• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.666-677
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• 2019

In order to understand the distribution of organic matter and heavy metal concentrations in the surface sediments of fishery resources protection areas (FRPAs), we measured the grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and concentrations of heavy metals (As, Cd, Cr, Cu, Fe, Hg, Pb, and Zn) in the surface sediments collected at 54 stations of 5 FRPAs (Gamak Bay, Yeoja Bay, Deukryang Bay, Wando coast, and Youngkwang coast) in the southwestern coast of Korea in February 2017. The surface sediments consisted of fine sediment such as mud, with 2.9~8.8Ø (7.4±0.1Ø) of mean grain size. The average concentrations of IL, COD, and AVS in the sediments were 4.63±0.96 %, 13.0±3.1 mgO₂/g·dry, and 0.092±0.124 mgS/g·dry, respectively, and were lower for sediments from the Youngkwang coast than those from other FRPAs. The average concentrations of heavy metals in the sediment were 7.5±0.9 mg/kg for As, 0.04±0.02 mg/kg for Cd, 70.2±9.7 mg/kg for Cr, 15.3±2.8 mg/kg for Cu, 3.3±0.5 % for Fe, 0.014±0.003 mg/kg for Hg, 25.0±6.0 mg/kg for Pb, and 99±14 mg/kg for Zn, respectively, and were relatively higher for sediments in the inner bays than those from the outer bays and coasts. Based on the assessment of sediment samples using the sediment quality guidelines (SQGs), the pollutant load index (PLI), and the ecological risk index (ERI), the surface sediments of FRPAs in the southwestern coast of Korea do not appear to be polluted by heavy metals, suggesting that the heavy metal concentrations in the sediments would not adversely impact aquatic and benthic organisms.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.392-402
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• 2020

We investigated the concentrations of acid volatile sulfide (AVS), ignition loss (IL), total organic carbon (TOC), total nitrogen (TN), and metallic elements (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn), in August 2015, to determine the spatial distribution and pollution status of organic matter and metals in the surface sediment of Jinju Bay, a spraying shellfish farming area, Korea. The concentrations of organic matter and metallic elements were significantly higher in the southern part of the bay than in the mouth and center of the bay. The C/N ratio (5.7~8.0) in the sediment represents the dominance of organic matter of oceanic origin in the surface sediment of the study area. The concentrations of AVS, TOC, and metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) were much lower than the values of the sediment quality guidelines applied in Korea. Based on the results of the pollution load index (PLI) and ecological risk index (ERI), the metal concentrations in the surface sediment of Jinju Bay have a weakly negative ecological effect on benthic organisms although the sediments with high metal pollution status are distributed in the southern parts of the bay, with high dense shellfish farming areas. Thus, the surface sediments in Jinju Bay are not polluted with organic matter and are slightly polluted with metallic elements.

• Journal of Society of Preventive Korean Medicine
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• v.7 no.1
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• pp.1-15
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• 2003

This study tried to evaluate the difference of stress degree by Sasang constitution and lifestyle for workplace labors, and suggested the preventive oriental medicine approaches in occupational health area. 479 data for research were collected through the process of oriental health examination with questionnaire in workplace, and collected data were analyzed with frequency, crosstab, and Two-Way ANOVA. The results were as follows: 1) All subjects, total 479 were men, and constitutional distributions were 39.2% of Taeumin, 32.4% of Soumin, and 28.4% of Soyangin. The distributions of stress score were 13.2% of normal group, 13.4% of high risk group, and 73.5% of potential risk group. 2) There were no statistically significant differences for stress by constitution(p=0.085). By the results of optimal scaling and homogeneity analysis, Soyangin was close to potential risk group compared to other constitution, and Soumin and Taeumin were close to high risk and normal group, respectively. 3) For the difference of stress score by Sasang constitution and lifestyle, Soumin who exercised nearly everyday had the highest stress score with interaction in Factor 4 area(p<0.05), and there was no interaction in other area. 4) For the difference of PWI score by lifestyle, there were statistically significant differences for drinking(p<0.01), smoking(p<0.01), and obesity index(p<0.01)

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.982-982
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• 2012

본 연구에서는 우리나라의 중 소규모 유역의 수문학적 위험도 분석을 위하여 한강유역을 대상으로 통합위험지수(IRI: Integrated Risk Index)를 산정하였으며, El Ni$\tilde{n}$o-Southern Oscillation (ENSO)에 의한 대규모 대기순환 패턴의 변화가 한강 유역의 통합위험지수 변화에 미치는 영향을 평가하였다. ENSO자료는 전통적인 El Ni$\tilde{n}$o에 해당하는 Cold-tongue (CT) El Ni$\tilde{n}$o와 중앙태평양 부근의 이상적인 해수면 온도 상승에 의한 Warm-pool (WP) El Ni$\tilde{n}$o, 그리고 해수면 온도가 이상적으로 낮게 관측되는 La Ni$\tilde{n}$a 기간으로 구분하였으며, 각 기간 중 가장 강한 ENSO가 발생한 해(CT El Ni$\tilde{n}$o, 1998; WP El Ni$\tilde{n}$o, 2005; La Ni$\tilde{n}$a, 2000)를 대상으로 통합위험지수를 산정하였다. 통합위험지수는 수문학적 요인(Hydrologic Components), 사회 경제적 요인(Socio-Economic Components)과 생태적 요인(Ecological Components)으로 구분하였고, 엔트로피(entropy) 기법을 통하여 각 인자와 요인별 가중치를 적용하였다. 중권역별 통합위험지수의 평가는 5개의 계급구간(Very High, High, Medium, Low, Very Low)으로 구분하였다. 분석결과, CT El Ni$\tilde{n}$o해의 유역평균 IRI 값은 0.58, WP El Ni$\tilde{n}$o해의 IRI 값은 0.57로 비슷한 결과를 보였으나, La Ni$\tilde{n}$a해에는 IRI 값이 0.41로 낮게 나타났다. CT와 WP El Ni$\tilde{n}$o해에는 한강 서쪽일부 중권역에서 통합위험지수가 높게 나타났으며, La Ni$\tilde{n}$a해에는 한강 중 동부 대부분 유역에서 낮게 분석되었다. 향후 유역별 통합위험지수 산정과 더불어 서로 다른 형태의 ENSO에 따른 수자원 변동 예측이 이루어진다면, 수자원의 효율적인 관리와 안정적인 용수공급에 도움을 줄 것으로 사료되며, 이는 유역별 수자원의 취약성 평가 및 위험도 분석을 위한 기초자료로 활용이 가능하리라 사료된다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.1
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• pp.25-36
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• 2016

Heavy metals in the stream sediments around Shihwa Lake were studied not only to investigate the characteristics of spacio-temporal distribution but also to assess the pollution degree and ecological risk using various pollution indices. Among metals, Zn had the highest values (1,311 mg/kg) and Hg showed the lowest value (0.261 mg/kg). The order of mean concentrations (mg/kg) of metals was Zn>Cu>Pb>Cr>Ni>Co>As>Cd>Hg in stream sediments around Shihwa Lake. Metal concentrations showed different pollution pattern with industrial region, indicating that these metals originated from different sources and industrial region had higher metal concentration than rural/urban regions. The results of geoaccumulation index (Igeo) showed that the stream sediments were significantly polluted with Cd, Cu, Zn and Pb, indicating moderately to highly polluted by these metals. According to PLI consideration, industrial region was more seriously polluted by metals whereas an rural/urban region was not polluted. About 85% of sampling site for Cr, Ni, Cu, Zn and Pb from industrial regions were exceeded the PEL values. The mPELQ and SQI values derived from PEL of industrial region were classified as 'highly toxic' and 'very poor' and metal pollution level tend to be worse in wet season. This indicates that the industrial activities and stromwater runoff represents an important sources of heavy metals around Shihwa Lake.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.699-709
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• 2017

We measured the grain size, total organic carbon (TOC), total nitrogen (TN), and heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn) in order to understand the spatial distribution and pollution level of organic matter and metals in surface sediment around Goseong Bay, a shellfish farming area, Korea. The surface sediments were composed of finer sediments such as mud and clay. The concentration of TOC, TN, and heavy metals were much higher in the innermost bay than in the mouth and outside of bay. The spatial distribution of organic matter and heavy metals and C/N ratio (5-10) in sediment showed that the organic matter and heavy metals in sediment of the study region were significantly influenced by oceanic origin organic matter and anthropogenic sources, respectively. Based on the results of four assessment techniques (sediment quality guideline, geoaccumulation index, pollution load index, ecological risk index), the sediments around the Goseong Bay were a little polluted for heavy metals and the high metal concentrations in the northern region of bay could adverse impact on benthic organisms in sediment. Thus, the systematic management plan for the improvement of water and sediment environment and the concentrated monitoring of pollutants for sustainable aquaculture and seafood safety around Goseong Bay are necessary in the future.

• Journal of Ecology and Environment
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• v.33 no.2
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• pp.121-131
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• 2010

Betula platyphylla var. japonica and Betula ermanii segregate vertically at an elevation of approximately 1,850 m on Mt. Neko in Nagano Prefecture, Japan. B. platyphylla var. japonica and B. ermanii were the dominant species below and above this altitude, at which the mean-annual and growing-season air temperatures were $4^{\circ}C$ and $14.1^{\circ}C$, respectively. Based on a modification of Kira's warmth index which employs cumulative temperature represented as $^{\circ}C$ day, leaf unfolding in both species was observed to be initiated at $58^{\circ}C$ day and $169^{\circ}C$ day, respectively. In 1996, leaf unfolding was initiated on 18 May in B. platyphylla var. japonica (+/-6 days) and on 5 June in B. ermanii (+/-8 days), shortly after the last frost which occurred on 5 May 1995 above 1,850 m; below this elevation there was no risk of frost at the time. At elevations above 1,850 m, the unfolded leaves of B. platyphylla were damaged by late frost, while B. ermanii escaped injury because the leaves were still protected by winter buds. The optimum temperature for seed germination in both B. platyphylla and B. ermanii was $30^{\circ}C$. Temperature alternation from 10 to $30^{\circ}C$ and moist storage of seeds at $4^{\circ}C$ (stratification) prior to incubation increased germination rates in both species. The seedlings of B. ermanii had a greater survival rates than those of B. platyphylla var. japonica when planted above 1,850 m. Comparisons of the timing of leaf unfolding and the latest frost at a site appeared to be the main factors affecting the vertical distribution of these species.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.4
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• pp.510-520
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• 2021

To understand the status of organic matter and heavy metal pollution in surface sediment of a fish farming area, we have measured the concentrations of total organic carbon (TOC), total nitrogen (TN), and heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn) in surface sediments of a fish farming area near Tongyoung-Geoje coast. The mean concentrations of TOC and TN were 22.7 mg/g and 3.4 mg/g, respectively, and were much higher than those in surface sediments of a semi-enclosed bay in the southern coast of Korea. The mean concentrations of As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn were 10.5 mg/kg, 0.37 mg/kg, 82.9 mg/kg, 127 mg/kg, 4.19%, 0.041 mg/kg, 596 mg/kg, 39.5 mg/kg, and 175 mg/kg, respectively, and the mean concentrations of Cd and Cu were three times higher than those in surface sediments of shellfish farming area in the southeastern coast of Korea. In addition, the concentrations of TOC and corrected Cu exceeded the values of sediment quality guidelines applied in Korea, and pollution load index (PLI) and ecological risk index (ERI) showed that the metal concentrations in the sediments of some fish farming area have a strongly negative ecological impact on benthic organisms, although most metal concentrations did not exceed the sediment quality guidelines. Based on overall assessment results, the surface sediments of fish farming areas in the study region are polluted with organic matter and some heavy metals. Thus, a comprehensive management plan is necessary to improve the sedimentary environments, identify primary contamination sources, and reduce the input of pollution load for organic matter and heavy metals in the sediments of fish farming areas.

• Journal of Preventive Medicine and Public Health
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• v.51 no.1
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• pp.33-40
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• 2018

Objectives: The aim of this study was to determine the factors associated with the spatial distribution of the incidence of colorectal cancer (CRC) in the neighborhoods of Tehran, Iran using Bayesian spatial models. Methods: This ecological study was implemented in Tehran on the neighborhood level. Socioeconomic variables, risk factors, and health costs were extracted from the Equity Assessment Study conducted in Tehran. The data on CRC incidence were extracted from the Iranian population-based cancer registry. The $Besag-York-Molli{\acute{e}}$ (BYM) model was used to identify factors associated with the spatial distribution of CRC incidence. The software programs OpenBUGS version 3.2.3, ArcGIS 10.3, and GeoDa were used for the analysis. Results: The Moran index was statistically significant for all the variables studied (p<0.05). The BYM model showed that having a women head of household (median standardized incidence ratio [SIR], 1.63; 95% confidence interval [CI], 1.06 to 2.53), living in a rental house (median SIR, 0.82; 95% CI, 0.71 to 0.96), not consuming milk daily (median SIR, 0.71; 95% CI, 0.55 to 0.94) and having greater household health expenditures (median SIR, 1.34; 95% CI, 1.06 to 1.68) were associated with a statistically significant elevation in the SIR of CRC. The median (interquartile range) and mean (standard deviation) values of the SIR of CRC, with the inclusion of all the variables studied in the model, were 0.57 (1.01) and 1.05 (1.31), respectively. Conclusions: Inequality was found in the spatial distribution of CRC incidence in Tehran on the neighborhood level. Paying attention to this inequality and the factors associated with it may be useful for resource allocation and developing preventive strategies in at-risk areas.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.3
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• pp.124-131
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• 2012

This study was carried out to evaluate a possible change in freeze risk for 'Changhowon Hwangdo' peach buds in three major peach growing areas under the future climate projected by RCP8.5 emission scenario. Mean values of the monthly temperature data for the present decade (2000s) and the future decades (2020s, 2050s, 2080s) were extracted for farm lands in Icheon, Chungju, and Yeongcheon-Gyeongsan region at 1km resolution and 30 sets of daily temperature data were generated randomly by a stochastic process for each decade. The daily data were used to calculate a thermal time-based dormancy depth index which is closely related to the cold tolerance of peach buds. Combined with daily minimum temperature, dormancy depth can be used to estimate the potential risk of freezing damage on peach buds. When the freeze risk was calculated daily for the winter period (from 1 November to 15 March) in the present decade, Icheon and Chungju regions had high values across the whole period, but Yeongcheon-Gyeongsan regions had low values from mid-December to the end of January. In the future decades, the frequency of freezing damage would be reduced in all 3 regions and the reduction rate could be as high as 75 to 90% by 2080's. However, the severe class risk (over 80% damage) will not disappear in the future and most occurrences will be limited to December to early January according to the calculation. This phenomenon might be explained by shortened cold hardiness period caused by winter warming as well as sudden cold waves resulting from the higher inter-annual climate variability projected by the RCP8.5 scenario.