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51.
52.
Xing-Zheng Wu Toshiaki Nakaoka Tomomi Inoue Haruo Inoue 《Sensors and actuators. A, Physical》2009,155(2):241-245
Optical sensing of materials movements across a plant surface with a probe beam is reported. It is based on monitoring of deflection of a probe beam passing through a vicinity of the plant surface. The deflection of the probe beam was caused by concentration gradients of chemical species involved in the materials moments in physiological activities of the plant. Typha angustifolia L. was used as a model plant. The beam deflection at different locations of both leaves and roots in respiration process were monitored and compared. It is found that deflection signals changed with time and locations. Experimental results showed that the beam deflection method could be used for noninvasive sensing and monitoring of materials movements across the plant surface. 相似文献
53.
This paper presents a development history of a wearable, scalable vibrotactile stimulus delivery system. This history has followed a path from desktop-based, fully wired systems, through hybrid approaches consisting of a wireless connection from the host computer to a body-worn control box and wires to each tactor, to a completely wireless system employing Bluetooth technology to connect directly from the host to each individual tactor unit. Applications for such a system include delivering vibrotactile contact cues to users of virtual environments, providing directional cues in order to increase situational awareness in both real and virtual environments, and for general information display in wearable contexts. Through empirical study, we show that even a simple configuration, such as eight tactors arrayed around the torso, can be effective in increasing situational awareness in a building-clearing task, compared to users who perform the same task without the added cues. 相似文献
54.
Nakamura Masahiko Suzuki Yutaka Tomoda Haruo 《IEEE transactions on bio-medical engineering》1982,(7):523-530
A quantitative approach for correction of background counts is described for determination of the left ventricular ejection fraction from first-pass radionuclide angiocardiography. First, the method is investigated theoretically and numerically using a mathematical model. It is demonstrated that the ejection fraction can be estimated relatively well, even in a noisy situation. Second, the method is applied to the left ventricular time-activity curves from two different regions of interest, the carefully selected and the laxly selected, and these are compared to each other. Good agreement (correlation coefficient = 0.96) for 20 patients was obtained between the ejection fractions from the carefully selected region of interest and those from the laxly selected one. 相似文献
55.
Generation of free radicals (mechano-radicals) by the milling of alumina powder at 77 K was demonstrated by ESR. After milling of alumina in the presence of ethylene (simultaneous milling) at 77 K, polyethylene-propagating radicals instead of the alumina mechano-radicals were detected by ESR. Also the contact of ethylene with the milled alumina converted alumina mechano-radicals into polyethylene propagating radicals at a temperature above the melting point of ethylene. The products extracted by hot toluene from the simultaneous milling were identified by IR to be polyethylene, and their molecular weights were roughly 10,000. The residues after the extraction were bonded with the alumina. Polypropylene was also produced by a similar method of milling of alumina in the presence of propylene. The obtained polyproylene was atactic, and its molecular weight was about 400. 相似文献
56.
The steady-state flow method has been widely used in the kinetic study of heterogeneous catalysis. Under the conditions of steady state, all elementary steps in series are progressing at the same rate and hence the measured rates hardly tell the precise kinetic structure, or mechanism, of catalytic reactions which usually consist of several elementary steps including adsorption of reactants, surface reaction, and desorption of products. In the kinetic analyses of any given reactions, it is a common practice for the investigator to postulate a number of suspected rate models and then to assess these models to verify a optimal one which best fits observed rate data. Usually, however, there are quite a large number of plausible rate models even for a rather simple reaction, and it is not easy to determine the most adequate model among others even with the help of mathematical model indentification techniques with a electronic computer. This method is based on the assumption that there is a best model which reflects the true mechanism of the reaction sequences among the postulated models. But there is no certification which justifies this assumption. Therefore, even when a rate model is found to fit the rate data very well, the value of parameters appearing in the rate model should be further assessed in regards to their physical significance. 相似文献
57.
Masakazu Ejiri Haruo Yoda Hiroshi Sakou Yuzaburo Sakamoto 《Machine Vision and Applications》1989,2(3):155-166
Combining the knowledge-based processing with image processing is considered a key issue in the future of visual inspection of complex patterns such as multilayered semiconductor wafers. However, present technology restricts this combination, mainly because of the exhaustively long time usually required for each type of processing. To cope with this situation, a unique knowledge-directed image processing method is proposed, in which every image processing step is controlled in real time by parametric knowledge driven by design patterns. The resulting structure of the image processor is a pipeline, in which each piece of knowledge is embodied as a combination of a hardware processing unit and control unit. In this paper the types of knowledge and their implementation are explained, and an inspection machine for logic IC wafers based on this pipelined knowledgedirected image processing is introduced. 相似文献
58.
59.
Eight strains of bacteria which could not grow under aerobic conditions, were isolated from Japanese spiny lobster. All the strains were Gram-positive, non-sporeforming cocci, and grew well under anaerobic conditions. The strains required a decreased oxygen tension rather than an increased CO2 tension. Catalase, oxidase, nitrate reductase and urease were not produced. The strains fermented glucose, cellobiose, trehalose and levulose. Indole and H2S were not produced. Macromolecule substances including starch, esculin, casein, gelatin and chitin were not hydrolyzed. Lactic acid was the sole product from peptone-yeast extract-Fildes solution-glucose broth. Fermentable carbohydrates were not required. The strains could grow at 20 to 37°C, and required NaCl for growth. From the above results, the strains were identified as anaerobic (aerotolerant) Streptococcus sp. 相似文献
60.