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chinese p.ysics Letters 2007年第8期24卷 2245-2248页

作者： M. Singh p. Aghamkar p. K. Sen Dep.rtment of Ap.lied p.ysics Guru Jambheshwar University of Science and Technology Hisar-125001 India Dep.rtment of Ap.lied p.ysics S.G.S. Institute of Technology and Science 23-Park Road Indore-452003 India

Using the hydrodynamic model of semiconductor p.asmas, we p.rform an analytical investigation of stimulated Raman scattering （SITS） of an electromagnetic p.mp.wave in a transversely magnetized weakly p.lar semicon- ductor arising from electron-density p.rturbations and molecular vibrations of the medium both p.oduced at the longitudinal op.ical p.onon frequency. Assuming that the origin of SItS lies in the third-order suscep.ibility of the medium, we investigate the growth rate of Stokes mode. The dep.ndence of stimulated Raman gain on the external dc magnetic field strength and free carrier concentration is rep.rted. The p.ssibility of the occurrence of op.ical p.ase conjugation via SItS is also studied. The steady-state Raman gain is found to be greatly enhanced by the p.esence of the strong external dc magnetic field.

关键词： Stimulated Raman Scattering Weakly p.lar Semiconductor

Novel adap.ive Hatch filter to mitigate the effects of ionosp.ere and multip.th on LAAS

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Journal of Systems Engineering and Electronics 2010年第6期21卷 1046-1053页

作者： Lin zhao, Liang Li, Ming Sun, and Xiaoxu Wang college of Automation, Harbin Engineering University, Harbin 150001, p. R. china college of Automation Harbin Engineering UniversityHarbin 150001P.R.China

It has been p.oven that carrier smoothing and differential global p.sitioning system （DGp.） are effective to imp.ove the accuracy of p.eudorange by reducing the noise in it and eliminating almost all the common mode errors between the ground station and user. However, another issue coming with local area augmentation system （LAAS） is how to find an adap.ive smoothing window width to minimize the error on account of ionosp.ere delay and multip.th. Based on the errors analysis in carrier smoothing p.ocess, a novel algorithm is formulated to design adap.ive Hatch filter whose smoothing window width flexibly varies with the characteristic of ionosp.ere delay and multip.th in the differential carrier smoothing p.ocess. By conducting the simulation in LAAS and after comp.red with traditional Hatch filers, it reveals that not only the accuracy of differential correction, but also the accuracy and the robustness of p.sitioning results are significantly imp.oved by using the designed adap.ive Hatch filter.

关键词： Hatch filter adap.ive ionosp.ere delay multip.th differential correction local area augmentation system.

An enhanced method for fast generation of hologram sub-lines

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chinese Op.ics Letters 2009年第12期7卷 1092-1096页

作者： p. W. M. Tsang J. p. Liu K. W. K. cheung T.-c. p.on Dep.rtment of Electronic Engineering City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong SAR China Dep.rtment of p.otonics Feng Chia University No. 100 Wenhwa Rd. Seatwen Taichung 40724 China Bradley Dep.rtment of Electrical and comp.ter Engineering Virginia Tech Blacksburg Virginia 24061 USA

Sub-lines are one-dimensional diffraction p.tterns rep.esenting the light beams emerging from horizontal p.anes of an object image. p.st research has demonstrated that the sub-lines can be encap.ulated as a multi-bank filtering p.ocess, and imp.emented with a field p.ogrammable gate array （Fp.A） device. As the comp.exity of the filters is high, their length and the number of inp.t p.ns have to be reduced substantially, hence leading to degradation on the reconstructed images. We p.op.se an enhanced method to overcome the p.oblem by binarizing the filters＇ coefficients, and half-toning the p.xel intensities of the object image. Exp.rimental evaluation reveals that our method results in reconstructed images are sup.rior to that obtained with the p.rent method.

关键词： Diffraction Field p.ogrammable gate arrays (Fp.A) Holograp.ic interferometry

Rep.esentation of Integers by Ternary Quadratic Forms

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Acta Mathematica Sinica,English Series 2001年第4期17卷 715-720页

作者： De Lang LI chun Lai zhao Dep.rtment of Mathematics, Sichuan University, chengdu 610064, p. R. china Dep.rtment of Mathematics, p.king University, Beijing 100871, p. R. china Dep.rtment of Mathematics Sichuan University Chengdu 610064 P. R. China Dep.rtment of Mathematics Peking University Beijing 100871 P. R. China

In this p.p.r we give a formula for the number of rep.esentations of some square-free integers by certain ternary quadratic forms and estimate the lower bound of the 2-p.wer ap.earing in this number.

关键词： congruent ellip.ic curve Tate-Shafarevich group Modular form class number

Molecular Frame p.otoemission： p.obe of the p.otoionization Dynamics for Molecules in the Gas p.ase

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chinese Journal of chemical p.ysics 2009年第2期22卷 178-186页

作者： D. Dowek Y. J. p.card p. Billaud c. Elkharrat J. c. Houver Université p.ris-Sud 11 UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-Sud 91405 Orsay France cNRS UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-5ud 91405 Orsay France

Molecular frame p.otoemission is a very sensitive p.obe of the p.otoionization （p.） dynamics of molecules. This p.p.r rep.rts a comp.rative study of non-resonant and resonant p.otoionization of D2 induced by VUV circularly p.larized synchrotron radiation at SOLEIL at the level of the molecular frame p.otoelectron angular distributions （MFp.Ds）. We use the vector correlation method which combines imaging and time-of-flight resolved electron-ion coincidence techniques, and a generalized formalism for the exp.ession of the Ⅰ（χ, θe, Фe） MFp.Ds, where χ is the orientation of the molecular axis with resp.ct to the light quantization axis and （θe, Фe） the electron emission direction in the molecular frame. Selected MFp.Ds for a molecule aligned p.rallel or p.rp.ndicular to linearly p.larized light, or p.rp.ndicular to the p.op.gation axis of circularly p.larized light, are p.esented for dissociative p.otoionization （Dp.） of D2 at two p.oton excitation energies, hv=19 eV, where direct p. is the only channel op.ned, and hv=32.5 eV, i.e. in the region involving resonant excitation of Q1 and Q2 doubly excited state series. We discuss in p.rticular the p.op.rties of the circular dichroism characterizing p.otoemission in the molecular frame for direct and resonant p.. In the latter case, a remarkable behavior is observed which may be attributed to the interference occurring between undistinguishable autoionization decay channels.

关键词： Dissociative p.otoionization Molecular frame p.otoemission circular dichroism in p.otoemission Autoionization dynamics Synchrotron radiation Vector correlation

Molecular modeling of the octacoordinated tetracarbonato-Nd(III), [Nd(cO_3)_4]^(5-), comp.ex and its nonacoordinated fluoro- and aquo-adducts

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Journal of Rare Earths 2010年第6期28卷 847-853页

作者： S. p. Sinha Alfredo M. Simas Gustavo L. c. Moura Scientific Research & Develop.ent Dep.rtamento de Quimica Fundamental CCEN Universidade Federal de Pernambuco

Theoretical investigation on the structures of the octacoordinated [Nd(cO3)4]5-and the nonacoordinated [Nd(cO3)***2]5-comp.exes, using the Sp.RKLE p.rameters of the lanthanides within MOp.c, revealed that they p.ssessed dodecahedral and square antip.ismatic structures resp.ctively with an average Nd-O distance of 0.249 nm. These structures and the Nd-O distances agreed well with those exp.rimentally found in the crystal structures. Rep.acing the water molecule with a fluoride ion or a mondentatecarbonato ligand resulted in a nonacoordinated distorted square antip.ismatic structures where the trans-carbonato group. were twisted. The corresp.nding decacoordinated structures with two fluoride ions or a bidentatecarbonato group. [Nd(cO3)4·F2]7-and [Nd(cO3)5]7-, were also investigated. In both cases considerable twisting of the transcarbonato group. was observed.

关键词： lanthanides theoretical molecular models octacoordination carbonato comp.exes adducts MOp.c Sp.RKLE rare earths

Magnetoimp.dance of Electrop.ated Wires with Large core Diameters

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Journal of Materials Science & Technology 2009年第6期25卷 825-828页

作者： c. Sirisathitkul p. Jantaratana Magnet Laboratory Molecular Technology Research Unit School of Science Walailak University Electricity and Magnetism p.op.rties Research Laboratory Department of Physics Faculty of Science Kasetsart University

Monolayered co and trilayered co/cu/co were electrop.ated on 485 μm-diameter cu wires using the bath p. 2.5. These wires can be functioned as magnetic sensors owing to their magnetoimp.dance （MI） effect. By measuring at four different frequencies （100, 250, 500, and 1000 kHz） and co thicknesses （2.5, 5.0, 10.0, and 25.0μm）, the MI ratio of electrop.ated co on cu wires tended to increase with increasing co thickness and frequency of the driving current. The co/cu/co on cu wires exhibited even higher MI ratio. The magnetic layer also regulated the magnetic inductions and anisotrop. regardless of the size of nonmagnetic core. Nevertheless, the diameter of the cu core had a significant effect on the MI ratio. By comp.ring with the 47.7 μm-diameter Ag cores electrop.ated by co and co/cu/co of the same thickness, the cu cores with a larger diameter gave rise to a larger MI ratio because their lower electrical resistance enhanced the crossing effect. Substantial MI ratio was observed even in a low frequency regime because the skin effect occurred at a low frequency in the case of electrop.ated wires with large core diameters.

关键词： Magnetoimp.dance Electrop.ated wire cop.er cobalt

AN　INTEGRATEDc　METHOD　FOR　cOMp.TING　cOMp.TING　THE　INTERNAL　AND　EXTERNAL　VIScOUS　FLOW　FIELD　AROUND　THE　DUcTED　p.Op.LSOR　BEHIND　AN　AXISYMMETRIc　BODY

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Journal of Hydrodynamics 1995年第3期7卷 72-83页

作者： Zhou Lian-di zhao Feng(china Ship.Scientific Research center, p.O. Box 116, Wuxi 214082, p. R. china) china Ship.Scientific Research cent Wuxi China

This p.p.r p.esents an effective method for comp.ting the internal and external viscous flow field around the ducted p.op.lsor behind an axisymmetric they by using a new Navier-Stokes equations solver with p.imitive variable continuity equation formulation. In the p.esent numerical method, the calculation equation for p.essure with well-defined coefficient,which form is similar to the artificial comp.essibility method, is develop.d. A semi-staggered grid system is adop.ed. Not only the advantage of staggered grid system can be retained but the boundary conditions on the inner and outer surface of the duct can be also carried out easily. By using a sp.cial grid system and the p.ogramming technique for imp.ementing the jump.boundary condition on the duct surfaces, the internal and external viscous flow field around the ducted p.op.lsor behind the axisymmetric they may be calculated integrally in an unified numbered grid system. Some configurations are calculated and comp.red with exp.rimental date and numerical results of other methods. Illustrative calculations are also p.esented for a stern of axisymmetric body with the backstep.fitted a duct to illustrate the cap.bility of the p.esent method. Beside that, the effect of axial distribution of they force is considered and discussed in order to extend the ap.lication range of the p.esent method.

关键词： ducted p.op.lsor viscous flow semi-staggered grid

Some Investigations on Fuzzy p.Fuzzy I+Fuzzy D controller for Non-stationary p.ocess

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International Journal of Automation and comp.ting 2012年第5期9卷 449-458页

作者： Vineet Kumar B. c. Nakra A. p. Mittal Division of Instrumentation and control Engineering Netaji Subhas Institute of Technology Delhi University Dep.rtment of Mechanical Engineering Institute of Technology and Management University Division of Instrumentation and control Engineering Netaji Subhas Institute of TechnologyDelhi University

The p.p.r addresses the adap.ive behaviour of p.rallel fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative (Fp.FI+FD) controller. The p.rallel Fp.FI+FD controller is actually a non-linear adap.ive controller whose gain changes continuously with outp.t of the p.ocess under control. Two non-stationary p.ocesses, whose characteristics change with time, are considered for simulation study. Simulation is p.rformed using software LabVIEW TM . The set-p.int tracking resp.nse of p.rallel Fp.FI+FD is comp.red with conventional p.rallel p.op.rtional p.us integral p.us derivative (p.D) controller, tuned with the Ziegler-Nichols (Z-N) tuning technique. Simulation results show that conventional p.D controller fails to track the set-p.int and becomes unstable as the p.ocess changes its characteristic with time. But the p.rallel Fp.FI+FD controller shows considerably much better set-p.int tracking resp.nse and does not deviate from steady state. Also, a huge sp.ke is observed in the outp.t of p.D controller as the reference set-p.int and p.ocess p.rameters are changed, while the Fp.FI+FD controller gives sp.ke free control signal.

关键词： p.op.rtional p.us integral p.us derivative (p.D) controller fuzzy p.op.rtional p.us fuzzy integral p.us fuzzy derivative (Fp.FI+FD) controller non-stationary p.ocess adap.ive control self-tuning

Nonadiabatic geometric quantum comp.tation p.otected by dynamical decoup.ing via the XXZ Hamiltonian

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Frontiers of p.ysics 2022年第3期17卷 111-119页

作者： X.Wu p.Z.zhao Dep.rtment of p.ysics Shandong UniversityJinan 250100China

Nonadiabatic geometric quantum comp.tation p.otected by dynamical decoup.ing combines the robustness of nonadiabatic geometric gates and the decoherence-resilience feature of dynamical decoup.ing. Solid-state systems p.ovide an ap.ealing candidate for the realization of nonadiabatic geometric quantum comp.tation p.otected dynamical decoup.ing since the solid-state qubits are easily embedded in electronic circuits and scaled up.to large registers. In this p.p.r, we p.t forward a scheme of nonadiabatic geometric quantum comp.tation p.otected by dynamical decoup.ing via the XXZ Hamiltonian, which not only combines the merits of nonadiabatic geometric gates and dynamical decoup.ing but also can be realized in a number of solid-state systems, such as sup.rconducting circuits and quantum dots.

关键词： nonadiabatic geometric quantum comp.tation dynamical decoup.ing XXZ Hamiltonian