• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.37-41
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• 1997

스프링클러 소화설비는 화재가 발생하였을 때 자동적으로 감열, 작동하여 초기화재 진압을 목적으로 하는 소화설비로서 소화특성은 화재발생으로부터 소화가 시작되는 화재감지특성과 화재제어 및 진압에 대한 방사특성1) 으로 FRS2) 3)와 FMRC4)에서는 열응답의 민감도를 나타내는 반응시간지수(RTI)의 측정방법과 이론을 제시하였다. 반응시간지수는 스프링클러헤드의 작동에 필요한 충분한 열을 주위로부터 얼마나 빠른 시간내에 흡수 할 수 있는지를 나타내는 특성치로서 가열공기의 온도 및 속도에 의해 결정되며 값이 적을수록 헤드가 조기에 작동하게 된다. (중략)

• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.353-354
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• 2017

본 연구는 2016년 1월부터 대구 경북에 소재하고 있는 저작기능장애가 있는 환자를 대상으로 구강건강행동지수와 치면세균막지수를 비교하였다. 연구결과 연구대상자들의 일반적인 특성과 교육 전 구강건강행동지수는 집단 간 유의한 차이가 없었다. 구강근기능훈련 프로그램 진행 후 QHI를 비교한 결과 진행후 통계적으로 유의하게 낮아지는 것으로 나타났다.

• The Journal of the Korea Contents Association
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• v.10 no.11
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• pp.209-216
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• 2010

The purpose of this study was analyzing the first permanent molars condition that was how catch on general oral health of the children in primary school, to make use of the basic data on dental health policy project for the school oral health. The sampling was done at the primary school in Suncheon. It made a survey on the first permanent molars of 823 person who had attended in March, 2009. By using the WHO standards and Clune's dental health capacity, the conditions of first permanent molars calculated. DMFT index and it's condition of first molars statistically are analyzed by Pearson's correlation. 1. The dental health capacity of the first permanent molars was 92.2%. 2. The DMFS index of first permanent molars was 3.97. 3. The dental health capacity of first permanent molars have related with DMFT index(r= -0.895). 4. DMFS index of the first molars have positive relation with DMFT index(r= 0.902). In this repory, I would like to suggest that the evaluation of dental health project for the school aged children should be considered including the healthy status of the first molars.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.39-44
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• 2012

For the purpose of examining the dental biofilm reduction effect and control difficulty level through a dental biofilm control program in this study, the total of 131 medical records (82.9%) were used for the final analysis upon excluding the records that were not suitable for this study among the records of 158 persons for the medical records of clinical hygiene case reports that were submitted from 2006 to 2011 by students at the Department of Dental Hygiene at N University located in Chungnam region. The result of examining the dental biofilm reduction effect according to the visit number when conducting a dental biofilm control program showed that the dental biofilm index reduced meaningfully as the visit number increased. However, in the case of those that visited for 7 sessions, the level of reduction was not statistically meaningful. For the purpose of comparing the dental biofilm index mean per area of teeth during the final session visit of dental biofilm control program, the area of teeth was classified into labial/buccal surface, lingual/palatal surface and proximal surface, and the dental biofilm index of lingual/palatal surface was the highest with 26.5%. The result of measuring the dental biofilm of maxilla/mandible revealed meaningful differences between the dental biofilm index of maxilla and mandible. The result of analyzing the dental biofilm index of labial/buccal surface, lingual/palatal surface and proximal surface revealed meaingful differences among the dental biofilm index of labial/ buccal surface, lingual/palatal surface and proximal surface.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.467-476
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• 2013

Site index information given from forest site map only exist in the sampled locations. In this study, site index for unsampled locations were estimated using kriging interpolation method which can interpolate values between point samples to generate a continuous surface. Site index of Pinus densiplora in Danyang area were calculated using Chapman-Richards model by plot unit. Then site index for unsampled locations were interpolated by theoretical variogram models and ordinary kriging. Also in order to assess parameter selection, cross-validation was performed by calculating mean error (ME), average standard error (ASE) and root mean square error (RMSE). In result, gaussian model was excluded because of the biggest relative nugget (37.40%). Then spherical model (16.80%) and exponential model (8.77%) were selected. Site index estimates of Pinus densiplora throughout the entire area in Danyang showed 4.39~19.53 based on exponential model, and 4.54~19.23 based on spherical model. By cross-validation, RMSE had almost no difference. But ME and ASE from spherical model were slightly lower than exponential model. Therefore site index prediction map from spherical model were finally selected. Average site index from site prediction map was 10.78. It can be expected that regional variance can be considered by site index prediction map in order to estimate forest biomass which has big spatial variance and eventually it is helpful to improve an accuracy of forest carbon estimation.

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.3
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• pp.234-241
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• 2011

This paper proposes a simple static overmodulation strategy that extends the linearity of the inverter output voltage. The proposed method obtains the reference vector having the instantaneous value directly from the modulation index based on the magnitude of fundamental voltage, and has a simplified form of phase command. This method does not need trigonometric functions for calculating the magnitude of the reference vector. The magnitude of reference voltage and holding angle in the overmodulation region corresponding to the modulation index are determined in advance to have the same fundamental voltage magnitude by using the result of Fourier series expansion.

• Journal of Korean society of Dental Hygiene
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• v.17 no.5
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• pp.931-942
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• 2017

Objectives: The purpose of this study was to provide a counseling program basis for the department satisfaction in dental hygiene department according to the subjective factors of happiness in dental hygiene students. Methods: A self-reported questionnaire was completed by 197 dental hygiene students in Gwangju from April 10 to 30, 2017. From collected data, general characteristics, happiness index and department satisfaction of the subjects were investigated. Data were analyzed using the IBM SPSS 18.0 program. Results: The happiness index according to general characteristics showed a significant difference in grade, character, friendship, academic achievement, pocket money satisfaction and health condition. The department satisfaction according to general characteristics showed a significant difference in grade, age, character, motivation for further study, friendship, academic achievement, pocket money satisfaction, health condition, sleep time. Happiness index showed a significant correlation with department satisfaction. The happiness index was higher as the department satisfaction was higher. Factors that affect happiness index are friendship, health condition, relationship satisfaction, perception satisfaction, school satisfaction, curriculum satisfaction and department satisfaction. Conclusions: The happiness index was higher as the department satisfaction was higher. Therefore, it is necessary to develop various programs to increase the happiness.

• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.160-165
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• 1997

The objective of this study was to analyze dominance-diversity of Quercus mongolica community which characterize the boreal-temperate deciduous forest in Korea. Employing the releve method of Muller-Domboes and Ellenberg, 100 quadrats were sampled in the natural forest of Mt. Odae, Mt. Chumbong and Mt. Jungwang in Kangwon-do, where Quercus mongolica community is in the situation of climax or subclimax. On the basis of Braun-Blanquet method, field survey, which accounts ffor the characters of the species structure of Quercus mongolica community, was carried out between 1991 and 1994. Quercus mongolica community was relatively in a stable condition because of the even distribution of its various indices: the species diversity index was 0.4~1.2; the species richness index was 2~11; the evenness index was 0.6~0.9. The dominance-diversity curve were comparatively of lognormal distrivution with a gentle slope in all communities. The species sewuence curve for Quercus mongolica - Lindera obtusiloba community had relatively a steep slope, which meant that the evenness of the community would be low. The species sequence curve for Quercus mongolica - Carpinus cordata community had a slow slope, which meant that the evenness and the stability of the community would be high.

• Journal of Korea Water Resources Association
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• v.31 no.6
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• pp.657-665
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• 1998

New diagnosing method o flood possibility was proposed. The method can be processed by following steps: first, decide if current available water resources are above normal or not; second, compute a consecutive period above normal; third, precipitation is accumulate through the period; fourth, daily depletion (runoff and evapotranspiration) amount is subtracted from the accumulated precipitation and remains are translated to one day's precipitation, which is called effective precipitation; and finally, effective precipitation index. the larger effective precipitation index means the higher flood possibility. This method has been applied to the flood event occurred in the central region of Korea at late July 1996 and compared with the study by Korea Water resources Association (1996). The new method is proven to be much faster in computation, and therefore much better in practical use for emergency situation than current rainfall-runoff models. It is because the new method simplifies some steps of currently used method such as parameter estimation and water level observation. It is also known that new method is more scientific than any other methods that use accumulated precipitation only as it considers the runoff depletion in time

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1025-1034
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• 1993

We have measured ${\pi}^*$, $\alpha$ and $\beta$ polarity parameters of 2-propanol / hexane and ethyl acetate / hexane mixed solvents over the entire range of composition. For the ethyl acetate / hexane system, only ${\pi}^*$ and $\beta$ were measured since $\alpha$ of these mixed solvents are defined zero. We have corrected the measured polarity parameters to obtain consistent data with the existing literature data assuming a good linear correlation between the measured and the true values. The variation patterns are consistent with the expected trends based on the chemistry of the solvent components. The general trends of the two solvent systems are summarized as follows. ${\pi}^*$ merely increases as the content of the more polar solvent increases while $\alpha$ and $\beta$ increase with the increase of the content of the more polar solvent, then decrease upon continuing addition of the more polar solvent.