A Conceptual Rainfall-Runoff Model Using the Auto Calibrated NAM Models in the Sarisoo River

This paper describes the application of a conceptual rainfall runoff model to investigate the peak and monthly flows at the Sarisoo River Basin on the North West of Iran. The model was calibrated using measured stream flow data and then validated for three years. Calculations of level and time of peak flows are vital for designing structures downstream in the catchment areas. The simulated peak flows were occurring in the months of February in 2003, 2006 and 2007 with approximate values of 6.32, 9.35 and 6.13 m3s-1 respectively. After calibrating 9 NAM parameters using record data of daily rainfall, monthly evaporation and daily discharge in the period of 1th October 2003 to 31th March 2006 and validating the model daily discharges were calculated for 12 years. The outputs of the calibrated model are able to be used in the assessment of water resources management models like Mike Basin, WEAP… because they normally work based on monthly flows with a large time horizon. The results show that monthly averages of mean, maximum and minimum flows are about 10%, 2% and 33% less than daily computed Nash–Sutcliffe coefficients, all calculated over a period of 12 years. The optimum values of the 9 NAM parameters obtained during the calibration procedure are presented. The reliability of MIKE11 NAM was evaluated based on the Nash–Sutcliffe coefficient (R2), Root Mean Square Error (RMSE), peak flow (RMSE) and low flow (RMSE). The R2 obtained during this study is 0.74

Flow of forces and couples to the cylindrical solids through system asymmetry thin-walled elements of varying stiffness

Задача про передачу силового і моментного навантаження до криволінійного отвору нескінченної ізотропної пластинки через систему несиметричних відносно серединної площини тонкостінних елементів змінної жорсткості зведена до системи чотирьох сингулярних інтегрально– диференціальних рівнянь з ядрами Гільберта. Методом колокації досліджується вплив на напружений стан пластинки несиметричності підсилень, способу їх розміщення на контурі отвору.The problem of flow of forces and couples to the curvilinear hole in a infinite isotropic plate through system of asymmetrical by a middle plane the thin-walled elements of varying stiffness reduce to the system of four singular integral-differential equations with cores of Hilbert. The effect of asymmetry strengthens and location mode by method of collocation does investigate

Time-dependent Hybrid Plasma Simulations of Lunar Electromagnetic Induction in the Solar Wind

No abstract availabl

Modeling the Lunar plasma wake

This thesis discusses the solar wind interaction with the Moon and the formation of the lunar plasma wake from a kinetic perspective. The Moon is essentially a non-conducting body which has a tenuous atmosphere and no global magnetic fields. The solar wind plasma impacts directly the lunar day-side and is absorbed by the lunar surface. This creates a plasma void and forms a wake at the night side of the Moon.We study the properties and structure of the lunar wake for typical solar wind conditions using a three-dimensional hybrid plasma solver. Also, we study the solar wind proton velocity space distribution functions at close distances to the Moon in the lunar wake and investigate the effects of lunar surface plasma absorption and non-isothermal solar wind velocity space distribution functions on the solar wind protons there.Finally, we compare the simulation results with the observations and show that a hybrid model of plasma can explain the kinetic aspects of the lunar wake and we investigate the effects of the lunar surface plasma absorption and non-isothermal solar wind velocity distribution on the solar wind proton properties there.Godkänd; 2011; 20111114 (shafat); LICENTIATSEMINARIUM Ämnesområde: Rymdteknik/Space Engineering Examinator: Docent Mats Holmström, IRF Kiruna Diskutant: Senior Scientist Bengt Eliasson, Institute for Theoretical Physics, Ruhr-University, Germany Tid: Måndag den 19 december 2011 kl 10.00 Plats: Sal C, Rymdcampus i Kiruna, Luleå tekniska universitet</p

Modeling the Lunar plasma wake

This thesis discusses the solar wind interaction with the Moon and the formation of the lunar plasma wake from a kinetic perspective. The Moon is essentially a non-conducting body which has a tenuous atmosphere and no global magnetic fields. The solar wind plasma impacts directly the lunar day-side and is absorbed by the lunar surface. This creates a plasma void and forms a wake at the night side of the Moon.We study the properties and structure of the lunar wake for typical solar wind conditions using a three-dimensional hybrid plasma solver. Also, we study the solar wind proton velocity space distribution functions at close distances to the Moon in the lunar wake and investigate the effects of lunar surface plasma absorption and non-isothermal solar wind velocity space distribution functions on the solar wind protons there.Finally, we compare the simulation results with the observations and show that a hybrid model of plasma can explain the kinetic aspects of the lunar wake and we investigate the effects of the lunar surface plasma absorption and non-isothermal solar wind velocity distribution on the solar wind proton properties there.Godkänd; 2011; 20111114 (shafat); LICENTIATSEMINARIUM Ämnesområde: Rymdteknik/Space Engineering Examinator: Docent Mats Holmström, IRF Kiruna Diskutant: Senior Scientist Bengt Eliasson, Institute for Theoretical Physics, Ruhr-University, Germany Tid: Måndag den 19 december 2011 kl 10.00 Plats: Sal C, Rymdcampus i Kiruna, Luleå tekniska universitet</p

Kinetic Modeling of the Solar Wind Plasma Interaction with the Moon

The main purpose of this research is to understand various aspects of the solar wind plasma interaction with the Earth's Moon by the means of kinetic computer simulations. The Moon is essentially a non-conducting object, that has a tenuous atmosphere and no global magnetic field. Then the solar wind plasma impacts the lunar surface, where it is absorbed or neutralized for the most part. On average about 10% of the solar wind protons reflect in charge form from lunar crustal magnetization and up to 20% reflect from the lunar surface as neutral atoms.First we consider the Moon to be a perfect plasma absorber and we study the global effects of the solar wind plasma interaction with the Moon using a three-dimensional self-consistent hybrid model. We show that due to the plasma absorption in the lunar dayside, a void region forms behind the Moon and a plasma wake forms downstream. Then we study different parameters that control the lunar wake, discuss various mechanisms that fill in the wake, and compare our simulations with observations. We also discuss the effects of lunar surface plasma absorption on the solar wind proton velocity space distribution at close distances to the Moon in the lunar wake. Moreover, we show that three current systems form in the wake that enhance the magnetic fields in the central wake, depress the fields in the surrounding areas, and confine the fields and plasma perturbations within a Mach cone. Finally we study the effects of protons reflected from lunar crustal magnetic fields on the global lunar plasma environment. We show that the reflected protons interact with the solar wind plasma, compress the fields and plasma upstream in the lunar dayside and downstream outside the Mach cone. The conclusion of this thesis work is that the solar wind plasma interaction with the Moon is dynamic and complex. This is, however, due to the kinetic nature of this interaction because of the scales of the interaction regions where the Magnetohydrodynamics (fluid) approach cannot address the detailed physics. This reveals the importance of kinetic modeling to understand this interaction. The results of this study will feed forward to human space exploration, kinetic theories of plasma interaction with airless bodies, and fundamental plasma physics processes.Godkänd; 2014; 20140325 (shafat); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Shahab Fatemi Ämne: Rymdteknik/Space Technology Avhandling: Kinetic Modeling of the Solar Wind Plasma Interaction with the Moon Opponent: Lektor Geraint Jones, Mullard Space Science Laboratory, Department of Space & Climate Physics, University College London, Dorking, Surrey Ordförande: Docent Mats Holmström, Avd för rymdteknik, Institutionen för system- och rymdteknik, Luleå tekniska universitet/Institutet för rymdfysik, Kiruna Tid: Torsdag den 22 maj 2014, kl 10.00 Plats: Aula, Institutet för rymdfysik, campus Kiruna, Luleå tekniska universite

Computing, visualizing and analyzing ion trajectories

The motion, velocities and trajectories of ions, and the effect of different electromagnetic field conditions on their motion are analyzed in detail. A numerical method is chosen to be used in a model to simulate ion trajectories in uniform and non-uniform electromagnetic fields. The outputs are stored in a file format which can be visualized using different software packages. Ion trajectories and their response to solar wind magnetic field and induced electric field are studied using the simulation model. Since this model can be applied to any solar wind condition, the Earth's moon environment is chosen as a real example for ion trajectories. After an analysis of the interaction of solar wind with the moon, a computational model for simulating its interaction with any other body is introduced. The outputs of this model are used to study ion trajectories at the moon wake. Finally, trajectories and velocities of ions coming from the moon's surface towards an observer orbiting the moon (in conditions of uniform electromagnetic field) are studied, and results for different observer positions are compared and discussed. This has applications for ion observations from a Lunar orbit.Validerat; 20101217 (root

Impact of radial interplanetary magnetic fields on the inner coma of comet 67P/Churyumov-Gerasimenko : Hybrid simulations of the plasma environment

Context. The direction of the interplanetary magnetic field determines the nature of the interaction between a Solar System object and the solar wind. For comets, it affects the formation of both a bow shock and other plasma boundaries, as well as mass-loading. Around the nucleus of a comet, there is a diamagnetic cavity, where the magnetic field is negligible. Observations by the Rosetta spacecraft have shown that, most of the time, the diamagnetic cavity is located within a solar-wind ion cavity, which is devoid of solar wind ions. However, solar wind ions have been observed inside the diamagnetic cavity on several occasions. Understanding what determines whether or not the solar wind can reach the diamagnetic cavity also advances our understanding of cometsolar wind interaction in general. Aims. We aim to determine the influence of an interplanetary magnetic field directed radially out from the Sun that is, parallel to the solar wind velocity on the cometsolar wind interaction. In particular, we explore the possibility of solar wind protons entering the diamagnetic cavity under radial field conditions. Methods. We performed global hybrid simulations of comet 67P/Churyumov-Gerasimenko using the simulation code Amitis for two different interplanetary magnetic field configurations and compared the results to observations made by the Rosetta spacecraft. Results. We find that, when the magnetic field is parallel to the solar wind velocity, no bow shock forms and the solar wind ions are able to enter the diamagnetic cavity. A solar wind ion wake still forms further downstream in this case. Conclusions. The solar wind can enter the diamagnetic cavity if the interplanetary magnetic field is directed radially from the Sun, and this is in agreement with observations made by instruments on board the Rosetta spacecraft

Impact of radial interplanetary magnetic fields on the inner coma of comet 67P/Churyumov-Gerasimenko : Hybrid simulations of the plasma environment

Context. The direction of the interplanetary magnetic field determines the nature of the interaction between a Solar System object and the solar wind. For comets, it affects the formation of both a bow shock and other plasma boundaries, as well as mass-loading. Around the nucleus of a comet, there is a diamagnetic cavity, where the magnetic field is negligible. Observations by the Rosetta spacecraft have shown that, most of the time, the diamagnetic cavity is located within a solar-wind ion cavity, which is devoid of solar wind ions. However, solar wind ions have been observed inside the diamagnetic cavity on several occasions. Understanding what determines whether or not the solar wind can reach the diamagnetic cavity also advances our understanding of cometsolar wind interaction in general. Aims. We aim to determine the influence of an interplanetary magnetic field directed radially out from the Sun that is, parallel to the solar wind velocity on the cometsolar wind interaction. In particular, we explore the possibility of solar wind protons entering the diamagnetic cavity under radial field conditions. Methods. We performed global hybrid simulations of comet 67P/Churyumov-Gerasimenko using the simulation code Amitis for two different interplanetary magnetic field configurations and compared the results to observations made by the Rosetta spacecraft. Results. We find that, when the magnetic field is parallel to the solar wind velocity, no bow shock forms and the solar wind ions are able to enter the diamagnetic cavity. A solar wind ion wake still forms further downstream in this case. Conclusions. The solar wind can enter the diamagnetic cavity if the interplanetary magnetic field is directed radially from the Sun, and this is in agreement with observations made by instruments on board the Rosetta spacecraft