检索结果-内蒙古大学图书馆

arXiv 2023年

作者： Franken, Arnout Caliaro, Martino Cifani, Paolo Geurts, Bernard Multiscale Modelling and Simulation Department of Applied Mathematics Faculty EEMCS University of Twente PO Box 217 Enschede7500 AE Netherlands Gran Sasso Science Institute Viale F. Crispi 7 L’Aquila67100 Italy Multiscale Physics Center for Computational Energy Research Department of Applied Physics Eindhoven University of Technology PO Box 513 Eindhoven5600 MB Netherlands

In this work, we consider a Shallow-Water Quasi Geostrophic equation on the sphere, as a model for global large-scale atmospheric dynamics. This equation, previously studied by Verkley [2009] and Schubert et al. [2009], possesses a rich geometric structure, called Lie-Poisson, and admits an infinite number of conserved quantities, called Casimirs. In this paper, we develop a Casimir preserving numerical method for long-time simulations of this equation. The method develops in two steps: firstly, we construct an N-dimensional Lie-Poisson system that converges to the continuous one in the limit N → ∞;secondly, we integrate in time the finite-dimensional system using an isospectral time integrator, developed by Modin and Viviani [2020]. We demonstrate the efficacy of this computational method by simulating a flow on the entire sphere for different values of the Lamb parameter. We particularly focus on rotation-induced effects, such as the formation of jets. In agreement with shallow water models of the atmosphere, we observe the formation of robust latitudinal jets and a decrease in the zonal wind amplitude with latitude. Furthermore, spectra of the kinetic energy are computed as a point of reference for future studies. Copyright © 2023, The Authors. All rights reserved.

关键词： Kinetic energy

来源：评论

学校读者我要写书评

暂无评论

Color-avoiding percolation in edge-colored Erdős–Rényi graphs

arXiv

引用

arXiv 2022年

作者： Ráth, Balázs Varga, Kitti Fekete, Panna Tímea Molontay, Roland Afréd Rényi Institute of Mathematics Hungary Department of Stochastics Institute of Mathematics Budapest University of Technology and Economics Hungary ELKH-BME Stochastics Research Group Chile Department of Computer Science and Information Theory Faculty of Electrical Engineering and Informatics Budapest University of Technology and Economics Hungary ELKH-ELTE Egerváry Research Group Hungary Department of Applied Analysis and Computational Mathematics Eötvös Loránd University Hungary

We study a variant of the color-avoiding percolation model introduced by Krause et al., namely we investigate the color-avoiding bond percolation setup on (not necessarily properly) edge-colored Erd̋ os–Rényi random graphs. We say that two vertices are color-avoiding connected in an edge-colored graph if after the removal of the edges of any color, they are in the same component in the remaining graph. The color-avoiding connected components of an edge-colored graph are maximal sets of vertices such that any two of them are color-avoiding connected. We consider the fraction of vertices contained in color-avoiding connected components of a given size as well as the fraction of vertices contained in the giant color-avoiding connected component. Under some mild assumptions on the color-densities, we prove that these quantities converge and the limits can be expressed in terms of probabilities associated to edge-colored branching process trees. We provide explicit formulas for the limit of the normalized size of the giant color-avoiding connected component, and in the two-colored case we also provide explicit formulas for the limit of the fraction of vertices contained in color-avoiding connected components of a given size. Copyright © 2022, The Authors. All rights reserved.

关键词： Color

来源：评论

学校读者我要写书评

暂无评论

Methods of Multi-Threshold Decoders Use in Mimo Systems And Methods of Assessing Their Performance

Methods of Multi-Threshold Decoders Use in Mimo Systems And ...

引用

Innovative Approaches in Smart Technologies (ISAS), International Symposium on

作者： Gennady Ovechkin Dina Satybaldina Zhuldyz Sailaukyzy Gulmira Danenova Nurlan Tashatov Department of Computational and Applied Mathematics Ryazan State Radio Engineering University Ryazan Russia Research Institute of Information Security and Cryptology L.N. Gumilyov Eurasian National University Astana Kazakhstan Department of Information Technology and Security Abylkas Saginov Karaganda Technical University Karaganda Kazakhstan Department of Information Security L.N. Gumilyov Eurasian National University Astana Kazakhstan

ISBN: (数字)9798331540104

ISBN: (纸本)9798331540111

This paper discusses use of multi-threshold decoders in the Multiple Input Multiple Output systems with fading radio channels. The main attention is paid to the problems of implementation of the multi-threshold decoders and performance, with a focus on preserving low complexity, which is critically important for achieving high speed of decoding. In modern communication systems, where data communication rates reach dozens and hundreds of Gbit/sec, decoding efficiency becomes a determinant in ensuring stable and reliable information transfer. The obtained results have shown that multi-threshold decoders due to its ability to almost optimally decode even very long codes with low computational complexity ensures high efficiency in channels with different types of fading, including multipath channels with intersymbol influence, when it is used jointly with the orthogonal frequency division multiplexing. Under these conditions, many noise-resistant codes are unfit for service due to their small length, which highlights the multi-threshold decoders advantages. These results confirm the possibility of multi-threshold decoders application in modern high-speed systems of digital data communication with complex nature of errors.

关键词： Codes OFDM Rician channels Line-of-sight propagation Rayleigh channels Decoding Error correction Data communication Reliability Multipath channels

来源：评论

学校读者我要写书评

暂无评论

Strong Polarization of a J=1/2 to 1/2 Transition Arising from Unexpectedly Large Quantum Interference

引用

Physical Review Letters 2023年第11期130卷 113001-113001页

作者： Nobuyuki Nakamura Naoki Numadate Simpei Oishi Xiao-Min Tong Xiang Gao Daiji Kato Hirokazu Odaka Tadayuki Takahashi Yutaka Tsuzuki Yuusuke Uchida Hirofumi Watanabe Shin Watanabe Hiroki Yoneda Institute for Laser Science The University of Electro-Communications Tokyo 182-8585 Japan Center for Computational Sciences University of Tsukuba Ibaraki 305-8573 Japan Institute for Applied Physics and Computational Mathematics Beijing 100088 China National Institute for Fusion Science Toki Gifu 509-5292 Japan Interdisciplinary Graduate School of Engineering Sciences Kyushu University Fukuoka 816-8580 Japan Department of Physics The University of Tokyo Tokyo 113-0033 Japan Kavli Institute for the Physics and Mathematics of the Universe (WPI) Institutes for Advanced Study (UTIAS) The University of Tokyo Chiba 277-8583 Japan Department of Physics School of Science and Technology Tokyo University of Science Chiba 278-8510 Japan Center of Applied Superconductivity and Sustainable Energy Research Chubu University Aichi 487-8501 Japan Institute of Space and Astronautical Science Japan Aerospace Exploration Agency Kanagawa 252-5210 Japan RIKEN Nishina Center Saitama 351-0198 Japan

We experimentally show that the 1s22s22p1/2−1s2s22p1/22 transition in Pb77+ emitted in dielectronic recombination of Pb78+ is strongly polarized, although it is an intrinsically unpolarized J=1/2 to 1/2 transition. This unanticipated polarization is shown to be due to quantum interference with radiative recombination. The interference effect has been studied on an asymmetric resonance profile but has never been studied on polarization. In this Letter, we show that the effect on polarization can arise from a different cross term than that responsible for asymmetry, resulting in unexpectedly large polarization even for a nearly symmetric resonance suggesting a small interference.

关键词： Relativistic & quantum electrodynamic effects in atoms, molecules,& ions Relativistic heavy-ion collisions Ions Polarization

来源：评论

学校读者我要写书评

暂无评论

Projectile and target excitation in He^(+)+He collisions at intermediate energies

引用

Matter and Radiation at Extremes 2021年第1期6卷 31-36页

作者： Junwen Gao Zhimin Hu Yong Wu Jianguo Wang Nicolas Sisourat Alain Dubois Laser Fusion Research Center China Academy of Engineering Physics621900 MianyangChina Institute of Applied Physics and Computational Mathematics 100088 BeijingChina Center for Applied Physics and Technology HEDPSand School of PhysicsPeking University100871 BeijingChina Sorbonne Universite CNRSLaboratoire de Chimie Physique-Matiere et RayonnementF-75005 ParisFrance

We present ab initio calculations of cross sections for projectile and target excitation occurring in the course of He^(+)+He collisions using a threeactive-electron semiclassical nonperturbative *** impact energies ranging from 1 keV to 225 keV/u are *** results of our calculations agree well with available measurements for both projectile and target excitation in the respective overlapping energy regions.A comparison of our results with those of other theoretical calculations further demonstrates the importance of a nonperturbative approach that includes a sufficient number of ***,it is found that the cross sections for target excitation into singlet states show a valley centered at about 25 keV/u,resulting from competition with electron transfer to singlet projectile *** contrast,the cross sections for target excitation into triplet states do not exhibit any such structures.

关键词： excitation singlet states

来源：评论

学校读者我要写书评

暂无评论

Ro-vibrational quenching calculations of C−2 in collision with H2

arXiv

引用

arXiv 2024年

作者： Giri, Kousik Mant, Barry Gianturco, Franco A. Wester, Roland Franz, Jan Biswas, Rupayan Lourderaj, Upakarasamy Sathyamurthy, Narayanasami Department of Computational Sciences Central University of Punjab Punjab Bathinda151401 India Institüt für Ionenphysik und Angewandte Physik Universität Innsbruck Technikerstr. 25 Innsbruck6020 Austria Institute of Physics and Applied Computer Science Faculty of Applied Physics and Mathematics Gdańsk University of Technology ul. Narutowicza 11/12 Gdańsk80-233 Poland Bhubaneswar OCC of Homi Bhabha National Institute Odisha Khurda752050 India Indian Institute of Science Education and Research SAS Nagar Punjab Mohali140306 India

The molecular anion C−2 has been of interest in the last few years as a candidate for laser cooling due to its electronic structure and favourable branching ratios to the ground electronic and vibrational state. Molecular hydrogen has been used by the Wester group in Innsbruck as a buffer gas to cool the molecule’s internal ro-vibrational motion. In the present work, we generate a new, five dimensional (5D) interaction potential for the system by considering the H2 as a rigid rotor and the C−2 as a rotating-vibrating diatomic molecule. We thereafter calculate the cross sections and rate coefficients for ro-vibrational inelastic collisions of C−2 with both para- and ortho-H2 on this new 5D ab initio potential energy surface using quantum scattering theory for the dynamics. The rates for vibrational quenching are obtained over the range of temperatures which covers the single value measured by the experiments. A comparison is also made with the earlier results using a simpler 3D interaction potential. Furthermore, para-H2 is found to be more efficient than ortho-H2 (with or without undergoing rotational excitation) in cooling C−2. The rate coefficients for cooling the anions has been computed by appropriately weighting the ortho- and para-H2 and compared with the available experimental result at 20 K. When the vibrational de-excitation rate coefficients are taken to be the ones not causing any concurrent rotational excitations in the final C−2 anions, the properly averaged results are found to get smaller and to become very close to the experimental measurements. The implications of these new results for laser cooling of C−2 are analyzed and discussed. © 2024, CC BY.

关键词： Molecules

来源：评论

学校读者我要写书评

暂无评论

Electron-rotation coupling in UV photodissociation of aligned diatomics

引用

Physical Review research 2022年第1期4卷 013066-013066页

作者： Yan Rong Liu Victor Kimberg Yong Wu Jian Guo Wang Oriol Vendrell Song Bin Zhang School of Physics and Information Technology Shaanxi Normal University Xi'an 710119 China Theoretical Chemistry and Biology Royal Institute of Technology Stockholm 10691 Sweden International Research Center of Spectroscopy and Quantum Chemistry Siberian Federal University – IRC SQC 660041 Krasnoyarsk Russia Institute of Applied Physics and Computational Mathematics Beijing 100088 China Center for Applied Physics and Technology Peking University Beijing 100084 China Theoretical Chemistry Institute of Physical Chemistry Heidelberg University 69120 Heidelberg Germany

We investigate the effect of electron-rotation coupling (R−Ω coupling) on fs UV photodissociation dynamics of aligned diatomic molecules. We consider the showcase of ground-state MgH+ (1Σ+) pumped by an fs IR pulse, which initiates rotational dynamics leading to field-free molecular alignment. A time-delayed fs UV pulse probes the degree of alignment of the rotational wave packet in the framework of photodissociation spectroscopy. The molecular alignment correlates directly with the angular distribution of the photofragments in the dissociative 1Π state, as it is shown in our simulations comparing the cases when the R−Ω coupling is included and ignored. We show how the angular distribution of the photofragment is strongly affected by the R−Ω coupling at various delay times with specific molecular alignment. It was shown that increases of the fs UV pulse intensity and the degree of alignment enhance the effect of R−Ω coupling on the angular distribution of the photofragments. On the contrary, an increase of the initial temperature tends to reduce the effect of R−Ω coupling, which is explained by the fact that such an effect turns smaller as the increasing of magnetic state |M0| for each initial rotational state J0; furthermore, higher excited rotational state J0 contains more magnetic states M0, and the results have been averaged over all degenerated M0 states.

关键词： Atomic & molecular processes in external fields Photodissociation

来源：评论

学校读者我要写书评

暂无评论

Analysis and Fabrication of a Compact CPW-Fed Planar Printed UWB Antenna Using Isola Tera MT (R) Substrate for Medical Applications 3rd

Analysis and Fabrication of a Compact CPW-Fed Planar Printed...

引用

3rd International Conference on Energy Systems, Drives and Automations, ESDA 2020

作者： Lakrit, Soufian Das, Sudipta Chowdhury, Apurba MoussaLabbadi Madhav, B.T.P. Applied Mathematics and Information Systems Laboratory EST of Nador Mohammed First University Oujda Morocco Department of Electronics & Communication Engineering IMPS College of Engineering & Technology W.B Malda India Mallabhum Institute of Polytechnic Bishnupur Bankura India Engineering for Smart and Sustainable Systems Research Center EMI Mohammed V University in Rabat Rabat Morocco Department of Electronics and Communication Engineering Koneru Lakshmaiah Education Foundation AP Guntur India

ISBN: (纸本)9789811672736

The purpose of this research work is to propose a compact and efficient CPW-Fed ultra-wideband (UWB) antenna suitable for integration in microwave imaging systems for early detection of breast cancer. The suggested structure consists of a coplanar waveguide monopole UWB antenna printed on Isola substrate of volume 44 × 38 × 0.762 mm3. The designed structure is simulated and analyzed using both CST Microwave Studio® and ANSYS HFSS EM simulation software. The Simulation results show frequency band coverage from 1.48 to 17.20 GHz, having a large impedance bandwidth of 15.72 GHz. A prototype of the antenna is fabricated and tested with a network analyzer. The experimental result confirms the large UWB resonance expanding from 1.87 to 16.23 GHz for VSWR © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Ultra-wideband (UWB)

来源：评论

学校读者我要写书评

暂无评论

Public Goods Games in Disease Evolution and Spread

arXiv

引用

arXiv 2024年

作者： Morison, Christo Fic, Mallgorzata Marcou, Thomas Mohamadichamgavi, Javad Antón, Javier Redondo Sayyar, Golsa Stein, Alexander Bastian, Frank Krakovská, Hana Krishnan, Nandakishor Pires, Diogo L. Satouri, Mohammadreza Thomsen, Frederik J. Tjikundi, Kausutua Ali, Wajid School of Mathematical Sciences Queen Mary University of London London United Kingdom Department of Theoretical Biology Max Planck Institute for Evolutionary Biology Plön Germany Center for Computational and Theoretical Biology University of Würzburg Würzburg Germany Centre for Mathematical Biology University of South Bohemia České Budějovice Czech Republic Institute of Applied Mathematics and Mechanics University of Warsaw Warsaw Poland Department of Computer Science University of Turin Turin Italy Bolyai Institute University of Szeged Szeged Hungary Evolutionary Dynamics Group Centre for Cancer Genomics and Computational Biology Barts Cancer Institute Queen Mary University of London London United Kingdom School of Mathematical Sciences University College Cork Cork Ireland Section for Science of Complex Systems Medical University of Vienna Vienna Austria Complexity Science Hub Vienna Vienna Austria HUN-REN Centre for Ecological Research Institute of Evolution Budapest Hungary Department of Mathematics City University of London London United Kingdom Institute for Health Systems Science Faculty of Technology Policy and Management Delft University of Technology Delft Netherlands Institute of Applied Mathematics Delft University of Technology Delft Netherlands ISI Foundation Turin Italy Department of Mathematical Sciences University of Liverpool Liverpool United Kingdom

Cooperation arises in nature at every scale, from within cells to entire ecosystems. In the framework of evolutionary game theory, public goods games (PGGs) are used to analyse scenarios where individuals can cooperate or defect, and can predict when and how these behaviours emerge. However, too few examples motivate the transferal of knowledge from one application of PGGs to another. Here, we focus on PGGs arising in disease modelling of cancer evolution and the spread of infectious diseases. We use these two systems as case studies for the development of the theory and applications of PGGs, which we succinctly review and compare. We also posit that applications of evolutionary game theory to decision-making in cancer, such as interactions between a clinician and a tumour, can learn from the PGGs studied in epidemiology, where cooperative behaviours such as quarantine and vaccination compliance have been more thoroughly investigated. Furthermore, instances of cellular-level cooperation observed in cancers point to a corresponding area of potential interest for modellers of other diseases, be they viral, bacterial or otherwise. We aim to demonstrate the breadth of applicability of PGGs in disease modelling while providing a starting point for those interested in quantifying cooperation arising in healthcare. © 2024, CC BY.

关键词： Diseases

来源：评论

学校读者我要写书评

暂无评论

Existence and regularity of inverse problem for the nonlinear fractional Rayleigh-Stokes equations

Existence and regularity of inverse problem for the nonlinea...

引用

作者： Tran Bao, Ngoc Nguyen Hoang, Luc Vo Van, Au Nguyen, Huy Tuan Zhou, Yong Institute of Research Development Duy Tan University Da Nang550000 Viet Nam Department of Mathematics and Computer Science University of Science Ho Chi Minh City Viet Nam Vietnam National University Ho Chi Minh City Viet Nam Applied Analysis Research Group Faculty of Mathematics Statistics Ton Duc Thang University Ho Chi Minh City Viet Nam Faculty of Information Technology Macau University of Science Technology 999078 China Faculty of Mathematics Computational Science Xiangtan University Hunan411105 China

This paper investigates an inverse problem for fractional Rayleigh-Stokes equations with nonlinear source. The fractional derivative in time is taken in the sense of Riemann-Liouville. The proposed problem has many applications in some non-Newtonian fluids. We obtain some results on the existence and regularity of mild solutions. © 2020 John Wiley & Sons, Ltd.

关键词： Inverse problems

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：