• 설비공학논문집
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• 제7권2호
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• pp.207-216
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• 1995

Flow and heat transfer characteristics of mixed convection heat transfer in a rectangular en-closure with various outlets are numerically investigated. The parameters considered here include Reynolds number, Grashof number and the position of outlet. The results show streamlines, isotherms, Nusselt numbers, velocity and temperature distributions. It has been shown that as Reynolds number increases, the size of cell decreases at Re$\leq$100 and increases at Re>100 for $Gr=10^4$. There is a minimum size of cells at Re=100, $Gr=10^4$. The maximum mean Nusselt number occurs at Re=400, $Gr=10^4$ and one right outlet. The mean Nusselt numbers can be formulated by the correlation equation $Nu=C{\cdot}Gr^a{\cdot}Re^b$.

• 통상정보연구
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• 제3권2호
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• pp.261-280
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• 2001

From the IMF(International Monetary fund) crisis, the management conditions of the trading company which run business in world market, has rapidly changed. In particular, the trading conglomerate's competitive power have declined. This study, addressing such changes, intend to analyze what factors are that have generated this changes in trading conglomerate's environment. The study specifically takes it into account that the differences between Korea trading company and Japan's. This research was confirmed by data and field survey in two country. The results of research are summarized as follow. The Korean trading company are inferior to the Japanese trading company in total volume(Korea: 24.1, Japan 100), the benefit volume(Korea: 8.7, Japan 100), the stability of turnover(Korea: 36.6, Japan 100), the network power in foreign country(Korea: 19.2, Japan 100), the power of e-business(Korea: 17.0, Japan 100). But the debt ratio of Korea company is significantly lower than that of Japan's(Korea: 160.4%, Japan 940.5%). In conclusion, providing that the Korean trading company want to be a world-class champion in trading field, they have to introduce the new management strategies which means the high-profit base trading, the long term investment and the internet business.

• 한국재료학회지
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• 제7권6호
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• pp.522-528
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• 1997

RF-magnetron Sputtering Process를 이용하여 Pt/Ti/Si(100)기판위에 lanthanum-modified lead titanate 박막을 제작하였다. 기판온도와 증착시간이 증가함에 따라 증착율은 감소하였다. 기판온도가 증가함에 따라 fine grain들은 large grain으로 변화하였다. Perovskite구조는 기판온도 54$0^{\circ}C$, gas pressure 30mtorr에서 나타나기 시작하였다. 본 실험에서 perovskite 박막제작에 대한 조건은 기판온도 58$0^{\circ}C$, gas pressure 30mtorr였다. Pt/Ti/Si(100) 우선 배향된 박막을 얻었다. La양이 증가함에 따라 유전율, 항전계, 잔류분극량은 증가하였다. 중심주파수가 44.7MHz, 전파속도는 2680m/sec를 가지는 SAW filter 특성을 얻었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.52-52
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• 2019

Buckwheat is well-known crop for containing a high contents of flavonoids that are effective in vascular disease. The current study was performed to estimate the influence of morphological characterization of Fagopyrum esculentum (ES) germplasm for seed's two major flavonoids contents: rutin and quercetin. We found that the red stem color, pale green leaf color, arrowhead leaf shape, white flower color, pale brown seed coat color, and egg-shaped seed were significantly associated with 77%, 56.7%, 83.7%, 98.7%, 70.8% and 74.5% germplasm, respectively. Overall, the rutin contents of ES germplasm ranged from 0.30 to 47.86 mg/100g dry weight (DW) and the quercetin contents ranged from 0 to 1.22 mg/100g DW. The rutin contents of germplasm possessing red stem color, pale green leaf color, arrowhead leaves, white flower color, pale brown seed coat color and egg-shaped seed ranged from 7.22 to 47.86 mg/100g DW. However, the quercetin contents of germplasm with red stem color and pale brown seed coat color ranged from 0 to 1.15 mg/100g DW, with pale green leaves ranged from 0 to 0.96 mg/100g, with arrowhead leaves and white flower ranged from 0 to 1.22 mg/100g and with egg-shaped seed ranged from 0.32 to 1.22 mg/100g DW. In PCA analysis, the first three principal components (PCs) showed Eigen value more than 1 and accounted for 51.70% of variation. For both higher contents of rutin and quercetin, the morphological evaluation in ES shows a tendency of red stem color, arrowhead leaves, pale green leaf color, white flower color, pale brown seed coat color and egg-shaped seed. From this information, we can assume the rutin and quercetin contents by the morphological characteristics of the germplasm. And It could be useful in improving the rutin and quercetin contents and selecting proper resources for cultivation in existing buckwheat cultivars.

• 한국식품영양학회지
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• 제14권2호
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• pp.161-166
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• 2001

맥주효모박 중의 단백질 함량은 41.7%, 탄수화물은 46.0%이었다. 주요 무기질은 K. P, Mg, Ca이었으며, 이들의 함량은 각각 1659.7mg%, 1,197.4mg%, 210.4mg% 및 105.6mg% 이었다. 맥주효모박 중의 주요 비타민은 비타민 C와 비타민 B군이었으며 이들의 함량은 각각 7.9IU/100g 및 4.2IU/100g이었다. 맥주효모박의 자가소화 최적반응농도는 10% 였으며, 자기소화 촉진 및 오염방지제로 사용된 에탄올과 NaCl의 최적 농도는 맥주효모 현탁액의 경우 NaCl 3% 첨가구에서, 빵효모현탁액의 경우 NaCl 5% 첨가구에서 가장 효과적이었다. NaCl의 첨가에 의한 자가촉진효과는 맥주효모박보다 빵효모에서 더 우수하였다. 또한 맥주 효모현탁액에 에탄올을 첨가한 경우, 에탄올 첨가 농도에 따른 자가소화 촉진효과의 차이는 나타나지 않았으며, 빵효모 현탁액에 에탄올을 첨가한 경우 에탄올 3% 첨가구에서 가장 효과적이었다. 이들의 결과로 볼 때 에탄올의 첨가에 의한 자가소화 촉진효과 또한 맥주효모박에 비해 빵효모가 더 우수하였다. 맥주 효모박을 자가소화시킨 후 glucanase의 첨가는 정미성이 강한 IMP와 GMP의 함량을 160% 정도 증가시켰다.

• Journal of the Korean Wood Science and Technology
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• 제1권2호
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• pp.3-10
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• 1973

This study was carried out to examine the characeristics of waste sanders(S)from. plywood and pre-finishing plywood surface sanding and double saw finishing, as a new extander in urea-formaldehyde resin(UFR) in plywood adhesive, and to focus, adhesive strength using the glue extended with milled sanders(MS) as extender, leveling the optimum amount of MS to be added, and examining the physical properties of glue extended MS & S. Also economical good feasibility of substitution for wheat flour(WF) with MS as a new extender is analyzed and presented in details. Selecting three standard samples of 80, 100 and 180 mesh, sorking them in distilled water at $20^{\circ}C$, 24 hours, redrying at $105^{\circ}C$ and rescreening the sample with standard screen, again, the 3 samples of 80, 100, and 180 mesh are passed 23 percent through 80 mesh sander standard sample 27 percent through on 100 mesh and only 10.9 percent through 180 mesh, respectively. The particle size of retained parts are greater in size of redried form. It seems undoubtly that particles to be extended in glue are got swollen and become greater in size and coarser in shape. The shape of fresh S particles are irregular thin needle with small scale, as shown in Figure 5. PFS are so finer than plywood S that only 9.8 percent of the S retained on 100 mest screen, 24. 30 percent on 100-160 mesh, and 65.9% on 160-180 mesh. But particle size of the fresh S is large enough to make the viscosity of glue direct extended with S too high to apply it glue spreader. The glue extended with milled sanders(MS). 3 hours milled PFS or 6 hours milled plywood S, having particle sizes shown in Tables 7 and 8, as ratio of Reain/MS/WF/water: 100/8/8/10, indicate good viscosity of 16 to 24 ps, as shown in Figure 5, for applying direct to glue spreader, have high tensile-shear strength (adhesive strength), 102.4 kp/$cm^2$, and 94 percent wood failure.

• 한국구조물진단유지관리공학회 논문집
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• 제22권3호
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• pp.31-37
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• 2018

이 논문은 압축강도 수준(100, 140, 180 MPa급)에 따른 HPFRCC의 동적충격 인장강도를 평가하였다. 먼저 100, 140, 180 MPa급 HPFRCC의 압축응력-변형률 관계를 분석한 결과 압축강도는 각각 112, 150, 202 MPa로 나타났으며, 압축강도가 높아짐에 따라 탄성계수도 증가하는 경향을 나타내었다. 100, 140, 180 MPa급 HPFRCC의 정적 인장강도는 각각 10.7, 11.5, 16.5 MPa로 나타났으며, 압축강도가 높아질수록 인장강도도 증가하는 경향을 나타내었다. 반면 100 및 140 MPa급 HPFRCC에서의 인장강도 및 에너지 흡수능력은 압축강도 수준에 따라 큰 차이를 보이지 않았다. 이는 시험체의 규격 및 강섬유의 배열에 영향을 받은 것으로 판단된다. HPFRCC의 동적충격 인장강도를 평가한 결과, 변형률 속도가 10-1/s에서 150/s로 증가할수록 모든 HPFRCC의 인장강도와 동적증가계수는 증가하는 경향을 보였다. 한편 동일한 범위의 변형률 속도에서 HPFRCC의 압축강도가 낮을수록 인장강도에 대한 DIF가 높게 측정되어 효율적인 측면에서는 100 MPa급 HPFRCC가 가장 우수한 것으로 나타났다. 따라서 높은 수준의 인장성능이 요구되는 경우 높은 압축강도를 가지는 HPFRCC를 사용하는 것이 유리하며, 폭발과 같은 고속변형률 속도에서 보다 효율적인 접근을 위해서는 목표 압축강도에 근접한 HPFRCC를 사용하는 것이 바람직한 것으로 판단된다.

• 한국유기농업학회지
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• 제19권spc호
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• pp.63-66
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• 2011

An Intergenerational Horticultural Program in a rural community in Korea was tried out to enhance social interaction between elderly citizens and children, to promote the positive self-esteem of the elderly in a rural community, to change the attitude of children towards the elderly, and to create a rural community full of vitality. The clients were 20 elderly (60-80 years old) and 40 preschool children (6-7 years old). The activities in this program included seed of hope, round autumn garden, dish garden, in the vegetable patch, flower decoration for the Chuseok Festival, rainbow flower basket, heart card, fragrance of love, and a kimchi party. The results were a decrease in depression among the elderly from 44.0% to 33.7%. General satisfaction among the elderly was 100%. The desire to rejoin among the elderly was 100%. General satisfaction among the children was 100%. The desire to rejoin among the children was 93.5%.

• Journal of Advanced Marine Engineering and Technology
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• 제24권1호
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• pp.67-74
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• 2000

Recently, PTFE-polymide composites are being used self-lubricating parts for industrial field. Thus, this study is mainly concerned with friction and wear properties for the piston ring of non-lubricating air compressor which made of PTFE-polymide composites. The friction and wear test was carried out for the different composition ratio under the atomsphere room temperature and constant load of 7.69N and their friction and wear properties were compared with each other at various sliding speed. notable results are summarized as follows. PTFE 100% showed that friction coefficient was almost same values at 0.94 and 1.88m/s but the value was decreased at 2.83m/s because the friction temperature is higher than low speed. PTFE 80%-PI 20% showed the lowest mean friction coefficient at 2.83m/s. PTFE 20-PI 80% showed the highest friction coefficient at 0.94m/s and the value was decreased at high speed but the value is higher than other materials except PTFE 100 %. PI 100% showed the highest friction coefficient at 0.94 and 1.88m/s becuase adhesive wear mainly occurred that speed. PTFE 100% showed highest specific wear rate on the whole. Specific wear rate of PTFE 80%-PI 20% was almost the same value with PTFE 20%-PI80%. PI 100%showed the lowest value at high sliding speed because the friction surface was thicken and carbonated by high friction temperature.

• 생명과학회지
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• 제30권7호
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• pp.592-597
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• 2020

성숙 콩[Glycine max (L.) Merr.] 종자는 약 40%의 단백질을 함유하고 있으며 아이소플라본, 사포닌, 루테인, 비타민등 다양한 기능성 성분을 함유하고 있다. 그러나, Kunitz Trypsin Inhibitor (KTI) 단백질, 렉틴 단백질, 7S α' 서버유닛 단백질이 함유되어져 있어 콩의 품질과 기능성을 저하시키고 있다. 본 연구는 콩 및 콩 제품의 품질과 기능성을 저하시키는 KTI, 렉틴 및 7S α' 서버유닛 3가지 단백질이 모두 유전적으로 결핍된 콩 계통(titilelecgy1cgy1 유전자형)을 선발하기 위하여 진행되었다. 3개의 모본(개척2호, PI506876, Le-16)을 이용한 유전집단으로부터 성숙 종자에서 KTI, 렉틴 및 7S α' 서버유닛 3가지 단백질이 모두 없는 titilelecgy1cgy1 유전자형을 가진 1개의 계통을 개발하였다. 개발된 계통은 자주색 꽃, 유한신육형, 노란종피을 가지고 있으며 초장은 58 cm로 대원콩(46 cm)보다 길었다. 백립중은 27.1 g으로 대원콩(29.0 g)보다 작았다. 본 연구를 통하여 선발된 계통은 KTI, 렉틴 및 7S α' 서버유닛 3가지 단백질이 모두 없는 고품질 기능성 콩 품종 육성을 위한 중간모본으로 이용될 수 있을 것으로 사료되었다.