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31.
Abstract— To understand actual viewing conditions at home is important for TV design. And the preferred luminance level of LCD TVs under actual viewing conditions is also important in order to obtain both good picture quality and low power consumption. The actual viewing conditions of households and the preferred luminance levels was investigated. In a field test of 83 households, the display luminance, screen illuminance, and viewing locations were measured on site. In laboratory experiments, young and elderly subjects adjusted the luminance of an LCD‐TV screen to their preferred levels under different screen illuminance levels, angular screen sizes, and average luminance levels (ALL) of the images. As a result, two equations, which represent the preferred luminance level of LCD‐TV screens corresponding to different viewing conditions for young and elderly subjects were obtained. When the ALL of the images was 25% and the screen illuminance and angular screen size were set at 100 lx and 20°, respectively, the preferred luminance was 1 60 cd/m2 for the young subjects and 248 cd/m2 for the elderly subjects. By using the setting of the preferred luminance of an LCD TV under actual viewing conditions, it is possible to conserve energy consumption.  相似文献   
32.
In this paper, the effects of actual environmental actions on shrinkage, creep and shrinkage cracking of concrete are studied comprehensively. Prismatic specimens of plain concrete were exposed to three sets of artificial outdoor conditions with or without solar radiation and rain to examine the shrinkage. For the purpose of studying shrinkage cracking behavior, prismatic concrete specimens with reinforcing steel were also subjected to the above conditions at the same time. The shrinkage behavior is described focusing on the effects of solar radiation and rain based on the moisture loss. The significant environment actions to induce shrinkage cracks are investigated from viewpoints of the amount of the shrinkage and the tensile strength. Finally, specific compressive creep behavior according to solar radiation and rainfall is discussed. It is found that rain can greatly inhibit the progresses of concrete shrinkage and creep while solar radiation is likely to promote shrinkage cracking and creep.  相似文献   
33.
A continuous‐flow reaction system was developed, allowing flow conditions of the entire system to be maintained at a predetermined constant level, which is one of the most significant factors for successful industrial application. Controlled/living anionic polymerization was selected as a model reaction since the characteristics of its polymer products, molecular weights, and molecular weight distributions are highly susceptible to changes in the relative flow rates of a monomer and initiator solutions. In flow microreactors, controlled/living anionic polymerization of styrene in tetrahydrofuran (THF)/hexane initiated by THF‐diluted n‐butyllithium (n‐BuLi) was examined. Poly(styrenes) of larger molecule sizes such as Mn > 15 000 were successfully synthesized. After continuous operation for four hours, ca. 0.5 kg of the polymer was readily produced with narrow molecular weight distribution, demonstrating the applicability of this continuous‐flow system for controlled/living anionic polymerization on considerably large scale with a view to its industrial usage in the future.  相似文献   
34.
We fabricated Sr and Ca-doped CuAlO2 compacts from the mixed powder of CuO, Cu2O, Al2O3, and SrO or CaO by multi-pass hot pressing followed by spark plasma sintering (SPS). The XRD results showed the reaction of CuO, Cu2O and Al2O3 was rather complete and only CuAlO2 single phase was formed when the additive amount of SrO or CaO was appropriate. Multi-pass hot pressing increased the relative density and the usage of plate-like Al2O3 as reaction raw material enhanced the orientation degree. In spite of performance improvement conflicts through elemental doping, density increase and orientation improvement, the measurement on the thermoelectric performance indicated that the electrical resistivity, Seebeck coefficient, power factor, dimensionless figure of merit (ZT) were improved to varying degrees through the synergetic action of elemental doping, density increase, and orientation control. The highest power factor and ZT of the Ca-doped CuAlO2 compacts reached 1.54?×?10?4 W?m?1 K?2 and 0.015 at 973?K, respectively. The thermoelectric performance was higher than those of CuAlO2 at the same temperature in published work before.  相似文献   
35.
Nano-sized gold particles were prepared in a solution containing polyethylenimine (PEI) utilizing a batch reactor. PEI acts as a reducing agent as well as a stabilizing agent of nanoparticles. The effects of initial concentration of PEI on the mean particle diameter, coefficient of variation (C.V.), growth rate, nucleation rate and the number of nuclei were studied. The particle diameter of gold decreased markedly with increasing initial concentration of PEI, from 3.3 μm to a minimum value of about 5 nm. The observed decrease of particle diameter was considered to be caused by the growth-inhibiting effect of PEI, which affects the conclusive number of nuclei.  相似文献   
36.
Temperature-sensitive hydrogel beads were prepared by Kenics static mixer technology. The temperature-sensitive monomer N,N-diethylacrylamide and photo-crosslinkable pre-polymer ENT were used as model hydrogel materials. Drop dispersion of high viscosity polymer material in low viscosity hexadecane was made using the static mixer. Drops of a solution of the mixed materials were rapidly photo-crosslinked by UV irradiation after mixing in the static mixer, and spherical hydrogel beads with narrow, normal size distribution were thus prepared. The Kenics static mixer is a useful device for the preparation of spherical beads of temperature-sensitive hydrogels. The Sauter Mean Diameter of the hydrogel beads swollen in deionized water at 293 K was measured. The experimentally determined dimensionless swollen hydrogel bead diameter was well correlated with the Weber number, degree of swelling and viscosity ratio. The effects of gelation and ENT addition on the bead size were evaluated from the degree of swelling. The correlation equation can be used for size adjustment of temperature-sensitive spherical hydrogel beads.  相似文献   
37.
This paper reports a noninvasive method for evaluating skin aging based on near-infrared diffuse reflectance (NIR-DR) spectroscopy. Skin aging can be attributed to photoaging and chronological aging. Both types of aging are heavily involved in the skin changes that occur as we get older, for example, wrinkles or sagging skin. Our goal is to develop a noninvasive way to assess changes taking place inside the skin for each type of aging by using NIR-DR spectroscopy. Interior skin damages caused by photoaging and chronological aging were studied for an ultraviolet-B (UVB)-irradiated hairless mouse group (24 mice) and a non-irradiated group (29 mice) by using NIR-DR spectroscopy and principal component analysis (PCA). The results suggested the possibility of monitoring the contribution and the quantitative assessment of both types of aging taking place inside the skin by using the 5990-5490 cm(-1) and 5000-4480 cm(-1) regions of NIR-DR spectra. For the photoaging, structural changes in proteins are most clearly reflected by a shift of the band near 4880 cm(-1) due to a combination of amide A and amide II modes. On the other hand, the chronological aging is associated with a change in collagen quantity as is seen in the intensity changes in NIR bands assigned to collagen. NIR-DR spectroscopy and PCA may allow us to noninvasively assess the degree of photoaging and chronological aging as the degeneration of elasticity in collagen protein and the degradation of protein quantity, respectively.  相似文献   
38.
An application of Query-By-Example (QBE) is presented where shots that are visually similar to provided example shots are retrieved. To implement QBE, counter-example shots are required to accurately distinguish shots that are relevant to the query from those that are not (Li and Snoek (2009), Yu et al. (2004)). However, there are usually a huge number of shots, not relevant to a particular query, which can serve as counter-example shots. It is difficult for a user to provide counter-example shots that would aid retrieval. Thus, we developed a QBE method based on partially supervised learning where a retrieval model is constructed by selecting counter-example shots from shots without user supervision. To ensure the speed and accuracy of the QBE method, we select a small number of counter-example shots that are visually similar to given example shots but irrelevant to the query. Such shots are useful for characterizing the boundary between relevant and irrelevant shots. For our method, we first filter shots that are visually dissimilar to example shots based on SVMs on a visual feature. Then we filter shots relevant to the query based on concept detection results from pre-constructed classifiers. Shots that pass the above two tests are considered as counter-example shots. Experimental results obtained using TRECVID 2009 video data validate the effectiveness of our method.  相似文献   
39.
40.
In this paper, we propose an interactive character motion control interface that uses hands. Using their hands and fingers, the user can control a large number of degrees of freedom at the same time. We applied principal component analysis to a set of sample poses and assigned the extracted principal components to each degree of freedom of the hands (such as the hand positions and finger bending/extending angles). The user can control the blending weights of the principal components and deform the character's pose by moving their hands and bending/extending their fingers. We introduced pose and action controls, so that we can alter the standing pose and perform various actions with deformations. So that various types of actions were possible, we constructed a number of action models in advance. We introduced action model selection and action execution mechanisms. We developed methods for computing the feature vector, for applying principal component analysis, and for pose and action synthesis. In addition, we introduced a pose transition method for performing a step motion when necessary to prevent foot sliding. We present our experimental results and demonstrate the effectiveness of our interface. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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