• Journal of Life Science
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• v.25 no.3
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• pp.336-344
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• 2015

The capacity for liver regeneration involves a variety of nutritional factors. Vitamin C has multiple metabolic and antioxidant functions. In this study, we investigated the role of vitamin C in liver regeneration following hepatectomy in senescence marker protein (SMP)-30 knockout (KO) mice. Partial hepatectomy was performed by resecting the median and left lateral lobes of mice. Vitamin C accelerated liver recovery in SMP30 KO mice treated with vitamin C (KV). The livers of the KV mice exhibited lower levels of aspartate aminotransferase and lower injury than those of the KO mice. Increased type II transforming growth factor-β receptor (TGF-βRII)-mediated regeneration signaling was accompanied by HGF and cMet in the KV but not the KO mice. Consistent with this, the expression of cell cycle regulatory proteins, including cyclin D1 and proliferating cell nuclear antigen (PCNA), increased rapidly in the KV mice. Enhanced activation of ERK and GSK-3β proteins and a significantly increased number of binuclear hepatocytes were also detected in the livers of the KV mice. Moreover, the KV mice synthesized the highest levels of albumin. These data suggest that treating SMP30 knockout mice with vitamin C resulted in earlier recovery and liver regeneration by activation of the regeneration system.

• Journal of Korean Society of Forest Science
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• v.36 no.1
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• pp.33-37
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• 1977

The secular trends and seasonal variation of the prices of imported lauan sawtimber, domestic red pine logs and sawtimber have been analyzed to find out the features and origins of price fluctuation in Korea for the period of 1961~1971. The results may be summarized as follows: 1. The relative prices of red pine logs were raised by 1.23 percent per year, and those of red pine and lauan sawtimber were decreased by 0.10 and 0.93 percent, respectively through the period. As a whole, there is a tendency in the country that timber prices were gradually decreased by lowing timber demand through savings in consumption and exploitation of alternative materials, with the increased supply through continuous log import. 2. There is also a tendency that the seasonal variation reduced in the last 15 years. In the period of 1961~1968, the seasonal price indices were peaked in spring and autumn, but thereafter peaked in spring and dropped down until winter. 3. In secular and seasonal variations of timber prices, the trend of sawtimber prices was dependent upon that of log prices but the fluctuation was larger in log prices.

• THE INDUSTRY AND TECHNOLOGY OF GAS
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• v.2 no.1
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• pp.6-21
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• 1998

에너지는 인류문명발달의 원동력이며 현대 산업사회에서는 모든 산업활동과 국민경제에 필수적인 요소이므로 세계 거의 모든 나라들은 에너지의 안정확보를 국가정책의 제 1로 삼고 있다. 세계적으로 볼 때 시대의 변천에 따라 에너지의 주역도 바뀌어 산업혁명 후 제2차 세계 대전까지는 석탄이 주역이었고, 2차대전 후 1970년대 석유위기 전까지는 석유가 단연 주역이었다가 석유위기 후 1980년대는 천연가스와 원자력이 상당부문 석유를 대체하고 있으며, 21세기에는 가스이용기술의 개발에 따라 편리성과 경제성에서 가스의 우월성으로 타에너지를 대체하고, 특히 지구온난화방지 노력과 관련하여 전세계적인 $CO_2$ 감축 목표에 따라 청정연료로서 타에너지 보다 사용이 크게 늘어 2010년까지는 1995년의 $50\%$가 증가하여 21세기 연료의 주역이 될 것으로 전망된다. 우리나라는 에너지의 $98\%$를 외국에서 도입하는 상황에서 석유의존도가 $60\%$를 넘고 있으며, 원자력발전소의 확장에 어려움이 많고 세계기후변화협약을 비준한 국가로서 지구온난화방지를 위한 의무를 지게 될 것이므로, 에너지 공급원의 다원화를 통한 안정확보와 청정에너지 이용의 확대 및 에너지 산업에 대한 규제완화 등으로 경제성에 입각한 시장경쟁에서 가스는 우위를 확보함으로써 1차 에너지중 가스의 비중이 매우 높아질 것으로 전망되고있다. 따라서 가스산업은 우리나라 에너지산업중 가장 크게 발전하고 또 다른 에너지가 여러면에서 제약을 받게 될 때 이러한 제약을 극복하는 대체에너지로서 역할이 크게 전망되며, 특히 발전, 열병합, 냉방, 자동차 연료부문에서의 사용이 크게 늘어날 것으로 예상되어 이러한 가스이용의 확대에 대비하여 가스자원의 개발, 국내 공급설비의 확충, 연구개발등에 대한 투자와 규제완화에 의한 시장경쟁에 대한 대비가 필요하다.계산모델 및 원자력병원에서 보유하고 있는 방사선 치료계획장치인 CAP-PLAN의 선량계산모델의 계산 결과와 비교하여, 흡수선량은 ${\pm}10\%$ 이내에서 거리로는 0.4mm 이내에서 대부분 일치하였다. 최대 오차는 각각 $11.3\%$ 및 0.8mm로 나타났다. 이상의 결과들로부터 새로 개발한 금으로 된 기구와 Ir-192 seed를 이용한 근접 방사선 치료법으로 안구의 악성종양에 대한 치료를 보다 효과적으로 시행할 수 있을 것으로 기대된다. 구성원을 간소 목적을 위하여 사용할 수 있어야 하겠다 마지막으로 이들 내의 위험 집단을 우선적으로 파악. 접근하여야 할 것이다. 위험 집단으로는 경제적 문제로 적절한 의료 이용을 할 수 없는 저소득층, 문화적으로 열등한 위치에 있는 여성층과 초기 이민 적응에 가장 문제를 일으킬 소지가 있는 노년층을 들 수 있겠다. 이 연구는 몇 가지 제한점을 가진다. 첫째. 연구 대상자 선정이 어려워서 자원자를 대상으로 연구가 행해졌다. 둘째. 적은 수의 연구 대상자를 대상으로 연구가 행해졌다. 셋째. 연구기간이 짧았던 까닭에 좀더 상세한 사례 연구가 이루어질 수 없었다 좀 더 신뢰할 수 있는 표본 추출 방법을 통하여 선정된, 많은 연구 대상자를 가지고, 심도 있는 연구가 추후 반복적으로 이루어져야 할 것이다.더욱 더 발전을 거듭하고 있으며, 외식은 여행과 여가 활동의 필수적인 요소로써 그 역할을 일조하고 있다. 이와 같은 여가시간의 증가는 독신자들에게는 좀더 많은 여유시간을 가족을 이루고 있는 가족구성원들에게는 가족과의 유대를 강화하는 휴식과 오락의 소비 트렌드를 창출시켰다. 이와 더불어 외식은 식사를 해결하기 위한 단순한 수단에서 벗어나 동기와 동반자에 따라 달라지는 행동 패턴을 나타내고 있으며, 연령과 목적에 따라 세분화되는 분명한 선호도를 나타낸다. 지난 10여 년간 외국으로부터 수입된 다양한

• Journal of Life Science
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• v.12 no.3
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• pp.349-356
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• 2002

In order to observe the bioactivity of ovariectomized rats, nonovariertoized (sham) group, ovariectomized (Ovx) group, ovariectomized ginseng total saponin (GTS)-treated (Ovx+ GTS) group and ovariectomized ginseng water extract (GW)-treated (Ovx+CW) group were made. We measured AST (L-aspartate aminotransferase) and ALT (L-alanin aminotransferase) in sera, and MDA (malondialdehyde:lipid peroxidation), SOD (superoxide dismutase), catalase, total-glutathione (GSH + GSSG) and GPx (glutathione peroxidase) in liver tissue total homogenates of rat. AST activity of serum in Ovx group was 2.11 times increased, but ALT activity was not changed compared to Sham group. In AST activity, they tend to decrease significantly in each substance such as GTS and GW administered group. Lipidperoxides of each fraction in Ovx group were highly increased compared to Sham group. Extracts of ginseng-treated group markedly inhibited lipid peroxidation by 62% ∼72%. And as the result of the measurements of SOD, catalase, total-glutathione and GPx which are antioxidant enzyme, antioxidant enzymes in Ovx group much lower than in Sham group. But they were significantly increased in each substance such as GTS and GW, administered group. Based on the results, it is supposed that more produced free radicals decreased antioxidant enzyme. And it is also thought that extracts of ginseng can inhibit aging by reducing antioxidant enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.815-820
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• 2004

The effect of capsaicin (0.02%) on the concentrations of liver and serum lipids, GOT and GPT activities, and hepatocyte morphology in male Sprague Dawley rats fed diets with or without erotic acid (1.0%) for 28 days was studied. Liver triglyceride concentration was increased by approximately 4.7-fold after erotic acid-feeding, wherease simultaneous feeding of capsaicin and erotic acid reduced its concentration by 38%. Orotic acidfeeding elevated liver cholesterol concentration, but an addition of capsaicin to the erotic acid diet resulted in the significant decrease in liver cholesterol. Capsaicin alone did not affect the liver triglyceride and cholesterol concentrations. Reduction of the serum concentrations of triglyceride and cholesterol by capsaicin was also observed in rats fed diets with erotic acid. The serum GOT and GPT activities were not significantly different among the experimental groups. Liver tissue morphology showed that the hepatocytes of erotic acid-feeding rats were a typical fatty liver with numerous fat droplets, whereas simultaneous feeding of capsaicin with erotic acid reduced the size and numbers of fat droplets. The present study demonstrated that the diet containing 0.02% capsaicin can prevent the erotic acid-induced fatty liver.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.139-148
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• 2019

Fostering science-gifted individuals are very important for the future of the nation, and it is especially important to cultivate information-gifted individuals in the age of the fourth industry. There is no standardized curriculum for each gifted education center of the University. Therefore, in this study, we analyzed how effective the curriculum developed on the basis of computing thinking is to affect the characteristics of the information-gifted individuals. The curriculum developed on the components of computing thinking was applied to the information-gifted students of K University. In order to verify the effectiveness of the curriculum, we developed a creative personality test and an intrinsic motivation test, and conducted tests before and after the training. We compared pre-post test results by t-test with R program. The creative personality test consisted of 36 items with 6 factors: risk-taking, self - acceptance, curiosity, humor, dominance, and autonomy. The intrinsic motivation test consisted of 20 items with 5 items: curiosity and interest oriented tendency, challenging learning task preference orientation, independent judgment dependency propensity, independent mastery propensity, and internal criterion propensity. The effect of the curriculum on the creative personality of the experimental group was significant (0.009, 0.05). The significance level of the intrinsic motivation was 0.056 and was not significant at the 0.05 level of significance.

• Journal of Digital Convergence
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• v.16 no.11
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• pp.221-230
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• 2018

Most of researchers and business futurists agree that traditional organizational designs are inadequate for coping with today's turbulent and increasingly networked world. Executives in small firms find that their organizations must tap into an extended network of partners to achieve the scale and power needed to succeed in industries dominated by large, global firms. As they attempt to build lean yet agile businesses, these executives are finding that they no longer rely on gut instinct alone. Neither can they simply copy organizational model that worked in the past. They must understand how organizational design choices influence operational efficiency and flexibility and, even more important, how to best align the organization with the environment and the strategy chosen to quickly and effectively sense and respond to opportunities and threats This research examines the capabilities required to build businesses that can survive and prosper in today's fast-faced and uncertain environment. The insights presented in this research have emerged from over 30 years of work with hundreds of executives and entrepreneurs as they struggled to build businesses that could cope with the demands of a rapidly changing, networked global economy. The insights from this research suggest that IT is an important enabler for developing the best capabilities required for success.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.694-704
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• 2021

To improve the quality of government-funded vocational training, an accreditation system of vocational training providers has been implemented since 2015. The purpose of this study was to suggest improvement measures by analyzing the accreditation system and the perceptions surrounding it. To this end, accreditation systems from European countries, such as Germany and the UK, as well as related domestic systems, were reviewed. Two surveys were administered to 131 appraisers and 370 vocational training providers. The study results showed that changes to the standard and accreditation processes are not needed at this point. In the long term, however, it will be necessary to request that vocational training providers adopt their quality assurance system. In addition, both appraisers and vocational training providers responded that the accreditation system is being established to increase the quality assurance system within vocational training providers. Based on the study results, several implications for improving the accreditation system were suggested as follows: a vocational training enhancement centered on outstanding vocational training providers; an accreditation system simplification for short-term vocational training providers; a stronger monitoring system during the accreditation period; and an operation of outcome-based accreditation.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.639-649
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• 2011

The purpose of this study aimed to analyze factors on motives to tree burial and choice conditions to tree burial site in order to suggest policy direction for the desirable settlement of tree burial. For those purpose, this study performed questionnaire, targeting 522 visitors of funeral hall all around Korea. As the result, the factors of motives to tree burial were extracted as follows: funeral ceremony progressed along with trees, simplicity, memorial site's easy insurance, environmental friendliness and consideration toward descendants. The factors on choice conditions to tree burial sites were extracted as follows: beauty of natural scenery, emotional mood as a memorial site, convenience, stability and economic feasibility. Based on the results of factor analysis, this study suggested policies related to motives to tree burial as follows: develop various types of tree burial sites, develop a funeral ceremony suitable for tree burial, come into wide use of tree burial as a social welfare service, develop tree burial methods capable of many burials, and improve professionalism to manage tree burial system. In addition, this study proposed related choice conditions to tree burial sites as follows: establish natural forest scenery, convert existing graveyards into tree burial sites, select easily accessible places for tree burial sites, form tree burial sites as places for both rest and memory, and reduce using fee of tree burial site.

• Korean Journal of Optics and Photonics
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• v.13 no.4
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• pp.340-346
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• 2002

To understand the characteristics of the passively Q-switched Nd:YAG laser output energy with $Cr^{4+}$:YAG saturable absorbers, the transmissions of $Cr^{4+}$:YAG and the inversion population densities of Nd:YAG at the onset of Q-switch were experimentally analysed. The measured transmissions at the onset of Q-switch were 0.70$\pm$0.02 and 0.62$\pm$0.02 for the 0.48 and 0.38 of initial transmission, respectively. It means that the initial transmission loss of $Cr^{4+}$:YAG absorber is reduced in a low Q-state due to the initial absorbing effect of $Cr^{4+}$:YAG. In pumping stage, $Cr^{4+}$:YAG has absorbing processes due to the fluorescence and amplified spontaneous emissions of the Nd:YAG even if there is no laser oscillation. The minimum population inversion densities for Qswitch were approximately 3.7${\times}{10^{17}}$ and 4.0${\times}{10^{17}}$ $cm^{-3}$, respectively. At the beginning of Q-switch, the number density of $Cr^{4+}$ions in the ground state of $Cr^{4+}$:YAG was approximately 1.4${\times}{10^{17}}$ $cm^{-3}$ and the ratio of the ground to the excited state of absorbing $Cr^{4+}$ions was 0.44 both. The modified theoretical output energies with the initial absorbing effect were 18 and 18.5 mJ. The measured output energies were 17$\pm$1 and 18$\pm$1.5 mJ, respectively. The quantum extraction efficiencies of Q-switch were 0.32 both. The theoretical Q-switched output results with the initial absorbing effect of the saturable absorber are a good agreement with the experimental results.