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611.
Hassan S. Naji Mohammad H. Hakimi Mohammed Khalil Farooq A. Sharief 《Arabian Journal of Geosciences》2010,3(3):221-248
The Masila area is located in the Hadhramaut region in east central Yemen. Oil was first discovered in the area in late 1990 with commerciality being declared in late 1991. Oil production began in July 1993. By the end of December 1999, the daily production rate was set at 210,000 stock tank barrels/day (STB/D) of very low gas–oil ratio (GOR) oil under partial to full water drive. About 90% of the reserves are found in the Lower Qishn Clastics Member of the Qishn Formation. This paper focuses on the detailed 3D geological modeling of the Lower Cretaceous Sequence conducted through an integrated study. There are three critical areas in the process of modeling reservoirs that involve geological and geophysical modeling, reservoir characterization, and reservoir flow modeling. This paper presents methodologies found useful during the modeling of these reservoirs including field case histories for the Lower Cretaceous reservoir in the Masila oilfield. 相似文献
612.
Abdel-Fattah Attia Hamed A. Ismail Hassan M. Basurah 《Astrophysics and Space Science》2013,344(1):5-11
The paper presents a Neuro-Fuzzy model to predict the features of the forthcoming sunspot cycles 24 and 25. The sunspot time series were analyzed with the proposed model. It is optimized based on Backpropagation scheme and applied to the yearly smoothed sunspot numbers. The appropriate number of network inputs for the sunspots data series is obtained based on sequential forward search for the Neuro-Fuzzy model. According to the model prediction the maximum amplitudes of the cycles 24 and 25 will occur in the year 2013 and year 2022 with peaks of 101±8 and 90.7±8, respectively. The correlation and error analysis are discussed to ensure the performance of the proposed Neuro-Fuzzy approach as a predictor for sunspot time series. The correlation coefficient between Neuro-Fuzzy model forecasted sunspot number values with the actual ones is 0.96. 相似文献
613.
Water Resources - Hydrological runoff prediction in a reliable and precise manner contributes significantly to the optimal management of hydropower resources. Considering the importance of runoff... 相似文献
614.
Masood Ahsan Siddiqui Syed Mohammad Rashid Lubna Siddiqui Shahzad Ali Ansari 《Journal of the Indian Society of Remote Sensing》2012,40(1):109-119
The paper tries to estimate the rate of waste generation per head/per day, to identify suitable sites for waste disposal,
to find out optimal route for collection vehicles and to analyze the financial aspects of solid waste management in Moradabad
City, India.The study is based on sample of 2,500 households and secondary data. The City generates about 318 tones of solid
waste with an average per capita rate of 460 gram per day. Collection and disposal efficiency is nearly 64%. Sensitivity analysis
of the present disposal site as per the norms of Central Pollution Control Board indicates that it is moderately suitable.
Subsequently two new disposal sites were identified. Redefined routes and related issues were evaluated in financial terms.
It is estimated that by adopting the proposed plan, the expenditure on waste management will increase by about 52%, but at
the same time about 90% of city area and 95% of city population will be served. 相似文献
615.
Investigation of radio astronomical windows between 1 MHz and 2060 MHz in Universiti Malaya,Malaysia
Zamri Zainal Abidin Zainol Abidin Ibrahim Syed Bahari Ramadzan Syed Adnan Norwati Khairul Anuar 《New Astronomy》2009,14(6):579-583
An indoor and an outdoor radio frequency survey was conducted in Universiti Malaya, Malaysia, as a test site, for the purpose of developing radio astronomy research in Malaysia. This is the first radio astronomical survey of any such done in Malaysia. Observation and analysis were done in the radio frequency spectrum between 1 MHz and 2060 MHz. In this paper, the experimental setup and procedure of surveying are outlined and the measured data are interpreted. The eight radio astronomical windows were investigated from a 24 h observation, with the emphasis on two of the most important radio astronomical windows which are protected by the Malaysian Communications and Multimedia Commission (MCMC). Some intermittent observations were also done for referencing purposes. The radio frequency interferences (RFIs) are found to be relatively low. The overall relative Interference-to-Noise ratio (INR) at this test site ranges between 5.72% and 11.74%. The average strength of RFI in the eight focused radio astronomical windows at this site ranges between ?100 dBm and ?90 dBm (equivalently between 9.23 × 104 Jy and 93.29 × 104 Jy at resolution bandwidth of 125 kHz). 相似文献
616.
617.
The young open star cluster M25 (IC 4725) is located in the direction of the galactic center, near much irregular absorption
features on Sagittarius arm. This system is found to be at a distance of 600 pc, with a median age of 9.45 × 107 years and a distance from the galactic plane of –52.82 pc The mass data available in the literature has been gathered and
many statistical methods have been applied for this cluster. Depending only on these methods, the stellar density, the distribution
of dark matter, the luminosity and the mass functions have been estimated. The center of the cluster has been defined, it
is shifted by 45 arc sec in the northeast direction. The radius of the cluster is found to be 4 pc. More than 220 stars with
mean reddening of 0.50 mag and absorption of 1.62mag are found inside this aria. The total mass of the cluster has been estimated
with the mass of the interstellar matter (gas and dust). It is found to be 1937 M
⊙, whereas about 24% of the material mass of the cluster has remained as interstellar matter after the processes of formation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
618.
Wahab Uddin Ramesh Chandra Syed Salman Ali 《Journal of Astrophysics and Astronomy》2006,27(2-3):267-276
We observed 4B/X17.2 flare in Hα from super-active region NOAA 10486 at ARIES, Nainital. This is one of the largest flares
of current solar cycle 23, which occurred near the Sun’s center and produced extremely energetic emission almost at all wavelengths
from γ-ray to radio-waves. The flare is associated with a bright/fast full-halo earth directed CME, strong type II, type III
and type IV radio bursts, an intense proton event and GLE. This flare is well observed by SOHO, RHESSI and TRACE. Our Hα observations
show the stretching/de-twisting and eruption of helically twisted S shaped (sigmoid) filament in the south-west direction
of the active region with bright shock front followed by rapid increase in intensity and area of the gigantic flare. The flare
shows almost similar evolution in Hα, EUV and UV. We measure the speed of Hα ribbon separation and the mean value is ∼ 70
km s-1. This is used together with photospheric magnetic field to infer a magnetic reconnection rate at three HXR sources at the
flare maximum. In this paper, we also discuss the energetics of active region filament, flare and associated CME. 相似文献
619.
The Fokker-Planck equation for small stochastic changes to particles in Kepler orbits has to be formulated in terms of the integrals of motion. We generalize the modelling of proton and electron collisional perturbations to gas particles on trajectories through the solar system in order to include both spatial and velocity diffusion. The general solution is obtained in terms of a 4-dimensional normal distribution. Treatment of the singularity in the Fokker-Planck operator reduces the dimensionality by one. In addition to extending earlier results for anisotropic collisional heating in the thermal approximation, the present formulation gives the changes in density due to the mean repulsive force and to perturbations of trajectories (spatial diffusion). The net diffusion is almost everywhere towards the sun and the density increase is significant in the downstream hydrogen wake, particularly where destructive depletion is strong and gravitational focussing weak. 相似文献
620.