http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
EFFECT OF LOAD AND ANODE/CATHODE AREA RATIO ON WEAR OF Zr-ALLOY IN Na₂SO₄ SOLUTION
A. IWABUCHI,K. HOSOYA,K. ABE,T. SHIMIZU,S. S. KIM 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10
In this paper we examined the contribution of mechanical and electrochemical factors in corrosive wear for Zr-alloy against Al₂O₃ ball in Na₂SO₄ solution. Normal load and the area of metallic specimen 'was varied to change the corrosion behavior. At the commence of sliding, the potential drop took place, which increased with load due to the great exposure of fresh surface. Wear volume was linearly proportional to load. The corrosion factor was about 15%. By increasing the Aa/Ac ratio, corrosion factor to total wear decreases and saturates above Aa/Ac=0.15.
Characterization and Generation of Machined Surfaces
M. UCHIDATE,T. SHIMIZU,A. IWABUCHI 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10
In this paper, electrical discharge machined (EDM) surfaces machined with various machining parameters are characterized and simulated. Three-dimensional surface topography of EDM surfaces are measured by a stylus instrument. Surface topography is characterized with auto-correlation coefficient and height probability density functions. Then, EDM surfaces are modeled and computer-simulated by using the non-causal 2-D auto-regressive model. Simulation results show that EDM surfaces are characterized well by a few parameters.
Kanaya, Y.,Irie, H.,Takashima, H.,Iwabuchi, H.,Akimoto, H.,Sudo, K.,Gu, M.,Chong, J.,Kim, Y. J.,Lee, H.,Li, A.,Si, F.,Xu, J.,Xie, P.-H.,Liu, W.-Q.,Dzhola, A.,Postylyakov, O.,Ivanov, V.,Grechko, E.,Ter Copernicus GmbH 2014 Atmospheric Chemistry and Physics Vol.14 No.15
<P>Abstract. We conducted long-term network observations using standardized Multi-Axis Differential optical absorption spectroscopy (MAX-DOAS) instruments in Russia and ASia (MADRAS) from 2007 onwards and made the first synthetic data analysis. At seven locations (Cape Hedo, Fukue and Yokosuka in Japan, Hefei in China, Gwangju in Korea, and Tomsk and Zvenigorod in Russia) with different levels of pollution, we obtained 80 927 retrievals of tropospheric NO2 vertical column density (TropoNO2VCD) and aerosol optical depth (AOD). In the technique, the optimal estimation of the TropoNO2VCD and its profile was performed using aerosol information derived from O4 absorbances simultaneously observed at 460-490 nm. This large data set was used to analyze NO2 climatology systematically, including temporal variations from the seasonal to the diurnal scale. The results were compared with Ozone Monitoring Instrument (OMI) satellite observations and global model simulations. Two NO2 retrievals of OMI satellite data (NASA ver. 2.1 and Dutch OMI NO2 (DOMINO) ver. 2.0) generally showed close correlations with those derived from MAX-DOAS observations, but had low biases of up to ~50%. The bias was distinct when NO2 was abundantly present near the surface and when the AOD was high, suggesting a possibility of incomplete accounting of NO2 near the surface under relatively high aerosol conditions for the satellite observations. Except for constant biases, the satellite observations showed nearly perfect seasonal agreement with MAX-DOAS observations, suggesting that the analysis of seasonal features of the satellite data were robust. Weekend reduction in the TropoNO2VCD found at Yokosuka and Gwangju was absent at Hefei, implying that the major sources had different weekly variation patterns. While the TropoNO2VCD generally decreased during the midday hours, it increased exceptionally at urban/suburban locations (Yokosuka, Gwangju, and Hefei) during winter. A global chemical transport model, MIROC-ESM-CHEM (Model for Interdisciplinary Research on Climate-Earth System Model-Chemistry), was validated for the first time with respect to background NO2 column densities during summer at Cape Hedo and Fukue in the clean marine atmosphere. </P>
THE INFLUENCE OF AFFECTED LAYER OF EDM ON THE WEAR CHARACTERISTICS OF CEMENTED TUNGSTEN CARBIDE
K. ISHIKAWA,A. IWABUCHI,T. SHIMIZU 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10
This paper describes the wear characteristics of WC-Co cemented carbides machined with Wire-cut or Die-sinking EDM. We prepared the specimens with different grades of grinding to remove the affected layer after the EDM. These specimens were experimented by block-an-cylinder type tribometer. The result indicated that although the hardness of the affected layer was lower than that of the bulk, wear resistance was increased. In order to investigate the cause of the increase in wear resistance of the affected layer, the layer was observed and analyzed by SEM and ESCA. We also discussed the mean free path of Co phase.
M. UCHIDATE,T. SHIMIZU,A. IWABUCHI 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10
In this paper, the relationship among the 3-D surface topography parameters are studied. Several surface topography parameters that are important in tribology are calculated against various surface topography data. 3-D surface data with desired properties are generated by using the non-causal 2-D auto-regressive (AR) model. The non-causal 2-D AR model is a random 3-D surface topography model that can generate 3-D surface topography data with specified parameters.
GENERATION OF THREE DIMENSIONAL SUREACE TOPOGRAPHY USING NON-CAUSAL TWO DIMENSIONAL AR MODEL
UCHIDATE, M.,SHIMIZU, T.,IWABUCHI, A. ENGINEERING TRIBOLOGY RESEARCH INSTITUTE KYUNGPOOK 2000 INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE OF TRI Vol.2000 No.-
In this paper, a generation procedure of 3-D surface topography data with specified parameters using non-causal 2-D AR(auto-regressive) model is described. The aim of this study is to establish generation procedure of 3-D surface topography for numerical simulations that deal with random surface topography directly and contribute to surface topography design. AR model can express surface topography as linear weighted summation of surface topography itself. Non-causal 2-D AR model is an advanced model of causal 2-D AR model used in previous researches. AR parameters are estimated by algorithm of least squares and height distribution of the surface generated by 2-D AR model is modified by Johnson transformation. Parameters of spectral property and height distribution are required to generate 3-D surface topography. Several sets of 3-D surface topography with specified parameters are generated with the proposed method and evaluated against some surface parameters.
Numerical Simulation of Tribological Phenomena Using Stochastic Models
T. SHIMIZU,M. UCHIDATE,A. IWABUCHI 한국트라이볼로지학회 2002 한국트라이볼로지학회 학술대회 Vol.2002 No.10
Tribological phenomena such as wear or transfer are influenced by various factors and have complicated behavior. Therefore, it is difficult to predict the behavior of the tribological phenomena because of their complexity. But, those tribological phenomena can be considered simply as to transfer micro material particles from the sliding interface. Then, we proposed the numerical simulation method for tribological phenomena such as wear or transfer using stochastic process models. This numerical simulation shows the change of the 3-D surface topography. In this numerical simulation, initial 3-D surface roughness data are generated by the method of non-causal 2-D AR(autoregressive) model. Processes of wear and transfer for some generated initial 3-D surface data are simulated. Simulation results show successfully the change of the 3-D surface topography.