• 한국멀티미디어학회논문지
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• 제24권8호
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• pp.1138-1148
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• 2021

In this study, we developed a 'shared-use mobility'-mounted local particulate matter monitoring terminal technology to measure the actual particulate matter concentration around me. As a mobile terminal device in the form of an IoT sensor platform, it is designed to be separated into a control module and a sensor module to minimize interference between sensors and to consider the optimal observation position of each sensor. As a result of the field test, it was confirmed that particulate matter was locally different depending on time and space even within the same area. In addition, it was confirmed that the concentration of particulate matter in the relevant section differed by up to 100 times compared to the surrounding area due to specific sources of particulate matter such as unpaved roads. In addition, we positively reviewed the applicability of the service in the real-time metaverse environment using this result. Through technological advancement and application of multiple shared-use mobilities, we expect to be able to provide new services for practical smart city air environment monitoring, such as localized particulate matter information, air pollution event information, and identification of causes of particulate matter.

• 한국융합학회논문지
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• 제11권11호
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• pp.393-403
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• 2020

본 연구는 청소년을 대상으로 미세먼지에 대한 지식, 태도 및 행위의 수준을 파악하고 미세먼지 행위에 영향을 미치는 요인을 검증하여 미세먼지 대응에 효과적으로 대처하기 위한 전략 개발의 기초자료로 활용하고자 수행되었다. 서술적 조사연구이며, 연구 대상은 D시 일개 고등학교 학생 218명이었으며, 연구 기간은 2019년 5월이며 2주간 실시되었다. 수집된 자료는 SPSS WIN 18.0 프로그램을 사용하여 t-test, one-way ANOVA, Pearson's correlation coefficient, multiple regression을 분석하였다. 미세먼지 태도(β=0.52, p<.001)가 미세먼지 행위에 유의한 영향을 나타내었으며, 설명력은 31%이었다(F=15.19, p<.001). 미세먼지 교육 경험(β=0.08, p=.157), 부의 학력(β=0.08, p=.288), 모의 학력(β=0.05, p=.463), 미세먼지 지식(β=-0.05, p=.415), 동거 가족(β=-0.09, p=.126), 학교 성적(β=-0.02, p=.710)은 미세먼지 행위에 유의한 영향을 미치지 않았다. 청소년을 위한 미세먼지 행위를 높이기 위한 프로그램 개발 시 미세먼지 태도를 증진시키기 위한 방안 마련이 필요하다.

• Journal of the Optical Society of Korea
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• 제1권2호
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• pp.104-109
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• 1997

The propagation properties of three-dimensional dark spatial solitons having odd ring formation is analyzed numerically in the frame of the (1 + 2)-dimensional nonlinear Schrodinger equation and compared with a pair of odd dark solitons. We discuss the experimental excitation condition of an odd ring dark soliton, which is superimposed on a finite-width background beam, with phase masks.

• 상하수도학회지
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• 제18권6호
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• pp.807-813
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• 2004

Wastewater was treated by two different treatment processes; activated sludge process and advanced wastewater treatment process (KNR process) using lab-scale experiment. Two treated wastewater showed good treatment efficiency of organic matter removal, up to 90% removal. Nitrogen and phosphorus were not effectively removed though activated sludge process, while KNR process showed good removal efficiency of nitrogen and phosphorus; 56% nitrogen removal and 95% phosphorus removal. KNR process showed better removal efficiency of organic matter, nitrogen, and phosphorus compared to activated sludge process. Organic matter characterization was tracked though measurement of UV scan, SUVA, and XAD fractionation. Treated wastewater showed higher SUVA value than wastewater influent, indicting less aromatic characteristic of organic matter. XAD fractionation showed hydrophilic fraction decreased though wastewater treatment, suggesting microbes preferentially digest hydrophilic and aliphatic molecules rather than hydrophobic and aromatic molecules of organic matter.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.201-202
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• 2023

Now, there are many cases where materials are maintained at construction sites or standard construction prices are not in accordance with the applicable regulations, resulting in a lot of fine dust. Therefore, a particulate matter measurement system is applied not only to manage particulate matter at construction sites but also to reduce particulate matter .This study aims to evaluate the applicability of this particulate matter measurement system to the construction site through long-term measurement experiments using a light scattering method particulate matter measurement instrument at the construction site.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.267.1-267.1
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• 2008

• 대한화학회지
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• 제66권6호
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• pp.493-508
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• 2022

화학은 물질의 성질, 변화, 구조에 대해 다루는 교과로, 관찰 가능한 성질과 변화를 미시적인 수준으로 설명하고, 이를 이론과 법칙 등으로 설명하는 체계를 갖는다. 국가수준 교육과정에서는 물질의 성질과 변화에 대해 초등학교부터 고등학교에 이르기까지 연속적으로 다루면서, 학생들이 물질에 대한 이해를 심화시킬 수 있도록 내용을 구성하고 있다. 즉, 물질의 성질과 변화에 대한 이해는 화학의 관점에서 우리 주변을 설명하기 위한 기반이 되며, 이 둘은 2015 개정 과학과 교육과정에서 화학 교과의 영역으로 분류된다. 본 연구에서는 국가수준 학업성취도 평가의 결과를 분석하여 중학생들의 물질의 성질과 물질의 변화 영역에 대한 이해를 확인하고자 하였다. 이러한 목적에서 본 연구에서는 2015년부터 2019년까지 출제된 물질의 성질에 대한 12개 문항, 물질의 변화에 대한 19개 문항을 분석하였다. 핵심 개념에 따라 문항들을 분류하여 분석한 결과에 따르면, 두 영역에 대한 이해는 보통학력과 기초학력에 해당하는 학생들에게서 큰 폭으로 변화하고 있었다. 입자의 관점을 사용하고 과학 개념과 모형을 연관시켜 현상을 설명하거나, 이 두 영역에서 다루는 탐구에 대해 이해하는 것이 성취수준에 따라 차이가 있었다. 이러한 분석을 토대로 물질의 성질과 물질의 변화 영역에 대해 교수학습 과정에서 개선이 필요한 사항들을 논의하였다.

• 천문학회지
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• 제30권1호
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• pp.95-106
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• 1997

We investigate the velocity distribution of dark matter in the disk of a galaxy like the Milky Way at the solar radius. Using N-body simulations with the total mass and z-component of angular momentum conserved, we calculate the response of a dissipationless dark matter galactic halo during the dissipational collapse of the baryonic matter in spiral galaxy formation. The initial distribution of dark matter and baryonic particles is assumed to be a homogeneous mixture based on a King model. The baryonic matter is assumed to contract, forming the final luminous components of the galaxy, namely the disk and, in some cases, a bulge and central point. Both slow and fast growth of the luminous components are considered. We find that the velocity distribution of dark matter particles in a reference frame rotating slowly about the galaxy center in the plane of the disk is similar to a Maxwellian, but it is somewhat boxier, being flatter at the peak and truncated in the tails of the distribution. We tabulate parameters for the best-fitting Maxwellian and modified-Maxwellian distributions. There is no significant difference between slow collapse and fast collapse for all these results. We were unable to detect any effect of disk formation on the z-dependence of the dark matter density distribution.

• Fisheries and Aquatic Sciences
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• 제6권4호
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• pp.194-202
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• 2003

Budgets for water, nitrogen, and chemical oxygen demand (COD) were determined in two 0.012 ha earthy-bottom ponds stocked with Israeli strain common carp at an initial stocking density of $20\;fish/m^3$. Total ammonia nitrogen (TAN) concentrations increased continuously but later decreased in pond A as a consequence of high nitrification. COD concentrations increased during the experimental period due to the accumulation of feed input. Nutrient budgets showed that feed represented $94-95\%$ of nitrogen input and about 99% of organic matter input. Fish harvest accounted for $40\%$ of nitrogen and organic matter input. Seepage and water exchange removed $15-17\%$ of nitrogen input but only $1-2\%$ of organic matter. Draining of the ponds removed $20-26\%$ of input nitrogen, mostly in inorganic forms, but removed only minus organic matter. Fish and water column respiration accounted for $39\%$ of organic matter input, and benthic respiration accounted for $7-12\%$ of organic matter input. No significant change of nitrogen and organic matter in both pond bottoms were found during the three-month growth period. The unrecovered input nitrogen, about $6.3-13\%$, was lost through denitrification and ammonia volatilization. On a dry matter basis, fish growth removed $31\%$ of total feed input and left $69\%$ as metabolic wastes.

• 한국작물학회지
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• 제44권1호
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• pp.44-48
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• 1999

Uptake, assimilation and translocation of nitrogen and dry matter assimilation and translocation in ten rice cultivars were observed in no-till direct-sown rice-vetch cropping system. There was a large degree of variation in N-uptake, grain yield, nitrogen translocation efficiency and dry matter assimilation and translocation in tested rice cultivars. Forty kg N/ha base, as compound fertilizer (21-17-21% of N-P-K) three weeks after sowing and 30 kg N/ha top-dressed at panicle initiation stage as in the form of (NH$_4$)$_2$$CO_2$ was applied. ‘Newbounet’, ‘Daesanbyeo’, and ‘Hwayeongbyeo’ showed higher translocation efficiency. The contribution of pre-heading dry matter assimilates to grain ranged from 33% to 99% of dry grain weight. Dry matter of ‘Calrose 76’ was lower than Newbounet but N content was higher in Calrose 76 than Newbonnet. By maturity, N content in vegetative parts declined considerably more than dry matter, vegetative and reproductive parts, N translocation efficiency, and N harvest index. Nitrogen translocation efficiency was greater in ‘Nonganbyeo’, Daesanbyeo, and Newbounet. Grain N concentration was positively correlated with N concentration or N content of the vegetative parts at heading in Nonganbyeo, ‘Dasanbyeo’, ‘Dongjinbyeo’, and Newbonnet. These results indicated that the greater amount of dry matter and N accumulated before heading stage, the higher translocation rates of dry matter to grain and the greater net losses at maturity.