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41.
Evaluation of standing‐sitting support system with passive rotational seat mechanism in standing motion 下载免费PDF全文
Hiroyuki Sogo Tomohiro Henmi Shinichiro Shobako Kohei Ishii Suguru Eto Yuta Ogata 《Electrical Engineering in Japan》2018,205(2):16-25
Since a decrease in muscle mass of elderly people, the physical burden of them in standing‐sitting motion of a seat are increasing than young people. For this problem, several standing‐sitting support systems have been developed, and evaluations of these systems focusing on a reduction of physical load have been discussed. However, these evaluations are of support systems with an active actuators or of support systems when they use a handrail and a standing aid. Thus, an evaluation of a support system with only passive actuators has not been reported. In this paper, in standing motion with using a standing‐sitting support system with passive rotational seat mechanism which our group proposes, we objectively evaluate an effectiveness of the passive rotational seat mechanism by statistical analysis. 相似文献
42.
Catalytic dehydrogenative coupling of methane on active carbon. Effect of metal supported on active carbon 总被引:3,自引:0,他引:3
Ethane, ethene, ethyne and hydrogen are obtained in good yields via dehydrogenative coupling of methane in the presence of active carbon as a catalyst. The product yield is increased by supporting metal on active carbon. 相似文献
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44.
Seiya Abiko 《AI & Society》1999,13(1-2):164-175
The current viewpoint on technology seems to derive from the optimistic idea of the existence of pre-established harmony that any technological progress leads to people's health, and welfare. But history has shown us that this is not always the case, and that we must select the proper direction which leads to health and welfare. For that purpose, this article presents the viewpoint of technology as a kind of human care service, along with the lessons from nursing theories. Five leading nursing theories are introduced as well as their implications for technology. ‘The nursing model of technology’ is then presented. 相似文献
45.
A new MBE growth method for the fabrication of a high-quality double hetero-epitaxial Si/γ-Al2O3/Si structure was recently developed. In the present work, characteristics of NMOSFETs fabricated on the Si/γ-Al2O3/Si structure were investigated, and compared with those on a Si/MgAl2O4/Si structure. A γ-Al2O3 layer was created from a MgAl2O4 layer by reaction with Si beams as follows: MgAl2O4 + Si → γ-Al2O3 + SiO ↑ + Mg ↑. The MBE growth of Si on the effectively restructured γ-Al2O3 layer was then performed at a substrate temperature of 700° C, 150° C lower than for the MBE growth of Si on a MgAl2O4/Si substrate. The electron field effect mobility and leakage current between source and drain for the NMOSFETs fabricated
on Si/γ-Al2O3/Si structures were 660 cm2/V · s and 2.8 pA/μm respectively, and exhibited a higher level of performance than those on a Si/MgAl2O4/Si structure. In the Si/MgAl2O4/Si, SIMS measurements confirmed that autodoped Al and Mg atoms near the interface between the Si epi-layer and MgAl2O4/Si substrate diffused anomalously and accumulated at the surface during device fabrication processes. These autodoped Al
and Mg atoms acted as ionized impurities during test operation. Suppression of autodoping from insulator layers during the
MBE growth of Si was thus deemed essential to the improvement of NMOSFET characteristics. In the Si/γ-Al2O3/Si structure, autodoped atoms were scarcely detectable. It was therefore concluded that the Si/γ-Al2O3/Si structure under study was very promising for SOI device applications. 相似文献
46.
47.
Zhanpeng Lu Tetsuo Shoji Yoichi Takeda Yuzuru Ito Akira Kai Seiya Yamazaki 《Corrosion Science》2008,50(2):561-575
The stress corrosion cracking (SCC) growth kinetics for a cold worked 316L stainless steel was continuously monitored in high purity water at different temperatures and dissolved oxygen (DO) levels under a K (or Kmax) of 30 MPa m0.5. The total SCC test time was more than 8000 h to make sure the steady state crack growth rate under each test condition could be reached. Crack growth rate (CGR) increases with increasing temperature in the range 110-288 °C. A typical intergranular-cracking mode is identified. Depending on the previous test condition, especially the temperature, three kinds of crack growth kinetics, i.e., increasing with testing time then becoming steady, being constant during the whole period, or decreasing with test time then becoming steady, are identified and discussed. Time-dependent and testing history-dependent crack growth modes were confirmed in two series of tests in 2 ppm DO and 7.5 ppm DO pure water. The apparent activation energies are calculated and compared with other data in different environments under different applied loading levels for understanding the cracking mechanism. 相似文献
48.
To estimate the response to hormone replacement therapy (HRT) by bone metabolic markers, 36 patients with postmenopausal osteoporosis or osteopenia were studied to assess the correlation between percent baseline changes in lumbar bone mineral density (BMD) after 12 months and those in various bone metabolic markers after 3, 6, and 12 months of HRT. All the patients were treated with 0.625 mg of conjugated estrogen and 2.5 mg of medroxyprogesterone per day and continued for 12 months. BMD was significantly increased up to 4.19 +/- 0.87% after 6 months and 4.93 +/- 1.27% after 12 months of HRT (p = 0.0001 by analysis of variance). In accordance with this, changes in the levels of osteocalcin (p = 0.041), alkaline phosphatase (p = 0.0001), N-terminal osteocalcin (p = 0.0001), urinary excretion of pyridinoline/Cr (p = 0.0001), and deoxypyridinoline/Cr (p = 0.0001) were significantly decreased, respectively. Among these bone metabolic markers, only the change in the serum N-terminal osteocalcin at 3 months (r = 0.557, p = 0.0022), at 6 months (r = 0.470, p = 0.0184), and at 12 months (r = 0.545, p = 0.0061) significantly correlated with the change in BMD 12 months after HRT. The elution profiles of immunoreactive osteocalcin-related molecules in serum fractionated by reverse-phase high performance liquid chromatography revealed that the N-terminal fragment as well as the intact osteocalcin molecule decreased after 3 months of HRT. These results demonstrate that N-terminal osteocalcin is a suitable predictor for estimating good responders to HRT in postmenopausal women. 相似文献
49.
Seiya Suzuki Takuya Iwasaki K. Kanishka H. De Silva Shigeru Suehara Kenji Watanabe Takashi Taniguchi Satoshi Moriyama Masamichi Yoshimura Takashi Aizawa Tomonobu Nakayama 《Advanced functional materials》2021,31(5):2007038
Germanene, a 2D honeycomb germanium crystal, is grown at graphene/Ag(111) and hexagonal boron nitride (h-BN)/Ag(111) interfaces by segregating germanium atoms. A simple annealing process in N2 or H2/Ar at ambient pressure leads to the formation of germanene, indicating that an ultrahigh-vacuum condition is not necessary. The grown germanene is stable in air and uniform over the entire area covered with a van der Waals (vdW) material. As an important finding, it is necessary to use a vdW material as a cap layer for the present germanene growth method since the use of an Al2O3 cap layer results in no germanene formation. The present study also proves that Raman spectroscopy in air is a powerful tool for characterizing germanene at the interfaces, which is concluded by multiple analyses including first-principles density functional theory calculations. The direct growth of h-BN-capped germanene on Ag(111), which is demonstrated in the present study, is considered to be a promising technique for the fabrication of future germanene-based electronic devices. 相似文献
50.
Y. Ogata S. Uchiyama M. Hayashi M. Yasuda F. Hine 《Journal of Applied Electrochemistry》1990,20(4):555-558
The pH on the surface of an ion-exchange membrane was measured with a microprobe in a laboratory scale chlor-alkali cell to study the leakage of OH– through the membrane. The solution pH in the vicinity of the membrane facing the anode was found to be considerably higher than that in the bulk solution because of penetration and leakage of OH–. The pH varied with the membrane type. This explains why the carboxylate membrane is not protonated and can be used as a separator in chlor-alkali cells.Deceased. 相似文献