• 대한한의학방제학회지
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• 제6권1호
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• pp.157-173
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• 1998

The following study looked at the effects of Hyangsayukgunjatang and Hyangsayukgunjatang-ga-kyenegum, moryobun on gastric ulcers in rats. In the 1st experiment, ulcers were induced by method of shay's pylorus-ligated in rats. Subjects were administered 2 kinds of medicine, Hyangsayukgunjatang and Hyangsayukgunjatang-ga-kyenegum, moryobun, which were taken orally. The quantity of gastric juice secretion, total acidity of gastric juice, HCI secretion and serumgastrin content were measured and tissues of gastric mucosa epithelium were observed. 1. The quantity of gastric juice secretion in Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treated groups showed significant decrease incomparision with the control group. 2. In relation to total acidity of gastric juice, only Hyangsayukgunjatang -treated groupshowed significant decrease in comparison with the control group. 3. HCI secretion of Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treated groups showed significant decrease in comparision with the control group. 4. Content of serum gastrin, which were present in Hyangsayukgunjatang -treated and Hyangsayukgunjatang-ga-kyenegum, moryobun- treated groups showed significant decrease in comparision with the control group. 5. The degree of ulcer occurrence & parietal cell numbers and chief cell numbers of Hyangsayukgunjatang-treated and Hyangsayukgunjatang-ga-kyenegum, moryobun-treatedgroups, which were observed by macrographic & histologic method showed signicant decreasein comparison with the control group. Hyangsayukguniatang-treated group prooved to be increasingly effective. From above the experiment results it can be concluded that Hyangsayukgunjatang will be more clinical effective on curing gastric ulcers induced by method of Shay's pylorus-ligated rather than that of Hyangsayukgunjatang-ga-kyenegum, moryobun.

• 대한지구과학교육학회지
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• 제4권1호
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• pp.32-42
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• 2011

The purpose of this study is to provide meaningful basic materials for organizing a science curriculum in future by analyzing the status and changes of contents about astronomical phenomena in textbooks according to the changes of the science curriculum of elementary school. A main target of analysis is science textbooks of elementary school in curriculums from 1st to 7th. For the analysis, the analytic frame based on contents in astronomy textbooks of teachers colleges and colleges of education was used. The result of the analysis is as in the following. First, astronomy accounted for average about 7% of all pages of textbooks in all of science curriculums. The 1st educational curriculum had the most learning quantity of 10.40%, and the 6th curriculum had the least quantity of 4.39%. These results show that astronomy was not a small part and was considered important in each science curriculum of elementary school considering that earth science accounted for 17-26% of all pages in elementary school science curriculum. Second, the things that have been dealt with in common in all science curriculums from 1st to 7th of elementary school are the shape of the earth, the rotation and the revolution of the earth, the occurrence of the seasons, the apparent motion of the sun, the status and motion of the moon, the movement of a star, the brightness and distance of a star, constellations, the sun, planets and others. These contents are expected to be dealt with continuously as basic contents to organize astronomy regardless of the changes of curriculum. Third, in science curriculum of elementary school, astronomical phenomena based on life experiences regarding the earth, the moon and the sun are mainly dealt with in the first and the second grade. Contents requiring principles-understanding and research are dealt with in the fifth and sixth grade. These results show that elementary school science curriculum dealing with astronomy reflects the developmental stages of students and considers principle of learning possibility.

• 한국콘텐츠학회논문지
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• 제9권1호
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• pp.62-72
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• 2009

본 논문에서는 청주시의 음식물류폐기물 처리시스템에 무선주파수인식(RFID:Radio Frequency Identification)태그를 적용하는 것을 제안한다. 청주시에서 운영하던 기존의 시스템은 월정액제로서 배출량이 다름에도 같은 수수료를 지불해야하는 형평성의 문제가 발생하게 된다. 또한 음식물류폐기물의 정확한 규모의 발생과 처리에 관한 현황 파악이 불가능하여 폐기물의 처리를 효율적으로 관리하지 못하게 되어 정책 결정에 반영하기 어렵다. 반면에 RFID 태그를 이용하여 음식물류폐기물의 처리를 종량제로 실시하면 자동으로 자료의 관리 및 분석을 할 수 있고 수거, 운반, 처리로 이어지는 음식물류폐기물의 흐름 및 감독에 매우 용이하다. 또한 태그의 복제 및 도용이 불가능하다. 이러한 시스템을 통하여 결과적으로 음식물류폐기물의 감소를 가져올 수 있고 경제적 효과와 친환경적인 폐기물의 처리를 실행할 수 있다. 더 나아가서 현재 정부에서 추구하고 있는 RFID/USN을 통한 u-city 건설에도 기여할 수 있다.

• 한국멀티미디어학회논문지
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• 제9권7호
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• pp.801-807
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• 2006

본 연구는 국악기 피리의 소리합성을 위한 기초 단계로, 피리의 음색 특징을 분석하였다 분석은 세 가지로 나누어 첫째, 피리의 음색 특징을 스펙트럼 분석을 통하여 오보에와 비교하였고, 둘째, 피리 소리들의 어택(attack)부분의 시간대별 분석을 통하여 소리 발생과정에 따른 음색을 분석하였으며, 마지막으로 악기연주의 중요한 역할을 하는 비브라토의 특성을 분석해 보았다. 그 결과 피리 음색은 서양악기와 달리 높은 배음들의 음량이 높게 나타났고, 소리발생 초기단계(어택 부분)에서는 노이즈 양이 급격히 줄어드는 것과 반하여 배음들의 음량 값이 높아졌으며, 비브라토에서도 음량위주로 변화하는 서양악기와 달리 음고와 음량이 동시에 변화한다는 특성을 알 수 있었다. 이러한 배음에 따른 음색 특징과 소리 발생과정에서의 음색변화, 그리고 비브라토에서의 음고와 음량 변화는 피리의 독특한 음색을 잘 나타내 주는 특징들로써 소리합성에 있어서 반드시 적용되어져야 할 것이다.

• 대한환경공학회지
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• 제31권5호
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• pp.325-331
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• 2009

본 연구는 팔당호내 조류의 발생특성 파악을 위해 수행되었다. 2006-2008년 매주 측정한 자료를 토대로 클로로필-a 농도는 봄철에 가장 높은 것으로 조사되어 여름철에 가장 높게 조사되었던 2000년 이전 자료와 다른 결과를 나타내었다. 월간 측정 자료에 의하면 2008년 총 조류개체수도 봄철에 높게 나타났다. 전체적으로 규조류가 우점하였으며 연평균값으로는 총 조류개체수의 87%를 차지하였으며, 특히 봄과 겨울에 우점정도가 높았다. 하절기의 경우 특정시기에 남조류가 우점을 차지하였다. 조류에서 기인하는 냄새 유발물질인 2-MIB와 geosmin은 2008년 7월에 특히 높게 나타났는데 조류와 냄새물질 발생간의 상관관계에 대한 보다 많은 연구가 필요하다.

• 한국방재학회 논문집
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• 제8권3호
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• pp.123-128
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• 2008

본 연구는 소양호 상류유역의 자운천 유역을 대상으로 2005년 1개년동안 유량과 탁도를 조사하여, 월별로 강우특성에 따른 하천의 탁도가 변화하는 양상을 고찰하였다. 고찰결과, 5월$\sim$8월에 강우강도 및 강우지속시간에 의하여 높은 탁도가 발생되는 것을 알 수 있었으며, 반면 9월 이후에는 강우의 초기 세척효과로 인하여 탁도가 낮게 지속적으로 발생되는 것을 확인하였다. 다음으로 탁도에 대한 지배인자의 영향력을 살펴보았으며, 5월, 6월에는 지배인자중 강우강도가 89%, 7월, 8월에는 강우강도가 67%, 강우지속시간이 32%로 탁도 발생에 유의적인 영향을 미치고 있는 것을 확인하였다. 또한 탁도 발생에 영향력 있는 지배인자에 대하여 회귀분석을 실시하여 회귀식을 제안하였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권5호
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• pp.213-221
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• 2002

In order to improve the reliability of XLPE cables, it is necessary to find the useful diagnostic parameter according to long term aging. This paper described the change of partial discharge(PD) phase Properties of XLPE cable insulation with branch type electrical tree degradation. for long term aging. To understand the PD Properties with $\phi$ -q-n distributed shape of XLPE insulation, specimens were prepared by 22.9㎸ distribution cable and made in a type of block(16${\times}$16${\times}$3[mm]). Ogura needles having tip radius of l0${\mu}{\textrm}{m}$ were inserted into each block pieces. The measuring system was consisted of PD detector, digitizer for digital conversion, VXI system for signal processing. The PD properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed. We analyzed the relationship between electrical properties(PD Quantity, PD initiation angle, PD extinction angle, PD occurrence angle : (PD extinction angle - PD initiation angle)) and the normalized aging rate. We found PD parameter, PD initiation angle and occurrence angle, which are a useful diagnostic parameter in estimating the branch type electrical tree for XLPE insulation condition.

• International Journal of Automotive Technology
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• 제8권2호
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• pp.137-147
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• 2007

Homogenous Charge Compression Ignition (HCCI) combustion systems can be broadly divided for the process applied to 4-stroke and 2-stroke engines. The former process is often referred to as simply HCCI combustion and the latter process as Active Thermo-Atmosphere Combustion (ATAC). The region of stable engine operation tends to differ greatly between the two processes. In this study, it was shown that the HCCI combustion process of a 4-stroke engine, characterized by the occurrence of autoignition under a high compression ratio, a lean mixture and wide open throttle operation, could be simulated by operating a 2-stroke engine at a higher compression ratio. On that basis, a comparison was made of the combustion characteristics of high-compression-ratio HCCI combustion and ATAC, characterized as autoignited combustion in the presence of a large quantity of residual gas at a low compression ratio and part throttle. The results showed that one major difference between these two combustion processes was their different degrees of susceptibility to the occurrence of cool flame reactions. Compared with high-compression-ratio HCCI combustion, the ignition timing of ATAC tended not to change in relation to different fuel octane numbers. Furthermore, when internal EGR was applied to high-compression-ratio HCCI combustion, it resulted in combustion characteristics resembling ATAC. Specifically, as the internal EGR rate was increased, the ignition timing showed less change in relation to changes in the octane number and the region of stable engine operation also approached that of ATAC.

• Mycobiology
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• 제45권4호
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• pp.240-254
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• 2017

Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

• 천문학회지
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• 제52권4호
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• pp.133-144
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• 2019

We develop forecast models of daily probabilities of major flares (M- and X-class) based on empirical relationships between photospheric magnetic parameters and daily flaring rates from May 2010 to April 2018. In this study, we consider ten magnetic parameters characterizing size, distribution, and non-potentiality of vector magnetic fields from Solar Dynamics Observatory (SDO)/Helioseismic and Magnetic Imager (HMI) and Geostationary Operational Environmental Satellites (GOES) X-ray flare data. The magnetic parameters are classified into three types: the total unsigned parameters, the total signed parameters, and the mean parameters. We divide the data into two sets chronologically: 70% for training and 30% for testing. The empirical relationships between the parameters and flaring rates are used to predict flare occurrence probabilities for a given magnetic parameter value. Major results of this study are as follows. First, major flare occurrence rates are well correlated with ten parameters having correlation coefficients above 0.85. Second, logarithmic values of flaring rates are well approximated by linear equations. Third, using total unsigned and signed parameters achieved better performance for predicting flares than the mean parameters in terms of verification measures of probabilistic and converted binary forecasts. We conclude that the total quantity of non-potentiality of magnetic fields is crucial for flare forecasting among the magnetic parameters considered in this study. When this model is applied for operational use, it can be used using the data of 21:00 TAI with a slight underestimation of 2-6.3%.