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991.
This paper presents the derivation of the precise relation between the displacement of a light spot on an object's surface and the displacement of its image on the detector in an optical triangulation device, along with applications of the design of triangulation devices. Based on this relation, improved designs of optical triangulation devices, including devices of adjustable configurations, are proposed and discussed. 相似文献
992.
The application of light sectioning to the accurate measurement of a rail cross-section, from a train moving at high speed, is described. The intensity distribution through the thickness of the illuminating light sheet is deliberately graded, allowing the shape of the object to be recovered more accurately by interpolation of the sampled image. Rail profiles are extracted with a definition approximately ten-times better than that of the sampled image. 相似文献
993.
B. G. Bhaskaran 《Queueing Systems》1986,1(1):103-127
Given conditions, which concern the infinitesimal parameters of two birth and death processes, the processes are constructed on the same probability space such that one process is almost surely larger than the other. Application is made to M/M/s queueing systems. Stochastic comparisons of queue length and virtual waiting time in two M/M/s systems are obtained. 相似文献
994.
We propose a dynamic process leading to the Shapley value of TU games or any solution satisfying Inessential Game (IG) and Continuity (CONT), based on a modified version of Hamiache's notion of an associated game.
The authors are very grateful to William Thomson and two anonymous referees for valuable comments which much improve the paper.
They provide better statements and proofs of several major results than the original ones. 相似文献
995.
C.D. Tarantilis C.T. Kiranoudis N.D. Theodorakopoulos 《European Journal of Operational Research》2008
A Web-based ERP system developed for attacking business problems and managing real-world business processes ranging from simple office automation procedures to complicated supply chain planning is presented. The system’s Web-aspect provides significant advantages, as the system is distributed through interoperable, cross-platform and highly pluggable Web-service components. The system involves a powerful workflow engine that manages the entire process event flow within the enterprise increasing efficiency and control at the same time. Business processes, when needed, are controlled by the enterprise quality management system and consequently the ISO directives are accurately followed. A real-world process scheduling system developed for the specific needs of Greek Construction Manufacturing Enterprises is illustrated as a detailed paradigm of the system’s capabilities. The problem was formulated to assign project tasks in form of lots to enterprise resources in order that resources idle time and delays in project preparation time were minimized. The problem was solved by a simple and effective heuristic algorithm. 相似文献
996.
Instantaneous phase shifting arrangement for microsurface profiling of flat surfaces 总被引:1,自引:0,他引:1
Phase shifting interferometry is a well-established technique for non-contact surface profile measurement. Though phase shifting technique has many advantages, it is marred by a few inaccuracies due to the vibration and mechanical movement of the phase shifter itself. Significant amount of work is reported to theoretically compensate these error sources. But for a few works, prominent achievements have not been reported in eliminating these error sources in phase shifting interferometry. In this paper, a novel optical layout, in combination with instantaneous phase shifting interferometry is described. Experiments were carried out with this setup on a super mirror with a λ/20 surface roughness, to demonstrate the validity of the principle. 相似文献
997.
998.
The main purpose of this paper is to study quadric stochastic processes in continuous time. The discrete time case was the subject of earlier investigations by Harry Kesten, S. S. Vallander, and Ju. I. Lubich. 相似文献
999.
We use a mathematical isomorphism between the one-dimensional exclusion process and the two-dimensional stochastic Ising model in the low-temperature limit to describe the typical instantaneous shape of a supercritical droplet. We derive, specifically, the exact asymptotic distribution of the boundaries of a (+1) spin region, confined to Z
+
2
and subjected to a positive magnetic field. In an appropriate scaling, the boundary distribution converges to a deterministic continuum limit.On leave at the EPFL, CH-1015 Lausanne, Switzerland. 相似文献
1000.
A. Isar A. Sandulescu W. Scheid 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,12(1):3-10
By using the Lindblad theory for open quantum systems, an analytical expression of the tunneling probability through an inverted
parabola is obtained. This penetration probability depends on the environment coefficients. It is shown that the tunneling
probability increases with the dissipation and the temperature of the thermal bath.
Received 15 October 1999 and Received in final form 5 January 2000 相似文献