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1.
Godfrey C. Onwubolu Petr Buryan Frank Lemke 《The International Journal of Advanced Manufacturing Technology》2008,39(11-12):1080-1092
This paper presents an enhanced approach to predictive modeling for determining tool-wear in end-milling operations based on enhanced-group method of data handling (e-GMDH). Using milling input parameters (speed, feed, and depth-of-cut) and response (tool wear), the data for the model is partitioned into training and testing datasets, and the training dataset is used to realize a predictive model that is a function of the input parameters and the coefficients determined. In our approach, we first present a methodology for modeling, and then develop predictive model(s) of the problem being solved in the form of second-order equations based on the input data and coefficients realized. This approach leads to some generalization because it becomes possible to predict not only the test data obtained during experimentation, but other test data outside the experimental results can also be used. Moreover, this approach makes it easy to present the realized solution in a form that can be further optimized for the input parameters using some optimization techniques. The results realized using our e-GMDH method are promising, and the comparative study presented shows that the e-GMDH outperforms polynomial neural network (PNN); moreover, it is more flexible than the conventional GMDH, which tends to produce nonlinear solutions even for simple problems. In the investigation, the extended particle swarm optimization (PSO) technique was applied to obtain the optimal parameters. Consequently, the modeling approach is extremely useful in realizing a computer-aided process-planning system in an advanced manufacturing environment. 相似文献
2.
3.
Wiltrout Charles; Dogra Samriti; Linster Christiane 《Canadian Metallurgical Quarterly》2003,117(2):236
Studies on odor mixture perception suggest that although odor components can often be identified in mixtures, mixtures can also give rise to novel perceptual qualities that are not present in the components. Using an olfactory habituation task, the authors evaluated how the perceptual similarity between components in a mixture affects the perceptual quality of the mixture itself. Rats perceived binary mixtures composed of similar components as different from their 2 components, whereas binary mixtures composed of dissimilar components were perceived as very similar to their components. Results show that for both types of mixtures, pretraining to Component A reduces subsequent learning about Component B in rats trained in the presence of A. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Randal A.Lemke 《现代音响技术》2004,(7):82-83
我今天很高兴能来到这里与你们一起讨论关于AV通信产业所面临的全球性机遇以及中国AV通信产业如何随着世界市场共同成长的问题。从某种意义上讲,我们所面临的机遇是无限的,因为对于政府、商务、教育和几乎其他所有机构的未来通信基础构造而言,AV通信将是极其关键的。 相似文献
5.
Christiane Bender 《Industry and innovation》1996,3(2):153-162
The Paper develops a critique of industrial restructuring measures from the perspective of social innovation theory. Three kinds of industrial restructure are discussed: business process re-engineering; computer-integrated manufacturing; and lean production. The paper argues that the dominant approaches to these restructuring initiatives are socially deficient in that they do not draw on the full potential of the workforce. 相似文献
6.
Artificial added mass instabilities in sequential staggered coupling of nonlinear structures and incompressible viscous flows 总被引:1,自引:0,他引:1
Christiane Förster Wolfgang A. Wall 《Computer Methods in Applied Mechanics and Engineering》2007,196(7):1278-1293
Within this paper the so-called artificial added mass effect is investigated which is responsible for devastating instabilities within sequentially staggered Fluid-structure Interaction (FSI) simulations where incompressible fluids are considered.A discrete representation of the added mass operator MA is given and ‘instability conditions’ are evaluated for different temporal discretisation schemes. It is proven that for every sequentially staggered scheme and given spatial discretisation of a problem, a mass ratio between fluid and structural mass density can be found at which the coupled system becomes unstable. The analysis is quite general and does not depend upon the particular spatial discretisation schemes used. However here special attention is given to stabilised finite elements employed on the fluid partition. Numerical investigations further highlight the results. 相似文献
7.
We investigate a metric facility location problem in a distributed setting. In this problem, we assume that each point is a client as well as a potential location for a facility and that the opening costs for the facilities and the demands of the clients are uniform. The goal is to open a subset of the input points as facilities such that the accumulated cost for the whole point set, consisting of the opening costs for the facilities and the connection costs for the clients, is minimized. We present a randomized distributed algorithm that computes in expectation an ${\mathcal {O}}(1)$ -approximate solution to the metric facility location problem described above. Our algorithm works in a synchronous message passing model, where each point is an autonomous computational entity that has its own local memory and that communicates with the other entities by message passing. We assume that each entity knows the distance to all the other entities, but does not know any of the other pairwise distances. Our algorithm uses three rounds of all-to-all communication with message sizes bounded to $\mathcal{O}(\log(n))$ bits, where n is the number of input points. We extend our distributed algorithm to constant powers of metric spaces. For a metric exponent ?≥1, we obtain a randomized ${\mathcal {O}}(1)$ -approximation algorithm that uses three rounds of all-to-all communication with message sizes bounded to $\mathcal{O}(\log(n))$ bits. 相似文献
8.
Vera Sheinman Christiane Fellbaum Isaac Julien Peter Schulam Takenobu Tokunaga 《Language Resources and Evaluation》2013,47(3):797-816
We propose a new semantic relation for gradable adjectives in WordNet, which enriches the present, vague, similar relation with information on the degree or intensity with which different adjectives express a shared attribute. Using lexical-semantic patterns, we mine the Web for evidence of the relative strength of adjectives like “large”, “huge” and “gigantic” with respect to their attribute (“size”). The pairwise orderings we derive allow us to construct scales on which the adjectives are located. To represent the intensity relation among gradable adjectives in WordNet, we combine ordered scales with the current WordNet dumbbells based on the relation between a pair of central adjectives and a group of undifferentiated semantically similar adjectives. A new intensity relation links the adjectives in the dumbbells and their concurrent representation on scales. Besides capturing the semantics of gradable adjectives in a way that is both intuitively clear as well as consistent with corpus data, the introduction of an intensity relation would potentially result in several specific benefits for NLP. 相似文献
9.
Christiane Gresse von Wangenheim Marcello Thiry Djone Kochanski 《Empirical Software Engineering》2009,14(4):418-452
Software measurement is considered important in improving the software process. However, teaching software measurement remains
a challenging issue. Although, games and simulations are regarded powerful tools for learning, their learning effectiveness
is not rigorously established. This paper describes the results of an explorative study to investigate the learning effectiveness
of a game prototype on software measurement in order to make an initial judgment about its potential as an educational tool
as well as to analyze its appropriateness, engagement and strengths & weaknesses as guidance for further evolution. Within
the study, a series of experiments was conducted in parallel in three master courses in Brazil. Results of the study reveal
that the participants consider the content and structure of the game appropriate, but no indication for a significant difference
on learning effectiveness could be shown.
相似文献
Djone KochanskiEmail: |
10.
Adaptive echo cancellers are currently being studied for applications such as audio teleconference systems or hands-free telephone sets with high speech quality. The purpose of the echo control is to eliminate the acoustic feedback from the loudspeaker to the microphone. One problem of echo cancellers using e.g. the normalized least mean square algorithm(nlms) for the adaptation of the coefficients is that the convergence properties degrade with colored signal input such as speech signals [8, 9, 17]. One approach to accelerate the convergence speed is to introduce linear prediction filters in order to decorrelate the speech signal [1, 2, 12, 15, 20]. This paper presents a new approach, named the excited lms algorithm orelms algorithm, which prewhitens the input signal applying perfect sequences. Coincidently, the proposed algorithm can be interpreted as a combination of the conventionalnlms algorithm and a system identification approach using m-sequences or related sequences. 相似文献