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Deep Learning Methods for Calibrated Photometric Stereo and Beyond

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arXiv 2022年

作者： Ju, Yakun Lam, Kin-Man Xie, Wuyuan Zhou, Huiyu Dong, Junyu Shi, Boxin School of Electrical and Electronic Engineering Nanyang Technological University Singapore The Department of Electrical and Electronic Engineering The Hong Kong Polytechnic University Hong Kong The Research Institute for Future Media Computing Shenzhen University Shenzhen China The Department of Informatics University of Leicester Leicester United Kingdom The Faculty of Information Science and Engineering The Institute for Advanced Ocean Study Ocean University of China Qingdao China The National Key Laboratory for Multimedia Information Processing National Engineering Research Center of Visual Technology School of Computer Science Peking University Beijing China

Photometric stereo recovers the surface normals of an object from multiple images with varying shading cues, i.e., modeling the relationship between surface orientation and intensity at each pixel. Photometric stereo prevails in superior per-pixel resolution and fine reconstruction details. However, it is a complicated problem because of the non-linear relationship caused by non-Lambertian surface reflectance. Recently, various deep learning methods have shown a powerful ability in the context of photometric stereo against non-Lambertian surfaces. This paper provides a comprehensive review of existing deep learning-based calibrated photometric stereo methods utilizing orthographic cameras and directional light sources. We first analyze these methods from different perspectives, including input processing, supervision, and network architecture. We summarize the performance of deep learning photometric stereo models on the most widely-used benchmark data set. This demonstrates the advanced performance of deep learning-based photometric stereo methods. Finally, we give suggestions and propose future research trends based on the limitations of existing models. Copyright © 2022, The Authors. All rights reserved.

关键词： Light sources

Efficient Qubit Calibration by Binary-Search Hamiltonian Tracking

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arXiv 2025年

作者： Berritta, Fabrizio Benestad, Jacob Pahl, Lukas Mathews, Melvin Krzywda, Jan A. Assouly, Réouven Sung, Youngkyu Kim, David K. Niedzielski, Bethany M. Serniak, Kyle Schwartz, Mollie E. Yoder, Jonilyn L. Chatterjee, Anasua Grover, Jeffrey A. Danon, Jeroen Oliver, William D. Kuemmeth, Ferdinand Research Laboratory of Electronics Massachusetts Institute of Technology CambridgeMA02139 United States Center for Quantum Devices Niels Bohr Institute University of Copenhagen Copenhagen2100 Denmark Center for Quantum Spintronics Department of Physics Norwegian University of Science and Technology TrondheimNO-7491 Norway Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA02139 United States Department of Information Technology and Electrical Engineering ETH Zürich Zürich8093 Switzerland 〈aQaL〉 Applied Quantum Algorithms — Lorentz Insitute for Theoretical Physics & Leiden Institute of Advanced Computer Science Universiteit Leiden Netherlands Lincoln Laboratory Massachusetts Institute of Technology LexingtonMA02421 United States QuTech and Kavli Institute of Nanoscience Delft University of Technology Delft Netherlands Department of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Institute of Experimental and Applied Physics University of Regensburg Regensburg93040 Germany QDevil Quantum Machines Ballerup2750 Denmark

We present a real-time method for calibrating the frequency of a resonantly driven qubit. The real-time processing capabilities of a classical controller dynamically generate adaptive probing sequences for qubit-frequency estimation. Each probing evolution time and drive frequency are calculated to divide the prior probability distribution into two branches, following a locally optimal strategy that mimics a conventional binary search. We show the algorithm’s efficacy by stabilizing a flux-tunable transmon qubit, leading to improved coherence and gate fidelity. By feeding forward the updated qubit frequency, the FPGA-powered control electronics partially mitigates non-Markovian noise in the system, which is detrimental to quantum error correction. Our protocol highlights the importance of feedback in improving the calibration and stability of qubits subject to drift and can be readily applied to other qubit platforms. © 2025, CC BY.

关键词： Hamiltonians

Achievable Diversity Order of HARQ-Aided Downlink NOMA systems

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arXiv 2022年

作者： Shi, Zheng Zhang, Chenmeng Fu, Yaru Wang, Hong Yang, Guanghua Ma, Shaodan The Institute of Physical Internet The School of Intelligent Systems Science and Engineering Jinan University Zhuhai519070 China The School of Telecommunications Engineering Xidian University Xi’an710000 China The Department of Information Systems Technology and Design Singapore University of Technology and Design Singapore The School of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China The National Mobile Communications Research Laboratory Southeast University Nanjing210096 China The State Key Laboratory of Internet of Things for Smart City The Department of Electrical and Computer Engineering University of Macau China

The combination between non-orthogonal multiple access (NOMA) and hybrid automatic repeat request (HARQ) is capable of realizing ultra-reliability, high throughput and many concurrent connections particularly for emerging communication systems. This paper focuses on characterizing the asymptotic scaling law of the outage probability of HARQ-aided NOMA systems with respect to the transmit power, i.e., diversity order. The analysis of diversity order is carried out for three basic types of HARQ-aided downlink NOMA systems, including Type I HARQ, HARQ with chase combining (HARQ-CC) and HARQ with incremental redundancy (HARQ-IR). The diversity orders of three HARQ-aided downlink NOMA systems are derived in closed-form, where an integration domain partition trick is developed to obtain the bounds of the outage probability specially for HARQ-CC and HARQ-IR-aided NOMA systems. The analytical results show that the diversity order is a decreasing step function of transmission rate, and full time diversity can only be achieved under a sufficiently low transmission rate. It is also revealed that HARQ-IR-aided NOMA systems have the largest diversity order, followed by HARQ-CC-aided and then Type I HARQ-aided NOMA systems. Additionally, the users’ diversity orders follow a descending order according to their respective average channel gains. Furthermore, we expand discussions on the cases of power-efficient transmissions and imperfect channel state information (CSI). Monte Carlo simulations finally confirm our analysis. © 2022, CC BY.

关键词： Monte Carlo methods

Observation of disorder-free localization and efficient disorder averaging on a quantum processor

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arXiv 2024年

作者： Gyawali, G. Cochran, T. Lensky, Y.D. Rosenberg, E. Karamlou, A.H. Kechedzhi, K. Berndtsson, J. Westerhout, T. Asfaw, A. Abanin, D. Acharya, R. Aghababaie Beni, L. Andersen, T.I. Ansmann, M. Arute, F. Arya, K. Astrakhantsev, N. Atalaya, J. Babbush, R. Ballard, B. Bardin, J. Bengtsson, A. Bilmes, A. Bortoli, G. Bourassa, A. Bovaird, J. Brill, L. Broughton, M. Browne, D. Buchea, B. Buckley, B. Buell, D. Burger, T. Burkett, B. Bushnell, N. Cabrera, A. Campero, J. Chang, H.-S. Chen, Z. Chiaro, B. Claes, J. Cleland, A. Cogan, J. Collins, R. Conner, P. Courtney, W. Crook, A.L. Das, S. Debroy, D.M. Del Toro Barba, A. Demura, S. De Lorenzo, L. Di Paolo, A. Donohoe, P. Drozdov, I. Dunsworth, A. Earle, C. Eickbusch, A. Elbag, A. Elzouka, M. Erickson, C. Faoro, L. Fatemi, R. Ferreira, V. Flores Burgos, L. Forati, E. Fowler, A. Foxen, B. Ganjam, S. Gasca, R. Giang, W. Gidney, C. Gilboa, D. Gosula, R. Grajales Dau, A. Graumann, D. Greene, A. Gross, J. Habegger, S. Hamilton, M. Hansen, M. Harrigan, M. Harrington, S. Heslin, S. Heu, P. Hill, G. Hilton, J. Hoffmann, M. Huang, H.-Y. Huff, A. Huggins, W.J. Ioffe, L.B. Isakov, S.V. Jeffrey, E. Jiang, Z. Jones, C. Jordan, S. Joshi, C. Juhas, P. Kafri, D. Kang, H. Khaire, T. Khattar, T. Khezri, M. Kieferová, M. Kim, S. Klimov, P. Klots, A. Kobrin, B. Korotkov, A. Kostritsa, F. Kreikebaum, J. Kurilovich, V. Landhuis, D. Langley, B. Laptev, P. Lau, K.-M. Ledford, J. Lee, J. Lee, K. Lester, B. Le Guevel, L. Li, W. Lill, A. Liu, W. Livingston, W. Locharla, A. Lundahl, D. Lunt, A. Madhuk, S. Maloney, A. Mandrà, S. Martin, L. Martin, S. Martin, O. Maxfield, C. McClean, J. McEwen, M. Meeks, S. Megrant, A. Mi, X. Miao, K. Mieszala, A. Molina, S. Montazeri, S. Morvan, A. Movassagh, R. Neill, C. Nersisyan, A. Newman, M. Nguyen, A. Nguyen, M. Ni, C.-H. Ottosson, K. Pizzuto, A. Potter, R. Pritchard, O. Pryadko, L. Quintana, C. Reagor, M. Rhodes, D. Roberts, G. Rocque, C. Rubin, N. Saei, N. Google Research Mountain ViewCA United States Department of Physics Cornell University IthacaNY United States Laboratory of Solid State and Atomic Physics Cornell University IthacaNY United States Department of Physics Princeton University PrincetonNJ United States Institute of Molecules and Materials Radboud University Nijmegen Netherlands Department of Electrical and Computer Engineering University of Massachusetts AmherstMA United States Department of Physics University of Connecticut StorrsCT United States Department of Electrical and Computer Engineering Auburn University AuburnAL United States QSI Faculty of Engineering & Information Technology University of Technology Sydney NSW Australia Department of Electrical and Computer Engineering University of California RiversideCA United States Department of Chemistry and Chemical Biology Harvard University United States Department of Physics and Astronomy University of California RiversideCA United States Laboratory of Theoretical Physics and Modelling CY Cergy Paris Universite UMR CNRS 8089 Pontoise Cergy-Pontoise Cedex France Technical University of Munich TUM School of Natural Sciences Physics Department TQM Garching Germany Munich Germany Blackett Laboratory Imperial College London LondonSW7 2AZ United Kingdom Max Planck Institute of Quantum Optics Garching Germany Department of Physics Arnold Sommerfeld Center for Theoretical Physics Ludwig Maximilian University of Munich Munich Germany Max Planck Institute for the Physics of Complex Systems Dresden Germany

One of the most challenging problems in the computational study of localization in quantum many-body systems is to capture the effects of rare events, which requires sampling over exponentially many disorder realizations. We implement an efficient procedure on a quantum processor, leveraging quantum parallelism, to efficiently sample over all disorder realizations. We observe localization without disorder in quantum many-body dynamics in one and two dimensions: perturbations do not diffuse even though both the generator of evolution and the initial states are fully translationally invariant. The disorder strength as well as its density can be readily tuned using the initial state. Furthermore, we demonstrate the versatility of our platform by measuring Rényi entropies. Our method could also be extended to higher moments of the physical observables and disorder learning. © 2024, CC BY.

关键词： Quantum electronics

A Zeroth-Order Momentum Method for Risk-Averse Online Convex Games

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arXiv 2022年

作者： Wang, Zifan Shen, Yi Bell, Zachary I. Nivison, Scott Zavlanos, Michael M. Johansson, Karl H. Division of Decision and Control Systems School of Electrical Enginnering and Computer Science KTH Royal Institute of Technology StockholmSE-10044 Sweden The Department of Mechanical Engineering and Materials Science Duke University DurhamNC United States The Air Force Research Laboratory Eglin AFB FL United States

We consider risk-averse learning in repeated unknown games where the goal of the agents is to minimize their individual risk of incurring significantly high cost. Specifically, the agents use the conditional value at risk (CVaR) as a risk measure and rely on bandit feedback in the form of the cost values of the selected actions at every episode to estimate their CVaR values and update their actions. A major challenge in using bandit feedback to estimate CVaR is that the agents can only access their own cost values, which, however, depend on the actions of all agents. To address this challenge, we propose a new risk-averse learning algorithm with momentum that utilizes the full historical information on the cost values. We show that this algorithm achieves sub-linear regret and matches the best known algorithms in the literature. We provide numerical experiments for a Cournot game that show that our method outperforms existing methods. © 2022, CC BY.

关键词： Learning algorithms

Application-level Benchmarking of Quantum computers using Nonlocal Game Strategies

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arXiv 2023年

作者： Furches, Jim Chehade, Sarah Hamilton, Kathleen Wiebe, Nathan Marrero, Carlos Ortiz College of Computing Georgia Institute of Technology AtlantaGA30332 United States Physical Detection Systems and Deployment Division Pacific Northwest National Laboratory RichlandWA99354 United States Quantum Computational Science Group Oak Ridge National Laboratory Oak RidgeTN37830 United States Department of Computer Science University of Toronto ONM5S 1A1 Canada High Performance Computing Group Pacific Northwest National Laboratory RichlandWA99354 United States Canadian Institute for Advanced Research TorontoONM5G 1M1 Canada Department of Electrical & Computer Engineering North Carolina State University RaleighNC27607 United States

In a nonlocal game, two noncommunicating players cooperate to convince a referee that they possess a strategy that does not violate the rules of the game. Quantum strategies allow players to optimally win some games by performing joint measurements on a shared entangled state, but computing these strategies can be challenging. We present a variational quantum algorithm to compute quantum strategies for nonlocal games by encoding the rules of a nonlocal game into a Hamiltonian. We show how this algorithm can generate a short-depth optimal quantum strategy for a graph coloring game with a quantum advantage. This quantum strategy is then evaluated on fourteen different quantum hardware platforms to demonstrate its utility as a benchmark. Finally, we discuss potential sources of errors that can explain the observed decreased performance of the executed task and derive an expression for the number of samples required to accurately estimate the win rate in the presence of noise. Copyright © 2023, The Authors. All rights reserved.

关键词： Qubits

A Pricing Rule for Third-Party Platoon Coordination Service Provider

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A Pricing Rule for Third-Party Platoon Coordination Service ...

Asian Control Conference

作者： Ting Bai Alexander Johansson Shaoyuan Li Karl Henrik Johansson Jonas Må rtensson Integrated Transport Research Lab Digital Futures and Division of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Stockholm Sweden Department of Automation Key Laboratory of System Control and Information Processing Ministry of Education Shanghai Jiao Tong University Shanghai China

We model a platooning system including trucks and a third-party service provider that performs platoon coordination, distributes the platooning profit within platoons, and charges the trucks in exchange for its services. This paper studies one class of pricing rules, where the third-party service provider keeps part of the platooning profit each time a platoon is formed. Furthermore, we propose a platoon coordination solution based on distributed model predictive control in which the pricing rule is integrated. To evaluate the effect of the pricing on the platooning system, we perform a simulation over the Swedish road network. The simulation shows that the platooning rate and profit highly depend on the pricing. This suggests that pricing needs to be set carefully to obtain a satisfactory platooning system in the future.

关键词： Roads Pricing Predictive control

Effect of Absorption of Patch Antenna Signals on Increasing the Head Temperature

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computer Modeling in engineering & Sciences 2020年第8期124卷 683-701页

作者： Mohamed Abbas Ali Algahtani Amir Kessentini Hassen Loukil Muneer Parayangat Thafasal Ijyas Abdul Wase Mohammed Electrical Engineering Department College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Mechanical Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Computers and Communications College of EngineeringDelta University for Science and TechnologyGamasa35712Egypt Laboratory of Electromechanical Systems(LASEM) National Engineering School of SfaxUniversity of SfaxSfax3038Tunisia Electronics and Information Technology Laboratory University of SfaxNational Engineering School of SfaxSfax3038Tunisia Research Center for Advanced Materials Science King Khalid UniversityAbha61413Saudi Arabia Nabeul’s Foundation Institute for Engineering Studies University of CarthageIPEINNabeul8000Tunisia

Every new generation of antennas is characterized by increased accuracy and faster transmission ***,patch antennas have been known to damage human *** type of antenna sends out electromagnetic waves that increase the temperature of the human head and prevent nerve strands from functioning *** paper examines the effect of the communication between the patch antenna and the brain on the head’s temperature by developing a hypothetical multi-input model that achieves more accurate *** inputs are an individual’s blood and tissue,and the emission power of the *** forces depend on the permeability and conductivity characteristics of the metal from which the antenna is *** proposed model is the first one that links the material the antenna is manufactured from and the head’s *** results show that there are only a small number of materials that should be used as antenna *** materials are in the form of thin *** using these thin films at different temperatures,the risk to the head can be *** paper finds that the best results were obtained when the patch antenna was made of one of the following materials operating at a specific temperature:traditional materials at 305°K;casting cast steel at around 295°K;bismuth telluride(Bi2Te3)at 290°K;or barium sodium niobate at 310°K.

关键词： Brain patch antenna head overheating waves behavior materials properties

Joint Design of Access and Backhaul in Densely Deployed MmWave Small Cells

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arXiv 2023年

作者： Guo, Ziqi Niu, Yong Mao, Shiwen He, Ruisi Wang, Ning Zhong, Zhangdui Ai, Bo State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong University Beijing100044 China Collaborative Innovation Center of Railway Traffic Safety Beijing Jiaotong University Beijing100044 China Department of Electrical and Computer Engineering Auburn University AuburnAL36849-5201 United States Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing Jiaotong University Beijing100044 China School of Information Engineering Zhengzhou University Zhengzhou450001 China

With the rapid growth of mobile data traffic, the shortage of radio spectrum resource has become increasingly prominent. Millimeter wave (mmWave) small cells can be densely deployed in macro cells to improve network capacity and spectrum utilization. Such a network architecture is referred to as mmWave heterogeneous cellular networks (HetNets). Compared with the traditional wired backhaul, The integrated access and backhaul (IAB) architecture with wireless backhaul is more flexible and cost-effective for mmWave HetNets. However, the imbalance of throughput between the access and backhaul links will constrain the total system throughput. Consequently, it is necessary to jointly design of radio access and backhaul link. In this paper, we study the joint optimization of user association and backhaul resource allocation in mmWave HetNets, where different mmWave bands are adopted by the access and backhaul links. Considering the non-convex and combinatorial characteristics of the optimization problem and the dynamic nature of the mmWave link, we propose a multi-agent deep reinforcement learning (MADRL) based scheme to maximize the long-term total link throughput of the network. The simulation results show that the scheme can not only adjust user association and backhaul resource allocation strategy according to the dynamics in the access link state, but also effectively improve the link throughput under different system configurations. Copyright © 2023, The Authors. All rights reserved.

关键词： Reinforcement learning