• 한국건설순환자원학회논문집
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• 제7권3호
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• pp.271-278
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• 2019

철근 콘크리트 구조물에서 철근의 부식은 내구성 문제를 발생시키고 있으며, 이에 대한 대책의 하나로 에폭시 도막철근이 사용되고 있다. 그러나 에폭시 도막철근을 사용하는 경우 철근 부식에 대한 저항성능은 우수하나 철근에 에폭시 도막을 함으로써 콘크리트와의 부착력이 일반철근에 비하여 감소하는 단점이 있다. 따라서 부착성능에 대한 실험적인 확인이 필요하여 ACI 408R에서 제시하는 대표적인 실험 방법인 휨 부재를 통하여 부착거동을 연구할 수 있는 보-단부 test와 직접인발을 통해 부착 특성을 분석하는 Pullout test를 통하여 부착성능을 평가하였다. 에폭시 도막 철근의 부착실험은 휨 부재실험과 직접인발 실험 모두 지름 13, 19mm의 철근에 대한 콘크리트 도막두께를 철근 지름의 3배로 하여 수행되었다. 실험 결과 에폭시 도막철근의 부착강도는 철근의 지름이 증가할수록 에폭시 도막 철근과 일반철근의 부착강도차이가 증가하였고 파괴형상은 모두 뽑힘 파괴를 나타내었다. 또한, 직접인발시험으로 구한 부착-미끌림 관계에 근거하여 유한요소해석을 수행하고, 휨 실험결과와 비교하였다. 부착성능을 평가하는 방법으로 실제 구조물에 거동을 모사를 위해서 직접인발시험보다 휨 부재시험이 보다 유용한 것으로 사료된다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.176-184
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• 2002

Objective; Antistress effect of Korean red ginseng (RG) on postmenopausal women with severe climacteric syndrome (CS) were evaluated from the viewpoint of traditional KAMPO-medicine and Western medicine. Methods; All patients with CS were treated with daily oral administration of 6g RG for 30 days. Nine patients with CS were evaluated with the use of diagnostic scores for KI-deficiency (deficiency of vital energy) and OKETSU (blood stagnation) syndrome from the viewpoint of KAMPa-medicine. In the same patients with CS, peripheral blood levels of $\beta$-endorphin and total plasminogen activator inhibitor-1 (t-PAI-1) were measured before and after treatment with RG. In another group, 12 patients with CS, psychological test using CMI, STAI and SDS were performed from the viewpoint of Western medicine. Stress related hormones, such as ACTH, cortisol and DHEA-S in those 12 patients with CS were also measured before and after treatment with RG. Results; KI-deficiency score and OKETSU score in patients with CS were significantly (p<0.001) higher than those in patients without CS. After treatment with RG, both scores were markedly (p<0.001) decreased compared to before treatment with RG. ${\beta}-endorphin$ levels in patients with CS were significantly (p<0.05) higher than those in patients without CS. Total PAI-I levels in patients with CS were increased before treatment with RG. No significant difference, however, were observed between patients with and without CS. After treatment with RG, both levels of ${\beta}-endorphin$ and total PAI-l in patients with CS were significantly (p<0.01 and p<0.05, respectively) decreased compared to before treatment with RG. CMI and STAI scores in patients with CS were significantly (p<0.05) higher than those in patients without CS. SDS scores in patients with CS were also markedly (p<0.001) higher than in those without CS. After treatment with RG, all scores decreased within normal range. DHEA-S levels in patients with CS were about a half of those without CS. Consequently, cortisol/DHEA-S (C/D) ratio was significantly (p<0.001) higher in patients with CS than in those without CS. Although the decreased DHEA-S levels were not restored to the levels in patients without CS, the C/D ratio decreased significantly (p<0.05) after treatment with RG. Conclusion; Reinforcement of vital energy and improvement of stagnant blood circulations by oral administration of RG were elucidated from the viewpoint of traditional KAMPO-medicine. From the viewpoint of Western medicine, effect of RG on postmenopausal women with CS seemed to be brought about in part by not only an improvement of psychoneuroendocrine dysfunctions but also an amelioration of blood coagulation systems.

• 대한화장품학회지
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• 제31권4호
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• pp.311-321
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• 2005

차(Camellia sinensis)는 세계적으로 애용되는 음료이다. 그 중, 아시아권에서 주로 소비되는 녹차는 다양한 생리활성을 가지고 있어 화장품, 기능성식품을 위한 기능성 소재로서 선호되고 있다. 녹차의 피부에 대한 활성은 세포보호에서부터 피부 기질 단백질의 합성까지 다양하게 나타난다. 녹차 폴리페놀(green tea polyphenols; GTPs)은 활성을 나타내는 주성분으로서 항산화 활성 이외에 항암, 항염증, 피부면역능 저하방지활성 등을 보이며, 세포내 신호전달 경로에도 관여한다 GTPs는 표피각질형성세포에서 자외선 조사에 의한 산화 스트레스를 감소시키고, 그에 따르는 mitogen-activated protein kinase (MAPK) 신호전달과 세포사멸을 억제한다. 또한, 같은 세포에서 tumor necrosis factor alpha $(TNF{\alpha})$나 다른 화학물질에 의해 cyclooxygenase-2(COX-2), interleukin-8 (IL-8) 및 vascular endothelial growth factor (VEGF) 같은 염증매개물질이 유발되는 것을 막아준다. 또한, GTPs는 등물실험에서 화학물질이나 자외선에 의한 피부암의 발생도 억제하는데, 경구투여 외에 경피투여로도 효과가 있었다. 피부보호작용 이외에도 GTPs는 각질형성세포의 분화촉진, 노화된 피부세포의 증식능 회복, 피부기질단백질의 분해억제 등의 기능이 있으며, 피부세포에서의 기질단백질 생합성을 직접적으로 촉진하기도 한다. 녹차성분이 보이는 이러한 피부에 대한 활성은, 제형 측면에서의 연구가 진행되어 감에 따라 보다 효과적인 피부를 위한 소재로서의 사용 가능성을 더욱 높여주고 있다.

• 국제초고층학회논문집
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• 제10권4호
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• pp.335-344
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• 2021

In structural engineering practice, understanding the performance of composite columns under extreme loading conditions such as high-rise bulding, long span and heavy loads is essential to accuratly predicting of material responses under severe loads such as fires or earthquakes. Hitherto, the combined effect of partial axial loads and subsequent elevated temperatures on the performance of hollow steel column filled fly ash concrete have not been widely investigated. Comprehensive test was carried out to investigate the effect of elevated temperatures on partial axially loaded square hollow steel column filled fly ash concrete as reported in this paper. Four batches of hollow steel column filled fly ash concrete ( 30 percent replacement of fly ash), (HySC) and normal concrete (CFHS) were subjected to four different load levels, n_f of 20%, 30%, 40% and 50% based on ultimate column strength. Subsequently, all batches of the partially damage composite columns were exposed to transient elevated temperature up to 250℃, 450℃ and 650℃ for one hour. The overall stress - strain relationship for both types of composited columns with different concrete fillers were presented for each different partial load levels and elevated temperature exposure. Results show that CFHS column has better performance than HySC at ambient temperature with 1.03 relative difference. However, the residual ultimate compressive strength of HySC subjected to partial axial load and elevated temperature exposure present an improvement compared to CFHS column with percentage difference in range 1.9% to 18.3%. Most of HySC and CFHS column specimens failed due to local buckling at the top and middle section of the column caused by concrete crushing. The columns failed due to global buckling after prolong compression load. After the compression load was lengthened, the columns were found to fail due to global buckling except for HySC02.

• 한국환경농학회지
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• 제37권3호
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• pp.197-206
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• 2018

BACKGROUND: The present study aimed to examine the crops capable of growing and adapting to the external environment and various stresses of reclaimed agriculture land for the development of high value-added agricultural utilization technology based on reclaimed land through standardization and empirical study of cultivation environment for cultivating crops. METHODS AND RESULTS: Two crops namely turnips and beets were selected for the salt tolerance test of soil environmental conditions on reclaimed land. Turnip and beet seedlings were planted on the soil collected at the 'Seokmun' reclaimed land. There are five treatments such as non-treatment, 1.0, 2.0 (control), 4.0 and $8.0dS{\cdot}m^{-1}$ of EC. The contents of betacyanin in beet roots was highest in control and decreased with increasing salt concentration. The GSL contents in the turnip roots waswere highest at EC 2.0 and decreased with increasing salt concentration, whereas those in turnip leaves waswere high both in the non-treated control and atthe EC 1.0-treatment. But, tThere was, however, no statistical differences among the treatments. CONCLUSION: The degree of salt tolerance of crops was examined, and the limit EC iswas expected to be $3.0{\sim}4.0dS{\cdot}m^{-1}$ as reported to date. If the soil improvement is performed and irrigation systems are used in the actual reclaimed land, the EC of supplied irrigation will be low, and desalination effecttreatment by the lower EC of the supplied irrigation on the soil will lead to more favorable soil condition of the rhizosphere and cultivation environment offor the crops than those in the port experiment. Therefore, monitoring the salinity, water content and ground water level will enable prediction of the rhizosphere environment, and setting up irrigation management and supplying irrigation will lead to crop cultivation results that are close to normal.

• Korean Journal of Acupuncture
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• 제36권1호
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• pp.63-73
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• 2019

Objectives : This study was designed to investigate the effects of Alismatis Rhizoma (AR) pharmacopuncture at BL23 on acute renal failure induced by cisplatin. Methods : The Sprague-Dawley rats were divided into Normal group (no injection of cisplatin and no treatment), Control group (cisplatin injection without treatment), Acu group (needling at BL23 after cisplatin injection), AR-PA1 group (treated with $0.3571mg/kg/20{\mu}l$ of AR pharmacopuncture at BL23 after cisplatin injection), and AR-PA2 group (treated with $1.7855mg/kg/20{\mu}l$ of AR pharmacopuncture at BL23 after cisplatin injection). Each treatment was given once daily for 8 days. Changes in body weight, kidney weight, tumor necrosis factor-alpha ($TNF-{\alpha}$), interleukin-6 (IL-6), Cu-Zn superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GPx), serum blood urea nitrogen (serum BUN), and serum creatinine were observed. Results : Body weight was significantly increased in AR-PA1 on $4^{th}$ and $6^{th}$ days and AR-PA2 on $2^{nd}$ day. $TNF-{\alpha}$ was significantly decreased in Acu, AR-PA1 and AR-PA2 groups. Cu-Zn SOD was significantly increased in AR-PA2 group. GPx was significantly increased in AR-PA1 and AR-PA2 groups. But kidney weight, IL-6, serum BUN and serum creatinine were not significantly changed in any groups compared to control group. Conclusions : In acute renal failure induced by cisplatin, AR pharmacopuncture has a mitigating effect on the inflammatory reaction related to the increase of $TNF-{\alpha}$ in the kidney tissue and a protective effect on the oxidative stress of the kidney tissue. However it is unlikely to restore the glomerular function or inhibit the renal swelling.

• Journal of the Korean Wood Science and Technology
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• 제31권5호
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• pp.72-79
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• 2003

신뢰성 설계에서 재료강도의 분포 특성은 기본적인 입력 변수로 사용된다. 따라서 강도특성의 분포형태 및 그에 따른 인자들을 정확하게 결정하는 것은 신뢰성 설계를 위한 필수적인 작업이다. 지금까지 강도성능 평가는 주로 무결점 소시편에 대한 실험결과가 사용되어 왔다. 그러나 이러한 방법은 부재가 실재 사용되는 조건을 제대로 반영하지 못함에 따른 오차를 포함하게 된다. 본 연구에서는 구조재로 많이 사용되는 2×6부재(38 mm×140 mm, 길이 3.0 m) 498본에 대하여 육안검사를 통해 등급을 구분하고, 휨시험을 실시하였다. 신뢰성 설계로 전환을 위해 각 등급의 강도특성에 대한 분포형태 및 인자를 결정하였다. 분포형태의 결정을 위해 정규분포, 대수정규분포, 웨이블분포의 세가지 분포형태에 대한 square error를 비교하고, KS test를 통하여 결정된 분포형태의 적합성을 확인하였다. 모든 등급에서 휨강도(MOR)의 가장 적합한 분포형태는 웨이블분포로 나타났으며, 휨탄성계수의 경우는 정규분포가 가장 적합한 것으로 나타났다.

• 대한본초학회지
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• 제33권6호
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• pp.19-28
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• 2018

Objectives : The objective of this study was to investigate the protective effect of Flaxseed oil and Chrysanthemi Indici Flos 50% ethanol extract in an HCl/ethanol induced acute gastritis model. Methods : ICR mice were divided into 6 groups; normal mice (Nor), gastritic mice with distilled water (Veh), gastritic mice with 10 mg/kg sucralfate (SC), gastritic mice with 16 g/㎏ Flaxseed oil (FO), gastritic mice with FO + 50 mg/kg Chrysanthemi Indici Flos (FCL), and gastritic mice with FO + 100 mg/kg Chrysanthemi Indici Flos (FCH). Then, mice were orally administered with 150 mM HCl/60% ethanol and caused acute gastritis. After 1 hr, mice were sacrificed, and blood and stomach tissue were collected. Results : Administration of FCL and FCH to mice prior to the induction of gastritis was found to reduce gastric injury. reactive oxygen species (ROS) and peroxy nitrite ($ONOO^-$) levels of stomach tissues were significantly decreased in FO, FCL, and FCH compared to Veh group. As results of stomach protein analyses, FCL and FCH effectively reduce inflammatory-related factors such as inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and interleukin 1 beta ($IL-1{\beta}$) in gastric lesion mice. In addition, nuclear factor kappa B p65 ($NF-{\kappa}B$ p65) and phosphorylation inhibitor of nuclear factor kappa $B{\alpha}(p-I{\kappa}B{\alpha})$ were down-regulated in FCL and FCH administrated gastric lesion mice. Conclusions : These results suggest that FCL and FCH has an inhibitory effect against gastric injury. Therefore, FCL and FCH has the potential to be used as a natural therapeutic drug.

• 대한본초학회지
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• 제33권1호
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• pp.37-46
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• 2018

Objectives : Liver disease is an inflammatory reaction caused by oxidative stress, viral, alcohol, and drug properties. Inflammatory reaction causes hepatitis and chronic hepatitis is persistent, it progresses to liver fibrogenesis and liver cancer. The aim of this study was to confirm the hepatoprotective effect of Tongyuhwalhyeol-tang(Tongqiaohuoxue Decoction) (TH) and Gamtongyuhawlhyeol-tang(GTH) in TAA-induced liver injury animal model. Methods : The antioxidant activities were evaluated through in vitro experiments, such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) radical scavenging assays, total polyphenol and total flavonoid content measurement. To confirm the liver protective effect, induced by Thioacetamide (TAA) for 3 days injection at 200 mg/kg rats. TH and GTH were treated 3 days at 200 mg/kg/day. The changes of reactive oxygen species (ROS), peroxynitrite ($ONOO^-$), alanine aminotransferanse (ALT) and aspartate aminotransferase (AST) in serum were analyzed after experiment. Also, expression of anti-inflammation, anti-oxidant related proteins were investigated by western blot analysis. Results : TH was inhibited the antioxidant activities. In the TAA-induced rat, TH decreased ROS, $ONOO^-$, ALT, AST level in serum. Inflammation related protein expressions increased in TAA-induced rat compared to normal rat. However, TH group inhibited the down expression of these proteins. Also, anti-oxidant related protein expressions increased in TH group compared TAA-induced rat. Conclusion : Therefor, these results suggested that TH provided hepatoprotective effects on the hepatic injury leading to the reduction of inflammatory response. In addition, the effect of TH was superior to that of GTH.

• 터널과지하공간
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• 제33권1호
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• pp.42-56
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• 2023

고준위방사성폐기물의 심층처분시스템에서 천연방벽은 처분시설을 물리적으로 지지함과 동시에 방사성 핵종의 이동을 지연시키는 역할을 최소 수십만년 이상 수행해야 한다. 천연방벽의 지구조적 장기진화평가를 위해서는 암반 절리의 장기거동 분석이 필수적이며, 여기에는 마찰회복 거동이 포함된다. 본 연구에서는 암반 절리의 수리-역학적 조건 하 마찰회복 거동을 슬라이드-홀드-슬라이드(slide-hold-slide, SHS) 실험을 통해 실험적으로 분석해 보고자 하였으며, 이를 위해 서로 다른 거칠기의 절리 시험편을 대상으로 역학적 및 수리-역학적 조건에서 SHS 실험을 수행하였다. 수리-역학적 조건에서 마찰회복률은 더 증가하는 경향을 보였으며, 이는 거칠기가 큰 시험편에서 더 분명하게 나타났다. 또한, 절리면에 작용하는 유효 수직응력이 작은 경우에 수리-역학적 조건의 영향이 더 크게 작용함을 확인할 수 있었다. 이러한 결과들은 천연방벽 암반 절리의 마찰회복 거동을 파악하는 데 유용한 기초자료로 활용될 수 있을 것으로 기대된다.