• Journal of Korean Society of Water and Wastewater
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• v.30 no.1
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• pp.59-67
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• 2016

Owing to time and cost constraints, new methods that would make it possible to evaluate the safety of the water supply pipeline in a less time- and cost-consuming manner are urgently needed. In response to this exigency, the present study developed a new statistical model to assess the safety of the water supply pipeline using the quantification theory type II. In this research, the safety of the water supply pipeline was defined as 'a possibility of the pipeline failure'. Quantification analysis was conducted on the qualitative data, such as pipe material, coating, and buried condition. The results of analyses demonstrate that the hit ratio of the quantification function amounted to 77.8% of hit ratio, which was a fair value. In addition, all variables that were included in the quantification function were logically valid and demonstrated statistically significant. According to the results derived from the application of the safety evaluation model, the coefficient of determination ($R^2$) between K-region's water supply pipeline safety and the safety inspection amounted to 0.80. Therefore, these findings provide meaningful insight for the measured values in real applications of the model. The results of the present study can also be meaningfully used in further research on safety evaluation of pipelines, establishing of renewal prioritization, as well as asset management planning of the water supply infrastructure.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.5
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• pp.29-37
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• 2018

Biodiversity refers to the diversity of organisms originating from all sources, including terrestrial ecosystems, aquatic ecosystems, and complex ecosystems and it is considered to be the standard of the area to be preserved and protected. So The Importance of environmental assessment for biodiversity conservation is increasing and International efforts to quantify biodiversity and to develop indices have been made, but there are insufficient researches on the use of biomass databases and their quantification in Korea. In this study, the biodiversity map was constructed using the 3rd National Ecosystem Survey Mammal Data with three spatial units(Administrative Area, 1:5,000 index map, hexagonal lattice). and the difference of map constructed by spatial unit was suggested to help research on quantification and evaluation of biodiversity in the future. As a result of the study, biodiversity index for the same area varied according to the spatial unit and overall average and standard deviation were different too. Therefore it is necessary to utilize appropriate spatial unit considering the suitability and purpose of quantification rather than using specific unit. It also showed the necessity of establishing a standard for biodiversity index as a result of comparative analysis with ecosystem and nature map. Based on this research, comprehensive efforts should be made for the sustainable development of the country through further research and institutional improvement for quantification and evaluation of biodiversity, set standards.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.4
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• pp.1-15
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• 2014

Forest ecosystems generate variety of important goods and services for human well-being. As a growing concern of climate change and water shortage, it is necessary to quantify, model and map water balance in forest. In this study, we have analyzed 11 overseas forest water supply models (AIM, ATEAM, CENTURY, (E)SWAT, GUMBO, InVEST, PLM, SAVANNA, WaSSI, WaterGAP, WBM) and compared their scale, input and out data, availability of the models and analyzed the applicability of the models to Korea. As a result, InVEST and WaterGAP model appeared to be applicable for quantifying water provisioning services in Korea. A systematic approach for applying to evaluate water balance in forest was suggested based on our quantification approach.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.854-859
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• 2018

Calculating minimal cut sets is a typical quantification method used to evaluate the top event probability for a fault tree. If minimal cut sets cannot be calculated or if the accuracy of the quantification result is in doubt, the Monte Carlo method can provide an alternative for fault tree quantification. The Monte Carlo method for fault tree quantification tends to take a long time because it repeats the calculation for a large number of samples. Herein, proposal is made to improve the quantification algorithm of a fault tree with circular logic. We developed a top-down iteration algorithm that combines the characteristics of the top-down approach and the iteration approach, thereby reducing the computation time of the Monte Carlo method.

• Journal of the Korean earth science society
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• v.28 no.5
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• pp.572-584
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• 2007

The quantification of ammonia concentrations has received a lot of scientific attention. Numerous devices for the quantification of $NH_3$ in the ambient air have been developed to provide more technical possibilities for research in abating $NH_3$ emission from various source processes. For the proper quantification of $NH_3$, a number of sampling methods have been discussed by grouping them into different categories based on the principle of functioning. In general, active samplers employ pumps to draw air in, while passive samplers are exposed to air over a certain period of time to obtain integrated signature of $NH_3$. In case of the former, impingers and absorption flasks can be employed simultaneously with suitable absorbents to capture $NH_3$ passing through them. The methods of analysis include both in-situ and laboratory determination. In the laboratory, colorimetric or ion chromatographic methods are generally used for its quantification. In the field, a number of real time analyzers have been proven to be useful. These real time analyzers can be grouped according to their principle of operation. These analyzers may use the principle of spectroscopy (e.g. DOAS), photoacousticics (e.g. photoacoustic monitor) or Chemiluminescence ($NO_x$ analyzer). The automated annular denuder sampling system with on-line analyzer is also suitable for continuous monitoring of ammonia in air.

• Journal of Environmental Impact Assessment
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• v.6 no.2
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• pp.165-180
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• 1997

Mitigation measures in EIS are the important factors in the effectiveness of EIS. This paper analyzed the content of mitigation measures described in the 30 EISs selected, using 7 analysis items in order to discover the degree of effectiveness of mitigation measures. 30 EISs used in this study were selected through variance maximization strategy, and the 7 analysis items were; 1) thoroughness of mitigation content, 2) quantification of mitigation content, 3) explicit description of mitigation effect, 4) likelihood of mitigation effect, 5) impacted area of mitigation effect, 6) time frame of mitigation effect, and 7) environmental impact of mitigation measures. The results showed that the effectiveness of mitigation measures in the analyzed EISs was relatively low both in the appropriateness and in the specificity. It was suggested that in order to improve the appropriateness of EIS as a decision making tool, the effect of mitigation measures, as well as the mitigation measures themselves, should be studied and described more thoroughly and specifically.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.118-121
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• 2003

A method for detection and quantification of aceticlastic methanogens using a real-time PCR with a TaqMan probe was developed. Two sets of primers and probes targeting the family Methanosarcinaceae and Methanosaetaceae were designed by using the Ribosormal Database Project (RDP) II, and softwares for phylogenetic probe design and sequence analysis. Target-group specificity of each set of primers and probe was verified by testing DNAs isolated from pure cultures of 28 archaeal strains purchased from DSMZ. Cell numbers in the 28 archaeal cultures and in the samples from anaerobic processes were quantified using a real-time PCR with the sets of primers and probe. In conclusion, the real-time PCR assay was very specific for the corresponding target methanogenic family and was proved to be a powerful method for quantification of aceticlastic methanogens in anaerobic processes.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.428-434
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• 2022

This study was conducted to derive the site index of forest productivity of Robinia pseudoacacia (honey plant) to characterize suitable planting sites and to investigate the effect of the site environmental factors on the site index using the quantification theory I method. The data used in the analysis were growth factors (stand age, dominant height, etc.) of the 6th national forest resources survey and various site environmental factors of a forest soil map (1:5,000). The average site index value of the R. pseudoacacia stand in Korea was 14 (range, 8 to 18). The environmental factors affecting the site index were parent rock, climatic zone, soil texture, local topography, and altitude. The accuracy of the estimation model using quantification theory I was only 33%. However, the correlation between the site index and the site environmental factors was statistically significant at the 1% level. Results of quantification analysis between site index and site environmental factors revealed that metamorphic and igneous rocks received high grades as parent rocks, climate zones received higher grades than central temperate zone, clay loam and silt loam received high grades in soil texture, and hillside received a high grade in local topography. Analysis of the partial correlation between site topographical factors and forest productivity (site index) found that soil class and altitude were partially correlated to x by 0.4129 and 0.4023, respectively, indicating that these factors are the most influential variables.

• Analytical Science and Technology
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• v.15 no.1
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• pp.43-53
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• 2002

The analysis of polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzo furans(PCDFs) was performed by using four different gas chromatographic columns (SP-2331, DB-5, DB-17 and DB-DIOXIN). The data reported is pertaining to flue gas, fly ash, ambient air, soil and fish. The difference in quantification of samples according to four columns was observed, it was noted that major difference was observed in the flue gas when compared with soil, fly ash, ambient air and fish. The quantification of the same samples according to four columns it was also found that DB-5 column have the highest concentration whereas SP-2331 column showed the lowest concentration. The quantification of DB-17 column for 1,2,3,6,7,8-HxCDF was found to be twice and three times higher when compared with other columns, whereas the quantification of DB-DIOXIN column for 1,2,3,7,8-PeCDD was also found to be over estimated twice when compared with other columns.

• Smart Structures and Systems
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• v.22 no.4
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• pp.399-411
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• 2018

The difficulty in modeling complex nonlinear structures lies in the presence of significant sources of uncertainties mainly attributed to sudden changes in the structure's behavior caused by regular aging factors or extreme events. Quantifying these uncertainties and accurately representing them within the complex mathematical framework of Structural Health Monitoring (SHM) are significantly essential for system identification and damage detection purposes. This study highlights the importance of uncertainty quantification in SHM frameworks, and presents a comparative analysis between intrusive and non-intrusive techniques in quantifying uncertainties for SHM purposes through two different variations of the Kalman Filter (KF) method, the Ensemble Kalman filter (EnKF) and the Polynomial Chaos Kalman Filter (PCKF). The comparative analysis is based on a numerical example that consists of a four degrees-of-freedom (DOF) system, comprising Bouc-Wen hysteretic behavior and subjected to El-Centro earthquake excitation. The comparison is based on the ability of each technique to quantify the different sources of uncertainty for SHM purposes and to accurately approximate the system state and parameters when compared to the true state with the least computational burden. While the results show that both filters are able to locate the damage in space and time and to accurately estimate the system responses and unknown parameters, the computational cost of PCKF is shown to be less than that of EnKF for a similar level of numerical accuracy.