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141.
Marimin M. Umano M. Hatono I. Tamura H. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2002,32(5):691-700
Gradual improvements to a single-level semi-numeric method, i.e., linguistic labels preference representation by fuzzy sets computation for pairwise fuzzy group decision making are summarized. The method is extended to solve multiple criteria hierarchical structure pairwise fuzzy group decision-making problems. The problems are hierarchically structured into focus, criteria, and alternatives. Decision makers express their evaluations of criteria and alternatives based on each criterion by using linguistic labels. The labels are converted into and processed in triangular fuzzy numbers (TFNs). Evaluations of criteria yield relative criteria weights. Evaluations of the alternatives, based on each criterion, yield a degree of preference for each alternative or a degree of satisfaction for each preference value. By using a neat ordered weighted average (OWA) or a fuzzy weighted average operator, solutions obtained based on each criterion are aggregated into final solutions. The hierarchical semi-numeric method is suitable for solving a larger and more complex pairwise fuzzy group decision-making problem. The proposed method has been verified and applied to solve some real cases and is compared to Saaty's (1996) analytic hierarchy process (AHP) method. 相似文献
142.
Mizuno-Matsumoto Y Okazaki K Kato A Yoshimine T Sato Y Tamura S Hayakawa T 《IEEE transactions on bio-medical engineering》1999,46(3):271-279
The main objectives of the preoperative evaluation of a patient with medically intractable epileptic seizures are localization of the foci and propagation of the epileptiform discharges. Electrocorticographic (ECoG) data of intractable focal epilepsy were analyzed using an AR model, wavelet analysis, and cross-correlation analysis. In order to derive the time-shifts, the cross correlations of the epileptiform discharges were calculated between electrodes for every unit of time. Further analyses were made by means of a set of contour maps of the time-shifts and sequential two- and three-dimensional visualizations of the time-shift maps in order to localize the epileptic foci and study their propagation process. Two types of foci and propagation were revealed in the results. In the first type, epileptiform discharges were generated at localized focal sites and spread quickly to other sites. In the second type, the foci of epileptiform discharges, which appeared soon after the former bursts, were localized at more than one site, and the discharges tended to spread more slowly. The findings suggest that epileptic phenomena can be caused by at least two kinds of mechanisms in one patient: in the former, the propagation might be mediated through synaptic projections, while in the latter, the extracellular diffusion of an excitatory factor might play an important role. In addition, our newly developed visualization technique for the localization of epileptic foci and the propagation of epileptiform discharges should prove useful in the study of epileptogenesis etiology. 相似文献
143.
Teruhiko Akazawa Hiroshi Ikeda Norihiko Ozawa Hideki Kouno Ryozo Yoshizaki 《Journal of Low Temperature Physics》1999,117(5-6):1235-1239
In order to investigate a relationship between the carrier concentration and negative magnetoresistance in the underdoped region, we have performed out-of-plane electrical resistivity measurements for underdoped Bi
2
Sr
1.6
La
0.4
CuO
6+
single crystals. Giant negative magnetoresistance has been observed in the most abundant carrier sample with = 0.12 in our experiment. The negative magnetoresistance reduces with decreasing carrier concentration. 相似文献
144.
Kazuya Tamura 《Chemical engineering science》2006,61(17):5818-5826
Crystallization of calcium carbonate using a gas (CO2)-liquid (Ca(OH)2) reaction was conducted using a three-stage column crystallizer. In this study, the staging effect of the multistage column crystallizer and the effect of the operating parameters on the particle size distribution were experimentally and theoretically investigated. From an economic viewpoint, the multistage column crystallizer has been developed to replace a cascade of MSMPR crystallizers, which requires a large installation area and high operating cost because some crystallizers are connected in a series. In the multistage column crystallizer, a narrower particle size distribution was obtained compared to that obtained in the standard column crystallizer. The theoretical approach to predict the particle size distribution is based on the population balance equation which takes account of the back flow into the crystallizer. The calculation results of particle size distribution fairly coincide with the experimental results, which indicates the particle size distribution in the multistage column crystallizer can be roughly predicted by this theoretical model. 相似文献
145.
146.
Toshihiro KondoKazuhisa Tamura Masamitu TakahasiJun-ichiro Mizuki Kohei Uosaki 《Electrochimica acta》2002,47(19):3075-3080
A newly designed spectroelectrochemical cell was constructed for surface X-ray scattering (SXS) to study single crystal electrodes. Electrochemical characteristics of a specific face of a single crystal electrode can be investigated in the meniscus mode, and SXS measurement can be easily carried out using the spectroelectrochemical cell. The usefulness of the present cell was demonstrated by studying the electrochemical deposition of thin Pd layers on Au(111) and Au(100) that require precise amounts of Pd deposits. 相似文献
147.
K Sakizono T Oita Y Shibata A Tamura S Kasakura 《Canadian Metallurgical Quarterly》1998,46(9):936-941
PIVKA-II is well known as a tumor maker of hepatocellular carcinoma (HCC). We measured serum PIVKA-II concentrations with a commercially available PIVKA-II immunoassay kit (Picolumi PIVKA-II: Eisai Co., Ltd., Tokyo) using Electrochemiluminescence Immunoassay (ECLIA). ECLIA system is a novel immunoassay system using a Ruthenium (II) Tris (bipyridyl) luminesced by electric energy. Cut off value was 40 mAU/ml by receiver-operating characteristic curves as a tumor maker for HCC. Eighty-nine out of 142 (62.2%) patients with HCC had elevated serum PIVKA-II levels and seventeen out of 36 (47.2%) patients whose tumor size was below 2 cm in diameter showed high PIVKA-II levels. We determined the serial changes in serum PIVKA-II levels of two patients with HCC following initial therapy. In these patients, elevations of serum PIVKA-II levels determined by ECLIA system preceded the HCC relapse detected by imaging diagnostic procedures. In summary, this assay system is suitable for detecting small increases in PIVKA-II concentrations. Determination of PIVKA-II by this assay system is found to be useful for the early detection of HCC. 相似文献
148.
A hierarchical command structure and separate drafting and display files allow ease of use and quick response in this 2-D drawing system. 相似文献
149.
H Tsushima S Kawata S Tamura N Ito Y Shirai S Kiso Y Imai H Shimomukai Y Nomura Y Matsuda Y Matsuzawa 《Canadian Metallurgical Quarterly》1996,110(2):375-382
BACKGROUND & AIMS: Contribution of transforming growth factor beta 1 (TGF-beta 1) to tumor progression has been suggested. However, little is known about the role of TGF-beta 1 in colorectal cancer. Plasma TGF-beta 1 levels and its expression were analyzed in patients with colorectal cancer. METHODS: Plasma TGF-beta 1 levels were measured in 22 patients with colorectal cancer using a TGF-beta 1 enzyme-linked immunosorbent assay. Expression of TGF-beta 1 messenger RNA and immunohistochemical distribution of the protein in colorectal cancer tissues were examined. RESULTS: Plasma TGF-beta 1 levels in patients with colorectal cancer (14.8 +/- 8.4 ng/mL) were significantly higher than in normal controls (1.9 +/- 1.4; n = 22) (P < 0.001). After curative surgical resection, plasma TGF-beta 1 levels decreased in examined patients from 11.9 +/- 6.7 to 3.8 +/- 1.2 ng/mL (P < 0.01). TGF-beta 1 messenger RNA was about 2 1/2 times more abundant in colorectal cancer tissues than in control (P < 0.01). TGF-beta 1 was detected in the cytoplasm of colorectal cancer cells immunohistochemically. Both TGF-beta 1 messenger RNA expression in colorectal adenocarcinoma tissues and its plasma levels were associated with tumor stage of Dukes' classification (P < 0.05). CONCLUSIONS: These results suggest that plasma TGF-beta 1 levels may reflect overexpression of the gene in colon cancer tissues and are associated with disease progression. 相似文献