• 한국안전학회지
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• 제25권5호
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• pp.15-21
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• 2010

Regenerative Energy Storage System(ESS) is a system that saves regenerative energy which generated instantly in the regenerative braking of Electric Multiple Unit(EMU) and disappear, and reuse the stored energy when EMU is in powering. Such system related to a research field of renewable energy which emerged concerning climate change and high oil prices. In the case of existing domestic rolling stock, about 25% to 30% of generated regenerative energy is restored to power source and is regarded as direct factor of raising catenary voltage. Such rapid change of catenary voltage is a cause of the failure of EMU's electronic equipment and lowering its reliability and is also a cause of train's fault occurred by tripping circuit breaker. In this paper, we intend to investigate the effect on blending characteristics of electric-braking and pneumatic-braking whether the regenerative energy storage system is used or not in urban transit DC 1,500V feeding system, while trains run. And we also intend to investigate its effect on stabilization of the blending, fluctuation of catenary voltage and various electric equipments.

• 대한기계학회논문집
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• 제10권4호
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• pp.463-470
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• 1986

본 연구에서는 절삭공정 중 발생하는 공구의 접촉이탈 현상에 의하여 공작 물의 절삭된 표면중에 한회전 및 그 이전 회전에 절삭된 절삭면의 형상이 현재의 절삭 깊이에 영향을 미치는 다중재생효과(multiple regenerative effect)가 존재하는 선삭 작업에서 공구의 착탈현상을 고려한 비선형채터(nonlinear chatter)를 공작기계의 생 산성의 관점에서 절삭공정의 특성을 고려하여 해석하였으며, 수동제어기의 일종인 임 펙트댐퍼를 절삭공정에 응용하여 절삭작업중에 공작기계의 안정성향상 뿐만 아니라 생 산성의 증가효과를 규명하였다.아울러 댐퍼자체의 설계변수에 따른 채터 억제효과 를 고려하여 최적의 댐퍼를 설계하는 방법을 제시하였다.

• Medical Lasers
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• 제9권2호
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• pp.134-141
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• 2020

The use of stem cell therapy to treat various diseases has become a promising approach. The ability of stem cells to self-renew and differentiate can contribute significantly to the success of regenerative medical treatments. In line with these expectations, there is a great need for an efficient research methodology to differentiate stem cells into their specific targets. Photobiomodulation (PBM), formerly known as low-level laser therapy (LLLT), is a relatively non-invasive technique that has a therapeutic effect on damaged tissue or cells. Recent advances in adapting PBM to stem cell therapy showed that stem cells and progenitor cells respond favorably to light. PBM stimulates different types of stem cells to enhance their migration, proliferation, and differentiation in vitro and in vivo. This review summarizes the effects of PBM on targeted differentiation across multiple stem cell lineages. The analytical expertise gained can help better understand the current state and the latest findings in PBM and stem cell therapy.

• Restorative Dentistry and Endodontics
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• 제40권3호
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• pp.179-187
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• 2015

Traditionally, apexification has been used to treat immature permanent teeth that have lost pulp vitality. This technique promotes the formation of an apical barrier to close the open apex so that the filling materials can be confined to the root canal. Because tissue regeneration cannot be achieved with apexification, a new technique called regenerative endodontic treatment was presented recently to treat immature permanent teeth. Regenerative endodontic treatment is a treatment procedure designed to replace damaged pulp tissue with viable tissue which restores the normal function of the pulp-dentin structure. After regenerative endodontic treatment, continued root development and hard tissue deposition on the dentinal wall can occur under ideal circumstances. However, it is difficult to predict the result of regenerative endodontic treatment. Therefore, the purpose of this study was to summarize multiple factors effects on the result of regenerative endodontic treatment in order to achieve more predictable results. In this study, we investigated the features of regenerative endodontic treatment in comparison with those of other pulp treatment procedures and analyzed the factors that have an effect on regenerative endodontic treatment.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.154-156
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• 2008

A prototype of the desiccant cooling system with a regenerative evaporative cooler was built and tested for the performance evaluation. The regenerative evaporative cooler is to cool a stream of air using evaporative cooling effect without an inc6rease in the humidity ratio. It is comprised of multiple pairs of dry and wet channels and the evaporation water is supplied only to the wet channels. By redirecting a portion of the air flown out of the dry channel into the wet channel, the air can be cooled down to a temperature lower than its inlet wet-bulb temperature at the outlet end of the dry channels. Incorporating a regenerative evaporative cooler eliminates the need for deep dehumidification in the desiccant rotor that is necessary to achieve low air temperature in the system with a direct evaporative cooler. Subsequently, the regenerative evaporative cooler enables the use of low temperature heat source to regenerate the dehumidifier permitting the desiccant cooling system more beneficial compared with other thermal driven air conditioners. At the ARI condition with the regeneration temperature of $60^{\circ}C$, the prototype showed the cooling capacity of 4.4 kW and COP of 0.75.

• 생명과학회지
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• 제26권7호
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• pp.835-846
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• 2016

항암제 내성은 화학적 치료법의 가장 큰 난관의 하나로 효과적인 항암치료를 위해서 반드시 극복 되야 할 문제이다. ABCG2는 다약제 내성과 이를 특징으로 하는 암 줄기세포와의 연관성도 매우 높다고 보고되고 있다. 최근 암용해 바이러스가 다양한 암종과 항암제내성을 보이는 암 치료에 새로운 대안으로 대두되고 있다. 이에 본 연구에서는 항암제 내성 암 치료를 위해 새로운 암용해 백시니아 바이러스 SLJ-496을 개발하였다. 본 연구에서, cytophathic effect, plaque assay, viability assay를 통하여 야생형 바이러스에 비교하여 증가된 종양친화성을 확인하였다. 또한, invitro 환경에서 대장암 세포주(HT-29, HCT-116, HCT-8)를 비롯하여 위암 세포주(AGS, NCI-N87, MKN-28), 간암 세포주(SNU-449, SNU-423, SNU-475, HepG2) 그리고 난치성 암 종인 중피 세포종(NCI-H226, NCI-H28, MSTO-211h)에서 유의적인 세포독성효능을 입증하였다. ABCG2의 발현이 높은 HT-29세포의 3차원 구형배양을 통하여 ABCG2와 암줄기세포 특성의 연관성을 증명하였으며, 항암제 내성세포 모델에서 SLJ-496GFP가 유의한 세포독성을 나타내며 암세포내 복제능을 가지는 것을 입증하였다. ABCG2를 과발현 시킨 세포주 내 야생형 바이러스에 비교하여 유의적으로 낮은 세포 생존율을 증명하였으며, 바이러스의 복제능 또한 검증하였다. 또한, 지속적인 항암제 투여를 통하여 ABCG2의 발현이 높은 항암제 내성 세포주에서의 항종양 효능 또한 입증하였다. 이상의 결과를 토대로 ABCG2가 과발현 된 암 줄기세포 및 항암제 내성에 새로운 항종양 바이러스 SLJ-496 백시니아 바이러스 치료법이 새로운 치료 대안이 될 수 있을 것이라 제안한다.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.407-417
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• 1995

In order to evaluate the effect of platelet-derived growth factor(PDGF-BB) and guided tissue regeneration(GTR) technique on the regeneration of destructed periodontal tissue,intentional through-and-through furcation defects(4mm in height) were made on both mandibular 2nd and 4th premolars of 8 adult male dogs(30-40lb). Experimental group 1 was composed of the premolars that were treated by only topical application of PDGF-BB with 0.05M acetic acid without any barrier membrane. Experimental group 2 was composed of the premolars that were treated by GTR with expanded polytetrafluoroethylene membrane(ePTFE : Gore-tex periodontal material, USA). Experimental group 3 was composed of the premolars that were treated by GTR with ePTFE after topical application of PDGFBE. Control group was composed of the premolars that were treated by coronally positioned flap operation only without use of PDGF-BB and ePTFE membrane. All ePTFE membranes were carefully removed 4 weeks after regenerative surgery, and all experimental animals were sacrificed 8 weeks after regenerative surgery. The light microscopic findings were as follows ; (1) In experimental group 1, rapid new bone formation along the-root surface with multiple ankylosis and root resorption by multinucleated giant cells, and dense connective tissue in the central portion of the furcation defects were observed. (2) In experimental group 2, it was observed that the furcation defects were filled with newly formed bone, Sharpey's fibers were embedded into new cementum on root dentin of furcation fornix area, but the central portion and the area under furcation fornix were still filled with dense connective tissue. (3) In experimental group 3, the furcation defects were regenerated with newly formed dense bone and regular periodontal ligament with Sharpey's fibers embedded into newly formed cementum and bone underneath fornix area. (4) In control group, unoccupied space, apical migration of epithelium, dense infiltration of inflammatory cells in subepithelial connective tissue in relation to heavy plaque accumulation, and root resorption by inflammatory reaction were shown, but any new cementum formation on resorbed dentin surface could not be observed. The present study demonstrated that the combined therapy of PDGF-BB and GTR could enhance the regeneration of destructed periodontal tissue.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권2호
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• pp.386-404
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• 2013

In broadband satellite multimedia (BSM) system, burst time plan (BTP) is always periodically generated. We find that this method can have a great effect on the system response ability to bandwidth requests. A general analysis model of BTP generation method is given. An optimized BTP generation (O-BTPG) method is presented by deducing the optimal bandwidth allocation period (BAP) and bandwidth allocation latency (BAL) without considering the signaling overhead caused by BTP. Then a novel asynchronous BTP generation (A-BTPG) method in which the BTP is generated asynchronously according to the traffic load from users' bandwidth requests is proposed. Simulation results show that A-BTPG can flexibly realize a trade-off between the system response ability and BTP signaling overhead. What's more, it can be widely used in various regenerative onboard switching BSM systems.

• Food Science and Biotechnology
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• 제14권4호
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• pp.474-478
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• 2005

Because it possesses anti-inflammatory, antifungal, antiviral, and tissue regenerative properties, propolis has been used for thousands of years in folk medicine for multiple purposes. Although the antimicrobial activity of propolis has already been demonstrated, very few studies have been conducted on bacteria of clinical relevance in dentistry. The aim of this study is to evaluate the antimicrobial, anti-inflammatory, and anti-oxidative activities of 0.1% and 1.0% propolis, both of water-extracted (proAQ) and ethanol-extracted (proAL) propolis, for industrial applications. In studies of antimicrobial activity, the growth of Staphylococcus aureus ATCC 35556, Salmonella enteritidis ATCC 12021, Escherichia coli O157:H7, and Candida parapsilosis KCCM 35428, all general food or clinical pathogens, were tested. The culture medium used was trypticase soy broth including 0.6% yeast extract; after 6 hr of incubation, the turbidities were measured at 620 nm with a spectrophotometer. The results indicate that the antimicrobial effects of both 1.0% proAQ and 1.0% proAL were greater against the growth of S. aureus ATCC 35556 and C. parapsilosis KCCM 35428 rather than those of S. enteritidis ATCC 12021 and E. coli O157:H7. Additionally, it appears that the anti-inflammatory effects of proAL are greater than those of proAQ. The anti-inflammatory effects were evaluated by measurement of the inhibition of hyaluronidase activity in vitro. At a 1% concentration, the anti-inflammatory effects of proAL were greater than those of proAQ. Finally, the anti-oxidative effects of 1% and 10% solutions of each extract sample were measured according to the TBA method at $40^{\circ}C$ for 1, 2, 3, and 5 days and were compared with 1.0% BHT. The results indicate that the anti-oxidative effects at 0.1% for both proAQ and proAL were not significantly different than the anti-oxidative effects at 1.0% BHT (p<0.05). Thus, it appeared that the alcohol-extracted propolis had greater antimicrobial, anti-inflammatory, and anti-oxidative effects than the water-extracted propolis. This is based on the presumption that major biofunctional components were fat-soluble, rather than water-soluble.

• Journal of Nutrition and Health
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• 제41권5호
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• pp.391-401
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• 2008

캐피어 원말은 유산균, 효모, 다당 및 여러 영양성분을 다량 함유하고 있으며 장기능 개선 효능을 살펴보기 위하여 3주령의 수컷 흰쥐 (Sprague-Dawley)를 4군으로 나누어 정상대조군 (N군), DSS투여 대조군 (DC군)과 두 군의 캐피어 투여군으로 하여 대조군 사료와 캐피어 원말을 각각 1.5%와 3.0% 혼합한 사료로 3주간 사육하였다. 이 후 DSS투여 대조군과 캐피어 투여군들에 5일간 2% DSS 음용수 동일한 양을 투여하여 경미한 대장염을 유도하였다. 대장염 유도 후 희생하여 소장 단백질 및 DNA 함량, 혈장 및 결장의 조직검사와 결장조직에서 TBARS와 MPO 활성, 혈장 백혈구에서의 DNA 손상 정도를 측정하였다. 실험 자료는 Windows용 SPSS package program version12.0을 이용하여 통계 처리하였고, 네 군간의 평균값의 차이를 검증하기 위하여 일원배치 분산분석 (one-way ANOVA)을 한 후, Duncan's multiple range test로 변인간의 차이를 검증하였다. DSS 투여군 들에서 변 수분함량이 증가하고 음용수 섭취량이 증가하는 경향과 함께 결장의 조직검사 결과 DSS 투여군에서는 염증과 부종 증상을 관찰할 수 있었으며 식이무게의 3% 캐피어 원말 투여군에서는 재생성 변화를 볼 수 있었다. DSS를 투여받은 군들의 소장 점막 단백질 함량은 감소하는 경향을 보였으며 캐피어 3.0%식이섭취한 군들에서는 증가하는 경향을 보였으나 DNA함량에서는 차이를 볼 수 없었다. DSS 투여군에서는 결장조직의 TBARS 값이 유의적으로 증가하였으며 캐피어 투여군에서는 감소하였으나 캐피어 투여 용량에 따른 차이는 보이지 않았다. 혈장 TBARS와 결장조직의 MPO 활성은군 간에 유의한 차이가 없었다. DSS 투여군에서는 혈액 백혈구 DNA의 tail length가 유의하게 증가하였으며 캐피어 투여군에서는 감소하였다. 따라서 약 4주간 캐피어 원말의 투여는 2%의 DSS로 경미한 대장염을 유도한 흰쥐에서 결장 조직의 산화적 스트레스에 대한 저항력을 증가시켜 대장점막을 보호할 수 있는 기능이 있음을 확인할 수 있었다.