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Influences of Al2O3/Nb2O5 co-doping on structural evolution and dielectric properties of Zn0.5Ti0.5-x(Al0.75Nb0.35)xNbO4 (0 ≤ x ≤ 0.3) ceramics

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IOP Conference Series: Materials science and Engineering 2019年第1期479卷

作者： H Y Yang S R Zhang H C Yang Y Yuan E Z Li National Engineering Research Center of Electromagnetic Radiation Control Materials University of Electronic Science and Technology of China Chengdu China Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of China Chengdu China Institute of Electronic and Information Engineering of UESTC in Guangdong Dongguan 523808 People's Republic of China China

In present study, the influences of Al2O3 and Nb2O5 co-doping for Ti site on structure and microwave dielectric performances of Zn0.5Ti0.5-x (Al0.75Nb0.35) x NbO4 ceramics were discussed. Pure ixiolite-structured Zn0.5Ti0.5NbO4 solid solution is prepared when x ≤ 0.15. Phase transformation takes place at 0.2 ≤ x ≤ 0.3, where columbite ZnNb2O6 phase exists. The dielectric constant (r) of ceramics presents a decline trend, which is attributed to the decrease of dielectric polarizability (0 ≤ x ≤ 0.15) and the formation of ZnNb2O6 phase (0.2 ≤ x ≤ 0.3). The quality factor (Q × f), however, decrease till x = 0.15 and increase after that. The temperature coefficient of resonant frequency (τf) value varies consistently with the densification. Typical dielectric ceramics (x = 0.3) was synthesized at 115°C: a r of 25.79, a Q × f about 56114 GHz and a τf of -78.18 ppm/°C, were obtained.

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A linearized photonic sampling structure by using polarization-dependent modulators in sagnac loop

A linearized photonic sampling structure by using polarizati...

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International Topical Meeting on Microwave Photonics (MWP)

作者： Dong Liang Yong Liu Xiaojun Li Qinggui Tan Wei Jiang National Key Laboratory of Science and Technology on Space Microwave Xian Shaanxi China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu China

In this paper, a new photonic sampling structure with effective nonlinearity suppression and good signal-to-noise ratio (SNR) performance is proposed. The key feature of this scheme is the polarization-dependent modulators (P-DMZMs) and the sagnac loop structure. Attributing to the polarization sensitive characteristic of P-DMZMs, differences between transfer functions of the fundamental signals and distortions become visible. Meanwhile, the selection of specific biases in P-DMZMs provides the possibility of a preferable linearized performance for real-time photonic sampling. Simulation results indicate that the proposed scheme is capable for effective nonlinearity suppression and provides good SNR performance even in a large frequency range.

关键词： Modulation Signal to noise ratio Photonics Sagnac interferometers Space technology Microwave technology

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2D Structured Turbo Compressed Sensing for Channel Estimation in OTFS Systems

2D Structured Turbo Compressed Sensing for Channel Estimatio...

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International Conference on Communication Systems

作者： Mingchen Zhang Fanggang Wang Xiaojun Yuan Lei Chen Center for Intelligent Networking and Commun National Key Lab. of Sci. and Tech. on Commun University of Electronic Sci. and Tech. of China Chengdu China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China School of Information Science and Technology ShanghaiTech University Shanghai China

ISBN: (纸本)9781538678657;9781538678640

High-speed mobility is a challenging scenario in wireless communications since it involves fast-varying channels, in which orthogonal frequency-division multiplexing (OFDM) could degrade significantly without accurate Doppler compensation. Recently, a modulation called orthogonal time frequency space (OTFS) was proposed for the specific scenario. The advantages are two-fold, i.e., the orthogonality in the time-frequency domain and the clustered sparsity of channel information in the delay-Doppler domain. In this paper, we propose a two-dimensional structured Turbo compressed sensing (CS) algorithm based on our previous work on Turbo CS for fast time-varying channel estimation. Markov random field is applied to model the clustered sparse prior of the channel in the two-dimensional delay-Doppler domain. In contrast to the conventional Turbo CS, a two-dimensional structured minimum mean-square error (MMSE) estimator is designed by message passing over a Markov random field. The convergence and the MSE performance of the proposed algorithm is evaluated, and the simulation results validate that the proposed algorithm outperforms the existing algorithms.

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Accurate spectral super-resolution from single RGB image using multi-scale CNN

arXiv

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arXiv 2018年

作者： Yan, Yiqi Zhang, Lei Li, Jun Zhang, Yanning Wei, Wei School of Electronics and Information Northwestern Polytechnical University Xi'an China School of Computer Science Northwestern Polytechnical University Xi'an China National Engineering Laboratory for Integrated Aero-Space-Ground-Ocean Big Data Application Technology China Guangdong Provincial Key Laboratory of Urbanization and Geo-simulation School of Geography and Planning Sun Yat-Sen University Guangzhou China

Different from traditional hyperspectral super-resolution ap-proaches that focus on improving the spatial resolution, spectral super-resolution aims at producing a high-resolution hyperspectral image from the RGB observation with super-resolution in spectral domain. However, it is challenging to accurately reconstruct a high-dimensional continuous spectrum from three discrete intensity values at each pixel, since too much information is lost during the procedure where the latent hyper-spectral image is downsampled (e.g., with ×10 scaling factor) in spectral domain to produce an RGB observation. To address this problem, we present a multi-scale deep convolutional neural network (CNN) to ex-plicitly map the input RGB image into a hyperspectral image. Through symmetrically downsampling and upsampling the intermediate feature maps in a cascading paradigm, the local and non-local image informa-tion can be jointly encoded for spectral representation, ultimately im-proving the spectral reconstruction accuracy. Extensive experiments on a large hyperspectral dataset demonstrate the effectiveness of the pro-posed method. Copyright © 2018, The Authors. All rights reserved.

关键词： Optical resolving power

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Hydrolysis of polyaluminum chloride prior to coagulation:Effects on coagulation behavior and implications for improving coagulation performance

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Journal of Environmental sciences 2017年第7期29卷 162-169页

作者： Zhongguo Zhang Jun Wang Dan Liu Jiuyi Li Xiaolin Wang Boyu Song Bing Yue Kehui Zhao Yun Song Key Laboratory of Energy-Water Conservation and Wastewater Resources Recovery(Environmental Protection Research Institute of Light Industry) China National Light IndustryBeijing 100089China University of Chinese Academy of Sciences Beijing 100049China Beijing Key Laboratory of Industrial Wastewater Treatment and Resource Recovery Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Civil and Environmental Engineering Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality SafeguardSchool of Civil EngineeringBeijingJiaotong UniversityBeijing 100044China Beijing Water Authority Beijing 100038China Beijing Key Laboratory of Industrial Land Contamination and Remediation Environmental Protection Research Institute of Light IndustryBeijing Academy of Science and TechnologyBeijing 100089China

The effects of polyaluminum chloride（PACl） hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the ＂reversed coagulation test＂.The tests showed that PACl hydrolysis prior to coagulation decreased the performance of charge neutralization coagulation in the case of short-time slow mixing（10 min;G = 15 sec-1） and increased the optimal dosage for charge neutralization and sweep ***,the hydrolysis time had insignificant effects on the size and zeta potential of PACl precipitates and the residual turbidity of the raw ***,PACl hydrolysis prior to coagulation and the size of PACl precipitates had a negligible effect on the performance of sweep *** results imply that,in practice,preparing a PACl solution with deionized water,rather than tap water or the outlet water from a wastewater treatment unit,can significantly save PACl consumption and improve the performance of charge neutralization coagulation,while preparing the PACl solution with tap or outlet water would not affect the performance of sweep *** addition,the optimal rapid mixing intensity appears to be determined by a balance between the degree of coagulant hydrolysis before contacting the primary particles and the average size of flocs in the rapid mixing *** results provide new insights into the role of PACl hydrolysis and will be useful for improving coagulation efficiency.

关键词： Polyaluminum chloride（PACl） Precipitate Hydrolysis Charge neutralization Sweep coagulation

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Author Correction: Repeated dose multi-drug testing using a microfluidic chip-based coculture of human liver and kidney proximal tubules equivalents

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Scientific reports 2020年第1期10卷 17018页

作者： Ni Lin Xiaobing Zhou Xingchao Geng Christopher Drewell Juliane Hübner Zuogang Li Yingli Zhang Ming Xue Uwe Marx Bo Li Key Laboratory of Beijing for Safety Evaluation of Drugs National Center for Safety Evaluation of Drugs National Institutes for Food and Drug Control A8 Hongda Middle Street Beijing Economic-Technological Development Area Beijing 100176 P. R. China. Department of Pharmacology Beijing Laboratory for Biomedical Detection Technology and Instrument School of Basic Medical Sciences Capital Medical University Beijing 100069 China. Beijing Institute for Drug Control 25 Science Park Road Changping District Beijing 102206 China. Technische Universitaet Berlin Institute of Biotechnology Department Medical Biotechnology Gustav-Meyer-Allee 25 13355 Berlin Germany. Department of Pharmacology Beijing Laboratory for Biomedical Detection Technology and Instrument School of Basic Medical Sciences Capital Medical University Beijing 100069 China. xuem@***. TissUse GmbH Oudenarder Strasse 16 13347 Berlin Germany. uwe.marx@***. National Institutes for Food and Drug Control 31 HuaTuoroad Daxing district Beijing 102629 China. libo@***.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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River Water Quality and its Relation with Air Quality: A Long-Term Case Study in a Remote and Pristine NW Italian Headwater Catchment

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环境核算与管理（英文） 2017年第1期5卷 35-47页

作者： Marco Casazza Franca Maraga Gengyuan Liu Massimiliano Lega Laura Turconi Sergio Ulgiati Department of Science and Technology University of Naples'Parthenope' Naples 81043 Italy National Research Council Department of Earth and Environment Research Institute for geo-hydrological protection (CNR-IRPI) Unit of Turin Italy State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Beijing Engineering Research Center for Watershed Environmental Restoration & Integrated Ecological Regulation Beijing 100875 China Department of Science and Technology University of Naples'Parthenope' Naples 81043 Italy State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Beijing Engineering Research Center for Watershed Environmental Restoration & Integrated Ecological Regulation Beijing 100875 China

This paper analyses the water quality characteristics of a remote and pristine basin,the Gallina small catchment,located in the Piemonte Region (NW Italy).In particular,the ion content of river water and precipitation are assessed for two distinct periods (October-December of years 1992 and 2011).These time frames are characterized by a change of air quality management rules for the study area which came into force after year ***,late Autunm months,which are considered in this study,are characterized by a peak of recorded precipitations in the area under ***,this is a period of the year where atmospheric emission intensity and distribution are greater with respect to Spring and *** chemical nature of the monitored water body was assessed through the use of Piper *** found evidence of erosional processes,which chemically altered the water compared to the quality of *** signature of air chemistry was also evident,through a shift to less sulphate,after the change of air quality regulations introduced in year *** presence of marine ions,in case of major weather perturbations,typical of the late Autumn in the monitored area,was *** fact was particularly evident for the month of November 2011,in association to a major flooding event occurred in the Piemonte *** presence of a minor ionic component,associated to rainfall waters,depending upon soil particle resuspension and transport was also ***,the prevailing origin of the measured ions was *** results show the importance of improved management actions,which should be taken in order to further reduce the trans-boundary atmospheric pollution,which constitutes a threat to water quality and a further element of indirect water pollution transfer across different areas.

关键词： Water quality Atmospheric deposition Air quality Pristine basin

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Realization of artificial neuron based on threshold switching memristor

Realization of artificial neuron based on threshold switchin...

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Information Storage System and technology, ISST 2017

作者： Zhang, Xumeng Wang, Wei Zhao, Xiaolong Lv, Hangbing Long, Shibing Liu, Qi Liu, Ming Key Laboratory of Microelectronics Devices and Integrated Technology Institute of Microelectronics of Chinese Academy of Sciences Beijing100029 China University of Chinese Academy of Sciences Beijing100049 China College of Electronic Science and Engineering National University of Defense Technology Changsha410073 China Department of Physics Hubei Nuclear Solid Physics Key Laboratory and Center for Ion Beam Application Wuhan University Wuhan430072 China

ISBN: (纸本)9781943580378

Neuron and synapse are the basic constitutional units of biological neural network which has high efficiency in information processing. On account of which, the bio-inspired neuromorphic computing has attracted considerable attention. In this letter, we demonstrate an integration and fire artificial neuron (neuristor) based on threshold switching memristor. The neuristor captures 4 crucial features for actionpotential- based computing: all-or-nothing spiking of an action potential, threshold-driven spiking, a refractory period, and the strength-modulated frequency response. A system-level simulation of the neuristor as post-synaptic neuron show that the validity to be used for a pattern recognition application. The experimental and simulation result exhibit that the neurisor can implement the basic functions of spiking neurons and has a great potential for neuromorphic computing. © 2017 OSA.

关键词： Memristors

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All-sky search for long-duration gravitational-wave bursts in the third Advanced LIGO and Advanced Virgo run

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Physical Review D 2021年第10期104卷 102001-102001页

作者： R. Abbott T. D. Abbott F. Acernese K. Ackley C. Adams N. Adhikari R. X. Adhikari V. B. Adya C. Affeldt D. Agarwal M. Agathos K. Agatsuma N. Aggarwal O. D. Aguiar L. Aiello A. Ain P. Ajith T. Akutsu S. Albanesi A. Allocca P. A. Altin A. Amato C. Anand S. Anand A. Ananyeva S. B. Anderson W. G. Anderson M. Ando T. Andrade N. Andres T. Andrić S. V. Angelova S. Ansoldi J. M. Antelis S. Antier S. Appert Koji Arai Koya Arai Y. Arai S. Araki A. Araya M. C. Araya J. S. Areeda M. Arène N. Aritomi N. Arnaud S. M. Aronson K. G. Arun H. Asada Y. Asali G. Ashton Y. Aso M. Assiduo S. M. Aston P. Astone F. Aubin C. Austin S. Babak F. Badaracco M. K. M. Bader C. Badger S. Bae Y. Bae A. M. Baer S. Bagnasco Y. Bai L. Baiotti J. Baird R. Bajpai M. Ball G. Ballardin S. W. Ballmer A. Balsamo G. Baltus S. Banagiri D. Bankar J. C. Barayoga C. Barbieri B. C. Barish D. Barker P. Barneo F. Barone B. Barr L. Barsotti M. Barsuglia D. Barta J. Bartlett M. A. Barton I. Bartos R. Bassiri A. Basti M. Bawaj J. C. Bayley A. C. Baylor M. Bazzan B. Bécsy V. M. Bedakihale M. Bejger I. Belahcene V. Benedetto D. Beniwal T. F. Bennett J. D. Bentley M. BenYaala F. Bergamin B. K. Berger S. Bernuzzi D. Bersanetti A. Bertolini J. Betzwieser D. Beveridge R. Bhandare U. Bhardwaj D. Bhattacharjee S. Bhaumik I. A. Bilenko G. Billingsley S. Bini R. Birney O. Birnholtz S. Biscans M. Bischi S. Biscoveanu A. Bisht B. Biswas M. Bitossi M.-A. Bizouard J. K. Blackburn C. D. Blair D. G. Blair R. M. Blair F. Bobba N. Bode M. Boer G. Bogaert M. Boldrini L. D. Bonavena F. Bondu E. Bonilla R. Bonnand P. Booker B. A. Boom R. Bork V. Boschi N. Bose S. Bose V. Bossilkov V. Boudart Y. Bouffanais A. Bozzi C. Bradaschia P. R. Brady A. Bramley A. Branch M. Branchesi J. E. Brau M. Breschi T. Briant J. H. Briggs A. Brillet M. Brinkmann P. Brockill A. F. Brooks J. Brooks D. D. Brown S. Brunett G. Bruno R. Bruntz J. Bryant T. Bulik H. J. Bulten A. Buonanno R. Buscicchio D. Buskulic C. Buy R. L. Byer L. Cadonati G. Cagnoli C. Cahillane J. Calderón Bustillo J. D. Callaghan T. A. Callis LIGO Laboratory California Institute of Technology Pasadena California 91125 USA Louisiana State University Baton Rouge Louisiana 70803 USA Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy OzGrav School of Physics and Astronomy Monash University Clayton 3800 Victoria Australia LIGO Livingston Observatory Livingston Louisiana 70754 USA University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201 USA OzGrav Australian National University Canberra Australian Capital Territory 0200 Australia Max Planck Institute for Gravitational Physics (Albert Einstein Institute) D-30167 Hannover Germany Leibniz Universität Hannover D-30167 Hannover Germany Inter-University Centre for Astronomy and Astrophysics Pune 411007 India University of Cambridge Cambridge CB2 1TN United Kingdom Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany University of Birmingham Birmingham B15 2TT United Kingdom Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA) Northwestern University Evanston Illinois 60208 USA Instituto Nacional de Pesquisas Espaciais 12227-010 São José dos Campos São Paulo Brazil Gravity Exploration Institute Cardiff University Cardiff CF24 3AA United Kingdom INFN Sezione di Pisa I-56127 Pisa Italy International Centre for Theoretical Sciences Tata Institute of Fundamental Research Bengaluru 560089 India Gravitational Wave Science Project National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan Advanced Technology Center National Astronomical Observatory of Japan (NAOJ) Mitaka City Tokyo 181-8588 Japan INFN Sezione di Torino I-10125 Torino Italy Università di Napoli “Federico II ” Complesso Universitario di Monte S. Angelo I-80126 Napoli Italy Université de Lyon Université Claude Bernard Lyon 1 CNRS Institut Lumière Matière F-69622 Villeurbanne France

After the detection of gravitational waves from compact binary coalescences, the search for transient gravitational-wave signals with less well-defined waveforms for which matched filtering is not well suited is one of the frontiers for gravitational-wave astronomy. Broadly classified into “short” ≲1 s and “long” ≳1 s duration signals, these signals are expected from a variety of astrophysical processes, including non-axisymmetric deformations in magnetars or eccentric binary black hole coalescences. In this work, we present a search for long-duration gravitational-wave transients from Advanced LIGO and Advanced Virgo’s third observing run from April 2019 to March 2020. For this search, we use minimal assumptions for the sky location, event time, waveform morphology, and duration of the source. The search covers the range of 2–500 s in duration and a frequency band of 24–2048 Hz. We find no significant triggers within this parameter space; we report sensitivity limits on the signal strength of gravitational waves characterized by the root-sum-square amplitude hrss as a function of waveform morphology. These hrss limits improve upon the results from the second observing run by an average factor of 1.8.

关键词： Astrophysical studies of gravity Gravitational wave detection Gravitational wave sources Gravitational waves

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Measurement technology of RF interference current in high current system

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AIP Conference Proceedings 2018年第1期1971卷

作者： Zhihua Zhao Jianxuan Li Xiangming Zhang Lei Zhang National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

Current probe is a detection method commonly used in electromagnetic compatibility. With the development of power electronics technology, the power level of power conversion devices is constantly increasing, and the power current of the electric energy conversion device in the electromagnetic launch system can reach 10kA. Current probe conventionally used in EMC (electromagnetic compatibility) detection cannot meet the test requirements on high current system due to the magnetic saturation problem. The conventional high current sensor is also not suitable for the RF (Radio Frequency) interference current measurement in high current power device due to the high noise level in the output of active amplifier. In this paper, a passive flexible current probe based on Rogowski coil and matching resistance is proposed that can withstand high current and has low noise level, to solve the measurement problems of interference current in high current power converter. And both differential mode and common mode current detection can be easily carried out with the proposed probe because of the probe’s flexible structure.

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