Browsing by Publisher "Polish Academy of Sciences"
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Item Measurements of environmental pollution in industrial area using magnetic susceptibility method(Polish Academy of Sciences, 2012) Kucer N.; Sabikoglu I.; Can N.Gaziemir district of Izmir, the Aegean Free Zone, is an industry center of approximately 295 companies that operate in lots of fields such as production, maintenance-repair, trade and that provide 1/3 of total employment in 21 free zones in Turkey. In this study, magnetic susceptibility values of soil samples taking from environment of various factories in Aegean Free Zone have been determined. Magnetic susceptibilities of samples in low and high frequency have been measured by Bartington MS2B magnetic susceptibility measurement device. All of the samples have showed ferromagnetic characteristics and also their pseudosingle-domain structures and super paramagnetic granule additives have been determined by evaluating their graphics connected to frequency.Item Laguerre polynomial solutions of a class of initial and boundary value problems arising in science and engineering fields(Polish Academy of Sciences, 2016) Gürbüz B.; Sezer M.In this study, we consider high-order nonlinear ordinary differential equations with the initial and boundary conditions. These kinds of differential equations are essential tools for modelling problems in physics, biology, neurology, engineering, ecology, economy, astrophysics, physiology and so forth. Each of the mentioned problems are described by one of the following equations with the specific physical conditions: Riccati, Duffing, EmdenFowler, Lane Emden type equations. We seek the approximate solution of these special differential equations by means of a operational matrix technique, called the Laguerre collocation method. The proposed method is based on the Laguerre series expansion and the collocation points. By using the method, the mentioned special differential equations together with conditions are transformed into a matrix form which corresponds to a system of nonlinear algebraic equations with unknown Laguerre coefficients, and thereby the problem is approximately solved in terms of Laguerre polynomials. In addition, some numerical examples are presented to demonstrate the efficiency of the proposed method and the obtained results are compared with the existing results in literature.Item Investigation of the effects of moving targets on hit force in taekwondo(Polish Academy of Sciences, 2016) Kumartasli M.; Üncü I.S.; Çatikkas F.; Akyüz M.; Kilim O.The system to be developed has been designed in order to determine the training levels of the athletes in the field of taekwondo at national and international level and to follow-up the talent development process using computer support. The progression and continuity of hit power and time-dependent performance improvement of an athlete can be measured with interactive impact measurement system. The system determines a random target. It marks the target by blue light. When the light turns on, the athlete reacts accordingly and swiftly by kicking without knowing the light timing. The athlete only needs to know where the light is. Unlike in other training systems, the piston has been able to go back and forth in response to the strike of the athlete by means of a moving hydraulic system. The athlete can be pushed back by opening the piston when his/her performance drops down. The piston strike model is deactivated when the performance of the athlete is above a given threshold value. There will be four operating phases in the mechanism depending on the impact speed of the piston. Moving target robotic system analyses various hits in Taekwondo with the aim to determine hit force and reaction time. After completion of the warming up at the first stage, the athlete will be able to increase the workout level from low to high levels and will try to keep the mechanism behind as much as possible. Moreover, the athlete will be able to compare his/her results with results of others. Using this system, the efficiency of athletes can be easily determined and deficiencies can be resolved.Item Novel metal(II) complexes with bidentate Schiff base ligand: Synthesis, spectroscopic properties and dye decolorization functions(Polish Academy of Sciences, 2016) Karakaya C.; Dede B.; Cicek E.The bidentate Schiff base ligand 4-chloro-2-[1-(4-phenylphenyl)ethylideneamino]phenol and its mononuclear Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. Ligand and metal complexes were characterized by elemental analyses, magnetic susceptibility, molar conductivity, 1H- and 13C-NMR, the Fourier transform infrared, UV-Vis, inductively coupled plasma optical emission spectrometry, and thermogravimetric-differential thermogravimetric studies. The results suggest that the mononuclear complexes have a metal to ligand mole ratio of 1:2 and the metal(II) ions are coordinated with the phenolic oxygen and imine nitrogen atoms. Octahedral structures are proposed for the complexes of the Schiff base ligand. Furthermore, the complexes were checked for their efficiency to decolorize the dye methylene blue. In our experiments we found that metal(II) complexes had an acceptable decolorization efficiency against the dye methylene blue.Item A new computational method based on Laguerre polynomials for solving certain nonlinear partial integro differential equations(Polish Academy of Sciences, 2017) Gürbüz B.; Sezer M.In this study, we consider some nonlinear partial integro-differential equations. Most of these equations are used as mathematical models in many problems of physics, biology, chemistry, engineering, and in other areas. Our main purpose is to propose a new numerical method based on the Laguerre and Taylor polynomials, called matrix collocation method, for the numerical solution of the mentioned nonlinear equations under the initial or boundary conditions. To show the effectiveness of this approach, some examples along with error estimations are illustrated by tables and figures.Item A mathematical model for transporting the arriving passengers from the airport to the city centre(Polish Academy of Sciences, 2017) Akincilar A.In case of considerable traffic congestion in an airport, transportation of passengers to city centre may become a challenging task, since airports are generally located far from the centre. In this study, transportation of passengers, who arrive at an airport, to the city centre has been handled. A mathematical model has been developed, which minimises total costs arising from both, the time passed, while passengers are waiting for a vehicle, and the dispatching of a significant amount of vehicles for transporting the passengers. By utilising the proposed model, in addition to matter of when to dispatch, it is also possible to specify which type of vehicles, and how many of them should be dispatched at each time interval. Ultimately, it is reported that such a plan has a great potential to enhance the productivity.Item Laguerre polynomial solutions of a class of delay partial functional differential equations(Polish Academy of Sciences, 2017) Gürbüz B.; Sezer M.In this study, we develop a novel matrix collocation method based on the Laguerre polynomials to find the approximate solutions of some parabolic delay differential equations with integral terms subject to appropriate initial and boundary conditions. The method reduces the solution of the mentioned equations to the solution of a matrix equation which corresponds to system of algebraic equations with unknown Laguerre coefficients. Besides, the error analysis together with numerical results are performed to illustrate the efficiency of our method computationally.Item Investigation of neutron attenuation through FeB, Fe2B and concrete(Polish Academy of Sciences, 2020) Sariyer D.Neutrons produced in high-energy nuclear facilities are very penetrative and travel deeply through many materials. Neutron shielding slows down the high-energy neutrons to thermal energies and absorbing them with suitable materials is an important problem. Neutron attenuation in the shielding is accomplished through elastic and inelastic scattering reactions. For shielding to be efficient, minimum thickness needs to be achieved. To shield from these neutrons, concrete and iron are important materials. In this study, the neutron attenuation effects through shielding materials (concrete, FeB, and Fe2B) were investigated for various thicknesses of the materials. The high-energy neutrons were generated from the interaction protons with energies of 50–1000 MeV and copper target. Neutron dose rate attenuation curves were determined by using FLUKA Monte Carlo code. The results show that the extent of attenuation related to neutron energy depends on the density and thickness of the shielding material. © 2020 Polish Academy of Sciences. All rights reserved.Item Effect of different materials to concrete as neutron shielding application(Polish Academy of Sciences, 2020) Sariyer D.; Küçer R.Neutron shielding is used to protect personnel and equipment from the effect of neutron radiation. The effective neutron shielding should reduce the neutron energy by elastic and inelastic scattering until they can be absorbed. The interaction of neutron with the matter depends on neutron energy and the density of the shielding material. The best known construction and shielding material is concrete. The composition of concrete has an important effect on its neutron shielding properties. Neutron shielding performance of concrete can be improved by adding different materials such as ferro-boron and iron. In this study, neutron shielding properties of concrete were investigated by adding boron carbide B4C, ferro-boron FeB, and iron Fe in concrete. Neutron dose rate attenuation curves were determined by using FLUKA Monte Carlo code complemented with analytical predictions. The simulation results clearly showed that shielding performance of concrete was enhanced depending on the amounts of additional material and density. © 2020 Polish Academy of Sciences. All rights reserved.