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21.
For decades, numerous artificial muscles have been proposed in order to implement beneficial features of biological muscles into robotics. Unfortunately, traditional artificial muscles experienced difficulties in imitating properties of the biological muscles due to mechanical and control issues. Recently, twisted and coiled polymer actuators (TCP) have been shown to produce large mechanical power via thermal stimulations and strong linearity. In this paper, a high-performance TCP thermally cycled by electrical heating and forced convective liquid cooling is designed and associated control algorithms are presented. We elaborate the model of the TCP that is simple, yet provides insight into how the electrical heating and the forced convective liquid cooling contribute to the TCP actuation. The proposed model is verified by experimental studies. Based on the proposed model, we design a feedforward–feedback controller and switching laws, which actively control the TCP in both the heating and cooling cycles. Furthermore, we extend our control methodology to agonist–antagonist TCPs. From the experimental studies, the proposed method is shown to be effective in both single TCP and antagonistic TCPs. 相似文献
22.
Hori H. Kitayama Y. Kitano M. Yabuzaki T. Ogawa T. 《Quantum Electronics, IEEE Journal of》1983,19(2):169-175
Experimental results are shown on the frequency stabilization of a GaAlAs laser using a Doppler-free spectrum in the saturated absorption of the Cs-D2 line at 852.1 nm. The frequency stability (Allan variance) between3.0 times 10^{-12} and1.0 times 10^{11} was obtained at the averaging time between 0.1 and 1000 s. 相似文献
23.
Y Naito K Ohori M Tanaka T Kamo S Baba T Hori K Hashizume H Sugimura 《Canadian Metallurgical Quarterly》1998,48(8):603-610
In order to characterize human desmoid tumors in vitro, the production of collagen and elastin and the expression of collagen types alpha1(I), alpha1(III) and transforming growth factor (TGF)-beta1 mRNA were investigated in six desmoid tumors; five derived from familial adenomatous polyposis patients and one from a sporadic case. The proportion of collagen production to total protein production was determined by 3H-imino acid incorporation, an indicator of collagen synthesis, using high-performance liquid chromatography (HPLC). The proportion of collagen production to total protein production was much higher in all six desmoid tumors compared with human skin fibroblasts (HSF). Quantitatively, the rate of elastin synthesis in desmoid tumor cells monitored by valine-proline peptide was also significantly higher than in HSF. Pro-alpha1(I) collagen mRNA was highly expressed in both desmoid tumors and HSF at approximately the same level, whereas pro-alpha1(III) collagen mRNA was more abundant in some of the desmoid tumors than the normal skin fibroblastic cell lines. Tumor growth factor-beta1 mRNA, which is believed to stimulate collagen synthesis, was expressed in both desmoid tumors and HSF to the same extent. These results demonstrate the increased formation of collagen and elastin in desmoid tumors in vitro and suggest that the increased synthesis of elastin rather than of collagen and TGF-beta1 may be involved in increased fibrogenesis by desmoid tumors. 相似文献
24.
A case of small epithelioid hemangioendothelioma encapsulated by an egg-shaped bony shell composed of newly formed mature lamellar bone is presented. A nodule measuring 10 x 5 x 5 mm was excised from inside of the right cheek muscle of a 46-year-old man. Histopathologically, the nodule consisted mainly of round-to-short spindled epithelioid cells with round nuclei and occasional cytoplasmic vacuoles associated with some foci of osseous metaplasia. Characteristically, egg shell-like lamellar bone enclosed this lesion showing well-circumscribed appearance. The main component cells were immunohistochemically stained positive for factor VIII-related antigen, CD 34, UEA-1, and vimentin, and proved to be vascular endothelial cells. The term ossifying epithelioid hemangioendothelioma is proposed for this unique lesion. This type of epithelioid hemangioendothelioma has not been previously reported to our knowledge, and differentiation from ossifying fibromyxoid tumor of soft parts is considered to be important. 相似文献
25.
H Nagasaka M Taguchi Y Mizumoto K Hori K Hayashi M Sugai Y Murakami K Oohara I Matsumoto T Hori 《Canadian Metallurgical Quarterly》1996,45(6):750-755
The influence of timing of administration of preoperative pentazocine on pain and analgesic requirements after surgery was studied in 46 patients undergoing total abdominal hysterectomy. Twenty-three patients received thiamylal 5 mg.kg-1 on induction of anesthesia, followed by pentazocine 30 mg or 60 mg before surgical incision (group A). Twenty-three control patients received pentazocine 30 mg or 60 mg, 5 min after abdominal incision (group B). The visual analogue scales for pain 24 h after operation were 6.0 cm at 30 mg dose in group A or 5.3 cm at 60 mg dose in group A and 5.7 cm at 30 mg dose in group B or 4.7 cm at 60 mg dose in group B. There were no differences in the visual analogues scales. Pentazocine consumption in the first 24 h after surgery was 67.5 mg at 30 mg dose in group A or 52.5 mg at 60 mg dose in group A and 70.9 mg at 30 mg dose in group B or 51.8 mg at 60 mg dose in group B. We conclude that postoperative pentazocine consumption and pain scores are no different when pentazocine is given before or after skin incision for abdominal hysterectomy and that there is no clinically useful pre-emptive analgesic effect with these doses of pentazocine. 相似文献
26.
The shifts in membrane potential, caused by the injection of glucose into a permeation cell, were measured using immobilized (entrapped) glucose oxidase membranes. No, pH change in the permeation cell was observed upon injection of glucose, but the shift in membrane potential was definitely detected. The shift in membrane potential was observed under nitrogen bubbling (in the absence of oxygen) using initially used enzyme membranes. It was, therefore, suggested that the shifts in membrane potential were not caused by an enzyme-substrate reaction, but by binding of the substrate to the enzyme, which indues a conformational change in the enzyme and leads to a change in charge density in the enzyme membrane. This mechanism is also supported by the fact that the shifts in membrane potential were observed upon injection of not only D-glucose but also L-glucose as reported in our previous study [J. Chem. Soc. Faraday Trans., 87 , 695 (1991)]. © 1994 John Wiley & Sons, Inc. 相似文献
27.
28.
Nora MartinezKenji Hisada Isao TabataKazumasa Hirogaki Susumu YonezawaTeruo Hori 《The Journal of Supercritical Fluids》2011,56(3):322-329
The effect of thermal treatment to improve the metal adhesion into poly-(p-phenylene terephthalamide) (PPTA), e.g. aramid fiber, has been investigated. After palladium(II)-hexafluoroacetylacetonate metal complex, Pd(hfac)2, seeding into the fiber using supercritical fluid carbon dioxide, scCO2, a post-thermal treatment was conducted. As a result, after carrying out electroless copper plating, the adhesive strength between polymer substrate and copper layer greatly increased. Also, in order to have a better comprehension on decomposition reactions of Pd(hfac)2 under supercritical conditions, remains of metal complex were analyzed using electron ionization mass spectrometry technique (EI-MS). EI-MS mass spectra derived from Pd(hfac)2 gave us useful information about its dissociation reactions and reaction temperature under supercritical conditions. Additionally, to verify the Pd particles seeding in the fiber surface, X-ray photoelectron spectrometry (XPS) analyses were performed. The results confirmed that post-thermal treatment induced Pd particles diffusion and deeper penetration of Pd complex and its fragments into the fiber. 相似文献
29.
Although the production of electro‐conductive aramid fibers is efficient, the method needs to be modified before it can be applied to aramid films. Whereas impregnation of an aramid film with a metal complex using supercritical CO2 is achievable, the relatively low adhesion strength of the metal layer applied using electroless copper plating is problematic. To solve this problem, thermal treatment was conducted before, after, or both before and after electroless plating. The rationale for using thermal treatment to improve the adhesiveness of the plated layer was based on the findings that (1) an aramid film contains a significant amount of water (about 3.5 % w.o.f.), which might have a negative impact on adhesion; and (2) because an impregnated metal complex liberates metal catalyst by thermal decomposition during impregnation, a supplementary thermal action might liberate more catalyst and thereby improve adhesion. We found that thermal treatment improved adhesion of the metal layer to the aramid film. Moreover, we discovered that with respect to electroless copper plating, a short time‐lag was crucial to obtaining a thin and homogeneous metal layer with strong adhesion. In addition, we demonstrate the affinity of an aramid film for Pd(acac)2. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
30.
SFLAC (state feedback and load acceleration control) is proposed for vibration suppression and disturbance rejection control of a multi-inertia system. A multi-inertia system is the model of a steel rolling mill, a flexible arm, a large-scale space structure, etc., and its control will be an important problem in the future of motion control. The main idea of SFLAC is to control the load acceleration which can be estimated by the state observer including the disturbance estimation. A simple PI speed controller and SFLAC based on the reduction models using two and three inertia moments are designed. The effectiveness of SFLAC is demonstrated showing some simulation results 相似文献