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51.
A methodology is described for evolving a Rough-fuzzy multi layer perceptron with modular concept using a genetic algorithm to obtain a structured network suitable for both classification and rule extraction. The modular concept, based on "divide and conquer" strategy, provides accelerated training and a compact network suitable for generating a minimum number of rules with high certainty values. The concept of variable mutation operator is introduced for preserving the localized structure of the constituting knowledge-based subnetworks, while they are integrated and evolved. Rough set dependency rules are generated directly from the real valued attribute table containing fuzzy membership values. Two new indices viz., "certainty" and "confusion" in a decision are defined for evaluating quantitatively the quality of rules. The effectiveness of the model and the rule extraction algorithm is extensively demonstrated through experiments alongwith comparisons. 相似文献
52.
T. A. Stoffregen, L. J. Smart, B. G. Bardy, and R. J. Pagulayan (1999) combined a postural task (upright stance) with a suprapostural task (visual fixation) to show that sway variability was not driven by optic flow in a task-independent manner (autonomous control) but governed by the demands of the supra-postural task (facilitatory control). The present study used a novel combination of Stoffregen et al.'s task conditions but obtained clear evidence of autonomous control and no indication of facilitatory control. The theoretical adequacy of the stabilization-by-looking versus stabilization-of-looking contrast was examined, as was emerging evidence that posture control and common cognitive tasks place concurrent demands on the same capacity-limited resources. An adaptive resource-sharing view of postural-suprapostural multitasking was proposed as an alternative to both the autonomous- and facilitatory-control views. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Kumar DD Mitra S Senthil K Sharma DK Rajan RN Sharma A Nagesh KV Chakravarthy DP 《The Review of scientific instruments》2008,79(4):045104
A design approach giving the optimum number of stages in a magnetic pulse compression circuit and gain per stage is given. The limitation on the maximum gain per stage is discussed. The total system volume minimization is done by considering the energy storage capacitor volume and magnetic core volume at each stage. At the end of this paper, the design of a magnetic pulse compression based linear induction accelerator of 200 kV, 5 kA, and 100 ns with a repetition rate of 100 Hz is discussed with its experimental results. 相似文献
54.
AbstractThe time evolution of entanglement between two quantum dots (QDs) trapped inside a cavity driven by a coherent quantized field is studied. In the presence of dissipation, entanglement shows many interesting features such as sudden death and revival, and finite steady state value after sudden death. We also investigate dependence of entanglement on dot variables and its relation to bistability. It is found that entanglement vanishes when the cavity field intensity approaches the upper branch of the bistability curve. When the cavity is driven by a modulated field in the presence of dissipation, it can periodically generate entanglement, which is much larger than the maximum value attained in the steady-state for this system but the dots are never fully entangled. 相似文献
55.
56.
Modak Pranabananda Patra Sudipta Mitra Rahul Chakrabarti Debalay 《Metallurgical and Materials Transactions A》2018,49(6):2219-2234
Metallurgical and Materials Transactions A - Effect of the initial as-cast structure on the microstructure–texture evolution during thermomechanical processing of 409L grade ferritic... 相似文献
57.
Talukder Alam Pavani Kami Lingfei Cao Soumya Nag Colleen Bettles Xinhua Wu Rajarshi Banerjee 《Metallurgical and Materials Transactions A》2014,45(3):1089-1095
The onset of α nucleation in a carbon containing β-titanium alloy has been investigated by coupling atom probe tomography (APT) with transmission electron microscopy. The analysis of the APT results indicates that in addition to ω precipitates that can act as potential α nucleation sites, carbon atoms tend to form clusters within the β-matrix, which in turn give rise to additional nucleation sites for α, resulting in finer scale α precipitates due to increased nucleation density. 相似文献
58.
Abhas Mitra 《Gravitation and Cosmology》2013,19(2):134-137
For the first time, we express the general Friedmann-Robertson-Walker (FRW) metric (k = +1, 0,?1) into explicit “Schwarzschild” or “Curvature” form, which is important from the viewpoint of cosmology. With this form of the FRW metric, we reconsider the old problem of embedding a Schwarzschild mass (SM) in a pre-existing FRW background from the viewpoints of both (1) the enigmatic McVittie metric, obtained in 1933 and (2) the Einstein-Straus approach (1945) of scooping out a spherical cavity in the same background. Since the exterior of the SM is, by definition, described in the Schwarzschild coordinates, for a definitive study of the Einstein-Straus approach we employ this form of the FRW metric. We find that a necessary condition for a SM to participate in the cosmic expansion is that the background fluid is dust. 相似文献
59.
60.
Abhishek Mitra N. Siva Prasad G. D. Janaki Ram 《Journal of Materials Engineering and Performance》2016,25(4):1384-1393
Ferritic steel weldments are invariably post-weld heat treated for relieving the residual stresses. However, the long duration of post-weld heat treatment (PWHT) required for very thick weldments can adversely affect the mechanical properties and fracture toughness. Thus, there is a need to establish the relative importance of temperature and time of PWHT with respect to stress relief. Accordingly, in the present work, the phenomenon of stress relief (due to PWHT) in an 800-mm-thick steel weldment was investigated using finite element analysis and the results were validated against experimental measurements. An analytical study was also carried out to determine the relative influence of temperature and time of PWHT on stress relief. It was found that time of PWHT plays a more significant role in case of relatively lower PWHT temperatures. It was also found that, for a given value of Hollomon parameter, different combinations of PWHT temperature and time can be employed to achieve the same level of stress relief. A mathematical relationship has been established between Hollomon parameter and magnitude of residual stress after PWHT. It has been shown that residual stress is a monotonically decreasing function of the Hollomon parameter. 相似文献