• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.203-212
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• 2005

Anthropogenic emissions of greenhouse gases, particularly carbon dioxide($CO_2$) which arises mainly as wastes from the fossil fuel burning processes, are causing global warming. The effects of global warming become increasingly felt all over the world including sea level rise and extreme weather. The more direct consequences of the elevated atmospheric $CO_2$ on the ocean is the acidification of the surface ocean which brings a far reaching adverse impact on the life at sea and probably on the whole ecosystem of the planet. Improvement in energy efficiency and use of alternative energy sources are being made to reduce $CO_2$ emissions. However, a rapid transition to alternatives seems unachievable within a few decades due to the constraints on the associated technology and socio-economic factors in the world, since fossil fuels make up approximately 85% of the world's commercial energy demands. It has now been recognized that capture and geological sequestration of $CO_2$ could significantly reduce its emissions from fossil fuel utilization and therefore provides the means to rapidly achieve large reductions in $CO_2$ emissions(excerpts from London Convention, LC/SG 28, 2005). In Korea, well-developed sedimentary basins are spread over the vast continental shelf and slope regions, whereas, the land is densely populated and limited in area. Consequently, the offshore area is preferred to the land for the sites for geological sequestration. The utilization of the offshore area, however, may be subject to international agreements including London Convention. In this paper, the recent trends in technologies and regulations for $CO_2$ capture and geological sequestration are described to encourage its applications in Korea.

• Applied Biological Chemistry
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• v.22 no.3
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• pp.166-172
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• 1979

A series of experiments was planned for practical application of rhizobia in grass lands in Korea. This is the report for the studies mainly on the isolation and characterization of alfalfa nodule bacteria, and on the assessment of their nodulation abilities and nitrogen fixation capacities. 1. Total number of 47 strains was isolated from nodules which were taken from alfalfa grown in Daekwanyong, Cheju and other places. 2. Morphological and cultural characteristics of the strains were studied, and attempts. were also made to investigate their antigenic properties and to demonstrate lysogenic strains. The results were; i) the isolates varied in their cultural characteristics on yeast mannitol broth and agar, and in degree of congo red absorption; ii) similarities in their antigenic prorerties were found between the strains: SU 47/M-11, M-13/M-15, and M-3/M-5; iii) no lysogeny was found in the strains. 3. Plant infection test by test tube method in light room were carried out to elucidate the ability of the strains to nodulate Luna alfalfa and of the capacity of such nodules to fix atmospheric nitrogen. The isolates were grouped info non-invasive, ineffective, or effective to the legumes. Those strains which produced effective nodules, supporting similar/higher level of growth as nitrate control were: M-8, 9, 14, 20, 21, 25 and 34.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.21-36
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• 2006

This study was undertaken to analyze the effects of pavement thermal properties and water retention characteristics on the surface temperature of the gray permeable cement concrete pavement during the summer. Following is a summary of major results. 1) The hourly surface temperature of pavement could be well predicted with a heat transfer model program that incorporated the input data of major meteorological variables including solar radiation, atmospheric temperature, dew point, wind velocity, cloudiness and the evaporation rate of the pavements predicted by the time domain reflectometry (TDR) method. 2) When the albedo was changed to 0.5 from an arbitrary starting condition of 0.3, holding other variables constant, the peak surface temperature of the pavement dropped by 11.5%. When heat capacity was changed to $2.5\;kJm^{-3}K^{-1}\;from\;1.5\;kJm^{-3}K^{-1}$, surface temperature dropped by 8.0%. When daily evaporation was changed to 1 mm from 2 mm, temperature dropped by 5.7%. When heat conductivity was changed to $2.5\;Wm^{-1}K^{-1}\;from\;1.5\;Wm^{-1}K^{-1}$, the peak surface temperature of the pavement fell by 1.2%. The peak pavement surface temperature under the arbitrary basic condition was $24.46^{\circ}C$ (12 a.m.). 3) It accordingly became evident that the pavement surface temperature can be most effectively lowered by using materials with a high albedo, a high heat capacity or a high evaporation at the pavement surface. The glare situation, however, is intensified by raising of the albedo, moreover if reflected light is absorbed into surrounding physical masses, it is changed into heat. It accordingly became evident that raising the heat capacity and the evaporative capacity may be the moot acceptable measures to improve the thermal characteristics of the pavement. 4) The sensitivity of the surface temperature to major meteorological variables was as follows. When the daily average temperature changed to $0^{\circ}C\;from\;15^{\circ}C$, holding all other variables constant, the peak surface temperature of the pavement decreased by 56.1 %. When the global solar radiation changed to $200\;Wm^{-2}\;from\;600\;Wm^{-2}$, the temperature of the pavement decreased by 23.4%. When the wind velocity changed to $8\;ms^{-1}\;from\;4\;ms^{-1}$, the temperature decreased by 1.4%. When the cloudiness level changed to 1.0 from 0.5, the peak surface temperature decreased by 0.7%. The peak pavement surface temperature under the arbitrary basic conditions was $24.46^{\circ}C$ (12 a.m.)

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.571-586
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• 2014

Moderate Resolution Imaging Spectroradiometer (MODIS) provides air temperature (Tair) and dew point temperature (Tdew) profiles at a spatial resolution of 5 km. New Collection 6 (C006) MODIS07_L2 atmospheric profile product has been produced since 2012. The Collection 6 algorithm has several modifications from the previous Collection 5 (C005) algorithm. This study evaluated reliabilities of two alternative datasets of surface-level Tair and Tdew derived from C005 and C006 Aqua MODIS07_L2 (MYD07_L2) products using ground measured temperatures from 77 National Weather Stations (NWS). Saturated and actual vapor pressures were calculated using MYD07_L2 Tair and Tdew. The C006 Tair showed lower mean error (ME, -0.76 K) and root mean square error (RMSE, 3.34 K) than the C005 Tair (ME = -1.89 K, RMSE = 4.06 K). In contrasts, ME and RMSE of C006 Tdew were higher than those (ME = -0.39 K, RMSE = 5.65 K) of C005 product. Application of ambient lapse rate for Tair showed appreciable improvements of estimation accuracy for both of C005 and C006, though this modification slightly increased errors in C006 Tdew. The C006 products provided better estimation of vapor pressure datasets than the C005-derived vapor pressure. Our results indicate that, except for Tdew, C006 MYD07_L2 product showed better reliability for the region of South Korea than the C005 products.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.46-58
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• 2017

Objectives: Particulate matter (PM) at construction sites mostly originates from either construction activities or the atmospheric environment. This study was conducted to evaluate the exposure level to PM and the contribution ratio of atmosphere sources at construction sites. Methods: We reviewed literature and governmental systems related to PM exposure in occupational settings and summarized them. In the field evaluation, five construction sites and one golf course were selected: two from Gyeonggi-do Province and four from North Gyeongsang-do Province. For each site, personal samples from outdoor construction workers and area samples from the outdoor area around the construction site office were collected according to construction work types. PM concentrations reported from nearby National Ambient Air Monitoring Stations were recorded. Respirable dust concentrations, respirable silica concentrations, and several metal concentrations including Cd, Cr, Pb, and As were monitored over four months. In the end we suggested how to manage particulate matter exposure at construction sites. Results: There was little literature reporting on exposure levels of construction workers to PM. Respirable dust concentrations measured in Gyeonggi-do Province were higher than those measured in North Gyeongsang-do Province. The geometric means of respirable dust concentrations in personal samples and area samples were $37.89{\mu}g/m^3$ and $92.86{\mu}g/m^3$, respectively. The respirable dust concentrations were higher than the PM concentrations reported from nearby National Ambient Air Monitoring Station. The geometric means of respirable silica concentrations of personal samples and area samples were $1.3{\mu}g/m^3$ and $1.1{\mu}g/m^3$, respectively. All metal concentrations were lower than 10% of individual Korean occupational exposure limits. Conclusions: Assuming that personal samples consisted of ambient PM and dust originating from work activities and area samples only collected ambient PM, we concluded that the dust exposure of outdoor construction workers originated 40.8% from the atmosphere and 59.2% from construction activities. PM exposure at construction sites should be controlled by employers, as in the case of outdoor heat stress. The Korean government needs to consider setting an occupational exposure limit for respirable dust.

• Korean Journal of Remote Sensing
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• v.16 no.3
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• pp.243-260
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• 2000

Ocean remote sensing reflectance of just above water level was modeled using inherent optical properties of seawater contents, total absorption (a) and backscattering(bb) coefficients ($R_{rs}$=0.046 $b_b$/(a+$b_b$). This modeling was based on the specific absorption and backscattering coefficients of 5 optically active seawater components； phytoplankton pigments, non-chlorophyllous suspended particles, dissolved organic matters, heterotrophic microorganisms, and the other unknown particle components. Simulated remote sensing reflectance($R_{rs}$) and water leaving radiance(Lw) spectra were well agreed with in-situ measurements obtained using a bi-directional fields remote spectrometer in coastal waters and open ocean. $R_{rs}$ values in SeaWiFS bands from the model were analyzed to develop 2-band ratio ocean color chlorophyll with those observed insitu. Also, chlorophyll algorithm based on remote reflectance developed in this study fell in those obtained by a SeaBAM working group. The model algorithms were examined and compared with those observed insitu. Also, chlorophyll algorithm based on remote reflectance developed in this study fell in those obtained by a SeaBAM working group. The remote reflectance model will be very helpful to understand the variation of water leaving radiances caused by the various components in the seawater, and to develop new ocean color algorithm for CASE-II water using neural network method or other analytical method, and in the model of fine atmospheric signal correction.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.1035-1039
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• 2010

For 65 national forest areas in 1993 to 2008, the ambient sulfur dioxide ($SO_2$) concentrations were measured monthly using passive samplers and compared to the those of urban areas in order to investigate the characteristics of temporal and spatial distribution. In the forest areas, annual average concentration of sulfur dioxide gradually decreased from the beginning year of monitoring to 1997 and then had no significant change, such as the annual trend in urban areas monitored by Ministry of Environment. For the monitoring term, average concentration of sulfur dioxide in the forest areas was 5.6ppb, which was lower than the 10.1ppb in the urban areas and the EC ecological standard level (7.6 ppb). Seasonally, both in forest areas and urban areas the monthly average concentrations were much higher in winter and spring due to much more heating fuel consumption, and lowest in summer. Regional comparison to other regions of Gyeongbuk and Gyeonggi province showed that the concentration of sulfur dioxide was the highest during year. A significant positive correlation between sulfur oxides' emissions and sulfur dioxide concentration by province was observed, reflecting that the size and proximity of sources of atmospheric sulfur oxides could be important factors in determination.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1215-1227
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• 2021

Surface reflectance, as a product of the absolute atmospheric correction process of low-orbit satellite imagery, is the basic data required for accurate vegetation analysis. The Commission on Earth Observation Satellite (CEOS) has conducted research and guidance to produce analysis-ready data (ARD) on surface reflectance products for immediate use by users. However, this trend is still in the early stages of research dealing with ARD for high-resolution multispectral images such as KOMPSAT-3A and CAS-500, as it targets medium- to low-resolution satellite images. This study first summarizes the types of distribution of ARD data according to existing cases. The link between Open Data Cube (ODC), the cloud-based satellite image application platforms, and ARD data was also explained. As a result, we present practical ARD deployment steps for high-resolution satellite images and several types of application models in the conceptual level for high-resolution satellite images deployed in ODC and cloud environments. In addition, data pricing policies, accuracy quality issue, platform applicability, cloud environment issues, and international cooperation regarding the proposed implementation and application model were discussed. International organizations related to Earth observation satellites, such as Group on Earth Observations (GEO) and Committee on Earth Observation Satellites (CEOS), are continuing to develop system technologies and standards for the spread of ARD and ODC, and these achievements are expanding to the private sector. Therefore, a satellite-holder country looking for worldwide markets for satellite images must develop a strategy to respond to this international trend.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.461-468
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• 2019

Demand for improving dust removal efficiency in coal power plants and the dust removal requirement to the level of capturing fine particulate matter and ultrafine particles have been increasing. While bag filter and electrostatic precipitator (ESP) are typically used for dust removal in the processes operating at atmospheric pressure, metal filters or ceramic filters are employed for dust which is produced at high temperature/pressure system as in coal gasification. For dust removal at the high temperature/pressure conditions, two metal filters of five compressed/sintered layers were manufactured and applied to analyze the dust removal characteristics. Manufactured metal filters exhibited more than 99% dust removal efficiency on coal gasification fine particulates in mass basis. To evaluate the fine particulate removal efficiency of less than $2.5{\mu}m$, JIS standard fine sample was used and confirmed the removal efficiencies of 97% and 70~82% on the fine particulates of $1{\sim}2.5{\mu}m$ size range. For the size range of less than $1{\mu}m$, dust removal efficiency of manufactured metal filters significantly degraded with smaller particle size. Improving methods are proposed to overcome the limitations in applying to fine dust of less than $1{\mu}m$.

• Journal of the Korean earth science society
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• v.40 no.2
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• pp.188-199
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• 2019

The purpose of this study was to investigate the tendency of inquiry of earth science content presented in North Korean textbooks of the 2013 National curriculum using Romey's method, and to help use as basic data for better understanding earth science education in North Korea. The content of earth science in the text, figure, question, and activity index of textbooks of Natural Science 1 and 2, Chosun Geography 2 of elementary junior high school, and of Geography 1 of advanced junior high school were all analyzed using Romey's method. The results of this study were as follows: First, the atmospheric science question and the astronomy text showed the tendency of inquiry type. Second, the proportion of oceanography was relatively small. Third, there were many non-inquiry questions or excessive inquiry questions, and both types of questions needed to be balanced. Fourth, there were a tendency that did not emphasize inquiry learning. Finally, the quantitative and qualitative level of inquiry tendency should be improved. In this paper, we propose to use a qualitative method when analyzing earth science content in North Korean textbooks, and suggested that we should further study the comparative analysis of inquiry tendency of earth science content using South and North Korean textbooks.