• 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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.813-819
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• 2006

Skid Resistance is a index to represent the friction between tire and road surface, which influences driving safety. Skid resistance varies with the conditions of tire, abrasion of road surface, vehicle speed, drying, wet and freezing condition of road surfaces. Especially, freezing occurs when temperature drops below $0^{\circ}C$ followed by snow or rain causes decrease of skid resistance. To recover the decreased skid resistance deicing work is applied. As a results of deicing works, freezing condition is changed into wet condition. However the wet road surfaces containing the remaining deicings agents may not show the skid resistance of normal wet condition. In this study, skid resistances in the condition of freezing, deicing process and deicing agents remained after snow-removal are evaluated. The test results, skid resistance recover quickly when Pre-wetted salt spreading and NaCl was used as deicing method. Skid resistance of Deicing agents remained on the road surface showed that concrete is higher than asphalt. superior effect. Recovery rate of skid resistance by comparison wet condition is 54~80%.

• Journal of Ocean Engineering and Technology
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• v.1 no.2
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• pp.67-73
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• 1987

The feasibility for a practical use of underwater wet arc welding process is experimentally investigated by using low hydrogen and high oxide type electrodes and TMCP steel plates. Main results are summarized as follows: 1)The absorption speed of the coated low hydrogen and high titanium oxide type eletrodes becomes constant after about 30 minutes in water, and more steeping time in water does not influnce welding arc behavior. 2) By bead appearance and X-ray inspection, the high titanium oxide type electrode is better than the low hydrogen type in underwater arc welding process. 3) The mechanical properties of underwater wet arc welds depend upon welding conditions more than those of in-air welds, and the optimum welding condition can be obtained. 4) Because of quenching effect by rapid cooling rate in underwater wet welding, the maximum hardness of HAZ is increased relatively higher in underwater wet welding, process.

• Journal of Life Science
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• v.9 no.4
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• pp.368-374
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• 1999

Three soybean cultivars, Hwangkeum, Tanyeob and Enrei were planted in the same pot under glasshouse conditions to investigate the influence of the different soil water content such as pF 1.4(wet), 2.1(control) and 3.6(dry) on the transpiration rate, dry matter production and water requirement. The transpiration rate remained the high constant rates under the wet soil condition and the control than the dry condition, and showed a linear correlation between transpiration rate and solar radiation under the all condition of soil water. The transpiration rate highly increased in the morning, but dramatically decreased in the other time in a day. The dry matter production was higher under the conditions of wet soil and the control than that under the dry condition. Also, the dry matter production Tanyeob was higher than other cultivars under all soil water content. The water requirement was higher for Enrei and lower Tanyeob than the control.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.752-756
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• 2013

This study was carried out to investigate the effect of cooking condition on the water-soluble flavor precursors relevant to postmortem glycogen metabolisms in various beef muscles from Hanwoo (Korean cattle). The loins, striploins, top rounds, and eye of rounds from 40-mon-old heifers were cooked in either with $100^{\circ}C$ water bath (wet-cooking) or $180^{\circ}C$ household electric oven (dry-cooking) until attained to about $80^{\circ}C$ of internal temperature before the measurements of amounts of macroglycogen, proglycogen, free glucose, and lactate. The macroglycogen and proglycogen contents were not significant differences in all beef muscles between the wet-cooking and dry-cooking treatments. Regardless of cooking condition, the both loin and top round had higher (p<0.05) two types of glycogen than the eye of round. The free glucose and lactate contents presented higher trends in the dry-cooking treatment compared with the wet-cooking treatment. The wet-cooked top round had higher (p<0.05) free glucose than the wet-cooked eye of round. Moreover, the top round contained the highest lactate content regardless of cooking condition. Consequently, it is considered that the dry-cooking treatment would be more beneficial to the flavor of cooked beef muscles than the wet-cooking treatment.

• The korean journal of orthodontics
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• v.23 no.4 s.43
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• pp.671-691
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• 1993

To estimate the possibility in the application of TiN ion-plating to the orthodontic appliance, this study investigated frictional force and frictional coefficient between non-ionplated and TiN ion-plated to the orthodontic appliance. The obtained results were as follows : 1. For each group, the frictional force between metal bracket and arch wire in the wet condition was exhibited lower than that in the dry condition. 2. In the dry condition, the frictional force was lowest with fourth group, and it increased in the order of the 3rd, 1st, and 2nd group. Same situation happened in the wet condition. 3. Experimental results using ceramic & plastic bracket showed that group B was lower than group A, and group D was similar to group C. 4. The surface texture after experiment showed that the scratch due to a friction with bracket was observed in an arch wire of dry contition. Also the surface of bracket was rougher than before. 5. We observed that a specimen surface processed with the TiN ion plating was smoother than that of without the TiN ion plating. 6. The surface texture of a metal bracket and an arch wire in the wet condition was observed smoother than that in the dry condition. 7. In the dry condition, the friction coefficient of each specimen was very similar to each other, but in the wet condition, the friction coefficient of specimen processed with the TiN ion plating showed lower values.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.330-335
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• 1998

This research was conducted to evaluate the adhesion in tension of the polymer mortars for cement concrete repair. Various polymer types, binder ratios, and wet/dry conditions of the surface were considered in this study. Styrene-butadiene rubber (SBR) and ethylen vinyl acetate (EVA) used for polymer cement mortars. Epoxy resin (EP), and unsaturated polyester resin (UP) were used for polymer mertars. Adhesion in tension for the dry condition of the substrate surface was higher than that for the wet condition of the substrate surface under the same binder ratio. Therefore, in repairing concrete, the dry surface condition was effective on adhesion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.88-89
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• 2009

In this paper, we investigated about wet cleaning effect as deep trench formation methods for Power chip devices. Deep trench structure was classified by two methods, PSU (Poly Stick Up) and Non-PSU structure. In this paper, we could remove residue defect during wet. cleaning after deep trench etch process for non-PSU structure device as to change wet cleaning process condition. V-SEM result showed void image at the trench bottom site due to residue defect and residue component was oxide by EDS analysis. In order to find the reason of happening residue defect, we experimented about various process conditions. So, defect source was that oxide film was re-deposited at trench bottom by changed to hydrophobic property at substrate during hard mask removal process. Therefore, in order to removal residue defect, we added in-situ SCI during hard mask removal process, and defect was removed perfectly. And WLR (Wafer Level Reliability) test result was no difference between normal and optimized process condition.

• Journal of Welding and Joining
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• v.5 no.4
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• pp.28-35
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• 1987

The feasibility of underwater wet arc welding process is experimentally investigated by using high titanium oxide type electrodes and TMCP steel plates as base metal. It is assertained the tis process may be put to practical use. Main results are summarized as follows; (1) Sound underwater weld can be obtained by skilled welding operator, if proper welding conditions are selected. (2) In underwater wet arc welding process, the mechanical properties of HAZ are depend upon welding condition and the optimum welding condition can obtained. (3) The maximum hardness in the HAZ of TMCP steel plates is increased significantly in this welding process.