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微波学报 2020年第3期36卷 76-80页

作者：马跃王建朋南京理工大学电光学院南京210094 南京电子器件研究所南京210016

采用内匹配技术,使用两枚GaN HEMT晶体管,在X波段8.0~8.5 GHz频段内,设计并实现了一种高可靠性、高功率附加效率的功率放大器。基于南京电子器件研究所提供的晶体管及负载牵引数据,并结合"L-C-L"匹配网络以及威尔金森功率分配... 详细信息

采用内匹配技术,使用两枚GaN HEMT晶体管,在X波段8.0~8.5 GHz频段内,设计并实现了一种高可靠性、高功率附加效率的功率放大器。基于南京电子器件研究所提供的晶体管及负载牵引数据,并结合"L-C-L"匹配网络以及威尔金森功率分配/合成器,对晶体管的输入和输出阻抗进行了相应匹配,使得其端口阻抗均为50Ω。最终通过两胞合成的方式实现了在目标频段内,栅电压-2.2 v、漏电压24 v,连续波工作状态下,所设计功率放大器输出功率高于20 W、功率增益大于10 dB、功率的附加效率大于49.7%。其中,在8.1~8.4 GHz,该功率放大器功率附加效率超过52%,优于我国现有相近频段内匹配功率放大器的功率附加效率,并通过实验验证了该设计方案的可靠性。

关键词：氮化镓高电子迁移率晶体管(GaN HEMT) 功率放大器 X波段内匹配高功率附加效率

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Double-folded catadioptric lens for smartphone portraiture photography 7

Double-folded catadioptric lens for smartphone portraiture p...

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Conference on optical design and engineering vII

作者： Sheil, Conor J. Goncharov, Alexander v. Natl Univ Ireland Sch Phys Appl Opt Grp Galway Ireland

ISBN: (数字)9781510619180

ISBN: (纸本)9781510619180

Smartphones are increasingly utilising a dual-camera setup, introducing the possible use of one or more specialised camera modules. The current work presents a smartphone camera designed for portraiture. In portraiture, it is desirable to have a natural Bokeh effect, resulting from shallow depth of field (DoF). Because DoF is inversely related to the square of diameter, the proposed lens has a large entrance pupil diameter and low F-number. To fit such a camera within typical smartphone housing, the design is doubly folded, resulting in a compact z-profile (phone thickness) of less than 5 mm, with a total ray path of 13 mm. Due to physical limitations, the field-of-view (Fov) is reduced;this is acceptable, considering the specialised application of the camera and attractively large entrance pupil diameter. With a focal length of 7.6 mm, the system is retrofocus, but could be considered telephoto in terms of its z-height, when compared to typical smartphone lenses. This proof-of-concept design is demonstrated here using glasses. Axial colour is controlled using two doublets. For compactness, the aperture stop is positioned between the first doublet and first fold mirror, also allowing balancing of lateral colour and distortion. For very compact applications, a fixed-focus version of this system was designed. However, considering the large focal length and diameter, the hyperfocal distance is unattractively large;hence, a slightly longer refocussing system was also designed. Refocus is achieved by moving the the second doublet, the power of which must be increased relative to the fixed-focus design-the power increase disturbs the aberration balance about the stop, and hence lateral colour and distortion increase slightly. Distortion remains below 5% and lateral colour should be possible to correct digitally.

关键词： Portraiture catadioptric smartphone optics folded optics depth of field aspherics

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Analysing the level of academic writing literacy of tusur graduate students

Analysing the level of academic writing literacy of tusur gr...

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2019 International Multi-Conference on engineering, Computer and Information Sciences, SIBIRCON 2019

作者： Shpit, Elena I. Sobolevskaya, Olga v. Dept. of Foreign Languages Tomsk Russia

ISBN: (纸本)9781728144016

The intensification of research at Tomsk State University of Control Systems and Radioelectronics (TUSUR) leads to the increase of publication activity of graduate students. However, numerous language and style problems in their research articles in English indicate the lack of academic writing literacy, which impedes the effective publication process. Up to date, there has been no specialized course for teaching English for Academic Purposes in TUSUR. The aim of this study is to analyze the current level of paper writing skills of TUSUR first-year graduate students and their motivation for studying EAP introduced into the curriculum according to the new educational standard. The authors conducted a questionnaire survey covering most common grammar, vocabulary, punctuation and genre mistakes from students' writings. The questionnaire analysis described in the paper outlines the extent of the problem and allows defining the range and profile of didactic units for an elective EAP course. We expect that the introduction of such course will lead to the increase of publication activity of young scientists. © 2019 IEEE.

关键词： Teaching

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基于DvD光学读取头的悬臂式低频加速度计

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机械工程学报 2019年第2期55卷 10-17页

作者：李瑞君常振鑫雷英俊胡鹏浩范光照合肥工业大学仪器科学与光电工程学院合肥230009 大连理工大学机械工程学院大连116024

低频振动对高精度加工和测量都有严重不利影响,被动隔振方法无法有效减小低频振动,精确测量低频振动是主动隔振的前提。研制了一种基于DvD光学读取头的悬臂式低频加速度计。介绍了低频加速度计的检测原理和结构;将市售DvD光学读数头改... 详细信息

低频振动对高精度加工和测量都有严重不利影响,被动隔振方法无法有效减小低频振动,精确测量低频振动是主动隔振的前提。研制了一种基于DvD光学读取头的悬臂式低频加速度计。介绍了低频加速度计的检测原理和结构;将市售DvD光学读数头改装成了高精度位移传感器;在分析和反复优化的基础上确定了悬臂梁式弹簧片合适的材料和结构参数。以自制振动台为振源,高精度低漂移的电涡流传感器(分辨率0.07nm)作为基准,对所研制的加速度计进行了标定,结果为灵敏度9.26 v/g,频率响应范围3～10 Hz,加速度测量范围0.4～32.8 mg,10次测量标准差优于0.01 mg,共振频率44 Hz。可以用于低频微小振动的检测。

关键词：微振动低频悬臂梁 DvD光学读取头加速度计

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Cryogenic Detector Preamplifer developments at the ANU 8

Cryogenic Detector Preamplifer Developments at the ANU

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Conference on High Energy, optical, and Infrared Detectors for Astronomy vIII

作者： vaccarella, Annino Sharp, Robert Ellis, Michael Bouchez, Antonin Conan, Rodolphe Boz, R. Bundy, David Gausachs, Gaston Gilbert, James Gers, Luke Hart, John Herrald, Nick Ireland, Michael Nielsen, Jon Price, Ian vest, Colin Zovaro, Henry Australian Natl Univ Mt Stromlo Observ Weston ACT 2611 Australia BGMTO Corp 465 N Halstead StSuite 250 Pasadena CA 91107 USA

ISBN: (数字)9781510619722

ISBN: (纸本)9781510619722

We present a summary of the cryogenic detector preamplifier development programme under way at the ANU. Cryogenic preamplifiers have been demonstrated for both near-infrared detectors (Teledyne H1RG and Leonardo SAPHIRA eAPD as part of development for the GMTIFS instrument) and optical CCDs (e2v CCD231-84 for use with the AAT/veloce spectrograph). This approach to detector signal conditioning allows low-noise instrument amplifiers to be placed very close to an infra-red detector or optical CCD, isolating the readout path from external interference noise sources. Laboratory results demonstrate effective isolation of the readout path from external interference noise sources. Recent progress has focussed on the first on-sky deployment of four cryogenic preamp channels for the veloce Rosso precision radial velocity spectrograph. We also outline future evolution of the current design, allowing higher speeds and further enhanced performance for the demanding applications required for the on instrument wavefront sensor on the Giant Magellan Integral Field Spectrograph (GMTIFS).

关键词： Cryogenic preamplifier near-infrared lucky imaging CCD

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The wavelength-shifting optical module for the IceCube Upgrade

arXiv

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arXiv 2021年

作者： Rack-Helleis, John Pollmann, Anna Rongen, Martin Abbasi, R. Ackermann, M. Adams, J. Aguilar, J.A. Ahlers, M. Ahrens, M. Alispach, C. Alves, A.A. Amin, N.M. An, R. Andeen, K. Anderson, T. Anton, G. Argüelles, C. Ashida, Y. Axani, S. Bai, X. Balagopal v., A. Barbano, A. Barwick, S.W. Bastian, B. Basu, v. Baur, S. Bay, R. Beatty, J.J. Becker, K.-H. Becker Tjus, J. Bellenghi, C. BenZvi, S. Berley, D. Bernardini, E. Besson, D.Z. Binder, G. Bindig, D. Blaufuss, E. Blot, S. Boddenberg, M. Bontempo, F. Borowka, J. Böser, S. Botner, O. Böttcher, J. Bourbeau, E. Bradascio, F. Braun, J. Bron, S. Brostean-Kaiser, J. Browne, S. Burgman, A. Burley, R.T. Busse, R.S. Campana, M.A. Carnie-Bronca, E.G. Chen, C. Chirkin, D. Choi, K. Clark, B.A. Clark, K. Classen, L. Coleman, A. Collin, G.H. Conrad, J.M. Coppin, P. Correa, P. Cowen, D.F. Cross, R. Dappen, C. Dave, P. de Clercq, C. DeLaunay, J.J. Dembinski, H. Deoskar, K. de Ridder, S. Desai, A. Desiati, P. de vries, K.D. de Wasseige, G. de With, M. DeYoung, T. Dharani, S. Diaz, A. Díaz-vélez, J.C. Dittmer, M. Dujmovic, H. Dunkman, M. Duvernois, M.A. Dvorak, E. Ehrhardt, T. Eller, P. Engel, R. Erpenbeck, H. Evans, J. Evenson, P.A. Fan, K.L. Fazely, A.R. Fiedlschuster, S. Fienberg, A.T. Filimonov, K. Finley, C. Fischer, L. Fox, D. Franckowiak, A. Friedman, E. Fritz, A. Fürst, P. Gaisser, T.K. Gallagher, J. Ganster, E. Garcia, A. Garrappa, S. Gerhardt, L. Ghadimi, A. Glaser, C. Glauch, T. Glüsenkamp, T. Goldschmidt, A. Gonzalez, J.G. Goswami, S. Grant, D. Grégoire, T. Griswold, S. Gündüz, M. Günther, C. Haack, C. Hallgren, A. Halliday, R. Halve, L. Halzen, F. Ha Minh, M. Hanson, K. Hardin, J. Harnisch, A.A. Haungs, A. Hauser, S. Hebecker, D. Helbing, K. Henningsen, F. Hettinger, E.C. Hickford, S. Hignight, J. Hill, C. Hill, G.C. Hoffman, K.D. Hoffmann, R. Hoinka, T. Hokanson-Fasig, B. Hoshina, K. Huang, F. Huber, M. Huber, T. Hultqvist, K. Hünnefeld, M. Institute for Physics JGU Mainz MainzD-55122 Germany Department of Physics Bergische Universität Wuppertal Gaußstraße 20 Wuppertal Germany III. Physikalisches Institut RWTH Aachen University AachenD-52056 Germany Department of Physics University of Adelaide Adelaide5005 Australia Dept. of Physics and Astronomy University of Alaska Anchorage 3211 Providence Dr. AnchorageAK99508 United States Dept. of Physics University of Texas at Arlington 502 Yates St. Science Hall Rm 108 Box 19059 ArlingtonTX76019 United States CTSPS Clark-Atlanta University AtlantaGA30314 United States School of Physics and Center for Relativistic Astrophysics Georgia Institute of Technology AtlantaGA30332 United States Dept. of Physics Southern University Baton RougeLA70813 United States Dept. of Physics University of California BerkeleyCA94720 United States Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Institut für Physik Humboldt-Universität zu Berlin BerlinD-12489 Germany Fakultät für Physik & Astronomie Ruhr-Universität Bochum BochumD-44780 Germany Université Libre de Bruxelles Science Faculty CP230 BrusselsB-1050 Belgium Dienst ELEM BrusselsB-1050 Belgium Department of Physics and Laboratory for Particle Physics and Cosmology Harvard University CambridgeMA02138 United States Dept. of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Dept. of Physics and Institute for Global Prominent Research Chiba University Chiba263-8522 Japan Department of Physics Loyola University Chicago ChicagoIL60660 United States Dept. of Physics and Astronomy University of Canterbury Private Bag 4800 Christchurch New Zealand Dept. of Physics University of Maryland College ParkMD20742 United States Dept. of Astronomy Ohio State University ColumbusOH43210 United States Dept. of Physics and Center for Cosmology and Astro-Particle Physics Ohio State University ColumbusOH43210 United States Niels Bohr Institute

The Wavelength-shifting optical Module (WOM) is a novel optical sensor that uses wavelength shifting and light guiding to substantially enhance the photosensitive area of Uv optical modules. It has been designed for the IceCube Upgrade, a seven-string extension of the IceCube detector planned for the 2022/2023 South Pole deployment season. The WOM consists of a hollow quartz cylinder coated in wavelength shifting paint which serves as detection area and has two photomultipliers (PMTs) attached to the end faces. The light-collecting tube increases the effective photocathode area of the PMTs without producing additional dark current, making it suitable for low-signal, low-noise applications. We report on the design and performance of the WOM with a focus on the 12 modules in production for deployment in the IceCube Upgrade. While the WOM will be deployed in IceCube, its design is applicable to any large-volume particle detector based on the detection of Cherenkov light. Copyright © 2021, The Authors. All rights reserved.

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Modular and scalable control and data acquisition system for power hardware in the loop (PHIL) amplifiers

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JOURNAL OF engineering-JOE 2019年第17期2019卷 3655-3659页

作者： Broadmeadow, Mark A. H. Walker, Geoffrey R. Ledwich, Gerard F. Queensland Univ Technol Sci & Engn Fac Sch Elect Engn & Comp Sci Brisbane Qld Australia

This study presents a newly developed modular system for control of power electronic amplifiers in high-power, high-frequency power hardware in the loop experiments. The proposed design comprises computational nodes connected via multi-gigabit fibre-optic links. Nodes are modular and reconfigurable, allowing interfacing with a range of sensors and actuators, typically voltage and current sensors, and switching converters. The system has been designed for scalability to permit arbitrarily high power ratings and fidelity to be achieved through paralleling and interleaving of multiple power converter modules, targeting an ultimate sample and control rate of 1MHz. Experimental validation is presented using a two-node configuration to facilitate a power electronic experiment operating at 120v(rms) and 10A(rms), with a fundamental frequency of 50Hz and frequency content up to the 11th harmonic.

关键词： switching convertors power electronics optical fibre networks data acquisition power convertors frequency 50 0 Hz frequency 1 0 MHz multiple power converter modules fidelity high-power ratings scalability switching converters current sensors actuators multigigabit fibre-optic links computational nodes loop experiments high-frequency power hardware power electronic amplifiers newly developed modular system PHIL loop amplifiers data acquisition system scalable control frequency content fundamental frequency power electronic experiment two-node configuration

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Cyber security standards and issues in v2X communications for internet of vehicles

Cyber security standards and issues in V2X communications fo...

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Living in the Internet of Things: Cybersecurity of the IoT - 2018

作者： Ivanov, I. Maple, C. Watson, T. Lee, S. WMG Warwick University United Kingdom Electronics and Telecommunication Research Institute Korea Republic of

ISBN: (纸本)9781785617911

Significant developments have taken place over the past few years in the area of vehicular communication systems in the ITS environment. It is vital that, in these environments, security is considered in design and implementation since compromised vulnerabilities in one vehicle can be propagated to other vehicles, especially given that v2X communication is through an ad-hoc type network. Recently, many standardisation organisations have been working on creating international standards related to vehicular communication security and the so-called Internet of vehicles (Iov). This paper presents a discussion of current v2X communications cyber security issues and standardisation approaches being considered by standardisation bodies such as the ISO, the ITU, the IEEE, and the ETSI. © 2018 Institution of engineering and Technology. All rights reserved.

关键词： vehicles

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Growth and optical characterization of 7.5 μm quantum-cascade laser heterostructures grown by MBE 5

Growth and optical characterization of 7.5 μm quantum-casca...

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5th International School and Conference on Optoelectronics, Photonics, engineering and Nanostructures, Saint Petersburg OPEN 2018

作者： Babichev, A.v. Gladyshev, A.G. Kolodeznyi, E.S. Kurochkin, A.S. Sokolovskii, G.S. Bougrov, v.E. Karachinsky, L Ya Novikov, I.I. Dudelev, v.v. Nevedomsky, v.N. Slipchenko, S.O. Lutetskiy, A.v. Sofronov, A.N. Firsov, D.A. vorobjev, L.E. Pikhtin, N.A. Egorov, A Yu ITMO University Saint-Petersburg197101 Russia Connector Optics LLC St-Petersburg194292 Russia Ioffe Institute St-Petersburg194021 Russia Peter the Great St. Petersburg Polytechnic University St-Petersburg195251 Russia

We present the results on growth, characterization and optical properties of quantum-cascade laser heterostructures grown by molecular-beam epitaxy. The double-phonon resonance design for forming of active region together with thick InP-based top cladding was used to increase the quantum-cascade laser performance. The results of electroluminescence studies of 4-cleaved samples are presented. The room temperature lasing at 8.0 um with threshold current density about 1.98 kA/cm2 was achieved. © 2018 Institute of Physics Publishing. All rights reserved.

关键词： Quantum cascade lasers

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Development of surgical binoculars on the basis of polymeric lenses 18

Development of surgical binoculars on the basis of polymeric...

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Conference on current developments in Lens design and optical engineering XvIII

作者： voznesenskaya, Anna Andreev, Lev Ekimenkova, Alisa ITMO Univ 49 Kronverksky Av St Petersburg 197101 Russia

The basis of this work is a modification of the modern design of surgical binoculars based on substitution of mineral glasses with polymer lenses. Aberration analyses of the proposed systems is shown.

ISBN: (纸本)9781510612082;9781510612075

关键词： polymeric lenses medical optics surgical binoculars optical system design ergonomics

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