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半导体在直流电调整上的应用

电网技术 1957年第1期 98-104页

作者：贺季坚,陈道元,f.h贾塞(chaoe) 电力部技术改进局电气研究室电力部技术改进局电气研究室

半导体以晶体二极管和三极管的形式已广泛地用于整流,电子放大,通讯及计算等等迴路,但是关于它们代替电子管,磁放大器和二极充气管来对电力进行调整控制的应用方面,过去很少提到,现在来谈一下这方面的几种方法,尤其着重它们在直流电压... 详细信息

半导体以晶体二极管和三极管的形式已广泛地用于整流,电子放大,通讯及计算等等迴路,但是关于它们代替电子管,磁放大器和二极充气管来对电力进行调整控制的应用方面,过去很少提到,现在来谈一下这方面的几种方法,尤其着重它们在直流电压及电流调节上的应用。

关键词：晶体电压大畏

Preserving the literary past, looking to the future: the first hong Kong Literature Database

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1341-1347页

作者： MA Leo f.h. WONG Rita LAU Paul University Library System The Chinese University of Hong Kong Hong Kong ChinaUniversity Library System The Chinese University of Hong Kong Hong Kong ChinaUniversity Library System The Chinese University of Hong Kong Hong Kong China

In the last two decades of the 20th century, there has been an increasing interest in and emphasis on the study of the hong Kong literature in both the academic and general public in hong Kong. Recognizing the emergent need of the resources on hong Kong literature, the University Library System of the Chinese University of.hong Kong set up the hong Kong Literature Database （the “Database”）, which was the first Chinese literature database in the Internet in 2000. The paper will examine how the database is constructed using XML technology andometadata schema, The database also employs Unicode UTf-8 as the internal code. A mapping table for traditional and simplified Chinese characters was created based on Unihan and is used behind the scene so that a user can either input traditional or simplified Chinese characters and retrieval will give both traditional and simplified Chinese characters. Currently 65% of journals use OCR technology so that full-text searching is possible. The Chinese OCR technology will be examined in greater detail. Special features of the Database such as, page-by-page browse mode, position-highlight for full-page newspaper, linking Table-Of-Contents and book jackets from the Library catalogue, etc. are described. The paper will also bring out the problem of massive downloading and compare the state-of-the-art technology and their shortcomings. This paper shows how the hong Kong Literature Database facilitates future collaboration and data exchange by using open standard, shareable structure and the latest technology.

关键词： hong Kong Literature hong Kong Literature Database XML Metadata schema Database structure UnicodeUTf-8 OCR technology

Beam dynamics design and electromagnetic analysis of 3 MeV RfQ for TAC Proton Linac

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Nuclear Science and Techniques 2015年第3期26卷 11-16页

作者： A.Caliskan h.f.Kisoglu M.Yilmaz Department of Physics Engineering Gumushane University Department of Physics Aksaray University Physics Department Gazi University

A beam dynamics design of 352.2 Mhz radio-frequency quadrupole(RfQ) of Turkish Accelerator Center(TAC) project which accelerates continuous wave(CW) proton beam with 30 m A current from 50 ke V to3 Me V kinetic energy has been performed in this study. Also, it includes error analysis of the RfQ, in which some fluctuations have been introduced to input beam parameters to see how the output beam parameters are affected, two-dimensional(2-D) and three-dimensional(3-D) electromagnetic structural design of the RfQ to obtain optimum cavity paramaters that agree with the ones of the beam dynamics. The beam dynamics and error analysis of the RfQ have been done by using ***. Electromagnetic design parameters have been obtained by using SUPERfISh for 2-D cavity geometry and CST Microwave Studio for 3-D cavity geometry.

关键词：质子直线加速器束流动力学动力学设计电磁分析 RfQ MeV 结构设计参数误差分析

Rolling in Nature and Robotics: A Review

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Journal of Bionic Engineering 2006年第4期3卷 195-208页

作者： Rhodri h.Armour Julian f.V.Vincent Centre for Biomimetic and Natural Technologies Department of Mechanical Engineering University of Bath Bath BA2 7AY UK

This paper presents a review of recent rolling robots including Rollo from helsinki University of Technology, Spherical Mobile Robot from the Politecnico of Bad, Sphericle from the University of Pisa, Spberobot from Michigan State University, August from Azad University of Qazvin and the University of Tehran, Deformable Robot from Ritsumeijan University, Kickbot from the Massachusetts Institute of Technology, Gravitational Wheeled Robot from Kinki University, Gyrover from Carnegie Mellon University, Roball from the Université de Sherbrooke, and Rotundus from the Angstroem Space Technology Center. Seven rolling robot design principles are presented and discussed （Sprung central member, Car driven, Mobile masses, hemispherical wheels, Gyroscopic stabilisation, Ballast mass - fixed axis, and Ballast mass - moving axis）. Robots based on each of the design principles are shown and the performances of the robots are tabulated. An attempt is made to grade the design principles based on their suitability for movement over an unknown and varied but relatively smooth terrain. The result of this comparison suggests that a rolling robot based on a mobile masses principle would be best suited to this specific application. Some wonderful rolling organisms are introduced and defined as ＂active＂ or ＂passive＂ depending on whether they generate their own rolling motion or external forces cause their rolling.

关键词： Rolling robot tumbleweed wheel ballast Gryoscope

Conformable fractional Nikiforov–Uvarov Method

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Communications in Theoretical Physics 2016年第7期65卷 12-18页

作者： h.Karayer D.Demirhan f.Buyukkilic Department of Physics Faculty of Science Ege University，35100 Bornova，Izmir，Turkey

We introduce conformable fractional Nikiforov–Uvarov(NU) method by means of conformable fractional derivative which is the most natural definition in non-integer calculus. Since, NU method gives exact eigenstate solutions of Schr¨odinger equation(SE) for certain potentials in quantum mechanics, this method is carried into the domain of fractional calculus to obtain the solutions of fractional SE. In order to demonstrate the applicability of the conformable fractional NU method, we solve fractional SE for harmonic oscillator potential, Woods–Saxon potential, and hulthen potential.

关键词： fractional calculus fractional differential equations conformable fractional derivative conformable fractional Nikiforov-Uvarov method

On the formation of shear bands in a metallic glass under tailored complex stress fields

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Journal of Materials Science & Technology 2020年第18期52卷 112-117页

作者： S.h.Chen T.Li W.J.Chang h.D.Yang J.C.Zhang h.h.Tang S.D.feng f.f.Wu Y.C Wu School of Mechanical Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China School of Materials Science and Engineering Liaoning University of TechnologyJinzhou 121001China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

The formation of shear bands in metallic glasses(MGs)was examined by tailoring localized complex stress fields(LCSfs).The findings have shown that the LCSfs in MGs can increase the localization of strained atoms and accelerate the release of accumulated deformation energy for initiating a shear band in confined and thin-layered *** findings not only add more knowledge to the formation mechanisms of shear bands in MGs,but also provide possible rationale for the discrepancies in the mechanical properties of different-sized *** compared with the bulk samples,the higher strength and larger elastic limits in nanoscaled MGs could be attributed to the elimination of stress-concentrators,which can serve as LCSfs.

关键词： Localized complex stress field Shear band Metallic glass Molecular dynamics simulation Size effect

Effects of aluminum co-doping on photoluminescence properties of Ce^(3+)-doped SiO_2 glasses

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Journal of Rare Earths 2010年第S1期28卷 206-210页

作者： Lf KOAO h.C.SWART f.B.DEJENE Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba9866South Africa Department of Physics University of the Free StateP.O.Box 339Bloemfontein9300South Africa

SiO2 glasses co-doped with Al3+ ions were prepared by a sol-gel method by holding 0.5% of Ce3+ ions constant and varying the Al3+ ions *** stability,the structural,chemical and the optical properties of the samples were studied by using differential scanning calorimetric(DSC),thermo gravimetric analysis(TGA),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),UV-vis spectroscopy and photoluminescence spectroscopy(PL).The DSC and TGA of samples depicted that the presence of dopant and co-dopant decreased the endothermic peak temperature and the yield *** images showed that the particles were in the nano-range and spherical in *** XRD showed that all the samples were *** UV absorption measurements indicated that the presence of Al3+ ions significantly reduced the SiO2 absorption band,increased the absorbance intensity of SiO2 and decreased the transmittance as compared to the presence of the Ce3+ ions *** photoluminescence results displayed an optimum increase in luminescence intensity when the ratio of Al:Ce was 10:1 and further increase in aluminum content quenched the luminous intensity.

关键词： SiO2:Ce Al when sol-gel molar ration nano-size luminescence enhancement rare earths

Supplementary optical solitonic expressions for Gerdjikov–Ivanov equations with three Kudryashov-based methods

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Communications in Theoretical Physics 2024年第12期76卷 3-14页

作者： f A Althrwi A A Alshaery h O Bakodah Rahmatullah Ibrahim Nuruddeen Department of Mathematics and Statistics Faculty of Science University of Jeddah Department of Mathematics Faculty of Physical Sciences Federal University Dutse

The present manuscript uses three Kudryashov-based methods to analytically inspect the class of Gerdjikov–Ivanov equations, which comprises the standard Gerdjikov–Ivanov equation and the perturbed Gerdjikov–Ivanov equation. Various optical solitonic solutions have been ***, as the reported solitonic structures happened to be exponential functions, diverse true solitonic solutions can easily be resorted to upon suitably fixing the involving parameters,including mainly the bright and singular solitons. Lastly, the study graphically examined some of the constructed structures, which were then found to portray some interesting known shapes in the theory of solitary waves and nonlinear Schr?dinger equations. Additionally, the Kudryashovindex d has been noted to play a significant role in the propagation of complex waves in the nonlinear media described by Gerdjikov–Ivanov equations.

关键词： Gerdjikov-Ivanov equation Kudryashov-based methods perturbed Gerdjikov-Ivanov equation Schrödinger equations solitonic solutions

Structural,magnetic and electrical characterization of the La_(0.7)Ca_(0.3)Co_(1–x)Mn_xO_3(x=0,0.7 and 1) compounds prepared by a simple method

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Journal of Rare Earths 2014年第10期32卷 965-972页

作者： M.Eshraghi P.Kameli f.Khalili M.h.Ehsani h.Salamati Department of Physics Payame Noor University Department of Physics Isfahan University of Technology Department of Physics Semnan University

Structural, magnetic and electrical properties of the La0.7Ca0.3Co1–xMnxO3（x=0, 0.7 and 1） samples prepared by a simple method were systematically studied and it was found that the crystal structure was transformed from rhombohedral for La0.7Ca0.3CoO3（LCCO） and La0.7Ca0.3Co0.3Mn0.7O3（LCCMO） samples to orthorhombic for La0.7Ca0.3MnO3（LCMO） sample. The AC magnetic susceptibility measurements showed that LCCO sample underwent a transition from paramagnetic（PM） to ferromagnetic（fM） phase at Curie temperature, TC^155 K and below Curie temperature, the glassy ferromagnetism nature was observed. In LCCMO sample,clear evidence of spin glass（SG） state was observed at low temperature. PM-fM phase transition at about TC^260 K and long range fM order at low temperatures were observed in LCMO sample. Both the LCCO and LCCMO samples exhibited insulating behavior in the whole range of measuring temperature whereas the LCMO sample underwent a clear metal-insulator（MI） transition at about TMI^263 K, corresponding to Curie temperature. Metallic region of ρ（T） curve of the LCMO sample was fitted to the model of electron-electron and electron-magnon scattering. The charge carrier transport behavior in all the samples was compared based on polaronic models.

关键词： cobaltite spin glass manganites rare earths