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Yayın FCC-HH: The hadron collider: future circular collider conceptual design report volume 3(Springer Heidelberg, 2019-07-01) Bayındır, Cihan; Abada, Asmaa; Abbrescia, Marcello; AbdusSalam, Shehu S.In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100TeV. Its unprecedented centre of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries.Yayın Dalgalardan enerji üretme teknolojisinin yirminci yüzyıl başında Türkiye’deki yansımaları üzerine bir çeviri(İstanbul Üniversitesi, 2015-06-01) Bayındır, Ahmet; Bayındır, CihanOkyanus ve deniz dalgalarından enerji üretme fikri 1800’lerin başlarında yaygınlaşmaya başlamıştır. 1973’e gelindiğinde ise bu konuda alınan patent sayısı çok sayıda değişik tasarımla 340’a ulaşmıştır. Günümüzde ise dalga, gelgit, akıntı, sıcaklık farkı, biyolojik ve nükleer bileşenleri kullanma gibi birçok ilkeye dayanan tasarımlar mevcuttur. Bu çalışmada 1911 yılında Şehbal dergisinde dalgalardan enerji üreten iki sistemi tanıtmak için yayınlanan bir yazının çevirisi Osmanlı bilim tarihi araştırmalarına ışık tutması amacıyla sunulmuştur.Yayın Shapes and statistics of the rogue waves generated by chaotic ocean current(International Society of Offshore and Polar Engineers, 2016) Bayındır, CihanIn this study we discuss the shapes and statistics of the rogue (freak) waves emerging due to wave-current interactions. With this purpose, we use a simple governing equation which is a nonlinear Schrödinger equation (NLSE) extended by R. Smith (1976). This extended NLSE accounts for the effects of current gradient on the nonlinear dynamics of the ocean surface near blocking point. Using a split-step scheme we show that the extended NLSE of Smith is unstable against random chaotic perturbation in the current profile. Therefore the monochromatic wave field with unit amplitude turns into a chaotic sea state with many peaks. By comparing the numerical and analytical results, we show that rogue waves due to perturbations in the current profile are in the form of rational rogue wave solutions of the NLSE. We also discuss the effects of magnitude of the chaotic current profile perturbations on the statistics of the rogue wave generation at the ocean surface. The extension term in Smith's extended NLSE causes phase shifts and it does not change the total energy level of the wave field. Using the methodology adopted in this study, the dynamics of rogue wave occurrence on the ocean surface due to blocking effect of currents can be studied. This enhances the safety of the offshore operations and ocean travel.Yayın Rogue waves of the Kundu-Eckhaus equation in a chaotic wave field(American Physical Society, 2016-03-01) Bayındır, CihanIn this paper we study the properties of the chaotic wave fields generated in the frame of the Kundu-Eckhaus equation (KEE). Modulation instability results in a chaotic wave field which exhibits small-scale filaments with a free propagation constant, k. The average velocity of the filaments is approximately given by the average group velocity calculated from the dispersion relation for the plane-wave solution; however, direction of propagation is controlled by the beta parameter, the constant in front of the Raman-effect term. We have also calculated the probabilities of the rogue wave occurrence for various values of propagation constant k and showed that the probability of rogue wave occurrence depends on k. Additionally, we have showed that the probability of rogue wave occurrence significantly depends on the quintic and the Raman-effect nonlinear terms of the KEE. Statistical comparisons between the KEE and the cubic nonlinear Schrodinger equation have also been presented.Yayın Assessment and enhancement of SAR noncoherent change detection of sea-surface oil spills(IEEE, 2018-01) Bayındır, Cihan; Frost, J. David; Barnes, Christopher F.Oil spills are one of the most dangerous catastrophes that threaten the oceans. Therefore, detecting and monitoring oil spills by means of remote sensing techniques that provide large-scale assessments is of critical importance to predict, prevent, and clean oil contamination. In this study, the detection of an oil spill using synthetic aperture radar (SAR) imagery is considered. Detection of the oil spill is performed using change detection algorithms between imagery acquired at different times. The specific algorithms used are the correlation coefficient change statistic and the intensity ratio change statistic algorithms. These algorithms and the probabilistic selection of threshold criteria are reviewed and discussed. A recently offered change detection method that depends on generating change maps of two images in a temporal sequence is used. An initial change map is obtained by cumulatively adding sequences in such a manner that common change areas are excluded and uncommon change areas are included. A final change map is obtained by comparing the first and the last images in the temporal sequence. This method requires at least three images to be employed and can be generalized to longer temporal image sequences. The purpose of this approach is to provide a double-check mechanism to the conventional approach and, thus, reduce the probability of false alarm while enhancing change detection. The algorithms are tested on 2010 Gulf of Mexico oil spill imagery. It is shown that the intensity ratio change statistic is a better tool for identification of the changes due to the oil spill compared to the correlation coefficient change statistic. It is also shown that the proposed method can reduce the probability of false alarm.Yayın A novel nonlinear frequency modulated chirp signal for synthetic aperture radar and sonar imaging(Millî Savunma Üniversitesi, 2016-01-20) Bayındır, CihanIn order to maintain average power levels as well as high range resolution, phasecoded signals are used in radar and sonar signal processing. One of the most commonly used phase-coded signals is the linear frequency modulated chirp waveform. Various nonlinear frequency-modulated chirps are offered as alternatives to linear frequency modulated chirp. In this paper a new nonlinear frequency modulated chirp waveform is proposed. Properties like bandwidths, point spread functions and Fourier transforms are given for the proposed chirp signal. Synthetic imagery for spotlight imaging geometry is reconstructed by using the polar format and Stolt format processing techniques using the linear frequency-modulated (LFM) and proposed nonlinear frequency modulated chirp. Comparisons are presented, and it is shown that proposed waveform can improve the sonar image resolution.Yayın Analytical and numerical aspects of the dissipative nonlinear Schrödinger equation(Işık University Press, 2016-02-15) Bayındır, CihanIn this paper various analytical and numerical aspects of the dissipative nonlinear Schrodinger equation (d-NLS equation) are discussed. Decaying solitary wave type solutions derived by Demiray is reviewed and a new approximate solitary wave type solution of the d-NLS equation is introduced in order to make comparisons. Also a split-step Fourier scheme is proposed for numerical solution of the d-NLS equation and the analytical solutions are compared with the numerical results.Yayın Rogue wavefunctions due to noisy quantum tunneling potentials(Işık University Press, 2017-02-02) Bayındır, CihanIn this paper, we study the effects of white-noised potentials on nonlinear quantum tunneling. We use a split-step scheme to numerically solve the nonlinear Schrodinger equation (NLSE) with a tunneling potential. We consider three different types of potentials, namely; the single rectangular barrier, double rectangular barrier, and triangular barrier. For all these three cases, we show that white-noise given to potentials do not trigger modulation instability for tunneling of the sech type soliton solutions of the NLSE. However, white-noised potentials trigger modulation instability for tunneling of the sinusoidal wavefunctions; thus, such a wavefield turns into a chaotic one with many apparent peaks. We argue that peaks of such a field may be in the form of rational rogue wave solutions of the NLSE. Our results can be used to examine the effects of noise on quantum tunneling. Since a rogue wavefunction means a higher probability of the tunneling particle to be at a given (x,t) coordinate, our results may also be used for developing the quantum science and technology with many possible applications including but are not limited to increasing the resolution and efficiency of scanning tunneling microscopes, enhancing proton tunneling for DNA mutation and enhancing superconducting properties of junctions.Yayın Compressive spectral method for the simulation of the nonlinear gravity waves(Nature Publishing Group, 2016-02-25) Bayındır, CihanIn this paper an approach for decreasing the computational effort required for the spectral simulations of the fully nonlinear ocean waves is introduced. The proposed approach utilizes the compressive sampling algorithm and depends on the idea of using a smaller number of spectral components compared to the classical spectral method. After performing the time integration with a smaller number of spectral components and using the compressive sampling technique, it is shown that the ocean wave field can be reconstructed with a significantly better efficiency compared to the classical spectral method. For the sparse ocean wave model in the frequency domain the fully nonlinear ocean waves with Jonswap spectrum is considered. By implementation of a high-order spectral method it is shown that the proposed methodology can simulate the linear and the fully nonlinear ocean waves with negligible difference in the accuracy and with a great efficiency by reducing the computation time significantly especially for large time evolutions.Yayın Compressive spectral renormalization method(Işık University Press, 2018-09-09) Bayındır, CihanIn this paper a novel numerical scheme for finding the sparse self-localized states of a nonlinear system of equations with missing spectral data is introduced. As in the Petviashivili's and the spectral renormalization method, the governing equation is transformed into Fourier domain, but the iterations are performed for far fewer number of spectral components (M) than classical versions of the these methods with higher number of spectral components (N). After the converge criteria is achieved for M components, N component signal is reconstructed from M components by using the l(1) minimization technique of the compressive sampling. This method can be named as compressive spectral renormalization (CSRM) method. The main advantage of the CSRM is that, it is capable of finding the sparse self-localized states of the evolution equation(s) with many spectral data missing.
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