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61.
顾永建 《大学物理》2002,21(1):29-31
提出一个令人困惑的电磁感应问题,并运用电磁学理论对其进行了详尽的理论分析。  相似文献   
62.
1 Introduction  Inrecentyears,boththetheoreticalandexperimentalinvestigationsonlasercoolingandtrappinghavebecomeoneofthemajorfieldsinatomic,molecularandoptical physics[1~ 8] .Thedevelopmentoflasercoolingandtrappingtechnologyisimportantfortheapplicationssu…  相似文献   
63.
The behavior of a two-level entangled atom in an optical field with circular polarization is studied in this paper. The interaction of an optical field and one of the entangled atoms is analyzed in detail. A general solution of the SchrAo¨Gdinger equation about the motion of the entangled atom is obtained. The properties of the action are dependent on the initial state of the atom. By detecting the entangled atom out of the field, we can obtain the state of the other atom moving in the field. It is shown that the state of the atom out of the field will influence the energies of the split-levels of the atom in the field.  相似文献   
64.
CCD摄像机大视场光学镜头的设计   总被引:13,自引:9,他引:4       下载免费PDF全文
为提高CCD摄像机的成像质量,同时使镜头结构紧凑、小型化,在大视场光学镜头的设计中,引入标准二次曲面和偶次非球面。根据初级像差理论,分析了非球面的位置、初始结构参数的求解规律。通过理论计算和ZEMAX光学设计软件的优化,给出工作波长为0.4~0.7μm、全视场角为80°,相对孔径为1∶1.5的镜头设计实例。该镜头由7块镜片组成,包括一个标准二次曲面和两个8次方非球面;在40lp/mm空间频率处的MTF值超过0.85,全视场畸变小于3%,像质优良  相似文献   
65.
In this paper, for the the primes p such that 3 is a divisor of p − 1, we prove a result which reduces the computation of the linear complexity of a sequence over GF(p m) (any positive integer m) with the period 3n (n and p m − 1 are coprime) to the computation of the linear complexities of three sequences with the period n. Combined with some known algorithms such as generalized Games-Chan algorithm, Berlekamp-Massey algorithm and Xiao-Wei-Lam-Imamura algorithm, we can determine the linear complexity of any sequence over GF(p m) with the period 3n (n and p m − 1 are coprime) more efficiently.  相似文献   
66.
Shinjo  Teruya  Mibu  Ko 《Hyperfine Interactions》2002,144(1-4):53-64
Hyperfine Interactions - The giant magnetoresistance (GMR) effect was an epoch-making discovery in the field of magnetic materials research. In this article, studies on magnetic multilayered...  相似文献   
67.
在形变约束的相对论平均场理论框架下, 用TMA, PK1, NL3和NL-SH相互作用对196Pb的超形变态进行了系统研究. 给出了196Pb的位能曲线、基态和超形变态的形变以及超形变态退激的激发能. 196Pb的基态为β2≈-0.15的扁椭球, 超形变激发态为β2≈0.60的长椭球, 激发能在4-5MeV之间, 势阱深度在1-2.2MeV之间. 这些结果与最近观测的实验数据符合得非常好, 表明相对论平均场理论能够较好地描述196Pb超形变转动带带首的能量.  相似文献   
68.
The values of the Higgs mass are obtained for two possibilities of extending the standard model in a way compatible with the existence of a noncommutative structure at high energies. We assume the existence of a big desert between the low energy electroweak scale and the high energy scale Λ=1.1×1017 GeV, where noncommutative features become relevant. We conclude that it is extremely difficult to depart from the Higgs mass value obtained from noncommutative geometry for the standard model with three generations only.  相似文献   
69.
D. Perugini  M. Petrelli  G. Poli 《Physica A》2006,370(2):741-746
In this contribution we present new data resulting from the analysis of concentration patterns of mixed juvenile fragments ejected by a highly explosive volcanic eruption that occurred on Salina Island (Aeolian Islands, Italy) and our aim is to identify the fluid-dynamic regime characterizing the magma mixing process. Concentration patterns are studied by calculating the power spectrum of concentration variability along transects crossing the magma mixing structures. Results indicate that the slope of power spectrum has an average value of about −5/3, according to Kolmogorov law of turbulence, and suggest that the magma mixing process, in the studied conditions, can be approximated by considering the passive scalar mixing hypothesis in homogeneous isotropic turbulent flow. These results represent a first step towards a better understanding of magma mixing processes associated to highly explosive volcanic eruptions and this first step is taken by studying concentration patterns in volcanic rocks by coupling petrological and non-linear dynamics methods.  相似文献   
70.
U Camci  Z Can  Y Nutku  Y Sucu  D Yazici 《Pramana》2006,67(6):1043-1053
We present the explicit form of the symplectic structure of anti-self-dual Yang-Mills (ASDYM) equations in Yang’s J- and K-gauges in order to establish the bi-Hamiltonian structure of this completely integrable system. Dirac’s theory of constraints is applied to the degenerate Lagrangians that yield the ASDYM equations. The constraints are second class as in the case of all completely integrable systems which stands in sharp contrast to the situation in full Yang-Mills theory. We construct the Dirac brackets and the symplectic 2-forms for both J- and K-gauges. The covariant symplectic structure of ASDYM equations is obtained using the Witten-Zuckerman formalism. We show that the appropriate component of the Witten-Zuckerman closed and conserved 2-form vector density reduces to the symplectic 2-form obtained from Dirac’s theory. Finally, we present the Bäcklund transformation between the J- and K-gauges in order to apply Magri’s theorem to the respective two Hamiltonian structures.  相似文献   
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