• 한국환경과학회지
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• 제23권7호
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• pp.1299-1305
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• 2014

For evaluating the effect of various artificial planting soil properties on the Euonymus fortunei 'Emelad'n Gold' growth, a container green wall system experiment was conducted in a wall of greenhouse at Konkuk University, Glocal campus. The experimental artificial planting grounds were prepared with different organic soil conditioner ratios (Control, $A_4O_1$, $A_2O_1$ and $A_1O_1$) and with drought tolerance and an ornamental value Euonymus fortunei 'Emelad'n Gold' was planted. The soil and plant characteristics were investigated from April to Jun 2010. The volumetric soil moisture contents were significantly increasing order as the amount of organic soil conditioner level increased in order to $A_1O_1$ > $A_2O_1$ > $A_4O_1$ > Control. At 4 treatment, soil chemical properties were inversely related to organic soil container ratios increase. The differences of root collar caliper, number of branch, and survival rate between the organic soil conditioner ratio were not significantly affected by organic soil conditioner. But, plant height, internode length, leaf length and leaf width were significantly shorter on plants planted $A_1O_1$ than plants planted other treatments. Therefore, Euonymus fortunei 'Emelad'n Gold' had good growth response regardless of organic soil conditioner ratio and the plant is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in artificial planting soil.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3017-3029
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• 2023

In the late in-vessel phase of a nuclear reactor severe accident, the internal heat transfer and crust evolution during the debris bed melting process have important effects on the thermal load distribution along the vessel wall, and further affect the reactor pressure vessel (RPV) failure mode and the state of melt during leakage. This study coupled the phase change model and large eddy simulation to investigate the variations of the temperature, melt liquid fraction, crust and heat flux distributions during the debris bed melting process in the hypothetical severe accident of HPR1000. The results indicated that the heat flow towards the vessel wall and upper surface were similar at the beginning stage of debris melting, but the upward heat flow increased significantly as the development of the molten pool. The maximum heat flux towards the vessel wall reached 0.4 MW/m². The thickness of lower crust decreased as the debris melting. It was much thicker at the bottom region with the azimuthal angle below 20° and decreased rapidly at the azimuthal angle around 20-50°. The maximum and minimum thicknesses were 2 and 90 mm, respectively. By contrast, the distribution of upper crust was uniform and reached stable state much earlier than the lower crust, with the thickness of about 10 mm. Moreover, the sensitivity analysis of initial condition indicated that as the decrease of time interval from reactor scram to debris bed dried-out, the maximum debris temperature and melt fraction became larger, the lower crust thickness became thinner, but the upper crust had no significant change. The sensitivity analysis of in-vessel retention (IVR) strategies indicated that the passive and active external reactor vessel cooling (ERVC) had little effect on the internal heat transfer and crust evolution. In the case not considering the internal reactor vessel cooling (IRVC), the upper crust was not obvious.

• Journal of Oral Medicine and Pain
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• 제32권3호
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• pp.283-292
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• 2007

구강장치를 이용한 코골이와 수면무호흡증의 치료는 하악이나 혀를 전방으로 이동시켜 기도공간을 확보하는데, 하악전방이동장치(mandibular advancement appliance, MAA)와 혀견인장치(tongue retaining device, TRD)가 주로 이용된다. 이 중 혀견인장치는 전치의 순측에 위치되는 혀 유지구(tongue bulb) 속에 생기는 음압을 이용하여 혀가 뒤로 밀리지 않도록 하는 구강장치로서 단독 혹은 하악전방이동장치와 복합된 형태로 사용하여 코골이와 수면무호흡증의 치료에 효과를 보이는 것으로 보고되고 있다. 본 연구는 혀견인장치의 제작을 용이하게 하고 표준화하기 위해 개개인에 적합한 혀 유지구의 크기를 조사하여 분류하고 혀 유지구의 크기와 유지력의 관계 및 신체적 변수와의 관계를 조사해 보고자 하였다. 환자를 대상으로 하기에 앞서, 정상인 젊은 남성을 대상으로 시행하였다. 실험을 위해 투명 아크릴 레진 판을 이용하여 폭(27-36 mm)과 두께(8, 10 mm)를 달리한 20 가지 크기의 혀유지구를 제작하고 준비하였다. 코골이와 수면무호흡증이 없는 36명의 젊은 남성 지원자들(평균연령: $24.47{\pm}2.58$세)을 대상으로 다양한 크기의 혀 유지구를 장착하여 유지력을 측정하여 최대유지력을 보이는 혀 유지구를 그 환자에게 적합한 크기의 유지구로 결정하고 측정한 값들을 기록하였다. 측정은 앉은 자세와 누운 자세에서 각각 시행하였다. 실험 결과, 앉은 자세와 누운 자세 모두에서 혀 유지구 크기에 따라 분류한 네 군의 유지력 사이에는 통계적으로 유의한 차이가 있었다 (p<0.05). 즉, 피검자에게 가장 적합한 크기의 유지구로 조사한 결과 유지구의 크기가 증가할수록 유지력이 증가하는 양상을 보였다. 신체적 변수와 혀 유지구 크기 사이의 관련성은 뚜렷하게 관찰되지 않았으며, 측정 자세에 따른 유지력 간에도 유의한 차이는 없었다. 본 연구의 결과는 혀 유지구의 유지력은 유지구의 크기, 즉 혀의 부피와 관련이 있음을 보여준다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.83-84
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• 2006

For phase transition method, good recording sensitivity, low heat radiation, fast crystallization and hi-resolution are essential. Also, A retention time is very important part for phase transition. In our presentation wall, we chose Ge-Se-Te material to use a Se material which has good optical sensitivity than Sb. A Ge-Se-Te sample was fabricated and Irradiated with He-Ne laser and DPSS laser to investigate a reversible phase change by light.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.819-824
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• 2010

Model test was performed for new earth retention system that is a kind of truss tower with non-supported excavation. For the model test, a dimensional analysis of the full-scaled truss tower system was performed. The horizontal displacement of the wall, bending stress acting on TTS system were measured during construction simulation. From the measurements, the performance of the truss tower system was investigated.

• 대한치과교정학회지
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• 제45권5호
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• pp.268-272
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• 2015

Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inherent limitations associated with thermoplastic polymer materials such as dimensional instability, low strength, and poor wear resistance. To solve these problems, we developed a new type of clear orthodontic retainer that incorporates multi-layer hybrid materials. It consists of three layers; an outer polyethylenterephthalate glycol modified (PETG) hard-type polymer, a middle thermoplastic polyurethane (TPU) soft-type polymer, and an inner reinforced resin core. The resin core improves wear resistance and mechanical strength, which prevent unwanted distortion of the bucco-palatal wall of the retainer. The TPU layer absorbs impact and the PETG layer has good formability, optical qualities, fatigue resistance, and dimensional stability, which contributes to increased support from the mandibular dentition, and helps maintain the archform. This new type of vacuum-formed retainer showed improved mechanical strength and rate of water absorption.

• 한국유가공학회:학술대회논문집
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• 한국유가공기술과학회 2005년도 창립 30주년 기념 국제심포지움 - 웰빙시대의 우유.유제품의 새로운 발견
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• pp.37-61
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• 2005

미세캡슐 (microencapsulation)은 내부 물질(core material)의 방출을 제어하기 위하여 여러 천연 및 생분해성 물질이 사용된다. 유청단백질은 이러한 목적에 아주 적합한 것으로 여겨지고 있는데 이는 독특한 이화학적 특성에 기인되는 것이다. 본 연구팀은 drug이나 생리활성물질을 피복하기 위하여 cross-linking 물질로 glutaraldehyde를 사용하여 수용성 이면서 유청단백질을 근간으로 하는 미세캡슐 제조기술을 개발하였다. 또한 생리적 조건에서 이들 캡슐의 분해 및 포집물질의 방출에 대한 연구를 수행하였는데 수용성 drug으로 사용된 theophylline은 유청단백질에 잘 분산되는 것으로 확인되었다. 이 분산액은 !%의 생리활성물질인 polyurethane을 함유하는 dichloromethane과 hexane 혼합불에 잘 확산이 되었다. 미세캡슐공정에서 피복물질로 사용되는 여러 물질중에서 유청단백질은 생리적 효능이 뛰어나고 여러 물리적 작용이 있기 때문에 새로운 피복소재로써 그 효용성이 매우 높다. 지금까지의 연구결과 유청단백질을 이용한 미세캡슐의 제조는 유청단백질이 가지는 기능적 효과와 내부물질이 지니는 약리효과를 동시에 이용할 수 있다는 점에서 향후 고부가 식품 의약품 첨가물질로써 유용성이 기대된다고 하겠다.

• 대한후두음성언어의학회지
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• 제27권1호
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• pp.30-34
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• 2016

Background and Objectives : Microsurgical resection of intracordal cysts is technically difficult and challenging because the wall of cysts may be tightly attached to underlying vocal ligament and/or overlying epithelium, and therefore their thin wall will easily rupture during surgical dissection. We aimed to evaluate the voice outcomes of standard microflap subepithelial resection and the recurrence rate depending on the intraoperative rupturing of the cyst. Materials and Methods : Medical records of Samsung Medical Center, Seoul, Korea, were reviewed for sixty-four consecutive patients who received surgical resection of vocal cyst using microflap subepithelial dissection technique between the year 2004 and 2013. Meticulous dissection was performed to completely remove the cyst wall while preserving the mucosa and the lamina propria as much as possible. Voice outcomes and recurrence rates were compared according to the type, size and the intraoperative rupture of cyst. Results : Presence or absence of cyst rupture was clearly described in the operation records of 41 patients. Intraoperative rupture of the cyst occurred in 32 of 41 (78%) patients. The recurrence was detected in 5 of 64 (7.8%) total cases and 4 of 32 (12.5%) cases of ruptured cyst, but not in 9 cases of intact extirpation. Rupture was more common in case of mucous retention cyst compared with epidermoid cyst (p=0.036). Subjective and objective voice parameters were measured at before and 3 months after surgery, which improved regardless of the cyst rupture. Conclusion : Although complete microsurgical extirpation of intracordal cyst while keeping the cyst wall intact is technically difficult, meticulous dissection with maximal preservation of surrounding tissue may warrant the improvement of voice outcomes.

• 한국식품과학회지
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• 제32권1호
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• pp.132-139
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• 2000

본 연구는 분무건조를 이용한 미세캡슐화 기술을 이용하여 유화압력 및 분무건조에 있어서 송풍 온도와 분무 속도를 최적화하는데 목표를 갖고 수행되었다. 분석지표로 유화액의 유화안정성과 flavor release를, 분무건조 분말의 total oil, surface oil, flavor release, 흡습성을 측정하고, SEM에 의해 분말의 형태를 관찰하였다. Wall system을 이용하여 piston-type homogenizer의 압력을 달리하여 실험한 결과 향기성분의 미세캡슐화를 위한 최적 유화압력은 20.7MPa이었다. 분무건조공정에 있어서 송풍 온도와 분무 속도를 독립변수로, total oil retention, surface oil content, flavor release를 종속변수로 반응 표면 분석법을 행한 결과 송풍 온도는 $170{\circ}C$, 분무 속도는 15,000rpm이 우수한 공정 조건임을 예측 할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1580-1587
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• 2006

Several researchers have demonstrated that the rumen microbial community rapidly adapts to saponins and proposed interval feeding to prevent this rapid adaptation. An in vivo experiment was carried out to examine the effect of daily versus application every third day (interval feeding) of Sapindus rarak saponins (SE) on rumen fermentation end products, protozoal counts and nutrient digestibility. Thirty sheep were allocated into 5 groups. Sheep were fed daily or every third day with two levels of SE (0.48 and 0.72 g/kg body mass). One group received no saponin and served as control. All sheep received the same diet, a mixture of elephant grass and wheat pollard (65:35 w/w). Independent of the feeding regime and the level of inclusion, the addition of SE decreased protozoal counts and rumen ammonia concentrations (p<0.01). Microbial N supply and N retention were not affected by the high feeding regime. Daily feeding negatively influenced rumen xylanase and cellulase activity, but only when the high level of saponins was fed. However, these negative effects on rumen cell wall degradation were not reflected in decreasing total tract digestibility of the organic matter or the plant cell walls. Our results show that rumen microorganisms do not rapidly adapt to S. rarak saponins.