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81.
82.
Masafumi Yamamoto Makoto Iwasaki Kazuaki Ito Nobuyuki Matsui 《Electrical Engineering in Japan》2010,171(2):31-39
This paper presents a modeling methodology for unknown disturbances in mechatronics systems, based on disturbance estimation using an iterative learning process. In disturbance modeling, nonlinear frictions are specially handled as disturbances in the mechanisms, which mainly degrade trajectory control performance. Friction can be mathematically modeled by using learned estimation data as a function of the displacement, velocity. acceleration, and jerk of the actuator. This model has the distinctive feature that friction compensation can be achieved with a generalization capability for different conditions. The proposed positioning control approach with disturbance modeling and compensation has been verified by experiments using a table drive system on a machine stand. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(2): 31–39, 2010; Published online in Wiley InterScience ( www. interscience.wiley.com ). DOI 10.1002/eej.20928 相似文献
83.
In this study we revisit Weiser’s (1991) [5] vision of seamlessly integrated computing. We focus on nomadic workers who rely extensively on mobile technologies to conduct work. Using Star and Ruhleder’s (1996) [10] properties of infrastructure, we discuss how nonroutine users of infrastructure face particular challenges. We conducted an ethnographic investigation of nomadic workers in a large distributed organization. We examined strategies that they use to assemble their mobile office, to seek resources, and to synchronize with others across time zones. We discuss how their strategies are challenged by their lack of local knowledge of infrastructure. Our results suggest that until the field of pervasive computing can attain Weiser’s vision, the very users of ubiquitous computing need infrastructure to be visible. We discuss the implications for a design to support nomadic work. 相似文献
84.
Walber Arantes da Silva Juliana Aparecida Aricetti Alice Eiko Murakami Jesuí Vergílio Visentainer Makoto Matsushita 《LWT》2009,42(2):660-73
This experiment was carried out with 58-week old laying quails (Coturnix coturnix japonica) assigned to four treatment groups with eight quails per replication in six repetitions in a completely randomized design. The treatments consisted of diets with different levels of flaxseed (0, 1.5, 3.0, and 5.0%). The amounts of cholesterol and total lipids and the fatty acid composition of quail egg yolk were determined in four 21-day cycles. No difference was found in cholesterol levels between the four treatments and the four cycles. The increased ingestion of linolenic acid (LNA) in diet reduced the formation of arachidonic acid (AA) significantly. The 3.0 and 5.0% treatment groups presented a reduction in total saturated fatty acids (TSFA) with the increase in percent flaxseed in feed comparatively to the control value. The n-3 fatty acid level was high in all treatments when compared to that of the control group. The n-6/n-3 ratio decreased from 21.30 (control) to 4.52 (5.0%), which is a better value from the nutritional viewpoint. 相似文献
85.
Takahiro Funami Sakie Noda Makoto Nakauma Sayaka Ishihara Rheo Takahashi Saphwan Al-Assaf Shinya Ikeda Katsuyoshi Nishinari Glyn O. Phillips 《Food Hydrocolloids》2009,23(2):548-554
Aqueous solutions of gellan gum with comparable molecular mass but with different acyl contents were investigated by atomic force microscopy and rheological measurements in the presence of sodium chloride (NaCl). Results obtained were discussed in relation to our previous report using potassium chloride (KCl) as an added salt. For a low-acyl sample, continuous fibrous network structures were identified microscopically as in the case of KCl. The network structures were more heterogeneous than those formed with KCl in terms of the height distribution of molecular assemblies. Rheological thermal hysteresis between sol–gel transitions was detected as in the case of KCl. The storage modulus (G′) of the gelled system was ca. 15% of the corresponding data with KCl at 20 °C. For a high-acyl sample, no continuous network structures were identified but branches with observable ends were identified as in the case of KCl. The hysteresis was less evident than the corresponding data with KCl and for the low-acyl sample with NaCl. Also, G′ values at 20 °C were ca. 30% and 20% of the corresponding data with KCl and for the low-acyl sample with NaCl, respectively. Continuousness and homogeneity of network structures related to the hysteresis and elasticity of the system, respectively. 相似文献
86.
Matsui T Matsumura K Hagisawa K Ishihara M Ishizuka T Suzuki M Kurita A Kikuchi M 《IEEE transactions on bio-medical engineering》2002,49(6):621-623
The purpose of this study is to investigate the vascular wall with a thermally self-regulating, cylindrical stent made of a low Curie temperature ferromagnetic alloy. Physiologic saline was circulated in the silicone model vessel implanted with the stent. The stent-temperature remained nearly constant for variable saline flows, saline temperatures, and magnetic flux densities. Stent implants of this type in human blood vessels could potentially enable thermotherapy and temperature determination without catheterization. 相似文献
87.
We applied a Mo/B4C multilayer coating to a laminar holographic grating with 2400 grooves/mm and a 1-m radius of curvature. By use of synchrotron soft x rays the multilayer-coated grating was evaluated to have diffraction efficiencies of 3.1% and 0.017% for s- and p-polarized radiation, respectively, at a 6.7-nm wavelength at a 45.35 degrees grazing angle of incidence in the +1 (inside) grating order. Thus the polarizance was estimated to be 98.9% at least. The zero-order peak was suppressed by the destructive interference caused by the groove profile. 相似文献
88.
Tanaka M Yoshimura M Suto M Yokota A Asano K Sukara E Tomita F 《Journal of Bioscience and Bioengineering》2002,93(6):531-536
A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region. 相似文献
89.
Kim YJ Yoshizawa M Takenaka S Murakami S Aoki K 《Journal of Bioscience and Bioengineering》2002,93(6):584-588
The two ammonia-assimilating enzymes glutamate dehydrogenase (GDH; EC 1.4.1.4) and glutamine synthetase (GS; EC 6.3.1.2) were synthesized steadily during the cell growth of Klebsiella pneumoniae F-5-2 that can utilize NH4+ and NO3- simultaneously under aerobic conditions. The enzymes were purified to homogeneity from cell extracts and characterized. The molecular mass of the purified GDH was 300 kDa with six identical 52-kDa subunits. GDH showed its maximal activity (aminating) at pH 8.0 and was stable between pHs 5.5 and 11.5. The enzyme was NADP-specific and strongly inhibited by Ag+. It catalyzed the amination of 2-ketovalerate, 2-ketoadipate, and 2-ketobutyrate, in addition to 2-ketoglutarate. The purified GS has a molecular mass of 470 kDa with eight identical 60-kDa subunits. GS showed its maximal activity at pH 8.0 and was stable between pHs 6.0 and 7.0. The enzyme was strongly inhibited by Fe3+, Hg2+, and Cu2+. 相似文献
90.
Makoto Ishii Kenji Saito Tomokazu Shiga Kiyoshi Igarashi Shigeo Mikoshiba Jooyul Lee Kyoung Ho Kang Heehwan Kim Changbae Park 《Journal of the Society for Information Display》2002,10(1):5-10
A hybrid AWD/AND drive technique has been developed in which an Address‐While‐Display (AWD) scheme is combined with an AND logic characteristic that gas discharges demonstrate. The AWD technique enables AC‐PDPs to be driven at high luminance, while the AND logic reduces the number of scan drivers by an order of magnitude. A detailed analysis of the addressing operation has been made. The hybrid drive utilizes the AND logic in two ways: (1) a combination of two voltage pulses and (2) a combination of a voltage pulse and discharge‐priming particles. It was found that the addressing operation requires the establishment of a discharge between the scan and data electrodes, and also between the scan and display electrodes. 相似文献