• The Journal of Engineering Geology
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• v.17 no.4
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• pp.545-554
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• 2007

Landslides is mainly induced by a heavy rainfall, earthquake ground motion, and some other factors like soil mechanics, morphological-geological factors etc. Since the starting point of the failure seemed to be originated at a construction site in the study, it is meaningful to find out the relationship between the landslide and the construction. For this study, the slope failure factor was examined carefully to see that the original natural slope had vulnerability and that the complex ground had unstability changed by construction. A field survey was conducted on the original ground surface and filled-up ground. A laboratory test was also conducted to determine the geomechanical properties of soil samples. 2D and 3D limit equilibrium analysis with changing groundwater level were conducted at the failure depth using a seismic refraction survey. The result shows that the factor of safety is similar stability under all condition, but unstable under saturated condition.

• Journal of Korean Society on Water Environment
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• v.33 no.5
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• pp.587-599
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• 2017

Physical environmental factors (water depth, current velocity and substrate) and fish community were surveyed in the Gapyeong stream, Korea. The fish group of Gapyeong Stream was divided into three types. Lithophilic fish, Koreocobitis rotundicaudata and Pseudopungtungia tenuicorpa preferred shallow depth, low-velocity current, and coarse bed condition, whereas Coreoleuciscus splendidus and Microphysogobio longidorsalis were adapted to high-velocity current and bed materials. Nektonic fish, Zacco koreanus and Zacco platypus appeared in a wide range of physical conditions. Intermediate fish, Hemibarbus longirostris, Pungtungia herzi and Coreoperca herzi adapted to moderate water depths and current velocities. Among them, H. longirostris and C. herzi were adapt to various bed materials. C. splendidus, M. longidorsalis and P. herzi showed high niche overlap for current velocity, water depth and substrate with Z. koreanus and Z. platypus. The occurrence of M. longidorsalis in a relatively low-velocity current compared to Z. koreanus and Z. platypus suggests that the current velocity act as a isolation factor for these species. The competition, isolation and character displacement among these species investigated detail in the future. Based on canonical correspondence analysis, the relative importance of each environmental factor was determined as substrate > water depth > current velocity.

• Asian Journal of Atmospheric Environment
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• v.6 no.1
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• pp.1-13
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• 2012

To identify the primary factor affected the decreased $PM_{10}$ concentration in Seoul which is the capital city of Korea, wind speed and emissions in 2003 and 2004 were analyzed. The level of air pollution is intense in Seoul and continually increased since the late 1990s. However the concentration of $PM_{10}$ has been greatly declined recently. In particular, the concentration of $PM_{10}$ decreased 14% in 2003 and 2004 excluding the Asian dust periods. It is suggested that the major factors for the decrease are differences in wind speed between the two years and the period of constant breeze. In 2003, intense Asian dust events happened frequently and it increased the concentration of total $PM_{10}$. The intense dust events were influence by the speed and duration of the wind. It is considered that the meteorological condition was the primary drive for the change of the concentration of $PM_{10}$. The decreased emissions seem to be the additional factor for the change in the concentration of $PM_{10}$.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.89-101
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• 2022

The study was conducted in Erhe Park, a neighborhood park in Dali City, China, to derive the influence of environmental factors in the park on the elderly's satisfaction and to analyze the satisfaction in order to provide improvement recommendations. First, the evaluation indicators were selected, by referencing previous research into the elderly's evaluation of external spatial environments and the influence of various factors was determined from the questionnaire and factor analysis. Second, a fuzzy comprehensive evaluation was conducted to understand the satisfaction of the elderly, and then an Importance-Performance Analysis(IPA) analysis was conducted to develop improvement recommendations. Results of the factor analysis showed that park's environmental factors were grouped into four categories: facility suitability and comfort, safety and convenience of use, natural environment comfort, and parkway convenience. Based on this, the overall satisfaction rating for the environmental factors in Erhe Park was between satisfactory and average. The natural environment comfort was rated satisfactory, the facility suitability and comfort, and convenience and safety were rated average, and parkway convenience was rated near to satisfaction. The IPA analysis revealed that the suitability of rest facilities, suitability of convenience facilities, facility management status, safety of entrances and exits, and nighttime lighting facilities were items of high importance but low satisfaction that needed to be improved. The results of this study can be utilized as a guide for future building or readjustment of senior-friendly parks, and they are critical for increasing senior-friendly park satisfaction.

• Earthquakes and Structures
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• v.19 no.3
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• pp.197-214
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• 2020

Diagrid structures have been introduced as a fairly modern lateral load-resisting system in the design of high-rise buildings. In this paper, a novel diagrid system called tube-in-tube diagrid building is introduced and assessed through pushover and incremental dynamic analyses. The main objectives of this paper are to find the optimum angle of interior and exterior diagrid tube and evaluate the efficiency of diagrid core on the probability of collapse comparing to the conventional diagrid system. Finally, the seismic performance factors of the proposed system are validated according to the FEMA P695 methodology. To achieve these, 36-story diagrid buildings with various external and internal diagonal angles are designed and then 3-D nonlinear models of these structures developed in PERFORM-3D. The results show that weight of steel material highly depends on diagonal angle of exterior tube. Adding diagrid core generally increases the over-strength factor and collapse margin ratio of tall diagrid buildings confirming high seismic safety margin for tube-in-tube diagrid buildings under severe excitations. Collapse probabilities of both structural systems under MCE records are less than 10%. Finally, response modification factor of 3.0 and over-strength factor of 2.0 and 2.5 are proposed for design of typical diagrid and tube-in-tube diagrid buildings, respectively.

• Journal of Environmental Science International
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• v.21 no.11
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• pp.1339-1348
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• 2012

The versatile aerosol concentration enrichment system (VACES) have proven useful for providing elevated levels of atmospheric aerosol to human and animal exposures. In this study, we describe a VACES and tests conducted to both optimize the enhancement factor (EF) and characterize how it depends on experiment conditions. Particle number concentrations were measured from upstream and downstream of the system by scanning mobility particle sizer (SMPS) with a long differential mobility analyzer (DMA) in combination with a condensation particle counter (CPC). SMPS was used for to determine VACES particle EF. Particle EF tends to increase for higher the saturator temperature ($T_{Sat}$) and lower the condenser temperature ($T_{Con}$). $T_{Con}$ higher than $0^{\circ}C$ and $T_{Sat}$ lower than $50^{\circ}C$ was the best to obtain the most increase in particle concentration. Correlation analysis of EF with factor variables of $T_{Sat}$ and $T_{Con}$ resulted in correlation 0.662 and 0.416, respectively. With all five predictor variables included in a multiple regression model, the EF had a liner correlation with $R^2=0.643$.

• Journal of The Korea Institute of Healthcare Architecture
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• v.17 no.1
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• pp.15-22
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• 2011

Nowadays, a proportion of healthcare service for the elderly has been improved due to the factors, such as a prolonged life expectancy, a growth of aging population and a change of member of family. For these factors, it is necessary for the elderly to receive treatment for multidisciplinary diseases, associated with psychological care of sociological concept. It is quite difficult in an acute-care hospital to accommodate the elderly patient because of the fact that an acute-care hospital is required to maintain a high level of medical care and technical standard. That is why specialized medical service is needed for the elderly. In the case of Germany, they are at the stage of the change from large scale facilities to specialized facilities applying the integrated concept. This paper addresses the medical environmental factor and distinction of medical facilities for the elderly through survey and analysis relating to all change in Germany. Therefore, it aims to suggest a fundamental resource for architectural planning and network of medical facilities for the elderly.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.741-749
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• 2008

Many small-scale ponds that serve as ecological habitat, recreation and irrigation are faced to eutrophication problem, which causes aesthetic nuisance and ultimately loss of their functions. Thus accurate evaluation of the trophic state of these ponds is essential to provide rational information to the stakeholders so that they can develop effective management actions. In this study, the trophic state of a small pond (Wonheung) that experiencing water quality degradation due to vicinity land development was assessed using various Trophic State Indexes (TSIs) and statistical analysis including Principal Components Analysis (PCA) based on the field monitoring data obtained from May to December, 2007. The results showed that the pond is under eutrophic state with average total nitrogen (T-N) and total phosphorus (T-P) concentrations of $708.1{\mu}g/L$ and $59.3{\mu}g/L$, respectively. The factor loading plot obtained from PCA showed distinct two influencing factors, PC 1 and PC 2. PC 1 was grouped by T-P, Chlorophyll a (Chl-a), suspended solids (SS), TN/TP ratio, and transparency that all strongly related to the eutrophication state, while PC 2 by temperature, conductivity, dissolved oxygen (DO) and turbidity that explains the seasonal water quality variations. The limiting factor was identified as light rather than phosphorus by both T-N/T-P ratio and TSI indexes analysis. The results and methodology adopted in this study can be used for water quality assessment for other small ponds and lakes.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.435-445
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• 2012

The aim of this study is to understand the characteristics of volatile oranic compounds (VOCs) and provide information about the present Indoor Air Quality (IAQ) at residential apartments. All samples were collected in 60-min interval using the tenax absorption trap between May, 2011 and February, 2012. And the effects of environmental factors such as temperature, humidity and construction characteristics were analyzed in relation to the measured concentrations. The results of this study showed that the mean concentration of VOCs was lower than the Ministry of the Environment's standards for maintenance of indoor air quality. The correlation analysis showed that ethylbenzene and xylene (r=0.916, p<0.01), toluene and ehtylbenzene (r=0.810, p<0.01), toluene and xylene (r=0.803, p<0.01) and toluene and styrene (r=0.588, p<0.01) were significant. The result of regression analysis was found that the influenece factors associated with the concentration of VOCs were the age and location of the apartment, remodeling, the temperature and the season.

• Journal of Forest and Environmental Science
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• v.36 no.2
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• pp.163-172
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• 2020

The objective of this study was to develop evaluation criteria for forest education using the Context, Input, Process, and Product (CIPP) model. To this end, we designed a survey based on expert advice and content analysis of previous studies on the CIPP model and forest education. The survey was conducted on 393 forest education specialists, and Cronbach's α coefficient was set as 0.6 or higher to verify reliability and validity, and to determine reliability by factor. Eventually, 52 out of 57 evaluation items were extracted, and the evaluation indexes were selected through factor analysis as follows: four evaluation indexes for the context dimension, namely "Clarity of goal setting," "Developing conditions for education," "Meeting of requirements," and "Institutional drive"; three evaluation indexes for the input dimension, namely "Acquisition of education infrastructure," "Establishment of operational support," and "Adequacy of assigned manpower"; four evaluation indexes for the process dimension, which were "Adequacy of budget allocation," "Expertise of forest education instructors," "Diversity of programs," and "Public-private academic partnership"; and five evaluation indexes for the product dimension, namely "Effectiveness of perception change," "Influence over the society," "Continuity of improvement in evaluation," "Continuity of education," and "Verification of the effects of education."