• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.12
• /
• pp.867-876
• /
• 2013

To promote the carbon emission trading scheme and reduce greenhouse gas (GHG) emission as following 'Korean GHG & Energy Target Management System', GHG emissions should be accurately determined in each industrial sector. For the estimation method of GHG emission from waste landfill, there are several error parameters, therefore we reviewed the estimation method and proposed a revised method. Methane generation from landfill must be calculated by the selected method based on methane recovery rate, 0.75. However, this methodology is not considered about uncertainty factor. So it is desirable that $CH_4$ generation is estimated using first order decay model and methane recovery should use field monitoring data. If not, $CH_4$ recovery could be applied from other study results; 0.60 of operational landfill with gas vent and flaring system, 0.65 of operational site with landfill gas recovery system, 0.90 of closed landfill with final cover. Other parameters such as degradable organic carbon (DOC) and fraction of DOC decompose ($DOC_f$) need to derive the default value from studies to reflect a Korean waste status. Proper application of MCF that is selected by operation and management of landfill requires more precise criteria.

• Journal of Soil and Groundwater Environment
• /
• v.8 no.2
• /
• pp.55-61
• /
• 2003

The objective of this study was to investigate the characteristics of nitrate removal by conducting the column test in order to see the performance of surfactant modified zeolite (SMZ) as a permeable reactive barrier material. The prediction of nitrate removal was tested using the one-dimensional advective-dispersive model fitted to the experimental breakthrough curve. A methodology for scaling up to in-situ permeable reactive barrier was also proposed. The breakthrough of nitrate in the column packed with SMZ was well predicted using linear equilibrium adsorption model. The breakthrough time and half-life obtained by breakthrough experiment with variation of flowrates were decreased with the increase of flowrates. When 10㎥/day of groundwater containing the 50 mg/l of nitrate is to be treated to satisfy the potable water quality criteria (10 mg/l) by SMZ reactive barrier, 300 tons of SMZ and about 6 years of breakthrough time will be required, suggesting that 165 million wons are needed as barrier material expenses in each 6 years besides the initial design and construction expenses and the minimal monitoring and maintenance expenses.

• Economic and Environmental Geology
• /
• v.40 no.5
• /
• pp.563-574
• /
• 2007

Laser induced breakdown spectroscopy (LIBS) is a recently developed analytical technique that is based upon the measurement of emission lines generated by atomic species close to the surface of the sample, thus allowing their chemical detection, identification and quantification. With powerful advantages of LIBS compared to the conventional analytical methodology, this technique can be applied in the detection of heavy metals in the field. LIBS allows the rapid analysis by avoiding laborious chemical steps. LES have already been applied for the determination of element concentration in a wide range of materials in the solid, liquid and gaseous phase with simplicity of the instrument and diversity of the analytical application. These feasibility of rapid multi elemental analysis are appealing proprieties for the in-situ analytical technique in geochemical investigation, exploration and environmental analysis. There remain still some limitations to be solved for LIBS to be applied in soil environment as an in-situ analytical technology. We would like to provide the basic principle related to the plasma formation and laser-induced breakdown of sample materials. In addition, the matrix effect, laser properties and the various factors affecting on the analytical signal of LIBS was dealt with to enhance understanding of LIBS through literature review. Ultimately, it was investigated the feasibility of LIBS application in soil environment monitoring by considering the basic idea to enhance the data quality of LIBS including the calibration method for the various effects on the analytical signal of LIBS.

• Korean Journal of Food Science and Technology
• /
• v.29 no.4
• /
• pp.737-744
• /
• 1997

Four-dimensional response surface methodology was used for optimizing preparation conditions and monitoring sensory quality of instant rice gruel prepared using oyster mushroom and brown rice. Water absorption time of brown rice and glutinous rice to prepare instant rice gruel were 50 hr at $5^{\circ}C\;and\;1\;hr\;at\;20^{\circ}C$, respectively. The optimum conditions predicted for each corresponding sensory properties of instant rice gruel were 47.58% (rate of brown rice in water-absorbed brown and glutinous rice), 569.68 mL (content of solution) and 52.40 min (heating time at $120^{\circ}C$) in viscosity of instant rice gruel, 47.15%, 568.49 mL and 53.04 min in taste of instant rice gruel, 44.06%, 558.54 mL and 53.84 min in mouth-feel of instant rice gruel, and 46.20%, 561.64 mL and 51.60 min in overall acceptance of instant rice gruel, respectively. The optimum conditions, which satisfy all sensory properties of rice gruel, were 44%, 620 mL and 56 min in rate of brown rice in water-absorbed brown and glutinous rice, content of solution and heating time, respectively. Sensory scores predicted at the optimum conditions were in good agreement with experimental sensory scores.

• Journal of Distribution Science
• /
• v.16 no.8
• /
• pp.63-68
• /
• 2018

Purpose - Lettuce (Lactuca sativ L.) is one of the economically important vegetable crops, which worldwide market value is over 100 billion U.S. dollar. In Korea, about 89.7 kilo ton of lettuce was produced in 3400ha in 2016, recoded as No. 1 vegetable crop in domestic green house production. However, recently, domestic lettuce production and cultivation areas are all getting decreased. Thus, novel approaches are needed to be implemented to revive the production. Research design, data and methodology - In this review paper, we first prioritized the end-user traits which are imperative to positively stimulate the domestic lettuce market and discussed relevant genomics strategies. Especially, we assessed a possibility whether school meal program would be a potential niche market. Results - The genomics technologies, which become widely applied in the crop biotechnology since 2008 when next generation sequencing method was developed, may be a good solution in the crop improvement, efficiently gathering valuable information of agriculturally useful traits. Significantly, in lettuce, the high quality whole genome sequence, based on Lactuca sativa cv. Salinas, is publically available and this genomics platform, thus, would be implemented in lettuce breeding program to innovate relevant end-user traits both for the farmers and customers, including the disease resistance to the Fusarium wilt, productivity under hot weather conditions, various nutritional qualities and so forth. These improvements will boost domestic lettuce industries in the near future. Conclusions - Due to the nutritional distinctions comparing to the western style lettuces, domestic leaf lettuces could be one of the important vegetables in the school meal programs. To make it happen, we would better devise diverse recipes to make a salad with it, instead of only using as a wrap vegetable. Meanwhile, novel lettuce varieties need to be developed, which are favorable to the students and also easy to be handled with while processing. Overall, to achieve international competence in the lettuce industries, we need to create elite lettuce varieties that satisfies domestic farmers as well as customers, suitable to various niche markets, such as school meal program. Thus, efficient breeding programs using genomics approaches should be established in advance and careful monitoring on the preference of the related customers for a niche market be continued persistently.

• Food Science and Preservation
• /
• v.20 no.4
• /
• pp.532-538
• /
• 2013

This study was done in order to monitor the quality properties of the granule using Bokbunja (Rubus coreanus Miquel) extracts. In order to prepare the granule depending on operational parameters such as content of Bokbunja extract ($X_1$, 0.4~1.2 g), sugar content ($X_2$, 6~10 g) and citric acid content ($X_3$, 0.1~0.3 g), a response surface methodology was applied to monitor the optimum recipes on the organoleptic properties and Hunter's color. The optimum recipe on the organoleptic color showed extract content of 0.96 g, sugar content of 7.05 g and citric acid content of 0.232 g. The optimum recipe on the organoleptic flavor showed extract content of 0.86 g, sugar content of 6.04 g and citric acid content of 0.215 g. The optimum recipe on the organoleptic taste showed extract content of 0.92 g, sugar content of 6.39 g and citric acid content of 0.251 g. The optimum recipe on the overall palatability showed extract content of 0.86 g, sugar content of 6.65 g and citric acid content of 0.272 g. The response surface of the Hunter's color b value was similar to the response of the overall palatability; therefore, the optimum conditions accepted by the consumers were 0.8 g Bokbunja extract content and 0.6 g sugar content in the Hunter's color a value of 6.0.

• Food Science and Preservation
• /
• v.10 no.2
• /
• pp.219-223
• /
• 2003

Response surface methodology was used for monitoring and optimizing the extraction conditions of campesterol, stigmasterol, ${\beta}$ -sitosterol, and total sterols from the safflower seed. The conditions of phytosterol extraction were optimized by using central composite design with the temperature(35∼75$^{\circ}C$, X$_1$), the time (1∼11hr, X$_2$), and the preheating temperature(60∼100$^{\circ}C$, X$_3$) as three variables. The extraction conditions for maximum campesterol content were 59.01$^{\circ}C$(X$_1$), 2.88hr(X$_2$), and 75.04$^{\circ}C$(X$_3$). But stigmasterol, ${\beta}$ -sitosterol and total sterols were not significantly different under designed extraction condition in this study. Besides, oil was extracted from safflower seed at various conditions and yields were 23.44% at 35$^{\circ}C$ and 20.05% at 80$^{\circ}C$, respectively. Total tocopherol content increased from 0.172% to 0.207% as the extraction temperature increased from 35$^{\circ}C$ to 80$^{\circ}C$. A structured lipids(SL) was synthesized enzymatically by extracted safflower oil and conjugated linoleic acid(CLA). After 24hr reaction, 31.79 mol% CLA was incorporated into the extracted safflower oil.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.32 no.2
• /
• pp.133-142
• /
• 2014

Landsat is one of the popular satellites for observing land surface that is used in various areas including monitoring, detecting and classifying changes in land surface. However, shades, which cloud itself and its shadow, interrupted often clear observation and analysis of ground surface. For this reason, the process of removing shades and restoring original ground surfaces are critical for geospatial users. This study is planned to recommend a methodology for more accurate and clear images of Landsat-8 sensor, which provided two additional bands of costal/aerosol and cirrus. In fact, those bands are known as functioned effectively in detecting and restoring shades. Otsu's thresholding technique to detect clouds, we replaced those detective shades by using experimental and reference images. In accurate assessment, the overall accuracy and kappa coefficients were about 85% and 0.7128, respectively. This indicates that the proposed technique is effective for recovering the original land surface.

• Journal of Korea Water Resources Association
• /
• v.53 no.11
• /
• pp.1015-1024
• /
• 2020

Recently, water pollution accidents have continued to occur in pipelines such as red water Incheon and Seoul. In order to recognize this water quality problem, it is necessary to install a water quality sensor in an appropriate location and measure it in advance to detect or block the water supply to the water faucet of the shelter. However, there are limitations, such as maintenance costs, to installing multiple water meters in all pipelines. Therefore, this study proposed a methodology for determining and prioritizing the installation location of flow-based water quality sensor for the recognition of water quality problems in pipelines. We applied the proposed procedure to the pipe break scenario. The results of the determination of the location of the water quality sensor were presented by applying it to the pipe network that actually operates the emergency pipe in Korea. The result of the decision showed that in the event of abnormal situation caused by the destruction of individual pipes, the flow rate of the pipes around the aqueduct and the tank may change rapidly, resulting in water quality accidents caused by turbidity. In the future, it is expected that the water quality monitoring point selection method, such as establishing an external pipe operation plan for pipe cleaning, will utilize the procedure for determining the location of the water quality sensor according to the velocity.

• Journal of Korean Society for Atmospheric Environment
• /
• v.32 no.2
• /
• pp.216-232
• /
• 2016

In present, the Seoul City is undergoing traffic congestion problems caused by rapid urbanization and population growth. Thus the City government has reorganized the mass transportation system since 2004 and the subway has become a very important means for public transit. Since the subway system is typically a closed environment, the indoor air quality issues have often raised by the public. Especially since a huge amount of PM (particulate matter) is emitted from ground tunnels passing through the subway train, it is now necessary to assess the characteristics and behaviors of fine PM inside the tunnel. In this study, the concentration patterns of $PM_1$, $PM_{2.5}$, and $PM_{10}$ in the Seoul subway line-2 were analyzed by real-time measurement during winter (Jan 13, 2015) and summer (Aug 7, 2015). The line-2 consisting of 51 stations is the most busy circular line in Seoul having the railway of 60.2 km length. The the one-day average $PM_{10}$ concentrations were $148{\mu}g/m^3$ in winter and $66.3{\mu}g/m^3$ in summer and $PM_{2.5}$ concentrations were $118{\mu}g/m^3$ and $58.5{\mu}g/m^3$, respectively. The $PM_{2.5}/PM_{10}$ ratio in the underground tunnel was lower than the outdoor ratio and also the ratio in summer is higher than in winter. Further the study examined structural types of underground subsections to explain the patterns of elevated PM concentrations in the line-2. The subsections showing high PM concentration have longer track, shorter curvature radius, and farther from the outdoor stations. We also estimated the outdoor PM concentrations near each station by a spatial statistical analysis using the $PM_{10}$ data obtained from the 40 Seoul Monitoring Sites, and further we calculated $PM_{2.5}/PM_{10}$ and $PM_1/PM_{10}$ mass ratios near the outdoor subway stations by using our observed outdoor $PM_1$, $PM_{2.5}$, and $PM_{10}$ data. Finally, we could develop pollution maps for outdoor $PM_1$ and $PM_{2.5}$ near the line-2 by using the kriging method in spatial analysis. This methodology may help to utilize existing $PM_{10}$ database when managing and control fine particle problems in Korea.