlet flow velocity of the sampler to the ambient velocity was 87% and consequently, it can be assumed that a representative sample of the ambient fine suspended particles entered into the sampler. The field results showed that the particle size distribution of the sediment collected by the TIFSS was statistically similar to that for the ambient sediment in the Red River, Manitoba, Canada. The MCE of the TIFSS in the field trials appeared to be as low as 10%. Collecting a representative sample in the field was consistent with the previous findings that the TIFSS is a suitable sampler for the collection of a representative sample of sufficient mass (e.g., >1 g) for the investigation of the properties of fluvial fine‐grained suspended sediment. Hydrodynamic evaluation of the TIFSS under a wider range of hydraulic conditions is suggested to assess the performance of the sampler during high run‐off events. 相似文献
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Investigation of the ecology of introduced species in new habitats can allow determinations of the degree, direction, and rate of evolutionary change. The introduction of Gambusia holbrooki in the southern Caspian Sea presents such a situation. We evaluated the life history traits of mosquitofish in the Tajan River basin. A total of 744 G. holbrooki specimens were collected between January and December 2008. The maximum observed ages are 0+ years for males and 1+ years for females. Both sexes grew allometrically (negative for males: b=2.442 and positive for females: b=3.232). The overall sex ratio is unbalanced and dominated by females. GSI values suggest that this population of G. holbrooki matures between February–July. The highest mean GSI value is 1.80 for males and 15.97 for females in May. Egg diameter ranges from 1.00 to 3.00 mm with a mean value of 2.098 mm. Absolute fecundity varied from 7 to 57 eggs. Both ova diameter and absolute fecundity were positively correlated to fish size (length and weight). Fecundity relative to total weight fluctuated from 34.44 to 582.64 eggs/g, and to total length from 2.33 to 12.95 eggs/cm. Both were negatively correlated with female size. The characteristics of this population are important with respect to life history of the species. 相似文献
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Hoda Soussa A. A. El Feel S. Z. Alfy M. S. M. Yousif 《Arabian Journal of Geosciences》2012,5(1):45-52
In the last decade, attention has been devoted to the southern part of the Egyptian Red Sea coast due to the large touristic and mining activities. Egypt spares no effort to develop it, to build new urban communities, and to create new job opportunities. Many comprehensive planning studies have been conducted. Many luxurious tourist spots, airports, and harbors have been constructed. These areas are subjected to flash floods, which represent a frequent threat to these urbanization activities that may cause losses in livelihood. By analyzing the geomorphologic features of the study area, intense stream networks are detected that, with the available metrological data, require flood management and analysis to mitigate the possible negative effects and to benefit from the estimation of flood water. Rahbaa basin is a sub-catchment of wadi Hodin. Flash floods within this area threaten the Red Sea coastal plain as well as the main coastal roads. It also directly drained out to the sea, which leads to a loss of huge amounts of flood water that is useful for arid regions. Using geographic information system and remote-sensing tools with the application of a comprehensive graphical modeling (watershed modeling system) supports the hydrological modeling of HEC-1. The total amount of runoff is calculated and the hydrograph of the 50-year return period is computed using rainfall historical data. 相似文献
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Jafar Sadeghi Martiros Khurshudyan Margarit Hakobyan Hoda Farahani 《天文和天体物理学研究(英文版)》2015,(2):175-190
We consider a tachyonic scalar field as a model of dark energy with interaction between components in the case of variable G and Λ. We assume a flat Universe with a specific form of scale factor and study cosmological parameters numerically and graphically. Statefinder analysis is also performed. For a particular choice of interaction parameters we succeed in obtaining an analytical expression of densities. We find that our model will be stable at the late stage but there is an instability in the early Universe, so we propose this model as a realistic model of our Universe. 相似文献
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Aly Marwa M. Refay Neveen H. Elattar Hoda Morsy Karim M. Bandala Erick R. Zein Samir A. Mostafa Mohamed K. 《Natural Hazards》2022,111(2):1107-1119
Natural Hazards - This article aims to provide a thorough assessment of water quality and quantity incorporating the estimation of future patterns as a result of climate change from economic,... 相似文献
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Chunyang Liu Hoda Soltani Kanthasamy K. Muraleetharan Amy B. Cerato Gerald A. Miller Sri Sritharan 《Acta Geotechnica》2016,11(6):1431-1444
Presented in this paper are results of two centrifuge tests on single piles installed in unimproved and improved soft clay (a total of 14 piles), with the relative pile–soil stiffness values varying nearly two orders of magnitude, and subjected to cyclic lateral loading and seismic loading. This research was motivated by the need for better understanding of lateral load behavior of piles in soft clays that are improved using cement deep soil mixing (CDSM). Cyclic test results showed that improving the ground around a pile foundation using CDSM is an effective way to improve the lateral load behavior of that foundation. Depending on the extent of ground improvement, elastic lateral stiffness and ultimate resistance of a pile foundation in improved soil increased by 2–8 times and 4–5 times, respectively, from those of a pile in the unimproved soil. While maximum bending moments and shear forces within piles in unimproved soil occurred at larger depths, those in improved soil occurred at much shallower depths and within the improved zone. The seismic tests revealed that, in general, ground improvement around a pile is an effective method to reduce accelerations and dynamic lateral displacements during earthquakes, provided that the ground is improved at least to a size of 13D × 13D × 9D (length × width × depth), where D is the outside diameter of the pile, for the pile–soil systems tested in this study. The smallest ground improvement used in these tests (9D × 9D × 6D), however, proved ineffective in improving the seismic behavior of the piles. The ground improvement around a pile reduces the fundamental period of the pile–soil system, and therefore, the improved system may produce larger pile top accelerations and/or displacements than the unimproved system depending on the frequency content of the earthquake motion. 相似文献
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Changing women's roles, changing environmental knowledges: evidence from Upper Egypt 总被引：2，自引：0，他引：2
The aim of this paper is to investigate the ways in which changing gender roles in a Bedouin community in Upper Egypt, brought about by settlement over the last 20 years on the shores of Lake Nasser, have impacted on the accumulation and development of indigenous environmental knowledges by Bedouin women. The research was carried out among four groups of Ababda Bedouin in the Eastern Desert of Egypt and involved in-depth monthly conversations carried out over a period of 12 months. The main conclusions of the study are that the women of the study area have had to develop new knowledges which, in some cases, are now different from those held by men because of the different economic circumstances in which many find themselves; that these knowledges are fluid, dynamic and ever-changing with their own internal dynamism; and that socially constructed notions of gender are vital in the development process, notions that are sensitive to both men's and women's interests and their interrelationships. 相似文献
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