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一种收发同时工作的集成有源阵天线

东南大学学报（自然科学版） 1997年第4期27卷 118-121页

作者：沙济彰 Hall,ps 河海大学常州分校

一种收发同时工作的集成有源阵天线沙济彰Ｐ．Ｓ．ＨａｌＭ．Ｊ．Ｃｒｙａｎ（河海大学常州分校，常州２１３０２２）（ＵｎｉｖｅｒｓｉｔｙｏｆＢｉｒｍｉｎｇｈａｍ，Ｂｉｒｍｉｎｇｈａｍ，Ｂ１５２ＴＴ，Ｕ．Ｋ．）有源天线是指... 详细信息

一种收发同时工作的集成有源阵天线沙济彰Ｐ．Ｓ．ＨａｌＭ．Ｊ．Ｃｒｙａｎ（河海大学常州分校，常州２１３０２２）（ＵｎｉｖｅｒｓｉｔｙｏｆＢｉｒｍｉｎｇｈａｍ，Ｂｉｒｍｉｎｇｈａｍ，Ｂ１５２ＴＴ，Ｕ．Ｋ．）有源天线是指把有源器件集成到天线之中，或将两者...

关键词：有源阵天线收发同时工作接地天线微带天线

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屏蔽罩中场强的测量

空间电子技术 1994年第94期 10-16,36页

作者： Cook R j Bansal ps Alexander 孙永明季荣昌英国国家物理实验室

屏蔽室测量(30～200MHz) 1 引言本文描述了如何有选择地放置辐射吸收材料(RAM),这种材料能够大大减小无衬屏蔽室中产生的电磁谐振的Q值。在屏蔽室中完成的EMC(电磁兼容性)性能试验结果与在其他室中进行的同样检测通常相差20dB或更多。... 详细信息

屏蔽室测量(30～200MHz) 1 引言本文描述了如何有选择地放置辐射吸收材料(RAM),这种材料能够大大减小无衬屏蔽室中产生的电磁谐振的Q值。在屏蔽室中完成的EMC(电磁兼容性)性能试验结果与在其他室中进行的同样检测通常相差20dB或更多。这些结果由室谐振、天线位置和室内的EUT(被检测设备)决定。已对这些谐振做了详细研究,提到的衰减方法使发射测量同在开场区所做的、在30～200MHz频域内的一致性达到5dB以内。

关键词：屏蔽罩场强测量 EMC

Power management unit chip design for automobile active-matrix organic light-emitting diode display module

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journal of Central South University 2009年第4期16卷 621-628页

作者： KIM j H PARK j H KIM j H CAO T V LEE T Y BAN H j YANG K KIM H G HA P B KIM Y H Department of Electronic Engineering Changwon National University 9 Sarim-Dong Changwon 641-773 Korea Denso ps Electronics Corporation 47 Seongsan-Dong Changwon 641-315 Korea

A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.

关键词： DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage

Technology development for ultraintense all-OPCPA systems

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High Power Laser Science and Engineering 2019年第1期7卷 27-37页

作者： j.Bromage S.-W.Bahk I.A.Begishev C.Dorrer M.j.Guardalben B.N.Hoffman j.B.Oliver R.G.Roides E.M.Schiesser M.j.Shoup III M.Spilatro B.Webb D.Weiner j.D.Zuegel Laboratory for Laser Energetics University of Rochester

Optical parametric chirped-pulse amplification(OPCPA) [Dubietis et al., Opt. Commun. 88, 437(1992)] implemented by multikilojoule Nd:glass pump lasers is a promising approach to produce ultraintense pulses(>1023 W/cm2).Technologies are being developed to upgrade the OMEGA EP Laser System with the goal to pump an optical parametric amplifier line(EP OPAL) with two of the OMEGA EP beamlines. The resulting ultraintense pulses(1.5 kj, 20 fs,1024 W/cm2) would be used jointly with picosecond and nanosecond pulses produced by the other two beamlines. A midscale OPAL pumped by the Multi-Terawatt(MTW) laser is being constructed to produce 7.5-j, 15-fs pulses and demonstrate scalable technologies suitable for the upgrade. MTW OPAL will share a target area with the MTW laser(50 j, 1 to 100 ps), enabling several joint-shot configurations. We report on the status of the MTW OPAL system, and the technology development required for this class of all-OPCPA laser system for ultraintense pulses.

关键词： nonlinear optics optical parametric chirped-pulse amplification ultrafast lasers ultraintense lasers

Ultrafast laser-driven topological spin textures on a 2D magnet

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npj Computational Materials 2022年第1期8卷 1630-1635页

作者： Mara Strungaru Mathias Augustin Elton j.G.Santos Institute for Condensed Matter Physics and Complex Systems School of Physics and AstronomyThe University of EdinburghEdinburghEH93FDUK Donostia International Physics Center(DIPC) 20018Donostia-San SebastiánBasque CountrySpain Higgs Centre for Theoretical Physics The University of EdinburghEdinburghEH93FDUK

Ultrafast laser excitations provide an efficient and low-power consumption alternative since different magnetic properties and topological spin states can be triggered and manipulated at the femtosecond(fs)***,it is largely unknown whether laser excitations already used in data information platforms can manipulate the magnetic properties of recently discovered two-dimensional(2D)van der Waals(vdW)*** we show that ultrashort laser pulses(30−85 fs)can not only manipulate magnetic domains of 2D-XY CrCl_(3)ferromagnets,but also induce the formation and control of topological nontrivial meron and antimeron spin *** observed that these spin quasiparticles are created within~100 ps after the excitation displaying rich dynamics through motion,collision and annihilation with emission of spin waves throughout the *** findings highlight substantial opportunities of using photonic driving forces for the exploration of spin textures on 2D magnetic materials towards magneto-optical topological applications.

关键词： laser excitation topological

3rd ANtarctic Gravity Wave Instrument Network(ANGWIN)Science Workshop

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Advances in Atmospheric Sciences 2017年第1期34卷 1-3页

作者： Tracy MOFFAT-GRIFFIN Mike j.TAYLOR Takuji NAKAMURA Andrew j.KAVANAGH j.Scott HOSKING Andrew ORR Britsh Antarctic survey High CrossCambridge CB30ETUK Utah State University LoganUT84322USA National Institute of Polar Research Tachikawa-shiTokyo 190-8518Japan

1. Overview The 3rd ANtarctic Gravity Wave Instrument Network （ANGWIN） science workshop was held on 12-14 April 2016 in Cambridge, UK. ANGWIN is a highly successful grassroots program that was started in 2011 （in the Cornish English dialect ANGWIN means ＂the white＂）. Although ini- tially focused on the Antarctic, we now aim to develop collaborations in both polar regions.

关键词： ANGWIN)Science Workshop Wave

Triassic (Anisian and Rhaetian) palaeomagnetic poles from the Germanic Basin (Winterswijk, the Netherlands)

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journal of Palaeogeography 2019年第4期8卷 393-407页

作者： Lars P.P.van Hinsbergen Douwe j.j.van Hinsbergen Cor G.Langereis Mark j.Dekkers Bas Zanderink Martijn H.L.Deenen Fioretti College Sportlaan 32161 VA Lissethe Netherlands Department of Earth Sciences Utrecht UniversityPrincetonlaan 8A3584 CB Utrechtthe Netherlands Twents Carmel College De Thij Thijlaan 307576 ZB Oldenzaalthe Netherlands.

In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian *** were respectively collected from the Anisian(~247–242 Ma)red marly limestones of the sedimentary transition of the Buntsandstein Formation to the dark grey limestones of the basal Muschelkalk Formation,and from the Rhaetian(~208–201 Ma)shallow marine claystones that unconformably overlie the Muschelkalk *** magnetization is carried by hematite or magnetite in the Anisian limestones,and iron sulfides and magnetite in the Rhaetian sedimentary rocks,revealing for both a large normal polarity overprint with a recent(geocentric axial dipole field)direction at the present latitude of the *** field and thermal demagnetization occasionally reveal a stable magnetization decaying towards the origin,interpreted as the Characteristic Remanent *** we find a pervasive(normal polarity)overprint,we can often still determine well-defined great-circle *** interpreted palaeomagnetic poles include the great-circle *** Anisian magnetic pole has declination D±ΔDx=210.8±3.0°,inclination I±ΔIx=-26.7±4.9°,with a latitude,longitude of 45.0°,142.0°respectively,K=43.9,A95=2.9°,N=*** Rhaetian magnetic pole has declination D±ΔDx=32.0±8.7°,inclination I±ΔIx=50.9±8.1°,with a latitude,longitude of 60.6°,123.9°respectively,K=19.3,A95=7.4°,N=*** poles plot close to the predicted location of global apparent polar wander paths(GAPWa ps)in Eurasian coordinates and are feasible for future apparent polar wander path *** confirm that the intracontinental,shallow-marine Germanic Basin,in which the Muschelkalk Formation was deposited,existed at a palaeolatitude of 14.1°[11.3,17.1]N,in a palaeo-environment reminding of the Persian Gulf *** Rhaetian times,palaeolatitudes of 31.6°[24.8,39.8]N were reached,on its way to the modern latitude of 52°N.

关键词： Palaeomagnetic Palaeolatitude Anisian Rhaetian Muschelkalk Formation Germanic Basin

Excitation and relaxation dynamics in ultrafast laser irradiated optical glasses

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： C.Mauclair A.Mermillod-Blondin K.Mishchik j.Bonse A.Rosenfeld j.P.Colombier R.Stoian Laboratoire Hubert Curien UMR 5516 CNRSUniversité de LyonUniversité Jean Monnet Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie Bundesanstalt für Materialforschung und-prüfung (BAM)

We discuss the dynamics of ultrashort pulsed laser excitation in bulk optical silica-based glasses(fused silica and borosilicate BK7) well-above the permanent modification threshold. We indicate subsequent structural and thermomechanical energy relaxation paths that translate into positive and negative refractive index changes, compression and rarefaction zones. If fast electronic decay occurs at low excitation levels in fused silica via self-trapping of excitons,for carrier densities in the vicinity of the critical value at the incident wavelength, persistent long-living absorptive states indicate the achievement of low viscosity matter states manifesting pressure relaxation, rarefaction, void opening and compaction in the neighboring domains. An intermediate ps-long excited carrier dynamics is observed for BK7 in the range corresponding to structural expansion and rarefaction. The amount of excitation and the strength of the subsequent hydrodynamic evolution is critically dependent on the pulse time envelope, indicative of potential optimization schemes.

关键词： carrier plasmas glasses pulse shaping refractive index engineering ultrafast laser excitation

A Raman laser system for multi-wavelength satellite laser ranging

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 737-743页

作者： K.Hamal I.Prochazka j.Blazej Czech Technical University in Prague CzechCzech Technical University in PragueCzechCzech Technical University in PragueCzech

In order to develop a laser system for multi-wavelength satellite laser ranging, the joint group of the Shanghai Astronomical Observatory and the Czech Technical University has studied the conversion efficiency of the Raman-shifting beam and its spatial characteristics. We adopted a 0.53 μm laser with pulse width of 35 ps and peak energy of 35 mj, the second harmonic of a Nd:YAG actively and passively mode-locked laser, to pump a one-meter-long Raman tube which is full of H2 with high pressure at the Prague-based laboratory. We get the first Stokes laser (0.68 μm): 7 mj (single pulse) with beam divergence of 40″ (arcsecond) and spatial wobbling of less than 4″; and the first anti-Stokes laser (0.43 μm): 2 mj (single pulse) with divergence of 56″ and spatial wobbling of less than 4″. The emitting beam from the Raman cell also includes 0.53 μm: 10 mj (single pulse) with divergence of 40″ and spatial wobbling of less than 7″. According to the radar link equation and based on the above obtained multi-wavelength’s energy, we can estimate the detection probabilities for three colors respectively. It is shown by the result that the developed multi-wavelength Raman laser system has the capability of satellite ranging. The Raman laser system will be installed at the laser station in Shanghai Astronomical Observatory to research the multi-wavelength satellite laser ranging.

关键词： multi-wavelength satellite laser ranging, Raman laser, atmosphere correction, detection probability.