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21.
Abstract— In this paper, a software‐processed edge‐ and level‐adaptive overdrive (SELAO) method, which is a novel overdrive technique that utilizes not only a temporal change of gray levels but also a spatial edge intensity of motion pictures, is proposed. The SELAO method is a software video‐processing technology to improve motion‐picture quality rendered on LCDs more than is possible with a conventional SLAO method without edge‐adaptive overdrive, and it works in real time on commonly used personal computers (PCs).  相似文献   
22.
The amplification characteristics of a high Tm3+ concentration gain-shifted Tm-doped fluoride fibre amplifier (GS-TDFA) have been determined with a high input signal power. This GS-TDFA achieved the highest reported internal power conversion efficiency of 70% with a double pass configuration  相似文献   
23.
The authors describe a planar process for the AlGaAs/GaAs HBTs in which collector vias are buried selectively, even to the base layers, with chemical vapor deposited tungsten (CVD-W) films. By using WF6 /SiH4 chemistry, W could be deposited on Pt films, which were overlapped 50 nm thick on the AuGe-based collector electrodes, without depositing W on the surrounding SiO2 layers. Current gains of planar HBTs with 3.5-μm×3.5-μm emitters were up to 150, for a collector current density of about 2.5×104 A/cm2  相似文献   
24.
On the basis of structural information for the cyclic hexapeptide endothelin (ET) receptor antagonist, TAK-044, a series of thieno[2,3-d]pyrimidine-2,4-dione derivatives bearing a carboxyl group and aromatic rings that were important for receptor binding were designed, synthesized, and evaluated for ET receptor binding affinities and inhibitory activities against ET-induced vasoconstriction. Optimization of each substituent in the thieno[2,3-d]pyrimidine ring led to the discovery of a novel and potent nonpeptide ET receptor antagonist, 6-(4-methoxymethoxyphenyl)-5-methylsulfonylaminomethyl-1-(2- methylthiobenzyl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]p yrimidine-3- acetic acid (32 g), which binded to human ETA and ETB receptor subtypes with affinities (IC50) of 7.6 and 100 nM, respectively. Compound 32 g effectively antagonized ET-induced vasoconstriction and the inhibitory effect mediated by the ETB receptor was more potent than that of bosentan, while the inhibitory effect mediated by the ETA receptor was slightly less potent than that of bosentan.  相似文献   
25.
26.
The proposed plasma lens experiment at the Final focus Test Beam (FFTB) facility of the Stanford Linear Accelerator Center has been approved by the adminstration. The experiment would allow the examination of plasma focusing devices for particle beams in the parameter regime of interest to future high-energy colliders. It is expected to lead to compact plasma lens designs capable of focusing the beam to unprecedented small spot sizes.  相似文献   
27.
The calcium antagonistic and alpha 1-adrenergic receptor blocking activities of monatepil maleate (CAS 103377-41-9, (+/-)-N-(6,11-dihydrodibenzo [b, e] thiepin-11-yl) -4-(4-fluorophenyl)-1-piperazinebutanamide monomaleate, AJ-2615), a novel calcium antagonist, its metabolites and their enantiomers were studied in vitro. Monatepil maleate inhibited calcium-induced contractions of rat thoracic aorta (pA2 = 8.71) and l-phenylephrine-induced contractions of rabbit superior mesenteric artery (IC50 = 56.6 nmol/l). The calcium antagonistic activities of the metabolites of monatepil maleate (AJ-2615-sulfoxide A, AJ-2615-sulfoxide B and AJ-2615-sulfone) were 1/10 of that of monatepil maleate. However, their alpha 1-adrenergic receptor blocking activities were similar to or slightly more potent than that of monatepil maleate. The potencies of the calcium antagonistic activities of monatepil maleate and its enantiomers [(S)-AJ-2615 and (R)-AJ-2615] were in the order of (S)-AJ-2615 > monatepil maleate > (R)-AJ-2615 whereas no difference was observed among them in alpha 1-adrenergic receptor blocking activity. In calcium antagonistic and alpha 1-adrenergic receptor blocking activities, there was no difference between the enantiomers of monatepil maleate metabolites. In conclusion, there was a difference with several times in calcium antagonistic activity between the two enantiomers of monatepil maleate but not in their alpha 1-adrenergic receptor blocking activity.  相似文献   
28.
This paper proposes a wide gamut LCD using locally dimmable four‐primary‐color (4PC) LED backlight. Although the color gamut of LCDs has been improved in recent years, it is insufficient to reproduce all the colors in the real world. The objective of this paper is to propose a wide gamut LCD that reproduces all the colors in the real world while keeping the cost increases to a minimum. We evaluated the color gamut reproduced by LEDs of multiple primary colors and selected cyan as the optimal color to be added to the three primary colors to reproduce all the colors in the real world. Therefore, we designed an LED backlight consisting of an additional only‐cyan LED with three‐primary‐color LEDs and developed a prototype LCD with 4PC LED backlight. Furthermore, we developed a local dimming algorithm for the 4PC LED backlight. As a result, we confirmed that the prototype LCD with the 4PC LED backlight is able to cover almost all the colors in the real world and also able to display natural images with highly saturated colors by local dimming.  相似文献   
29.
Holographic projection is for laser displays and has the merits of being aberration free, producing high‐contrast images, having the ability of color reconstruction with one spatial light modulator, and so on. In this paper, we propose a zoomable holographic projection without using a zoom lens and verify the proposed method by using numerical simulation. Although such a system can be readily realized to use the features of holography, which is capable of recording a large image exceeding the hologram size, the required calculation is very time consuming. For acceleration, we used shifted Fresnel diffraction for setting different sampling rates on a hologram and projected image. The proposed method can project any zoom‐in and zoom‐out image between zeroth‐order and first‐order lights, and the processing time and required memory for the zoom are constant.  相似文献   
30.
Bioactive glass-ceramics toughened by tetragonal zirconia polycrystal (TZP) were prepared by hot-pressing mixed powders of the MgO-CaO-P2O5-SiO2 glass and TZP containing 20 to 80% alumina. The bending strength and the fracture toughness of the composite materials were improved compared with those of the material without TZP. These composites showed high bending strengths (400 to 500MPa) and high fracture toughness ( 2.8MPa m1/2). The existence of a crack deflection mechanism was observed by scanning electron microscopy. After soaking in simulated physiological solution at 100 °C, no phase transformation from tetragonal to monoclinic of TZP in the composites and no degradation in bending strength occurred.  相似文献   
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