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81.
Aishwarya Srivastava Siddhant Aggarwal Amy Apon Edward Duffy Ken Kennedy Andre Luckow Brandon Posey Marcin Ziolkowski 《Software》2020,50(6):868-898
We investigate the challenges of building an end-to-end cloud pipeline for real-time intelligent visual inspection system for use in automotive manufacturing. Current methods of visual detection in automotive assembly are highly labor intensive, and thus prone to errors. An automated process is sought that can operate within the real-time constraints of the assembly line and can reduce errors. Components of the cloud pipeline include capture of a large set of high-definition images from a camera setup at the assembly location, transfer and storage of the images as needed, execution of object detection, and notification to a human operator when a fault is detected. The end-to-end execution must complete within a fixed time frame before the next car arrives in the assembly line. In this article, we report the design, development, and experimental evaluation of the tradeoffs of performance, accuracy, and scalability for a cloud system. 相似文献
82.
Cognitive load varies the attention level, which has serious consequences in complex dynamic situations. Assessment of uncertainty in cognitive load during multiple object tracking task is necessary, as it is used to improve the cognitive capabilities. The present research work investigates the uncertainty in cognitive load of multiple object tracking task using electroencephalograph (EEG) on 25 football players. A d2 test of neuropsychological measure of attention was employed before starting the experiment. Each player participated in four levels of the task with variation in the cognitive load, which varies in terms of the targets from 2 to 5. Percentage changes in the power spectral density were estimated for the cognitive levels. Results show that the percentage changes were much more in high cognitive load than in low cognitive load. Significant changes (p < 0.05) were observed in level 1 (− 11.07 to 1.91%), level 2 (− 3.13 to − 14.51%), level 3 (− 6.33 to − 19.46%) and level 4 (− 8.10 to − 20.88%). Variation in the EEG data in terms of the combined uncertainty corresponds very well with low to high cognitive loads. The fourth level of the task with high cognitive load has more uncertainty than the low cognitive load levels. The results are useful for assessing the cognitive state of the player, which is valuable for the design of the effective training model. 相似文献
83.
Zirconia-mullite composites were prepared byin situ reaction between zircon and alumina. Stabilizers like yttria and magnesium carbonate were used. Almost vitrified bodies were
obtained by sintering at 1465–1535°C. Flexural strength increased on annealing at 1040°C. 相似文献
84.
Tanu Sharma Sanjeev Aggarwal Shyam Kumar V. K. Mittal P. C. Kalsi V. K. Manchanda 《Journal of Materials Science》2007,42(4):1127-1130
The UV-Visible absorption spectra of virgin and gamma irradiated (20–800 kGy) CR-39 polymer have been deduced by using Shimadzu
Double beam Double Monochromator UV-Visible Spectrophotometer (UV-2550). The existence of the peaks, their shifting and broadening
as a result of gamma irradiation has been discussed. Finally the indirect and direct band gap in virgin and gamma irradiated
CR-39 has been determined. The values of indirect band gap have been found to be lower than the corresponding values of direct
band gap. 相似文献
85.
Anu Bajaj Atul Khanna Narendra K. Kulkarni Suresh K. Aggarwal 《Journal of the American Ceramic Society》2009,92(5):1036-1041
Bismuth borate glasses from the system: 40Bi2 O3 –59B2 O3 –1Tv2 O3 (where Tv=Al, Y, Nd, Sm, and Eu) and three glasses of composition: 40Bi2 O3 –60B2 O3 , 37.5Bi2 O3 –62.5B2 O3 and 38Bi2 O3 –60B2 O3 –2Al2 O3 were prepared by melt quenching and characterized by density, UV-visible absorption spectroscopy and differential thermal analysis (DTA) studies. Bismuth borate glasses exhibit a very strong optical absorption band just below their absorption edge. Glasses were devitrified by heat treatment at temperatures above their glass transition temperatures and the crystalline phases produced in them were characterized by Fourier transform infrared (FTIR) absorption spectroscopy and X-ray diffraction (XRD). Bi3 B5 O12 was found to be the most abundant phase in all devitrified samples. DTA studies on glasses and FTIR and XRD analysis on crystallized samples revealed that very small amounts of trivalent ion doping causes significant changes in the devitrification properties of bismuth borate glasses; rare-earth ions promote the formation of metastable BiBO3 –I and BiBO3 –II phases during glass crystallization. 相似文献
86.
Mining associations with the collective strength approach 总被引:1,自引:0,他引:1
The large itemset model has been proposed in the literature for finding associations in a large database of sales transactions. A different method for evaluating and finding itemsets referred to as strongly collective itemsets is proposed. We propose a criterion stressing the importance of the actual correlation of the items with one another rather than their absolute level of presence. Previous techniques for finding correlated itemsets are not necessarily applicable to very large databases. We provide an algorithm which provides very good computational efficiency, while maintaining statistical robustness. The fact that this algorithm relies on relative measures rather than absolute measures such as support also implies that the method can be applied to find association rules in data sets in which items may appear in a sizeable percentage of the transactions (dense data sets), data sets in which the items have varying density, or even negative association rules 相似文献
87.
Theoretical and experimental study of the second-order polarizabilities of Schiff''s bases for nonlinear optical applications 总被引:1,自引:0,他引:1
K. Bhat J. Choi S.D. McCall M.D. Aggarwal B.H. Cardelino C.E. Moore Benjamin G. Penn D.O. Frazier M. Sanghadasa T.A. Barr N.B. Laxmeshwar 《Computational Materials Science》1997,8(4):309-316
A series of twenty-four Schiff's bases was synthesized and nonresonant static molecular second order polarizabilities (β) of these compounds were theoretically calculated and compared with experimental values. The computational method employed obtained: (a) values of polarization versus static electric fields using a semiempirical Hamiltonian; (b) all tensor elements of β by performing polynomial fits of the former data, within the finite-field approach. The experimental values were obtained using a modified electric field induced second harmonic generation (EFISH) experiment with 1,4-dioxane as the solvent. The measured quantities were the projection of β on μ (the permanent dipole moment), relative to MNA (2-methyl-4-nitroaniline). The correlation between the predicted static molecular quantities and their corresponding experimental values was 0.95 (based on a simple least-squares regression forced through the origin). A factor of 8.7 ± 0.3 was determined to be the adjustment parameter for Schiff's bases to account for the solvent and dispersion effects at the fundamental wavelength of 1064 nm. 相似文献
88.
89.
Using the methods of recombination and gene disruption, the effects of degUS gene in Bacillus subtilis Ki-2-132 were studied. The results showed that the gene could affect all protease-producing, competence formation, cell mobility and repression effects of glucose on protease-production. This implies that it is a pleitropic gene in Bacillus subtilis Ki-2-132. The disruption of the gene caused morphological changes and repressed the expression of aprE in vectors. 相似文献
90.
Al2O3-ZrO2 composites were prepared in two compositional ranges, 15 wt% ZrO2 and 29wt% ZrO2 with or without yttria or magnesia stabilizers. While 1.5 wt% Y2O3 produced tetragonal ZrO2 and fine grain microstructure, the 4.5 wt% Y2O3 developed cubic and tetragonal ZrO2 with similar microstructure. Al2O3 with 29.5wt% ZrO2-1.5wt% Y2O3 composition had the highest strength (3,300 kg/cm2). The bending strength remained more or less the same after the first thermal shock, and then it decreased gradually, but retained some strength after 20 cycles of quench. The load vs displacement curve became nonlinear after thermal shock possibly because of formation of microcracks which could be seen by microstructural studies. 相似文献