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Continuous and Incremental Learning in physical Human-Robot Cooperation using Probabilistic Movement Primitives

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Continuous and Incremental Learning in physical Human-Robot ...

IEEE International Workshop on Robot and Human Communication (ROMAN)

作者： Daniel Schäle Martin F. Stoelen Erik Kyrkjebø Department of Computer Science Electrical Engineering and Mathematical Sciences Faculty of Engineering and Science Western Norway University of Applied Sciences Førde Norway CRNS University of Plymouth Plymouth United Kingdom

ISBN: (数字)9781728188591

ISBN: (纸本)9781665406802

For a successful deployment of physical Human-Robot Cooperation (pHRC), humans need to be able to teach robots new motor skills quickly. Probabilistic movement primitives (ProMPs) are a promising method to encode a robot’s motor skills learned from human demonstrations in pHRC settings. However, most algorithms to learn ProMPs from human demonstrations operate in batch mode, which is not ideal in pHRC when we want humans and robots to work together from even the first demonstration. In this paper, we propose a new learning algorithm to learn ProMPs incre-mentally and continuously in pHRC settings. Our algorithm incorporates new demonstrations sequentially as they arrive, allowing humans to observe the robot’s learning progress and incrementally shape the robot’s motor skill. A built-in forgetting factor allows for corrective demonstrations resulting from the human’s learning curve or changes in task constraints. We compare the performance of our algorithm to existing batch ProMP algorithms on reference data generated from a pick-and-place task at our lab. Furthermore, we demonstrate how the forgetting factor allows us to adapt to changes in the task. The incremental learning algorithm presented in this paper has the potential to lead to a more intuitive learning progress and to establish a successful cooperation between human and robot faster than training in batch mode.

关键词： Training Shape Probabilistic logic Task analysis Robots

Epitaxial lattice-matched Al0.89Sc0.11N/GaN distributed Bragg reflectors

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arXiv 2023年

作者： van Deurzen, Len Nguyen, Thai-Son Casamento, Joseph Xing, Huili Grace Jena, Debdeep School of Applied and Engineering Physics Cornell University IthacaNY14853 United States Department of Materials Science and Engineering Cornell University IthacaNY14853 United States Department of Electrical and Computer Engineering Cornell University IthacaNY14853 United States Kavli Institute Cornell for Nanoscale Science Cornell University IthacaNY14853 United States

We demonstrate epitaxial lattice-matched Al0.89Sc0.11N/GaN ten and twenty period distributed Bragg reflectors (DBRs) grown on c-plane bulk n-type GaN substrates by plasma-enhanced molecular beam epitaxy (PA-MBE). Resulting from a rapid increase of in-plane lattice coefficient as scandium is incorporated into AlScN, we measure a lattice-matched condition to c-plane GaN for a Sc content of just 11%, resulting in a large refractive index mismatch Δn greater than 0.3 corresponding to an index contrast of Δn/nGaN = 0.12 with GaN. The DBRs demonstrated here are designed for a peak reflectivity at a wavelength of 400 nm reaching a reflectivity of 0.98 for twenty periods. It is highlighted that AlScN/GaN multilayers require fewer periods for a desired reflectivity than other lattice-matched Bragg reflectors such as those based on AlInN/GaN multilayers. © 2023, CC BY-NC-ND.

关键词： Gallium nitride

Experimental observation of ballistic to diffusive transition in AlN thin films

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arXiv 2024年

作者： Hoque, Md Shafkat Bin Liao, Michael E. Zare, Saman Liu, Zeyu Koh, Yee Rui Huynh, Kenny Shi, Jingjing Graham, Samuel Luo, Tengfei Ahmad, Habib Doolittle, W. Alan Goorsky, Mark S. Hopkins, Patrick E. Department of Mechanical and Aerospace Engineering University of Virginia CharlottesvilleVA22904 United States Department of Materials Science and Engineering University of California Los AngelesCA90095 United States Department of Applied Physics Hunan University Changsha410300 China George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology AtlantaGA30332 United States School of Materials Science and Engineering Georgia Institute of Technology AtlantaGA30332 United States Department of Aerospace and Mechanical Engineering University of Notre Dame Notre DameIN46556 United States School of Electrical and Computer Engineering Georgia Institute of Technology AtlantaGA30332 United States Department of Materials Science and Engineering University of Virginia CharlottesvilleVA22904 United States Department of Physics University of Virginia CharlottesvilleVA22904 United States

Bulk AlN possesses high thermal conductivity due to long phonon mean-free-paths, high group velocity, and long lifetimes. However, the thermal transport scenario becomes very different in a thin AlN film due to phonon-defect and phonon-boundary scattering. Herein, we report experimental observation of ballistic to diffusive transition in a series of AlN thin films (1.6 - 2440 nm) grown on sapphire substrates. The ballistic transport is characterized by constant thermal resistance as a function of film thickness due to phonon scattering by defects and boundaries. In this transport regime, phonons possess very small group velocities and lifetimes. The lifetime of the optical phonons increases by more than an order of magnitude in the diffusive regime, however, remains nearly constant afterwards. Our study is important for understanding the details of nano and microscale thermal transport in a highly conductive material. Copyright © 2024, The Authors. All rights reserved.

关键词： Sapphire

Shunt Capacitor Bank Fault Detection and Localization Using Sub-Cycle Algorithm

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Shunt Capacitor Bank Fault Detection and Localization Using ...

IEEE Canada Electric Power Conference, EPEC

作者： Mohsen Tajdinian Behzad Behdani Ali Goodarzi Harold R. Chamorro Vijay K. Sood Department of Power and Control Engineering School of Electrical and Computer Engineering Shiraz University Shiraz Iran Faculty of Electrical Engineering Mathematics and Computer Science Delft University of Technology Delft the Netherlands Fars Electricity Distribution Company Fars Iran School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Stockholm Sweden Department of Electrical Computer and Software Engineering Faculty of Engineering and Applied Science Ontario Tech University Ontario Canada

ISBN: (纸本)9781665463195

Fast internal detection and location in Shunt Ca-pacitor Banks (SCBs) can lead to the prevention of damages to other SCBs' elements and consequently avoid undesirable performance and effects in power system operation. This paper targets the performance of phasor-based algorithms of failure detection and fault location of SCBs. Being dependent on the fundamental phasor components which usually are calculated based on the Discrete Fourier Transform (DFT), the failure detection and fault location algorithms suffer from almost one-cycle delay. This paper provides sub-cycle phasor estimation based on the least-square technique. The proposed algorithm is evaluated for different configurations of SCBs considering different fuse protection designs. The proposed method provides a criterion for relay decision-making in the case of multiple faulty phases condition. The proposed method is designed to monitor and detect consecutive failures based on the existing data of commercial relays. Performance evaluations are conducted under different circumstances namely voltage unbalance conditions and multiple internal fault locations.

关键词： Performance evaluation Fault detection Capacitors Discrete Fourier transforms Estimation Voltage Fault location

All-Dielectric Huygens’ Metawaveguides for Nonlinear Integrated Photonics

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All-Dielectric Huygens’ Metawaveguides for Nonlinear Integr...

2024 Nonlinear Photonics, NP 2024

作者： Flizikowski, G.A.S. Oner, O.W. dos Santos, L.F. Bin-Alam, M.S. Pertsch, T. Staude, I. Schmid, J.H. Cheben, P. Dolgaleva, K. School of Electrical Engineering and Computer Science University of Ottawa OttawaONK1N 6N5 Canada Department of Physics University of Ottawa OttawaONK1N 6N5 Canada National Research Council of Canada OttawaONK1A 0R6 Canada Institute of Applied Physics Abbe Center of Photonics Friedrich-Schiller-Universität Jena Jena07745 Germany

We have experimentally demonstrated the compensation of nonlinear optical effects by a silicon-on-insulator nanophotonic metawaveguide comprising a chain of resonantly forward-scattering nanoparticles, exhibiting soli... 详细信息

关键词： Forward scattering

Strategies of Collaborative Filtering Recommendation Mechanism Using a Deep Learning Approach 3

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Strategies of Collaborative Filtering Recommendation Mechani...

3rd IEEE Eurasia Conference on IOT, Communication and engineering, ECICE 2021

作者： Chang, Chin-Chih Chang, Huan-Ming Chung Hua University Becholar Program in Applied Foreign Language and Smart Commerce Hsinchu30012 Taiwan Chung Hua University Department of Computer Science and Information Engineering Hsinchu30012 Taiwan

ISBN: (纸本)9781665445160

Nowadays, recommendation systems are widely used to help users locate the items they want. Collaborative filtering (CF) is a commonly used method for the recommendation. CF techniques use user-item ratings for prediction but suffer from the problems of data sparsity, cold start, and scalability. Though the Matrix Factorization (MF) techniques like Singular Value Decomposition (SVD) or Principal Component Analysis (PCA) overcome the above-mentioned problems, these methods are possible to deliver unmeaningful results in the condition of a low ranked approximation and denser singular vectors. In this paper, we review strategies of collaborative filtering recommendation mechanisms and propose an approach based on an autoencoder of convolutional neural network. Autoencoders are unsupervised learning methods in which neural networks are supported for the task of representation learning. We identify the user's features through learning, and then use these features to combine the collaborative filtering algorithm to recommend items. The experimental results show that the convolutional autoencoder can effectively reduce the computations when the amount of data is huge and benefited from the performance of its convolutional neural network. © 2021 IEEE.

关键词： Recommender systems

Optical scanning endoscope via a single multimode optical fiber

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Opto-Electronic science 2024年第3期3卷 1-32页

作者： Guangxing Wu Runze Zhu Yanqing Lu Minghui Hong Fei Xu Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3117576Singapore College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210023China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen University33 Qunxian RoadXiamen 361005China

Optical endoscopy has become an essential diagnostic and therapeutic approach in modern biomedicine for directly observing organs and tissues deep inside the human body,enabling non-invasive,rapid diagnosis and *** fiber endoscopy is highly competitive among various endoscopic imaging techniques due to its high flexibility,compact structure,excellent resolution,and resistance to electromagnetic *** the past decade,endoscopes based on a single multimode optical fiber(MMF)have attracted widespread research interest due to their potential to significantly reduce the footprint of optical fiber endoscopes and enhance imaging *** comparison with other imaging principles of MMF endoscopes,the scanning imaging method based on the wavefront shaping technique is highly developed and provides benefits including excellent imaging contrast,broad applicability to complex imaging scenarios,and good compatibility with various well-established scanning imaging *** this review,various technical routes to achieve light focusing through MMF and procedures to conduct the scanning imaging of MMF endoscopes are *** advancements in imaging performance enhancements,integrations of various imaging modalities with MMF scanning endoscopes,and applications are *** specific to this endoscopic imaging technology are analyzed,and potential remedies and avenues for future developments are discussed.

关键词： multimode optical fiber endoscope scanning imaging focusing wavefront shaping

Differentially Private Generalized Linear Models Revisited

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arXiv 2022年

作者： Arora, Raman Bassily, Raef Guzmán, Cristóbal Menart, Michael Ullah, Enayat Department of Computer Science The Johns Hopkins University United States The Ohio State University United States Department of Applied Mathematics University of Twente Institute for Mathematical and Computational Engineering Pontificia Universidad Católica de Chile Chile Department of Computer Science & Engineering The Ohio State University United States

We study the problem of (ϵ, δ)-differentially private learning of linear predictors with convex losses. We provide results for two subclasses of loss functions. The first case is when the loss is smooth and non-negative but not necessarily Lipschitz (such as the squared loss). For this case, we establish an upper bound on the excess population risk of e O (kw*√nk + minn w*2 (nϵ)2/3 , √dw*2 nϵ }), where n is the number of samples, d is the dimension of the problem, and w*is the minimizer of the population risk. Apart from the dependence on w*, our bound is essentially tight in all parameters. In particular, we show a lower bound of Ω(1 √n + minn{w*4/3 (nϵ)2/3 , √dw* nϵ }). We also revisit the previously studied case of Lipschitz losses [SSTT20]. For this case, we close the gap in the existing work and show that the optimal rate is (up to log factors) Θ({kw*√nk + min nkw*√nϵk , √rankw* nϵ }), where rank is the rank of the design matrix. This im- proves over existing work in the high privacy regime. Finally, our algorithms involve a private model selection approach that we develop to enable attaining the stated rates without a-priori knowledge of w*. © 2022, CC BY.

关键词：

Four-band effective square lattice model for Bernal-stacked bilayer graphene

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arXiv 2024年

作者： Chen, Szu-Chao Mreńca-Kolasińska, Alina Liu, Ming-Hao Department of Electro-Optical Engineering National Formosa University Yunlin Taiwan AGH University Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Krakow30-059 Poland National Cheng Kung University Tainan70101 Taiwan

Bernal-stacked bilayer graphene (BLG) provides an ideal basis for gate-controlled, and free of etching, electronic devices. Theoretical modeling of realistic devices is an essential part of research, however, simulations of large-scale BLG devices continue to be extremely challenging. Micrometer-sized systems are predominantly beyond the reach of the commonly used atomistic tight-binding method, while other numerical approaches based on the two dimensional Dirac equation are not straightforward to conduct due to the fermion doubling problem. Here we present an approach based on the continuum model, unharmed by the fermion doubling. The discretization of the BLG continuum Hamiltonian leads to an effective four-band model, with both valleys built-in. We demonstrate its performance with realistic, large-scale systems, and obtain results consistent with experiments and with the tight-binding model, over a broad range of magnetic field. Copyright © 2024, The Authors. All rights reserved.

关键词： Etching