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71.
An T. Nguyen Wei-Cheng Lai Van Viet Tran Duc Dung Nguyen Hung-Chih Kan 《Energy Materials: Materials Science and Engineering for Energy Systems》2016,11(2):23-29
Specific graphene architectures at the macroscopic scale are paramount for exploring new functions and practical uses of graphene. In this study, macroscopic, freestanding, and tubular graphene (TG) architectures were successfully fabricated through a versatile and robust process based on the annealing of cellulose acetate (CA) on Ni templates. These TG architectures can be obtained as woven tubes with diameters of approximately 50 μm; they possess high graphitic crystallinity, strong electrical conductivity, and favorable corrosion resistance. The effects of processing parameters, such as annealing temperature, annealing time, and amount of CA, on the graphene properties of these architectures were investigated and are discussed in this paper. The graphene properties were characterized through field emission scanning electron microscopy, high-resolution transmission electron microscopy, atomic force microscopy, Raman spectroscopy, four-point probe resistivity, and electrochemical measurements. 相似文献
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Prof. Dr. Božidar Šarler Robert Vertnik Agnieszka Zuzanna Lorbiecka Igor Vušanović Bojan Senčič 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(3):99-107
This paper represents the elements and the use of the upgraded simulation system, developed in the last half decade for ?tore Steel billet caster. The simulation system is used in the context of the state-of-the-art automation and information of the twenty-five year-old three-strand Concast billet continuous caster for dimensions square 140 and 180 mm with the capacity of 160,000 tons/year. The simulation system is used in the off-line and on-line modes. The off-line mode is used in order to set the proper process parameters and to calculate the temperature field, macrosegregation, and grain structure of the strand. It is also used to calculate the changes in the caster design such as the secondary cooling and the position of the SEN. The on-line model is used in automatic casting control system. The paper represents an update of our BHM publication of 2005 (Application of Continous Casting Simulation at ?tore Steel, BHM, Vol. 150, No. 9, 300–306). 相似文献
73.
Lam Vu Phan Sang Le Duy-Dinh Duong Duc Anh Satoh Shin’ichi 《Multimedia Tools and Applications》2017,76(5):7041-7065
Multimedia Tools and Applications - Violent scenes detection (VSD) is a challenging problem because of the heterogeneous content, large variations in video quality, and complex semantic meanings of... 相似文献
74.
Nguyen Thu Ha Nguyen Huu Du Do Duc Thuan 《Mathematics of Control, Signals, and Systems (MCSS)》2016,28(2):13
We shall deal with some problems concerning the stability domains, the spectrum of matrix pairs, the exponential stability and its robustness measure for linear implicit dynamic equations of arbitrary index. First, some characterizations of the stability domains corresponding to a convergent sequence of time scales are derived. Then, we investigate how the spectrum of matrix pairs, the exponential stability and the stability radii for implicit dynamic equations depend on the equation data when the structured perturbations act on both the coefficient of derivative and the right-hand side. 相似文献
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Paul Beaucaire Nicolas Gayton Emmanuel Duc Maurice Lemaire Jean-Yves Dantan 《Computers & Industrial Engineering》2012
The quality level of a mechanism can be evaluated a posteriori after several months by following the number of warranty returns. However, it is more interesting to evaluate a predicted quality level in the design stage: this is one of the aims of statistical tolerance analysis. A possible method consists of computing the defect probability (PD) expressed in ppm. It represents the probability that a functional requirement will not be satisfied in mass production. For assembly reasons, many hyperstatic mechanisms require gaps, which their functional requirements depend on. The defect probability assessment of such mechanisms is not straightforward, and requires advanced numerical methods. This problem particularly interests the VALEO W.S. company, which experiences problems with an assembly containing gaps. This paper proposes an innovative methodology to formulate and compute the defect probability of hyperstatic mechanisms with gaps in two steps. First, a complex feasibility problem is converted into a simpler problem. Then the defect probability is efficiently computed thanks to system reliability methods and the m-dimensional multivariate normal distribution Φm. Finally, a sensitivity analysis is provided to improve the original design. The whole approach is illustrated with an industrial case study, but can be adapted to other similar problems. 相似文献
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