• Herbal Formula Science
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• v.6 no.1
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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.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.1
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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.

• The Journal of the Korea Contents Association
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• v.9 no.1
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• pp.62-72
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• 2009

In this paper, we propose an application of RFID(Radio Frequency Identification) tag to food wastes disposal system of Cheongju city. The existing system of Cheongju city is monthly fixed amount levy system. The weak point of this system must pay a same commission in spite of each other different food wastes quantity. Also the accurate occurrence quantity of the food wastes and present condition grasp of control are impossible. It will not be able to reflect to a policy decision because does not manage the control of the food waste efficiently. On the other hand, when a food wastes measuring system using RFID is executed tag, it will manage and analyze automatically the obtained data. And collecting, transporting and handling of the food wastes come to be very easy. Also the reproduction and embezzlement of the tag are impossible. As a result of this system, it brings the decrement of the food waste. Therefore the economic effect could be come true and the food wastes is controlled environment-friendly. The food wastes disposal system using RFID tag will be able to contribute in u-city constructions with RFID/USN technology which pursues from the government.

• Journal of Korea Multimedia Society
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• v.9 no.7
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• pp.801-807
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• 2006

This study analyzed the timbral characteristics of Pliri by basis step for the sound synthesis for Piri, Korean traditional musical Instrument. By analyzing this material, we can find out three characteristics about the study of the spectrum analysis for the sound synthesis of Piri. First, compared the timbral characteristics of Piri with Oboe through the spectrum analysis, Second, analyzed the timbral characteristics by the sound occurrence process through the time zone analysis of the attack part of the sound started. Finally, analyzed the special characteristics of the vibrato that is important role of musical instrument performance. As a result, the timbral characteristics of Piri is that the volume of the high harmonics was appeared to be high unlike the general classical instrument and the noise quantity rapidly decreased in the sound attack part but the volume value of harmonics increased. And also vibrato that is performance technique is changed pitch and amplitude at the same time by contrast with the general classical instrument. Thus, the timbral characteristic of Piri by the harmonics and the timbre change by the attack part which is sound occurrence process and the change of the pitch and amplitude in the vibrato is characteristic that represented unique quality of Piri. We expect that this achievement can be applied to sound synthesis.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.325-331
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• 2009

This study was performed to evaluate characteristics of algal occurrence in Lake Paldang. Chlorophyll a concentration was highest during spring, based on weekly measurements from 2006 to 2008, which revealed a different trend compared to the data before 2000 that showed the highest level during summer. Total algae cell quantity was also highest during spring, based on monthly data. Overall, Bacillariophyceae was dominant and represented 87% of total algae cells and occupation was more significant during spring and winter. Cyanophyceae was dominant during summer. 2-MIB and geosmin originating in algae which caused odor problems was high in July 2008, and more research on the relationship between algae and production of odor causing material is needed.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.123-128
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• 2008

This study inquired into changes of turbidity of a river depending on the rainfall characteristics of each month through investigating the water quantity and turbidity of Jawoonchun drainage basin in the upper reaches of Soyangho (lake) for the year of 2005. It could be seen from the study that high turbidity occurred during the period from May to August due to rainfall intensity and rainfall duration. On the other hand, it could be confirmed that turbidity was constantly low after September because of early cleansing effect of rainfall. Next, the influence of controlling factors of turbidity was looked into. For May and June, it was 89% rainfall intensity among the controlling factors, for July and August, it was 67% rainfall intensity and 32% rainfall duration that was confirmed to have influence over the occurrence of turbidity. In addition, regression analysis was carried out about the controlling factors that had influence over the occurrence of turbidity and regression equation was suggested.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.5
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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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• v.8 no.2
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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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• v.45 no.4
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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.

• Journal of The Korean Astronomical Society
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• v.52 no.4
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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%.