• 한국연초학회지
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• 제27권2호
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• pp.163-170
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• 2005

A theoretical model for predicting the capability curve of cellulose acetate filter is derived. The pressure drop is expressed as a function of the filter dimensions, the tow fiber characteristics, the filter weight, the fluid flow rate, and a filter fiber factor. Where, the filter fiber factor is affected by the distribution of the tow fibers within the filter, the relative orientations of the tow fibers, and their cross-sectional shapes. The minimum and maximum fraction of solids in capability curves determined from experimental data. Also, the filter fiber factor is expressed as a function of the filter length, tow fiber length, and tow fiber diameter. Capability curves predicted by the suggested model in this work correspond well with capability curves by experimental data.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권4호
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• pp.460-465
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• 2013

Electrical equipments of nuclear power plant are divided into class 1E and non-class 1E. Electrical equipment and systems that are essential to emergency reactor shutdown, containment isolation, reactor core cooling, and containment and reactor heat removal, are classified as class 1E. batteries of nuclear power plant are divided into four channels, which are physically and electrically separate and independent. The battery bank of class 1E DC power system of the nuclear power plant use lead-acid batteries in present. The lead acid battery, which has a high energy density, is the most popular form of energy storage. Kt factor of lead-acid battery is used to determine battery size and it is one of calculatiing coefficient for capacity. this paper analyzes Kt factor of lead-acid battery for the DC power system of nuclear power plant. In addition, correlation between Kt parameter and peukert's exponent of lead-acid battery for nuclear plant are discussed. The analytical results contribute to optimize of determining size Lead-acid battery bank.

• Journal of Ginseng Research
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• 제32권4호
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• pp.315-323
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• 2008

In the previous studies, we isolated the compound K rich fractions (CKRF) and showed that CKRF inhibited Toll-like receptor (TLR) 4- or TLR9-induced inflammatory signaling. To extend our previous studies,1) we investigated the molecular mechanisms of CKRF in the TLR4-associated signaling via nuclear factor (NF)-${\kappa}B$, and in vivo role of CKRF for induction of tolerance in lipopolysaccharide (LPS)-induced septic shock. In murine bone marrow-dervied macrophages, CKRF significantly inhibited the induction of mRNA expression of proinflammatory mediators such as tumor necrosis factor-${\alpha}$, interleukin-6, cyclooxygenase-2, and inducible nitric oxide synthase. In addition, CKRF significantly attenuated the transcriptional activities of TLR4/LPS-induced NF-${\kappa}B$. Nuclear translocation of NF-${\kappa}B$ in response to LPS stimulation was significantly abrogated by pre-treatment with CKRF. Furthermore, CKRF inhibited the recruitment of p65 to the interferon-sensitive response element flanking region in response to LPS. Finally, oral administration of CKRF significantly protected mice from Gram-negative bacterial LPS-induced lethal shock and inhibited systemic inflammatory cytokine levels. Together, these results demonstrate that CKRF modulates the TLR4-dependent NF-${\kappa}B$ activation, and suggest a therapeutic role for Gram-negative septic shock.

• Journal of Veterinary Science
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• 제24권5호
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• pp.69.1-69.11
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• 2023

Background: Kalkitoxin (KT) is an active lipopeptide isolated from the cyanobacterium Lyngbya majuscula found in the bed of the coral reef. Although KT suppresses cell division and inflammation, KT's mechanism of action in vascular smooth muscle cells (VSMCs) is unidentified. Therefore, our main aim was to investigate the impact of KT on vascular calcification for the treatment of cardiovascular disease. Objectives: Using diverse calcification media, we studied the effect of KT on VSMC calcification and the underlying mechanism of this effect. Methods: VSMC was isolated from the 6 weeks ICR mice. Then VSMCs were treated with different concentrations of KT to check the cell viability. Alizarin red and von Kossa staining were carried out to examine the calcium deposition on VSMC. Thoracic aorta of 6 weeks mice were taken and treated with different concentrations of KT, and H and E staining was performed. Real-time polymerase chain reaction and western blot were performed to examine KT's effect on VSMC mineralization. Calcium deposition on VSMC was examined with a calcium deposition quantification kit. Results: Calcium deposition, Alizarin red, and von Kossa staining revealed that KT reduced inorganic phosphate-induced calcification phenotypes. KT also reduced Ca⁺⁺-induced calcification by inhibiting genes that regulate osteoblast differentiation, such as runtrelated transcription factor 2 (RUNX-2), SMAD family member 4, osterix, collagen 1α, and osteopontin. Also, KT repressed Ca²⁺-induced bone morphogenetic protein 2, RUNX-2, collagen 1α, osteoprotegerin, and smooth muscle actin protein expression. Likewise, Alizarin red and von Kossa staining showed that KT markedly decreased the calcification of ex vivo ring formation in the mouse thoracic aorta. Conclusions: This experiment demonstrated that KT decreases vascular calcification and may be developed as a new therapeutic treatment for vascular calcification and arteriosclerosis.

• 한국연초학회지
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• 제32권1호
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• pp.19-27
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• 2010

The aim of this study is to compare the sensitivity of both two NCI-H292 and A549 cell types to acute inflammatory responses induced by cigarette smoke. For this, we treated two kinds of smoke fractions derived from 2R4F reference cigarettes: total particulate matter(TPM) collected onto a Cambridge filter pad and gas/vapor phase(GVP) prepared by bubbling through in buffer solution. When we measured cellular cytotoxicity by neutral red uptake assay after treatment for 24 hours, TPM and GVP induced cytotoxic effect in a dose-dependent manner in the range of 10-$100{\mu}g$/mL and 60-$300 {\mu}g$/mL., respectively, in both cell types without any cellular difference. Additionally, when we examined acute inflammatory responses by analyzing cytokines secreted into culture media including tumor necrosis factor-$\alpha$ (TNF-$\alpha$), interleukin-8(IL-8), and transforming growth factor-$\alpha$(TGF-$\alpha$) as well as matrix metalloproteinase-1(MMP-1), the treatment with smoke fractions increased those marker proteins in a dose-dependent manner in NCI-H292. Meanwhile, in A549 cells only MMP-1 was observed to be increased in a dose-dependent fashion. Collectively, our data indicate that NCI-H292 cell type is more sensitive to cigarette smoke-induced inflammatory response than A549 cells. This suggests that NCI-H292 could be useful as an in vitro evaluation tool to assess harmful effects of cigarette smoke.

• 한국심리학회지:학교
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• 제17권2호
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• pp.165-180
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• 2020

본 연구의 목적은 다층적 행동지원 모형을 적용하고 있는 학교차원 긍정적 행동지원(School-Wide Positive Behavior Supports, SWPBS)을 국내 학교현장에서 근거기반 실천으로 보급하기 위해 개별화지원에 해당하는 3차 지원의 실행충실도 평가도구를 개발해 타당화하는 것이었다. 3차 지원 실행충실도 평가도구를 개발하기 위해 문헌 개관 및 전문가 내용 타당도 검증을 통해 핵심 평가요소 6개 요인으로 구성된 37개의 예비문항을 선정하였다. 이후 학교차원 긍정적 행동지원 실행 경험이 있는 현직 교사 185명(남 52명, 여 133명)을 대상으로 3차 지원 실행충실도 척도, 개별화지원 척도, 학교풍토 척도, 학생지도 척도, 긍정적 행동지원 효과성 척도로 구성된 설문지를 배포해 자료를 수집하였다. 탐색적 요인분석에서 각 하위요인에 4문항으로 구성된 5요인 구조(요인 1: 개별화지원 계획의 점검 및 평가, 요인 2: 정신건강 서비스 연계를 통한 지원, 요인 3: 위기관리 계획, 요인 4: 문제행동 평가, 요인 5: 개별화지원 팀구성)의 총 20문항이 최종 문항으로 선정되었다. 또한 내적 합치도는 전체 문항 α=.950, 하위요인은 α=.888 ~ .954로 모두 양호하였다. 상관분석에서 3차 지원 실행충실도 척도는 개별화지원 척도, 학교풍토 척도, 학생지도 척도, 긍정적 행동지원 효과성 척도와 각각 유의미한 상관을 나타내면서 양호한 수렴타당도를 나타내었다. 마지막으로, 확인적 요인분석에서 5요인 구조의 모형 적합도는 양호하였고, 신뢰도 및 타당도가 안정적인 것으로 나타났다. 따라서 SWPBS의 실행충실도를 점검하고 평가하는 데 본 척도가 신뢰롭고 타당하게 사용될 수 있을 것으로 보인다. 또한 한국형 3차 지원 실행충실도 척도가 국내 학교현장에서 SWPBS를 근거기반의 행동적 개입으로 활용하는 데 기여할 수 있을 것이다.

• 한국지반공학회논문집
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• 제19권6호
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• pp.169-179
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• 2003

연약지반에 축조되는 구조물 설계에 매우 중요한 지반 특성치인 점토지반의 비배수 전단강도를 깊이에 따라 연속적으로 측정할 수 있는 현장 원위치 시험법으로서 피에조 콘의 활용도가 점점 높아지고 있다. 피에조 콘 시험으로 추정되는 비배수 강도의 신뢰성은 이에 적용되는 콘 계수 값의 신뢰성에 크게 의존한다. 콘 계수에 대한 여러 연구자들의 제안이 우리의 실정에 맞는지 검증하고 점토지반의 특성에 따른 콘 계수 값의 변화 특성을 파악하여 콘 계수 선정에 대한 합리적인 기준을 마련하는 것이 이 연구의 목적이다. 이 연구는 경남 양산물금 지역의 해성점토층을 대상으로 피에조 콘 시험과 비교란 시료에 대한 실내 전단강도시험(일축압축시험, 비압밀 비배수 삼축압축시험)과 압밀시험을 실시하였다. 시험 결과를 이용하여 콘 계수와 점토의 여러 역학적 특성치(비배수 전단강도, 선행압밀압력, 소성지수, 간극수압비, 강성지수, 마찰비)의 관계를 고찰하여 콘 계수 값의 합리적 선정을 위한 기준을 마련하고자 하였다. 연구 결과로부터 얻은 결론으로서는, 상관관계가 비교적 높은 특성치의 짝은 비배수 전단강도와 콘 계수$(N_{kt}, N_{ke}, N_{\Delta u})$, 선행압밀압력과 $(N_{kt}, N_{ke})$, 간극수압비(B$_{q}$ )와 $(N_{ke}, N_{\Delta u})$이었고 선행압밀압력과 $(N_{\Delta u}), B_q와 (N_{kt})$는 상관 관계가 나타나지 않았으며, 소성지수, 강성지수, 그리고 마찰비도 콘 계수와 상관 관계가 없는 것으로 나타났다. 또한, 비압밀 비배수(UU) 삼축압축시험으로 구한 점토의 비배수 전단강도를 기준으로 할 때, 여러 제안자들이 제안한 피에조 콘 시험결과를 이용한 비배수 전단강도 추정에서 $(N_{\Delta u})$가 다른 두개의 콘 계수보다 선행압밀압력의 크기에 상관없이 변화폭, 표준편차 및 분산도가 모두 작아서 신뢰성이 가장 높게 나타났다.

• 한국연초학회지
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• 제26권2호
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• pp.168-178
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• 2004

Uncertainty of final measurement results considering main uncertainty sources being in nicotine of mainstream smoke was estimated. This study was accomplished by using the ISO 'The Guide to the Expression of Uncertainty in Measurement'. Using the two point re-calibration method, uncertainty for nicotine concentration was calculated considering the uncertainty sources of each step. The concentration and uncertainty of nicotine in mainstream smoke was estimated as $153.95{\pm}17.84\;{\mu}g/mL\;(0.77\pm0.089 mg/cig)$. The expanded uncertainty was $17.84 {\mu}g/mL(\pm0.089 mg/cig).$ The reported expanded uncertainty of the measurement is stated as the standard uncertainty of measurement multiplied by a coverage factor of 2, which for a normal distribution corresponds to a coverage probability of approximately $95\%$ The former expression indicates the conversion concentration into the sample.

• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.154-156
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• 2006

Trace metals in honey have an influence on the taste of honey along with pollens. Western bee honeys, which are mostly collected from acacia, have less than 0.1% of ash. Savor of Korean native-bee honey is thought to be due to the difference of the contents of trace metals. Korean native-bee honeys collected from Jirisan District, which is the greatest producing area of native-bee honey in Korea, showed high contents of ash. Korean native-bee honeys from the districts other than Jirisan District also showed similar results($0.44{\sim}0.83%$ of ash) to those from Jirisan District. Potassium was found to be the principal factor of high content of ash with over 85% of trace metals in ash.

• 한국연초학회지
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• 제29권1호
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• pp.1-7
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of flue-cured tobacco as soon as possible. The data of eight chemical and five physical properties were collected from "Analysis of physical and chemical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 through 2006. Data of climatic factors from April to July in 10 districts were collected from Korea Meteorological Adminstration. Except for yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, in nicotine content, and in filling value, 90% in total nitrogen content, and 70% in total sugar content. These results suggest that the regression equations may be useful to predict the average content of twelve grades for eight chemical and four physical properties by climatic factors during the growing season of flue-cured tobacco at the beginning of August.