检索结果-内蒙古大学图书馆

arXiv 2024年

作者： Cheng, Erjian Mao, Ning Yang, Xiaotian Song, Boqing Lou, Rui Ying, Tianping Nie, Simin Fedorov, Alexander Bertran, François Ding, Pengfei Suvorov, Oleksandr Zhang, Shu Changdar, Susmita Schnelle, Walter Koban, Ralf Yi, Changjiang Burkhardt, Ulrich Büchner, Bernd Wang, Shancai Zhang, Yang Wang, Wenbo Felser, Claudia Max Planck Institute for Chemical Physics of Solids Dresden01187 Germany School of Physical Science and Technology ShanghaiTech Laboratory for Topological Physics ShanghaiTech University Shanghai201210 China Institute of Physics University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing100190 China Leibniz Institute for Solid State and Materials Research IFW Dresden Dresden01069 Germany Helmholtz-Zentrum Berlin für Materialien und Energie Albert-Einstein-Straße 15 Berlin12489 Germany Joint Laboratory "Functional Quantum Materials" BESSY II Berlin12489 Germany Department of Mechanical Engineering Stanford University StanfordCA94305 United States Synchrotron SOLEIL L'Orme des Merisiers Départementale 128 Saint-Aubin91190 France Department of Physics Key Laboratory of Quantum State Construction and Manipulation Ministry of Education Beijing Key Laboratory of Opto-electronic Functional Materials & Micronano Devices Renmin University of China Beijing100872 China Kyiv Academic University Kyiv03142 Ukraine Max Planck Institute for the Physics of Complex Systems Dresden01187 Germany Institute for Solid State and Materials Physics TU Dresden Dresden01062 Germany Department of Physics and Astronomy University of Tennessee KnoxvilleTN37996 United States Min H. Kao Department of Electrical Engineering and Computer Science University of Tennessee KnoxvilleTN37996 United States

Kagome materials with magnetic frustration in two-dimensional networks are known for their exotic properties, such as the anomalous Hall effect (AHE) with non-collinear spin textures. However, the effects of one-dimensional (1D) spin chains within these networks are less understood. Here, we report a distinctive AHE in the bilayer-distorted kagome material GdTi3Bi4, featuring 1D Gd zigzag spin chains, a one-third magnetization plateau, and two successive metamagnetic transitions. At these metamagnetic transitions, Hall resistivity shows abrupt jumps linked to the formation of stripe domain walls, while within the plateau, the absence of detectable domain walls suggests possible presence of skyrmion phase. Reducing the sample size to a few microns reveals additional Hall resistivity spikes, indicating domain wall skew scattering contributions. Magnetic atomistic spin dynamics simulations reveal that the magnetic textures at these transitions have reverse chirality, explaining the evolution of AHE and domain walls with fields. These results underscore the potential of magnetic and crystal symmetry interplay, and magnetic field-engineered spin chirality, for controlling domain walls and tuning transverse properties, advancing spintronic applications. © 2024, CC BY.

关键词： Chirality

来源：评论

学校读者我要写书评

暂无评论

NTIRE 2023 Quality Assessment of Video Enhancement Challenge

arXiv

引用

arXiv 2023年

作者： Liu, Xiaohong Min, Xiongkuo Sun, Wei Zhang, Yulun Zhang, Kai Timofte, Radu Zhai, Guangtao Gao, Yixuan Cao, Yuqin Kou, Tengchuan Dong, Yunlong Jia, Ziheng Li, Yilin Wu, Wei Hu, Shuming Deng, Sibin Xiao, Pengxiang Chen, Ying Li, Kai Zhao, Kai Yuan, Kun Sun, Ming Cong, Heng Wang, Hao Fu, Lingzhi Zhang, Yusheng Zhang, Rongyu Shi, Hang Xu, Qihang Xiao, Longan Ma, Zhiliang Agarla, Mirko Celona, Luigi Rota, Claudio Schettini, Raimondo Huang, Zhiwei Li, Yanan Wang, Xiaotao Lei, Lei Liu, Hongye Hong, Wei Chuang, Ironhead Lin, Allen Guan, Drake Chen, Iris Lou, Kae Huang, Willy Tasi, Yachun Kao, Yvonne Fan, Haotian Kong, Fangyuan Zhou, Shiqi Liu, Hao Lai, Yu Chen, Shanshan Wang, Wenqi Wu, Haoning Chen, Chaofeng Zhu, Chunzheng Guo, Zekun Zhao, Shiling Yin, Haibing Wang, Hongkui Meftah, Hanene Brachemi Fezza, Sid Ahmed Hamidouche, Wassim Déforges, Olivier Shi, Tengfei Mansouri, Azadeh Motamednia, Hossein Bakhtiari, Amir Hossein Aznaveh, Ahmad Mahmoudi Shanghai Jiao Tong University China ETH Zürich Switzerland University of Würzburg Germany Department of Tao Technology Alibaba Group China Kuaishou Technology China Interactive Entertainment Group of Netease Inc Guangzhou China Transsion China Vrobotit Lab Beijing University of Posts and Telecommunications China Hefei University of Technology China Department of Informatics Systems and Communication University of Milano - Bicocca Italy Xiaomi Inc. China China Ji Liang University China FreeTech China Advanced Research Center KKCompany Taiwan ByteDance China MGTV China Fuzhou University China Shopee Information Technology Co. Ltd. China S-Lab Nanyang Technological University Singapore Hunan University China Hangzhou Dianzi University China INSA Rennes CNRS IETR - UMR 6164 Rennes France National Higher School of Telecommunications and ICT Oran Algeria BUAA China Department of Electrical and Computer Engineering Faculty of Engineering Kharazmi University Tehran Iran High Performance Computing Laboratory School of Computer Science Institute for Research in Fundamental Sciences Tehran Iran Cyberspace Research Institute Shahid Beheshti University Tehran Iran

This paper reports on the NTIRE 2023 Quality Assessment of Video Enhancement Challenge, which will be held in conjunction with the New Trends in Image Restoration and Enhancement Workshop (NTIRE) at CVPR 2023. This challenge is to address a major challenge in the field of video processing, namely, video quality assessment (VQA) for enhanced videos. The challenge uses the VQA Dataset for Perceptual Video Enhancement (VDPVE), which has a total of 1211 enhanced videos, including 600 videos with color, brightness, and contrast enhancements, 310 videos with deblurring, and 301 deshaked videos. The challenge has a total of 167 registered participants. 61 participating teams submitted their prediction results during the development phase, with a total of 3168 submissions. A total of 176 submissions were submitted by 37 participating teams during the final testing phase. Finally, 19 participating teams submitted their models and fact sheets, and detailed the methods they used. Some methods have achieved better results than baseline methods, and the winning methods have demonstrated superior prediction performance. Copyright © 2023, The Authors. All rights reserved.

关键词： Image enhancement

来源：评论

学校读者我要写书评

暂无评论

Recent advances of transition radiation: fundamentals and applications

arXiv

引用

arXiv 2022年

作者： Chen, Ruoxi Gong, Zheng Chen, Jialin Zhang, Xinyan Zhu, Xingjian Chen, Hongsheng Lin, Xiao Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center College of Information Science & Electronic Engineering Zhejiang University Hangzhou310027 China International Joint Innovation Center The Electromagnetics Academy Zhejiang University Zhejiang University Haining314400 China Department of Electrical and Computer Engineering Technion-Israel Institute of Technology Haifa32000 Israel School of Physics Zhejiang University Hangzhou310027 China Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University Zhejiang University Jinhua321099 China Shaoxing Institute of Zhejiang University Zhejiang University Shaoxing312000 China

Transition radiation is a fundamental process of light emission and occurs whenever a charged particle moves across an inhomogeneous region. One feature of transition radiation is that it can create light emission at arbitrary frequency under any particle velocity. Therefore, transition radiation is of significant importance to both fundamental science and practical applications. In this paper, we provide a brief historical review of transition radiation and its recent development. Moreover, we pay special attention to four typical applications of transition radiation, namely the detection of high-energy particles, coherent radiation sources, beam diagnosis, and excitation of surface waves. Finally, we give an outlook for the research tendency of transition radiation, especially its flexible manipulation by exploiting artificially-engineered materials and nanostructures, such as gain materials, metamaterials, spatial-temporal materials, meta-boundaries, and layered structures with a periodic or non-periodic stacking. © 2022, CC BY.

关键词： Light emission

来源：评论

学校读者我要写书评

暂无评论

Information theoretic feature transformation learning for brain interfaces

arXiv

引用

arXiv 2019年

作者： Özdenizci, Ozan Erdoǧmuş, Deniz Cognitive Systems Laboratory Department of Electrical and Computer Engineering Northeastern University BostonMA United States

Objective: A variety of pattern analysis techniques for model training in brain interfaces exploit neural feature dimensionality reduction based on feature ranking and selection heuristics. In the light of broad evidence demonstrating the potential sub-optimality of ranking based feature selection by any criterion, we propose to extend this focus with an information theoretic learning driven feature transformation concept. Methods: We present a maximum mutual information linear transformation (MMI-LinT), and a nonlinear transformation (MMI-NonLinT) framework derived by a general definition of the feature transformation learning problem. Empirical assessments are performed based on electroencephalographic (EEG) data recorded during a four class motor imagery brain-computer interface (BCI) task. Exploiting state-of-the-art methods for initial feature vector construction, we compare the proposed approaches with conventional feature selection based dimensionality reduction techniques which are widely used in brain interfaces. Furthermore, for the multi-class problem, we present and exploit a hierarchical graphical model based BCI decoding system. Results: Both binary and multi-class decoding analyses demonstrate significantly better performances with the proposed methods. Conclusion: Information theoretic feature transformations are capable of tackling potential confounders of conventional approaches in various settings. Significance: We argue that this concept provides significant insights to extend the focus on feature selection heuristics to a broader definition of feature transformation learning in brain interfaces. Copyright © 2019, The Authors. All rights reserved.

关键词： Decoding

来源：评论

学校读者我要写书评

暂无评论

Black-box coupled-mode theory: An Ab initio framework to model electromagnetic interactions of open, lossy, and dispersive resonators

arXiv

引用

arXiv 2020年

作者： Tali, Seied Ali Safiabadi Yuan, Luqi Zhou, Wei Department of Electrical and Computer Engineering Virginia Tech BlacksburgVA24061 United States State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China

Temporal coupled-mode theory (TCMT) provides a simple yet powerful platform to model and analyze electromagnetic resonator systems. Nevertheless, restrictive assumptions and lack of rigorous connection to Maxwell’s equations limit the TCMT formulation’s generality and robustness. Herein, we present the Black-box Coupled-Mode Theory (BBCMT), a general ab initio CMT framework developed from Maxwell’s equations and quasinormal mode (QNM) theory to model the electromagnetic interactions of dispersive, lossy, and open resonators. BBCMT development is enabled by employing Poynting’s and conjugated reciprocity theorems to rigorously normalize QNMs and calculate their expansion coefficients. Our novel QNM analysis approach allows the definition of a resonator Hamiltonian matrix to characterize the modes’ electromagnetic interactions, energy storage, and absorption. Uniquely, the BBCMT framework can capture a resonator’s non-resonant scattering and absorption by treating the resonator scattered fields as a perturbation to those of a background structure, which can be flexibly chosen considering the desired accuracy-simplicity trade-off. BBCMT modeling complexity can be further adjusted by treating user-defined subcomponents of a resonator system as black-boxes described only by their input-output transfer characteristics. Beyond the BBCMT formulation, we present two lemmas to reverse-engineer the modeling parameters from calculated or measured far-field spectra. Moreover, we introduce the signal flow graphs from control theory to illustrate, interpret, and solve the BBCMT equations. To evince BBCMT’s validity and generality, we compare the BBCMT and TCMT predictions for two plasmonic nanoresonator systems to finite-difference time-domain simulations and find BBCMT results to be a much better match. BBCMT reduces to TCMT or cavity perturbation theory under certain constraints and approximations. Copyright © 2020, The Authors. All rights reserved.

关键词： Resonators

来源：评论

学校读者我要写书评

暂无评论

Prediction of fitness in bacteria with causal jump dynamic mode decomposition

Prediction of fitness in bacteria with causal jump dynamic m...

引用

American Control Conference

作者： Shara Balakrishnan Aqib Hasnain Nibodh Boddupalli Dennis M. Joshy Robert G. Egbert Enoch Yeung Department of Electrical and Computer Engineering University of California Santa Barbara Department of Mechanical Engineering University of California Santa Barbara Environmental and Biological Sciences Directorate Pacific Northwest National Laboratory Richland WA Mechanical Engineering Center for Control Dynamical Systems and Computation and Biomolecular Science and Engineering University of California Santa Barbara

ISBN: (数字)9781538682661

ISBN: (纸本)9781538682678

In this paper, we consider the problem of learning a predictive model for population cell growth dynamics as a function of the media conditions. We first introduce a generic data-driven framework for training operator-theoretic models to predict cell growth rate. We then introduce the experimental design and data generated in this study, namely growth curves of Pseudomonas putida as a function of casein and glucose concentrations. We use a data driven approach for model identification, specifically the nonlinear autoregressive (NAR) model to represent the dynamics. We show theoretically that Hankel DMD can be used to obtain a solution of the NAR model. We show that it identifies a constrained NAR model and to obtain a more general solution, we define a causal state space system using 1-step, 2-step,..., τ-step predictors of the NAR model and identify a Koopman operator for this model using extended dynamic mode decomposition. The hybrid scheme we call causal-jump dynamic mode decomposition, which we illustrate on a growth profile or fitness prediction challenge as a function of different input growth conditions. We show that our model is able to recapitulate training growth curve data with 96.6% accuracy and predict test growth curve data with 91% accuracy.

关键词： health Growth curves SOLUTIONS(GENERAL) model identification bacteria data driven Pseudomonas putida

来源：评论

学校读者我要写书评

暂无评论

B1+ Homogenization in 7T MRI using mode-shaping with high permittivity materials

arXiv

引用

arXiv 2019年

作者： Hwang, Yunchan Noh, Hansol Park, Minkyu Lee, Jongho Park, Namkyoo Photonic Systems Laboratory Department of Electrical and Computer Engineering Seoul National University Seoul Korea Republic of Laboratory for Imaging Science and Technology Department of Electrical and Computer Engineering Seoul National University Seoul Korea Republic of

—Ultra high field (UHF) brain MRI has proved its value by providing enhanced SNR, contrast, and higher resolution derived from the higher magnetic field (B0). Nonetheless, with the increased B0 of UHF MRI, the transmit RF magnetic field (B1+) inhomogeneity also became one of the critical issues requiring attention. As the effective wavelength of RF becomes comparable or smaller than the dimension of the brain at B0 larger than 7 Tesla, the increased B1+ inhomogeneity of UHF MRI results in poor SNR and uneven contrast. While parallel transmission techniques (PTx) and high permittivity material (HPM) structures for the mitigation of B1+ inhomogeneity have been suggested, the associated complexity in PTx and restricted volume of homogenization with HPM approach still remain as challenges. In this work, we address the B1+ inhomogeneity in the notion of mode-shaping. Treating a brain phantom as a dielectric potential-well resonator, we apply a phantom-conformal HPM potential-well in combination with a low-index potential barrier (air), to achieve the homogeneity of B1+ in the region of interest (ROI). Based on the electromagnetic simulations using a realistic brain model at 7T, we show that the proposed HPM structure reduces both the average deviation of B1+ in axial slices by 54% and peak SAR by 42%, respectively. Copyright © 2019, The Authors. All rights reserved.

关键词： Electromagnetic simulation

来源：评论

学校读者我要写书评

暂无评论

Defect engineering of silicon with ion pulses from laser acceleration

arXiv

引用

arXiv 2022年

作者： Redjem, Walid Amsellem, Ariel J. Allen, Frances I. Benndorf, Gabriele Bin, Jianhui Bulanov, Stepan Esarey, Eric Feldman, Leonard C. Fernandez, Javier Ferrer Lopez, Javier Garcia Geulig, Laura Geddes, Cameron R. Hijazi, Hussein Ji, Qing Ivanov, Vsevolod Kante, Boubacar Gonsalves, Anthony Meijer, Jan Nakamura, Kei Persaud, Arun Pong, Ian Obst-Huebl, Lieselotte Seidl, Peter A. Simoni, Jacopo Schroeder, Carl Steinke, Sven Tan, Liang Z. Wunderlich, Ralf Wynne, Brian Schenkel, Thomas Department of Electrical Engineering and Computer Science University of California BerkeleyCA94720 United States Accelerator Technology and Applied Physics Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Materials Science and Engineering University of California BerkeleyCA94720 United States California Institute for Quantitative Biosciences University of California BerkeleyCA94720 United States Felix-Bloch Institute for Solid State Physics Department: Applied Quantum Systems Linnéstr. 5 LeipzigD-04103 Germany Rutgers University Department of Physics & Astronomy 136 Frelinghuysen Rd PiscatawayNJ08854 United States University of Seville Seville Facultad de Física Centro Nacional de Aceleradores Sevilla41092 Spain Molecular Foundry Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Nuclear Engineering University of California BerkeleyCA94720 United States

Defect engineering is foundational to classical electronic device development and for emerging quantum devices. Here, we report on defect engineering of silicon single crystals with ion pulses from a laser accelerator with ion flux levels up to 1022 ions/cm2/s. Low energy ions from plasma expansion of the laser-foil target are implanted near the surface and then diffuse into silicon samples that were locally pre-heated by high energy ions. We observe low energy ion fluences of ~1016 cm-2, about four orders of magnitude higher than the fluence of high energy (MeV) ions. In the areas of highest energy deposition, silicon crystals exfoliate from single ion pulses. Color centers, predominantly W and G-centers, form directly in response to ion pulses without a subsequent annealing step. We find that the linewidths of G-centers increase in areas with high ion flux much more than the linewidth of W-centers, consistent with density functional theory calculations of their electronic structure. Laser ion acceleration generates aligned pulses of high and low energy ions that expand the parameter range for defect engineering and doping of semiconductors with tunable balances of ion flux, damage rates and local heating. © 2022, CC BY.

关键词： Density functional theory

来源：评论

学校读者我要写书评

暂无评论

Passive Quadrupedal Gait Synchronization for Extra Robotic Legs Using a Dynamically Coupled Double Rimless Wheel Model

arXiv

引用

arXiv 2020年

作者： Gonzalez, Daniel J. Harry Asada, H. Robotics Research Center Department of Electrical Engineering and Computer Science United States Military Academy West PointNY10996 United States d’Arbeloff Laboratory for Information Systems and Technology Department of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States

The Extra Robotic Legs (XRL) system is a robotic augmentation worn by a human operator consisting of two articulated robot legs that walk with the operator and help bear a heavy backpack payload. It is desirable for the Human-XRL quadruped system to walk with the rear legs lead the front by 25% of the gait period, minimizing the energy lost from foot impacts while maximizing balance stability. Unlike quadrupedal robots, the XRL cannot command the human’s limbs to coordinate quadrupedal locomotion. Using a pair of Rimless Wheel models, it is shown that the systems coupled with a spring and damper converge to the desired 25% phase difference. A Poincaré return map was generated using numerical simulation to examine the convergence properties to different coupler design parameters, and initial conditions. The Dynamically Coupled Double Rimless Wheel system was physically realized with a spring and dashpot chosen from the theoretical results, and initial experiments indicate that the desired synchronization properties may be achieved within several steps using this set of passive components alone. Copyright © 2020, The Authors. All rights reserved.

关键词： Exoskeleton (Robotics)

来源：评论

学校读者我要写书评

暂无评论

Convex relaxation of combined heat and power dispatch

arXiv

引用

arXiv 2020年

作者： Jiang, Yibao Wan, Can Botterud, Audun Song, Yonghua Shahidehpour, Mohammad College of Electrical Engineering Zhejiang University Hangzhou310027 China Laboratory for Information and Decision Systems Massachusetts Institute of Technology CambridgeMA02139 United States State Key Laboratory of Internet of Things for Smart City University of Macau Taipa China Electrical and Computer Engineering Department Illinois Institute of Technology ChicagoIL60616 United States

Combined heat and power dispatch promotes interactions and synergies between electric power systems and district heating systems. However, nonlinear and nonconvex heating flow imposes significant challenges on finding qualified solutions efficiently. Most existing methods rely on constant flow assumptions to derive a linear heating flow model, sacrificing optimality for computational simplicity. This paper proposes a novel convex combined heat and power dispatch model based on model simplification and constraint relaxation, which improves solution quality and avoids assumptions on operating regimes of district heating systems. To alleviate mathematical complexity introduced by the commonly used node method, a simplified thermal dynamic model is proposed to capture temperature changes in networked pipelines. Conic and polyhedral relaxations are then applied to convexify the original problems with bilinear and quadratic equality constraints. Furthermore, an adaptive solution algorithm is proposed to successively reduce relaxation gaps based on dynamic bivariate partitioning, improving solution optimality with desirable computational efficiency. The proposed method is verified on a 33-bus electric power system integrated with a 30-node district heating system and compared to nonlinear programming solvers and constant-flow-based solutions. Copyright © 2020, The Authors. All rights reserved.

关键词： Integer programming

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：