• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.29-39
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• 2018

Long-term variation of zooplankton community and species composition was studied from 2003 to 2014 in a deep reservoir, Lake Soyang, in monsoon climate region, Korea. In addition, we examined the correlation with environmental factors. Annual precipitation of watershed showed a large variation in the $705{\sim}1,779mm\;yr^{-1}$ and more than 70% of it was being concentrated from June to September. The water quality of Lake Soyang was shown a clearly seasonal variations and particularly turbid water flowing into the lake during rainy season was the most important environmental factors. Zooplankton community in Lake Soyang showed a significant difference before and after 2006. Zooplankton biomass has shown a large increase and also showed a change in the zooplankton community structure since 2006. The of zooplankton showed positive correlation with temperature and BOD, Chl. a, TP concentration. These results are considered that nutrient and organic matter contained in the turbid water influences the increase in zooplankton biomass and species composition. However, water quality was limited to account for the increase in biomass of zooplankton. For example, increase of small zooplankton density (rotifer; Keratella cochlearis, Polyarthra vulgaris) in spring which is dominated by diatoms (large size; Melosira, Synedra etc.) is considered as a bottom-up effect by the microbial loop. And increased density of crustaceans in autumn was considered a top-down effects by the relationship between predator and prey of microzooplankton and mesozooplankton. In other words the inflow of allochthonous organic matter during rainy season also affected to zooplankton food web in Lake Soyang. In conclusion, biomass, diversity and long-term variations of zooplankton in Lake Soyang were determined by physico-chemical factors but also it is considered that biological interactions is important.

• Journal of Korea Trade
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• v.26 no.7
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• pp.145-166
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• 2022

Purpose - The field of online videos has seen rapid changes in information and communications technology (ICT) development. Despite active academic research on the use of online platforms, few studies have analyzed the relative importance among the factors determined. In this study, the relative importance of factors found in previous studies was identified for users of online video platforms in China and Korea. Through this, factors that should be considered first in research on online video use were derived. In addition, the quality level of online video platforms currently used in China and Korea was measured and used for analysis. The analysis results can provide information for companies to enter Chinese and Korean markets and also be useful to platform providers aiming to increase usage. Design/methodology - Among the factors of Online Video Usage identified in previous studies, 13 factors to be studied were selected through focus group interviews and hierarchized into 2 layers. For the analytic hierarchy process (AHP), each factor was designed as a pairwise comparison questionnaire. The survey included questions on the quality of online video platform currently in use. Data collection was conducted on 16 platforms in China and 11 platforms in Korea, and the relative importance of factors and user perspectives was compared and analyzed using importance performance analysis (IPA). In the analytical process, platforms were divided into over-the-top (OTT) group and Creator group according to the weight of user-generated content, and data analysis focused on these groups. Findings - As a result of AHP, China and Korea showed both "Fun" and "Interests" factors at the top, while the importance of the Entertainment factor "Vicarious satisfaction" was very different for China and Korea. "Relationship with content creators" was the most important factor in China, but it ranked the lowest in Korea. The IPA showed that the factors with high importance and performance were fun, interests, and easy accessibility for both China and Korea. In contrast, the factors that showed low performance compared to high importance in China were relationship with content creators, relationship with acquaintances/friends, and trustworthiness. As for Korea, vicarious satisfaction was observed; thus, this study has raised the need for academic and industrial interest in vicarious satisfaction. The results show that fun, interests, vicarious satisfaction, and easy accessibility of the platform are factors that must be included in further studies on online videos. Originality/value - Existing studies related to the use of online platforms have derived factors or focused on the influence relationship between factors and performance. However, few studies have analyzed the relative importance among the determined factors. This paper explores factors to be considered in future studies by deriving the relative importance between these factors from the perspective of users in China and Korea.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.10
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• pp.1571-1583
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• 2008

The study aimed to investigate the actual condition of working clothes in the Changwon National Industrial Complex and to analyze the industrial workers' satisfaction with and preference to the working clothes in terms of the clothing performance and work motion factors. 1 major companies in machinery, automotive, industrial engineering, shipbuilding and rolling stock industries located in the industrial complex were selected as the subject firms. Approximately 900 workers responded to the questionnaire designed for the research and the results derived from the research were as follows. (1) The subject employees were divided into 4 work groups, i.e. the $1^{st}$ work group: managerial, general affairs, sales, production planning; the $2^{nd}$ group: quality assurance, material planning and distribution, product inspection; the $3^{rd}$ group: electric, facilities, machinery, vehicles; and the $4^{th}$ group: cutting, pressing, rolling, welding and coating. (2) The significant work environmental factors considered by all work groups were air ventilation, noise and dust factors and in particular, the most dissatisfied factors evaluated by manufacture workers were insulation, noise, dust and vibration. (3) According to the employees' work motion evaluation, the work motion diversity and frequency increased in proportion to the degree of work intensity. Besides, manufacture workers more frequently wore the working clothes even during the off-duty hours comparing to the evaluation of the other work groups. (4) The most important clothing performance factors considered by manufacture work groups were perspiration absorption, stretch, air permeability, tactile sense softness, soil proof in order.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.5
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• pp.103-114
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• 2012

The purpose of this research is classifying stream into different types depending on various factor from the perspective of stream corridor restoration and using it as basic data, which are used to consider efficient management and planning for the healthy stream according to the characteristic by types. In this study, 130 points of location of the Nakdong river basin which consist of various geographic factors have been chosen and hierarchical cluster analysis has been carried out in these points by using biological and physiochemical factors whose health can be considered to be predicted and evaluated. As a result of cluster analysis, there were three divided types. Type A whose biology and water quality are considered the best was the highest in forest area percentage so that it was classified into natural stream. Type B was classified into a rural region stream with a mixture of urban and agricultural region. Type C, with the most damaged water quality and biology health had the most urban region surface area and was named as urban region stream. Moreover, an overall restoration strategy according to characteristic by stream types was set. By the results of correlation analysis on factors, water quality showed a high correlation with biological properties and was affected by surrounding land usage. In evaluation of streams, it proves the need to consider not only other habitat's geographical and biological factors but also the water quality and land usage factors. There needs to be further research on stream ecosystem functionality factors and structural aspects by using a more objective and total evaluation result in selecting additional index and various other specific classification methods by stream types and its restoration strategies.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.875-881
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• 2011

This study examined factors influencing college science learning from the perspectives of college students and high school science teachers. Using a survey created based on focus group interviews, college science majors and high school science teachers rated various factors of high school learning that positively influenced college science learning. Findings suggested that the perceptions differed by college major: the physics major students considered math proficiency and logical thinking skills as the important factors; chemistry major students and biology major students considered English proficiency and basic scientific knowledge as the most important factors. Both college students and science teachers emphasized basic science knowledge and math proficiency. However, differences between the two groups were also found in that the students perceived more need to learn about experimentation than the teachers whereas the teachers had a priority in increasing advanced science content.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.440-447
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• 2011

Selecting a suitable place is to determine the attributive conditions and qualified areas for the aim as factors and is to be fulfilled systematically for selecting the area which satisfies all these. This research tries to achieve a rational suitability analysis of residential development using the GIS modeling method and the hierarchical analysis process. A spatial and attributive analysis has been systematized for selecting a suitable place for the study and GIS analysis model has been used for the effective conclusion drawing for different levels. As a next step, a quantitative and qualitative evaluation index was created through complex consideration of the criteria and decision factors of the location selection, and weights were added depending on the relative importance of these factors. In particular, 3D terrain model simulation method has been used in order to reflect the aesthetic factors of the scenery which is an element of the subjective evaluation factors and considered qualitative and subjective evaluation factors which were not considered for the existing AHP technique. After the research, a location that satisfies complex requirements was found rapidly and accurately through the GIS model and hierarchical analysis.

• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.89-96
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• 2012

In this study landslide causal factors which are considered to have the same effect in assessment techniques are categorized and their impact on landslides is analyzed to acquire reasonable weighting factors in the landslide hazard. Results are compared to those of the Assessment Chart developed by National Institute for Disaster Prevention (NIDP) and the adequacy and proper portion for landslide causal factors are considered. The Artificial Neural Network (ANN) method applied to 28 landslide areas is incorporated to evaluate the reasonable rating. Results show that the following items in the Chart are necessary to modify their portions in order to implement the precise assessment results: 1) Estimated damage; 2) Tension crack; 3) Existence of valley.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.313-323
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• 2006

Forest Canopy Density is a dynamic process mediated by various natural and anthropogenic factors. It can be changed over time and locations in the same forest type and landscape. However, human dimensions are considered as the primary force of landscape change and subsequent forest canopy loss in tropical regions of the world. Many studies have been indicated that roads have a far greater impact on forests than simply allowing access for human use. Similarly, rivers have been used as means of transportation, hence illegal logging and felling further deplete forest canopy density. The main objective of this study was to investigate the spatio-temporal dynamic alterations of Forest Canopy Density (FCD) across with site associated factors such as biophysical, physical and human interferences in tropical region of Nepal from 1988 to 2001. Landsat TM and ETM+ of 1988 and 2001 were used to assess the spatial and temporal dynamic alterations of FCD. This analysis revealed that distance to human settlements at P=<0.01, rivers, human interferences (path and fire) and species composition had a statistically significance at P=<0.05 level. However, other factors did not show any significant relation. So, we concluded that understanding of dynamic alterations of FCD with respect to factors was quite complex phenomena. Other surrounding environment could also playa significant role. A comprehensive analysis could be required to understand such complexities. Therefore, additional factors such as climatic, biophysical, social, and institutional with respect to spatio-temporal variability should be considered for the better understanding of canopy dynamic.

• Journal of The Korea Institute of Healthcare Architecture
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• v.30 no.3
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• pp.45-56
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• 2024

Purpose: It is important to note that the relative importance of risk factors should be identified to successfully complete the remodeling project of general hospital. Approached by analytic hierarchy process (AHP), the present study aimed to systematically evaluate the risk factors for remodeling of general hospital. Methods: The present work classified the risk factors of general hospital remodeling into four major categories including the requirements survey stage, planning and design stage, dismantling and construction stage, and maintenance stage. In addition, four sub-categories were derived from each major category factor. Furthermore, five major categories and four subcategories were selected to be considered from the perspectives of two stakeholders of contractor and constructor. The relative importance of the major and sub-categories factors was calculated using the AHP technique on the survey data collected from 49 respondents who participated in the survey study. Results: The results indicate that, the risk factor of requirements survey stage was found to be the most important risk factor to consider among the four major categories of factors. Also, insufficient preliminary investigation, design inconsistencies in architecture/mechanics/electricity, occurrence of safety accidents, and insufficient review of various equipment capacities and performances were found to have the highest priorities of each subcategory factor group included in the four major categories. From the perspective of contractor, the error in predicting the construction period was found to be the most important risk factor. The occurrence of safety accidents during construction was found to be the most important risk factor to be considered by constructor. Implications: The result of the current work should provide important insights and guidelines for the risk management activity that contributes to controlling the project time, cost, and scope required for general hospital remodeling.

• Korean Journal of Child Studies
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• v.30 no.1
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• pp.11-25
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• 2009

This study aimed to investigate protective factors and risk factors in elementary students' life satisfaction. Participants were 2844 (1524 boys, 1320 girls) children who grades were 4th, 5th, 6th in KYPS (Korea Youth Panel Survey). Data mining decision tree model was performed with sex, appearance, delinquency, family income, attachment to parents, parental monitoring, attachment to teachers, academic achievement, peer delinquency, and attachments to peer. The results revealed that : (1) For 4th graders, academic achievement, attachment to parents, and appearance were significant predictors for life satisfaction. (2) For 5th graders, attachment to parents, academic achievement, parental monitoring and appearance were significant predictors for life satisfaction. (3) For 6th graders, attachment to parents, appearance, parental monitoring and delinquency were significant predictors for life satisfaction. Protective factors and risk factors were changed according to interactions between significant independent variables. These results suggest that children's diverse conditions should be considered individually in programs for children's life satisfaction.