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Numerical and analytical approaches to dynamic beam waist optimization for LEO-to-GEO laser communication

OSA CONTINUUM 2020年第12期3卷 3508-3522页

作者： Phong Xuan Do Carrasco-Casado, Alberto Tan Van Vu Hosonuma, Takayuki Toyoshima, Morio Nakasuka, Shinichi Univ Tokyo Dept Aeronaut & Astronaut Tokyo Japan Natl Inst Informat & Commun Technol Space Commun Lab Tokyo Japan Univ Tokyo Grad Sch Informat Sci & Technol Dept Informat & Commun Engn Tokyo Japan

We study a dynamic scheme for optimizing the beam waist in low earth orbit-to-geostationary orbit (LEO-to-GEO) laser communication for small satellites under the influence of the pointing error on the transmitting side. Using the Marcum Q-function, we express the channel gain of the link in a closed form. Based on this expression, we obtain an accurate approximation of the optimal value of the laser beam waist via both numerical and analytical approaches to achieve the minimal average bit error probability (ABEP) of the LEO-to-GEO communication. The analytical approximation has a simple form and can be straightforwardly calculated and employed in practice. We numerically compute the ABEP with our analytical solution and the sub-optimal solution proposed in the literature. The results show a strong agreement between our solution and previous work. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

关键词： computation methods Gaussian beams Laser beams Laser communications Power spectral density Synthetic aperture radar

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Noise-tolerant single-photon imaging with a superconducting nanowire camera

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OPTICS LETTERS 2020年第24期45卷 6732-6735页

作者： Kong, Lingdong Zhao, Qingyuan Zheng, Kai Lu, Haiyangbo Chen, Shi Tao, Xu Wang, Hui Hao, Hao Wan, Chao Tu, Xuecou Zhang, Labao Jia, Xiaoqing Kang, Lin Chen, Jian Wu, Peiheng Nanjing Univ Sch Elect Sci & Engn Res Inst Superconductor Elect RISE Nanjing 210023 Jiangsu Peoples R China Purple Mt Labs Nanjing 211111 Jiangsu Peoples R China

The quality of an image is limited to the signal-to-noise ratio of the output from sensors. As the background noise increases much more than the signal, which can be caused by either a huge attenuation of light pulses after a longhaul transmission or a blinding attack with a strong flood illumination, an imaging system stops working properly. Here we built a superconducting single-photon infrared camera of negligible dark counts and 60 ps timing resolution. Combining with an adaptive 3D slicing algorithm that gives each pixel an optimal temporal window to distinguish clustered signal photons from a uniformly distributed background, we successfully reconstructed. 3D single-photon images at both a low signal level (similar to 1 average photon per pixel) and extremely high noise background (background-to-signal ratio = 200 within a period of 50 ns before denoising). Among all detection events, we were able to remove 99.45% of the noise photons while keeping the signal photon loss at 0.74%. This Letter is a direct outcome of quantum-inspired imaging that asks for a co-development of sensors and computational methods. We envision that the proposed methods can increase the working distance of a long-haul imaging system or defend it from blinding attacks. (C) 2020 Optical Society of America

关键词： Attenuation computation methods Illumination Image quality Stray light Three dimensional imaging

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Performance enhancement of Brillouin sensing systems based on compressive sampling

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OSA CONTINUUM 2020年第11期3卷 3116-3124页

作者： Zhou, Da-Peng Ning, Wankun Shu, Dayong Peng, Wei Chen, Liang Bao, Xiaoyi Dalian Univ Technol Sch Phys Dalian 116024 Liaoning Peoples R China Dalian Univ Technol DUT BSU Joint Inst Dalian 116024 Liaoning Peoples R China Univ Ottawa Dept Phys Ottawa ON K1N 6N5 Canada

Compressive sampling theory asserts that certain signals can be recovered from far fewer samples than traditional methods use. We propose to enhance the performance of Brillouin sensing systems by improving the signal-to-noise ratio of the Brillouin spectra with random undersampled measurements of the original noisy Brillouin spectra. The number of acquisitions can be significantly reduced, and at the same time the measurement accuracy can be improved due to the increased signal-to-noise ratio of recovered Brillouin spectra measured based on compressive sampling principle compared to those measured directly by conventional methods. Experiments show that by performing similar to 30% of the acquisitions that are required by conventional systems, over 7 dB signal-to-noise ratio enhancement can be obtained. Our proposal can be applied to any practical Brillouin sensing system whose performance can be enhanced by taking the advantages of recent advancements in computational methods without costly or sophisticated hardware modifications. (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

关键词： Brillouin optical time domain reflectometry computation methods Frequency measurement Optical fibers Optical sensing Semiconductor optical amplifiers

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CALCULATING THE EXPECTED VALUE OF SAMPLE INFORMATION IN PRACTICE: CONSIDERATIONS FROM THREE CASE STUDIES

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MEDICAL DECISION MAKING 2020年第1期40卷 E337-E338页

作者： Heath, Anna Kunst, Natalia R. Jackson, Christopher Strong, Mark Alarid-Escudero, Fernando Goldhaber-Fiebert, Jeremy D. Baio, Gianluca Menzies, Nicolas A. Jalal, Hawre Hosp Sick Children Toronto ON Canada Univ Oslo Fac Med Dept Hlth Management & Hlth Econ Oslo Norway Univ Cambridge MRC Biostat Unit Cambridge England Univ Sheffield Sch Hlth & Related Res ScHARR Sheffield S Yorkshire England Ctr Res & Teaching Econ Drug Policy Program Aguascalientes AG Mexico Stanford Univ Ctr Hlth Policy & Primary Care & Outcomes Res Stanford Hlth Policy Stanford CA 94305 USA UCL London England Harvard TH Chan Sch Publ Hlth Dept Global Hlth & Populat Boston MA USA Univ Pittsburgh Grad Sch Publ Hlth Pittsburgh PA USA

4K-6

关键词： computation methods expected value of sample information health economic decision modelling study design value of information

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computation method for analysis of sliding faults in power systems

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BULLETIN OF THE POLISH ACADEMY OF SCIENCES-TECHNICAL SCIENCES 2021年第1期69卷

作者： Machowski, Jan Robak, Sylwester Warsaw Univ Technol Fac Elect Engn Elect Power Engn Inst Ul Koszykowa 75 PL-00662 Warsaw Poland

Short-circuit analysis is conducted based on the nodal impedance matrix, which is the inversion of the nodal admittance matrix. If analysis is conducted for sliding faults, then for each fault location four elements of the nodal admittance matrix are subject to changes and the calculation of the admittance matrix inversion needs to be repeated many times. For large-scale networks such an approach is time consuming and unsatisfactory. This paper proves that for each new fault location a new impedance matrix can be found without recalculation of the matrix inversion. It can be found by a simple extension of the initial nodal impedance matrix calculated once for the input model of the network. This paper derives formulas suitable for such an extension and presents a flowchart of the computational method. Numerical tests performed for a test power system confirm the validity and usefulness of the proposed method.

关键词： power system short-circuit analysis sliding faults computation methods

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Review and perspective on bioactive peptides: A roadmap for research, development, and future opportunities

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JOURNAL OF AGRICULTURE AND FOOD RESEARCH 2022年 9卷

作者： Du, Zhenjiao Li, Yonghui Kansas State Univ Dept Grain Sci & Ind Manhattan KS 66506 USA

Bioactive peptides (BPs) possess a broad spectrum of beneficial effects, such as antioxidant, antihypertensive, antidiabetic, anticancer, anti-inflammatory, antimicrobial, and anti-aging functions. Given their rapid developments, it is important to revisit our knowledge of BPs, including their production, bioactivity, bioaccessibility, commercial availability, and the latest work in structural bioinformatics. In this paper, recent advances in BP sources, production and characterization, bioactivities, and commercial availability are briefly reviewed;critical challenges, as well as corresponding perspectives, are highlighted. In silico approaches show a great potential to accelerate BP studies and warrant further research. An integrated and comprehensive workflow for future BP screening and evaluation is proposed. There is a great demand for in vivo experiments to further understand the mechanisms of BPs and promote their commercialization. This perspective paper will be a useful reference for both academic researchers and industry partners to comprehend current developments in BPs and to design future research that connects structural bioinformatics, advanced computation methods, and wet chemistry studies.

关键词： Bioactive peptide Food proteins QSAR Molecular docking Molecular dynamics simulation computation methods Commercial peptides

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computational sensing with a multiplexed vertical flow assay for high-sensitivity C-Reactive protein quantification

Computational sensing with a multiplexed vertical flow assay...

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Conference on Lasers and Electro-Optics (CLEO)

作者： Ballard, Zachary S. Joung, Hyou-Arm Goncharov, Artem Liang, Jesse Nugroho, Karina Di Carlo, Dino Garner, Omai B. Ozcan, Aydogan Univ Calif Los Angeles Dept Elect & Comp Engn Los Angeles CA 90024 USA Univ Calif Los Angeles Calif NanoSyst Inst Los Angeles CA 90024 USA Univ Calif Los Angeles Dept Bioengn Los Angeles CA 90024 USA Univ Calif Los Angeles Dept Pathol & Med Los Angeles CA 90024 USA

We demonstrate computational sensing with a multiplexed paper-based point-of-care assay for high sensitivity C-Reactive protein testing (hsCRP). Using blindly-tested human serum samples, we achieved an R2 value of 0.9... 详细信息

ISBN: (数字)9781943580767

ISBN: (纸本)9781943580767

关键词： Chemical vapor deposition computation methods Image analysis Neural networks Sensor performance Sensors

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Resolution Enhancement in Scanning Electron Microscopy using Deep Learning

Resolution Enhancement in Scanning Electron Microscopy using...

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Conference on Lasers and Electro-Optics (CLEO)

作者： de Haan, Kevin Ballard, Zachary S. Rivenson, Yair Wu, Yichen Ozcan, Aydogan Univ Calif Los Angeles David Geffen Sch Med Elect & Comp Engn Dept Los Angeles CA 90095 USA Univ Calif Los Angeles David Geffen Sch Med Bioengn Dept Los Angeles CA 90095 USA Univ Calif Los Angeles David Geffen Sch Med Calif NanoSyst Inst CNSI Los Angeles CA 90095 USA Univ Calif Los Angeles David Geffen Sch Med Dept Surg Los Angeles CA 90095 USA

We present a deep learning-based framework to perform image super-resolution in scanning electron microscopy. The technique was demonstrated to perform a resolution enhancement using a standard resolution test target ... 详细信息

ISBN: (数字)9781943580767

ISBN: (纸本)9781943580767

关键词： computation methods Electron microscopy Image quality Neural networks Scanning electron microscopy Spatial frequency

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Efficient Automated Nanocavity Optimization by Direct Use of Finite Element Method computation

Efficient Automated Nanocavity Optimization by Direct Use of...

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Conference on Lasers and Electro-Optics (CLEO)

作者： Kuramochi, Eiichi Kita, Shota Shinya, Akihiko Notomi, Masaya NTT Corp NTT Nanophoton Ctr 3-1 Morinosato Wakamiya Atsugi Kanagawa 2430198 Japan NTT Corp NTT Basic Res Labs 3-1 Morinosato Wakamiya Atsugi Kanagawa 2430198 Japan

An automated finite-element-method-based optimization code can optimize the position of more than 20 holes generated in an L3 nanocavity with a theoretical Q factor exceeding 2x10(7) with only 111-sample-cavity genera... 详细信息

ISBN: (数字)9781943580767

ISBN: (纸本)9781943580767

关键词： computation methods Finite element method Nanocavities Neural networks Photonic crystal cavities Q factor

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Feature issue introduction: advanced computational nanophotonics: from materials to devices

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OPTICAL MATERIALS EXPRESS 2019年第4期9卷 1967-1970页

作者： Kildishev, Alexander, V Hu, Juejun Martin, Olivier J. F. Werner, Douglas H. Purdue Univ Birck Nanotechnol Ctr Sch Elect & Comp Engn W Lafayette IN 47907 USA MIT Dept Mat Sci & Engn Cambridge MA 02139 USA Swiss Fed Inst Technol Lausanne EPFL Nanophoton & Metrol Lab CH-1015 Lausanne Switzerland Penn State Univ Dept Elect Engn University Pk PA 16802 USA

computational nanophotonics has already made a disruptive impact on the photonic and optoelectronic industries and has dramatically influenced the ways today's optical engineers create, optimize, and use innovative materials and computer-aided services. This Feature Issue presents a set of eleven papers combined under the joint title of Advanced computational Nanophotonics: From Materials to Devices. The science and art of computational photonics have a long established history, yet interest in new approaches to advanced multiphysics modeling at the nanoscale and hence to innovatory multi-objective optimization techniques for nanophotonics have been growing exponentially in the last decade, and are now the subject of intense cross-disciplinary research efforts. The papers selected for the Feature Issue present a diverse palette of topics that, for example, include a comprehensive review of new optimization techniques, a fundamental theoretical concept of photonic Dirac monopoles, along with new multiphysics approaches to full-wave material modeling in non-linear nanophotonics and, in particular, to innovative modeling of photonic neural networks. Applications of advanced computational methods are additionally showcased with space-time light control by dynamic metasurfaces, polarization control with structured color all-dielectric metafilms, and an optofluidic system driven by a thermoplasmonic element. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

关键词： computation methods Evanescent waves Polarization control Quantum information processing Rigorous coupled wave analysis Total internal reflection

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