检索结果-内蒙古大学图书馆

Localization transition induced by programmable disorder

Physical Review B 2022年第13期105卷 134201-134201页

作者： Jaime L. C. da C. Filho Zoe Gonzalez Izquierdo Andreia Saguia Tameem Albash Itay Hen Marcelo S. Sarandy Instituto Federal do Pará - Campus Castanhal BR 316 Km 61 Saudade II 68740-970 Castanhal PA Brazil QuAIL NASA Ames Research Center Moffett Field California 94035 USA USRA Research Institute for Advanced Computer Science Mountain View California 94043 USA Instituto de Física Universidade Federal Fluminense Av. Gal. Milton Tavares de Souza s/n Gragoatá 24210-346 Niterói Rio de Janeiro Brazil Department of Electrical and Computer Engineering University of New Mexico Albuquerque New Mexico 87131 USA Department of Physics and Astronomy and Center for Quantum Information and Control CQuIC University of New Mexico Albuquerque New Mexico 87131 USA Department of Physics and Astronomy and Center for Quantum Information Science & Technology University of Southern California Los Angeles California 90089 USA Information Sciences Institute University of Southern California Marina del Rey California 90292 USA

We investigate the occurrence of many-body localization (MBL) on a spin-1/2 transverse-field Ising model defined on a Chimera connectivity graph with random exchange interactions and longitudinal fields. We observe a transition from an ergodic phase to a nonthermal phase for individual energy eigenstates induced by a critical disorder strength for the Ising parameters. Our result follows from the analysis of both the mean half-system block entanglement and the energy-level statistics. We identify the critical point associated with this transition using the maximum variance of the block entanglement over the disorder ensemble as a function of the disorder strength. The calculated energy density phase diagram shows the existence of a mobility edge in the energy spectrum. In terms of the energy-level statistics, the system changes from the Gaussian orthogonal ensemble for weak disorder to a Poisson distribution limit for strong randomness, which implies localization behavior. We then realize the time-independent disordered Ising Hamiltonian experimentally using a reverse annealing quench-pause-quench protocol on a D-wave 2000Q programmable quantum annealer. We characterize the transition from the thermal to the localized phase through magnetization measurements at the end of the annealing dynamics, and the results are compatible with our theoretical prediction for the critical point. However, the same behavior can be reproduced using a classical spin-vector Monte Carlo simulation, which suggests that genuine quantum signatures of the phase transition remain out of reach using this experimental platform and protocol.

关键词： Adiabatic quantum optimization Many-body localization Disordered systems Quantum spin models Annealing

来源：评论

学校读者我要写书评

暂无评论

On the Promise of the Stochastic Generalized Gauss-Newton Method for Training DNNs

arXiv

引用

arXiv 2020年

作者： Gargiani, Matilde Diehl, Moritz Zanelli, Andrea Hutter, Frank Automatic Control Laboratory ETH Zurich Department of Microsystems Engineering Department of Mathematics University of Freiburg Department of Microsystems Engineering University of Freiburg Department of Computer Science University of Freiburg Bosch Center for Artificial Intelligence

Following early work on Hessian-free methods for deep learning, we study a stochastic generalized Gauss-Newton method (SGN) for training deep neural networks. SGN is a second-order optimization method, with efficient iterations, that we demonstrate to often require substantially fewer iterations than standard SGD to converge. As the name suggests, SGN uses a Gauss-Newton approximation for the Hessian matrix, and, in order to efficiently compute an approximate search direction, relies on the conjugate gradient method combined with forward and reverse automatic differentiation. Despite the success of SGD and its first-order variants in deep learning applications, and despite Hessian-free methods based on the Gauss-Newton Hessian approximation having been already theoretically proposed as practical methods for training neural networks, we believe that SGN has a lot of undiscovered and yet not fully displayed potential in big mini-batch scenarios. For this setting, we demonstrate that SGN does not only substantially improve over SGD in terms of the number of iterations, but also in terms of runtime. This is made possible by an efficient, easy-to-use and flexible implementation of SGN we propose in the Theano deep learning platform, which, unlike Tensorflow and Pytorch, supports forward automatic differentiation. This enables researchers to further study and improve this promising optimization technique and hopefully reconsider stochastic second-order methods as competitive optimization techniques for training DNNs;we also hope that the promise of SGN may lead to forward automatic differentiation being added to Tensorflow or Pytorch. Our results also show that in big mini-batch scenarios SGN is more robust than SGD with respect to its hyperparameters (we never had to tune its step-size for our benchmarks!), which eases the expensive process of hyperparameter tuning that is instead crucial for the performance of first-order methods. Copyright © 2020, The Authors. All righ

关键词： Stochastic systems

来源：评论

学校读者我要写书评

暂无评论

Semi-Explicit Solution of Some Discrete-Time Mean-Field-Type control with Higher-Order Costs

arXiv

引用

arXiv 2025年

作者： Barreiro-Gomez, Julian Duncan, Tyrone E. Pasik-Duncan, Bozenna Tembine, Hamidou KU Center for Autonomous Robotic Systems Department of Computer and Information Engineering Khalifa University Abu Dhabi127788 United Arab Emirates Department of Electrical Engineering and Computer Science School of Engineering Université du Québec à Trois-Rivières UQTR QC Canada Timadie Guinaga Grabal AI Mali TF WETE MFTG LnG Lab CI4SI Canada Department of Mathematics University of Kansas. Nichols Hall 2335 Irving Hill Rd LawrenceKS66045 United States

Traditional solvable optimal control theory predominantly focuses on quadratic costs due to their analytical tractability, yet they often fail to capture critical non-linearities inherent in real-world systems including water, energy, agriculture, and financial networks. Here, we present a unified framework for solving discrete-time optimal control with higher-order state and control costs of power-law form. By building convex-completion techniques, we derive semi-explicit expressions for control laws, cost-to-go functions, and recursive coefficient dynamics across deterministic and stochastic system settings. Key contributions include variance-aware solutions under additive and multiplicative noise, extensions to mean-field-type-dependent dynamics, and conditions that ensure the positivity of recursive coefficients. In particular, we establish that higher-order costs induce less aggressive control policies compared to quadratic formulations, a finding that is validated through numerical analyses. © 2025, CC BY-NC-ND.

关键词： Discrete time control systems

来源：评论

学校读者我要写书评

暂无评论

Email notifier using named entity extraction

引用

AIP Conference Proceedings 2023年第1期2523卷

作者： K. Anand M. Vijay Anand R. Saravanan 1Department Information Technology Center for Artificial Intelligence and Research Chennai Institute of Technology Chennai Tamil Nadu India 2Department of Computer Science and Engineering Saveetha Engineering College (Autonomous) Chennai Tamil Nadu India 3Department Information Technology Center for Artificial Intelligence and Research Chennai Institute of Technology Chennai Tamil Nadu India

Email plays an essential role in communication and its flexibility, simplicity, diversified types, and low cost of information in the modern world. Therefore handling out a large volume of emails takes are mark able amount of human power and time. To quickly extract the named entities from an email requires an automated solution. So we proposed a tool to extract named entities from emails. This solution incorporates the latest technologies like NLP (Natural Language Processing) and IR (Information Retrieval). This would perform named entities extraction of email automatically organizes and notifies the user. The proposed mechanism can be used in many organizations. Named Entity Recognition (NER) will be a vital language processing tool for information retrieval from texts like newspapers, blogs, and emails. NER performs the classification of words and sensing the expression of text from unstructured data. Spa Cy may be a free, open-source python library for advanced language Processing. It is well known for production use and helps build the system that performs understanding of a text. It helps in information extraction, understanding the plans, and preprocesses the text for deep learning.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Cubic singularities in binary linear electromechanical oscillators

arXiv

引用

arXiv 2023年

作者： Zhou, Xin Jing, Hui Ren, Xingjing Zhang, Jianqi Huang, Ran Li, Zhipeng Sun, Xiaopeng Wu, Xuezhong Qiu, Cheng-Wei Nori, Franco Xiao, Dingbang College of Intelligence Science and Technology NUDT Changsha410073 China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control Ministry of Education Department of Physics Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Changsha410081 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Innovation Academy of Precision Measurement Science and Technology Chinese Academy of Sciences Wuhan430071 China Theoretical Quantum Physics Laboratory Cluster for Pioneering Research RIKEN Wako-shi Saitama351-0198 Japan Department of Electrical and Computer Engineering National University of Singapore Singapore117576 Singapore

Singularities arise in diverse disciplines and play a key role in both exploring fundamental laws of physics and making highly-sensitive sensors [1–14]. Higher-order (≥ 3) singularities, with further improved performance [15–19], however, usually require exquisite tuning of multiple (≥ 3) coupled degrees of freedom [15–17] or nonlinear control [18, 19], thus severely limiting their applications in practice. Here we propose theoretically and confirm using mechanics experiments that, cubic singularities can be realized in a coupled binary system without any nonlinearity, only by observing the phase tomography of the driven response. By steering the cubic phase-tomographic singularities in an electrostatically-tunable micromechanical system, enhanced cubic-root response to frequency perturbation and voltage-controlled nonreciprocity are demonstrated. Our work opens up a new phase-tomographic method for interacted-system research, and sheds new light on building and engineering advanced singular devices with simple and well-controllable elements, with a wide range of applications including precision metrology, portable nonreciprocal devices, and on-chip mechanical computing. © 2023, CC BY-SA.

关键词： Degrees of freedom (mechanics)

来源：评论

学校读者我要写书评

暂无评论

Epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China: a retrospective cohort study (vol 15, pg 613, 2020)

引用

LANCET INFECTIOUS DISEASES 2020年第7期20卷 148-148页

作者： Bi, Qifang Wu, Yongsheng Mei, Shujiang Ye, Chenfei Zou, Xuan Zhang, Zhen Liu, Xiaojian Wei, Lan Truelove, Shaun A. Zhang, Tong Gao, Wei Cheng, Cong Tang, Xiujuan Wu, Xiaoliang Wu, Yu Sun, Binbin Huang, Suli Sun, Yu Zhang, Juncen Ma, Ting Lessler, Justin Feng, Tiejian Department of Epidemiology Johns Hopkins Bloomberg School of Public Health Baltimore MD USA. Department of Public Health Information Shenzhen China. Department of Communicable Diseases Control and Prevention Shenzhen China. School of Electronic and Information Engineering Harbin Institute of Technology at Shenzhen Shenzhen China Artificial Intelligence Research Center Peng Cheng Laboratory Shenzhen China. Shenzhen Center for Disease Control and Prevention Shenzhen China. Department of International Health Johns Hopkins Bloomberg School of Public Health Baltimore MD USA. Artificial Intelligence Research Center Peng Cheng Laboratory Shenzhen China. Department of School Health Shenzhen China. School of Computer Science Harbin Institute of Technology at Shenzhen Shenzhen China Artificial Intelligence Research Center Peng Cheng Laboratory Shenzhen China. Department of Environment and Health Shenzhen China. School of Electronic and Information Engineering Harbin Institute of Technology at Shenzhen Shenzhen China Artificial Intelligence Research Center Peng Cheng Laboratory Shenzhen China. Electronic address: tma@***. Department of Epidemiology Johns Hopkins Bloomberg School of Public Health Baltimore MD USA. Electronic address: justin@jhu.edu. Shenzhen Center for Disease Control and Prevention Shenzhen China. Electronic address: fengtiej@***.

Rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China, prompted heightened surveillance in Shenzhen, China. The resulting data provide a rare opportunity to measure key metrics of disease course, transmission, and the impact of control measures.;From Jan 14 to Feb 12, 2020, the Shenzhen center for Disease control and Prevention identified 391 SARS-CoV-2 cases and 1286 close contacts. We compared cases identified through symptomatic surveillance and contact tracing, and estimated the time from symptom onset to confirmation, isolation, and admission to hospital. We estimated metrics of disease transmission and analysed factors influencing transmission risk.;Cases were older than the general population (mean age 45 years) and balanced between males (n=187) and females (n=204). 356 (91%) of 391 cases had mild or moderate clinical severity at initial assessment. As of Feb 22, 2020, three cases had died and 225 had recovered (median time to recovery 21 days; 95% CI 20-22). Cases were isolated on average 4·6 days (95% CI 4·1-5·0) after developing symptoms; contact tracing reduced this by 1·9 days (95% CI 1·1-2·7). Household contacts and those travelling with a case were at higher risk of infection (odds ratio 6·27 [95% CI 1·49-26·33] for household contacts and 7·06 [1·43-34·91] for those travelling with a case) than other close contacts. The household secondary attack rate was 11·2% (95% CI 9·1-13·8), and children were as likely to be infected as adults (infection rate 7·4% in children <10 years vs population average of 6·6%). The observed reproductive number (R) was 0·4 (95% CI 0·3-0·5), with a mean serial interval of 6·3 days (95% CI 5·2-7·6).;Our data on cases as well as their infected and uninfected close contacts provide key insights into the epidemiology of SARS-CoV-2. This analysis shows that isolation and contact tracing reduce the time during which cases are infectious in the community, thereby reducing the R. The overall imp

关键词：

来源：评论

学校读者我要写书评

暂无评论

Automated osteoporosis classification and T-score prediction using hip radiographs via deep learning algorithm

引用

Therapeutic Advances in Musculoskeletal Disease 2024年 16卷

作者： Chen, Yu-Pin Chan, Wing P. Zhang, Han-Wei Tsai, Zhi-Ren Peng, Hsiao-Ching Huang, Shu-Wei Jang, Yeu-Chai Kuo, Yi-Jie Department of Orthopedics Wan Fang Hospital Taipei Medical University Taipei City Taiwan Department of Orthopedics School of Medicine College of Medicine Taipei Medical University Taipei City Taiwan Department of Radiology Wan Fang Hospital Taipei Medical University Taipei City Taiwan Department of Radiology School of Medicine College of Medicine Taipei Medical University Taipei City Taiwan Biomedica Corporation New Taipei City Taiwan Program for Aging China Medical University Taichung City Taiwan Institute of Population Health Sciences National Health Research Institutes Miaoli County Taiwan Department of Electrical and Computer Engineering Institute of Electrical Control Engineering National Yang Ming Chiao Tung University Hsinchu County Hsinchu City Taiwan Department of Computer Science and Information Engineering Asia University Taichung City Taiwan Department of Medical Research China Medical University Hospital China Medical University Taichung City Taiwan Center for Precision Medicine Research Asia University Taichung City Taiwan Department of Applied Science National Taitung University Taitung County Taitung City Taiwan Department of Orthopedics Wan Fang Hospital Taipei Medical University No. 111 Sec. 3 Xinglong Road Wenshan Taipei 11696 Taiwan Department of Orthopedics School of Medicine College of Medicine Taipei Medical University Taipei Taiwan

Background: Despite being the gold standard for diagnosing osteoporosis, dual-energy X-ray absorptiometry (DXA) is an underutilized screening tool for osteoporosis. Objectives: This study proposed and validated a controllable feature layer of a convolutional neural network (CNN) model with a preprocessing image algorithm to classify osteoporosis and predict T-score on the proximal hip region via simple hip radiographs. Design: This was a single-center, retrospective study. Methods: An image dataset of 3460 unilateral hip images from 1730 patients (age ⩾50 years) was retrospectively collected with matched DXA assessment for T-score for the targeted proximal hip regions to train (2473 unilateral hip images from 1430 patients) and test (497 unilateral hip images from 300 patients) the proposed CNN model. All images were processed with a fully automated CNN model, X1AI-Osteo. Results: The proposed screening tool illustrated a better performance (sensitivity: 97.2%;specificity: 95.6%;positive predictive value: 95.7%;negative predictive value: 97.1%;area under the curve: 0.96) than the open-sourced CNN models in predicting osteoporosis. Moreover, when combining variables, including age, body mass index, and sex as features in the training metric, there was high consistency in the T-score on the targeted hip regions between the proposed CNN model and the DXA (r = 0.996, p < 0.001). Conclusion: The proposed CNN model may identify osteoporosis and predict T-scores on the targeted hip regions from simple hip radiographs with high accuracy, highlighting the future application for population-based opportunistic osteoporosis screening with low cost and high adaptability for a broader population at risk. Trial registration: TMU-JIRB N201909036. © The Author(s), 2024.

关键词： deep learning neural network osteoporosis radiographs T-score

来源：评论

学校读者我要写书评

暂无评论

Brain structure can mediate/moderate the relationship of behavior to brain function and transcriptome: a preliminary study

arXiv

引用

arXiv 2022年

作者： Bari, Sumra Vike, Nicole L. Stetsiv, Khrystyna Blood, Anne J. Nauman, Eric A. Talavage, Thomas M. Slobounov, Semyon Breiter, Hans C. Department of Computer Science University of Cincinnati CincinnatiOH United States Warren Wright Adolescent Center Department of Psychiatry and Behavioral Sciences Feinberg School of Medicine Northwestern University ChicagoIL United States Mood and Motor Control Laboratory Departments of Neurology and Psychiatry Massachusetts General Hospital Harvard Medical School BostonMA02129 United States Laboratory of Neuroimaging and Genetics Department of Psychiatry Massachusetts General Hospital Harvard Medical School BostonMA02129 United States Martinos Center for Biomedical Imaging Department of Radiology Massachusetts General Hospital Harvard Medical School BostonMA02129 United States Department of Biomedical Engineering University of Cincinnati CincinnatiOH United States Department of Kinesiology Pennsylvania State University University ParkPA United States The Pennsylvania State University 268P Recreation Building University ParkPA16802 United States Department of Computer Science College of Engineering and Applied Science University of Cincinnati 2901 Woodside Drive CincinnatiOH45219 United States

Abnormalities in motor-control behavior, which have been associated with concussion and head acceleration events (HAE), can be quantified using virtual reality (VR) technologies. Motor-control behavior has been consistently mapped to the brain’s somatomotor network (SM) using both structural (sMRI) and functional MRI (fMRI). However, no studies have integrated HAE, motor-control behavior, sMRI and fMRI measures. Here, brain networks important for motor-control were hypothesized to show changes in tractography-based diffusion weighted imaging [difference in fractional anisotropy (∆FA)] and resting-state fMRI (rs-fMRI) measures in collegiate American football players across the season, and that these measures would relate to VR-based motor-control. We further tested if nine inflammation-related miRNAs were associated with behavior-structure-function variables. Using permutation-based mediation/moderation methods, we found that across-season ∆FA from the SM structural connectome (SM-∆FA) mediated the relationship between across-season VR-based Sensory-motor Reactivity (∆SR) and rs-fMRI SM fingerprint similarity (psobelperm = 0.007 and Teff = 47%). The interaction between ∆SR and SM-∆FA also predicted (pFPerm= 0.036, PB₃perm = 0.058) across-season levels of ∆miRNA-30d through permutation-based moderation analysis. These results suggest (1) that motor-control is in a feedback relationship with brain structure and function, (2) behavior-structure-function can be connected to HAE, and (3) behavior-structure might predict molecular biology measures. © 2022, CC BY.

关键词： Molecular biology

来源：评论

学校读者我要写书评

暂无评论

Impasse Surface of Differential-Algebraic Power System Models: An Interpretation Based on Admittance Matrices

arXiv

引用

arXiv 2020年

作者： Song, Yue Hill, David J. Liu, Tao Zhang, Xinran The State Key Laboratory of Intelligent Autonomous Systems and Frontiers Science Center for Intelligent Autonomous Systems Tongji University Shanghai China The Department of Electrical and Electronic Engineering The University of Hong Kong Hong Kong The Department of Electrical and Computer Systems Engineering Monash University Melbourne Australia The School of Automation Science and Electrical Engineering Beihang University Beijing China

The impasse surface is an important concept in the differential-algebraic equation (DAE) model of power systems, which is associated with short-term voltage collapse. This paper establishes a necessary condition for a system trajectory hitting the impasse surface. The condition is in terms of admittance matrices regarding the power network, generators and loads, which specifies the pattern of interaction between those system components that can induce voltage collapse. It applies to generic DAE models featuring high-order synchronous generators, static loads, induction motor loads and lossy power networks. We also identify a class of static load parameters that prevent power systems from hitting the impasse surface;this proves a conjecture made by Hiskens that has been unsolved for decades. Moreover, the obtained results lead to an early indicator of voltage collapse and a novel viewpoint that inductive compensation to the power network has a positive effect on preventing short-term voltage collapse, which are verified via numerical simulations. Copyright © 2020, The Authors. All rights reserved.

关键词： Differential equations

来源：评论

学校读者我要写书评

暂无评论

Applications of Game Theory in Vehicular Networks: A Survey

arXiv

引用

arXiv 2021年

作者： Sun, Zemin Liu, Yanheng Wang, Jian Li, Guofa Anil, Carie Li, Keqiang Guo, Xinyu Sun, Geng Tian, Daxin Cao, Dongpu College of Computer Science and Technology Jilin University Changchun130012 China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun130012 China Institute of Human Factors and Ergonomics College of Mechatronics and Control Engineering Shenzhen University Guangdong Shenzhen518060 China School of Computer Science and Engineering VIT-AP Andhra Pradesh Amaravati522237 India College of Engineering Nanjing Agricultural University Nanjing210031 China State Key Laboratory of Automotive Safety and Energy Department of Automotive Engineering Tsinghua University Beijing100084 China Beijing Advanced Innovation Center for Big Data and Brain Computing Beijing Key Laboratory for Cooperative Vehicle Infrastructure Systems and Safety Control School of Transportation Science and Engineering Beihang University Beijing100191 China Waterloo Cognitive Autonomous Driving Lab University of Waterloo N2L 3G1 Canada

In the Internet of things (IoT) era, vehicles and other intelligent components in an intelligent transportation system (ITS) are connected, forming vehicular networks (VNs) that provide efficient and safe traffic and ubiquitous access to various applications. However, as the number of nodes in an ITS increases, it is challenging to satisfy a varied and large number of service requests with different quality of service (QoS) and security requirements in highly dynamic VNs. Intelligent nodes in VNs can compete or cooperate for limited network resources to achieve the objective for either an individual or a group. Game theory (GT), a theoretical framework designed for strategic interactions among rational decision makers sharing scarce resources, can be used to model and analyze individual or group behaviors of communicating entities in VNs. This paper primarily surveys the recent developments of GT in solving various challenges of VNs. This survey starts with an introduction to the background of VNs. A review of GT models studied in the VNs is then introduced, including the basic concepts, classifications, and applicable vehicular issues. After discussing the requirements of VNs and the motivation of using GT, a comprehensive literature review on GT applications in dealing with the challenges of current VNs is provided. Furthermore, recent contributions of GT to VNs that are integrated with diverse emerging 5G technologies are surveyed. Finally, the lessons learned are given, and several key research challenges and possible solutions of applying GT in VNs are outlined. Copyright © 2021, The Authors. All rights reserved.

关键词： Quality of service

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：