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Hashim Bassim Mohammed Al Maliki Ali Alraheem Esam Abd Al-Janabi Ahmed Mohammed Sami Halder Bijay Yaseen Zaher Mundher 《Theoretical and Applied Climatology》2022,148(3-4):881-898
Theoretical and Applied Climatology - Iraq is classified as the fifth most vulnerable country in the world to decreased water and food availability, extreme temperatures, and associated health... 相似文献
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Bijay Kumar Sharma 《Earth, Moon, and Planets》2011,108(1):15-37
In this paper I present a new perspective of the birth and evolution of Planetary Systems. This new perspective presents an
all encompassing and self consistent Paradigm of the birth and evolution of the solar systems. In doing so it redefines astronomy
and rewrites astronomical principles. Kepler and Newton defined a stable and non-evolving elliptical orbits. While this perspective
defines a collapsing or expanding spiral orbit of planets except for Brown Dwarfs. Brown Dwarfs are significant fraction of
the central star. Hence they rapidly evolve from non-Keplerian state to the end point which is a Keplerian state where it
is in stable elliptical orbits. On the basis of the Lunar Laser Ranging Data released by NASA on the Silver Jubilee Celebration
of Man’s Landing on Moon on 21st July 1969–1994, theoretical formulation of Earth-Moon tidal interaction was carried out and
Planetary Satellite Dynamics was established. It was found that this mathematical analysis could as well be applied to Star
and Planets system and since every star could potentially contain an extra-solar system, hence we have a large ensemble of
exo-planets to test our new perspective on the birth and evolution of solar systems. Till date 403 exo-planets have been discovered
in 390 extra-solar systems by radial velocity method, by transiting planet method, by gravitational lensing method, by direct
imaging method and by timing method. I have taken 12 single planet systems, four Brown Dwarf—Star systems and two Brown Dwarf
pairs. Following architectural design rules are corroborated through this study of exo-planets. All planets are born at inner
Clarke’s Orbit what we refer to as inner geo-synchronous orbit in case of Earth-Moon System. The inner Clarke’s Orbit is an
orbit of unstable equilibrium. By any perturbative force such as cosmic particles or radiation pressure, the planet gets tipped
long of aG1 or short of aG1. Here aG1 is inner Clarke’s Orbit. If planet is long of aG1 then it is said to be in extra-synchronous orbit. Here Gravitational Sling Shot effect is in play. In gravity assist planet
fly-by maneuver in space flights, gravitational sling shot is routinely used to boost the space craft to its destination.
The exo-planet can either be launched on death spiral as CLOSE HOT JUPITERS or can be launched on an expanding spiral path
as the planets in our Solar System are. In death spiral, exo-planet less than 5 mJ will get pulverized and vaporized in close proximity to the host star. If the mass is between 5 and 7.5 mJ then it will be partially vaporized and partially engulfed by the host star and if it is greater than 7.5 mJ, then it will be completely ingested by the host star. In the process the planet will deposit all its material and angular
momentum in the Host Star. This will leave tell-tale imprints of ingestion: in such cases host Star will have higher 7Li, host star will become a rapidly rotating progenitor and the host star will have excess IR. All these have been confirmed
by observations of Transiting Planets. It was also found that if the exo-planet are significant fraction of the host star
then those exo-planets rapidly migrate from aG1 to aG2 and have very short Time Constant of Evolution as Brown Dwarfs have. But if exo-planets are insignificant fraction of the
host star as our terrestrial planets are then they are stay put in their original orbit of birth. By corollary this implies
that Giant exo-planets reach nearly Unity Evolution Factor in a fraction of the life span of a solar system. This is particularly
true for brown dwarfs orbiting main sequence stars. In this study four star systems hosting Brown Dwarfs, two Brown Dwarf
pairs and 12 extrasolar systems hosting Jupiter sized planets are selected. In Brown Dwarfs evolution factor is invariably
UNITY or near UNITY irrespective of their respective age and Time Constant of Evolution is very short of the order of year
or tens of years. In case of 12 exo-planets system with increasing mass ratio evolution factor increases and time constant
of evolution shortens from Gy to My though there are two exceptions. TW Hydrae is a special case. This Solar System is newly
born system which is only 9 million years old. Hence its exo-planet has just been born and it is very near its birth place
just as predicted by my hypothesis. In fact it is only slightly greater than aG1. This vindicates our basic premise that planets are always born at inner Clarke’s Orbit. This study vindicates the design
rules which had been postulated at 35th COSPAR Scientific Assembly in 2004 at Paris, France, under the title “New Perspective
on the Birth & Evolution of Solar Systems”. 相似文献
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Bijay Kumar Pokhrel Pierre Chevallier Vazken Andréassian Adnan Ahmad Tahir Yves Arnaud Luc Neppel 《水文科学杂志》2013,58(8):1507-1518
AbstractThe glaciers in the Nepalese Himalayas are retreating due to rising temperatures. Lack of data and information on Nepal’s cryosphere has impeded scientific studies and field investigations in the Nepalese Himalayas. Therefore, IRD France and Ev-K2 CNR Italy have conducted the PAPRIKA (CryosPheric responses to Anthropogenic PRessures in the HIndu Kush-Himalaya regions: impacts on water resources and society adaptation in Nepal) project in Nepal with the financial support of the French and Italian scientific agencies. This project aims to address the current and future evolution of the cryosphere in response to overall environmental changes in South Asia, and its consequences for water resources in Nepal. Thus, two hydrological models, the GR4J lumped precipitation–runoff model and the snowmelt runoff model (SRM), were used in the Dudh Koshi basin. The GR4J model has been successfully applied in different parts of Europe. To obtain better results in such a harsh and rugged topography, modifications needed to be made, particularly in the snow module. The runoff pattern is analysed herein both for past years and, in a sensitivity analysis, for possible future climatic conditions (i.e. precipitation and temperature) using the SRM and GR4J modelling approaches. The results reveal a significant contribution of snow- and glacier-melt to runoff, and the SRM model shows better performance in Nepalese catchments than the GR4J model.
Editor D. Koutsoyiannis; Associate editor D. Gerten 相似文献
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The morphometric and drainage basin analysis of the Umshing River is carried out quantitatively using remote sensing and GIS
techniques. The results are presented concerning the hydrological behavior of Umshing river in order to define multi-scale
geomorphometric landform types. The Umshing basin shows a sub-trellis drainage pattern indicating the litho-structural control
on the drainage. Lithological, structural and geomorphological features control the directions of flow of the tributaries.
It is observed and inferred that the Umshing river catchment is under the stage of creep or tilting and hence is vulnerable
to geohazard. 相似文献
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Samaddar Subhajyoti Choi Junho Misra Bijay Anand Tatano Hirokazu 《Natural Hazards》2015,75(2):1531-1554
Natural Hazards - Recent decades have seen an increasing recognition and consensus among researchers and planners in disaster management in the need to foster social learning... 相似文献
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Kamal Lochan Pruseth Debidarsani Sahoo Bijay Kumar Vivek Kumar 《Journal of the Geological Society of India》2017,89(3):240-246
Detrital monazites can be used to reconstruct the tectonothermal history of their provenance. Dating of beach monazites from Alleppey by EPMA U-Th-Pbtotal technique using the centroid method demonstrates that the ages recorded by even a small number of 28 analyses from a single thin section grain mount can potentially reveal a considerable portion of the tectonothermal history of the Trivamdrum block. Three monazite populations were identified that yielded ages 605 ± 9, 575 ± 23 and 548 ± 11 Ma, which have their more or less exact counterparts reported from the Trivandrum Block. One monazite grain yielded random Paleoproterozoic ages ranging from 1756 Ma to 1345 Ma representing similar ages which earlier have been interpreted as due to differential Pb-loss from >2000 Ma monazites during the late Neoproterozoic-Cambrian metamorphism. 相似文献
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The succession of lithofacies of a part of the Barren Measures Formation of the Talchir Gondwana basin has been studied by
statistical techniques. The lithologies have been grouped under five facies states viz coarse-, medium-, and fine-grained
sandstones, shale and coal for statistical analyses. Markov chain analysis indicates the arrangement of Barren Measures lithofacies
in the form of fining upward cycles. A complete cycle consists of conglomerate or coarse-grained sandstone at the base sequentially
succeeded by medium-and fine-grained sandstones, shales and coal at the top. The entropy analysis puts the Barren Measures
cycles into A-4 type cyclicity, which consists of different proportions of lower, upper and side truncated cycles of lithologic
states. Regression analysis indicates a sympathetic relationship between total thickness of strata (net subsidence) and number
of cycles and an antipathic relationship between average thickness and number of sedimentary cycles. The cyclic sedimentation
of the Barren Measures Formation was controlled by autocyclic process which occurred due to the lateral migration of streams
triggered by intrabasinal differential subsidence. In many instances, the clastic sediments from the laterally migrating rivers
interrupted the cyclic sedimentation resulting in thinner cycles in areas where the number of cycles are more. Principal component
and multivariate regression analyses suggest that the net subsidence of the basin is mostly controlled by the thickness of
sandstones, shale beds and coal stringers. 相似文献
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