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Induction-motor torque is not accurately controlled when the estimated secondary resistance of an induction-motor model in a vector controller differs from the true secondary resistance. An algorithm which identifies the secondary resistance on-line is developed. The motor operating condition for secondary resistance identification, the stable identifier organization, and the experimental investigation confirming the identification algorithm performance are presented. The algorithm is based on the theory of model reference adaptive systems (MRAS). The proposed algorithm stably identifies the secondary resistance under any load and any speed when a sinusoidal signal is injected into the flux axis primary current. The vector controller adopting this algorithm controls motor torque accurately under any load and any speed. 相似文献
105.
Kameda Atsushi Yamamoto Masahito Uejima Hiroki Hagiya Masami Sakamoto Kensaku Ohuchi Azuma 《Natural computing》2005,4(2):103-126
In this paper, we propose a new architecture for a multi-state DNA machine whose conformation of repeated hairpin structures changes sequentially in response to input oligomers. As an application of the machine, we also propose molecular memory in which the machine is used as a memory unit. Addressing in the memory is realized through state transitions of the machine. We then describe a method for designing DNA sequences of the machine, which exhaustively checks conformational changes of the machine by dividing its secondary structure into hairpin units. The method is based on the minimum free energy of the structure, the structure transition paths, and the total frequency of optimal and suboptimal structures. DNA sequences designed by the method were tested in a chemical experiment in which a machine consisting of two hairpins was actually constructed. As a result, we verified that the multi-state DNA machine realized the expected changes in its secondary structure. 相似文献
106.
Mitsutoshi Miyasaka Hiroyuki Hara Hiroki Takao Simon Tam Rob Payne Prem Rajalingham Satoshi Inoue Tatsuya Shimoda 《Journal of the Society for Information Display》2005,13(3):187-191
Abstract— Thin‐film transistors (TFTs) are field‐effect transistors that can be used to create large‐scale‐integrated (LSI) circuits. The combination of high‐performance TFTs and transfer technology of the TFTs has the potential to foster the rise of a new flexible microelectronics industry. This paper discusses the current status of flexible microelectronics, using a TFT fingerprint sensor (FPS) as an example. Technology used in active‐matrix displays can easily be applied to the TFT FPS. TFT technology should not be confined to the display industry; its use should be expanded into the semiconductor industry. With the result presented in this paper, we declare a new era of flexible microelectronics open. 相似文献
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M Kushiro K Shikata H Sugimoto Y Shikata N Miyatake J Wada M Miyasaka H Makino 《Canadian Metallurgical Quarterly》1998,53(5):1314-1320
Prostacyclin (PGI2) is known to have a relaxative action on vascular smooth muscle, an inhibitory action against platelet activation and neutrophil function. Previous studies showed the preventive effects of PGI2 on lupus nephritis and Thy-1 nephritis, although the mechanism has not been clarified. Glomerular endothelial expression of intercellular adhesion molecule-1 (ICAM-1) is up-regulated in experimental and human glomerular diseases, and is known to facilitate leukocyte infiltration into the glomeruli, which ultimately induces the various glomerular injuries. In the present study, we evaluated the therapeutic effects of PGI2 on a rat model for crescentic glomerulonephritis and investigated its putative mechanism in relation to ICAM-1-mediated leukocyte recruitment. Wistar-Kyoto (WKY) rats were injected with nephrotoxic serum and received continuous intraperitoneal infusion of PGI2. PGI2 dramatically decreased proteinuria (123.0 +/- 18.8 vs. 31.6 +/- 4.5), crescent formation and deposition of fibrinogen in the glomeruli, while the deposition of rabbit IgG, rat IgG and rat C3 along the capillary walls was not changed. Furthermore, intraglomerular expression of ICAM-1 and infiltration of macrophages were significantly suppressed by administration with PGI2. In contrast, influx of CD4 or CD8 positive cells was not altered. The present results suggest that PGI2 shows the preventive effects on experimental crescentic glomerulonephritis by inhibiting intraglomerular coagulation and ICAM-1-mediated macrophage-glomerular endothelial cell adhesive pathway. 相似文献
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We attempted to assess whether pannus volume measured by magnetic resonance imaging (MRI) can be used as an indicator of disease activity in rheumatoid arthritis (RA). Eleven women (mean age 46 yr) with uncontrolled RA were studied for 1 yr. Pannus formation in both hands was quantified using MRI at the start of the study, and at 6 and 12 months thereafter. The volume of enhancing pannus (VEP) was compared with changes in the radiological scores, grip strength, joint tenderness counts, joint swelling counts, erythrocyte sedimentation rate (ESR), and serum C-reactive protein (CRP). Patients were classified into three groups based on VEP changes between 0 and 12 months: unchanged (n = 2), decreased (n = 6) and increased (n = 3). VEP at 6 months and at 12 months differed significantly between the three groups. No statistically significant differences were found between the groups in radiographic scores, physical parameters or laboratory parameters despite the fact that some of these parameters changed in the direction indicated by the changes in VEP. VEP can be used as a new indicator to assess disease activity in individual RA patients and, using this parameter, treatment outcome can be assessed in fewer subjects than with traditional measures. 相似文献
110.
Matsui J Akamatsu K Nishiguchi S Miyoshi D Nawafune H Tamaki K Sugimoto N 《Analytical chemistry》2004,76(5):1310-1315
A molecularly imprinted polymer with immobilized Au nanoparticles (Au-MIP) is reported as a novel type of sensing material. The sensing mechanism is based upon the variable proximity of the Au nanoparticles immobilized in the imprinted polymer, which exhibits selective binding of a given analyte accompanied by swelling that causes a blue-shift in the plasmon absorption band of the immobilized Au nanoparticles. Using adrenaline as the model analyte, it was shown that molecular imprinting effectively enhanced the sensitivity and selectivity, and accordingly, Au-MIP selectively detects the analyte at 5 microM. The combination of molecular imprinting and the Au nanoparticle-based sensing system was shown to be a general strategy for constructing sensing materials in a tailor-made fashion due to wide applicability of the imprinting technique and the independence of the sensing mechanism from the analyte recognition system. 相似文献