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61.
An on-line recognition method for hand-written characters utilizing stroke vector sequences and a positional vector sequence has been developed. The number of target characters is about 2000, and fairly good recognition scores have been attained. Our scheme uses the number of strokes as the primary parameter. We employ three types of recognition strategy depending on the number of strokes. The general stroke vector sequence method, devised to analyze the shape, can represent both skeleton and local characteristics by a small amount of information; and the restricted dynamic programming method is effective to determine the shape of a stroke. The similarity of two shapes and the complexity of a stroke have been introduced to reduce the dictionary size and the processing time, respectively.  相似文献   
62.
An ultrasonic linear motor using ridge-mode traveling waves   总被引:1,自引:0,他引:1  
A new type of ultrasonic linear motor is presented using traveling waves excited along a ridge atop a substrate. The ridge cross section was designed to permit only the fundamental mode to be excited during operation of the motor, with a Langevin transducer used as the source of vibration in this study. The ridge waveguide was first made of lossy media to avoid reflecting vibration energy back toward the vibration source, forming a traveling wave. A 5-mm-wide, 15-mm-tall rectangular acrylic ridge was used to move a slider placed upon it toward the vibration source, in opposition to the direction of the traveling wave transmitted along the waveguide ridge. Using a low-loss 3 x 6-mm aluminum rectangular ridge combined with a damper clamped onto the far end of the waveguide, similar results were obtained. To obtain bidirectional operation, the damper was replaced with a second Langevin transducer, giving a pair of transducers located perpendicularly to the ends of the ridge and driven with an appropriate phase difference. The moving direction of the slider was reversed by shifting this phase difference by about 180 degrees. With this simple configuration, it may soon be possible to fabricate a linear micromotor system on a silicon substrate or other semiconductor wafer adjacent to other electronic and optoelectronic devices.  相似文献   
63.
Highly active catalysts for the reduction of nitric oxide with ammonia can be obtained by supporting vanadium oxide, more than 15% by weight, on a silica gel with micropores of a mean diameter larger than 10 nm, followed by calcining it in the temperature range from 250 to 350°C. Both pre-impregnation with a small amount of titania and addition of ammonium bromide increased the activity markedly. The catalyst gave an NO conversion level of 100% at 150°C. A series of life tests of the catalysts, which was performed at 230°C using a simulated flue gas containing 700 parts/106 of sulphur dioxide, demonstrated that their activities were stable for more than 300 h. Little irreversible change in the catalyst properties was observed after the test.  相似文献   
64.
65.
The exfoliation of layered muscovite with non-swelling property has been performed by combining various processes, such as heating, intercalation, and wet-jet milling. The c axis of muscovite was expanded from 2004.0 to 2022.8 pm at 800 °C without the destruction of crystallinity of muscovite. The heating at 800 °C led to the weak attraction force between potassium ions and silicate layers by hydroxylation of muscovite. The muscovite heated at 800 °C progressed the intercalation of dodecylammonium chloride (DDAC) into the layers effectively. Furthermore, the DDAC molecules were inserted to the interlayer of muscovite effectively by suppressing the formation of micelle of DDAC. The sedimentation test of wet-jet milled muscovite slurry showed that the relative packing density of muscovite was decreasing with increasing the amount of the intercalated DDAC. As results, the aspect ratio of muscovite prepared with combining the heating, the intercalation and the wet-jet milling was increased by 253% as compared to the raw muscovite. The aspect ratio was calculated from laser particle size distribution and thickness size distribution which was estimated from field emission-scanning electron microscopic images. The expansion of the interlayer led to the effective exfoliation of muscovite with high aspect ratio.  相似文献   
66.
The bulk synthesis of fluorescent colloidal SU‐8 polymer rods with tunable dimensions is described. The colloidal SU‐8 rods are prepared by shearing an emulsion of SU‐8 polymer droplets and then exposing the resulting non‐Brownian rods to ultrasonic waves, which breaks them into colloidal rods with typical lengths of 3.5–10 µm and diameters of 0.4–1 µm. The rods are stable in both aqueous and apolar solvents, and by varying the composition of apolar solvent mixtures both the difference in refractive index and mass density between particles and solvent can be independently controlled. Consequently, these colloidal SU‐8 rods can be used in both 3D confocal microscopy and optical trapping experiments while carefully tuning the effect of gravity. This is demonstrated by using confocal microscopy to image the liquid crystalline phases and the isotropic–nematic interface formed by the colloidal SU‐8 rods and by optically trapping single rods in water. Finally, the simultaneous confocal imaging and optical manipulation of multiple SU‐8 rods in the isotropic phase is shown.  相似文献   
67.
ABSTRACT

This paper presents a robust bin-picking system utilizing tactile sensors and a vision sensor. The object position and orientation are estimated using a fast template-matching method through the vision sensor. When a robot picks up an object, the tactile sensors detect the success or failure of the grasping, and a force sensor detects the contact with the environment. A weight sensor is also used to judge whether the lifting of the object has been successful. The robust and efficient bin-picking system presented herein is implemented through the integration of different sensors. In particular, the tactile sensors realize rope-shaped object picking that has yet to be made possible with conventional picking systems. The effectiveness of the proposed method was confirmed through grasping experiments and in a competitive event at the World Robot Challenge 2018.  相似文献   
68.
Lead supported on active carbon showed a catalytic activity for the vapor phase carbonylation of methanol under pressurized conditions in the presence of methyl iodide promoter.  相似文献   
69.
We investigated the sound absorption characteristics of an organic hybrid material comprised of chlorinated polyethylene (CPE) as the matrix polymer and N,N′‐dicyclohexyl‐2‐benzothiazolyl sulfenamide (DBS) as the second component of an organic low‐molecular‐weight compound. We found specific crystallites, obtained by annealing, that generated new absorption for a low‐frequency sound in a CPE/DBS blend. We observed two sound absorption peaks, around 300 and 1000 Hz, in the annealed CPE/DBS (50 : 50 w/w) blends, whereas those peaks were not observed in the untreated sample. There were two kinds of crystals with different melting points in the annealed samples. It was confirmed that the crystals with the lower melting point brought about sound absorption at a low frequency. The crystals that had the lower melting point were smaller and/or more disordered than the crystals that had the higher melting point. We calculated the fraction of these two types of crystals from differential scanning calorimetry and wide‐angle X‐ray diffraction measurements. The annealing or reannealing temperature specified the fraction of the crystal with the lower melting point, and the obtained crystal fraction characterized sound absorption frequency. Therefore, it is possible to control the sound absorption frequency of an organic hybrid by heat treatment such as annealing. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006  相似文献   
70.
Three lipases, isolated previously in our laboratory, and a known lipase fromCandida cylindracea were screened for the enrichment of arachidonic acid (AA). The enzyme fromC. cylindracea was the most effective for the production of oil with high concentration of AA. When a single-cell oil fromMortierella alpina, containing 25% AA, was hydrolyzed with this lipase for 16 h at 35°C, the resulting glycerides contained 50% AA at 52% hydrolysis. After this, no further hydrolysis occurred, even with additional lipase. However, when the glycerides were extracted from the hydrolyzate and were hydrolyzed again with new lipase, the resulting oil contained 60% AA, with a recovery of 75% of its initial AA content. Triglycerides were the main components of the resulting oil. The release of each fatty acid from the oil depended on the hydrolysis rate of its ester. The fatty acid, whose ester is the poorest substrate for the enzyme, is concentrated in the glycerides.  相似文献   
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