• 한국환경과학회지
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• 제32권2호
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• pp.99-120
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• 2023

The community structure of benthic macroinvertebrates in Upo wetland was identified, and the biological water quality was evaluated. In addition, through statistical analysis of current and literature data, ecological changes over time were evaluated for each wetland. Benthos were quantitatively collected in March, June, and September of 2020 and 2021, and 4 phyla, 5 classes, 16 orders, 42 families, 81 species and 3,406 individuals were identified. In the functional feeding group of Upo wetland, predators were dominant with 34 species (45.95%) and 1,504 individuals (41.84%). In the habitual dwelling group, sprawlers and swimmers showed the highest proportion in the number of species and individuals. Average biological indices in Mokpo and Upo were the highest and lowest, respectively, and it is considered that Mokpo maintains the healthy ecosystem for benthic macroinvertebrates. Community stability was high in Upo, and other wetlands are thought to be stabilizing. The ecological score of benthic macroinvertebrate community is considered to be more suitable index among three biological water quality evaluation indices for the environmental evaluation of Upo wetland. The evaluation results on changes in environmental quality showed that Upo has stable ecosystem without significant change, Mokpo and Sajipo have significant increases in some indices.

• 유기물자원화
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• 제8권3호
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• pp.73-80
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• 2000

본 연구의 목적은 톱밥을 공극개량제로 사용한 음식쓰레기 퇴비화시 숙성도 지표의 적합성을 평가하는 것이었다. 실험에 사용된 재료는 평균조성의 음식쓰레기(G20)였으며 여기에 톱밥을 첨가하여 초기 C/N비를 각각 30(GS30)과 50(GS50)으로 조절하였다. 또한 톱밥과 과량의 곡류를 첨가하여 초기 C/N비를 30(GSC30)으로 조절한 실험도 병행하였다. 숙성도 평가에 이용된 항목은 유기물 감소율, 물용출액 TOC, 수용성 당함량, 부식도 지표, 부식질 흡광도비 등이었다. 실험결과 유기물 감소율은 과량의 톱밥이 첨가된 GS50을 제외한 나머지 음식 쓰레기에서 적합한 퇴비숙성도 판단지표였다. 물용출액 TOC는 퇴비화기간 동안 뚜렷이 감소한 후 숙성단계에서 완만히 감소하여 적합한 퇴비숙성도 판단지표였다. 수용성 당함량은 톱밥과 과량의 곡류가 첨가된 음식쓰레기의 경우 숙성도 지표로 고려할 수 있었다. 부식도 지표와 부식질 흡광도비의 경우 일부 음식물쓰레기에 적용가능한 것으로 판단되었으나 모든 대상 음식쓰레기에 적용하기에는 추가적인 연구가 필요하였다. 상관분석 결과 과량의 곡류가 포함되고 공극개량제로 톱밥이 첨가되어 C/N비가 30정도로 제어된 음식쓰레기의 숙성도 여부를 판정하기 위한 지표로는 유기물 감소율, 물용출액 TOC, 수용성 당함량 그리고 부식질 흡광도비 등이 추천되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.65-70
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• 2001

Six recycling plants have started operation for recycling scrap home appliances since the spring of 2000 in Taiwan. The performance of the plants has not yet been measured during the 18-month period. The performance measurement, however, can be looked in several aspects. Because of the nature of these recycling plants, at least three aspects, namely government (representing general public), appliance manufacturers and owners of the recycling plants themselves should be considered in the performance evaluation. This study proposes various performance indices categorized in four groups: profitability, recyclability, automation and environment. The indices are different from the productivity and cost measures that are used in conventional manufacturing plants. Performances of three existing plants in Taiwan are evaluated as illustrative examples to demonstrate the use of the proposed measures. The practical implications of the performance indices are also discussed.

• 한국환경보건학회지
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• 제42권2호
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• pp.85-91
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• 2016

Objectives: The objective of this study was to assess heat stress, compare heat stress indices, and evaluate the usefulness of wet bulb globe temperature (WBGT) among outdoor workers exposed to heat during the summer season. Methods: WBGT, dry temperature, and heat index were measured using WBGT measurers (QUESTemp 32 model and QUESTemp 34 model, QUEST, WI, USA) by industrial hygienists from August 27 to September 16, 2015. Heat stress indices were measured at the workplaces of a shipbuilder in Ulsan and a construction site in Daegu. The dry temperature observed by the Automated Synoptic Observing System (ASOS) of the Korea Meteorological Administration was also compared. Results: Dry temperature measured by WBGT is different from that by ASOS. The temperature obtained from ASOS was less than $33^{\circ}C$, above which point a heat wave is forecast by the Korea Meteorological Administration. A heat index above $32.8^{\circ}C$ as a moderate risk was not observed during measurement. WBGT was consistently higher than $22^{\circ}C$, above which the risk of heat-related illness is increased in unacclimated workers involved in work with a high metabolic rate. WBGT was sometimes higher than $28^{\circ}C$, above which the risk of heat-related illness is increased in acclimated workers involved in work with a moderate metabolic rate in September. Conclusion: According to the measurement of heat stress indices, WBGT was more sensitive than heat index and temperature. Thus, general measures to prevent heat-related diseases should be implemented in workplaces during the summer season according to WBGT.

• 대한원격탐사학회지
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• 제40권4호
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• pp.319-341
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• 2024

The utilization of multispectral imaging systems (MIS) in remote sensing has become crucial for large-scale agricultural operations, particularly for diagnosing plant health, monitoring crop growth, and estimating plant phenotypic traits through vegetation indices (VIs). However, environmental factors can significantly affect the accuracy of multispectral reflectance data, leading to potential errors in VIs and crop status assessments. This paper reviewed the complex interactions between environmental conditions and multispectral sensors emphasizing the importance of accounting for these factors to enhance the reliability of reflectance data in agricultural applications.An overview of the fundamentals of multispectral sensors and the operational principles behind vegetation index (VI) computation was reviewed. The review highlights the impact of environmental conditions, particularly solar zenith angle (SZA), on reflectance data quality. Higher SZA values increase cloud optical thickness and droplet concentration by 40-70%, affecting reflectance in the red (-0.01 to 0.02) and near-infrared (NIR) bands (-0.03 to 0.06), crucial for VI accuracy. An SZA of 45° is optimal for data collection, while atmospheric conditions, such as water vapor and aerosols, greatly influence reflectance data, affecting forest biomass estimates and agricultural assessments. During the COVID-19 lockdown,reduced atmospheric interference improved the accuracy of satellite image reflectance consistency. The NIR/Red edge ratio and water index emerged as the most stable indices, providing consistent measurements across different lighting conditions. Additionally, a simulated environment demonstrated that MIS surface reflectance can vary 10-20% with changes in aerosol optical thickness, 15-30% with water vapor levels, and up to 25% in NIR reflectance due to high wind speeds. Seasonal factors like temperature and humidity can cause up to a 15% change, highlighting the complexity of environmental impacts on remote sensing data. This review indicated the importance of precisely managing environmental factors to maintain the integrity of VIs calculations. Explaining the relationship between environmental variables and multispectral sensors offers valuable insights for optimizing the accuracy and reliability of remote sensing data in various agricultural applications.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권1호
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• pp.37-52
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• 2020

Sensitivity analysis of hydrodynamic and reaction parameters in conceptual model reflecting aquifer characteristics of Korea was performed to evaluate the uncertainty in the predicted concentrations. Among the hydrodynamic input parameters, both hydraulic conductivity (K_x) and hydraulic gradient (I) affected transport behaviors of contaminants, and resulted in same convergence concentrations with continuous injections of contaminant. However, longitudinal dispervisity (α_L) affected both transport behaviors and the convergence concentrations of contaminants. Compared to the hydrodynamic parameters, growth kinetic and degradation parameters (μ_m & K_c) more significantly affected both transport behaviors and the convergence concentrations of contaminants, indicating those parameters had higher sensitivity indices causing the uncertainties of model predictions. Considering that the sensitivity indices of both hydrodynamic and reaction parameters were a function of transport distance of groundwater, the parameters with higher sensitivity indices, a priori, need to be investigated using conceptual model reflecting site-specific aquifer characteristics before field investigation. After determining the parameters with higher sensitivity indices, the detail field investigations for the selected hydrodynamic and reaction parameters were warranted to reduce the uncertainties of model predictions.

• 한국수자원학회논문집
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• 제49권3호
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• pp.207-215
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• 2016

본 연구에서는 우리나라 강수 및 기온과 다양한 기상인자와의 교차상관관계 분석을 통해 대규모 기후변동이 우리나라에 어떠한 영향을 주는지를 분석하였다. 강수 및 기온자료의 경우 앞선 연구인 "경험적 모드분해법을 이용한 기상인자와 우리나라 강수 및 기온의 상관관계 분석 : I. 자료의 분해 및 특성분석"의 연구결과를 통해 주기성, 경향성에 따라 분해한 강수 및 기온자료의 내재모드함수를 사용하여, 자료의 변동이 심하고 잡음이 포함된 원 자료를 통한 상관관계 분석보다 좀 더 명확한 상관계수를 계산하였다. 이렇게 분해된 기상자료와 기상인자간의 교차상관관계 분석을 통해 그 시간차와 상관계수를 계산하여, 주기성과 경향성 측면에서 어떠한 상관관계가 있는지를 분석하였다. 그 결과 주기성 측면에서 엘니뇨현상에 의한 기후변동이 우리나라 기상현상과 밀접한 관련이 있으며, 경향성 측면에서 기후변화로 인한 해수면 온도 증가추세가 우리나라 기상현상과 밀접한 연관이 있음을 알 수 있었다.

• Safety and Health at Work
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• 제9권2호
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• pp.232-235
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• 2018

Background: This study was conducted to investigate the heat stress and semen quality among male workers in a steel industry in Iran and investigate the relationship between heat stress indices and semen parameters. Methods: The study was conducted on workers exposed (n = 30) and unexposed (n = 14) to heat in a steel industry. After obtaining a brief biography of the selected employees, scrotal temperature, oral temperature, and environmental parameters were measured, and their semen samples were analyzed according to the procedure recommended by the World Health Organization. The heat stress indices, including wet-bulb globe temperature (WBGT) and predicted heat strain (PHS), in their workplace were calculated according to environmental parameters (ISO 7243:1989 and 7933:2004, respectively). Results: Time-weighted averages of WBGT and PHS ($35.76^{\circ}C$ and 491.56 $w/m^2{\frac{w}{m^2}}$, respectively) for the exposed group were higher than threshold limit values. The mean difference of environmental, physiological, and semen parameters (exception: pH of semen), and also WBGT and PHS indices were statistically significant (p < 0.05) between the two groups. Mean semen parameters were in the normozoospermic range. WBGT and PHS indices showed significantly "negative" correlation with physiological parameters (scrotal and oral temperature) and most semen parameters (semen volume, sperm morphology, sperm motility, sperm count; p < 0.05); moreover, the correlation of WBGT with these parameters was stronger than PHS. Conclusion: Semen parameters of the studied workers exposed to heat were in the borderline level of normozoospermic range, and their semen parameters were significantly lower than controls. For better assessment of occupational environment concerning physiological and semen parameters in steel industries, WBGT can be a more useful index.

• 한국산림과학회지
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• 제95권6호
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• pp.696-704
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• 2006

본 연구는 광역지자체를 평가 단위로 하여 산림지속성 지수 도출을 목적으로 한다. 산림지속성은 지속가능발전의 세 개의 축인 경제, 사회, 환경과 함께 기반을 추기하여 네 개의 축(부문)에 근거하여 평가되었다. 이들 부문의 중요도는 계층분석법의 한 형태인 쌍대비교 방식에 의하여 도출하였다. 경제, 사회, 환경에 해당하는 지표는 각기 3개씩, 기반 부문에는 6개로, 총 15개의 지표를 이용하여 산림지속성 지수를 산출하였다. 지표의 가중치 적용 방법으로는 점수가중치 방법을 사용하였다. 산림지속성 지수는 1995년부터 2004년까지 자료를 토대로 부문별, 관리/건강성, 종합지수로 구분하여 산정하였다. 산림지속성 종합지수는 2004년 기준으로 경상북도가 71.8로 가장 높았으며 인천이 22.9로 가정 낮게 나타났다.

• Journal of Forest and Environmental Science
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• 제35권3호
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• pp.159-172
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• 2019

Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.