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91.
Maged M. A. Hussein 《Arabian Journal of Geosciences》2018,11(24):768
The best evaporation estimate method for Alexandria Eastern Harbor has been derived following the evaluation of performance of five evaporation estimate methods, namely, (1) Bowen ratio energy balance (BREB), (2) De Bruin–Keijman (DK), (3) Priestley–Taylor (PT), (4) Brutsaert–Stricker (BS), and (5) Penman (PM), based on two consecutive summer seasons of 2010 and 2011 data. Different statistical measurements of goodness of fit, namely, coefficient of determination (R2), root mean square error (RMSE), relative bias (RB), and index of agreement (D) have been chosen for the evaluation of the performance. When the Bowen ratio is known a priori, the DK and PT methods have been found the best evaporation estimate methods. The responses of the three methods BREB, DK, and PT were found comparable to each other, while the PM method response differed to match with the responses of the other three methods. The Bowen ration (β) of 0.05 and Priestley–Taylor (PT) coefficient (α) of 1.23 derived from the analysis can be extended for evaporation estimates in Alexandria Eastern Harbor, Egypt. 相似文献
92.
Alsharifa Hind Mohammad Hahn Chul Jung Taleb Odeh Chandrashekhar Bhuiyan Hussam Hussein 《Arabian Journal of Geosciences》2018,11(5):103
This article assesses drought status in the Yarmouk Basin (YB), in northern Jordan, using the Standardized Precipitation Index (SPI), the Standardized Water-Level Index (SWI), and the Percent Departure from Normal rainfall (PDNimd) during the years 1993–2014. The results showed that the YB suffers from frequent and irregular periods of drought as variations in drought intensity and frequency have been observed. The SPI results revealed that the highest drought magnitude of ??2.34 appeared at Nuaimeh rainfall station in 1991. This station has also experienced severe drought particularly in years 1995, 1999, 2005, and 2012 with SPI values ranging from ??1.51 to ??1.59. Some other rainfall stations such as Baqura, Ibbin, Khanasiri, Kharja, Mafraq police, Ramtha, Turra, and Umm Qais have also suffered several periods of drought mostly in 1993. The SWI results show the highest extreme drought events in 2001 in Souf well while other extreme drought periods were observed at Wadi Elyabis well in 1994 and at Mafraq well in 1995. As compared to SPI maps, our SWI maps reflect severe and extreme drought events in most years, negatively impacting the groundwater levels in the study area. 相似文献
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Mohammed Musa Amro Mohammed Said Benzagouta Wimpy Karnanda 《Arabian Journal of Geosciences》2013,6(3):873-880
The main objectives of this paper are to study crude oil migration as a toxic fluid, its rate of penetration, and its consequences for eventual treatment. To achieve these objectives, an experimental model was designed comprising two separated columns, filled with soil and other rock types to simulate a real case scenario. Crude oil penetration depth versus time was recorded by taking soil samples whereas water samples were collected from the wet system to analyze the penetrating liquid. The results show that penetration depth was greater in the wet system during the early stages rather than in the dry system. However, with time, penetration becomes more developed in both systems. Overall penetration in the final stage was found to be significantly higher in the dry system. In addition, it was observed that during crude oil migration in dry system, chromatographic separation of crude oil components has occurred obviously. The obtained results reveal that immediate treatment must be performed in both systems but particularly in the wet system, due to its higher initial penetration rate. 相似文献
95.
Husam Musa Baalousha 《Environmental Earth Sciences》2012,66(1):285-294
Modelling groundwater and surface water is important for integrated water resources management, especially when interaction
between the river and the aquifer is high. A transient groundwater and surface water flow model was built for Ruataniwha basin,
New Zealand. The model covers a long-time period; starting in 1990, when water resources development in the area started,
to present date. For a better resolution, the simulation period was divided into 59 stress periods, and each stress period
was divided to 10 time steps. The model uses data obtained from surface water, and groundwater collected over the last 20 years.
Rivers and streams were divided into 28 segments and flow and streambed data at the beginning and end of each segment was
used. Parameter estimation and optimisation ‘PEST’ was used for automatic calibration of hydraulic conductivity, groundwater
recharge and storativity; whereas riverbed conductance was manually calibrated. Model results show that the rivers gain from
the aquifer considerably more than the river losses. The cumulative groundwater abstraction over the last 20 years is approximately
210 million m3. This amount is very low compared to other water budget components; however, the effect of groundwater abstraction on storage
is significant. Based on the results of this study, it was found that the loss of storage over the last 20 years is more than
66 million m3. Results also reveal that the effect of groundwater abstraction on rivers and springs flow is significant. The rivers gain
from the groundwater system, and the springs flow have been decreasing. 相似文献
96.
Khalid S. Aldamegh Hesham Hussein Moussa S. Nasser Al-Arifi Sayed S. R. Moustafa Moustafa Hemeda Moustafa 《Arabian Journal of Geosciences》2012,5(4):599-606
Focal mechanism solution of the 27th August 2009 earthquake (mb?=?4.0) that occurred in the Badr area, northwest of Saudi Arabia, approximately 50?km from the Red Sea has been determined from the P-wave first motion polarities. Results show normal faulting mechanism with a negligible component of strike-slip motion with NE T-axis direction. This type of mechanism is common with other earthquakes of the northwestern Saudi Arabia and is considered to present the tectonic movement of the region. The dominantly extensional tectonic regime in this province demonstrates the influence of NE extension in the Red Sea. The strikes of the solution are consistent with those of the main faults near the epicenter. Hypocentral location of this earthquake was carried out using the data from the King Abdulaziz City of Science and Technology Seismic Network, Saudi Arabia, and the Egyptian National Seismological Network, Egypt. The horizontal and vertical confidence estimates are 0.5?km for both. The local magnitude, M L, following the Richter??s original definition was also derived from ten digital three-component broadband seismograms. The average local magnitude determined in this study is 3.8?±?0.17. The estimated seismic moment of this event is $ {3}.{\hbox{7e}} + {14}\,{\hbox{Nm}}\left( {{M_{\rm{W}}} = {3}.{66}\pm 0.0{7}} \right) $ . 相似文献
97.
Snehamoy Chatterjee Roussos Dimitrakopoulos Hussein Mustapha 《Mathematical Geosciences》2012,44(3):343-374
A pattern-based simulation technique using wavelet analysis is proposed for the simulation (wavesim) of categorical and continuous variables. Patterns are extracted by scanning a training image with a template and then storing
them in a pattern database. The dimension reduction of patterns in the pattern database is performed by wavelet decomposition
at certain scale and the approximate sub-band is used for pattern database classification. The pattern database classification
is performed by the k-means clustering algorithm and classes are represented by a class prototype. For the simulation of categorical variables,
the conditional cumulative density function (ccdf) for each class is generated based on the frequency of the individual categories at the central node of the template. During
the simulation process, the similarity of the conditioning data event with the class prototypes is measured using the L
2-norm. When simulating categorical variables, the ccdf of the best matched class is used to draw a pattern from a class. When continuous variables are simulated, a random pattern
is drawn from the best matched class. Several examples of conditional and unconditional simulation with two- and three- dimensional
data sets show that the spatial continuity of geometric features and shapes is well reproduced. A comparative study with the
filtersim algorithm shows that the wavesim performs better than filtersim in all examples. A full-field case study at the Olympic Dam base metals deposit, South Australia, simulates the lithological
rock-type units as categorical variables. Results show that the proportions of various rock-type units in the hard data are
well reproduced when similar to those in the training image; when rock-type proportions between the training image and hard
data differ, the results show a compromise between the two. 相似文献
98.
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100.
Ibrahim A A Fadoul A M Musa T A Yao AiguoEngineering Faculty China University of Geosciences Wuhan 《中国地质大学学报(英文版)》2001,12(3)
INTRODUCTIONDrillingoptimizationisthelogicalprocessofanalyzingef fectsandinteractionsofdrillingvariablesthroughmathematicalmodelingtoachievemaximumdrillingefficiency .Thereductionofcoststhroughtheuseofoptimumtechniquesdoesnotstemfromfasterpenetrationr… 相似文献