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991.
Any truncated-path-integral partition function of a nonrelativistic quantum system in thermodynamic equilibrium—one obtained by means of the Feynman path-integral-procedure using a finite number of such integrals—is known to have a value not less than that of the exact one corresponding to it. A rigorous asymptotic lower bound obtained for the relative disparity in their values—the difference in their values divided by that of the exact partition function— confirms asymptotic positive-definiteness of the original upper bound. Values determined directly for a linear harmonic oscillator agree asymptotically with values of they bound. 相似文献
992.
$$O\sqrt{n}L$$ ); otherwise, the complexity bound is O(nL). The relations between our search direction and the one used in the standard interior-point algorithm are also discussed.
Received September 9, 1996 / Revised version received December 22, 1997? Published online March 16, 1999 相似文献
993.
Xiang-fei Chen Sai Hu Yi Luo 《International Journal of Infrared and Millimeter Waves》2000,21(6):939-944
There are multiple passbands in a chirped Bragg grating based on acousto-optic superlattice. The structure can be regarded as an acousto-induced super Moiré grating (AI-SMG). The analysis shows that the passbands of the AI-SMG are produced by several pairs of neighboring chirped gratings. With suitable structure parameters selected, the passbands can be non-larenzian-shape, narrow flat-top, with ripple less than 0.5dB and steep slope. The devices can be used as tunable narrow-band multichannel transmission filters. This analysis is useful for the designs and applications of the devices. 相似文献
994.
A simple general approach to the construction of measures on path space is developed. It is used for the path integral representation of evolutionary equations including Feller processes, the Schro¨dinger equation, and dissipative Schro¨dinger equations. At the end of the paper we give a short guide to the immense literature on path integration sketching the main known approaches to the construction of the Feynman integral and indicating possible generalizations. 相似文献
995.
Kalman filters are widely used in the turbine engine community for health monitoring purpose. This algorithm has proven its capability to track gradual deterioration with a good accuracy. On the other hand, its response to rapid deterioration is either a long delay in recognising the fault, and/or a spread of the estimated fault in several components. The main reason of this deficiency lies in the transition model of the parameters that assumes a smooth evolution of the engine’s condition. The aim of this contribution is to compare two adaptive diagnosis tools that combine a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements on one hand a covariance matching scheme and on the other hand a generalised likelihood ratio test to improve the behaviour of the diagnosis tool with respect to abrupt faults. 相似文献
996.
Due to recent advances in passive acoustic monitoring techniques, beaked whales are now more effectively detected acoustically than visually during vessel-based (e.g. line-transect) surveys. Beaked whales signals can be discriminated from those of other cetaceans by the unique characteristics of their echolocation clicks (e.g. duration >175 μs, center frequencies between 30 and 40 kHz, inter-click intervals between 0.2 and 0.4 s and frequency upsweeps). Furthermore, these same characteristics make these signals ideal candidates for testing automated detection and classification algorithms. There are several different beaked whale automated detectors currently available for use. However, no comparative analysis of detectors exists. Therefore, comparison between studies and datasets is difficult. The purpose of this study was to test, validate, and compare algorithms for detection of beaked whales in acoustic line-transect survey data. Six different detection algorithms (XBAT, Ishmael, PAMGUARD, ERMA, GMM and FMCD) were evaluated and compared. Detection trials were run on three sample days of towed-hydrophone array recordings collected by NOAA Southwest Fisheries Science Center (SWFSC) during which were confirmed visual sightings of beaked whales (Ziphius cavirostris and Mesoplodon peruvianus). Detections also were compared to human verified acoustic detections for a subset of these data. In order to measure the probabilities of false detection, each detector was also run on three sample recordings containing clicks from another species: Risso’s dolphin (Grampus griseus). Qualitative and quantitative comparisons and the detection performance of the different algorithms are discussed. 相似文献
997.
For industrialised economy of ourdays, remanufacturing represents perhaps the largest unexploited resource and opportunity
for realising a greater growth of the economy in an environmental-conscious manner. The aim of this paper is to investigate
of the impact of remanufacturing in the economy from an economic-efficiency point of view. In static context this phenomenon
was analysed in the literature. We use the multi-sector input–output framework in a dynamic context to study intra-period
relationships of the sectors of economy. We extend the classical dynamic input–output model taking into consideration the
activity of remanufacturing .We try to answer the question, whether the remanufacturing/reuse increases the growth possibility
of an economy. We expose a sufficient condition concerning the effectivity of an economy with remanufacturing. By this evaluation
we analyse a possible sustainable development of the economy on the basis of the product recovery management of industries. 相似文献
998.
Carsten Thomassen 《Journal of Graph Theory》2008,58(4):286-292
We prove that a 171‐edge‐connected graph has an edge‐decomposition into paths of length 3 if and only its size is divisible by 3. It is a long‐standing problem whether 2‐edge‐connectedness is sufficient for planar triangle‐free graphs, and whether 3‐edge‐connectedness suffices for graphs in general. © 2008 Wiley Periodicals, Inc. J Graph Theory 58: 286–292, 2008 相似文献
999.
图的{P4}——分解 总被引:1,自引:0,他引:1
一个图G的路分解是指一路集合使得G的每条边恰好出现在其中一条路上.记Pl长度为l-1的路,如果G能够分解成若干个Pl,则称G存在{Pl}——分解,关于图的给定长路分解问题主要结果有:(i)连通图G存在{P3}-分解当且仅当G有偶数条边(见[1]);(ii)连通图G存在{P3,P4}-分解当且仅当G不是C3和奇树,这里C3的长度为3的圈而奇树是所有顶点皆度数为奇数的树(见[3]).本文讨论了3正则图的{P4}--分解情况,并构造证明了边数为3k(k∈Z且k≥2)的完全图Kn和完全二部图Kr,s存在{P4}-分解. 相似文献