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Angular Decomposition and Sign Solved propagator of the 2D and 3D Helium Atom Path Integrals

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Journal of Applied Mathematics and Physics 2022年第2期10卷 538-557页

作者： Emmanouil George Thrapsaniotis Athens Greece

In the present paper on the one hand we apply the central limit theorem to the solution of the sign problem of a path integral of two-interacting particles in potential and give an expression for the sign solved propagator (SSP) derived from that solution and on the other hand we perform the angular decomposition of the path integrals of the 2D and 3D Helium atoms. Finally, we combine those two results and derive the SSPs of the 2D and 3D Helium atoms.

关键词： propagator Angular Decomposition Sign Problem Central Limit Theorem 3D Helium 2D Helium

A Generalized propagator Algorithm for Localization of Non-circular Sources Using Arbitrary Array Geometry

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第2期36卷 339-351页

作者： CAO Renzheng ZHANG Xiaofei The 28th Research Institute China Electronics Technology Group CorporationNanjing 210007P.R.China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China

A propagator-based algorithm for direction of arrival(DOA)estimation of noncoherent one-dimensional(1-D)non-circular sources is presented such as binary phase shift keying(BPSK)and amplitude modulation(AM).The algorithm achieves DOA estimation through searching a 1-D spectrum,which is newly formed on the basis of the rank reduction criterion,and works well without knowledge of the non-circular *** then,a search-free implementation of the algorithm is also developed by using the polynomial rooting *** to the non-circular property,the algorithm can virtually enlarge the array aperture,thus significantly improving its estimation accuracy and enabling it to handle more sources than the number of ***,the algorithm requires no rotational invariance,so it can be applied to arbitrary array geometry and dispense with the high-complexity procedure of the eigen-decomposition of the correlation sample ***,numerical simulations verify the performance and effectiveness of the proposed algorithm.

关键词： direction of arrival(DOA) subspace method rank reduction criterion propagator non-circular source

Evaluation of Different Substrates Compositions for Acclimatization of Tissue Culture Taro Plantlets in a propagator

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Agricultural Sciences 2023年第7期14卷 925-938页

作者： Evelyn Bi Manju Victorine Yaya Fornkwav Irene Bonsiysi Bam Raissa Akwa Tima Department of Crop Production Technology College of Technology University of Bamenda Bamenda Cameroon International Potato Centre (CIP) Yaounde Cameroon Institute of Agricultural Research for Development (IRAD) Bambui Cameroon Department of Management Faculty of Economics and Management Science University of Bamenda Bamenda Cameroon

Taro is cultivated in most Regions of Cameroon and it is affected by taro leaf blight disease since 2010 which has decreased its production. Lack of disease-free planting materials has been a main problem to farmers. This study was carried out at International Institute of Tropical Agriculture (IITA) Yaounde and Institute of Agricultural Research for Development (IRAD) Bambui to assess different substrates for acclimatization of tissue culture taro plantlets in apropagator. No information is available on acclimatization of Cameroonian taro plantlets in different substrates. Taro plantlets from tissue culture were acclimatised in a propagator for six weeks under different substrates, the first substrate consisted of sterile three parts of soil and one part of river sand mixed together (3:1), the second substrate consisted of sterile two parts of soil and two parts of river sand mixed together (2:2), the third substrate consisted of sterile two parts of soil, one part of rice husk and one part of river sand mixed together (2:1:1) and the fourth substrate consisted of sterile one part of soil and three parts of river sand mixed together (1:3). After acclimatisation of the different taroplantlets (Dark green petiole with small leaves (L1), Red petiole with small leaves (L2), Light green petiole with large leaves (L3) and Light green petiole with small leaves (L4) in these four substrates, it was observed that the best growth rate of plant was recorded on substrate sand + soil (1:3). The other substrates showed moderate growth of plants. Substrate sand + soil (1:3) can be recommended for acclimatization of Cameroonian taro plantlets.

关键词： Taro Tissue Culture Plantlets Substrates Acclimatization propagator

Alternative Derivation of the propagator in Polar Coordinates by Feynman's Physical Interpretation of the Characteristic Function

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Communications in Theoretical Physics 2002年第5期38卷 529-532页

作者： QIAN Shang-Wu CHAN King-Man GU Zhi-Yu Physics Department Peking University Beijing 100871 China Physics Department Peking University Beijing 100871 China Physics Department Capital Normal University Beijing 100037 China

This article revisits Feynman's characteristic function, and points out the insight and usefulness of hisphysical interpretation. As an example, the tedious and rather long derivation of the propagator in polar coordinatescan be easily and clearly obtained by merely using Feynman's physical intepretation of the characteristic function andsome well-known results of central force problem.

关键词： Feynman's characteristic function, propagator in polar coordinates

Semiclassical propagator and van Vleck in a mixed position-momentum determinant space

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Chinese Physics B 2006年第5期15卷 919-922页

作者：杨光参 School of Physics and Electronic Information Wenzhou University Wenzhou 325027 China

In this paper a semiclassical propagator in a mixed position-momentum space is derived in the formalism of Maslov＇s multi-dimensional semiclassical theory. The corresponding mixed van Vleck determinant is also given explicitly. The propagator can be used to locally fix semiclassical divergences in singular regions of configuration space. It is shown that when a semicla^sical propagator is transformed from one representation to another, its form is invariant.

关键词： semiclassical theory propagator mixed space

Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields

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Plasma Science and Technology 2019年第9期21卷 1-18页

作者： Hirotake SUGAWARA Division of Electronics for Informatics Graduate School of Information Science and TechnologyHokkaido University

This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well.

关键词： propagator method electron velocity distribution function electron transport coefficients crossed electric and magnetic fields magnetized plasma Boltzmann equation

Dimension decomposition algorithm for multiple source localization using uniform circular array

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Journal of Systems Engineering and Electronics 2023年第3期34卷 650-660页

作者： SU Xiaolong HU Panhe WEI Zhenhua LIU Zhen SHI Junpeng LI Xiang College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China Combat Support College Rocket Force University of EngineeringXi’an 710025China

A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is *** to the fact that the far-field signal can be considered as the state where the range parameter of the nearfield signal is infinite,the algorithm for the near-field source localization is also suitable for estimating the direction of arrival(DOA)of far-field *** decomposing the first and second exponent term of the steering vector,the three-dimensional(3-D)parameter is transformed into two-dimensional(2-D)and onedimensional(1-D)parameter ***,by partitioning the received data,we exploit propagator to acquire the noise ***,the objective function is established and partial derivative is applied to acquire the spatial spectrum of 2-D *** last,the estimated 2-D DOA is utilized to calculate the phase of the decomposed vector,and the least squares(LS)is performed to acquire the range *** comparison to the existing algorithms,the proposed DIDE algorithm requires neither the eigendecomposition of covariance matrix nor the search process of range spatial spectrum,which can achieve satisfactory localization and reduce computational *** are implemented to illustrate the advantages of the proposed DIDE ***,simulations demonstrate that the proposed DIDE method can also classify the mixed far-field and near-field signals.

关键词： source localization parameter estimation uniform circular array(UCA) propagator partial derivative least squares(LS)

Analyticity of the Sine Family with L^P-Maximal Regularity for Second Order Cauchy Problems

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Acta Mathematica Sinica,English Series 2010年第3期26卷 561-568页

作者： Yong Zhong HUANG Meng Cheng WANG School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan 430074 P. R. China

If the second order problem u（t）＋ Bu（t）＋ Au（t） = f（t）, u（0） =u（0） = 0 has L^p-maximal regularity, 1 〈 p 〈 ∞, the analyticity of the corresponding propagator of the sine type is shown by obtaining the estimates of ‖λ（λ^2 ＋ λB ＋ A）^-1‖ and ‖B（λ^2 ＋ λB ＋ A）^-1‖ for λ∈ C with Reλ 〉 ω, where the constant ω≥ 0.

关键词： analyticity second order Cauchy problem maximal regularity propagator

Generalized Aharonov-Bohm plus oscillator system

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Science China Mathematics 1995年第12期38卷 1457-1463页

作者：程学浦黄博文顾之雨钱尚武 Department of Electronics College of Mechanical Engineering Beijing 100020 China Department of Physics Capital Normal University Beijing 100037 China Department of Physics Peking University Beijing 100871 China

A generalized Aboronov-Bohm plus oscillator (ABO) system is worked out. The normalized wave functions and energy eigenvalues for the ABO system are obtained with the path integral method.

关键词： A-B effect ABO system Feynman path integral propagator wavefunction energy eigenvalue.