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431.
A simple multilevel halftoning method, which is based on the conventional error diffusion method and realizes halftoning excelled in the distribution of dots, is proposed. The proposed method consists of three steps, e.g., the image decomposition, the generation of binary halftone images by the error diffusion, and the synthesis of a multilevel halftone image, and each step does not require a complicated algorithm. The effectiveness of the proposed method is indicated by applying it to three- and four-level halftoning of gray-tone and natural images. 相似文献
432.
Yusuke Morita Ai Suzuki Michihisa Koyama Nozomu Hatakeyama Hiromitsu Takaba Carlos A. Del Carpio Noriaki Nishino Akira Miyamoto 《Applied Surface Science》2008,254(23):7618-7621
Recently we have developed a novel molecular dynamics program NEW-RYUDO-CR, which can deal with chemical reactions. The developed method has been applied to the study of tribochemical reaction dynamics of MoS2 tribofilm on iron surface. The initially amorphous MoS2 layer self-organized its structure as result of the tribochemical reactions and formed layered MoS2 tribofilm. The friction coefficient significantly decreased as the MoS2 tribofilm was formed. Besides, sliding was observed between sulfur layers of MoS2 tribofilms which occurred due to repulsive Coulombic interaction forces between sulfur atoms. This indicates that the formation of the layered MoS2 tribofilm is important to achieve better lubrication properties. 相似文献
433.
In multimedia content, colors play important roles in conveying visual information. However, color information cannot always
be perceived uniformly by all people. People with a color vision deficiency, such as dichromacy, cannot recognize and distinguish
certain color combinations. In this paper, an effective lightness modification method, which enables barrier-free color vision
for people with dichromacy, especially protanopia or deuteranopia, while preserving the color information in the original
image for people with standard color vision, is proposed. In the proposed method, an optimization problem concerning lightness
components is first defined by considering color differences in an input image. Then a perceptible and comprehensible color
image for both protanopes and viewers with no color vision deficiency or both deuteranopes and viewers with no color vision
deficiency is obtained by solving the optimization problem. Through experiments, the effectiveness of the proposed method
is illustrated. 相似文献
434.
Jan Pejchal Martin Nikl Kentaro Fukuda Noriaki Kawaguchi Takayuki Yanagida Yuui Yokota Akira Yoshikawa Vladimir Babin 《Radiation measurements》2010,45(3-6):265-267
Doubly doped BaY2F8:Er,Nd scintillation crystals were grown by modified micro-pulling-down method. The Er co-doping was chosen to enhance the energy transfer from the host lattice to the Nd3+ luminescence center via the 5d-levels of Er3+, which can be enabled by the overlap of Er3+ 5d-4f emission spectrum with the Nd3+ 4f-5d absorption. The energy transfer was clearly evidenced in the BaY2F8:Er,Nd. The processes are complicated by energy migration to killer centres and/or cross-relaxation processes. The luminescence and energy transfer mechanism are discussed. 相似文献
435.
436.
Kenji Hayashi Minoru Hirayama Taizo Muta Noriaki Seto Takeshi Shirafuji 《Fortschritte der Physik》1967,15(10):625-660
A review is given of recent developments in compositeness arguments of particles in the framework of Lagrangian field theory and S-matrix theory. 相似文献
437.
Optical Review - Recently, smartphone cameras have been increasingly used to take pictures of documents. When a shadow appears in the captured document image, it causes problems such as reduced... 相似文献
438.
Akiya Ogawa Noriaki Takami Masahito Sekiguchi Noboru Sonoda Toshikazu Hirao 《Heteroatom Chemistry》1998,9(6):581-584
Elemental sulfur can be reduced to the corresponding thiolate anion species (S2− and S2−2) selectively by samarium diiodide in the presence and absence of HMPA, respectively. The subsequent alkylation of the thiolate anion species provides a useful synthetic route to dialkyl sulfides and disulfides. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9: 581–584, 1998 相似文献
439.
Toshifumi Satoh Tomoko Imai Yoshikazu Kitajyo Takahiro Maeda Atsushi Narumi Harumi Kaga Noriaki Kaneko Toyoji Kakuchi 《Macromolecular Symposia》2004,217(1):39-46
The thermally induced cationic polymerizations of 1,6-anhydro-β-D -glucopyranose ( 1a ), 1,6-anhydro-β-D -mannopyranose ( 1b ) and 1,6-anhydro-β-D -galactopyranose ( 1c ) as a latent cyclic AB4-type monomer were carried out using (S-2-butenyl)tetramethylenesulfonium hexafluoroantimonate ( 2 ) as an initiator. The solution polymerization in propylene carbonate proceeded without gelation to produce the water-soluble hyperbranched polysaccharides ( 3a-c ) with controlled molecular weights and narrow polydispersities. The degree of branching (DB), estimated by the methylation analysis of 3a-c , was in the range of 0.38 – 0.49. The thermally induced cationic polymerization of 1a-c using 2 is a facile method leading to a hyperbranched polysaccharide with a high DB value. 相似文献