• Land and Housing Review
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• v.10 no.3
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• pp.17-22
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• 2019

In recent years, crime has been steadily increasing, causing not only economic damage but also aggravating the social atmosphere. The CPTED(Crime Prevention Through Environmental Design) guideline, which is an environmental crime prevention design technique, reduces the possibility of crime by implementing a proper defensive design plan through appropriate lighting design in the city and reduces the fear of crime. Among the various principles of CPTED, the proper use of street lamps and CCTV is considered to be an important factor in enabling natural surveillance. In this study, the authors identified and quantified the current status of the installation of street lamps and CCTV in each autonomous district of Seoul. The physical quantity of lighting and social factor quantified from light lamps and CCTV data, respectively, were expected to support the guidelines presented by CPTED. Therefore, we conducted statistical analysis based on quantified values and found that street lamps and CCTV had a statistically significant relationship with crime rate. In addition, the correlation between the safety index and the crime rate, calculated by dividing the number of street lamps and CCTVs by area, was also analyzed and an R2 value of 0.647 was confirmed.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.383-391
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• 2006

In Korea, the major source of serious air pollution is motor vehicles. Air pollution from vehicles has been annually increased. Then the government will try to control the vehicle emission by applying the effective emission management policy for the manufactured and in-used car. It is necessary to correctly calculate the emission factor for successful propulsion of the vehicle emission control policy. In this study, correlation analysis of exhaust emissions from vehicles between CVS-75 mode and Korea mode was conducted. A total of 25 light-duty buses were tested on the chassis dynamometer system in order to measure CO, HC, NOx PM and fuel efficiency (F.E.). For the test modes, 10 different Korea modes and CVS-75 mode were used. As the result of correlation analysis between those modes, most of the correlation coefficients were higher than 0.90. On the basis of high correlation between those modes, correction factors by driving conditions were estimated. Through the results of this study, we obtained essential basic data to correct difference from those modes.

• Membrane and Water Treatment
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• v.8 no.2
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• pp.137-147
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• 2017

A water treatment utility in South Korea operates a large system of pressurized hollow fiber membrane (PHFM) modules. The optimal selection of membrane module for the full scale plant was critical issue and carried out using Risk-based Life Cycle Cost (RbLCC) analysis based on the historical data of operation and maintenance. The RbLCC analysis was used in the process of decision-making for replacing aged modules. The initial purchasing cost and the value at risk during operation were considered together. The failure of modules occurs stochastically depending on the physical deterioration with usage over time. The life span of module was used as a factor for the failure of Poisson's probability model, which was used to obtain the probability of failure during the operation. The RbLCC was calculated by combining the initial cost and the value at risk without its warranty term. Additionally, the properties of membrane were considered to select the optimum product. Results showed that the module's life span in the system was ten years (120 month) with safety factor. The optimum product was selected from six candidates membrane for a full scale water treatment facility. This method could be used to make the optimum and rational decision for the operation of membrane water purification facility.

• Journal of Ecology and Environment
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• v.38 no.2
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• pp.145-156
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• 2015

This study was based on water quality data of the Lake Doam watershed, monitored from 2010 to 2013 at eight different sites with multiple physiochemical parameters. The dataset was divided into two sub-datasets, namely, non-rainy and rainy. Principal component analysis (PCA) and factor analysis (FA) techniques were applied to evaluate seasonal correlations of water quality parameters and extract the most significant parameters influencing stream water quality. The first five principal components identified by PCA techniques explained greater than 80% of the total variance for both datasets. PCA and FA results indicated that total nitrogen, nitrate nitrogen, total phosphorus, and dissolved inorganic phosphorus were the most significant parameters under the non-rainy condition. This indicates that organic and inorganic pollutants loads in the streams can be related to discharges from point sources (domestic discharges) and non-point sources (agriculture, forest) of pollution. During the rainy period, turbidity, suspended solids, nitrate nitrogen, and dissolved inorganic phosphorus were identified as the most significant parameters. Physical parameters, suspended solids, and turbidity, are related to soil erosion and runoff from the basin. Organic and inorganic pollutants during the rainy period can be linked to decayed matters, manure, and inorganic fertilizers used in farming. Thus, the results of this study suggest that principal component analysis techniques are useful for analysis and interpretation of data and identification of pollution factors, which are valuable for understanding seasonal variations in water quality for effective management.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.4
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• pp.1-9
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• 2010

In response to climate change under a university level, this study has intended to find carbon-neutral campus development measures for Chungbuk National University (CBNU), which is composed of such facilities as education, research, and residential buildings. To reach this goal, we reviewed related literatures to find development measures for carbon neutral campus, employed a survey method asking students to show their preference and suitability toward provided measures, and statistical analyses to find appropriate measures using factor analysis. We have found the following results. First, based on literature review, we have identified several concepts regarding carbon-neutral city and has found the elements of carbon-neutral campus development. Second, we have drawn carbon-neutral campus development measures of CBNU through factor analysis. Finally, based on the characteristics and the present carbon-neutral campus conditions of the CBNU, we presented development measures.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.21-31
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• 2020

Environmental pollution and climate change in Vietnam are now becoming a major concern. This situation is increasing the pressure on the companies to improve their social responsibility in production and business activities and disclose the environmental information to meet the requirements of stakeholders. This study investigates the internal and external factors of the company that affects the environmental information disclosure of listed companies on the Vietnam stock market as business sector, firm size, corporate manager perceptions, profitability, financial leverage, community pressure, pressures from stakeholders, government pressure influencing environmental information disclosure. Analytical data collected through the survey of 120 listed companies on the Ho Chi Minh City Stock Exchange (HOSE). By testing Cronbach's Alpha, exploratory factor analysis (EFA) and logistic regression analysis, the results of the study show that the level of environmental information disclosure of listed companies on the stock market in Vietnam depends heavily on government regulations, followed by the pressure from stakeholders, community pressure, views of business managers, companies size, business sector, and particularly profitability and financial leverage factors that have a negative relationship with environmental information disclosure.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.12a
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• pp.45-50
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• 2004

Indoor air quality can be affected by indoor sources, ventilation, decay and outdoor levels. Alt hough technologies exist to measure these factors, direct measurements are often difficult. The purpose of this study was to develop an alternative method to characterize indoor environmental factors by multiple indoor and outdoor measurements. Daily indoor and outdoor NO2 concentrations were measured for 30 consecutive days in 28 houses in Brisbane, Australia, and for 21 consecutive days in 37 houses in Seoul, Korea. Using a mass balance model and regression analysis, penetration factor (ventilation rate divided by the sum of ventilation rate and deposition constant) and source strength factor (source strength divided by the sum of ventilation rate and deposition constant) were calculated using multiple indoor and outdoor measurements. Subsequently, the ventilation rate and NO2 source strength were estimated. Geometric means of ventilation rate were 1.44 ACH in Brisbane, assuming a residential NO2 deposition constant of 1.05 hr-1, and 1.36 ACH in Seoul, with the measured residential NO2 deposition constant of 0.94 hr-1. Source strengths of N02 were 15.8 ${\pm}$ 18.2 ${\mu}$g/m3${\cdot}$hr and 44.7 ${\pm}$ 38.1 ${\mu}$g/m3${\cdot}$hr in Brisbane and Seoul, respectively. In conclusion, indoor environmental factors were effectively characterized by this method using multiple indoor and outdoor measurements.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.4
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• pp.271-276
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• 2014

The purpose of this study was to survey Suwon citizens over the age of 20 in order to provide basic data on the extent of coverage of the city's water reclamation system and to set guidelines for a policy on water reuse. The survey used a questionnaire with two fields, rainwater use and wastewater recycling, for analyzing factors that influenced water reuse. A factor analysis of 19 questionnaires gave a Cronbach's alpha coefficient greater than 0.4. Factors that influenced rainwater use were environmental protection, water charges, and the risk of climate change. Of the total explanatory power, the share of rainwater use and environmental protection was 39.7% and 28.1% respectively. Environmental protection (explanatory power 24.2%) had an effect on the explanatory power of wastewater reuse. When factors influencing wastewater recycling, like cost of recycling, water management policy, climate change, and suspension of tap water supply were included, the explanatory power of each of these factors went up by 4.3%, 2.8%, 3.3%, and 1.1%, respectively. For more effective wastewater recycling, a water management policy that factors in the above is required, along with a campaign to educate citizens on water management and environment conservation. Additionally, it may be necessary to improve the reliability and the quality of water supply.

• Journal of Environmental Impact Assessment
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• v.27 no.4
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• pp.353-366
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• 2018

The purpose of this study was assessment the quality of water by using the statistical analysis technique of the Water flow and water quality from January 2012 to December 2016 at the unit basin for total pollutant load management system (TPLMS) in the Imjin River. Water flow and water quality were monitored at an average of 8 day intervals, 11 parameters were used for correlation analysis, principal component analysis (PCA), factor analysis (FA), and cluster analysis (CA). The Hierarchical CA was classified into three according to the change of space, such as natural rivers, urban rivers, point with large influence of point pollution source, it was found that the type of contamination source the similarity of water quality affected the classification of cluster. Using one-way analysis of variance (ANOVA) and post-hoc Analysis, there were statistically significant differences between mean values among the clusters. Correlation analysis showed the correlation coefficient between $COD_{Mn}$ and TOC was 0.951 (p<0.01) and the correlation was statistically significantly higher. According to the result PCA and FA, 3 principal components can explaining 72% of the total variations in water quality characteristics and main factor was EC, $BOD_5$, $COD_{Mn}$, TN, TP and TOC indirect indicators of organic matter and nutrients were influenced. This study presented the regression equation obtained by applying the factor scores to the multiple linear regression analysis and concluded that the management Indirect indicators of organic matter and nutrients is important for water quality management in the Imjin River basin.

• Journal of Korean Society of Rural Planning
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• v.27 no.3
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• pp.35-46
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• 2021

Ecosystem services play a role in promoting sustainable development by contributing to human welfare. For sustainable development, a balance between supply and demand for ecosystem services must be made. In this regard, in this study, factor analysis was performed using the results of measuring ecosystem services for the supply of ecosystem services and national statistical data representing socio-economic factors for demand for ecosystem services The results of analysis for Gyeong-gi Province are as follows. The service supply based on the result of ecosystem services was divided into the mixed service provisioning as factor1, the food provisioning as factor2, and the P retention service provisioning area as factor3. As for the demand for services based on socio-economic factors, factor1 is divided into urbanized areas, factor2 is forest development area, and factor3 is agricultural activity development area. Local governments that maintain balance were evaluated as Pocheon, Yangpyeong, Icheon, Pyeongtaek, Goyang, Suwon, Gwangmyeong, and Osan, and imbalanced local governments appeared in Gimpo, Uiwang, Anseong, and Yeoju. A management plan to maintain the balance between supply and demand of ecosystem services was suggested. The analysis method and results of this study are expected to be applicable to various local governments through regional expansion.