• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.283-296
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• 2008

The numerical simulations for groundwater flow were carried out to support the input parameters for safety assessment in LILW repository site. As the input parameters for safety assessment, the groundwater flux into the underground facilities during construction, flow rate through the disposal silo after closure of disposal silo and flow pathway from the disposal silo to discharge area were analyzed using the 10 cases groundwater flow simulations. From the total 10 numerical simulation results, the statistics of estimated output were similar to among 10 cases. In some cases, the analyzed input parameters were strongly governed by locally existed high permeable fracture zone at radioactive waste disposed depth. Indeed, numerical simulation for well scenario as a human intrusion scenario was carried out using the hydraulically severe case model. Using the results of well scenario, the input parameters for safety assessment were also obtained through the numerical simulation.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.138-143
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• 2020

Black chokeberry (Aronia melanocarpa) has been suggested to exert antioxidant and anti-inflammatory effects due to its high polyphenol content. However, the mechanisms underlying the effects of black chokeberry on the alterations of nuclear factor E2-related factor 2 (NRF2) and nuclear factor κB (NF-κB) in macrophages have not been thoroughly studied. In this study, we investigated the protective effects of polyphenol-rich black chokeberry extract (CBE) against lipopolysaccharide (LPS)-induced oxidative stress and inflammation in RAW 264.7 macrophages. CBE significantly attenuated the increase of cellular reactive oxygen species (ROS) levels and the nuclear translocation of NRF-2 in LPS-stimulated macrophages. The mRNA abundances of Nrf2 and its downstream antioxidant genes were significantly decreased in LPS-stimulated macrophages. The LPS-induced mRNA expression of proinflammatory cytokines was significantly inhibited by reducing the nuclear translocation of NF-κB by CBE. These data suggest that black chokeberry may be used for the prevention of oxidative stress and inflammation-associated disease.

• Journal of Korean Society of Forest Science
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• v.75 no.1
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• pp.1-18
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• 1986

This study was initiated to estimate productivity of Quercus variabilis stand. However the practical objective of this study was to provide some information to establish the basis of selecting the suitable site for Quercus variabilis. The productivity measured in terms of DBH, height, basal area and stem volume was hypothesized, respectively, to be a function of a group of factors. This study considered 32 factors, 20 of which were related to the forest environmental factors such as tree age, latitude, percent slope, etc. and the rest of which were related to soil factors such as soil moisture, total nitrogen, available $P_2O_5$, etc. The data on 4 productivity measurements of Quercus variabilis growth and related factors cited were collected from 99 sample plots in Kyeongbook and chungbook provinces. Some factors considered were, in nature, discrete variables and the others continuous variables. Each kind of factor was classified into 3 or 4 categories and total numbers of such categories were eventually amounted to 110. Then each category was treated as an independent variable. This is amounted to saying that individual variable was treated a dummy variable and assigned a value 1 or 0. However the first category of each factor was deleted from the normal equation for statistical consideration. First of all, each of 4 productivity measurements of Quercus variabilis growth was regressed and, at the same time, those 110 categories. Secondly, the partial correlation coefficients were measured between each pair of 4 productivity measurements and 32 individual foctors. Finally, the relative scores were estimated in order to derive the category ranges. The result of these statistical analyses could be summarized as follows: 1) Growth measurement in terms of height seems to be a more significant criterion for estimation of productivity of Quercus variabilis. 2) Productivity of forest on stocked land may better be estimated in terms of forest environmental factors, on the other hand, that of unstocked land may be estimated in terms of physio-chemical factors of soil. 3) The factors that a strongly positive relation to all growth factors of tree are age group, effective soil, soil moisture, etc. This implies that these factors might effectively be used for criteria for selecting the suitable site for Quercus variabilis. 4) Parent rock, latitude, total nitrogen, age group, effective soil depth, soil moisture, organic matter, etc., had more significant category range for tree growth. Therefore, the suitable site for Quercus variabilis may be selected, based on this information. In conclusion, the above results obtained by the multivariable analysis can be not only the important criteria for estimating the growth of Quercus variabilis but also the useful guidance for selecting the suitable sites and performing the rational of Quercus variabilis forest.

• Journal of the Korea Society for Simulation
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• v.24 no.3
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• pp.61-68
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• 2015

Mobile ad hoc networks (MANETs) are self-organized dynamic networks populated by mobile nodes. This paper presents the improved cross-layer approach to complement the recent works for video transmission services on MANET. We use a statistical design of experiment and analysis in order to investigate interactions between major factors of each layer effectively with minimizing ns-3 simulation run time. The proposed cross-layer approach considers MANET protocol layers (i.e., physical, network and transmission layers) and an application layer (i.e., a video encoder) as factors simultaneously. In addition, the approach defines an objective video quality metric as a response variable. The result of this paper can be applicable as a preliminary research to design an optimized video transmission application which has ability to adjust controllable factors to dynamic uncontrollable factors.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.3
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• pp.104-109
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• 1981

The experiment was designed to measure splash erosion and to investigate the relationships between soil detachment, kinetic energy and C factor at various soils and crops under the natural rainfall, using the modified Ellison cup. The results obtained were as follows: 1. Splash erosion increased as the texture was coarser, reaching a maximum amount in loamy sand of 12.6ton/10a/year, 9.7ton for loam, 9.0ton for sandy loam, and 7.0ton for clay loam. 2. Splash erosion positively related to kinetic energy ($EI_{30}$) but negatively to K value. 3. A considerable relationship between splash erosion and kinetic energy was observed under coverage less than 50%; however, it decreased with increasing canopy resulting in no relation over 90% coverage. The amount of soil detachment by natural rainfall ranged from 10 to 15ton/10a at various cropping systems. 4. The particle size distribution of splashed soil was similar to that of original one and fine sand($250-100{\mu}$) marked the highest detachment and splash.

• The Journal of the Korea Contents Association
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• v.19 no.3
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• pp.520-529
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• 2019

This study is intended to provide basic data for health management of firefighters in the future by empirically looking into health hazard factors of firefighters in Busan City. It was revealed that firstly, the danger of harmful chemicals in a fire was perceived the most by firefighters, who extinguish a fire in person on the scene of a fire, and it was followed by the danger of falling while putting out a fire. This study is intended to provide basic data for health management of firefighters in the future by empirically looking into health hazard factors of firefighters in Busan City. It was revealed that firstly, the danger of harmful chemicals in a fire was perceived the most by firefighters, who extinguish a fire in person on the scene of a fire, and it was followed by the danger of falling while putting out a fire. Moreover, the danger of shift work was perceived the most by paramedics. This corresponds to the existing studies arguing that shift work is harmful to health. Next, the overload of patient transport was recognized as the second biggest hazard factor. This demonstrates they are worried about various second accidents that may happen due to a lot of patient transport works. In addition, the possibility of causing a traffic accident was perceived as a hazard factor too, since they must drive ambulance cars quickly to transport patients. Lastly, rescue workers regarded these hazard factors to be most dangerous. This is associated with their occupational characteristics, because rescue workers are the closest to diverse risks including a fire.

• 월간산업보건
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• s.182
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• pp.21-30
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• 2003

본 분석기법은 유해인자별 작업환경측정 및 특수건강진단 시료를 분석할 때 간편하게 활용할수 있는 방법으로 산업보건관련 유관기관에 실질적인 도움을 주고자 합니다. 이 분석기법들 중에는 공식적으로 검증, 채택되지 아니한 기법이 있음을 알립니다.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.04a
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• pp.44-45
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• 1996

역삼투막을 통한 물질전달에 대해서는 많은 모델식이 제안되어 왔으며, 이들을 통해 막의 특성을 규정하여 왔다. 역삼투막을 통한 물질전달에는 많은 변수가 있으며, 이들 가운데 일부는 정량적으로 측정할 수 없는 부분이 포함되어 있으며, 기존의 방법은 이들을 실험을 통해 정해지는 막이나 공정에 의존하는 특성값으로 고려하였다. 본 연구논문은 이와 같은 막특성값으로 간주되어온 분배계수의 고찰을 토대로 막분리 과정에서 일어나는 물질전달현상을 막물질의 특성과 연계하여 설명하고 이로부터 막분리에 유리한 막물질형태의 제안을 목적으로 하고 있다.

• Electronics and Telecommunications Trends
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• v.25 no.6
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• pp.11-19
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• 2010

LBS 기술은 현재까지 이동통신 기술의 발전 및 측위 기술의 고도화를 통해 다양한 측위 인프라를 기반으로 발전되어 왔다. 측위 환경 및 방식에 따른 다양한 LBS 솔루션이 공존하며 대부분의 표준 단체에서 새로운 기술을 개발하고 있다. 네트워크 기반 측위 기술은 쉽게 접근할 수 있는 인프라임에도 불구하고 상용 수준에서 만족할 만한 성능을 보이고 있지 않다. 따라서 본 논문에서는 네트워크 기반 측위의 중요성 및 범용성을 감안하여 관련 기술 및 표준화 동향을 살펴보고 현재의 기술 수준을 향상시키고 고정밀 위치인자를 가능하게 하기 위해서 해결되어야 할 과제에 대해 고찰해 보도록 한다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.59-60
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• 1999

20세기 후반 소비문화의 확산과 더불어 자동차 문화가 보편화되면서 전세계적으로 고농도 오존이 문제되고 있다. 1940년대 LA 지역에서 광화학 오염현상이 처음 발견된 이래 1970, 80년대 본격적으로 연구 투자가 이루어지는 동안 LA 지역의 이상적 기후와 오존 농도 변화는 광화학 오염의 전형이었다. 그러나 1990년대 들어, 지역규모의 오염물질 이동에 따른 광역 오염 (미국 동부), 종관풍이 약할 때 오염물질이 정체되며 발생하는 국지 오염 (유럽), 산성비 연구 과정에서 밝혀지기 시작한 강우와 구름의 영향들이 알려지며 오존 오염은 당초에 생각하였던 것보다 훨씬 복합적인 문제임을 인식하게 되었다.(중략)