• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.56-75
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• 2018

Korean Photochemical Assessment Monitoring Stations (PAMS) have been established since the late 2001 to monitor ambient air concentrations of VOC species, which would enhance understanding photo-chemical formation of ozone and subsequently contribute to developing efficient ozone control strategies. The present study aims at identifying major VOC species and examining their trends by analyzing PAMS monitoring data collected from the year 2006 to 2016. All the 18 PAMS sites operated by the Ministry of Environment were included in the study. PAMS monitored the 56 target VOC species, which are classified into four groups, alkenes, lower alkanes ($C{\leq}3$), higher alkanes ($C{\geq}4$), aromatics. The higher alkanes and aromatics dominated over the lower alkanes and alkenes in the type 2 and 3 PAMS sites except Joongheung site. N-butane was a major alkane species, toluene was a major aromatic species and most of VOCs showed decreasing trends in these sites. On the other hand, only the alkenes showed decreasing trends at the Joongheung site in Yeosu. Major sources of abundant species such as ethane, propane, n-butane, toluene were estimated by analyzing seasonal variations, correlation with other VOC species, and emission profiles. A major source of n-butane was identified as LPG cars, while major sources of toluene varied considerably from one site to another. The lower alkanes were composed of ethane and propane, both of which showed a strong seasonal variation, low in the summer and high in the winter, indicating that a major source might be the heating by gaseous fuels. Ozone formation potentials of VOC species were evaluated by applying MIR and POCP to the measured VOC species concentrations. Toluene contributed the most to total ozone forming potentials followed by m,p-xylene for all the type 2 and 3 PAMS sites except for two sites in Yeosu-Gwangyang. Ethylene and propylene were the first and second contributors to total ozone forming potentials at Joongheung site in Yeosu.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.1-15
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• 2018

Nation-wide systematic and comprehensive measurements of air quality criteria species have been made over 340 sites currently in Korea since 1990. Using these data, temporal and spatial trends of $SO_2$, $PM_{10}$, $NO_2$, $O_3$, CO and $O_x(NO_2+O_3)$ were analyzed to characterize and evaluate implementing efficiency of air quality policy and regulations. Due to strict and effective policy to use cleaner fuels in late 1980s and 1990s, the primary pollutants, such as $SO_2$, CO, and $PM_{10}$ decreased sharply by early 2000s in all parts of Korea. After this period, their concentrations declined with much lower rates in most parts of Korea. In addition, isolated but noticeable numbers of places, especially in major ports, newly developing towns and industrial parks, sustained high levels or even showed further degradation. Despite series of emission control strategies were enforced since early 1990s, $NO_2$ concentrations haven't changed much till 2005, due to significant increase in number of automobiles. Nevertheless, we confirmed that the staggering levels of $NO_2$ and $PM_{10}$ improved evidently after 2005, especially in Seoul Metropolitan Area (SMA), where enhanced regulations for $NO_2$ and $PM_{10}$ emissions was imposed to automobiles and large emission sources. However, their decreasing trends were much lessened in recent years again as current air quality improvement strategies has been challenged to revise further. In contrast to these primary species, annual $O_3$, which is secondary product from $NO_2$ and volatile organic compounds (VOCs), has increased consistently with about 0.6 ppbv per year in every urban part of Korea, while yearly average of daily maximum 8-hour $O_3$ in summer season had a much higher rate of 1.2 ppbv per year. Increase of $O_3$ can be explained mainly by reductions of NO emission. Rising background $O_3$ in the Northeast Asia and increasing oxidizing capacity by changing photochemistry were likely causes of observed $O_3$ increase. The future air quality policy should consider more effective ways to lower alarming level of $O_3$ and $PM_{10}$.

• Journal of the Korean Regional Science Association
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• v.33 no.4
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• pp.3-17
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• 2017

This study ranks by developing an urban competitiveness index of major global cities, including seven cities in Korea using data from the Global Cities Forecast (2013) provided by Oxford Economics. The City competitiveness index is selected from 18 indicators including scale index, ratio index, growth rate index while Gini coefficient is used for distribution index. In order to analyze the relationship between the competitiveness index and the distribution index, we use the LOGIT panel regression model. As a result, the increase in income inequality (Gini coefficient) has a negative effect on the economic growth rate in 5-year time lag shown statistically significant. We have compiled global rankings of 770 city competitiveness based upon 19 indicators by combining the global competitiveness index and the distribution index. The trend of rank shows that 7 Metropolitan Korean Cities are expected to decline substantially over the period. In particular, Seoul ranked $59^{th}$ in 2010 and $74^{th}$ in 2015. Its ranking is expected to be decline to $185^{th}$ in 2030. The declining competitiveness of Korean cities is expected to lead to a weakening of Korea's national competitiveness in the long run. Accordingly, it is imperative to identify problems and seek strategic plans to secure global urban competitiveness.

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.151-162
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• 2012

It is not surprising to hear news about irresistible natural disasters all over the world due to climate change. Korean Government has focused on developing a variety of green technologies to reduce green house gasses, in particular, carbon dioxide. This study suggested 18 technology divisions for achieving green highway technology development in six different sub-sectors considering life-cycle of roadway and surveyed 29 highway and/or transportation professionals of three institutes using AHP(Analytical Hierarchy Process) analysis to construct "Green Highway"and realize carbon emission reductions and energy use efficiency in a road sector in Korea. Expert Choice Software was used to rank 18 technology divisions weighted by two-level choices. Transport Operating Infrastructure Improvement, Roadway Policy Implementation, Green Transportation(such as Pedestrian and Bicycle) were highly ranked by respondents according to results of the AHP modeling. Among the 18 divisions, technology policy for supporting R&D investments from development to commercialization was ranked as the most significant one to be focused. Green Transportation Facility Design/Construction/Operation and Eco-Friendly Roadway Plan were followed as expected since professionals have thought that the planning/design step of the life-cycle is a starting point to reduce carbon dioxide from roads more and more. Additionally, comparing the results with the Government investment trend 2006-2011 for the roads, it can be interpreted that the Government should invest to the R&D area more widely than before to promote element and core technology development for Green Highway Construction. Above all, small and mid-sized businesses have to be invested as well as encouraged to undertake green highwayrelated objects to accomplish the divisions which ranked high.

• Journal of Sensor Science and Technology
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• v.7 no.1
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• pp.31-38
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• 1998

Multi-channel sensors can be used to increase the reliability and remove the random iloise in ion-sensitive field effect transistors(ISFETs). Multi-channel sensors is also an essential step toward potential fabrication of sensors for several ionic species in one device. However, when the multi-channel sensors are separately biased, the biasing problems become difficult, that is to say, the bias circuit is needed as many sensors. In this work, a circuit for biasing the four pH-ISFETs in null-balance method, where bias voltages are switched, was proposed. The proposed concept is need only one bias circuit for the four sensors. Therefore it has advantages of smaller size and lower power consumption than the case that all sensors are separately biased at a time. The proposed circuit was tested with discrete devices and its performance was investigated. In the recent trend, sensor systems are implemented as portable systems. So the verified measurement circuit was integrated by using the CMOS circuit. Fortunately, ISFET fabrication process can be compatible with CMOS process. Full circuit has a mask area of $660{\mu}m{\times}500{\mu}m$. In the future, this step will be used for developing the smart sensor system with ISFET.

• Korean Security Journal
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• no.18
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• pp.143-167
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• 2009

As of entering the 21st century, a trend in the field of a private security industry among the advanced countries have been increased a qualification system and train session to meet the needs of professionalism. Intensifying the professionalism in Korea, education and train system has been initiated to change but the oligopoly market already formulated due to impractical selection standard and management of education system. Issuing certification and offering basic training through a designated institution for the purpose of improving quality of the private security industry worker, its practical effectiveness were lower than expectation. Rather certification-holder or security agency, institution or truster's rent-seeking behavior have been increased by occupational licensing system. The founded results, which were associated to problems in selecting and educating to the private security guard, in this study were that any verification has been initiated towards dual-system in official approval and structural problems in education system, and non-existence of verification for professionalism and management capability to security agency owner and its upper managerial level. Current a dual system in an officially authorized verification system and completion of security guard credential requested change to an unified official qualification verification system to solve those problems. Ranges of an applicant to the unified official qualification verification system should be extend to the whole population in the private security industry. Moreover, minimization of the dead-weigh loss, which is caused by oligopoly phenomenon while using its market-dominant status, increasement number of designated institution, which allows self-regulating competition, and endowment of autonomy, which is in selecting education and agency, were requested to solve the problems in selecting and educating to the private security guard. In order to minimize stated problems while maintaining objectiveness, a new manage and supervise institution, which is called a 'private security industry committee', should be establish. The private security industry committee is a formation of governance network which are participated from professional group to civil organization.

• Journal of Technology Innovation
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• v.20 no.2
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• pp.29-48
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• 2012

As the complexity and uncertainty of social and economic systems increase, the strategic foresight that actively and effectively responds to the environmental changes becomes important. A wide range of future forecasting methods are available for strategic foresight. Selecting one of the methods depends on several factors such as availability of time and financial resources and the objectives of the exercise. Although trend extrapolation analysis has been used for many years, scenario planning is being widely used by government and corporate as a tool for strategic decision making in recent years. Generally, scenario planning is carried out through workshop, in which experts with diverse backgrounds exchange information, views, and insights and integrate the diverse viewpoints. However, only a small number of experts can participate in a workshop and citizen opinion is not easily transformed into the policy for the scenario exercise due to the limitation of budget and short duration of a project. It is also much harder to develop creative ideas in the workshop because of the limited time and space. In this study, a new scenario process combining scenario workshop and wiki is proposed to overcome the limitation of scenario workshop. This combined approach can be more productive than using scenario workshop alone when developing new ideas. In this study, we applied the combined approach to develop scenarios for the strategic foresight of future media and present suggestions for improving the process.

• Korean Journal of Construction Engineering and Management
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• v.14 no.4
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• pp.84-96
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• 2013

Recently, architectural design has been changing from formal design to freeform design due to the digitalization of construction industry. Especially, the formal design has been accepted as a design trend recently and applied many times as a design concept in the architectural design competitions such as turn-key. However, various deflects such as water leak and cracks have been occurred because the traditional construction methods had been applied without any revision or adaptation of the formal construction method for the freeform building construction. Design and construction of freeform building has been developed as an new method in order to solve the problems and minimize the construction duration and cost for the freeform building. Therefore this research deduced the positive implications for developing freefrom envelope by analyzing the domestic and abroad cases and proposed the considerations during design and construction of the freeform envelope as follows. First, the freeform design should consider the constructability for the freeform envelope. Second, manufacturing technology for the two-way curvature of the unit panel should be developed. Third, exposed concrete form method should be developed for the freeform envelope of concrete. Forth, material characteristics, construction method and facility management should be considered in order to manage precipitation and keep water-proof according to the classification of the freeform envelope area.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.95-105
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• 2016

The purpose of this study is to identify the possibility of developing new jelly product with healthy function by the physio-chemical analysis and sensory test of jelly sample groups adding each 20~80% of squeezed Indian spinach liquid. Sugar contents of squeezed Indian spinach liquid was $3.4^{\circ}Brix$. From chromatography, L-value has been decreased by increasing the adding rate of squeezed Indian spinach liquid, and both a-value (redness) and b-value (yellowness) have shown similar trend. According to the measuring result of squeezed Indian spinach liquid the DPPH radical scavenging activity was 15.67 mg/mL, and its total polyphenol contents was 7.00 mg/g. By increasing squeezed Indian spinach liquid, the DPPH radical scavenging activity and total polyphenol contents have shown increasing tendency. Among textures of squeezed Indian spinach liquid, for hardness, sample group of 20% adding was the highest by 4.27%, and for adhesiveness the sample group of 20% adding was the highest by 2.48%, and the lowest was sample group of 80% adding with 0.91%. From the result of sensory test the sample group adding 40% of squeezed Indian spinach liquid has been appraised the most highly in color, scent, sweet taste, chewiness, moistness, and general preference. According to the above results, it is understood that the 40% adding rate of squeezed Indian spinach liquid, when producing jelly, would be the most compatible rate of adding.

• Informatization Policy
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• v.19 no.2
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• pp.57-84
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• 2012

If we observe the formation of communities of people and participation methods within them, we can see that those communities are developing more efficiently due to the penetration of smart phones and the growth of SNS. This trend also has an impact on information sharing activity between people and enables more active information sharing than ever before. But information sharing on SNS does not just involve the SNS users sharing information with each other. Important factors affecting the information sharing activities include the type of relationship between the users and the attitude of the information sharing individuals. Accordingly, this study selected perceived social support, perceived social influence, and perceived network structure as the factors that affect the continuous intention of people to use SNS, and performed a higher order factor analysis on those factors. Between continuous intention to use SNS and intention to share information, we selected relationship quality and information sharing behavior and executed a path analysis between the factors. We carried out an empirical analysis by utilizing SPSS 18.0 and SmartPLS 2.0 as analysis tools. Using these tools, we investigated the factors influencing continuous intention to use SNS, and tested the significance between the role and path of relationship quality and information sharing behavior between continuous intention to use SNS and intention to share information.