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排序方式: 共有1007条查询结果,搜索用时 31 毫秒
51.
Michael J. Murdoch Dragan Sekulovski Ingrid Heynderickx 《Color research and application》2014,39(2):169-178
Preferred chroma enhancement and its dependence on hue are studied in a two‐part experiment using a wide‐gamut multiprimary display. Earlier research showed a clear dependence on hue but was limited by the gamut of the display it employed; the present work builds on this while easing the gamut constraints. In the first part of the present experiment, a tuning task was used to refine the preference for chroma boost starting with standard‐gamut (Rec. 709) images. The overall median preferred boost is roughly 20%, but it is not uniform over hues: the preferred boost for orange, yellow, green, and cyan colors is greater than that for blue, magenta, and red colors. Dependence on image content and observer is noted, though a content‐independent chroma boost created by aggregating preference over many images performs well. An adjustment parameter for overall chroma, which incorporates the hue dependence averaged over image content, should be sufficient to handle the vast majority of interobserver variance in preference. In the second part of the experiment, various chroma boost algorithms were evaluated through a paired comparison task. The prescribed hue‐dependent chroma boost is preferred over all other variations, and all hue‐preserving chroma boost variations are preferred over both colorimetrically accurate and na??ve same‐drive‐signal renderings. The results may be applied in display design to select gamut boundaries that maximize satisfaction over the observer population. © 2012 Wiley Periodicals, Inc. Col Res Appl, 39, 169–178, 2014 相似文献
52.
The most important aim in the design and processing of functionally graded materials (FGMs) is to produce devices free from any deformation. Smart choices of different combination of graded layers, as well as the heating rate during sintering, are important for the fabrication of high-quality FGMs. In this study, BaTi0.975Sn0.025O3/BaTi0.85Sn0.15O3 (noted as BTS2.5 and BTS15, respectively) FGM was used as a model system for the construction of master sintering curves (MSCs) and estimation of the effective activation energies of sintering for different BTS graded layers. The MSCs were constructed, for BTS2.5 and BTS15 graded layers in FGMs, using shrinkage data obtained by a heating microscope during sintering at four constant heating rates, 2, 5, 10 and 20 °/min. The effective activation energies were determined using the concept of MSC; values of 359.5 and 340.5 kJ/mol were obtained for graded layers BTS2.5 and BTS15, respectively. A small difference of the effective activation energies of chosen powders made it possible for us to prepare high-quality FGMs, without delamination, distortion or other forms of defects. 相似文献
53.
Dragan Kandic Branimir Reljin 《International Journal of Circuit Theory and Applications》1994,22(3):163-174
A new class of non-canonic, driving-point immittance realizations of passive, common-ground, transformerless, two-element-kind RLC networks with minimum number of nodes is presented. Six new algorithms of realization are developed by application of canonic, orthogonal matrix transformations with reduced number of degrees of freedom. the number of applied RLC elements of one kind can be minimized and of the other kind reduced, while their parameter values are calculated directly in a linear way. 相似文献
54.
Veljko Potkonjak Jelena Radojicic Spyros Tzafestas Dragan Kostic 《Journal of Intelligent and Robotic Systems》2002,35(4):353-364
This part of the paper examines numerically the possibility of modeling robot fatigue being representative of a human psychophysical state that can be applied to robots. Temperatures of driving motors are suggested as analogs to fatigue in muscles. Simulation of robot behavior is performed on a typical human task, namely handwriting. Three phases of task execution, characteristic for humans, are observed, i.e. regular motion, reconfiguration after symptoms of fatigue, and degeneration caused by the too long, hard work. 相似文献
55.
E. P. Pozhidaev V. G. Chigrinov Yu. P. Bobilev V. M. Shoshin A. A. Zhukov A. L. Andreev I. N. Kompanets Li Xihua E. E. Gukasjan P. S. Komarov O. A. Shadura H. S. Kwok 《Journal of the Society for Information Display》2006,14(7):633-641
Abstract— A passively addressed 64 × 64 ferroelectric liquid‐crystal display (FLCD) has been developed. The display matrix has a 33 × 33 mm2 aperture, and the FLC layer thickness is 5.2 ± 0.2 μm. The display device operates with a frame frequency of 30 Hz (at Vrow = ±18 V, Vcol = ±9 V, T = 23°C), generating a continuous gray scale which can be memorized for more than 10 days after the driving voltage is switched off. A new approach for multiplex electronic addressing of the FLCD gray scale is proposed. The conditions of the hysteresis‐free gray‐scale generation for multiplex addressing and the gray‐scale memorization after the voltage is switched off, as well as the time steadiness of memorized images, are considered. 相似文献
56.
M. M. Sychov E. V. Komarov L. V. Grigor’ev S. V. Myakin I. V. Vasil’eva A. I. Kuznetsov V. P. Usacheva 《Semiconductors》2006,40(9):1016-1020
The effect of γ-ray photons and electron beams on electroluminescence of the ZnS:(Cu, Br) and ZnS:(Cu, Al, Br) phosphors is studied. Irradiation of both samples with γ-ray photons and of the ZnS(Cu, Br) sample with electrons makes it possible to increase the emission intensity by 20–35% at the optimal radiation dose of 5–10 Mrad. In this case, the relative intensity of the green-emission band increases in the electroluminescence spectra of all samples, presumably due to dissociation of the CuI-CuZn and BrZn-V Zn donor-acceptor pairs. Thus, irradiation makes it possible to control the intensity and spectrum of phosphors’ emission, which can be used for nonchemical lithography of luminescent layers. 相似文献
57.
A Genetic Programming Approach to Rainfall-Runoff Modelling 总被引:2,自引:1,他引:1
Planning for sustainable development of water resources relies crucially on the data available. Continuous hydrologic simulation based on conceptual models has proved to be the appropriate tool for studying rainfall-runoff processes and for providing necessary data. In recent years, artificial neural networks have emerged as a novel identification technique for the modelling of hydrological processes. However, they represent their knowledge in terms of a weight matrix that is not accessible to human understanding at present. This paper introduces genetic programming, which is an evolutionary computing method that provides a transparent and structured system identification, to rainfall-runoff modelling. The genetic-programming approach is applied to flow prediction for the Kirkton catchment in Scotland (U.K.). The results obtained are compared to those attained using two optimally calibrated conceptual models and an artificial neural network. Correlations identified using data-driven approaches (genetic programming and neural network) are surprising in their consistency considering the relative size of the models and the number of variables included. These results also compare favourably with the conceptual models. 相似文献
58.
A. D. Andreev V. M. Borzdov A. A. Valiev O. G. Zhevnyak F. F. Komarov 《Journal of Engineering Physics and Thermophysics》1998,71(1):111-114
Based on results of measurement and processing of volt-ampere characteristics as well as linetic modeling of electron transfer
by the Monte Carlo method, the influence of the doping level and the temperature on electron mobility in the n channel of
a silicon MOS field-effect transistor operating in a linear regime is investigated.
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 71, No. 1, pp. 116–119, January–February, 1998. 相似文献
59.
V. P. Komarov 《Journal of Engineering Physics and Thermophysics》1970,19(2):921-923
Results are presented of an experimental investigation of the effect of the temperature factor on the law of heat transfer in turbulent boundary layers.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 19, No.2, pp. 185–189, August, 1970. 相似文献
60.