• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.966-968
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• 1992

We have done the insulation diagnostic test of generators in domestic five power plants since 1987 and tested A.C. current increasing rate($\Delta$I), $\Delta$tan$\delta$ and partial discharge in generator winding insulation. This study is described the correlation between nondestructive result(A.C. current increasing rate, $\Delta$tan$\delta$ and partial discharge) and lapse of time in generators.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.2
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• pp.26-32
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• 2010

This paper reports some experimental result in grinding and polishing of silicon cathodes used in semiconductor manufacturing process. Cup shape diamond core wheels were used in experiments and the radial and tangential grinding forces were measured with surface roughness. In polishing experiments, flat type and donut type wool polishing tools were tested. The experimental results indicate that the grinding forces are proportional to the material removal rates and the surface roughness are inversely proportional to the spindle speed. The surface roughness of polished Si decreases with polishing time and higher spindle speed.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1658-1662
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• 2007

The tire uneven wear has been an ongoing concern for a long time, and one of customer's complaints too. This paper deals with uneven wear improvement of passenger car tires, to have tested the tire wear levels by each wheel alignment set (according to changing toe and camber) using taxis. The pre-set wheel alignments on test vehicle were gained by energy friction simulation of tire. The result of this experiment was as follows : First, verified the effects of initial wheel alignment (adjusted at Curb Vehicle Weight) to minimize tire uneven wear. Second, tire uneven wear makes tire life much shorter than even wear does.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1129-1132
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• 1995

Recently, the concept of automation is widely in shipping and unloading materials using the overhead crane for the enhanced productivity. In this regards, we designed an overhead crane that can be operated by operated by computer control system and installed this system at KAERI. In this paper, we introduce algorithms to find the 3D position, diameter, width, and rotated angle of objects such as drum, coil, and container. And the performance of the presented algorithms is tested using drum and container. The result will be useful for positoning grapple device such as spreader to objects in order to automatically grasp them.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.629-632
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• 1995

The formability of an automobile body panel is very important. So, we performed an annealing condition change for the development of annealing condition with temperature, atmospheric gas and the annealing cycle. Formability was changed under the influenced of the mechanical properties of steel sheet for the automobile body panel. Therefore, ot os important in the BAF(Batch annealing furnace) annealing process. Because mechanical properties were decided on the heat treatment method of the coil. So, we tested the development of mechanical properties according to the heat treatment method at the annealing furnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigations, we confirmed the following characteristics ; mechanical properties change under the influence of the annealing cycle and atmospheric gas.

• Natural Product Sciences
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• v.10 no.6
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• pp.325-329
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• 2004

The composition of essential oil from O. javanica was analyzed by gas chromatography-mass spectrometry. Using the broth dilution method and disk diffusion test, anti-microbial activities of the oil fraction and its main components were evaluated against various antibiotic-susceptible and resistant strains of pathogenic microorganisms. As a result of GC-MS analysis, 57 compounds, including ${\alpha}-terpinolene$ (28.1%), dl-limonene (16.0%), ${\gamma}-terpinene$ (10.3%), ${\beta}-pinene$ (9.7%) and ${\alpha}-pinene$ (6.0%) were identified in the essential oil fraction. The essential oil fraction of O. javanica and its main components exhibited significant inhibitory activities, particularly against Candida albicans (antibiotic-susceptible strains) and Streptococcus pneumoniae (antibiotic- susceptible and resistant strains). The main components of the O. javanica oil fraction displayed different patterns of activity against the three tested Candida species as exemplified by the differential minimum inhibiting concentration (MIC) values. The disk diffusion test showed that the activities were dose dependent.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.203-216
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• 2018

Product familiarity is vital to assess the purchase intention of consumers. In this study, a conceptual model was proposed to investigate the relationship among organic products familiarity, perceived value (measured by quality, emotional, price and social dimensions), and the purchase intention of students. The model was empirically tested using questionnaire survey data collected from 235 university students. The results reveal that organic products familiarity is positively associated with quality, emotional value, price value and social value. On the other hand, emotional value, price value and social value is also positively associated with purchase intention whereas quality shows insignificant relationship with purchase intention. Overall, the result shows students have positive outlook about their intention to purchase organic products.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.3
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• pp.199-205
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• 2011

This paper proposes a framework to predict the mechanical fault of hot rolling mill system (HRMS). The optimum process of HRMS is usually identified by the rotating velocity of working roll. Therefore, observing the velocity of working roll is relevant to early know the HRMS condition. In this paper, we propose the framework which consists of two methods namely spectrum matrix which related to case-based fast Fourier transform(FFT) analysis, and three dimensional condition monitoring based on novel visualization. Validation of the proposed method has been conducted using vibration data acquired from HRMS by accelerometer sensors. The acquired data was also tested by developed software referred as hot rolling mill facility analysis module. The result is plausible and promising, and the developed software will be enhanced to be capable in prediction of remaining useful life of HRMS.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.558-563
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• 2014

To reduce the transmission of large gun-generated noise from the firing test range to the community, we have tested a silencer to be used with howitzer(155mm KM114A2) after simulation. Numerical analysis was conducted by using a commercial CFD code, FLUENT. To analyze complex blast flow fields, the Spalart-Allmaras model was applied under 2 dimensional and axisymmetric conditions. Firing tests were also performed with the KM114A2 howitzer while the silencer was installed. This paper describes a result of comparison between results of computer analysis and test outcomes which were gotten by firing 155mm projectiles at the testing range. This paper will also be informative to the muffler design which will be adapted to 155mm large gun in the future.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.609-614
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• 2014

This study is on the experiment of the pipe noise due to the internal fluid. The straight pipe, the $90^{\circ}$ mitred pipe, rounded $90^{\circ}$ and $1350^{\circ}$ pipe were tested and measured the vibration and noise. In the experiment, the vibration and noise level of the straight pipe and rounded pipes show that the vibration and noise level are almost same. The $90^{\circ}$ mitred pipe shows the high vibration and noise level. In the prediction of noise due to the internal flow, the use of pipe surface vibration and radiation efficiency shows good agreement with experiment result.