• The Korean Journal of Mycology
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• v.36 no.1
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• pp.36-40
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• 2008

Studies were processed to confirm the differences of productivity according to sawdust size and effect of additives for sawdust cultivation of shiitake. In results of investigation until shiitake mycelia fully spread on surface of sawdust medium, mycelial growth in treatment of sawdust size $3{\sim}5\;mm$ with $CaCO_3$ and $KNO_3$, and treatment of sawdust sizw $3{\sim}5\;mm$ without $CaCO_3$ and $KNO_3$ was the fastest. And, in investigation of rate of weight reduction, treatment of sawdust size below 1 mm without $CaCO_3$ and $KNO_3$ was the highest. The tendency of fruiting was somewhat different according to treatments. In case of sawdust size below 1 mm with $CaCO_3$ and $KNO_3$, yield produced from 1st to 2nd flushing period was over 80%. However, in case of sawdust size below 1 mm plus $5{\sim}7\;mm$ without $CaCO_3$ and $KNO_3$, yield produced from 3rd to 4th flushing period was more than it from 1st to 2nd flushing period and rate of yield produced from 1st to 2nd flushing period to total yield was 34%. Results of investigation on productivity, yield and the number of fruit-bodies were remarkably different according to treatments. Sawdust size $3{\sim}5\;mm$ with $CaCO_3$ and $KNO_3$, whose total yield and the number of fruit-bodies were 568 g and 67, respectively, was the highest. And, total yield of medium of sawdust size below 1 mm plus $2{\sim}3\;mm$ without $CaCO_3$ and $KNO_3$ was lowest as 227 g and the number of fruit-bodies of medium of sawdust size below 1 mm plus $5{\sim}7\;mm$ without $CaCO_3$ and $KNO_3$ was lowest as 24. In investigation on amount of fruit-bodies over 10 g, medium of sawdust size $3{\sim}5\;mm$ with $CaCO_3$ and $KNO_3$ was highest as 397 g.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.597-608
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• 2005

The aim of this study is to determine whether full-mouth disinfection therapy(FMT) in our clinical setting would show better improvement of clinical parameters than partial mouth disinfection therapy(PMT) in chronic periodontitis and aggressive periodontitis patients. Among 12 patients, 6 were treated FMT and other 6 were treated PMT. Clinical parameters were calculated 3 months and 6 months after initial therapy. 1. There were no statistically significant differences between FMT and PMT in the reduction rate of bleeding on probing after 3 months, 6 months 2. Initial probing depth was 4-6mm, the mean probing depth after 3 months was 2.2mm vs 2.5mm(FMT vs PMT), after 6 months was 2.4mm vs 2.8mm. This was significantly lower in the FMT groups. 3. Initial probing depth was ${\geqq}$ 7mm, the reduction rate of mean probing depth during first 3 months was 4.8mm vs 4.1mm(FMT vs PMT), and 3 to 6 months was 0.5mm vs 0.3mm. This was significantly larger in the FMT groups. 4. Initial probing depth was 4-6mm, the mean clinical attachment level after 3 months was 2.3mm vs 2.7mm(FMT vs PMT), after 6 months was 2.7mm vs 3.0mm. This was significantly lower in the FMT groups. 5. Initial probing depth was ${\geqq}$ 7mm, the reduction rate of mean probing depth during first 3 months was 4.0mm vs 3.0mm(FMT vs PMT), and 3 to 6 months was 0mm vs -0.1mm. This was significantly larger in the FMT groups. Although the results provided us with succeccful clinical improvement in aggressive periodontitis, further research is needed to prove its additional benefit in the treatment of chronic periodontitis

• Journal of Fashion Business
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• v.24 no.3
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• pp.85-100
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• 2020

Recently, 3D printing technology, which is suitable for small-volume production of many varieties, has become considered a key manufacturing technology in the 4th industrial revolution. However, the nature of 3D printing technology means it is not yet able to be applied to traditional textiles due to Fabric Flexibility. The aim of this study is to investigate Textile Structural Design by finding the optimal yarn thickness for Selective Laser Sintering (SLS) 3D printed structures on geogrid dobby woven fabric that gives the optimal flexibility and tensile strength in the final product. The test results for tensile load strength of the 3D printed test samples, using 1.0mm, 0.8mm, 0.6mm and 0.4mm yarn thicknesses, showed that all were found to be above 250N, this higher than the tensile strength of 180N that is recommended for textile products. Based on these results, the four dobby structural patterns with 3D printing produced had four yarn thicknesses: 1.0mm, 0.8mm, 0.6mm, and 0.4mm. The thinner the yarn, the more flexible the fabric; as such the optimal conditions to produce SLS-based 3D printed textiles with suitable strength and flexibility used a thickness of yarn in the range of 0.4mm to 0.6mm.

• Fire Science and Engineering
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• v.29 no.3
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• pp.48-52
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• 2015

In this study, we have evaluated whether the mixing ratio is proper by creating a mixing device for foam proportioner that mainly is employed in practice utilizing a metering venturi type. In case of the mixing ratio for 3%, water under pressure of 76 mm in diameter and the original liquid of a foam fire extinguishing agent of 31.75 mm in diameter have showed up the fluctuation rate just as much as 3.1~3.5% of the mixing ratio. Because water under pressure of 101.6 mm in diameter and the original liquid of a foam fire extinguishing agent of 38.1 mm in diameter have showed up 3.3~3.7% of the fluctuation rate, water under pressure of 101.6 mm in diameter and the original liquid of a foam fire extinguishing agent of 38.1 mm in diameter have satisfied 3.0~3.9% of performance criterion. And also, in case of the 6% of mixture rate, water under pressure of 76.2 mm in diameter and the original liquid of a foam fire extinguishing agent of 31.75 mm in diameter have showed up the fluctuation rate just as much as 6.4~6.8% of the mixing ratio. Because water under pressure of 101.6 mm in diameter and the original liquid of a foam fire extinguishing agent of 38.1 mm in diameter have showed up 6.0~6.8% of the fluctuation rate, water under pressure of 101.6 mm in diameter and the original liquid of a foam fire extinguishing agent of 38.1 mm in diameter have satisfied 6.0~7.0% of performance criterion.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.185-189
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• 2006

Optimum tapping size and number for sap collection were investigated to minimize damage on tree growth and secure resources for sap by sap collection of Acer mono. The amounts of sap collected by tapping size of 12 mm, 10 mm and 8 mm was 189 L, 140 L and 193 L, respectively. Fusion rates by tapping size were 100% for 8 mm, 89% for 10 mm and 85% for 12 mm, respectively. Amount of sap by size and number of tapping were much at three, two and three tappings to small, middle and large diameter tree in case of 8 mm tapping, and it was large in quantity at two tappings of 12 mm tapping to large diameter tree, respectively. Trees tapped from one to three tappings of 8 mm size for small diameter tree with treatment of DB ointment (mixture of thiophane ointment and 2% bamboo charcoal powder) were completely filled up within 6 months. Diameter growth by number of tapping of 8 mm size was 0.60 mm for one tapping, 1.12 mm for two tappings and 0.47 mm for three tappings to small, middle and large diameter tree, respectively. In case of 12 mm tapping size, diameter growth was fast in the order of large (0.55 mm), middle (0.30 mm) and small (0.23 mm) diameter tree, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.129-137
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• 2001

The proptosis of 100 healthy Korean young people was estimated. The average protrusion measured with Hertel exophthalmometer was $14.6{\pm}0.51mm$ and $13.7{\pm}0.42mm$ in the right eye, $14.2{\pm}0.46mm$ and $13.6{\pm}0.42mm$ in the left eye by two observers(A, B), and so right eye was higher than left eye. There is no significant difference of proptosis between two eyes and among the visual acuity in the man and woman. The average coefficient of variation among five measurements by two observers was 3.53% and 3.10% in the right eye, 3.32% and 3.11% in the left eye. The mean base line by two observers was $106.7{\pm}1.13mm$ and $108.4{\pm}1.08mm$ in the man, $103.4{\pm}1.23mm$ and $104.8{\pm}1.02mm$ in the woman, respectively.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.78-78
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• 2001

본 연구는 초자화동결법(vitrification)을 이용하여 미성숙 소 난포란의 동결기술을 개발하기 위하여 시도하였으며 난포의 크기와 동결보호제의 농도 및 난황의 첨가가 동결-융해 후 미성숙 소 난포란의 생존성에 미치는 영향을 조사하였다. 미성숙 난자는 3mm 미만과 3mm 이상으로 구분된 난포로부터 채란하였으며 동결처리 전 동결보호제로서 30%EG과 40%EG, 그리고 각각에 10%의 egg yolk을 첨가하여 동결-융해 후 미성숙 난자의 생존성과 체외성숙율 및 체외수정율을 비교하였다. 생존율과 성숙율에 있어서 3m 미만과 3mm 이상의 2 처리구 모두 40%EG에 10%의 egg yolk을 첨가할 경우 유의적으로 높은 결과를 보였으나 3mm이하에서는 EG수준과 egg yolk 첨가 유무간에 생존율과 성숙율에 유의적인 차이가 나타나지 않았다. 동결-융해 후 체외수정율은 3mm 미만에서는 처리구간에 유의적인 차이를 보이지 않았으나 3mm이상의 경우에서는 40%EG에 10%의 egg yolk 첨가구가 다른 처리구에 비해 유의적으로 높았다. 난포의 크기에 따른 동결-융해 후 생존율은 3mm미만의 난포란이 3mm이상 보다 높았으나 성숙율과 수정율에 있어서는 3mm이상이 3mm미만의 난포란에서 보다 다소 높았다. 생존율, 성숙율 및 수정율 모두 난포크기간에 유의차는 인정되지 않았다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.122-129
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• 2012

This study investigates structural and vibration analyses according to the thickness of bicycle frame tube. The model of bicycle frame has the dimension as length of 862mm, width of 100mm and hight of 402.5mm. There are 3 kinds of models with tubes of top, down and seat at bicycle frame as thicknesses of 10, 15 and 20mm. The maximum displacement and stress occur at the center part of seat stay and at the installation part of rear wheel respectively. Maximum displacements become 0.031936, 0.029159 and 0.027984mm in cases of thicknesses of 10, 15 and 20mm respectively. In case of thickness of 20mm among 3 cases, maximum displacement becomes lowest. But maximum stresses become 10.019, 8.5492 and 9.2511MPa in cases of thicknesses of 10, 15 and 20mm respectively. In case of thickness of 15mm among 3 cases, maximum stress becomes lowest. There is no resonance at practical driving conditions and natural frequency remains almost unchanged along the change of thickness. In case of the displacement due to vibration mode, the displacement difference at thickness between 15mm and 20mm becomes 1/2 times than that between 10mm and 15mm. Design at bicycle frame tube becomes most economical and durable effectively in case of thickness of 15mm among 3 cases.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.12-19
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• 2000

In this paper, not only the development of optimizing of friction welding with more reliability and more applicability but also development of in-process real-time weld quality(such as strength and toughness) evaluation technique by acoustic emission for friction welding of the engine exhaustive valve(SUH3-SUH35 dissimilar steels of 12.3mm, 16mm, 20mm and 24mm in diameters) were performed, comparing with the other FRW matches of materials such as SUH3 to SUH31, SUH3 to STS303 and SUH3 to STS304. As an important result, the techniques for dissimilar friction welding optimization of engine heat resisting steels SUH3 and SUH35( 12.3mm, 16mm, 20mm, 24mm) and its real-time weld quality evaluation by AE were developed, considering on both diameter and carbon equivalent effects.

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.43-49
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• 2008

The evaporation heat transfer coefficient and pressure drop of R-22 and R-407C in horizontal copper tubes were investigated experimentally. The main components of therefrigerant loop are a receiver, a compressor, a mass flow meter, a condenser and a double pipe type evaporator (test section). The test section consists of a smooth copper tube of 4.3 mm and 6.4 mm inner diameter. The refrigerant mass fluxes were varied from 100 to $300[kg/m^2s]$ and the saturation temperature of evaporator were 5 [$^{\circ}C$]. The evaporation heat transfer coefficients of R-22 and R-407C rise with the increase in mass flux and vapor quality. The evaporation heat transfer coefficient of R-22 for inner diameter tube of 4.3 mm and 6.4 mm is about $7.3{\sim}47.1%$ and $5.68{\sim}46.6%$ higher than that of R-407C, respectively.