333 research outputs found
Прогнозирование стабильной композиции для высокоэнтропийных тугоплавких сплавов
No full textThe common approach for evaluation of stability of multicomponent substitutional solid solutions using thermodynamic, mechanical, and topological parameters of the constituent elements is developed. The high-temperature systems based on refractory elements (W, Ta, Mo, Nb, V, Ti, Zr, Hf, Cr) are investigated using this approach. Optimal compositions for high-entropy alloys are obtained, and influence of various factors in the formation of stable alloys is described. As shown, the most resistant alloys have non-equiatomic element-contents’ ratios. The agreement between element distribution in experimental alloys and predicted stable compositions are obtained for the W— Ta—Mo—Nb and W—Ta—Mo—Nb—V systems.Розроблено загальний підхід для оцінки стабільности багатокомпонентних твердих розчинів заміщення з використанням термодинамічних, механічних і топологічних параметрів елементів, що їх складають. Високотемпературні системи, що містять тяжкотопкі елементи (W, Ta, Mo, Nb, V, Ti, Zr, Hf, Cr), були досліджені за допомогою цього підходу. Одержано оптимальні склади для високоентропійних стопів і описано вплив різних чинників у формуванні стабільних стопів. Показано, що найбільш стійкі стопи мають нееквіатомне співвідношення складів елементів. Для систем W—Ta—Mo—Nb і W—Ta—Mo—Nb—V було одержано узгодженість між розподілами елементів в експериментальних стопах і прогнозованих стабільних композиціях.Разработан общий подход для оценки стабильности многокомпонентных твёрдых растворов замещения с использованием термодинамических, механических и топологических параметров составляющих их элементов. Высокотемпературные системы, состоящие из тугоплавких элементов (W, Ta, Mo, Nb, V, Ti, Zr, Hf, Cr), были исследованы с использованием этого подхода. Получены оптимальные составы для высокоэнтропийных сплавов и описано влияние различных факторов при формировании стабильных сплавов. Показано, что наиболее стабильные сплавы характеризуются неэквиатомным отношением составов элементов. Для систем W— Ta—Mo—Nb и W—Ta—Mo—Nb—V было получено согласие между распределениями элементов в экспериментальных сплавах и предсказанных стабильных композициях
Magnetohydrodynamic turbulence in a Hartmann duct flow at finite magnetic Reynolds number
No full textThe dynamics of turbulent flow at finite magnetic Reynolds numbers can be very complex due to the coupled nature of the evolution equations for the flow and magnetic fields. In this regime, the Hartmann flow in a straight rectangular duct with streamwise periodicity is studied with the help of direct numerical simulations (DNS) and the effect of magnetic Reynolds number on turbulent statistics is quantified by comparing the results with the numerical results obtained using the quasistatic approximation
The Phenomenon of the Crowd in Russian Psychology: V.K. Sluchevsky's Concept
Get PDFThe article describes the concept of the crowd proposed by a Russian lawyer and public figure V.K. Sluchevsky (1893). It focuses on its principal differences from other concepts of this initial period and reveals the moral potential of Sluchevsky's views in psychology. Among the issues that were of particular interest to the author of one of the first concepts of spontaneous groups were the specifics of the crowd as a social association, features of the crowd, factors of its formation, changes in personality of individuals, and problems concerning the prevention and punishment of mass crimes
Nonlinear Fourier transform of time-limited and one-sided signals
No full textIn this article, we study the properties of the nonlinear Fourier spectrum in order to gain better control of the temporal support of the signals synthesized using the inverse nonlinear Fourier transform. In particular, we provide necessary and sufficient conditions satisfied by the nonlinear Fourier spectrum such that the generated signal has a prescribed support. In our exposition, we assume that the support is a simply connected domain that is either a bounded interval or the half-line, which amounts to studying the class of signals which are either time-limited or one-sided, respectively. Further, it is shown that the analyticity properties of the scattering coefficients of the aforementioned classes of signals can be exploited to improve the numerical conditioning of the differential approach of inverse scattering. Here, we also revisit the integral approach of inverse scattering and provide the correct derivation of the so called Töplitz inner-bordering algorithm. Finally, we conduct extensive numerical tests in order to verify the analytical results presented in the article. These tests also provide us an opportunity to compare the performance of the two aforementioned numerical approaches in terms of accuracy and complexity of computations.Accepted Author ManuscriptTeam Raf Van de Pla
Efficient Nonlinear Fourier Transform algorithms of orderfFour on equispaced grid
No full textWe explore two classes of exponential integrators, in this letter, to design the nonlinear Fourier transform (NFT) algorithms with a convergence order of four on an equispaced grid. The integrating factor-based method in the class of the Runge-Kutta methods yields algorithms with complexity O(N\log2N) (where N is the number of samples of the signal), which have superior accuracy-complexity tradeoff than any of the fast methods known currently. The integrators based on Magnus series expansion, namely, standard and commutator-free Magnus methods yield the algorithms of complexity O(N2) that have superior error behavior than that of the fast methods.Accepted Author ManuscriptTeam Raf Van de Pla
Higher order convergent fast nonlinear Fourier transform
No full textIt is demonstrated in this letter that linear multistep methods for integrating ordinary differential equations can be used to develop a family of fast forward scattering algorithms with higher orders of convergence. Excluding the cost of computing the discrete eigenvalues, the nonlinear Fourier transform (NFT) algorithm thus obtained has a complexity of O(KN+CpNlog2N) such that the error vanishes as mathop O(N-p) where p ϵ {1,2,3,4} and K is the number of eigenvalues. Such an algorithm can be potentially useful for the recently proposed NFT-based modulation methodology for optical fiber communication. The exposition considers the particular case of the backward differentiation formula (Cp=p3) and the implicit Adams method (Cp=(p-13,p>1) of which the latter proves to be the most accurate family of methods for fast NFT.Accepted Author ManuscriptTeam Raf Van de Pla
Effect of Chemical Composition and Heat Treatment on the Shape Memory Parameters in the TiNi-Me Alloys
No full textThe TiNi-Me shape memory alloy parameters (namely, phase transformation "strength yield"
recoverable strain, reversion stress, material hardness) have been investigated as a function of the chemical
composition, heat treatment regimes and deformation condition. These parameters are found to be structurally sensitive ones both to the macroscopic and microscopic structure of the material. Their response to heat treatment regimes is usually non-homogeneous function of the aging temperature and time variation.
Effects of doping and secondary particle precipitation are of great importance. Some recommendations for the
choice of the SMA chemical composition and final heat treatment regime can be proposed
Exact solution of the Zakharov–Shabat scattering problem for doubly-truncated multisoliton potentials
No full textRecent studies have revealed that multisoliton solutions of the nonlinear Schrödinger equation, as carriers of information, offer a promising solution to the problem of nonlinear signal distortions in fiber optic channels. In any nonlinear Fourier transform based transmission methodology seeking to modulate the discrete spectrum of the multisolitons, choice of an appropriate windowing function is an important design issue on account of the unbounded support of such signals. Here, we consider the rectangle function as the windowing function for the multisolitonic signal and provide a recipe for computing the exact solution of the associated Zakharov–Shabat (ZS) scattering problem for the windowed/doubly-truncated multisoliton potential. The idea consists in expressing the Jost solution of the doubly-truncated multisoliton potential in terms of the Jost solution of the original potential. The proposed method allows us to avoid prohibitive numerical computations normally required in order to accurately quantify the effect of time-domain windowing on the nonlinear Fourier spectrum of the multisolitonic signals. Further, the method devised in this work also applies to general type of signals admissible as ZS scattering potential, and, may prove to be a useful tool in the theoretical analysis of such systems.Accepted Author ManuscriptTeam Raf Van de Pla
Development and quality evaluation of shelf stable texturized chicken and egg based spread.
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
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