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排序方式: 共有2326条查询结果,搜索用时 15 毫秒
31.
Moon Sam Shin Ki-Pung Yoo Chul Soo Lee Hwayong Kim 《Korean Journal of Chemical Engineering》2006,23(3):469-475
A multi-fluid nonrandom lattice fluid model with no temperature dependence of close packed volumes of a mer, segment numbers
and energy parameters of pure systems is presented. The multi-fluid nonrandom lattice fluid (MF-NLF) model with the local
composition concept was capable of describing properties for complex systems. However, the MF-NLF model has strong temperature
dependence of energy parameters and segment numbers of pure systems; thus empirical correlations as functions of temperature
were represented for reliable and convenient use in engineering practices. The MF-NLF model without temperature dependence
of pure parameters could not predict thermodynamic properties accurately. It was found that the present model with three parameters
describes quantitatively the vapor pressure and the saturated density for the pure fluid. 相似文献
32.
Software and Systems Modeling - Advances in model-based system engineering have greatly increased the predictive power of models and the analyses that can be run on them. At the same time, designs... 相似文献
33.
34.
Sibang Liu Shuzhi Sam Ge Zhongliang Tang 《International Journal of Control, Automation and Systems》2016,14(4):924-938
This paper presents a modular designed autonomous bolt tightening shaft system with an adaptive fuzzy backstepping control approach developed for it. The bolt tightening shaft is designed for the autonomous bolt tightening operation, which has huge potential for industry application. Due to the inherent nonlinear and uncertain properties, the bolt tightening shaft and the bolt tightening process are mathematically modeled as an uncertain strict feedback system. With the adaptive backstepping and approximation property of fuzzy logic system, the controller is recursively designed. Based on the Lyapunov stability theorem, all signals in the closed-loop system are proved to be uniformly ultimately bounded and the torque tracking error exponentially converges to a small residue. And the effectiveness and performance of the proposed autonomous system are verified by the simulation and experiment results on the bolt tightening shaft system. 相似文献
35.
36.
Sam Dong Jung Jeong Soo Kim Jung Won Park Jong Hwa Won Moon Kyum Kim 《Multimedia Tools and Applications》2015,74(20):9017-9029
A technique is developed to clearly establish the shear resistance of a cellular structure, retaining wall composed of a steel frame and fill materials with both continuous and discontinuous characteristics. To overcome the limitation of the existing analysis approach based on continuum mechanics, in which the shear behavior and interaction between the frames and fill material of this type of structure are difficult to describe, this paper introduces displacement incremental analysis into the distinct element method. The results obtained by using the proposed approach are compared with experimental results to verify its accuracy. The results show an internal friction angle of fill materials and overburdening load are major factor determining the shear resistance of a retaining wall with a cellular structure type. From the results of the parametric study on the shear behavior of this type of structure, this paper also proposes a shear resistance moment-shear displacement formula for designing a retaining wall with a cellular structure type. 相似文献
37.
在国内的汽车隔音市场上.安博士无疑是最勤奋.也最具创新精神的品牌了,其独辟蹊径推出的专车专用隔音概念.不仅赢得了市场上的一致好评.而且也获得了消费者的认可。 相似文献
38.
Richmond VL Rayson MP Wilkinson DM Carter JM Blacker SD Nevill A Ross JD Moore S 《Ergonomics》2008,51(6):935-946
Since 2002, the Royal Air Force (RAF) has been working towards developing role-related physical tests for use as an operational fitness test (OFT). The purpose of this study was to establish reliability of the OFT (comprising four tests), investigate gym-based tests as predictors of performance and establish performance standards. Fifty-eight RAF personnel performed the OFT on three occasions. A separate cohort carried out fitness and anthropometric tests before performing the OFT, by way of establishing performance predictors. Documented evidence and views of an expert panel were used to determine OFT standards. Reliability ranged from moderate to good for three tests, with one test (Dig) showing poor reliability. The 95% limits of agreement for the prediction models ranged from good to poor (6.7-34.2%). The prediction models were not sufficiently accurate to estimate confidently OFT performance, but could be used as a guide to quantify likely outcome and training needs. 相似文献
39.
This paper describes a novel feature selection algorithm for unsupervised clustering, that combines the clustering ensembles method and the population based incremental learning algorithm. The main idea of the proposed unsupervised feature selection algorithm is to search for a subset of all features such that the clustering algorithm trained on this feature subset can achieve the most similar clustering solution to the one obtained by an ensemble learning algorithm. In particular, a clustering solution is firstly achieved by a clustering ensembles method, then the population based incremental learning algorithm is adopted to find the feature subset that best fits the obtained clustering solution. One advantage of the proposed unsupervised feature selection algorithm is that it is dimensionality-unbiased. In addition, the proposed unsupervised feature selection algorithm leverages the consensus across multiple clustering solutions. Experimental results on several real data sets demonstrate that the proposed unsupervised feature selection algorithm is often able to obtain a better feature subset when compared with other existing unsupervised feature selection algorithms. 相似文献
40.
Many existing systems are written in C and are not re‐entrant or thread safe. Sometimes these systems are required in a context for which they were not first designed, possibly meaning they now need to be re‐entrant. This article introduces a program that filters C source code, modifying shared resources (the global variables) to make the code re‐entrant: ‘virtualizing’ the code. The code is then compiled as normal. This approach allows programmatic virtualization with little cost at runtime. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献