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排序方式: 共有891条查询结果,搜索用时 15 毫秒
881.
This article proposes a new method for evaluating Product/Service System (PSS). It improves formulation of an evaluation step within an existing comprehensive method for designing PSS. The evaluation is achieved based on the importance of various customer value and each offering's contribution to the value as well as the customer's budget. Its advantage is the effective utilization of design information accumulated at the earlier part of the comprehensive method, as opposed to marketing oriented methods solely for utility measurement (e.g. conjoint analysis). Application of the entire method to a real life case at an investment machine manufacturer is presented. 相似文献
882.
883.
A series of molecularly imprinted polymer nanoparticles have been synthesized employing various template/functional monomer/crosslinking monomer ratio and characterized in detail to elucidate the correlation between the synthetic conditions used and the properties (e.g., particle size and template binding properties) of the obtained nanoparticles. In brief, the presence of propranolol (template) in the polymerization mixture turned out to be a critical factor on determination of the size as well as the binding properties of the imprinted nanoparticles. The functional monomer/crosslinking monomer ratio significantly affects the binding capability of the imprinted nanoparticles, but its influence on the size of the nanoparticles was found to be rather limited. The results obtained provide valuable clues for designing molecularly imprinted nanoparticle preparation in future studies, where fine tuning of particle size and binding properties are required to fit practical applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
884.
Seiichi Taruta Yoshitomo Iwasaki Hiromasa Nishikiori Tomohiko Yamakami Tomohiro Yamaguchi Kunio Kitajima Kiyoshi Okada 《Materials Science and Engineering: B》2012,177(7):504-509
Transparent mica glass-ceramics were prepared by heating parent glasses that had been doped with 0.5–15 mol% CeO2. During the melting and heat treatment, Ce4+ ions in the specimens were reduced to Ce3+ ions, and one or both of these ion species were then replaced with Li+ ions in the interlayers of the separated mica crystals. However, scanning transmission electron microscope (STEM) and Z-contrast imaging revealed that the mica crystals did not contain the same amount of Ce. On excitation at 254 nm, the parent glasses and glass-ceramics emitted blue light, which originated from the 5d to 4f transition of the Ce3+ ions. The emission of the glass-ceramic containing a smaller amount of Ce was attributed to the Ce3+ ions in both the glass phase and the mica crystals, whereas that of the glass-ceramics containing a larger amount of Ce was caused mainly by Ce3+ ions in the mica crystals. The dependence of the emission band of the parent glasses on the amount of Ce was a unique feature of the Ce-doped transparent mica glass-ceramics and was not observed in previous studies of Eu-doped parent glasses and mica glass-ceramics. 相似文献
885.
This paper presents a performance improvement for trajectory tracking for fast‐response and high‐precision positioning using sequential adaptive compensation for disturbances. A mathematical disturbance model formulated and parametrized by an iterative learning process can estimate the actual disturbance, and the model can be sequentially adapted using the recursive least squares method so that it shows adaptivity to disturbance variations. The proposed positioning control approach involving disturbance modeling and compensation has been verified by experiments using a linear motor‐driven table system. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(4): 52–63, 2013; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22280 相似文献
886.
Xinyue Zhu Weiming Sha Toshiki Iwasaki Weibiao Li Zhiping Wen 《International journal of remote sensing》2013,34(24):8295-8308
Using satellite imaging of the Earth at night, we quantitatively assess the rapid growth of urban areas and investigate its impact on long-term surface warming at 214 medium and large cities over eastern China. Urban growth intensity is measured using the size of the area experiencing fast night-time light increase and the distance to temperature-observation sites. Surface warming, related closely to city size, also exhibits a strong association with urban growth. A rapid increase of surface temperature is observed mainly for cities undergoing rapid urbanization (RU). Such a relation is evident over Central, South, and Northwest China, but it is weak over Northeast China, implying regional variation of temperature responses to urban growth. Satellite-derived land-surface temperature analysis suggests that cities experiencing RU are more subject to the effects of urban heat island expansion, which explains the variations of warming rate among cities within the same region. These results underscore that surface warming induced by RU might be an important component of urban climate change in eastern China. 相似文献
887.
Tomohiro Iwasaki Nami Sato Hideya Nakamura Satoru Watano 《Advanced Powder Technology》2013,24(2):482-486
A newly developed mechanochemical process for the simple aqueous phase synthesis of crystalline magnetite nanoparticles has been experimentally investigated. In this process, a suspension of ferric hydroxide precursor is milled at room temperature using a horizontal tumbling ball mill consisting of a stainless steel pot and balls. Ferric hydroxide is transformed to magnetite without the use of a reducing agent. As a model starting material for the investigation, a pH-adjusted suspension of crystalline goethite was used. As the milling time increased, goethite disappeared along with the simultaneous formation of magnetite. A single phase of magnetite was obtained after 16 h of milling. A reaction mechanism for the formation of magnetite has been proposed based on oxidation–reduction reactions, in which the corrosion of iron in the pot and balls plays an important role. Free electrons are generated by the release of ferrous ions from the stainless steel in an anodic reaction, which then reduce goethite to ferrous hydroxide in a cathodic reaction. The solid phase reaction between ferrous hydroxide and goethite produces magnetite. Not only could the mechanochemical effect induced by the collision of balls accelerate the corrosion even under alkaline conditions, it can also promote the formation and crystallization of magnetite. 相似文献
888.
W. Rother A. DewaldG. Pascovici C. FransenG. Frießner M. HacksteinG. Ilie H. Iwasaki J. JolieB. Melon P. Petkov M. PfeifferTh. Pissulla K.-O. ZellU. Jakobsson R. JulinP. Jones S. KetelhutP. Nieminen P. PeuraP. Rahkila J. UusitaloC. Scholey S. HarissopulosA. Lagoyannis T. KonstantinopoulosT. Grahn D. Balabanski 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):196-205
We report on the first experiment combining the Recoil Distance Doppler Shift technique and multistep Coulomb excitation in inverse kinematics at beam energies of 3-10 A MeV. The setup involves a standard plunger device equipped with a degrader foil instead of the normally used stopper foil. An array of particle detectors is positioned at forward angles to detect target-like recoil nuclei which are used as a trigger to discriminate against excitations in the degrader foil. The method has been successfully applied to measure lifetimes in 128Xe and is suited to be a useful tool for experiments with radioactive ion beams. 相似文献
889.
Masaya Takahashi Kenji Iwasaki Takeshi Sasaki Tomohide Kubo Ippei Mori Yasumasa Otsuka 《Applied ergonomics》2011,42(2):244-250
We investigated the association between worktime control and fatigue, sleep problems, and depressive symptoms in a sample of daytime and shift workers. A total of 3681 permanent daytime workers and 599 shift workers completed a questionnaire designed to assess the above variables. Worktime control was evaluated in terms of both “control over daily working hours” and “control over days off”. Worktime control × work schedule × gender analysis of covariance, adjusted for age and employment status, showed overall reductions in incomplete recovery, insomnia symptoms, daytime sleepiness, and depressive symptoms with increasing levels of worktime control. However, no associations between control over daily working hours and insomnia symptoms were observed in women. The reductions appeared to be more evident for control over days off. These results remained consistent after adjustments for other potential covariates. The present findings indicate that increased worktime control and enhanced control over days off in particular, may be associated with favorable health outcomes. 相似文献
890.
Masashi Miyaji Motozumi Yura Makoto Iwasaki 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(2):210-217
This paper presents the technologies for high-precision machining with high-speed and high-acceleration driving of feed-axis of double-column machining centers. In the proposed approach, linear motors whose stator has no magnet are adopted to the feed-axis to realize the high-speed and high-acceleration driving. In addition, the characteristic of generating little heat is necessary for this linear motor to keep out thermal deformations of the machine structure. In the proposed approach, the force pulsation of linear motor is reduced by arranging magnets and canceling effects of two sliders. As a result, the motor position can be controled with high accuracy. Moreover, the high-acceleration causes deflections of the machine structure such as a column. The deflections cause tracking errors at the cutting point of the tool, even if the motor position follows the position command correctly. Then, we propose to adopt the feedforward compensation based on the measured mechanical deflections. Experimental verifications using MCR-H (double-column machining center) show the significant performance improvement of the proposed method. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献