• Journal of Convergence for Information Technology
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• v.11 no.4
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• pp.122-129
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• 2021

As the total organic carbon (TOC) becomes a new water quality standard as an organic matter (OM) index for public sewage treatment facilities (PSTFs) in Korea from 2021, a comparison study needs to be conducted by examining the correlation between TOC and the existing OM indices (DOC, BOD5, CODMn, CODCr). 500 PSTFs were categorized by process configuration and capacity, and correlation between OM indices in influent and effluent was analyzed. The CODMn/TOC showed higher correlation than other OM indices. This results can be used to basic data for various research associated with TOC.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.91-95
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• 2001

In this study, we estimated the behavior of the diversity of physiological responses under varied physical environmental factors by measuring variations of heart rate variability (HRV), an index of activity of cardiac autonomic control. Seven healthy young male adults consented and participated in the study. The environmental conditions consisted of thermal, lighting, and acoustic conditions. Two components of HRV were measured. one was the low frequency (LF) component of HRV, which provided a quantitative index of the sympathetic and parasympathetic (vagal) activities controlling the heart rate (HR). The other component measured was the high frequency (HF) component, which provided an index of the vagal tone. The percent contribution of physical environmental factors to the variations in HRV indices were calculated by ANOVA. The contribution of physical environmental factors to the variations in HR was higher than the contribution of HF and LF. However, the contribution of these factors was lower than the contribution related with individual difference in all indices. This result showed that the individual diversity of physiological responses is not a negligible quantity.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.6
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• pp.63-68
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• 2009

Most of agricultural reservoirs in Korea have no function of flood control except 5% of reservoirs even exposed to natural disaster. In addition, there are increasing needs for the reservoir to guarantee the release of environmental flow to the downstream. Thus, the purpose of this paper is to study the priority decision method for the reservoir redevelopment satisfying both water utilization and flood control. The major scopes of this research are to set up six priority indices and to make needed GIS data for calculating each priority. There is important consideration of obtaining the data or not in deciding the indices. Although the detailed indices is expected to better reflect redevelopment priority but the subjective indices like, 'opinion' and 'landscape' are excluded. From the results, it will enables the six priority indices to really assist in decision redevelopment priority of agricultural reservoirs.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.784-795
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• 2006

The purpose of this study was to assess biological river water quality by using epilithic diatoms at 40 selected sites in Geum, Youngsan, and Seomjin River systems. The sampling and analyses were performed during three seasons including January, April and June in 2005. Various water quality parameters also were analyzed. We attempted to classify the water quality condition by epilithic diatom indices (DAIpo and TDI) with the results of corresponding analyses of various chemical water quality parameters. A five class system was delivered to describe the water quality condition ranged from "very good" to "very poor." We also proposed a way of classifying water quality condition by combining two diatom indices of DAIpo and TDI. Our results showed that biomass of epilithic diatoms varied not only seasonally but spatially; it was not likely that winter diatoms represent average water quality condition, due to high concentration of nutrients. Water quality status assessed by diatom indices was generally worse than that assessed by BOD, indicating that BOD standard likely underestimates the biological condition of the water body. Importantly, nutrient-based diatom index (TDI) generally overestimated organic matter-based index (DAIpo) at most study sites, indicating that diatoms in studied rivers were likely more affected by nutrients than organic matter. Thus, management strategy to improve river water quality in Korea is suggested to emphasize more on the nutrients than organic matters.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.560-567
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• 2009

Treated or untreated wastewater may be a major source of refractory organic matters (R-OM) in drinking water sources. For this study, spectroscopic characteristics of wastewater OM were investigated using the samples from 20 wastewater treatment plants, which are located at the upstream of the lake Paldang, to suggest a estimate index for R-OM in wastewater. R-OM was quantified by measuring total organic carbon (TOC) concentration of the wastewater samples remaining after 28-day dark incubation. Among the traditional OM indices such as chemical oxygen demand (COD) and initial TOC, CODMn showed the lowest correlation coefficients with R-TOC of the samples. The ratios of carbonaceous biochemical oxygen demand (CBOD) to $COD_{Cr}$ had a better correlation with the percent distribution of R-OM than $BOD/COD_{Cr}$ ratios. terrestrial humic-like fluorescence (THLF) exhibited the highest correlation coefficient with R-TOC among the indices obtained from the synchronous fluorescence spectra of the samples. Milori index, one of the humification indices, showed a good correlation with the percent distribution of wastewater. This study demonstrated that fluorescence properties might be a better indices to estimate the concentrations and the distributions of wastewater OM compared to the specific UV absorbance (SUVA) values. Some useful formulas based on OM spectroscopic characteristics were finally suggested to predict R-OM in wastewater.

• Environmental Engineering Research
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• v.16 no.3
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• pp.175-183
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• 2011

The climate of the $21^{st}$ century is likely to be significantly different from that of the 20th century because of human-induced climate change. An extreme weather event is defined as a climate phenomenon that has not been observed for the past 30 years and that may have occurred by climate change and climate variability. The abnormal climate change can induce natural disasters such as floods, droughts, typhoons, heavy snow, etc. How will the frequency and intensity of extreme weather events be affected by the global warming change in the $21^{st}$ century? This could be a quite interesting matter of concern to the hydrologists who will forecast the extreme weather events for preventing future natural disasters. In this study, we establish the extreme indices and analyze the trend of extreme weather events using extreme indices estimated from the observed data of 66 stations controlled by the Korea Meteorological Administration (KMA) in Korea. These analyses showed that spatially coherent and statistically significant changes in the extreme events of temperature and rainfall have occurred. Under the global climate change, Korea, unlike in the past, is now being affected by extreme weather events such as heavy rain and abnormal temperatures in addition to changes in climate phenomena.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.760-768
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• 2011

Jinwi Stream is considerably polluted. The urban development in a Jinwi Stream basin can make state of aquatic ecosystem worse. However, researches for aquatic ecosystems in Jinwi Stream are insufficient. In this study, biotic indices of periphytic diatoms (DAIpo and TDI), benthic macroinvertebrates (EPT, KSI and ESB) and fish (IBI) were compared with the annual water quality data. Benthic macroinvertebrates indices showed highly significant correlations with concentrations of organic materials and nutrients, while DAIpo, TDI and IBI showed low correlations with them. In particular, ESB can be considered as an useful indicator that reflects the degree of diversity and abundance of biotic community as well as water quality. In polluted and disturbed streams as Jinwi Stream, DAIpo, TDI and IBI appeared to be not available for evaluating and discriminating the water quality, although they have been known as good indices in general streams.

• Environmental and Resource Economics Review
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• v.16 no.3
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• pp.549-574
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• 2007

This paper was intended to evaluate environmental policies of South Korea and compare its environmental sustainability with other Eastern Asian countries in terms of some sustainability measures. To meet the purpose, the paper is composed of three parts: a brief and critical review of Korea's current environmental policies, comparison of its sustainability with other Eastern Asian countries in terms of well-known environmental sustainability indices, and comparison in terms of a less well-known alternative measure. Korea's environmental policies as stipulated in "Green Vision 21", "Green Korea 2005" were evaluated in light of OECD EPRK 2006. Korea's environmental performance is then compared with other countries based on such environmental sustainability indices as EF, ESI, EPI and EVI. Unfortunately the well-publicized indices to measure sustainable development (SD) seem to fail in measunng SD and in providing comparability, because it does not base on the genuine concept of SD. Therefore, we tried to suggest an alternative measurement in terms of sustainability quantity (SQ), which is presented for South Korea and her major trading partners, such as USA, Japan and China.

• Journal of Korea Water Resources Association
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• v.39 no.9 s.170
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• pp.787-800
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• 2006

This study is to develop the drought monitoring system of Korea using drought indices such as PDSI, SPI and MSWSI. To analyze the applicability of three different drought indices, monthly based drought indices have been calculated using various kinds of meteorological and hydrologic data. Also past drought events have been investigated to compare the simulation results, which are the severity, duration and locations using monthly drought indices. The drought map which is made by using PDSI shows the best accordance with past drought events in its severity and duration as well. Also SPI(3) shows good accordance with past drought events. As a results of this study, we concluded that three different drought indices can be used as an effective tool for quantitative drought monitoring.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.135-151
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• 2015

DMZ is considered as an ecologically sensitive landscape and one of the highest biodiversity regions in the Republic of Korea. There have been, albeit the significant value, increased interests in developing this region for a variety of purposes including tourism and commemorative events. As this region has been already facing a range of problems derived from previous development, natural disaster and invasive species, the necessity for active management of ecological health within this region has been increased, which weighs the importance of executing ecological restoration. The objective of this study was to develop evaluation indices as an effective management means of properly evaluating ecological restoration and sustainably maintaining the restored conditions on a long-term scale. Through literature review existing evaluation indices related to restoration were collected, and then the most suitable indices were selected based upon two interviews and one questionnaire survey targeting experts in the relevant field to ecological restoration. They were categorized by two major division and their subclasses (Ecological base - vegetation structure & composition, habitat characteristics, soil environment; landscape ecology - connectivity, landscape patch, boundary & surrounding) and 40 indices. These indices were considered helpful to comprehensively evaluate ecological restoration on degraded environments within ecologically sensitive areas, and sustainably manage target areas by employing a long-term monitoring approach. As this result played a meaningful role in providing the fundamentals of evaluating ecological restoration, it should develop a suitable evaluation system through further research.