检索结果-内蒙古大学图书馆

arXiv 2025年

作者： Jeong, Seon-Geun Duc, Pham Dang Anh Do, Quang Vinh Noh, Dae-Il Tung, Nguyen Xuan Van Chien, Trinh Pham, Quoc-Viet Hasegawa, Mikio Sekiya, Hiroo Hwang, Won-Joo Department of Information Convergence Engineering Pusan National University Pusan National University Busan46241 Korea Republic of Wireless Communications Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang University Ho Chi Minh City Viet Nam Graduate School of Engineering Chiba University Chiba263-8522 Japan Hanoi100000 Viet Nam School of Computer Science and Statistics Trinity College Dublin DublinD02PN40 Ireland Department of Electrical Engineering Tokyo University of Science Tokyo162-8601 Japan School of Computer Science and Engineering Center for Artificial Intelligence Research Pusan National University Busan46241 Korea Republic of

In wireless communication networks, it is difficult to solve many NP-hard problems owing to computational complexity and high cost. Recently, quantum annealing (QA) based on quantum physics was introduced as a key enabler for solving optimization problems quickly. However, only some studies consider quantum-based approaches in wireless communications. Therefore, we investigate the performance of a QA solution to an optimization problem in wireless networks. Specifically, we aim to maximize the sum rate by jointly optimizing clustering, subchannel assignment, and power allocation in a multi-unmanned aerial vehicle-aided wireless network. We formulate the sum rate maximization problem as a combinatorial optimization problem. Then, we divide it into two sub-problems: 1) a QA-based clustering and 2) sub-channel assignment and power allocation for a given clustering configuration. Subsequently, we obtain an optimized solution for the joint optimization problem by solving these two sub-problems. For the first sub-problem, we convert the problem into a simplified quadratic unconstrained binary optimization (QUBO) model. As for the second sub-problem, we introduce a novel QA algorithm with optimal scaling parameters to address it. Simulation results demonstrate the effectiveness of the proposed algorithm in terms of the sum rate and running time. Copyright © 2025, The Authors. All rights reserved.

关键词： Combinatorial optimization

来源：评论

学校读者我要写书评

暂无评论

Ultrastrongly-coupled and Directionally-nonreciprocal Magnon-polaritons in Magnetochiral Metamolecules

arXiv

引用

arXiv 2024年

作者： Mita, Kentaro Chiba, Takahiro Kodama, Toshiyuki Ueda, Tetsuya Nakanishi, Toshihiro Sawada, Kei Tomita, Satoshi Department of Physics Graduate School of Science Tohoku University Sendai980-8578 Japan Frontier Research Institute for Interdisciplinary Sciences Tohoku University Sendai980-8578 Japan Department of Applied Physics Graduate School of Engineering Tohoku University Sendai980-8579 Japan Institute for Excellence in Higher Education Tohoku University Sendai980-8576 Japan Department of Electrical Engineering and Electronics Kyoto Institute of Technology Kyoto606-8585 Japan Department of Electronic Science and Engineering Kyoto University Kyoto615-8510 Japan RIKEN SPring-8 Center Sayo679-5148 Japan

We experimentally demonstrate magnon-polaritons with ultrastrong coupling and directional nonreciprocity in a metamolecule lacking time-reversal and space-inversion symmetries at room temperature. These experimental results are reproduced well via numerical simulations and theoretical consideration. Ultrastrong coupling is due to a direct interaction of magnons in the magnetic meta-atom with microwave photons confined in the chiral meta-atom as a resonator. Our results reveal a crucial step in identifying deepstrongly-coupled and optically-moving magnon-polaritons for hybrid quantum systems, synthetic gauge fields, and quasi-particle "chemistry" using metamaterials. © 2024, CC BY-NC-ND.

关键词： Phonons

来源：评论

学校读者我要写书评

暂无评论

Overcoming intensity saturation in second harmonic nonlinear intersubband polaritonic metasurfaces using two-level systems 13

Overcoming intensity saturation in second harmonic nonlinear...

引用

Photonic and Phononic Properties of Engineered Nanostructures XIII 2023

作者： Krakofsky, Jonas H. Stich, Simon Cotrufo, Michele Mekawy, Ahmed Mann, Sander A. Köninger, Anna Boehm, Gerhard Alù, Andrea Belkin, Mikhail A. Walter Schottky Institute Technical University of Munich GarchingD-85748 Germany Photonics Initiative Advanced Science Research Center City University of New York New YorkNY10031 United States Physics Program Graduate Center City University of New York New YorkNY10016 United States Department of Electrical Engineering City College The City University of New York New YorkNY10031 United States

ISBN: (纸本)9781510659674

Nonlinear metasurfaces based on coupling of intersubband transitions in n-doped semiconductor heterostructures with optical modes in nanoresonators provide the largest known second-order nonlinear response in condensed matter systems in the mid-infrared spectral range. However, these giant nonlinearities are only present at relatively low pumping intensities which limits the maximum achievable frequency conversion efficiency. We experimentally investigate a new nonlinear intersubband metasurface design for second harmonic generation based on two-level nonlinear intersubband system that provides high nonlinearity combined with significantly reduced intensity saturation compared to the intersubband metasurfaces based on three-level intersubband systems demonstrated so far. © 2023 SPIE.

关键词： Harmonic generation

来源：评论

学校读者我要写书评

暂无评论

Tool for the Assessment of the Savings in the Cable Acquisition When Employing DC Transmission in Long Distance Drives

Tool for the Assessment of the Savings in the Cable Acquisit...

引用

Industrial Applications Society Annual Conference on Petroleum and Chemical Industry

作者： André M. Alzamora Caio Eduardo Silva Marco T. A. Êvo Hélder de Paula Graduate Program in Electrical Engineering Federal University of Uberlândia (UFU) Uberlândia MG Brazil Projects and Works Division (DPROB) Federal University of São João del-Rei (UFSJ) São João del-Rei MG Brazil Electrical Engineering Department (DEPEL) Federal University of São João del-Rei (UFSJ) São João del-Rei MG Brazil Faculty of Electrical Engineering (FEELT) Federal University of Uberlândia (UFU) Uberlândia MG Brazil

ISBN: (数字)9798350353402

ISBN: (纸本)9798350353419

Throughout different stages of the mining processes, alternating current (AC) motors powered by pulse width modulation (PWM) converters are employed, typically connected by extensive cable lengths. While these drives bring forth significant advantages, they also give rise to challenges associated with high-frequency problems, which, in turn, reduce the operational lifespan of the system components. Off-the-shelf solutions, involving the incorporation of passive filters, tend to adversely affect both the cost and efficiency of the system, justifying research for new alternatives. A recent proposal suggests a distinctive approach, wherein the frequency converter is divided into its rectifier and inverter units. The former is situated in its original location, while the latter is positioned close to the load. Consequently, the drive system operates with direct current (DC) for electric power transmission. This innovative topology not only eliminates the high-frequency problems but also substantially enhances efficiency while reducing costs of the transmission. Prior research has demonstrated the potential of this alternative drive topology, particularly through case studies in low- and medium-voltage systems within mining plants. In this paper, the economic and energy efficiency potentials of such DC transmission drives regarding the power transmission are examined using reference graphs that offer insights beyond conventional case studies. These graphs represent decision-making tools, allowing for a quick and accessible assessment of the economic viability of the alternative topology for a wide range of powers and drive distances. The main aspects related to the methodology, along with relevant technical discussions, are addressed.

关键词： Low voltage Costs Power transmission Medium voltage Drives Conductors Mathematical models Inverters Topology Copper

来源：评论

学校读者我要写书评

暂无评论

Gaussian Process Port-Hamiltonian Systems: Bayesian Learning with Physics Prior

Gaussian Process Port-Hamiltonian Systems: Bayesian Learning...

引用

IEEE Conference on Decision and Control

作者： Thomas Beckers Jacob Seidman Paris Perdikaris George J. Pappas Department of Electrical and Systems Engineering University of Pennsylvania Philadelphia PA USA graduate program in Applied Mathematics and Computational Science University of Pennsylvania Philadelphia PA USA Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania Philadelphia PA USA

ISBN: (数字)9781665467612

ISBN: (纸本)9781665467629

Data-driven approaches achieve remarkable results for the modeling of complex dynamics based on collected data. However, these models often neglect basic physical principles which determine the behavior of any real-world system. This omission is unfavorable in two ways: The models are not as data-efficient as they could be by incorporating physical prior knowledge, and the model itself might not be physically correct. We propose Gaussian Process Port-Hamiltonian systems (GPPHS) as a physics-informed Bayesian learning approach with uncertainty quantification. The Bayesian nature of GP-PHS uses collected data to form a distribution over all possible Hamiltonians instead of a single point estimate. Due to the underlying physics model, a GP-PHS generates passive systems with respect to designated inputs and outputs. Further, the proposed approach preserves the compositional nature of Port-Hamiltonian systems.

关键词： Uncertainty Gaussian processes Probabilistic logic Data models Bayes methods Behavioral sciences Kernel

来源：评论

学校读者我要写书评

暂无评论

Harnessing Outer Space for Improved Electrocaloric Cooling

SSRN

引用

SSRN 2024年

作者： Seo, Dong Hyun Kim, Hyung Rae Yun, Joo Ho Kim, Do Hyeon Heo, Se-Yeon Ma, Rujun Lee, Gil Ju Song, Young Min School of Electrical Engineering and Computer Science Gwangju Institute of Science and Technology Gwangju61005 Korea Republic of School of Materials Science and Engineering National Institute for Advanced Materials Smart Sensing Interdisciplinary Science Center Nankai University Tianjin300350 China Department of Electronics Engineering Pusan National University Busan46241 Korea Republic of AI Graduate School Gwangju Institute of Science and Technology Gwangju61005 Korea Republic of

Solid-state refrigeration, exploiting the electrocaloric (EC) effect, has sparked substantial interest due to its minimal energy consumption and zero-carbon emissions. However, one challenge to solid-state refrigeration technology resides in the limitation of cooling performance by the adiabatic temperature change (ΔT) inherent to caloric materials. To fully replace the traditional cooling technology, an augmentation of the innate heat dissipation capability beyond the intrinsic properties of the material is essential. In this study, we pioneer a method to transcend the native heat dissipation threshold of EC, by implementing a novel radiative heat sink/source-integrated electrocaloric (R-iEC) thermal regulation system. This system ingeniously leverages the outer cold space as a heat sink without energy. Moreover, a non-metallic thermally conductive radiative cooler (TCRC) is implemented with both a high thermal conductivity of 1.1 W/mK and exceptional spectral features (i.e., solar reflectivity ~96% and emissivity ~95% in atmospheric window region). The R-iEC system fortified with the TCRC demonstrates superior heat dissipation relative to conventional EC and radiative cooling, with an extra cooling heat flux of 87 W/m2. This improvement yields a temperature decrease of the heat source by 7.3 K relative to ambient temperature, showcasing the potential for a novel and zero-carbon emission cooling system. © 2024, The Authors. All rights reserved.

关键词： Heat flux

来源：评论

学校读者我要写书评

暂无评论

Nanometer-Scale Photodetectors for High Performance and Unique Functionality

Nanometer-Scale Photodetectors for High Performance and Uniq...

引用

International Conference on Emerging Wireless Communication Technologies and Information Security, EWCIS 2020

作者： Inokawa, Hiroshi Satoh, Hiroaki Banerjee, Amit Nagarajan, Anitharaj Manivannan, Revathi Singh, Alka Nishimura, Tomoki Isogai, Koki Research Institute of Electronics Shizuoka University Shizuoka Japan Department of Electrical and Computer Engineering National University of Singapore Singapore Singapore Graduate School of Science and Technology Shizuoka University Shizuoka Japan Graduate School of Integrated Science and Technology Shizuoka University Shizuoka Japan

ISBN: (纸本)9789813363922

As opposed to the case with MOSFETs widely used in the very-large-scale integrated circuit, miniaturization of the photodetectors to the nanometer scale does not always lead the performance improvement mainly due to the reduced thickness and area for the light absorption. However, it is still possible to circumvent the drawback by introducing the optical antenna and to improve the performance by miniaturization. Moreover, the nanometer-scale photodetectors exhibits unique functionalities such as incident angle detection and biosensing. In this report, some examples found in the photodiode with SP antenna, MOSFET single-photon detector, SET-based ultrahigh-frequency rectifier, and terahertz bolometer are introduced. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Photons

来源：评论

学校读者我要写书评

暂无评论

Penrose Super-Radiance in a Synthetically Rotating Metasurface

Penrose Super-Radiance in a Synthetically Rotating Metasurfa...

引用

2022 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, AP-S/URSI 2022

作者： Moussa, Hady Alù, Andrea City University of New York Photonics Initiative Advanced Science Research Center New York10031 United States City College of the City University of New York Department of Electrical Engineering New York10031 United States City University of New York Physics Program Graduate Center New YorkNY10016 United States

ISBN: (数字)9781665496582

ISBN: (纸本)9781665496582

Super-radiant amplification of scattering in a rotating medium was predicted by Sir Penrose as an exotic astrophysics phenomenon. Here we demonstrate its electromagnetic analogue using spatio-temporally modulated metasurfaces that experience a form of synthetic rotation. We consider excitations with signals carrying orbital angular momentum (OAM), highly beneficial for multiplexed wireless networks that demand high data rate capacity. The metasurface efficiently couples and can amplify selected OAM orders based on a phenomenon analogous to Penrose super-radiance. We build, analyze, and simulate a single circuit element, modulated in time through varactors, that efficiently manipulates three OAM orders and selectively amplifies them. We then show the possibility of observing angular Doppler shift and amplifying selected OAM signals using an array of these elements forming a metasurface. © 2022 IEEE.

关键词： Astrophysics

来源：评论

学校读者我要写书评

暂无评论

A Distributed Task Allocation Protocol for Cooperative Multi-UAV Search and Rescue Systems

A Distributed Task Allocation Protocol for Cooperative Multi...

引用

2021 International Conference on Unmanned Aircraft Systems, ICUAS 2021

作者： De Freitas, Edison Pignaton Basso, Maik Da Silva, Antonio Arlis Santos Vizzotto, Marcos Rodrigues Correa, Mateus Schein Cavalheiro Federal University of Rio Grande Do sul Graduate Program in Electrical Engineering Porto Alegre Brazil Federal University of Rio Grande Do sul Graduate Program in Computer Science Porto Alegre91.501-970 Brazil Federal University of Rio Grande Do sul Department of Electric Automation and Energy Porto Alegre Brazil

ISBN: (纸本)9780738131153

Nowadays, applications involving multiple robotic systems connected through a wireless network - to perform tasks together - have an increased research interest. Unmanned Aerial Vehicles (UAVs) are excellent tools for evaluating and surveying distributed robotic systems applications due to their flexibility and three-dimensional mobility capability. Cooperative systems composed of multiples UAVs may have a centralized coordination which assists the members of a team to make their decisions in a distributed manner regarding the tasks to be performed. This paper proposes a system composed of embedded hardware and a high-level communication protocol that serves as a basis for identifying, distributing, and allocating tasks in a simple and distributed way to be used by groups of UAVs. The proposal is evaluated in a search and rescue scenario. The setup is configured with two types of UAVs - namely, searchers (search for new tasks) and workers (execution of tasks). Also, a set of nine simulation experiments covering three different setups were performed. Then the proposal is evaluated by two sets of field experiments with real vehicles. The obtained results in the proposed experiments demonstrate that the system can be successfully used in the proposed scenario for task distribution and allocation. © 2021 IEEE.

关键词： Antennas

来源：评论

学校读者我要写书评

暂无评论

Improvement of clinical wound microcirculation diagnosis using an object tracking-based laser speckle contrast imaging system

引用

APL Bioengineering 2024年第1期8卷 016105页

作者： Hsieh, Meng-Che Chang, Chia-Yu Hsu, Ching-Han Lin, Yan-Ren Hsieh, Pei-You Ching, Congo Tak-Shing Liao, Lun-De Institute of Biomedical Engineering and Nanomedicine National Health Research Institutes 35 Keyan Road Zhunan Town Miaoli County 35053 Taiwan Program in Tissue Engineering and Regenerative Medicine National Chung Hsing University 145 Xingda Road South District Taichung402 Taiwan Department of Biomedical Engineering and Environmental Sciences National Tsing Hua University No. 101 Section 2 Kuang-Fu Road Hsinchu30013 Taiwan Department of Emergency and Critical Care Medicine Changhua Christian Hospital Changhua Taiwan Graduate Institute of Biomedical Engineering National Chung Hsing University 145 Xingda Road South District Taichung402 Taiwan Department of Electrical Engineering National Chi Nan University 1 University Road Puli Township Nantou County 545301 Taiwan

Wound monitoring is crucial for effective healing, as nonhealing wounds can lead to tissue ulceration and necrosis. Evaluating wound recovery involves observing changes in angiogenesis. Laser speckle contrast imaging (LSCI) is vital for wound assessment due to its rapid imaging, high resolution, wide coverage, and noncontact properties. When using LSCI equipment, regions of interest (ROIs) must be delineated in lesion areas in images for quantitative analysis. However, patients with serious wounds cannot maintain constant postures because the affected areas are often associated with discomfort and pain. This leads to deviations between the drawn ROI and actual wound position when using LSCI for wound assessment, affecting the reliability of relevant assessments. To address these issues, we used the channel and spatial reliability tracker object tracking algorithm to develop an automatic ROI tracking function for LSCI systems. This algorithm is used to track and correct artificial movements in blood flow images, address the ROI position offset caused by the movement of the affected body part, increase the blood flow analysis accuracy, and improve the clinical applicability of LSCI systems. ROI tracking experiments were performed by simulating wounds, and the results showed that the intraclass correlation coefficient (ICC) ranged from 0.134 to 0.976. Furthermore, the object within the ROI affected tracking performance. Clinical assessments across wound types showed ICCs ranging from 0.798 to 0.917 for acute wounds and 0.628-0.849 for chronic wounds. We also discuss factors affecting tracking performance and propose strategies to enhance implementation effectiveness. © 2024 Author(s).

关键词： Image enhancement

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：