• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.942-945
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• 2006

The picture quality of a plasma display panel is very sensitive to the phosphor characteristics such as luminescence, decay time, surface properties, and even longevity of phosphor material in itself. In our previous work, the discharging characteristics in green cell of PDP were demonstrated to be enhanced by coating $Zn_2SiO_4:Mn^{2+}$ phosphors with positively charged metal oxide such as MgO. Here, $Zn_2SiO_4:Mn^{2+}$ phosphors were coated by various metal oxides for examining the coating effect on the picture quality. Specially, longevity while fabricating the panel was investigated for panel application in this work. Also the effects of ion and electron bombardment on the phosphor surface will be discussed in this work.

• 생약학회지
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• 제36권2호통권141호
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• pp.65-69
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• 2005

The extract contents of various Phellinus species (Hymenochaetaceae) including P. linteus, P. baumii, P. pini and P. igniarius of domestic and foreign products, were examined to standardize the quality of these products. The differences of various extract contents were identified and compared between different species of Phellinus products. The thin layer chromatographic patterns were also analyzed and six unidentified samples were thought to originate from P. baumii and P. igniarius. The chemical standardization for the quality control of various origins could be suggested by this study.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1081-1081
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• 2001

The constant need for quality improvement and production rationalization in the chemical and related industries has led to the increasing replacement of conservative control procedures by more specific and environmentally compatible analytical techniques. In this respect, vibrational spectroscopy has developed over the last yews - in combination with new instrumental accessories and statistical evaluation procedures - to one of the most important analytical tools for industrial chemical quality control and process monitoring in a wide field of applications. In the present communication this potential is demonstrated in order to further support the implementation of mid-infrared (MIR), near-infrared (NIR) and Raman spectroscopy Primarily as industrial on-line tools. To this end the data of selected feasibility studies will be discussed in terms of the individual strengths of the different techniques for the respective application.

• 환경위생공학
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• 제13권3호
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• pp.128-132
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• 1998

In this study, water quality characteristics of lakes in the Seosan area are analyzed. Components water quality were analysed at 10 sampled points in each lakes, and the results were evaluated for seasonal variation. It was found that water quality was over II~III class. Most of lakes in the Seosan area which implies that are suitable as the maintenance water. The concenturation of T-N, T-P was observed IV~V class during all seasons. Particularly, T-N concenturation peaks in spring, while was lowered in other seasons. In the lake, high concenturation of T-N, T-P bring about Eutrophication when algae was growth causing various physico-chemical changes in the water. It is suggested that the water quality management strategies need to be applied for each lake.

• 한국항만학회지
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• 제12권2호
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• pp.313-322
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• 1998

The distributions of chemical oxygen demand (COD) and suspended solid (SS) in Ulsan Bay were simulated and reproduced by a numerical ecosystem model for the practical application to the management of marine water quality and the prediction of water quality change due to coastal developments or the constructions of breakwater and marine facilities. Comparing the computed with the observed data of COD and SS in Ulsan bay the results of simulation were found to be good enough to satisfy the practical applications.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.16-25
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• 2013

The Korean groundwater law regulates 20 groundwater contamination parameters, including 14 specific harmful substances. Expanding the number of groundwater quality standards are needed to cope with recent groundwater quality deterioration due to the use of various chemicals. Chemical ranking and scoring system (CRS) is a scientific tool to sort priority chemicals by considering exposure and toxicity potentials. In this study, we developed a CRS for scoring and ranking of possible groundwater pollutants and screened priority substances to be later considered in the Korean standard expansion. Chemical Ranking Of groundWater pollutaNts (CROWN) incorporates important parameters consisting of exposure potential, human and water ecotoxicity, interests, and certainty. Furthermore, CROWN additionally evaluated existence of other media standards to consider impacts by contamination of other media. The 197 substances that were common to 9 countries were selected first. CROWN evaluated and ranked each chemical, and finally suggested priority substances. Suggested priority substances were classified into two groups according to the groundwater use purposes: drinking and non-drinking. The priority substances were further classified into $1^{st}$ and $2^{nd}$ group priorities. The $1^{st}$ group consists of 75 substances, including the all the Korean groundwater standard parameters. CROWN will be used in selecting groundwater pollutants for possible inclusion in the Korean standard expansion.

• 분석과학
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• 제25권2호
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• pp.102-113
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• 2012

현행 환경오염공정시험기준 중 먹는 물 수질공정시험기준과 실내공기질 공정시험기준에 대해 국제규격에 부합화된 KS ISO규격과의 일원화에 관해 연구하였다. KS규격 23,000여종을 대상으로 먹는 물 및 실내공기질관련 KS 규격을 조사하였다. 환경분야관련 KS규격은 KS I로 분류되며, 총 653종으로 조사되었으며, 이중 국제규격에 부합화된 KS I 규격은 583종으로 조사되었다. 먹는 물 수질공정 시험기준은 총 100개 기준을 대상으로 ISO/TC 147 "Water Quality" 관련 KS 규격 총 232종을 비교 검토하였으며, 실내공기질 공정시험기준은 "ISO/TC 146 "Air Quality" 관련 KS 규격 총 95종 규격을 비교 검토하였다. 문헌검토와 비교시험을 통해 먹는 물 및 실내공기질 공정시험기준과 일원화 가능한 국제규격에 부합화된 KS규격 연구결과 먹는물수질공정시험 100개 기준 중 사전일원화 완료 23개 기준, 일원화 가능 29개 기준, 일원화 불가 12개 기준, 대응 규격 없는 기준이 36개로 평가되었으며, 실내공기질 공정시험기준 17개 기준 중 사전일원화 완료 1개 기준, 일원화 가능 3개 기준, 일원화 불가 3개 기준, 대응규격 없는 기준이 10개 기준으로 평가되었다.

• 한국대기환경학회지
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• 제24권3호
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• pp.284-299
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• 2008

Emission input modules was developed to produce emission input data and change some profiles for Sparse Matrix Operator Kernel Emissions (SMOKE) using Clean Air Policy Support System (CAPSS)'s activities and previous studies. Specially, this study was focused to improve chemical speciation and temporal allocation profiles of SMOKE. At first, SCC cord mapping was done. 579 SCC cords of CAPSS were matched with EPA's one. Temporal allocation profiles were changed using CAPSS monthly activities. And Chemical speciation profiles were substituted using Kang et al. (2000) and Lee et al. (2005) studies and Kim et al. (2005) study. Simulation in Seoul Metropolitan Area (Seoul, Incheon, Gyeonggi) using MM5, SMOKE and CMAQ modeling system was done for effect analysis of changed input modules of SMOKE. Emission model results adjusted with new input modules were slightly changed as compared to using EPA's default modules. SMOKE outputs shows that aldehyde emissions were decreased 4.78% after changing chemical profiles, increased 0.85% after implementing new temporal profiles. Toluene emissions were decreased 18.56% by changing chemical speciation profiles, increased 0.67% by replacing temporal profiles as well. Simulated results of air quality were also slightly elevated by using new input modules. Continuous accumulation of domestic data and studies to develop input system for air quality modeling would produce more improved results of air quality prediction.

• 한국토양비료학회지
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• 제47권6호
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• pp.558-562
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• 2014

Cover cropping and liquid manure application are considered as effective ways to replace the use of chemical fertilizer in orchard. This study was conducted to investigate the effect of cover crop species and liquid manure application rate on green manure production, leaf mineral content, fruit quality and soil chemical properties in pear orchard. The treatments include rye and hairy vetch as cover crops, two liquid manure application levels based on N and $K_2O$ requirement on each cover crop species, and chemical fertilizer as control. Green manure production was higher in hairy vetch than in rye. K content of pear leaves and soil exchangeable K content increased in N based liquid manure application treatments. The yield was higher in rye + liquid manure and fertilizer treatments, and fruit quality was not different between the treatments. Taking all of these into account, rye + $K_2O$ requirement-based liquid manure application is recommended in pear orchard for not only sufficient nutrient supply but also prevention of any problem related with soil $K_2O$ accumulation in pear orchard in long-term perspective.

• 한국환경과학회지
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• 제9권5호
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• pp.429-436
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• 2000

In order to study on the variational characteristics of water quality and chlorolphyll a concentration the water samples were collected daily or three times a week during the period from April 1990 to November 1991 at Kukdong port located in the northern Kamak bay of Southern Korea I made an analysis on biological factor as chlorophyll a concentration as well as physico-chemical factors such as water temperature salinity sigma-t dissolved oxygen, nutrients (ammonia, nitrite, nitrate, phosphate, and silicate) N/P ratio and chemical oxygen demand. In Northern Kamak bay seasonal variations in physical factors such as water temperature salinity and sigma-t were very marked. On the other hand chemical factors such as nutrients concentration and COD were not so. Chemical factors, in particular silicate were influenced by input of freshwater. And the roles of silicate on the seasonal succession of phytoplankton species composition was very low. Phytoplankton biomass as measured by chlorophyll a concentration was very high all the year round and it was controlled by the combination of several factors especially of N/P ratio determined by dissolved inorganic nitrogen.