• Laser Solutions
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• v.6 no.3
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• pp.29-35
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• 2003

In semiconductor processing, there are two types of particle contaminated onto the wafer, i.e. dry and wet state particles. In order to evaluate the cleaning performance of laser shock wave cleaning method, the removal of 1 m sized alumina particle at different particle conditions from silicon wafer has been carried out by laser-induced shock waves. It was found that the removal efficiency by laser shock cleaning was strongly dependent on the particle condition, i.e. the removal efficiency of dry alumina particle from silicon wafer was around 97％ while the efficiencies of wet alumina particle in DI water and IPA are 35％ and 55％ respectively. From the analysis of adhesion forces between the particle and the silicon substrate, the adhesion force of the wet particle where capillary force is dominant is much larger than that of the dry particle where Van der Waals force is dominant. As a result, it is seen that the particle in wet condition is much more difficult to remove from silicon wafer than the particle in dry condition by using physical cleaning method such as laser shock cleaning.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.7 s.196
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• pp.106-111
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• 2007

In this paper, the transient brake time was studied on the van type vehicle with accelerometer. Experiments were carried out on the asphalt(new and polished), unpacked road(earth and gravel) and on wet or dry road conditions. The transient brake time is not effected bzy the vehicle speed. The transient brake time is about 0.41$\sim$0.43second on the asphalt road surface and the error range is within 0.1$\sim$0.16second. For the asphalt road condition, the transient brake time is not effected by both new asphalt road surface and the polished asphalt road surface. With compared by dry and wet road surface condition, the transient brake time of wet condition is longer than dry road condition and compared with unpacked road condition and packed road condition, unpacked road condition is shorter than packed road condition. It is considered that the transient brake time is effected by the road surface fraction coefficient. In other words, the transients brake time increases as friction coefficient decreases.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.73-81
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• 2006

A sensitivity analysis about effects of influencing factors on the stability of Soil cut slope was performed. Slope stability analyses were carried out under dry, rainy and seismic conditions. Dominant factors controlling the slope stability were chosen such as cohesion and internal friction angle, unit weight of soil, water table and seismic horizontal coefficient used for the slope stability during earthquake. Parametric stability analysis with those factors was performed for sensitivity analysis. As results of analyzing the sensitivity of factors under dry and rainy conditions, effects of cohesion, internal friction angle and unit weight of soil on the stability of slope are more critical in the dry condition than in the rainy condition. Cohesion and internal friction angle are more dominant factors influencing the slope stability irrespective of dry or rainy conditions than unit weight of soil and the horizontal seismic coefficient. The unit weight and the horizontal seismic coefficient affects crucially the stability according to conditions of slope formation and dry or rainy seasons. For the effect of horizontal seismic coefficient on stability of slope, safety factor of slope is not affected significantly by dry or rainy conditions. However, increase of the horizontal seismic coefficient under the rainy condition floes reduce the safety factor significantly rather than the dry condition. Therefore, it is needed that the location of the water table is assigned appropriately to satisfy the required safety factor of stability in the case of checking slope stability for the rainy and seismic conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.353-353
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• 2009

It is an important task to construct a recycling society with a low damage on the environment in our century. Magnetic separation is expected to be applied for the industrial waste treatment as an important supporting technology. In the magnetic separation of dry condition, the cohesive force between particles is strong compared with that in the wet condition's magnetic separation. The use of high magnetic field by the superconducting magnet enhances the powder's magnetic substance capture ability of the magnetic separation. In this study, the POSCO's coolant sludge of hot rolled steel was used for the superconducting magnetic separation of dry condition. Cryo-cooled NB-Ti superconducting magnet with 100 mm room temperature bore and 600 mm of height was used for magnetic separator.

• Proceedings of the Korean Society of Crop Science Conference
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• 2004.04a
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• pp.102-103
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• 2004

[ $\bigcirc$ ] In the growth simulation without changing of module with ORYZA2000, dry matter, LAI and leaf nitrogen content(FNLV) were estimated well under high nitrogen applicated condition, but overestimated under low nitrogen applicated condition. $\bigcirc$ Nitrogen stress factor on the SLA was introduced into ORYZA2000 because especially overestimated LAI under low nitrogen applicated condition was originated from SLA decrease with leaf nitrogen(FNLV) decrease. $\bigcirc$ In the growth simulation with modified SLA modified module, LAI was estimated well under even low nitrogen applicated condition, but dry matter was hardly changed compared with default. $\bigcirc$ Simulated plant nitrogen content and dry matter have no clear difference between modules, but compared with observed values, panicle weight(WSO) and rough rice yield(WRR14) were overestimated under high nitrogen applicated because of lodging, pest, disease and low nitrogen use efficiency.

• Journal of Korea Foundry Society
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• v.3 no.2
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• pp.92-99
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• 1983

This study has been carried out to investigate into the difference of rolling life and rolling wear characteristics for various gray cast iron under unlubricated dry rolling condition by amsler type wear test with 9.09% sliding.The results obtained from this study are summerized as follows: 1) It has been found that the amount of rolling wear id decreased when tensile strength and hardness are low, and then the rolling life up to generation of abnormal wear is conspicuously increased. 2) At the given condition the amount of rolling wear has been found to decrease as carbon equivalent of gray cast iron increases and resistance of crack propagation is an important factor on improvement of wear characteristics. 3) The amount of rolling wear is increased with increasing rolling revolution and wear of gray cast iron under dry rolling condition is characterized by three modes; initial wear, stationary wear and abnormal wear. 4) It has been found that the amount of rolling wear is increased with increasing maximum compressive stress and extremely increased when maximum compressive stress is over 59.1kg.f/mm.

• Korean Journal of Medicinal Crop Science
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• v.27 no.6
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• pp.390-396
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• 2019

Background: Usually ginseng seeds are sown during autumn and spring. Sowing in spring often results in poorer seedling establishment than in autumn. One of the reasons for poor germination could be cold-treatment condition for breakage of physiological dormancy during winter. Here we tested the effects of storage temperature used during cold treatment on germination. Methods and Results: Germination properties were observed after dehiscent seeds were stored as wet and dry at 2℃, -2℃, -3.5℃ and alternating temperature (AT). Seed dryness and storage temperature affected germination properties (p < 0.01). Wet and AT condition germinated highest, and wet and -3.5℃ condition germinated lowest, which was 91.2% and 1.4% respectively. Mean germination time (MGT) of the wet and AT condition was faster than other treatments at 2.4 days, and the dry and -2℃ condition was the longest. Germination performance index (GPI) was highest for wet and AT condition (37.7%) and the lowest for wet and -3.5℃ condition (0.5%). The growth of above-ground and below-ground were the best for wet and 2℃ condition, and wet seeds showed better growth than dry seeds (p < 0.01). Conclusions: For cold treatment, ginseng seeds may not be stored below -2℃ for successful germination during spring sowing.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.1
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• pp.39-55
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• 2022

This study carried out the laboratory tests for AE signal attenuation to determine the attenuation coefficient (α) of silo concrete in Gyeongju low and intermediate-level disposal environments. The concrete samples were prepared by satisfying the concrete mixing ratio used in the Gyeongju disposal silo, and these samples were additionally exposed depending on the temperature conditions and saturation and, dry condition. As a result of attenuation tests according to the transmission distance on three concrete specimens for each disposal condition, the AE amplitude and absolute energy measured on the saturated concrete were higher than that of the dry concrete in the initial range of the signal transmission distance, but the α of the saturated concrete was higher than that of the dry concrete. Regardless of the saturation and dry conditions, the α tended to decrease as the temperature increases. The α had a more major influence on the saturation and dry condition than the temperature condition, which means that the saturation and dry condition is the main consideration in measuring the signal attenuation of a concrete disposal structure. The α of concrete in the disposal environment expect to be used to predict the integrity of silos concrete in Gyeongju low and intermediate-level disposal environments by estimating the actual AE parameter values at the location of cracks and to determine the optimum location of sensors.

• International Journal of Naval Architecture and Ocean Engineering
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• v.1 no.2
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• pp.57-63
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• 2009

Numerical simulations have been carried out on the flooding system of a dry located at the south coasts of Iran. The main goals of seawater flow haracteristics in the intake channels conditions of the flooding system are imposed in the modeling. The upstream boundary condition is the tidal fluctuations of sea water level. At the downstream, the gradually rising water surface elevation in the dry described in a transient boundary condition. The numerical results are compared with available laboratory a good agreement is obtained. The seawater discharge through the flooding system and the required time to filling up the dry dock is determined at the worst case. The water current velocity and pressure on the rigid boundaries are discussed.

• Journal of Korean society of Dental Hygiene
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• v.12 no.2
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• pp.293-305
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• 2012

Objectives : The purpose of this study was to confirm effects of oral exercise program intended to improve the condition of salivary hypofunction and to provide basic data for development of oral health program for the elderly Methods : The subjects were 125 elderly women who resided in Gyeong-In area and were aged 65 years and older. During a 2-month period, an oral exercise was conducted twice a week. A survey was conducted by interviewing the selected elders to determine the state of their subjective dry mouth. Unstimulated whole saliva was measured before and after the oral exercise program. Results : There was a significant improvement in subjective dry mouth symptoms, severity scores of dry mouth after the oral exercise, and there were affected by age and income level. There was a significant increase in unstimulated whole-saliva after the oral exercise program. There was positive interrelationship between dry mouth Symptom improvement level and inconvenience improvement level, and between inconvenience improvement level and the increase of unstimulated whole-saliva. Conclusions : This study showed the effects of the oral exercise program. It is suggested that this oral exercise program has positive effects on the condition of dry mouth. For the explicit improvement effect on the condition of dry mouth, the oral exercise program needs to be carried out in consideration of the elderly's general characteristics.