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Inverse design of figure eight fiber laser by artificial neural network

Optical Fiber Technology 2025年 94卷

作者： Mahdi Kasmi Abdullah S. Karar Ahmad Atieh Kaboko Jean-Jacques Monga Ehsan Adibnia Hafedh Mahmoud Zayani Mohamed Salhi Alexander Perepelov Faouzi Bahloul University of Carthage SERCOM Laboratory Tunisia Polytechnic School EPT B.P. 743 2078 Tunisia Optiwave Systems Inc 7 Capella Court Suite 900 Ottawa K2E 8A7 Ontario Canada Department of Electronics Carleton University 1125 Colonel By Drive Ottawa K1S 5B6 Ontario Canada University of Johannesburg Electrical and Electronic Engineering Science Department Auckland Park 2006 South Africa Faculty of Electrical and Computer Engineering University of Sistan and Baluchestan (USB) P.O. Box *** Zahedan Iran Department of Electrical Engineering College of Engineering Northern Border University Arar Saudi Arabia Univ Angers LPHIA SFR MATRIX F-49000 Angers France Skolkovo Institute of Science and Technology Bolshoy Boulevard 30 Building 1 Moscow 121205 Russia University of Tunis El Manar National Engineering School of Tunis B.P. 37 1002 Tunisia

Fiber lasers have become indispensable tools in modern photonics, offering unparalleled efficiency, stability, and versatility. Among them, the figure-eight fiber laser (F8FL) has gained prominence for its ability to generate ultra-short pulses with high peak power, making it highly suitable for applications in ultrafast spectroscopy, nonlinear microscopy, and optical frequency comb generation. However, designing and optimizing F8FLs remains a significant challenge due to the intricate interplay of nonlinear effects, dispersion management, and gain dynamics. Traditional design approaches rely on numerical simulations and iterative experimental tuning, which are computationally expensive and often yield suboptimal results. To address these challenges, we introduce a machine learning-based inverse design framework for optimizing F8FL parameters. Using a dataset generated from numerical simulations, an artificial neural network (ANN) is trained to establish a direct mapping between pulse characteristics and the key amplifier parameters, including small-signal gain and saturation energy. This approach enables rapid and accurate prediction of laser settings required to achieve a target pulse profile, significantly reducing the computational burden compared to conventional numerical methods. Our results demonstrate that the trained ANN model achieves excellent agreement with numerical simulations, effectively predicting the optimal parameters for producing high-energy rectangular pulses in the dissipative soliton resonance (DSR) regime. To validate the effectiveness of the predicted parameters, the ANN outputs were independently verified using OptiSystem simulations, confirming strong agreement with the desired pulse profiles. This study highlights the potential of machine learning in photonics, paving the way for the development of self-optimizing, adaptive laser systems with enhanced precision and efficiency. The proposed methodology can be extended to other nonlinear o

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Energy efficiency in qos constrained 60 ghz millimeter-wave ultra-dense networks 1

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14th EAI International Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, Qshine 2018

作者： Nguyen, Huy Thanh Murakami, Homare Nguyen, Kien Ishizu, Kentaro Kojima, Fumihide Kim, Jong-Deok Chung, Sang-Hwa Hwang, Won-Joo Department of Information and Communication System Inje University GimhaeGyeongnam621-749 Korea Republic of Wireless Systems Laboratory Wireless Networks Research Center National Institute of Information and Communications Technology Yokosuka239-0847 Japan School of Electrical and Computer Engineering Pusan National University Busan46241 Korea Republic of

ISBN: (数字)9783030144135

ISBN: (纸本)9783030144128

Millimeter-Wave (mmWave) communication in ultra-dense networks (UDNs) has been considered as a promising technology for future wireless communication systems. Exploiting the benefits of mmWave and UDNs, we introduce a new approach for jointly optimizing small-cell base station (SBS)-user (UE) association and power allocation to maximize the system energy efficiency (EE) while guaranteeing the quality of service (QoS) constraints for each UE. The SBS-UE association problem poses a new challenge since it reflects as a complex mixed-integer non-convex problem. On the other hand, the power allocation problem is in non-convexity structure, which is impossible to handle with the association problem concurrently. An alternating descent method is thus introduced to divide the primal optimization problem into two sub-problems and handle one-by-one at each iteration, where the SBS-UE association problem is reformulated using the penalty approach. Then, path-following algorithms are developed to convert non-convex problem into the simple convex quadratic functions at each iteration. Numerical results are provided to demonstrate the convergence and low-complexity of our proposed schemes. © ICST Institute for computer Sciences, Social Informatics and Telecommunications engineering 2019.

关键词： Convex optimization

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High-density implantable neural electrodes and chips for massive neural recordings

Brain-X

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Brain-X 2024年第2期2卷

作者： Wang, Longchun Suo, Yanxing Wang, Jiahao Wang, Xuanqi Xue, Kai An, Jingjing Sun, Xun Chen, Qinyu Tang, Xiaochen Zhao, Yang Ji, Bowen Liu, Jingquan Department of Micro/Nano Electronics Shanghai Jiao Tong University Shanghai China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong University Shanghai China DCI Joint Team Collaborative Innovation Center of IFSA Shanghai Jiao Tong University Shanghai China Unmanned System Research Institute Northwestern Polytechnical University Shaanxi Xi'an China National Key Laboratory of Unmanned Aerial Vehicle Technology Shaanxi Xi'an China Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical Engineering Northwestern Polytechnical University Shaanxi Xi'an China Institute of Guizhou Aerospace Measuring and Testing Technology Guizhou Guiyang China Leiden Institute of Advanced Computer Science (LIACS) Leiden University Leiden Netherlands Klipsch School of Electrical and Computer Engineering New Mexico State University Las Cruces NM United States

High-density neural recordings with superior spatiotemporal resolution powerfully unveil cellular-scale neural communication, showing great promise in neural science, translational medicine, and clinical applications. To achieve such, many design and fabrication innovations enhanced the electrode, chip, or both for biocompatibility improvement, electrical performance upgrade, and size miniaturization, offering several thousands of recording sites. However, an enormous gap exists along the trajectory toward billions of recording sites for brain scale resolution, posing many more design challenges. This review tries to find possible insight into mitigating the gap by discussing the latest progress in high-density electrodes and chips for neural recordings. It emphasizes the design, fabrication, bonding techniques, and in vivo performance optimization of high-density electrodes. It discusses the promising opportunities for circuit-level and architecture-level multi-channel chip design innovations. We expect that joint effort and close collaboration between high-density electrodes and chips will pave the way to high-resolution neural recording tools supporting cutting-edge neuroscience discoveries and applications. © 2024 The Author(s). Brain-X published by John Wiley & Sons Australia, Ltd on behalf of Ainuohui Medical Technology.

关键词： brain-computer interface high density implantable chips implantable electrodes massive neural recording

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Prototype Framework of Low-Latency Collection of Multi-Point Video Stream over Multi-Hop Multi-Channel Wireless Network

Prototype Framework of Low-Latency Collection of Multi-Point...

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作者： Aung Myo Htut Juseong Kim JongWon Kim Chaodit Aswakul Wireless Network and Future Internet Research Unit Department of Electrical Engineering Faculty of Engineering Chulalongkorn University Networked Computing Systems (NetCS) Laboratory School of Electrical Engineering and Computer Science Gwangju Institute of Science and Technology

Big cities are facing heavy road traffic congestion. The main reason is the increasing number of vehicles beyond the road network capacity, which forces traffic police at times to be incapable of controlling the inevitable traffic jams. To resolve those traffic jams, traffic police need the near real-time information of the road network e.g. from traffic cameras. In this paper, a prototype framework of low-latency collection of multi-point video streams over a multi-hop multi-channel wireless network is proposed. Video frames are captured by Raspberry Pi cameras and sent by the wireless link to the herein-called IoT Concentrators. IoTCloud Hub then pulls and stores those video frames from the IoT Concentrators. Users（traffic police） can watch traffic videos from the display screen of the IoT-Cloud Hub. As a proof-of-concept implementation, two Pi Cameras have been set up with Apache Kafka Producers and two additional Raspberry Pi's have been set up as the IoT Concentrators, which run the leader and follower Apache Kafka Brokers. To complete our system, an Intel NUC as IoT-Cloud Hub and another Intel NUC as Orchestration-Hub have been also set up. We assume the available wired communication linkage between the Orchestration-Hub and the other devices. However, the links between the Pi Cameras, IoT Concentrators and IoT-Cloud Hub are wireless with Wi-Fi. To achieve a high performance, multiple Wi-Fi channels can be dynamically configured by the Orchestration-Hub to steer the VDO traffic（based on TCP） away from the congested channels. Based on the implementation prototype, the average TCP throughputs over all the wireless links have been improved by 56.046% on average, compared with the case without the dynamic Wi-Fi channel selection.

关键词： Apache Kafka Raspberry Pi video streaming wireless

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Wide-angle giant photonic spin Hall effect

arXiv

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arXiv 2022年

作者： Chen, Zhihao Chen, Yu Wu, Yaodong Zhou, Xinxing Sun, Handong Low, Tony Chen, Hongsheng Lin, Xiao Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control Ministry of Education Synergetic Innovation Center for Quantum Effects and Applications School of Physics and Electronics Hunan Normal University Changsha410081 China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology Engineering Technology Research Center for 2D Material Information Function Devices and Systems of Guangdong Province Institute of Microscale Optoelectronics Shenzhen University Shenzhen518060 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 637371 Singapore School of Physical and Mathematical Sciences Nanyang Technological University 637371 Singapore Department of Electrical and Computer Engineering University of Minnesota MinneapolisMN55455 United States Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation ZJU-Hangzhou Global Scientific and Technological Innovation Center College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China International Joint Innovation Center ZJU-UIUC Institute The Electromagnetics Academy at Zhejiang University Zhejiang University Haining314400 China

Photonic spin Hall effect is a manifestation of spin-orbit interaction of light and can be measured by a transverse shift δ of photons with opposite spins. The precise measurement of transverse shifts can enable many spin-related applications, such as precise metrology and optical sensing. However, this transverse shift is generally small (i.e. δ/λ -1, λ is the wavelength), which impedes its precise measurement. To-date proposals to generate giant spin Hall effect (namely with δ/λ > 102) have severe limitations, particularly its occurrence only over a narrow angular cone (with a width of ∆0 70◦ by exploiting the interface between free space and uniaxial epsilon-near-zero media. The underlying mechanism is ascribed to the almost-perfect polarization splitting between s and p polarized waves at the designed interface. Remarkably, this almost-perfect polarization splitting does not resort to the interference effect and is insensitive to the incident angle, which then gives rise to the wide-angle giant photonic spin Hall effect. Copyright © 2022, The Authors. All rights reserved.

关键词： Polarization

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Sequential service restoration in distribution systems and microgrids integrating frequency response and varying switching interval 2

Sequential service restoration in distribution systems and m...

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2nd IEEE Texas Power and Energy Conference, TPEC 2018

作者： Bassey, Ogbonnaya Chen, Bo Butler-Purry, Karen L. Department of Electrical and Computer Engineering Texas AandM University United States Energy Systems Division Argonne National Laboratory United States

ISBN: (纸本)9781538610060

This paper presents a study of the application of a sequential service restoration method to single master operation microgrids with black start capability. Enhancements to a sequential service restoration methodology for frequency response characteristics during sequential load energization for diesel generators with isochronous governors were studied. Results were used to derive safe switching times during sequential service restoration for single master operation microgrid and informed the choice of maximum load step for the master distributed generators. The enhanced method was used to derive restoration sequences for a modified IEEE 123 node test feeder and an EMTP simulation in PSCAD was performed to verify the accuracy of the studies. © 2018 IEEE.

关键词： Frequency response

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A vision of the next-generation retail electricity market in the context of distributed energy resources

A vision of the next-generation retail electricity market in...

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2018 IEEE Power and Energy Society Innovative Smart Grid Technologies Conference, ISGT 2018

作者： Campos Do Prado, Josue Qiao, Wei Power and Energy Systems Laboratory Department of Electrical and Computer Engineering University of Nebraska-Lincoln LincolnNE68588-0511 United States

ISBN: (纸本)9781538624531

As distributed generation (DG) and smart grid technologies (SGTs) become more efficient and spread in the distribution grid, the number of agents taking advantage of such advances will continue to increase exponentially, making the next-generation retail electricity market more decentralized, competitive, and efficient. This growth will lead to the creation of new business models and transactive approaches to accommodate new agents, thus bringing new technical challenges concerning the security, reliability, and resilience of the transmission and distribution systems. This paper aims to present a vision of the next-generation retail electricity market by describing its expected characteristics, challenges, needs, and future research topics to be addressed. © 2018 IEEE.

关键词： Smart power grids

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Convex Relaxation with Log-Determinant Divergence-L1 Regularization for 3D Shape Reconstruction

Convex Relaxation with Log-Determinant Divergence-L1 Regular...

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第三十八届中国控制会议

作者： Wei Cao Luefeng Chen Min Wu Witold Pedrycz School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Department of Electrical and Computer Engineering University of Alberta

Investigated is the problem of estimating the 3 D shape of an object defined by a set of 3 D landmarks with their 2 D correspondences in a single image. To solve this problem, we use a dictionary of the basic shape with LDD-L1 regularization,which is the construction of the shape space model. Based on the proposed convex optimization method, 3 D human pose reconstruction by shape space model and 3 D variable shape model was carried out on the mocap database. To improve accuracy and reduce the number of iterations, we use PSO algorithm to optimize initial value of the key parameter. The experimental results show that the improved algorithm exhibits less iterations but higher accuracy, which can be much helpful in practical applications.

关键词： LDD-L1 regularization 3D reconstruction PSO

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Formation Flying Techniques for the Virtual Telescope for X-Ray Observations

arXiv

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arXiv 2020年

作者： Kyle, Rankin Neerav, Shah John, Krizmanic Steven, Stochaj Asal, Naseri Department of Mechanical and Aerospace Engineering New Mexico State University United States Goddard Space Flight Center NASA United States CRESST NASA GSFC University of Maryland Baltimore County United States Klipsch School of Electrical and Computer Engineering New Mexico State University United States Program Manage/Systems Engineer Space Dynamics Laboratory

The Virtual Telescope for X-Ray Observations (VTXO) is an Astrophysics SmallSat mission being developed to demonstrate 10-milliarcsecond X-ray imaging using a Phase Fresnel Lense (PFL)-based space telescope. PFLs promise to provide several orders of magnitude improvement in angular resolution over current state of the art X-ray optics. However, PFLs for astronomical applications requires a very long focal length, for VTXO the focal length is estimated to be in the range of 0.5 km to 4 km. Since these focal lengths are not feasible on a single spacecraft, the proposed solution is to use two separate spacecraft, one with the lense(s), and the second with an X-ray camera. These two spacecrafts will then fly in a formation approximating a single rigid telescope. In order to achieve this configuration, the two spacecraft must maintain the formation a focal length distance apart, with centimeter level control, and sub-millimeter level knowledge requirements. Additionally, for the telescope to achieve sufficient exposure time, the system must keep the telescope axis pointed at a fixed target on the celestial sphere for durations on the order of a few hours. VTXO’s system architecture calls for two CubeSats to operate in a highly eccentric Earth orbit with one of the spacecraft’s traveling on a natural keplarian orbit. The second spacecraft will then fly on a "pseudo" orbit maintaining a fixed offset relative to the celestial sphere during observations. Observations with this system will occur near apogee where differential forces on the spacecrafts are minimal which in turn minimizes fuel consumption. The "pseudo" orbit where the second spacecraft is located is not quite a stable orbit requiring small continuous propulsion to maintain formation. This paper and presentation will overview VTXO’s system architecture, additionally it will look in depth at the formation flying techniques, including fuel consumption, and methods for establishing, and maintaining the formation. B

关键词： Orbits

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Variational Policy Gradient Method for Reinforcement Learning with General Utilities

arXiv

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arXiv 2020年

作者： Zhang, Junyu Koppel, Alec Bedi, Amrit Singh Szepesvari, Csaba Wang, Mengdi Department of Industrial and Systems Engineering University of Minnesota MinneapolisMN55455 United States Computational and Information Sciences Directorate US Army Research Laboratory AdelphiMD20783 United States Department of Computer Science DeepMind University of Alberta PrincetonNJ08544 United States Department of Electrical Engineering Center for Statistics and Machine Learning Princeton University Deepmind PrincetonNJ08544 United States

In recent years, reinforcement learning (RL) systems with general goals beyond a cumulative sum of rewards have gained traction, such as in constrained problems, exploration, and acting upon prior experiences. In this paper, we consider policy optimization in Markov Decision Problems, where the objective is a general concave utility function of the state-action occupancy measure, which subsumes several of the aforementioned examples as special cases. Such generality invalidates the Bellman equation. As this means that dynamic programming no longer works, we focus on direct policy search. Analogously to the Policy Gradient Theorem Sutton et al. (2000) available for RL with cumulative rewards, we derive a new Variational Policy Gradient Theorem for RL with general utilities, which establishes that the parametrized policy gradient may be obtained as the solution of a stochastic saddle point problem involving the Fenchel dual of the utility function. We develop a variational Monte Carlo gradient estimation algorithm to compute the policy gradient based on sample paths. We prove that the variational policy gradient scheme converges globally to the optimal policy for the general objective, though the optimization problem is nonconvex. We also establish its rate of convergence of the order O(1/t) by exploiting the hidden convexity of the problem, and proves that it converges exponentially when the problem admits hidden strong convexity. Our analysis applies to the standard RL problem with cumulative rewards as a special case, in which case our result improves the available convergence rate. Copyright © 2020, The Authors. All rights reserved.

关键词： Dynamic programming

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