• 한국환경복원기술학회지
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• 제13권6호
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• pp.117-131
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• 2010

This study was conducted to utilize as basic information for the construction of conservation and estimation system for Palustrine wetland, which was badly managed and imprudently reclaimed, through the analysis of distribution characteristics and the estimation of conservation value for sample sites (eight wetlands) in rural area. As the result of wetland type classification, these wetlands was classified by 4 types (Permanent freshwater marshes/pools, ponds, Aquaculture ponds, and Seasonally flooded agricultural land) by Ramsar system, 3 types (Emergent Wetland, Aquatic Bed, and Scrub-Shrub Wetland) by NWI (Cowardin) System, 5 types (Farm Pond Depression, Under-flow wetland, Man-made Pond Depression, Abandoned Paddy Fields Wetland, and Reservoir Shore) by National Wetland's Categorical System, and 3 types (Aquatic Bed Wetland, Emergent Wetland, and Forested Wetland) by Lee (2000) System. These results suggest us developing the new type classification system for small Palustrine wetland in Korean rural areas. The score of function assessment (The Modified RAM) for small Palustrine wetlands was high at the wetlands nearby hills and rice paddy fields, and low at those nearby upper fields, which was mainly affected by land-use and vegetation. The functions as 'Flood/Storm Water Storage', 'Runoff Attenuation', 'Water Quality Protection' were resulted by the structural difference of inflow and outlet. Some functions as 'Wetland size', 'Wetland to immediate watershed ratio', 'Presence of boat traffic', 'Maximum water depth', 'Fetch of water's body' of RAM were not appropriate in evaluation of small wetlands in rural area. Which suggest us developing the new function assessment system for small Palustirne wetland in Korean rural areas.

• 환경영향평가
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• 제20권6호
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• pp.797-813
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• 2011

Frequently occurring flood and drought due to abnormal climate and global warming have increased the necessity of an effective water resources control and management of river flows. The various hydraulic structures are constructed in river as part of an effective water resources management. It is very important to analyse characteristics of flow according to installing hydraulic structures in this situations. The objective of this study is to investigate the hydraulic behaviors of flow considering affections of hydraulic structures using 2-D numerical model. To do this, both RMA-2 model and developed RAM2 model are used to analyse flow phenomena before and after installation of hydraulic structures in Nakdong river. As a result of, the water surface elevation at upstream regions increased about 22cm~66cm and the velocity around the structures sharply increased after installation of structures. The measures for the rise of water surface at upstream and local scour due to high velocity around the structures must be established when the structures is constructed.

• 해양환경안전학회지
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• 제29권1호
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• pp.76-85
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• 2023

신재생에너지로서 수소에 대한 수요가 증가하고 있으나 기존의 화석 연료와 달리 수소는 연료 공급을 위한 전용 충전소가 필요하며, 이러한 인프라 확보를 위해서 수소충전소의 위험성 평가가 선행되어야 한다. 따라서 본 연구에서는 정성적 위험성평가와 정량적 위험성 평가로 구분하여 수소충전소에 대한 위험성평가를 수행하였다. 정성적 평가는 Hazard and Operability Analysis(HAZOP) 기법을 사용하여 Dispenser Module을 두 개의 Node로 평가하였으며, Criticality Estimation Matrix에 따라 Filter의 막힘으로 인한 사고와 고압 사고의 위험도가 High Level로 평가되었다. 정량적 위험성 평가는 Hydrogen Korea Risk Assessment Module(Hy-KoRAM)을 사용하여 화재의 형상과 피해영향범위를 나타냈고, 개인적 위험도와 사회적 위험도에 대한 평가를 수행하였다. 개인적 위험도는 수소충전소로부터 약 100m 떨어진 공공시설 부근까지 추가적인 안전조치가 고려되는 As Low As Reasonably Practicable(ALARP) 구간의 위험도를 보였고, 사회적 위험도 역시 약 10명의 사망자가 발생할 사고빈도가 1E-04/year로 도출되며 ALARP 구간 내에 나타났다. 정성적·정량적 위험성 평가 결과, 공정 단계의 추가적인 안전 조치와 수소충전소 부근의 제한구역 설정을 통하여 안전성 향상 방안을 제시하였다.

• Journal of Chest Surgery
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• 제53권6호
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• pp.392-399
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• 2020

Background: Surgical treatment of empyema thoracis in patients with chronic kidney disease is challenging, and few studies in the literature have evaluated this issue. In this study, we aim to report the surgical outcomes of empyema and to analyze factors predicting perioperative mortality in patients with chronic kidney disease. Methods: This retrospective study included data from 34 patients with chronic kidney disease (estimated glomerular filtration rate <60 mL/min/1.73 ㎡ for 3 or more months) who underwent surgery for empyema between 2012 and 2020. An analysis of demographic characteristics and perioperative variables, including complications, was carried out. Postoperative mortality was the primary outcome measure. Results: Patients' age ranged from 20 to 74 years with a 29-to-5 male-female ratio. The majority (n=19, 55.9%) of patients were in end-stage renal disease (ESRD) requiring maintenance hemodialysis. The mean operative time was 304 minutes and the mean intraoperative blood loss was 562 mL. Postoperative morbidity was observed in 70.5% of patients (n=24). In the subgroup analysis, higher values for operative time, blood loss, intensive care unit stay, and complications were found in ESRD patients. The mortality rate was 38.2% (n=13). In the univariate and multivariate analyses, poor performance status (Eastern Cooperative Oncology Group >2) (p=0.03), ESRD (p=0.02), and late referral (>8 weeks) (p<0.001) significantly affected mortality. Conclusion: ESRD, late referral, and poor functional status were poor prognostic factors predicting postoperative mortality. The decision of surgery should be cautiously assessed given the very high risk of perioperative morbidity and mortality in these patients.

• 농업과학연구
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• 제50권4호
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• pp.675-696
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• 2023

Terpenoids, also referred to as terpenes, are a large family of naturally occurring chemical compounds present in the essential oils extracted from medicinal plants. In this study, a nondestructive methodology was created by combining ATR-FT-IR (attenuated total reflectance-Fourier transform infrared), and Raman spectroscopy for the terpenoids assessment in medicinal plants essential oils from ten different geographical locations. Partial least squares regression (PLSR) and support vector regression (SVR) were used as machine learning methodologies. However, a deep learning based model called as one-dimensional convolutional neural network (1D CNN) were also developed for models comparison. With a correlation coefficient (R²) of 0.999 and a lowest RMSEP (root mean squared error of prediction) of 0.006% for the prediction datasets, the SVR model created for FT-IR spectral data outperformed both the PLSR and 1 D CNN models. On the other hand, for the classification of essential oils derived from plants collected from various geographical regions, the created SVM (support vector machine) classification model for Raman spectroscopic data obtained an overall classification accuracy of 0.997% which was superior than the FT-IR (0.986%) data. Based on the results we propose that FT-IR spectroscopy, when coupled with the SVR model, has a significant potential for the non-destructive identification of terpenoids in essential oils compared with destructive chemical analysis methods.

• 한국가스학회지
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• 제25권4호
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• pp.57-62
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• 2021

본 연구는 국제공동 연구로 개발 된 HyKoRAM 프로그램을 이용하여 저장설비(튜브트레일러)의 누출 시 위험성평가를 진행하였다. 수소충전소 내의 고압가스설비는 크게 4가지로 저장설비(튜브트레일러), 처리설비(압축기), 압축가스설비, 충전설비(디스펜서)로 분류된다. 그 중 저장설비인 튜브트레일러의 설계 사양, 주변 환경 조건 등을 반영하여 기존에 발생된 사고 및 잠재적 사고 위험 사고 시나리오를 구성하였다. 이를 통해, 수소충전소 저장 설비의 위험을 확인하고 수소충전소 안전성 향상을 위한 대책을 제안한다.

• 한국환경복원기술학회지
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• 제24권1호
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• pp.15-24
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• 2021

This study was carried out to propose the functional assessment and a wise use strategy on the ecologically valuable 'village wetlands' distributed in living area in Geumsan gun, Chungnam province, Korea. The targets of the functional evaluation were 24 wetlands, selected from 123 village wetlands, where villages and agricultural lands or core ecosystems are located within living area near the wetland and wetlands with historical and cultural significance. The functional evaluation was carried out by RAM (Rapid Assessment Model) and the conservation strategies were suggested. As a result of the functional evaluation, 9 wetlands were rated 'high' (2 'absolute conservation' and 7 'conservation' strategies), 14 wetlands were rated 'medium' ('enhancement' strategies), and one wetland was rated 'low' ('restore or enhancement' strategy). In consideration of the results of the functional evaluation, interviews with village residents, and historic meaning, 6 important village wetlands were selected that require additional management strategies, such as conservation, enhancement, and restoration. 2 wetlands were from "absolute conservation" strategy and 4 wetlands derived from "conservation" and "enhancement" strategy wetlands in consideration of the ecological connectivity of wetlands, the use of surrounding land, and the function as a biological habitat. The wise use and conservation strategy was specifically proposed respectively.

• 한국가스학회지
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• 제24권6호
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• pp.83-90
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• 2020

본 연구는 국제공동 연구로 만들어진 HyKoRAM 프로그램을 이용하여 위험성평가를 진행하였다. 수소충전소 내 압축기, 저장탱크, 수소 배관 등 주요 시설 및 구성품의 설계 사양, 실증 단지 주변의 환경 조건 등을 반영한 대안의 사고 시나리오와 시설에서 발생할 수 있는 최악의 시나리오에 기반하여 위험성 평가를 실시하였다. 수소충전소의 잠재 위험을 확인하여 수소 저장 탱크, 처리 시설, 저장 시설 등에서 발생 가능한 최악의 누출, 화재, 폭발, 사고 시나리오를 도출하고, 사고 발생 가능성과 인체, 주변 시설 피해 영향 분석을 하여 안전성을 검토하고자 한다.

• 한국환경과학회지
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• 제25권11호
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• pp.1521-1530
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• 2016

As a result of dividing typhoon that affected Korean Peninsular between 1999 and 2012 into 7 types of path and entering forecast field and analysis field of RDAPS, until 36 hours from the time of forecast, it is reliable to use the forecast field of RDAPS to predict typhoon and for each typhoon path, the difference between the forecast and the analysis shows normal distribution, which is usable for weather forecast until the $36^{th}$ hour. In the $48^{th}$ hour from the time of forecast, the difference of result depending on each typhoon path increased, which was analyzed to be due to errors in the forecast. It was expected that relatively reasonable results should be shown if the $36^{th}$ hour forecast is used to predict the strength and distribution of strong wind. As a result of using Korean RAM and observing the difference of the maximum damage, reliability was secured up to 36 hours and after 48hours, it was expected that the fluctuation of results may become more severe.

• 공업화학
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• 제34권1호
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• pp.75-79
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• 2023

The International Maritime Organization (IMO) Marine Environmental Protection Committee (MEPC) may adopt actions after completing impact assessments and reviewing results in accordance with the original strategy and impact assessment procedure (MEPC.1/Circ.885). The assessment of the impact of greenhouse gas (GHG) reduction measures is an important step in determining whether to implement GHG regulations. This study identifies and proposes improvements in the impact assessment procedure for future mid- and long-term measures. Improvements for future measures should start with a review of "the procedure for assessing impacts on states of candidate measures" and "the actual process of the comprehensive impact assessment for short-term measures in 2021." The procedural improvements were largely derived from the order and period of task performance, the clear definition of terms, and the review of task results through lessons learned, analysis, and expert workshops. The impact assessment of future mid- and long-term measures should be procedurally improved to ensure uniformity and consistency, which will provide objective results for Member States and industries to help smooth the adoption of measures.