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101.
为了深入了解真空电弧的引燃过程,测量了直流真空电弧起弧阶段的电弧电压,屏蔽罩电位以及屏蔽罩收集的离子电流等参数,分析了真空电弧的引燃过程,起弧后等离子体的扩散过程,以及纵磁场对等离子体扩散的影响。 相似文献
102.
Bruce Olberding 《Proceedings of the American Mathematical Society》1999,127(7):1917-1921
A weakened version of the Jordan-Hölder theorem is shown to hold for torsion-free finite rank modules over an integral domain precisely when is a Prüfer domain.
103.
Multi-separation, centrifugality and centripetality imply chaos 总被引:4,自引:0,他引:4
Jiehua Mai 《Transactions of the American Mathematical Society》1999,351(1):343-351
Let be an interval. need not be compact or bounded. Let be a continuous map, and be a trajectory of with or . Then there is a point such that . A point is called a centripetal point of relative to if or , and is centrifugal if or . In this paper we prove that if there exist centripetal points of in , then has periodic points of some odd () period . In addition, we also prove that if ) is multi-separated by Fix(), or there exists a centrifugal point of in , then is turbulent and hence has periodic points of all periods.
104.
Given a continuous P0-function F : Rn Rn, we describe a method of constructing trajectories associated with the P0-equation F(x) = 0. Various well known equation-based reformulations of the nonlinear complementarity problem and the box variational inequality problem corresponding to a continuous P0-function lead to P0-equations. In particular, reformulations via (a) the Fischer function for the NCP, (b) the min function for the NCP, (c) the fixed point map for a BVI, and (d) the normal map for a BVI give raise to P0-equations when the underlying function is P0. To generate the trajectories, we perturb the given P0-function F to a P-function F(x, ); unique solutions of F(x, ) = 0 as varies over an interval in (0, ) then define the trajectory. We prove general results on the existence and limiting behavior of such trajectories. As special cases we study the interior point trajectory, trajectories based on the fixed point map of a BVI, trajectories based on the normal map of a BVI, and a trajectory based on the aggregate function of a vertical nonlinear complementarity problem. 相似文献
105.
2005年发生的“普马事件”在中国的零售业界掀起了轩然大波,而事件发生后关于供货商的货款追偿问题更是引人关注。从特许经营的外部责任的角度分析,北京普马和美国普马应对供货商的债权分别承担替代责任和替补责任。 相似文献
106.
J. Westergren S. Nordholm A. Rosén 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(1):81-97
The cooling of the metal cluster Pd13 in an atmosphere of rare gas has been studied by means of computer simulation. By simulation, the average energy transfer
in collisions between one cluster and one gas atom has been obtained. Emphasis has been placed on conditions when the temperatures
of the colliding species are almost equal. All modes of motion, inclusive the translation, must be considered in order to
obtain vanishing energy transfer at equilibrium. A simulation scheme is presented by which the energy transfer is zero to
the cluster when the gas and the cluster temperatures are equal. At equilibrium the energy transfer does however not vanish
for all impact parameters. In the collisions with Pd13, the cluster is heated by collisions with a small impact parameter but equally cooled by collisions with a large impact parameter.
Argon and krypton are found to cool Pd13 equally efficiently while neon and helium are less efficient cooling agents.
Received 28 September 2001 / Received in final form 8 August 2002 Published online 12 November 2002
RID="a"
ID="a"e-mail: JanW@phc.gu.se 相似文献
107.
S. Pellegrin A. Sarfati V.M. Akulin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(1):95-98
We consider interaction of a single level with a broad, tending to semi-infinite continuum. In an example of two exactly solvable
problems, we show that for time dependent quantum systems the probability of the irreversible transition from a discrete level
to a continuum is strongly inhibited or even completely suppressed by the presence of a discrete adiabatic level near the
continuum edge.
Received 10 October 2002 Published online 4 March 2003
RID="a"
ID="a"e-mail: Alain.Sarfati@lac.u-psud.fr 相似文献
108.
M. K. Pandey R. K. Dubey D. N. Tripathi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(2):275-279
The Classical Trajectory Monte Carlo (CTMC) Method has
been used to calculate the differential, partial and total single electron
capture cross sections for the collision of H+/D+ with Ca and Mg
atoms in the energy range of 1–100 keV. The differential cross sections
at angles near the diffraction limit (<0.1○) in both systems
show a forward peak followed by an asymptotic fall at higher angles. Total
and partial capture cross sections are found to be in good agreement with
the experimental observations. Oscillations in the partial capture cross sections have been explained due to the swapping
of the field electron.
Isotope effect in the electron transfer is reported to be negligible. 相似文献
109.
A Statistical Method for Analysis of Technical Data of a Badminton Match Based on 2-D Seriate Images 总被引:1,自引:0,他引:1
The use of computer vision technology to collect and analyze statistics during badminton matches or training sessions can be expected to provide valuable information to help coaches to determine which tactics should be used by a player in a given game or to improve the player's tactical training. A method based on 2-D seriate images by which statistical data of a badminton match can be obtained is presented. Image capture and analysis were performed synchronously using a multithreading technique. The regions of movement in the images were detected using a temporal difference method, and the trajectories of the movement regions were analyzed using sedate images. The shuttlecock trajectory was extracted from all detected trajectories using various characteristic parameters. The stroke type was determined by comparing the shuttlecock trajectory data with a set of stroke definition data. The algorithm was tested at a training center, and the results were compared with baseline data obtained by expert visual inspection using four video samples, which included approximately 10 000 frames. The shuttlecock trajectory and stroke type were detected correctly in almost 100% of the analyzed video sequences. The average speed of the automated analysis was approximately 40 frames/s, indicating that the method can be used for real-time analysis during a badminton match. The system is convenient for use by a sports coach. 相似文献
110.
针对寒地城市保障性住宅项目的自身特点以及居住主体的心理行为特征,提出了低收入住宅外部空间设计的经济实用性、行为心理适应性以及地域文化适应性的原则,并根据住区外部空间中存在的问题提出了相应的设计策略,以期对保障性住宅项目的开发建设有借鉴意义。 相似文献