• 유공압시스템학회:학술대회논문집
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• 유공압시스템학회 2010년도 춘계학술대회
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• pp.126-131
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• 2010

In order to improve the life and reliability of fluid components used in the Automotive, Hydraulics and Aerospace industries, the cleanliness of the system parts and components before their assembly into the system is being addressed. The measurement of components and parts cleanliness is related to contaminant collection, analysis and data reporting and ISO Standard are continually being developed to control procedures. This Paper explains the processes in these standards and explains how similar procedures have been adapted to suit the requirements of the respective Industry. It also gives guidance and recommendations on the implementation of these standards, so that best use can be made of them.

• KSBB Journal
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• 제18권1호
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• pp.65-69
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• 2003

Pentoxifylline MIPs에서 시료와 기능성 단위체 사이에는 수소결합이 형성되었다. 수소결합의 능력은 분자구조상 질소원자의 위치에 의해 결정되어졌다. Pentoxifylline과 caffeine theophylline MIPs 모두는 구조상 유사한 시료들과 affinity가 증가하는 결과를 얻어냈다. 특히 caffiene-theophylline MIPs에서 높은 수치의 체류인자와 IF를 얻었다. 이러한 결과로 적합한 복합 주형분자를 사용할 때 우리가 원하는 목적시료만을 선택적으로 분리 할 수 있고 그러므로 solid phase extraction에 사용되기에 적합하다는 결과를 얻어냈다.

• Journal of Periodontal and Implant Science
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• 제40권5호
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• pp.227-231
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• 2010

Purpose: The healing process following tooth extraction apparently results in a pronounced resorption of the alveolar ridge. As a result, the width of alveolar ridge is reduced and severe alveolar bone resorption occurs. The purpose of this experiment is to clinically and histologically evaluate the results of using horse-derived bone mineral for socket preservation. Methods: The study comprised 4 patients who were scheduled for extraction as a consequence of severe chronic periodontitis or apical lesion. The extraction was followed by socket preservation using horse-derived bone minerals. Clinical parameters included buccal-palatal width, mid-buccal crest height, and mid-palatal crest height. A histologic examination was conducted. Results: The surgical sites healed uneventfully. The mean ridge width was $7.75{\pm}2.75\;mm$ at baseline and $7.00{\pm}2.45\;mm$ at 6 months. The ridge width exhibited no significant difference between baseline and 6 months. The mean buccal crest height at baseline was $7.5{\pm}5.20\;mm$, and at 6 months, $3.50{\pm}0.58\;mm$. The mean palatal crest height at baseline was $7.75{\pm}3.10\;mm$, and at 6 months, $5.00{\pm}0.82\;mm$. There were no significant differences between baseline and 6 months regarding buccal and palatal crest heights. The amount of newly formed bone was $9.88{\pm}2.90%$, the amount of graft particles was $42.62{\pm}6.57%$, and the amount of soft tissue was $47.50{\pm}9.28%$. Conclusions: Socket preservation using horse-derived bone mineral can effectively maintain ridge dimensions following tooth extraction and can promote new bone formation through osteoconductive activities.

• 식물병연구
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• 제20권1호
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• pp.15-20
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• 2014

A rapid, user-friendly and simple immune-chromatographic dipstick kit named 'rapid immune-gold strip' (RIGS) kit was developed in a novel single strip format to detect on-site detection of Tomato spotted wilt virus (TSWV). Immunoglobulin G (IgG) from polyclonal antisera raised in rabbits against TSWV was purified through protein-A affinity chromatography and then the purified TSWV-IgG was conjugated to colloidal gold nano-particles which served as a test line on nitrocellulose membrane. Protein A that non-specifically binds to TSWV antibody was used as a control line on the same strip. The diagnosis process with the TSWV-RIGS involves simply grinding the suspect plant sample in a bag that contains the extraction buffer and inserting the strip the bag. Results can be seen in 2-5 minutes. The flow of the complexes of gold particles coated with TSWV-IgG and a crude sap from TSWV-infected pepper, tobacco and tomato plants resulted in intensive color formed on the test lines proportional to the concentrations of TSWV. The RIGS-TSWV kit did not show any cross-reactions against other tomato-infecting viruses unrelated to TSWV. These results indicate that the TSWV-RIGS kit is highly sensitive and is not required for laboratory training and experience prior to testing. The TSWV-RIGS kit is suitable for on-site detection of suspect TSWV-infected plants as well as for laboratory diagnosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권6호
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• pp.528-532
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• 2010

Introduction: There are few reports on tooth eruption through Bio-Oss grafts. To our knowledge, there are no reports on whether teeth can erupt normally through the grafts. The aim of this study was to examine the effect of Bio-Oss grafts on tooth eruption in a canine model. Materials and Methods: In five 10-week-old dogs, the deciduous third mandibular molars in one jaw quadrant of each animal were extracted and the fresh extraction sockets were then filled with Bio-Oss particles (experimental side). No such treatments were performed on the contralateral side (control side). A clinical and radiological evaluation was carried out every other week to evaluate the eruption level of the permanent third mandibular premolars and compare the eruption levels between the two sides. Results: At week 4 after the experiment, the permanent third premolars began to erupt on both sides. At week 12, the crown of the permanent third premolar emerged from the gingiva on both sides. At week 20, the permanent third premolars on both sides erupted enough to occlude the opposing teeth. No significant differences were found between the control and experimental sides in terms of the eruption speed of the permanent third molars. Conclusion: These findings demonstrate that the grafting of Bio-Oss particles into the alveolar bone defects does not affect tooth eruption.

• 한국분말재료학회지
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• 제1권1호
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• pp.72-78
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• 1994

Two kinds of $U_3Si$ powders and $U_3Si$ dispersed nuclear fuel meats have been prepared by conventional comminution process and a newly developed rotating disk atomization process. In contrast to angular shape and broad size distribution of the conventionally processed powder, the atomized powder was spherical and showed narrow size distribution. For the atomized powder, the heat treatment time for the formation of $U_3Si$ by a peritectoid reaction was reduced to about one tenth, thanks to microstructure refinement by rapid cooling of about 5$\times$104 K/s. The extruding pressure of atomized $U_3Si$ powder and Al powder mixture was lower than that of comminuted $U_3Si$ and Al powder mixture. The elongation of the atomization processed fuel meats was much higher than that of the comminution processed fuel meats and remained over 10% up to 80wt.% of $U_3Si$ powder fraction in the fuel meats. It appears therefore that the loading density of $U_3Si$ in fuel meat can be increased by using atomized $U_3Si$ powder. The atomized spherical particles were randomly distributed, while the comminuted particles with angular and longish shape were considerably aligned along the extrusion direction. Along the transverse direction of the extraction the electrical conductivity of the atomization processed fuel meats was appreciably higher than that of comminution processed fuel meats. This tendency became pronounced as $U_3Si$ content increased. Because the thermal conduction which is believed to be proportioned to the electrical conduction in the nuclear fuel meats occurs in radial direction, the atomization processed fuel can be better used in research reactors where high thermal conductivity is required.

• 한국화재소방학회논문지
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• 제17권2호
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• pp.56-61
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• 2003

제연방식과 풍량에 따른 실내에 유입된 연기의 제연성능을 조사하기 위해 Fire Dynamics Simulator의 대와류모사를 사용하였다. 급기구와 배기구, 개구부가 있는 크기 2m X 2m X 2.4m의 실내에 급기방식과 배기방식, 급배기방식의 제연설비를 각각 가동했을 때 실내에 무작위로 분포한 입자의 감소율을 조사하였고, 급배기방식에서 풍량에 따른 입자의 감소율을 비교하였다. 세가지 제연방식 중 배기방식과 급배기방식은 제연성능에 차이가 없었으나, 개구부가 있는 경우에는 급기방식이 다른 두 제연방식에 비해 제연성능이 떨어졌다. 또 급배기방식에서 풍량이 감소하면 제연성능이 급격히 떨어지는 것으로 나타났다. 이 결과로부터 대형 개구부가 많은 지하철역 등에는 급기방식 대신에 급배기방식 또는 배기방식의 제연설비를 사용해야하며, 신속하게 연기를 배출하기 위해 풍량을 높게 할 필요가 있음을 알 수 있었다.

• KEPCO Journal on Electric Power and Energy
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• 제3권1호
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• pp.29-34
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• 2017

Leaching kinetics for extracting yttrium from the coal fly ash was investigated in the presence of sulfuric acid during extraction. The leaching kinetics of yttrium were conducted at reactant densities of 5~1,000 g coal fly ash per L of $1.0{\sim}10.0N\;H_2SO_4$, agitation speed of 250 rpm and temperature ranging from 30 to $90^{\circ}C$. As a result, the leaching kinetic model was determined in a two-step model based on the shrinking core model with spherical particles. The first step was proceeded by chemical reaction at ash surface, and the second step was proceeded by ash layer diffusion because the leaching conversion of yttrium by the first chemical reaction increases with increased the time irrelevant to the temperature whereas it increases with increased the leaching temperature. The activation energy of the first chemical leaching step was determined to be $1.163kJmol^{-1}$. After the first chemical reaction, the activation energy of ash layer diffusion leaching was derived to be $41.540kJmol^{-1}$. The optimum conditions for leaching the yttrium metal of 60 % were found to be the slurry density of 250 g fly ash per L of $H_2SO_4$, solvent concentration of $2.0N\;H_2SO_4$, second step leaching of temperatures of $30^{\circ}C$ for 3 hours and then $90^{\circ}C$ for 3 hours at agitation rate of 250 rpm.

• 한국응용과학기술학회지
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• 제34권3호
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• pp.623-630
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• 2017

본 연구는 구기자 종자를 초임계유체 추출한 후 in vitro 미백활성과 항균 실험을 실시하였으며, 추출물을 에멀션에 적용하여 안정성 평가를 수행하기 위해 pH, 점도, 에멀션 입자를 관찰하였다. 그 결과 미백활성의 경우 $750{\mu}g/mL$에서 81.86 %의 미백 활성을 나타내었으며, 항균효과의 경우 Staphylococcus epidermidis, Candida albicans, Escherichia coli 균에서 항균효과가 나타났다. 또한 추출물을 함유한 에멀션 물리적 안정성 평가에서 점도와 pH가 28일 동안 큰 변화가 없었으며 유화물 입자 관찰 시 경시변화에 따른 합일과 분리현상이 확인되지 않았다. 이러한 결과는 화장품소재로서의 구기자 씨앗 추출물이 유용되게 활용될 수 있는 가능성을 가진 것으로 평가된다.

• Journal of Periodontal and Implant Science
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• 제47권4호
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• pp.194-210
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• 2017

Purpose: The aim of the present study was to evaluate the healing of post-extraction sockets following alveolar ridge preservation clinically, radiologically, and histologically. Methods: Overall, 7 extraction sockets in 7 patients were grafted with demineralised bovine bone mineral and covered with a porcine-derived non-crosslinked collagen matrix (CM). Soft tissue healing was clinically evaluated on the basis of a specific healing index. Horizontal and vertical ridge dimensional changes were assessed clinically and radiographically at baseline and 6 months after implant placement. For histological and histomorphometric analysis, bone biopsies were harvested from the augmented sites during implant surgery 6 months after the socket preservation procedure. Results: Clinically, healing proceeded uneventfully in all the sockets. A trend towards reduced horizontal and vertical socket dimensions was observed from baseline to the final examination. The mean width and height of resorption were 1.21 mm (P=0.005) and 0.46 mm (P=0.004), respectively. Histologically, residual xenograft particles ($31.97%{\pm}3.52%$) were surrounded by either newly formed bone ($16.02%{\pm}7.06%$) or connective tissue ($50.67%{\pm}8.42%$) without fibrous encapsulation. The CM underwent a physiological substitution process in favour of well-vascularised collagen-rich connective tissue. Conclusions: Socket preservation using demineralised bovine bone mineral in combination with CM provided stable dimensional changes of the alveolar ridge associated with good reepithelialisation of the soft tissues during a 6-month healing period.