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131.
The conjecture according to which the mean energy of an equilibrium system in quantum theory exceeds the mean energy of the corresponding classical system is considered. It is rigorously proved that the conjecture holds for the potential well. The estimates for the mean energy of the potential well at high and low temperatures are of special interest.  相似文献   
132.
激光除锈过程的实时监测技术研究   总被引:6,自引:1,他引:5  
徐军  孙振永  周文明  翁晓东 《光子学报》2002,31(9):1090-1092
对激光除锈过程中的实时监测技术进行了实验研究,结果表明:除锈过程中产生的声波强度会随着表面清洁度的变化而发生明显的变化,声波信号包含了除锈过程中的大量信息,可作为激光除锈实时监测的基本信号.  相似文献   
133.
An effective residual interaction between particles and holes for shell model calculations around 208Pb, derived from the interaction between free nucleons, is compared with the measured properties of proton-hole neutron states in 208Tl and the interaction between proton holes is adjusted to newly measured level energies in 206Hg. These interaction elements are particularly relevant for neutron-rich nuclei. The adjustment of two mixing elements reproduces the known γ-decay data in 208Tl. Received: 2 April 2002 / Accepted: 2 May 2002  相似文献   
134.
本文介绍一种二级计算机控制的弧焊机器人控制系统。在考虑相邻关节影响的条件下,对弧焊机器人控制系统的硬件电路和控制方法进行了分析和设计.  相似文献   
135.
用气相色谱的分析方法研究了理想非线性单组分不同温度下的流出曲线,用"特征点"法回归出了各组分的物理常数G和b,代入理论模型公式,并与实验结果进行子比较。  相似文献   
136.
van der Mei  R.D.  Levy  H. 《Queueing Systems》1997,27(3-4):227-250
We study the expected delay in cyclic polling models with general ‘branching-type’ service disciplines. For this class of models, which contains models with exhaustive and gated service as special cases, we obtain closed-form expressions for the expected delay under standard heavy-traffic scalings. We identify a single parameter associated with the service discipline at each queue, which we call the ‘exhaustiveness’. We show that the scaled expected delay figures depend on the service policies at the queues only through the exhaustiveness of each of the service disciplines. This implies that the influence of different service disciplines, but with the same exhaustiveness, on the expected delays at the queues becomes the same when the system reaches saturation. This observation leads to a new classification of the service disciplines. In addition, we show monotonicity of the scaled expected delays with respect to the exhaustiveness of the service disciplines. This induces a complete ordering in terms of efficiency of the service disciplines. The results also lead to new rules for optimization of the system performance with respect to the service disciplines at the queues. Further, the exact asymptotic results suggest simple expected waiting-time approximations for polling models in heavy traffic. Numerical experiments show that the accuracy of the approximations is excellent for practical heavy-traffic scenarios. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
137.
This paper describes a method and the corresponding algorithms for simplification of large-scale linear programming models. It consists of the elimination of the balance constraints (i.e. constraints with zero RHS term). The idea is to apply some linear transformations to the original problem in order to nullify the balance constraints. These transformations are able to simultaneously eliminate more balance rows. The core of this contribution is the introduction of the reduction matrix and the associated theorems on the equivalent linear programs (original and reduced). The numerical experiments with this method of simplification proved this approach to be beneficial for a large class of LP problems.This research work was done while the first author was at Duisburg University, Mess-, Steuer und Regelungstechnik, Germany, under the greatly appreciated financial assistance given by the Alexander-von-Humboldt Foundation.  相似文献   
138.
本文采用不同于文献[8]的方法,研究了非线性非完整保守系统的稳定性问题,并给出了相应的稳定准则  相似文献   
139.
本文以一座大型厂矿文化宫建筑设计实例,扼要论述了多功能厅堂的设计要点,结合我国目前多功能厅堂使用状况,提出以电声为主的设计原则和实施办法,以改善多功能厅堂的音质效果。  相似文献   
140.
Coulomb systems in which the particles interact through thed-dimensional Coulomb potential but are confined in a flat manifold of dimensiond–1 are considered. The actual Coulomb potential acting is defined by particular boundary conditions involving a characteristic macroscopic distanceW in the direction perpendicular to the manifold: either it is periodic of periodW in that direction, or it vanishes on one ideal conductor wall parallel to the manifold at a distanceW from it, or it vanishes on two parallel walls at a distanceW from each other with the manifold equidistant from them. Under the assumptions that classical equilibrium statistical mechanics is applicable and that the system has the macroscopic properties of a conductor, it is shown that the suitably smoothed charge correlation function is universal, and that the free energy and the grand potential have universal dependences onW (universal means independent of the microscopic detail). The casesd=2 are discussed in detail, and the generic results are checked on an exactly solvable model. The cased=3 of a plane parallel to an ideal conductor is also explicitly worked out.Laboratoire associé au Centre National de la Recherche Scientifique-URA D0063.  相似文献   
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