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31.
We present three-dimensional profilometry based on triangulation in which a hexagonal pattern is projected on the object. To obtain an accurate result with a one-shot photographic image, the Fourier transform method and method of excess fraction are adopted. The three grating components of the hexagonal pattern are used. For compactness a new pattern projection scheme is introduced. The experimental results show that the constructed optical system works well for measuring the profile of a mannequin with a height resolution of ~ +/- 1 mm. 相似文献
32.
33.
Ken -ichi Maruya Kazumi Ito Kazuhito Kushihashi Yoshiho Kishida Kazunari Domen Takaharu Onishi 《Catalysis Letters》1992,14(1):123-126
The CO-H2 reaction over CeO2 catalysts at around 623 K and 67 kPa forms isoprene with about 20% and 70% selectivities in total and C5 hydrocarbons, respectively. The formation of dienes may be due to the low and high activity of CeO2 for alkene and CO hydrogenation, respectively. 相似文献
34.
A new anatase phase of photoactive Ti1?2XNbXScXO2 (X = 0–0.2) solid solutions was directly formed as nanoparticles from precursor solutions of TiOSO4, NbCl5, and Sc(NO3)3 under mild hydrothermal conditions at 180 °C for 5 h using the hydrolysis of urea. With the increase of the content of niobium and scandium from X = 0 to 0.2, the lattice parameters a0 and c0, the crystallite size, and the optical band gap of anatase gradually increased. Their photocatalytic activity and adsorptivity were evaluated separately by the measurement of the concentration of methylene blue (MB) remained in the solution in the dark or under UV-light irradiation. The anatase-type Ti1?2XNbXScXO2 (X = 0.05) showed approximately two times and three times as high photocatalytic activity as those of the hydrothermal anatase-type pure TiO2 and commercially available reference pure TiO2 (ST-01), respectively. The anatase phase of Ti1?2XNbXScXO2 (X = 0–0.2) existed stably up to 900 °C during heat treatment in air. New rutile-type Ti1?2XNbXScXO2 solid solutions are formed through the phase transformation. The starting temperature of anatase-to-rutile phase transformation for Ti1?2XNbXScXO2 (X = 0–0.2) solid solutions was delayed but its completing temperature was accelerated. 相似文献
35.
Kenji Fujisawa Kazuya Akita Naoyuki Fukuda Kumiko Kamada Takaharu Kudoh Go Ohe Takamitsu Mano Kanji Tsuru Kunio Ishikawa Youji Miyamoto 《Journal of materials science. Materials in medicine》2018,29(8):121
Carbonate apatite (CO3Ap) is an inorganic component of bone. This study aimed to compare the composition and tissue response to of CO3Ap (CO3Ap-DP) fabricated by the dissolution–precipitation reaction using calcite as a precursor and Bio-Oss®, which is widely used in orthopedic and dental fields as a synthetic bone substitute. X-ray diffraction and Fourier transform infrared results showed that CO3Ap-DP and Bio-Oss® were both B-type carbonate apatite with low crystallinity. The average sizes of CO3Ap-DP and Bio-Oss® granules were 450?±?58 and 667?±?168μ?m, respectively, and their carbonate contents were 12.1?±?0.6 and 5.6?±?0.1?wt%, respectively. CO3Ap-DP had a larger amount of CO3 than Bio-Oss® but higher crystallinity than Bio-Oss®. When a bone defect made at the femur of rabbits was reconstructed with CO3Ap-DP and Bio-Oss®, CO3Ap-DP granules were partially replaced with bone, whereas Bio-Oss® remained at 8 weeks after implantation. CO3Ap-DP granules elicited a significantly larger amount of new bone formation at the cortical bone portion than Bio-Oss® at 4 weeks after the implantation. The results obtained in the present study demonstrated that CO3Ap-DP and Bio-Oss® showed different behavior even though they were both classified as CO3Ap. The CO3 content in CO3Ap played a more important role than the crystallinity of CO3Ap for replacement to bone and high osteoconductivity. 相似文献
36.
This paper presents a control scheme of three‐phase to three‐phase matrix converters for reducing the number of commutations. The number of commutations during a control period in the proposed control scheme can be reduced to three from four in the conventional control scheme. It can be realized by using the output currents in the calculations of the duty factors. As a result, one of the output line voltage waveforms during a control period consists of two voltage levels with the same sign of the reference. The switching loss and the output voltage harmonics can be reduced. The effectiveness of the proposed control algorithm of the matrix converters has been verified by experiments. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(2): 60–69, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20824 相似文献
37.
Yvan Antonio LlaveTomoaki Hagiwara Takaharu Sakiyama 《Journal of food engineering》2012,109(3):553-560
An artificial neural network (ANN) model was developed for prediction of the cold spot temperature profile during retort processing using starch dispersion (STD) as a model food. STDs of different concentrations were prepared by mixing corn starch powder with distilled water at 90 °C for 30 min. Each of the partially gelatinized STDs thus prepared was filled in retort pouches and processed in a retort under various combinations of holding temperature, holding time, and rotational speed. Thermocouples were inserted into selected pouches one by one to monitor the cold spot temperature at regular intervals. The profiles of cold spot temperature together with retort temperature thus obtained were served to ANN modeling as training or validation data. Back-propagation network was chosen as the network model. Input variables for the model were current and past temperatures of the cold spot (Tn, Tn−1, and Tn−2) and current retort temperature θn and current time tn. Output was the temperature of the cold spot at the next time step Tn+1. A model with 2 hidden layers, which contained 11 and 15 nodes, respectively, was the best among the models tested. Using the model developed, prediction of a whole profile of the cold spot temperature was tested, starting from temperature data of the first three time steps with a whole profile of retort temperature monitored. The results showed very good performance of the model, relative errors for F0 value prediction being less than 2%. 相似文献
38.
Toshio Terasaki Takaharu Fukikawa Takanori Kitamura Tetsuya Akiyama 《Welding International》2013,27(11):830-838
Multilayer welding is considered to be an accumulation of two-pass welding, and it was clarified that the basic factors of welding deformation were produced by two-pass welding. From comparison between the experimental results and numerical analysis, it was found that the numerical analysis method used in this research was very accurate to predict the welding deformation. Also, the influences of the welding heat input and the distance between two-passes on the welding deformation were examined by using the numerical analyses. As a result, it was found that the longitudinal shrinkage made from each pass was decided by the inherent strain distribution parallel to the weld line. The inherent strain distribution parallel to the weld line after two-pass welding was a larger value at one- or two-pass welding. On the other hand, it was revealed that transverse shrinkage made from each pass was decided by the integration of inherent strain distribution perpendicular to the weld line. In the case of the inherent strain distribution perpendicular to the weld line after two-pass welding, it was clarified that the inherent strain was almost same as the sum of inherent strain distribution perpendicular to the weld line made from each pass. 相似文献
39.
This paper presents a control scheme for matrix converters for reducing the output voltage harmonics. The proposed control scheme is based on the direct AC/AC conversion approach and the carrier‐based PWM control to obtain the constant switching frequency. The proposed scheme can achieve simultaneous control of both the output voltage and the input power factor. A feature of the proposed control scheme is the reduction of both the output voltage harmonics and the number of instances of commutations. The effectiveness of the proposed control algorithm for a matrix converter has been verified by simulations. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(2): 61–72, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20550 相似文献
40.
Takaharu Takeshita Yuji Hayashi Nobuyuki Matsui Hideki Fujita 《Electrical Engineering in Japan》2001,136(3):39-48
This paper presents a method of amplitude control and unbalance compensation of the load voltage using a series–shunt power converter. The series power converter works to obtain a constant balanced sinusoidal load voltage. The shunt converter regulates the DC link voltage and compensates for the reactive current of the source within the rated current of the converter. To design the required capacity for the series–shunt power converter, the relation between the converter capacity and the load power factor at constant compensation voltage is introduced. The required capacity of the series–shunt power converter is reduced by more than 50% compared with that of a conventional series power converter. The effectiveness of the proposed load voltage compensation technique using the series–shunt power converter is verified by experiments. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 39–48, 2001 相似文献