• 한국환경과학회지
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• 제26권4호
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• pp.483-491
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• 2017

This study provides basic data for the cost operating strategy of forest welfare infra facilities. We use the Price-Sensitivity Measurement technique (PSM) for a forest welfare infra facility (healing forest, wood camping, forest leisure sport, etc.). In addition, we conduct a survey in the four target locations (Kyung-gi, Kyung-sang, Chung-cheong, and Jeolla) and receive answer from 390. The results show that higher the price of present infra facilities, higher the price sensibility. The forest welfare infra facilities we include are healing forest 1,894 won, wood camping 5,625 won, mtb park 9,530 won, mountain horseback riding 14,556 won, paragliding 20,252 won, mountain ski 3,075won. However, we investigate zip-lines at lower than current price levels.

• Computers and Concrete
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• 제33권4호
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• pp.409-423
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• 2024

Using an extensive database, a sensitivity analysis across fifteen machine learning (ML) classifiers was conducted to evaluate the impact of various data manipulation techniques, evaluation metrics, and explainability tools. The results of this sensitivity analysis reveal that the examined models can achieve an accuracy ranging from 72-93% in predicting the fire-induced spalling of concrete and denote the light gradient boosting machine, extreme gradient boosting, and random forest algorithms as the best-performing models. Among such models, the six key factors influencing spalling were maximum exposure temperature, heating rate, compressive strength of concrete, moisture content, silica fume content, and the quantity of polypropylene fiber. Our analysis also documents some conflicting results observed with the deep learning model. As such, this study highlights the necessity of selecting suitable models and carefully evaluating the presence of possible outcome biases.

• 한국환경교육학회:학술대회논문집
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• 한국환경교육학회 2004년도 후반기 정기 학술발표대회
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• pp.153-161
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• 2004

• 한국환경보건학회지
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• 제46권2호
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• pp.136-149
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• 2020

Objectives: The purpose of this study was to perform an aggregate human risk assessment for benzene in an industrial complex using the CalTOX model and to improve the reliability and predictability of the model by analyzing the uncertainty and sensitivity of the predicted assessment results. Methods: The CalTOX^TM 4.0 beta model was used to evaluate a selected region, and @Risk 7.6 software was used to analyze uncertainty and sensitivity. Results: As a result of performing the aggregate risk assessment on the assumption that 6.45E+04 g/d of benzene would be emitted into the atmosphere over two decades, 3% of the daily source term to air remained in the selected region, and 97% (6.26E+04 g/d) moved out of the region. As for exposure by breathing, the predicted LADD_inhalation was 2.14E-04 mg/kg-d, and that was assessed as making a 99.99% contribution to the LADD_total. Regarding human Risk_cancer assessment, the predicted human cancer risk was 5.19E-06 (95% CI; 4.07E-06-6.81E-06) (in the 95th percentile corresponding to the highest exposure level, a confidence interval of 90%). As a result of analyzing sensitivity, 'source term to air' was identified as the most influential variable, followed by 'exposure time, active indoors (h/day)', and 'exposure duration (years)'. Conclusions: As for the results of the human cancer risk assessment for the selected region, the predicted human cancer risk was 5.19E-06 (95% CI; 4.07E-06-6.81E-06) (in the 95th percentile, corresponding to the highest exposure level, a confidence interval of 90%). As a result of analyzing sensitivity, 'source term to air' was found to be most influential.

• 한국초등과학교육학회지:초등과학교육
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• 제41권3호
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• pp.468-479
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• 2022

본 연구에서는 인공지능 기반 도구를 활용한 미세먼지 환경교육 프로그램을 개발하고 초등학생들에게 적용하여 환경감수성과 자기효능감에 미치는 영향을 알아보고자 하였다. 이를 위하여 초등학교 6학년 학생 29명을 대상으로 연구를 실시하였으며, 환경감수성과 자기효능감에 관한 사전⋅사후 검사 결과를 분석하였다. 본 연구의 결과는 다음과 같다. 첫째, 인공지능 기반 도구를 활용한 미세먼지 환경교육 프로그램은 초등학생들의 환경감수성 향상에 효과적이다. 둘째, 인공지능 기반 도구를 활용한 미세먼지 환경교육 프로그램은 초등학생들의 자기효능감 향상에 긍정적인 영향을 끼쳤다. 셋째, 인공지능 기반 도구를 활용한 미세먼지 환경교육 프로그램은 초등학생들의 환경에 대한 인식변화에 긍정적인 영향을 끼쳤다. 학생들은 프로그램을 적용한 후 미세먼지뿐만 아니라 환경에 관심을 많이 가지게 되었고, 일상생활과 연계하여 환경보호 실천 의식을 가지게 되었다. 이와 같이 인공지능 기반 도구를 활용한 미세먼지 환경교육 프로그램은 초등학생들의 환경감수성 및 자기효능감에 긍정적인 영향을 준 것으로 판단된다.

• 한국환경보건학회지
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• 제40권5호
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• pp.355-366
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• 2014

Objectives: This study seeks to evaluate the vulnerability assessment of the human health sector for $PM_{10}$, which is reflected in the regional characteristics and related disease mortality rates for $PM_{10}$ in Busan over the period of 2006-2010. Methods: According to the vulnerability concept suggested by the Intergovernmental Panel on Climate Change (IPCC), vulnerability to $PM_{10}$ is comprised of the categories of exposure, sensitivity, and adaptive capacity. The indexes of the exposure and sensitivity categories indicate positive effects, while the adaptive capacity index indicates a negative effect on vulnerability to $PM_{10}$. Variables of each category were standardized by the rescaling method, and each regional relative vulnerability was computed through the vulnerability index calculation formula. Results: The regions with a high exposure index are Jung-Gu (transportation region) and Saha-Gu (industrial region). Major factors determining the exposure index are the $PM_{10}$ concentration, days of $PM_{10}{\geq}50$, ${\mu}g/m^3$, and $PM_{10}$ emissions. The regions that show a high sensitivity index are urban and rural regions; these commonly have a high mortality rate for related disease and vulnerable populations. The regions that have a high adaptive capacity index are Jung-Gu, Gangseo-Gu, and Busanjin-Gu, all of which have a high level of economic/welfare/health care factors. The high-vulnerability synthesis of the exposure, sensitivity, and adaptive capacity indexes show that Dong-Gu and Seo-Gu have a risk for $PM_{10}$ potential effects and a low adaptive capacity. Conclusions: This study presents the vulnerability index to $PM_{10}$ through a relative comparison using quantitative evaluation to draw regional priorities. Therefore, it provides basic data to reflect environmental health influences in favor of an adaptive policy limiting damage to human health caused by vulnerability to $PM_{10}$.

• 폴리머
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• 제39권3호
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• pp.359-364
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• 2015

A self-oscillating interpenetrating polymer network (IPN) poly(acrylic acid)/poly(ethylene glycol) (PAA/PEG) hydrogel was prepared by using radical polymerization with a two-step method. The IPN hydrogel was characterized by FTIR spectroscopy and morphological analysis. The results indicated that the chains of PEG and PAA twined to form porous structure which is beneficial to water molecules entering inside of the hydrogel. In addition, the pH-responsive behavior, salt sensitivity, swelling/de-swelling oscillatory behaviors and self-oscillation in a closed pH oscillator were also studied. The results showed that the prepared hydrogel exhibited pH-sensitivity, good swelling/de-swelling reversibility and excellent salt sensitivity. The self-oscillating behavior of swelling/de-swelling for the prepared hydrogel was caused by pH alteration coupled with the external media. This study may create a new possibility as biomaterial including new self-walking actuators and other related devices.

• 한국환경과학회지
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• 제19권10호
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• pp.1219-1227
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• 2010

In this study, the sensitivity analysis of bed changes due to the various sediment transport equations have been conducted for 80 km reach of the Lower Nakdong River using the HEC-6 which is one dimensional numerical model. The bed elevation changes according to the different sediment transport formulas were compared and analyzed quantitatively. As a result of the numerical simulation, the final bed elevation calculated by Engelund and Hansen(1967), Ackers and White(1973), and Yang(1979) formulas was similar to one another in configuration. The bed change simulated by Engelund and Hansen(1967) were greatest among them, for example, 5.5 m deposition and 2.9 m erosion for 100 years. Also, in the case of Toffaleti (1969) equation, the maximum bed deposition of 8.04 m after 100 years was induced at the 73 km location upstream of the Nakdong River Estuary Barrage. Meyer-Peter-M$\ddot{u}$ller(1948) and Wilcock(2001) formulas produced the deposition only at the upstream end and there was little bed change in the downstream area. The unreal bed configuration of continuously up and down pattern was simulated by Laursen(1958) transport equation.

• 한국환경교육학회지:환경교육
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• 제16권2호
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• pp.15-28
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• 2003

In effort to help vitalize environmental education which is the most efficient way to preserve environment and solve environmental problems and also to provide necessary basic data, this research was conducted on the primary and secondary school teachers in Daegu for their awareness of the elements of environmental education, for their interests in environment and environmental issues, for their sensitivity on the seriousness of the environmental issues and for their knowledge of environmental vocabulary. Followings are the results: 1. 96% of the teachers supported the necessity of school education on environment, but only 51% went for adopting environment as an independent subject. 2. The majority of 57% said that they came to recognize environment and environmental issues 'through media such as TV and radio'. For the desirable form of environmental education, 64% supported 'field study or experience activity'. As for the undermining factors, the majority of 50% cited 'excessive focus of school education on college entrance' and 29% 'limitations of class hours'. 3. With regard to their interests in environment and environmental issues, they were between 3.43～4.08 point range out of 5 points. For their sensitivity about the seriousness of environment and environmental problems, the survey showed the range of 3.49～4.28 points out of 5 points. 4. There was no remarkable difference in the level of recognition between male and female teacher. But, according to disparity of age, teachers who are in their forties and fifties recognized better than teachers in twenties and thirties. Also, there was a striking difference among primary school, middle school, and high school teachers. High school teachers had the highest recognition level, while, middle school teachers had the lowest recognition level.

• 한국환경과학회지
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• 제19권2호
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• pp.125-136
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• 2010

The most important factors relating to the indoor air environment are temperature, airflow, humidity, and contaminant concentration. A sensitivity analysis of indoor environment factors was carried out to grasp influences along with changes of atmospheric conditions. An integrated multizone model was used to predict these sensitivities. This model was applied to an apartment with six zones. Airflow rates are influenced very seriously by changes of wind direct or wind velocity, but are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air temperatures are influenced very directly by changes of outdoor air temperature, but are influenced very slightly by wind direction or wind velocity and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air humidities are influenced very directly by changes of outdoor air humidity, but are not influenced at all by changes of outdoor air contaminant concentration and have little or no influence by changes of wind direction, wind velocity, or outdoor air temperature. Indoor air contaminant concentrations are influenced very seriously by changes of wind direct or wind velocity, but are influenced somewhat by changes of outdoor air contaminant concentration and are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity.