Journal of the Japanese Society for Experimental Mechanics
Print ISSN : 1346-4930
ISSN-L : 1346-4930
Volume 15 , Issue 1
Showing 1-7 articles out of 7 articles from the selected issue
Original Papers
  • -Micro-bubbles Ozonation Technology-
    Shunsaku YAGI, Shigeakira SAITO
    2015 Volume 15 Issue 1 Pages 19-23
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       As an useful advanced technology, ozone is rapidly introduced in the field of water and wastewater treatment due to its high oxidizing ability. In the present study, for the purpose of improving ozonation efficiency by applying micro-bubbles technology, characteristics of ozone dissolution and pharmaceuticals decomposition phenomena were analyzed and evaluated. From lab-scale micro-bubbles ozonation experiments, it was found that ozone micro-bubbles had high overall convective mass transfer coefficients due to its extensive gas-liquid interfacial area and had superior ozone dissolution ability under high temperature conditions. Secondly, pharmaceuticals having high decomposition rates were presumed to be hydrophilic, and micro-bubbles ozonation had high decompositions coefficients as for Acetaminophen.
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  • Manabu IGUCHI, Yusuke SAKAI, Tomoya NAKAJIMA, Moriyoshi SHITARA, Yos ...
    2015 Volume 15 Issue 1 Pages 24-29
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       Gas injection is commonly used for agitating a molten metal bath in the refining processes such as the AOD process. Many water model experiments have been carried out to find out efficient injection methods. In the current processes gas is injected under steady state condition. The purpose of this study is to experimentally investigate the possibility of efficiency enhancement by unsteady gas injection. A J-shaped lance is used for intermittent air injection into a cylindrical water bath. The amplitude of the deep-water wave type of swirl motion is measured using a digital camera. The measured value of the amplitude became smaller than that observed under the steady gas injection.
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  • Tsutomu OKUBO, Masanobu TAKAHASHI, Kengo KUBOTA, Hideki HARADA, Masate ...
    2015 Volume 15 Issue 1 Pages 30-37
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       Down-flow hanging sponge (DHS) reactor has been developed mainly for sewage treatment in developing countries. The novel rector employs polyurethane sponge material as support media, which promises a proliferation of a large amount of biomass, and thus an excellent capability of removing pollutants. The characterization of the three types of sponge support media is conducted in respect of water flow and oxygen uptake ability. Water was supplied to the device which consisted of 40 sponge media connected in series, and then tracer experiment was carried out. The ratios of actual hydraulic retention time (HRT) per theoretical HRT were in the range of 25-67% depending on the type of support media, meaning that short circuit flow occurs in this type of reactor. By supplying deoxygenized water from the top of the device, overall volumetric oxygen transfer coefficient, KLa, was evaluated. In spite of the non-aerated conditions, the KLa values were so high, 0.56-4.88 (1/min), surpassing those of other mechanically aerated aerobic processes. Furthermore, it was found that the suspended solids (SS) concentration in the influent played a role to increase the ratio of actual HRT/theoretical HRT, meaning that management of the influent SS concentration is prerequisite for preventing the clogging problem in the DHS.
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  • Akihiro TAKAHASHI, Naoyuki YAMAMOTO, Toshinobu TOYOHIRO
    2015 Volume 15 Issue 1 Pages 38-44
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       The Shielded metal arc welding is mostly popular for fused injection method of metal to metal. The spatter particle of various sizes appears during the metal arc welding, and then adheres so strongly on the surface of welded plate. In general, the commercial spatter adhesion preventive agent is coated on the surface of plate before welding. However, the agent from artificial organic synthesis has several problem, such as influence of global environmental and human health, stink and expensive. The purpose of this study is to develop the new welding spatter adhesion preventive agent made of water, flour powder and honey, which brings the environmental merit, no stink and low cost. Effective contents among water, flour and honey was confirmed by sensory evaluation test and experimental observation after welding. The results of tensile inspection test of a butt welded specimen of SS400 and hydrogen analysis by JIS Z3118 satisfied welded strength and the reliability of welding. Anti-adhesive mechanism was discussed based on heat characteristics and observation of boundary between spatter and surface of welded plate. Another combinations as grain or starch powder and syrup with spatter anti-adhesive effect were also described.
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  • Khalid ALMAYMAN, Satoru YONEYAMA
    2015 Volume 15 Issue 1 Pages 51-57
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       In this paper, digital image correlation and a multi-view imaging system are being used to reconstruct 3D shapes of different parts of the human face and then aligning these parts using the Iterative Closest Point (ICP) algorithms to produce the full 3D shape of the human face. In addition, strain measurements on the surface of the skin that are caused by a facial expression are measured. The apparatus for the proposed method is environmentally friendly and consists mostly of camera equipment. The experiment apparatus and set up are, seven DSLR cameras that are mounted on a half circle light metal pipe, using camera clamps. In order to facilitate mobility and height adjustments, the half a circle frame is mounted on three tripods. A practical method for calibrating this system is done by using the designed double sided calibration board, with check marks on both sides that are aligned with each other and fitted into a photo frame which can be mounted on any standard tripod. A safe and practical method to apply a random speckle pattern on a human' s face is utilized by using an air brush make up set. Finally, the standard deviation of the matched points with respect to the template points are calculated.
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  • Takuma MATSUO, Asuka HASEYAMA
    2015 Volume 15 Issue 1 Pages 58-63
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       In order to detect degradation in golf balls, degradation mechanism in golf ball was investigated and ultrasonic testing technique was applied to evaluate degradation in golf balls. Degradation mechanism of golf ball was first studied during water, high temperature and high temperature with high humidity environment. Degradation was evaluated by using restitution test, indentation test and compression test. Coefficient of restitution and hardness were rapidly changed in high temperature with high humidity environment, respectively. Hardness of the cover increased with increasing test time and hardness of core decreased with increasing test time. There was good relationship between change in hardness of cover and compression stiffness that detected in compression test in the balls used in this study. Ultrasonic testing was next applied. Change in arrival time of symmetrical mode wave that was propagated in the cover was corresponded to the change of hardness in the cover. Thus, degradation of the golf ball was roughly estimated by using ultrasonic technique in this case.
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  • Masaru ONODERA, Kensuke KAGEYAMA
    2015 Volume 15 Issue 1 Pages 64-68
    Published: April 13, 2015
    Released: April 13, 2015
    JOURNALS FREE ACCESS
       Electret condenser sensor with PFA film lamination using silica-agglomerates electret (FilmECS) demonstrates an excellent flexibility and low acoustic impedance compared with piezoelectric sensors. The dual sensors were prepared by lamination of the two FilmECS elements for measurement of a contact pressure and a hardness of soft material. The peak voltage Vp of the transmitting and receiving waveform was related to the contact pressure when the dual sensor was placed on the several soft materials. Furthermore, as the dual sensor was placed on softer material, higher attenuation of the waveform was observed. Eventually, the hardness of the tested materials was related to the centroid frequency of the waveform fc which was calculated from the FFT spectrum from 0.1 to 100 kHz. These results indicate that the dual sensor using FilmECS elements could be used for measurement of the contact pressure and the hardness of soft materials.
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