检索结果-内蒙古大学图书馆

arXiv 2023年

作者： Xue, Haoran Yang, Yihao Zhang, Baile Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore637371 Singapore Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic Engineering ZJU-Hangzhou Global Science and Technology Innovation Center Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang ZJU-UIUC Institute Zhejiang University Hangzhou310027 China Centre for Disruptive Photonic Technologies Nanyang Technological University Singapore637371 Singapore

Topological acoustics is an emerging field that lies at the intersection of condensed matter physics, mechanical structural design and acoustics engineering. It explores the design and construction of novel artificial structures, such as acoustic metamaterials and phononic crystals, to manipulate sound waves robustly, taking advantage of topological protection. Early work on topological acoustics was limited to duplicating topological phases that have been understood in condensed matter systems, but recent advances have shifted the paradigm to exploring novel topological concepts that are difficult to realize in other physical systems, such as various topological semimetal phases, and topological phases associated with Floquet engineering, fragile topology, non-Hermiticity and synthetic dimensions. These developments demonstrate the unique advantages of topological acoustic systems and their role in developing topological physics. In this Review, we survey the fundamental mechanisms, basic designs and practical realizations of topological phases in acoustic systems, and provide an overview of future directions and potential applications. Copyright © 2023, The Authors. All rights reserved.

关键词： Topology

来源：评论

学校读者我要写书评

暂无评论

4d Printed Tmp Origami Metamaterials with Programmable Mechanical Properties

SSRN

引用

SSRN 2022年

作者： Wan, Mengqi Yu, Keqin Gu, Jianping Zeng, Hao Sun, Huiyu Khatibi, Akbar A. State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing210016 China Nanjing Fiberglass Research & Design Institute Co. Ltd. Nanjing210012 China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and Engineering Nanjing Institute of Technology Nanjing211167 China School of Physical and Mathematical Sciences Nanjing Tech University Nanjing211800 China RMIT University Australia

Origami structures have received significant attention in engineering due to their unique design methods and deformation modes along the crease lines. However, the configurations of origami structures are fixed after fabrication, and their mechanical properties are tough to tune and adapt. To overcome this limitation, herein, a 4D printing method is employed to develop Tachi-Miura Polyhedron (TMP) origami metamaterials with reconfigurable shapes and programmable mechanical properties. The elastic modulus, folding/unfolding deformations, force-displacement curves and Poisson’s ratios of TMP origami metamaterials under different structure parameters and temperature are studied through theoretical models, finite element analysis (FEA) and experiments. Results reveal that the TMP origami structures can achieve negative Poisson’s ratios, and their deformation modes can switch between monostable and bistable states. Due to shape memory effects, deformation shapes and mechanical properties can be programmed by controlling temperature and tuning structural parameters. The 4D Printed origami metamaterials can provide practical solutions in various engineering applications such as self-deployable structures, energy absorption devices and flexible electronics. © 2022, The Authors. All rights reserved.

关键词： Metamaterials

来源：评论

学校读者我要写书评

暂无评论

Group Signatures with Decentralized Tracing 15th

Group Signatures with Decentralized Tracing

引用

15th International Conference on Information Security and Cryptology, Inscrypt 2019

作者： Lu, Tingting Li, Jiangtao Zhang, Lei Lam, Kwok-Yan Shanghai Key Laboratory of Trustworthy Computing Software Engineering Institute East China Normal University Shanghai China State Key Laboratory of Cryptology P.O. Box 5159 Beijing China Shanghai Institute for Advanced Communication and Data Science Shanghai China School of Computer Engineering and Science Shanghai University Shanghai China Nanyang Technological University Singapore Singapore

ISBN: (纸本)9783030429201

Group signature is a useful cryptographic primitive that allows a message to be signed by a user on behalf of a group which is managed by some trusted authority, namely the group manager. However, group signature schemes typically place a disturbingly high level of trust on the group manager, which has become a major deployment issue in cyber applications where there is no centralized trust management. In this paper, we investigate mechanisms that aim to achieve a balance between anonymity and accountability in group signatures by decentralizing the operation of tracing the signer. We propose a practical group signature scheme with decentralized tracing. When comparing with a similar result by Benjumea et al. (FC 2008), our proposal has the advantage of a shorter signature size. © 2020, Springer Nature Switzerland AG.

关键词： Managers

来源：评论

学校读者我要写书评

暂无评论

Superconductivity in pressurized trilayer La4Ni3O10-δ single crystals

arXiv

引用

arXiv 2023年

作者： Zhu, Yinghao Peng, Di Zhang, Enkang Pan, Bingying Chen, Xu Chen, Lixing Ren, Huifen Liu, Feiyang Hao, Yiqing Li, Nana Xing, Zhenfang Lan, Fujun Han, Jiyuan Wang, Junjie Jia, Donghan Wo, Hongliang Gu, Yiqing Gu, Yimeng Ji, Li Wang, Wenbin Gou, Huiyang Shen, Yao Ying, Tianping Chen, Xiaolong Yang, Wenge Cao, Huibo Zheng, Changlin Zeng, Qiaoshi Guo, Jiangang Zhao, Jun State Key Laboratory of Surface Physics Department of Physics Fudan University Shanghai200433 China Shanghai Research Center for Quantum Sciences Shanghai201315 China Shanghai201203 China College of Physics and Optoelectronic Engineering Ocean University of China Shandong Qingdao266100 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China Neutron Scattering Division Oak Ridge National Laboratory Oak RidgeTN37831 United States Center for High Pressure Science and Technology Advanced Research Shanghai201203 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China Center for High Pressure Science and Technology Advanced Research Beijing100094 China State Key Laboratory of ASIC and System School of Microelectronics Fudan University Shanghai China Institute of Nanoelectronics and Quantum Computing Fudan University Shanghai200433 China Shanghai Branch Hefei National Laboratory Shanghai201315 China

The pursuit of discovering new high-temperature superconductors that diverge from the copper-based paradigm1-3 carries profound implications for elucidating mechanisms behind superconductivity and may also enable new applications4-8. Here, our investigation reveals that application of pressure effectively suppresses the spin and charge order in trilayer nickelate La4Ni3O10-δ single crystals, leading to the emergence of superconductivity with a maximum critical temperature (Tc) of around 30 K at 69.0 GPa. The DC susceptibility measurements confirm a substantial diamagnetic response below Tc, indicating the presence of bulk superconductivity with a volume fraction exceeding 80%. In the normal state, we observe a "strange metal" behavior, characterized by a linear temperature-dependent resistance extending up to 300 K. Furthermore, the layer-dependent superconductivity observed hints at a unique interlayer coupling mechanism specific to nickelates, setting them apart from cuprates in this regard. Our findings provide crucial insights into the fundamental mechanisms underpinning superconductivity, while also introducing a new material platform to explore the intricate interplay between the spin/charge order, flat band structures, interlayer coupling, strange metal behavior and high-temperature superconductivity. © 2023, CC BY-NC-ND.

关键词： Single crystals

来源：评论

学校读者我要写书评

暂无评论

A RIS-Based Vehicle DOA Estimation Method With Integrated Sensing and Communication System

arXiv

引用

arXiv 2022年

作者： Chen, Zhimin Chen, Peng Guo, Ziyu Zhang, Yudong Wang, Xianbin The School of Electronic and Information Shanghai Dianji University Shanghai201306 China State Key Laboratory of Integrated Services Networks Xidian University Xi’an710071 China The State Key Laboratory of Millimeter Waves Southeast University Nanjing210096 China The School of Information Science and Technology Fudan University Shanghai200433 China The State Key Laboratory of Integrated Chips and Systems Fudan University Shanghai200433 China The School of Computing and Mathematical Sciences University of Leicester LeicesterLE1 7RH United Kingdom School of Computer Science and Engineering Southeast University Nanjing210096 China The Department of Electrical and Computer Engineering Western University LondonONN6A 5B9 Canada

With the development of intelligent transportation, growing attention has been received to integrated sensing and communication (ISAC) systems. In this paper, we formulate a novel passive sensing technique to obtain information on the vehicle’s direction of arrival (DOA) using reconfigurable intelligent surfaces (RIS). A novel estimation method is proposed in the scenario with a receiver using only one full-functional channel, where multiple measurements for the DOA estimation are achieved by controlling the reflection matrix (measurement matrix) in the RIS. Moreover, different from the existing estimation methods, we also consider the interference signals introduced by wireless communication in the ISAC system. Then, we propose a novel atomic norm-based method to remove the interference signals and reconstruct the sparse signal. Additionally, a novel Hankel-based multiple signal classification (MUSIC) method is formulated to obtain the DOA information after the interference removal. To reduce the interference signals more efficiently and improve the performance of the sparse reconstruction, we optimize the measurement matrix to improve the signal-to-interference-plus-noise ratio (SINR). Finally, the theoretical Cram’er-Rao lower bound (CRLB) is derived for the ISAC system on the vehicle DOA estimation. Simulation results show that the proposed method can achieve better performance in the DOA estimation, and the corresponding CRLB with different distributions of the sensing nodes are shown. The code for the proposed method is available online https://***/chenpengseu/***. Copyright © 2022, The Authors. All rights reserved.

关键词： Vehicles

来源：评论

学校读者我要写书评

暂无评论

Performing optical logic operations by a diffractive neural network

引用

Light(Science & Applications) 2020年第1期9卷 1448-1454页

作者： Chao Qian Xiao Lin Xiaobin Lin Jian Xu Yang Sun Erping Li Baile Zhang Hongsheng Chen Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical InstrumentationCollege of Information Science and Electronic EngineeringZhejiang University310027 HangzhouChina ZJU-Hangzhou Global Science and Technology Innovation Center Key Lab.of Advanced Micro/Nano Electronic Devices&Smart Systems of ZhejiangZhejiang University310027 HangzhouChina Department of Electrical Engineering California Institute of TechnologyPasadenaCAUSA ZJU-UIUC Institute Zhejiang University310027 HangzhouChina Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore

Optical logic operations lie at the heart of optical computing,and they enable many applications such as ultrahighspeed information ***,the reported optical logic gates rely heavily on the precise control of input light signals,including their phase difference,polarization,and intensity and the size of the incident *** to the complexity and difficulty in these precise controls,the two output optical logic states may suffer from an inherent instability and a low contrast ratio of ***,the miniaturization of optical logic gates becomes difficult if the extra bulky apparatus for these controls is *** such,it is desirable to get rid of these complicated controls and to achieve full logic functionality in a compact photonic *** a goal remains ***,we introduce a simple yet universal design strategy,capable of using plane waves as the incident signal,to perform optical logic operations via a diffractive neural ***,the incident plane wave is first spatially encoded by a specific logic operation at the input layer and further decoded through the hidden layers,namely,a compound Huygens’*** is,the judiciously designed metasurface scatters the encoded light into one of two small designated areas at the output layer,which provides the information of output logic ***,after training of the diffractive neural network,all seven basic types of optical logic operations can be realized by the same *** a conceptual illustration,three logic operations(NOT,OR,and AND)are experimentally demonstrated at microwave frequencies.

关键词： surface operations precise

来源：评论

学校读者我要写书评

暂无评论

SECP-AKE: Secure and efficient certificateless-password-based authenticated key exchange protocol for smart healthcare systems

引用

Journal of Systems Architecture 2025年 167卷

作者： Zhiqiang Zhao Xuexian Hu Yining Liu Jianghong Wei Yuanjun Xia Yangfan Liang State Key Laboratory of Mathematical Engineering and Advanced Computing Information Engineering University Zhengzhou 450000 Henan China School of Data Science and Artificial Intelligence Wenzhou University of Technology Wenzhou 325027 Zhejiang China School of Computer and Information Security Guilin University of Electronic Technology Guilin 541004 Guangxi China College of Information Science and Engineering the Provincial Key Laboratory of Multimodal Perceiving and Intelligent Systems the Key Laboratory of Medical Electronics and Digital Health of Zhejiang Province and the Engineering Research Center of Intelligent Human Health Situation Awareness of Zhejiang Province Jiaxing University Jiaxing 314001 Zhejiang China

Due to the importance and sensitivity of medical data, the security protection and privacy preservation of the Healthcare Internet of Things (IoT) are current research hotspots. However, existing research schemes still suffer from incomplete security properties, imperfect authentication mechanisms, and inadequate privacy preservation. Therefore, this paper presents SECP-AKE, a secure and efficient certificateless-password-based authenticated key exchange protocol for IoT-based smart healthcare, which enables batch authentication, resists physical attacks, and provides strong anonymity. Specifically, using certificateless cryptography, the SECP-AKE protocol enables batch authentication of authorized users and devices while also resolving the key escrow problem. In particular, the SECP-AKE protocol incorporates Physical Unclonable Functions (PUFs) to resist physical attacks, thus enhancing device security and ensuring reliable medical service delivery. Additionally, the design of a pseudonym update mechanism can achieve user unlinkability, thereby providing enhanced privacy preservation. The results from both formal verification using SVO logic and informal security analyses demonstrate that the SECP-AKE protocol is secure and offers more comprehensive security properties. Meanwhile, the use of a well-known automated security verification tool Scyther further evaluates the protocol’s security reliability. Ultimately, comparative experiments on communication overhead and computational overhead demonstrate that the SECP-AKE protocol is efficient and feasible compared to state-of-the-art existing works.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Wavelet analysis of stagnation point flow of non-Newtonian nanofluid

引用

Applied Mathematics and Mechanics(English Edition) 2019年第8期40卷 1211-1226页

作者： M.HAMID M.USMAN R.U.HAQ4 Z.H.KHAN Wei WANG School of Mathematical Sciences Peking UniversityBeijing 100871China BIC-ESAT College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Department of Electrical Engineering Bahria UniversityIslamabad 44000Pakistan State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource & HydropowerSichuan UniversityChengdu 610065China Key Laboratory of Advanced Reactor Engineering and Safety Ministry of Education Tsinghua UniversityBeijing 100084China

The wavelet approach is introduced to study the influence of the natural convection stagnation point flow of the Williamson fluid in the presence of thermophysical and Brownian motion effects. The thermal radiation effects are considered along a permeable stretching surface. The nonlinear problem is simulated numerically by using a novel algorithm based upon the Chebyshev wavelets. It is noticed that the velocity of the Williamson fluid increases for assisting flow cases while decreases for opposing flow cases when the unsteadiness and suction parameters increase, and the magnetic effect on the velocity increases for opposing flow cases while decreases for assisting flow cases. When the thermal radiation parameter, the Dufour number, and Williamson’s fluid parameter increase, the temperature increases for both assisting and opposing flow cases. Meanwhile, the temperature decreases when the Prandtl number increases. The concentration decreases when the Soret parameter increases, while increases when the Schmidt number increases. It is perceived that the assisting force decreases more than the opposing force. The findings endorse the credibility of the proposed algorithm, and could be extended to other nonlinear problems with complex nature.

关键词： Williamson nanofluid heat and mass transfer stagnation point flow assisting and opposing flow Chebyshev wavelet method

来源：评论

学校读者我要写书评

暂无评论

Deity: Finding Deep Rooted Bugs in JavaScript Engines

Deity: Finding Deep Rooted Bugs in JavaScript Engines

引用

International Conference on Communication Technology (ICCT)

作者： Hongyang Lin Junhu Zhu Jianshan Peng Dixia Zhu State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Henan China

Fuzzing [1] is a well-known technique which was employed to provide unexpected or random data as input to JavaScript engines in hopes of finding a security vulnerability. For effective fuzzing, the input must be both syntactically correct and uncommonly randomized for exceptions such as crashes, failing built-in code assertions, or potential memory leaks. In this work, we introduced system Deity which managed to resolve the conflict with innovative AST(Abstract Syntax Tree) [2] based tree mutation and generating methods. It leverages a high-level structural representation of intermediate process JavaScript code. Our evaluation demonstrates the effectiveness of Deity. For large-scale JavaScript engines (njs, mjs, Javascript-Core, ChakraCore, Espruino, Jerryscript) fuzzing, our results significantly show that Deity can improve code coverage and finding more deep rooted bugs (i.e., 35 new bugs, among which we discovered 21 new vulnerabilities with 3 CVEs assigned) over Superion and CodeAlchemist.

关键词： Engines Fuzzing Computer bugs Grammar Syntactics Tools

来源：评论

学校读者我要写书评

暂无评论

Optimization on the symplectic Stiefel manifold: SR decomposition-based retraction and applications

arXiv

引用

arXiv 2022年

作者： Gao, Bin Son, Nguyen Thanh Stykel, Tatjana State Key Laboratory of Scientific and Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China Institut für Mathematik Centre for Advanced Analytics and Predictive Sciences Universität Augsburg Universitätsstraße 12a Augsburg86159 Germany Thai Nguyen University of Sciences Thai Nguyen24118 Viet Nam

Numerous problems in optics, quantum physics, stability analysis, and control of dynamical systems can be brought to an optimization problem with matrix variable subjected to the symplecticity constraint. As this constraint nicely forms a so-called symplectic Stiefel manifold, Riemannian optimization is preferred, because one can borrow ideas from unconstrained optimization methods after preparing necessary geometric tools. Retraction is arguably the most important one which decides the way iterates are updated given a search direction. Two retractions have been constructed so far: one relies on the Cayley transform and the other is designed using quasi-geodesic curves. In this paper, we propose a new retraction which is based on an SR matrix decomposition. We prove that its domain contains the open unit ball which is essential in proving the global convergence of the associated gradient-based optimization algorithm. Moreover, we consider three applications—symplectic target matrix problem, symplectic eigenvalue computation, and symplectic model reduction of Hamiltonian systems—with various examples. The extensive numerical comparisons reveal the strengths of the proposed optimization *** Codes 15A23, 32C25, 65F15, 65F99, 65K05, 65P10, 90C30 © 2022, CC BY.

关键词： Dynamical systems

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：