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21.
Reactive blending of polyamide 6 (PA) with polyethylene (PE) having reactive sites, maleic anhydride (MAH content=0.1 wt%),and glycidyl methacrylate (GMA content=3-12 wt%), was carried out at 70/30 and 65/35 (PA/PE) blend ratios. Blend morphology evolved by reactive blending was analyzed by light scattering and transmission electron microscopy. The blends were then irradiated by electron beam. The degree of crosslinking was estimated by measuring the dynamic storage modulus at a temperature above melting point of PA. It was found that surface-to-surface interparticle distance τ was significantly reduced by the micelle formation via pull-out of in situ-formed graft copolymers. The blend with shorter τ was crosslinked by electron-beam irradiation at the lower dose level. A blend having the minimum τ (∼0.2 μm) was nicely crosslinked at a low dose level same as for PE, and even for the PA matrix system.  相似文献   
22.
Pervaporation (PV) is a membrane technology that holds great promise for industrial applications. To better understand the PV mechanism, PV dehydrations of various types of organic solvents (methanol, ethanol, iso-propanol, tert-butanol, and acetone) were performed on five types of organosilica and two types of silicon carbide-based membranes, all with different pore sizes. Water permeance was dependent on the types of organic aqueous solutions, which suggested that organic solvents penetrated the pores and hindered the permeation of water. In addition, water permeance of various types of membranes in PV was well correlated with hydrogen permeance in single-gas permeation. Furthermore, a clear correlation was obtained between the permeance ratio in PV and that in single-gas permeation, which was confirmed via the modified-gas translation model. These correlations make it possible to use single-gas permeation properties to predict PV performance.  相似文献   
23.
In proton-conducting oxides, analyses for their electronic structure contribute to the understanding of interactions between defects in them. In this study, electronic band alignment of (1−x)BaZr0.8Y0.2O3−δ(BZY)–xSrZr0.95Y0.05O3−δ(SZY) proton-conducting solid-solution system (BSZY) which has high defect concentration and the deep valence band is experimentally investigated. By using thin-film specimens for optical absorption measurements, absorption edges derived from electron transition from the valence band to the conduction band which was insensitive to the proton incorporation were clearly observed in spite of the high defect concentration. The obtained optical band gap energy increased from 5.61 to 5.89 eV with increasing x, which was consistent with a composition dependence of Zr(Y)O6 octahedral tilting. Ultraviolet photon-yield spectroscopy (UV-PYS) measurements under vacuum condition revealed that BZY and SZY had ionization energy of 6.98 and 7.31 eV, respectively, and thus the absolute energy levels of the valence band maximum and the conduction band minimum of BSZY were experimentally clarified. We propose that the combination of the optical absorption measurements using thin-film specimens and the UV-PYS measurements under vacuum condition is effective in evaluating fundamental electronic structures of proton-conducting oxides.  相似文献   
24.
This paper describes the development of auto‐stereoscopic three‐dimensional (3D) display with an eye‐tracking system for not only the X‐axis (right–left) and Y‐axis (up–down) plane directions but also the Z‐axis (forward–backward) direction. In the past, the eye‐tracking 3D system for the XY‐axes plane directions that we had developed had a narrow 3D viewing space in the Z‐axis direction because of occurrence of 3D crosstalk variation on screen. The 3D crosstalk variation on screen was occurred when the viewer's eye position moved back and forth along the Z‐axis direction. The reason was that the liquid crystal (LC) barrier pitch was fixed and the LC barrier was able to control the only barrier aperture position. To solve this problem, we developed the LC barrier that is able to control the barrier pitch as well as the barrier aperture position in real time, corresponding to the viewer's eye position. As a result, the 3D viewing space has achieved to expand up to 320–1016 mm from the display surface in the Z‐axis direction and within a range of ±267 mm in the X‐axis direction. In terms of the Y‐axis direction, the viewing space is not necessary to be considered, because of a stripe‐shaped parallax barrier.  相似文献   
25.
We attempted to predict activity/dominance for soccer games, where activity is defined as the degree of activity of the game as perceived by the viewer, whereas dominance is the degree at which the viewer perceives a particular team to dominate over the other team. Such activity/dominance information would help a layman viewer understand the game. It would also enable construction of an automatic digest creation system that extracts scenes having high activity/dominance. There are two facets of this study: 1. The main part of the underlying prediction model consists of a Stick-Breaking Hidden Markov Model, where the data automatically estimates the number of states of the Markov process behind the data. 2. The data used in this paper is vector time-series data consisting of player, referee, and ball positions, together with team information, acquired by a set of fixed cameras. The problem was approached with a Bayesian framework where learning and prediction were implemented by three different methods: Markov Chain Monte Carlo, Expectation Maximization, and Variational Bayes. The proposed method was tested using a dataset consisting of 10 professional soccer games and was compared against standard regression methods.  相似文献   
26.
People routinely carry mobile devices in their daily lives and obtain a variety of information from the Internet in many different situations. In searching for information (content) with a mobile device, a user’s activity (e.g., moving or stationary) and context (e.g., commuting in the morning or going downtown in the evening) often change, and such changes can affect the user’s degree of concentration on his or her mobile device’s display and information needs. Therefore, a search system should provide the user with an amount of information suitable for the current activity and a type of information suitable for the current context. In this study, we present the design and implementation of a content search system that considers a mobile user’s activity and context, with the goal of reducing the user’s operation load for content search. The proposed system switches between two kinds of content search systems according to the user’s activity: the location-based content search system is activated when the user is stationary (e.g., standing and sitting), while a menu-based content search system is activated when the user is moving (e.g., walking). Both systems present information according to user context. The location-based system presents detailed information via menus and a map according to location-based categories. The menu-based system presents only a few options to enable users to get content easily. Through user experiments, we confirmed that participants could get desired information more easily with this system than with a commercial search system.  相似文献   
27.
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed.  相似文献   
28.
Experimental methods and preliminary results of high-precision measurements of the 3 He melting curve in high magnetic fields have been described. The purpose of this work is twofold. One is to establish a reliable millikelvin temperature scale in high fields (T 10 mK, B 15 T), The other is to investigate a high field region of the magnetic phase diagram of solid 3 He by measuring the melting pressure down to temperatures below 1 mK. Besides the two superfluid transitions, the phase transition temperatures between the spin ordered solid and the paramagnetic solid, T HFP , were determined at B = 12 and 10 T with good accuracy, which is an extension of previous measurements up to 8 T. The present T HFP (B) line can not be scaled to that at a higher density with a single Grüneisen parameter, indicating a variation of density dependencies of the multiple-spin exchange interactions.  相似文献   
29.
The tangential momentum accommodation coefficient (TMAC) was investigated experimentally from the mass flow rate through a single microtube under the slip flow and the early part of the transition regime. The measurements were carried out by the constant-volume method under the mean Knudsen number smaller than 0.3, which is based on the mean pressure of the inlet and the outlet of the microtube, to apply the second-order slip boundary condition. To measure TMACs on various materials, quite large microtube was employed, which require the reduction in leakage. TMAC was obtained from the slip coefficient determined by the relation of the mass flow rate to the mean Knudsen number. The obtained mass flow rate was well explained by the theoretical equation. TMACs of deactivated-fused silica with argon, nitrogen, and oxygen were measured, showing the tangential momentum was not accommodated completely to the surface, and the values showed good agreement with previous studies. From the comparison between microtubes with different inner diameter, it is showed that TMAC is determined mainly by gas species and surface material.  相似文献   
30.
Temperature dependence of water vapor sorption and electro-active polymer actuating behavior of free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) was investigated by means of sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, having a specific surface area of 0.13 m2 g?1, sorbed water vapor of 1080 cm3(STP) g?1, corresponding to 87 wt%, at relative water vapor pressure of 0.95. A temperature rise from 25 °C to 40 °C lowered sorption degree, indicative of an exothermic process, where isosteric heat of sorption decreased with increasing water vapor sorption and the value reached 43.9 kJ mol?1, being consistent with the heat of water condensation (44 kJ mol?1). Upon application of 10 V, the film underwent contraction of 2.46% at 5 °C caused by desorption of water vapor due to Joule heating, which slightly decreased to 2.10% at 45 °C. The speed of contraction was one order of magnitude faster than that of expansion and less dependent on the temperature since water vapor sorbed in the film were forced to desorb by Joule heating. In contrast, the higher the temperature the faster the film expansion because diffusion coefficient increased as the temperature became higher.  相似文献   
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