• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.704-713
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• 2003

The effect of partial substitution of tungsten for molybdenum on the microstructure and corrosion resistance in 22Cr-5Ni-3Mo duplex stainless steel(DSS) aging heat treated in a temperature range of 600~$1000^{\circ}C$ has been investigated. Electrochemical tests were carried out for the evaluation of corrosion resistance. Aging treatment had hardly influenced the general corrosion resistance. With the increase of aging time, the pitting corrosion resistance of the DSS had decreased, After aging for 2min at 700~$900^{\circ}C$, the pitting potential of the 3Mo steel decreased remarkably, while that of the W-substituted steel hardly changed. During aging. the intermetallic $\sigma$ and secondary austenite ($\gamma_2$) phases were precipitated. and the pitting corrosion and intergranular corrosion resistance were significantly decreased after aging at 700~$750^{\circ}C$ for 10 h, which could be caused by the $\gamma_2$ formation. The ${\gamma}$$_2$ phase could affect the depletion of molybdenum and chromium in the $\gamma_2/\alpha and \gamma_2/\sigma$ boundaries.

• Geomechanics and Engineering
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• 제14권3호
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• pp.241-246
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• 2018

The displacement monitoring data series reconstruction method was developed under equal water level effects based on displacement monitoring data of concrete dams. A dam displacement variation equation was set up under the action of temperature and aging factors by optimized analysis techniques and then the dam displacement hydraulic pressure components can be separated. Through the dynamic adjustment of temperature and aging effect factors, the aging component isolation method of dam displacement was developed. Utilizing the isolated dam displacement aging components, the dam stability model was established. Then, the dam stability criterion was put forward based on convergence and divergence of dam displacement aging components and catastrophe theory. The validity of the proposed method was finally verified combined with the case study.

• Geomechanics and Engineering
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• 제28권1호
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• pp.1-10
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• 2022

In Korea, accidents related to the collapse of deteriorated aging reservoirs occur every year. The grouting method is generally applied to reinforce an aging reservoir. However, when using this method, different reinforcing effects appear depending on the ground conditions. Thus, new construction methods and materials capable of providing consistent reinforcing effects are required. In this study, the direct shear test (DST), model test, and simulation analysis were performed to evaluate the impact of surface stabilizers, generally used to reinforce roads, rivers, and slopes of roads, applied using surface curtain walls on aging reservoirs. The DST results indicate that when the surface stabilizer was mixed with in-situ soil, the increase in cohesion was the highest at a mixing ratio of 9%. No changes in the friction angle were evident; therefore, 9% was determined to be the optimal mixing ratio. In addition, the model test and simulation analysis showed that when 9% of the surface stabilizer was mixed and applied to the aging reservoir, the seepage quantity of water and the saturated area were reduced by approximately 42% and 73%, respectively. Moreover, the comprehensive analysis of results showed that the grouting method could be completely replaced by surface stabilizers applied through surface curtain walls because the technique could secure stability by decreasing the seepage in the aging reservoir.

• 대한한의학원전학회지
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• 제27권2호
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• pp.25-48
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• 2014

Objectives : This study aims to analyze the terms describing anti-aging effects in Dongeuibogam, and to propose the methodology for selecting medicinal herbs related to anti-aging effects. Methods : We considered aging or anti-aging theories by reviewing the major literature in korean medicine or traditional chinese medicine, and then we deduced the concepts describing anti-aging effects and the medicinal herbs for anti-aging effects. We investigated the medicinal herbs based on the terms describing anti-aging effects in Dongeuibogam and drew the methodology for selecting and classifying the medicinal herbs related to anti-aging. Results & Conclusions : The following conclusions could be drawn. 1. A set of causes and signs of aging in Dongeuibogam and a set of therapies for alleviating the aging signs in Chengumikbang, Yanglobongchinseo, and Nolohangeon was found. 2. Anti-aging effects should not be confused with disease treatments. Therefore, we defined the medical terms of anti-aging effects as "the terms expressing the effect of delaying or alleviating the subjective or objective signs of aging concretely". Based upon the terms of anti-aging effects, we defined the medicinal herbs for anti-aging effects as "the medicinal herbs whose effects are described in medical terms expressing the effects of delaying or alleviating the subjective or objective signs of aging concretely". 3. We considered Lycii Fructus, Asparagi Tuber in Dongeuibogam as examples of medicinal herbs whose effects are described in medical terms expressing anti-aging effects. It shows that we can select medicinal herbs for anti-aging effects by comparing the effects of 937 single therapies in Dongeuibogam to the terms describing anti-aging effects defined in this study. Futhermore, the results could be utilized as the basic materials of experimental study on anti-aging.

• 한국콘텐츠학회논문지
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• 제16권7호
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• pp.100-111
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• 2016

본 연구는 노인의 스트레스와 성공적 노화에 있어 낙관성과 가족지지의 매개된 조절효과 검증을 위해 경남지역에 거주하는 65세 이상의 일반노인 584명을 대상을 분석하였다. 분석은 Preacher와 Hayes가 제안한 SPSS Macro방법을 사용하여 경로모형을 통해 연구모형을 검증하였다. 연구모형 검증은 3단계로 실시하였으며, 1단계는 예측변수와 준거변수 관계에서 조절변수가 조절효과를 가지는가를 분석하였고, 2단계는 예측변수와 매개변수의 관계를 확인 후, 3단계에서는 매개된 조절효과를 확인하였다. 분석한 결과를 요약하면 다음과 같다. 첫째, 스트레스와 성공적 노화, 낙관성의 매개효과를 검증한 결과 부분매개모형을 지지하는 것으로 확인되었다. 둘째, 스트레스, 낙관성과 성공적 노화의 가족지지 조절효과를 검증한 결과 조절효과가 모두 있는 것으로 확인되었다. 셋째, 스트레스, 낙관성과 성공적 노화, 가족지지의 매개된 조절효과를 검증한 결과 매개된 조절효과가 있는 것으로 나타났다. 이러한 연구결과를 바탕으로 실천적 함의와 향후 과제를 제시하고, 노년기 성공적 노화를 위한 가족지지 향상방안을 제시하였다.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.241-243
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• 2001

• 한국재료학회지
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• 제26권5호
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• pp.287-291
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• 2016

The effect of heat treatment on the microstructure and mechanical properties of cast Ti-6%Al-4%V alloy was investigated. Heat treatment of cast Ti-6Al-4V alloy was conducted by solution treatment at $950^{\circ}C$ for 30 min; this was followed by water quenching and then aging at $550^{\circ}C$ for 1 to 1440 min. The highest hardness of the heat-treated specimens was obtained by solution treatment and subsequent aging for 5 min due to precipitates of fine ${\alpha}$ that formed from retained ${\beta}$ phase. The tensile strength of this alloy increased without dramatic decrease of the ductility due to microstructural refinement resulting from the decomposition of ${\alpha}^{\prime}$ martensite into fine ${\alpha}$ and ${\beta}$ phases, and also due to the fine ${\alpha}$ phase formed from the retained ${\beta}$ phase by aging treatment for 5 min. In addition, this strengthening might be caused by the transformation induced plasticity (TRIP) effect, which is a strain-induced martensite transformation from the retained ${\beta}$ phase during deformation, and which occurs even after aging treatment at $550^{\circ}C$ for 5 min.

• 대한암한의학회지
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• 제20권1호
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• pp.81-88
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• 2015

Generally, normal cells synthesize adenosine triphosphate (ATP) through oxidative phosphorylation in the mitochondria. However, they produce ATP through lactic acid fermentation on hypoxic condition. Interestingly, many cancer cells rely on aerobic glycolysis for ATP generation instead of mitochondrial oxidative phosphorylation, which is termed as "Warburg effect". According to results from recent researches on differences of cancer cell metabolism from normal cell metabolism and because chemotherapy to suppress rapidly growing cells, as a side effect of cancer treatment, can still target healthy cells, there is merit in the development of small-molecule inhibitors targeting metabolic enzymes such as pyruvate dehydrogenase kinase (PDHK), lactate dehydrogenase (LDH) and monocarboxylate transporter (MCT). For new anticancer therapy, in this review, we show recent advances in study on cancer cell metabolism and molecules targeting metabolic enzymes which are importantly associated with cancer metabolism for cancer therapy. Furthermore, we would also like to emphasize the necessity of development of molecules targeting metabolic enzymes using herbal medicines and their constituents for anticancer drugs.

• 한국연초학회지
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• 제26권1호
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• pp.27-34
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• 2004

This study was carried out to examinate the effect of aging period on chromatic, chemical and organoleptic characteristics, and to evaluate of optimum aging period for each grade in flue-cured leaf tobacco. The leaf tobaccos were produced in 2000, and threshed, redried and packed in carton box under the current methods. Four grades of processed leaf(A3O, B1O, C1L and D3L) were stored during 24 months(May 10, 2001 to April 31, 2003) in warehouse of Chungju Leaf Tobacco Processing Factory. The leaf tobaccos were sampled at three month intervals for analysis of chromatic, chemical and organoleptic properties. Yellow(b), pH values and total sugar contents of four grades were significantly decreased during the aging. Filling values, tar, nicotine and CO contents of tobacco smoke, and puff number of cigarettes were not significantly changed during the aging. Positive correlation coefficients were significantly observed between taste and irritation of the calculated attributes from contents of volatile oil components in leaf tobacco and those of the panel sensory attributes. The ratio of maximum change in taste attribute was larger than that in irritation attribute during aging. The optimum aging periods estimated by taste for A3O, B1O, C1L and D3L were 17.8, 14.9, 10.8, and 9.8 months, respectively. The thin leaf(Primings and Cutters) undergo satisfactory aging earlier as compared to bodied leaf(Leaf and Tips). The results suggest that decrease of aging period for thin leaf from 18～21 to 9～12 months may be beneficial to save storage cost in flue-cured tobacco.

• 한국산학기술학회논문지
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• 제19권6호
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• pp.440-446
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• 2018

본 논문은 고령인력이 조직 혁신에 미치는 효과와 연령 다양성이 이러한 관계를 어떻게 조절하는지를 중심으로 살펴본다. 지식경영 기반 관점에 근거하여, 본 연구는 기업 특유적 지식과 조직 내외부 사회적 연결망 측면에서 고령인력이 일정 정도 조직 혁신에 기여할 수 있을 것으로 보았다. 반면, 고령인력 비중이 지속적으로 늘어나게 되면 새로운 지식 창출관점에서 한계를 가질 수 있으므로 조직 혁신에 미치는 긍정적 효과보다는 부정적 효과가 보다 강하게 나타날 것으로 예상하였다. 이에 더하여, 고령인력과 조직 혁신 간 비선형적 관계를 조절하는 요인으로 연령 다양성의 효과에 대해 살펴보았는데, 본 연구는 새로운 지식의 창출이라는 측면에서 연령 다양성이 고령인력과 조직 혁신 간 비선형 관계를 조절할 것으로 예측하였다. 실증 분석을 실시한 결과, 예측한대로 고령인력과 조직 혁신은 역 U자 관계를 가지고 있었으며, 연령 다양성은 이러한 역 U자 관계를 조절하는 역할을 하는 것으로 나타났다. 이러한 이론적 논의와 실증 결과는 고령인력이 조직 혁신에 미치는 다양한 효과들을 보다 다각적으로 검증하고 이러한 관계에 영향을 줄 수 있는 보다 다양한 요인들에 대한 탐색이 이루어져야 함을 보여준다.