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21.
Yoshiyuki Abe Kazuyuki Kakegawa Yoshinori Sasaki 《Journal of the American Ceramic Society》1992,75(1):234-236
A complex perovskite of Sr(Cu x Zn1- x )1/2 W1/2 O3 (SCZW) is synthesized by a new combination of wet and dry processess. Mixed oxides containing Cu2+ and Zn2+ (CZ) are prepared by the wet process (coprecipitate method). SCZW is obtained by the dry process (mixed-oxide method) from a mixture of CZ, SrCO3 , and WO3 . SCZW has practically no compositional, unlike solid solutions prepared by the conventional dry method. The wet–dry process method is useful because the wet process is applied to only B-site cations having the same valence. 相似文献
22.
Molecular species of 1-O-alk-1′-enyl-2-acyl-, 1-O-alkyl-2-acyl-, and 1,2-diacyl-sn-glycero-3-phosphoethanolamine (EPL) andsn-glycero-3-phosphocholine (CPL) of Japanese oysterCrassostrea gigas were analyzed by selectedion monitoring gas chromatography/mass spectrometry using electron impact ionization. The characteristic
fragment ions, [RCH=CH+56]+ due to the alkenyl residue in thesn-1 position and [RCO+74]+ due to the acyl residue in thesn-2 position of alkenylacylglycerols, [R+130]+ due to the alkyl residue in thesn-1 position and [RCO+74]+ due to the acyl residue in thesn-2 position of alkylacylglycerols, [RCO+74]+ due to the acyl residues in thesn-1 and/orsn-2 positions of diacylglycerols, and [M−57]+ being indicative of the corresponding molecular weight, were used for structural assignments.
For alkenylacyl EPL and CPL, 19 and 16 molecular species were determined, respectively. Two molecular species, 18∶0alkenyl-22∶6n−3
and 18∶0-alkenyl-22∶2-non-methylene interrupted diene (NMID), amounted to 53.2% and 47.9%, respectively. The alkylacyl EPL
and CPL consisted of 16 and 20 molecular species, respectively, and the prominent components were 18∶0alkyl-22∶2NMID, 20∶1alkyl-20∶1n−11
(27.4%) and 20∶1alkyl-20∶2NMID (16.3%) in the former, and 16∶0alkyl-20∶5n−3 (23.0%) and 16∶0alkyl-22∶6n−3 (21.6%) in the latter.
For the diacyl EPL and CPL, 14 and 51 molecular species were determined, respectively. The major molecular species were 18∶0–20∶5n−3
(37.4%), 16∶0–20∶5n−3 (14.2%) and 18∶1n−7–22∶2NMID (13.2%) in the former, and 16∶0–20∶5n−3 (33.4%) and 16∶0–22∶6n−3 (22.3%)
in the latter. It was found that there were significant differences in the molecular species between the alkylacyl and diacyl
EPL and the alkylacyl and diacyl CPL; the number of molecular species was larger in CPL than in EPL, while the number of total
carbons and double bonds of the major molecular species were larger in the EPL than in the CPL. Alkenylacyl EPL were similar
to alkenylacyl CPL in molecular species composition. 相似文献
23.
Shinsuke Nagamine Yosuke Mizuno Yuta Hikima Kiyomi Okada Long Wang Masahiro Ohshima 《应用聚合物科学杂志》2021,138(7):49851
Cellulose microfibers (CMFs) having surfaces modified with polydopamine (PDPA) and octadecylamine (ODA) were prepared, and their reinforcing abilities for polypropylene (PP) were investigated. The PDPA coating was made via self-polymerization of dopamine (P-CMF), and subsequent alkylation was conducted by the reaction with ODA (OP-CMF). The modified CMFs exhibited improved dispersibility in the PP matrix due to the reduced hydrophilicity. The OP-CMF/PP composite prepared by batch mixing had a higher tensile modulus compared to that for the pure PP and composites with unmodified CMFs. However, excess alkylation lowered the tensile modulus, and the presence of an optimal degree of alkylation was demonstrated. The CMF/PP-IM composites fabricated by injection molding exhibited improved tensile properties compared to those prepared by batch mixing. Both the tensile modulus and yield stress were increased by increasing the CMF content and improved by the surface modification of the CMFs. 相似文献
24.
Tomohiro Hashiguchi Yutaka Takita Kazuyuki Tajima Toru Katagiri 《Journal of Network and Systems Management》2016,24(3):557-577
Shared protection/restoration is a promising solution for reducing protection resources and is supported at each layer of the current multi-layer networks. Software-defined networking is expected to reduce equipment cost as well as operational cost by orchestrating these shared protection functionalities. However, although protection resource sharing improves link utilization, it sometimes increases the required equipment. Meanwhile, traffic re-aggregation at each layer is an important technique for low volume traffic to utilize the underlying link capacity more efficiently, but re-aggregation also makes it difficult to share protection resources with traffic at lower layers. In this paper, we present multi-layer network design strategy and method that reduce equipment cost by means of both traffic re-aggregation at each layer and protection resource sharing among multiple service traffic at different layers. The strategy first prioritizes traffic re-aggregation at each layer, and then maximally delegates shared protection to lower layers as long as it does not increase the required capacity at the lower layer. Evaluation results from the example three-layer networks confirm that the proposed method can effectively reduce equipment cost compared to the conventional design method. Cost reduction is achieved by leveraging shared protection functions at multiple layers. 相似文献
25.
Recently, various robots with many degrees of freedom, such as rescue robots and domestic robots, have been developed and
used in practical applications. It is difficult to control such robots autonomously in real environments, because in order
to control the many degrees of freedom, we have to observe many states, calculate huge amounts of information, and operate
many actuators. In this study, we consider a flexible robot without sensors or controllers that can determine the inclination
of a slope and climb up the slope. In order to demonstrate the effectiveness of the proposed framework, we have developed
a prototype robot and conducted experiments. The result indicates that the robot could determine the inclination and climb
up a gentle slope autonomously. Thus, we have realized an autonomous robot that has no explicit sensors or controllers. 相似文献
26.
Adaptation is a fundamental property of human perception. Recently, it was found that there are two opposite types of adaptation to repetitive stimuli with a temporal difference. In this article, we construct an integrative model of adaptation. We model the perception as a Bayesian inference, and represent the two types of adaptation as changes in the likelihood function and the prior distribution in the Bayesian inference. We examine our model analytically and show how the types of adaptation depend on model parameters. 相似文献
27.
An interference method utilizing conic-wave-front light for the fabrication of a concentric-circular and chirped grating is proposed. The design method and fabrication of an interference lens that generates conic-wave-front light are also shown. A focusing element is constructed from a concentric-circular grating coupler with a 0.4-mm diameter and a concentric-circular focusing grating coupler with an annular aperture of 2-mm focal length and 2.0-4.0-mm diameter. Light-convergence experiments using the focusing element were able to obtain a focusing spot of 0.5 μm × 0.7 μm at half-intensity widths for a wavelength of 820 nm in combination with liquid-crystal polarization elements. 相似文献
28.
29.
Tatsuhiko Matsumoto Satoru Kubota Yuta Kubota Kenta Imabayashi Kazuyuki Kishimoto Seiichi Goshi Shigeki Imai Youichi Igarashi Shuichi Haga Takehiro Nakatsue 《Journal of the Society for Information Display》2011,19(11):813-820
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
30.
Greedy versus social: resource-competing oscillator network as a model of amoeba-based neurocomputer
A single-celled amoeboid organism, the true slime mold Physarum polycephalum, exhibits rich spatiotemporal oscillatory behavior and sophisticated computational capabilities. The authors previously created
a biocomputer that incorporates the organism as a computing substrate to search for solutions to combinatorial optimization
problems. With the assistance of optical feedback to implement a recurrent neural network model, the organism changes its
shape by alternately growing and withdrawing its photosensitive branches so that its body area can be maximized and the risk
of being illuminated can be minimized. In this way, the organism succeeded in finding the optimal solution to the four-city
traveling salesman problem with a high probability. However, it remains unclear how the organism collects, stores, and compares
information on light stimuli using the oscillatory dynamics. To study these points, we formulate an ordinary differential
equation model of the amoeba-based neurocomputer, considering the organism as a network of oscillators that compete for a
fixed amount of intracellular resource. The model, called the “Resource-Competing Oscillator Network (RCON) model,” reproduces
well the organism’s experimentally observed behavior, as it generates a number of spatiotemporal oscillation modes by keeping
the total sum of the resource constant. Designing the feedback rule properly, the RCON model comes to face a problem of optimizing
the allocation of the resource to its nodes. In the problem-solving process, “greedy” nodes having the highest competitiveness
are supposed to take more resource out of other nodes. However, the resource allocation pattern attained by the greedy nodes
cannot always achieve a “socially optimal” state in terms of the public cost. We prepare four test problems including a tricky
one in which the greedy pattern becomes “socially unfavorable” and investigate how the RCON model copes with these problems.
Comparing problem-solving performances of the oscillation modes, we show that there exist some modes often attain socially
favorable patterns without being trapped in the greedy one. 相似文献