• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.2
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• pp.272-278
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• 2015

This paper analyzed interference impact between wireless headset and Wireless Fidelity which get a high possibility of simultaneously operating in the Industry Science Medical(ISM) bands. Analysis methods of Minimum Coupling Loss(MCL) and Monte Carlo(MC) were applied by using the characters and parameters referenced to Institute of Electrical and Electronic Engineers(IEEE) 802.11b. The protection distance between interferer (WiFi transmitter) and victim (Wireless headset receiver) was calculated through the MCL. The protection distance was obtained for the case of single interferer, and the maximum allowable number of multiple interferers was computed according to the cell radius of a victim system to meet 5 % below of interference probability by using a statistical analysis based on the MC method. The analysis results are expected to be used as a guideline to coexist the wireless headset and low power devices in the ISM band.

• Journal of Korean Society of Transportation
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• v.35 no.3
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• pp.183-196
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• 2017

In this study, policy evaluation scheme was established to encourage the efficient implementation of EcoMobility which has been expanding gradually all around the world. A total of eight evaluation goals and 22 evaluation items are reviewed and suggested based on the three major evaluation categories of "Basic elements for EcoMobility", "Land use and transport system for EcoMobility", and "Implications and impact of EcoMobility". The results of this study are as follows: the result of AHP analysis which reflects only the hierarchical structure shows a high priority in "Elements for EcoMobility promotion", "Eco-fiendly transport infrastructure", and "Safety in transport". While in result of ANP which considered the elements' dependencies, "Eco-fiendly transport Services", "Welfare in transport", and "Environment by transport" have high weights and importances. In conclusion, this study would be useful to make reasonable judgment based on the analysis results of the two techniques in order to ensure reliability in evaluation of EcoMobility policy. Furthermore we have confirmed appropriate evaluation technique between AHP and ANP which is better to reflect the features of EcoMobility.

• Journal of Wetlands Research
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• v.20 no.1
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• pp.63-71
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• 2018

The particle filtration mechanisms in an infiltration trench should be varying due to the different hydraulic conditions during stormwater runoff. The understanding of these variations associated with different filtration mechanisms and their effect on the particle removal efficiency is of vital importance. Therefore, a LID (Low Impact Development) system comprising of an infiltration trench packed with gravel and woodchip was investigated during the monitoring of several independent rainfall events. A typical rainfall event was divided into separate regimes and their corresponding flow conditions as well as filtration mechanisms in the trench were analyzed. According to hydraulic conditions, it was found out that filtration changes between vertical and horizontal flows as well as between unsaturated, saturated, and partially-saturated flows. Particle separation efficiency was high (55-76%) and was mainly governed by physical straining during the unsaturated period. It was then enhanced by diffusion during the saturated period (75-95%). When the trench became partially saturated at the end of the rainfall event, the efficiency decreased which was believed to be due to the existence of a negatively charged air-water interface which limited the removal to positively charged particles.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.1
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• pp.1-17
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• 2018

Objectives: This research is part of a study to be conducted over five years starting from 2017 by the Ministry of Environment on the development of technologies to evaluate the impact of chemical accidents on the human body. Methods: For this research, a five-stage specific study method was developed. Results: In brief, the developed health risk assessment method can be summarized as follows. First, a health risk assessment system was built based on the guidelines set forth by the USA NRC/NAS. Second, based on the disease manifestation theory, the health risk assessment method was divided into 1) a carcinogenic health risk assessment method focused on all carcinogens except non-genotoxic carcinogens and 2) a non-carcinogenic health risk assessment method focused on noncarcinogens including non-genotoxic carcinogens. Third, the detailed contents of the health risk assessment method were developed in four stages(hazard identification, dose-response assessment, exposure assessment, and risk determination) through theoretical consideration of the assessment of the level of health risk related to chemical exposure. Finally, a health risk assessment methodology, classified into stages to address acute, subacute/subchronic, and chronic conditions was developed after considering the physicochemical behavior of hazardous chemicals upon implementation of countermeasures after a chemical accident. Conclusions: A method to evaluate the health risks related to toxic chemicals generated by chemical accidents was developed. This study was performed with the purpose of developing a mathematical health risk assessment method to evaluate the health effects of exposure to hazardous chemicals upon implementation of emergency countermeasures after chemical accidents.

• Asia pacific journal of information systems
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• v.17 no.3
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• pp.1-24
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• 2007

With the development of information technology (IT), various information systems (IS) such as Web-based systems and mobile systems have appeared utilizing different technologies. However, recent studies on IS use and user satisfaction rarely account for technological differences among IS and environmental characteristics where IS are intended to be used. The purpose of this research is to investigate the determinants of the use of Web-based ticketing systems for cultural activities and to empirically validate their relationships. Environmental psychology suggests that human beings respond to external stimuli from environments with their emotions, and their emotional states influence human actions, e.g., IS use in this research. Applying environmental psychology to the use of Web-based systems in the culture and entertainment industry, we propose that web site characteristics first influence a user's internal state of mind (i.e., flow) and then the flow state influences the IS use. Studies related to the state of flow collectively affirm the key role played by the flow construct in shaping individual attitudes and behaviors toward IS. Users' flow states are captured by their shopping enjoyment, perceived behavioral control, and the level of concentration on the IS use. Referring to social presence theory, we have included such web site characteristics as content quality, context of web site, and community quality. In our research model, a second order construct is utilized to represent web site quality, because flow theory suggests that holistic experiences with web-based systems (rather than individual characteristics of the web site) are important in explaining the IS use. Further, we have included trust as another important factor influencing the IS use since business transactions on the web encompass higher uncertainty comparing to offline transactions. In order to test our hypotheses, we have conducted an online survey which results in 1,141 valid responses in the final sample. The data were collected from respondents who have experiences in Internet ticketing systems. Although it was a convenient sample, the sample represents a wide variety of user demographics. Validity and reliability of the research instrument were tested and research hypotheses were examined using PLS Graph 3.0. The results indicate that web site characteristics significantly influence the level of user concentration, user's enjoyment in shopping, and perceived behavioral control. Further, the use of Internet ticketing systems is influenced by users' flow states and trust in the web channel. User satisfaction is turned out to be affected by the use of Internet ticketing systems. Unlike extant research on the relationship between web site characteristics and its use, our study has found that, in the culture and entertainment industry, the impact of web site characteristics on IS use is mediated by a user's flow state. This finding has a practical implication that web site design should include as many features that enhance shopping enjoyment and concentration. Other practical implications of these findings and future research implications are also discussed.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.320-333
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• 2016

This study was carried out to elucidate the development of unprecedented water-bloom caused by a single species of colonial green algae Eudorina elegans in the upstream area of the Seungchon weir located in the Yeongsan River from late April to May 2013. The Yeongsan River is typically regulated system and the waterbody is seriously enriched by both external and internal sources of nutrients. Seasonal algal outbreaks were highly probable due to various potential factors, such as the excessive nutrients contained in treated wastewater, slow current, high irradiation and temperature, in diatom (winter), green algae (spring) and bluegreen algae (summer). Spring green-tide was attributed to E. elegans with level up to $1,000mg\;m^{-3}$(>$50{\times}10^4cells\;mL^{-1}$). The bloom was exploded in the initial period of the algal development and after then gradually diminished with transporting to the downstream by the intermittent rainfall, resulting in rapid expansion of the distribution range. Although the pulsed-flows by the weir manipulation was applied to control algal bloom, they were not the countermeasures to solve the underlying problem, but rather there still was a remaining problem related to the impact of pulsed-flows on the downstream. The green-tide of E. elegans in this particular region of the Yeongsan River revealed the blooming characteristics of a colonial motile microalga, and fate of vanishing away by the succeeding episodic events of mesoscale rainfall. We believe that the results of the present study contribute to limno-ecological understanding of the green-tide caused by blue-green algae in the four major rivers, Korea.

• Journal of fish pathology
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• v.12 no.1
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• pp.32-41
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• 1999

Ozonization for rearing seawater in land-based culture system has recently been utilized for disinfection of pathogenic microorganisms and improvement of water quality. This study was conducted to examine the effects of total residual oxidants (TRO) in ozone-treated seawater on survival, blood parameters, osmolality and oxygen consumption, and gill tissue of the flounder. Paralichthys olivaceus. Experiments were carried out with the starved flounder of 12~19 cm in total length at $20^{\circ}C$. The 48-hr and 96-hr $LC_{50}$ for the flounder amounts to 26.4 ppb and 22.3 ppb, respectively. With increase of TRO concentration from 24 to 39 ppb, the values of hematocrit, hemoglobin concentration, red blood cell count and osmolality of the flounder with respect to exposure time were significantly elevated, however, the oxygen consumption rates decreased. In the case of the fish exposed to 13 ppb for 96 hrs, blood glucose increased with an elapse of exposure time, while survival rate was 100%. Death apparently resulted by massive destruction of gill lamellar epithelium, severe osmotic imbalance and the lack of oxygen uptake. The results of this experiment indicated that to protect aquaculture organisms, the ozone-treated seawater should not contain any residual oxidants, and that relatively long-term exposure to TRO of low concentration can impact on survival and physiological conditions of the flounder.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.359-368
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• 2016

In the 21st century, the Korean university education system is focused on innovation and change, including cooperation between industry and universities. It should be a goal to foster an industry-university ecosystem through interactions between universities and industry. Therefore, it is important to measure their relationships and to find advisable ways to measure the final results of industry-university cooperation. This paper sets out the achievements in cooperation and the satisfaction from such enterprises and measures mutual relationships influencing satisfaction from industry-university cooperation as to adherence and cooperation. Therefore, this research focuses on regression equation analysis in order to analyze the influence from satisfaction with industry-university cooperation based on factors in the relations between industry and universities. Also, as we examined the multicollinearity problem, before analyzing multiple regression, the multicollinearity problem appeared to be relatively irrelevant. In particular, the satisfaction variable, which can also be set as a subordinate variable, was in this research constructed as a high-dimensional subordinate variable composed of five individual variables. We then analyzed how the adherence construct factor and degree of cooperation construct factor influences the respective and subordinate satisfaction variables. As a result, the degree of realization of local customized programs was shown by the most significant variables. The biggest factor influencing satisfaction with industry-university cooperation proves the degree of realization for appropriate programs under local conditions, such as education, research, and technique guidance.

• Journal of Distribution Science
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• v.14 no.4
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• pp.117-125
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• 2016

Purpose - As consumers' needs for purchasing fresh and safe food have been bigger in Korea, their interest in local food is also growing recently. So, the number of local food stores has been increased from 3 in 2012 to 103 in 2015. Local food stores should operate a business responding consumers' needs in order that local food stores are not to be a one-time fad. Therefore, the purpose of this study is to analyze the characteristics of consumers who use a local food store and provide helpful implications to design a strategy for sustainable growth of local food store. Research design, data, and methodology - In this study, Probit model was used for empirical analysis in order to examine the effect of purchase choice attributes of agricultural products, consumer's satisfaction, and their demographic factors upon the intention to use a local food store. After estimating coefficients of the probit model, marginal effects were calculated as a standard normal, and cumulative distribution is differentiated with respect to explanatory variables. To collect the data, questionnaire survey was carried out with the consumers using the local food store (Youngjin Nonghyup near to Jeonju city located in Jeollabuk-do). Result - The data analysis found that the more consumers are satisfied with local food store, the higher intention they have to use the local food store. In addition, it was known that the factors related to quality of agricultural products and shopping convenience among the purchase choice attributes have a considerable impact on the purchase intention of a local food store. In demographic factors, income was turned out to be an important factor affecting purchase intention of local food. Such a result supports the hypothesis that high income consumers are likely to purchase local food, which is based on the inference that consumers who have a high income tend to pursue wellbeing life. Futhermore, information delivery, through a reputable media source among general factors, was known to play an important role in forming an intention to purchase local food. According to the analysis of marginal effects, probability of purchase intention of a local food store is increased by 11.4%, if a monthly average income of a household is above 4.5 million Won(Korean currency). If purchasing satisfaction with local food stores is high, the probability of purchase intention would be increased by 24.1%. Likewise, such a probability goes up by 8.7%, 5.8%, respectively as an increasing one unit of quality of agricultural products and shopping convenience of local food stores, respectively. Conclusion - For attaining sustainable growth in a local food store, it is considered necessarily to establish a proper store operation system to meet consumers' needs, especially for quality and shopping convenience of local food. Moreover, as it was found that appropriate communication through media source has a positive effect on the intention to use local food store, PR activity seems to be necessary to expand the consumers' demands for local foods.

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.13-31
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• 2016

Despite expectations of short- or long-term positive effects of corporate social responsibility (CSR) on firm performance, the results of existing research into this relationship are inconsistent partly due to lack of clarity about subordinate CSR concepts. In this study, keywords related to CSR concepts are extracted from atypical sources, such as newspapers, using text mining techniques to examine the relationship between CSR and firm performance. The analysis is based on data from the New York Times, a major news publication, and Google Scholar. We used text analytics to process unstructured data collected from open online documents to explore the effects of CSR on short- and long-term firm performance. The results suggest that the CSR index computed using the proposed text - online media - analytics predicts long-term performance very well compared to short-term performance in the absence of any internal firm reports or CSR institute reports. Our study demonstrates the text analytics are useful for evaluating CSR performance with respect to convenience and cost effectiveness.