• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.121-133
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• 2013

Defect-free transfer service on the Next-generation wireless network extensive roaming mobile node (MN) to provide efficient mobility management has become very important. MIPv6(Mobility IPv6) is one of mobility management scheme proposed by IETF(Internet Engineering Task Force), and IPv6-based mobility management techniques have been developed in various forms. One of each management techniques, IPv6-based mobility management techniques for PMIPv6 (MIPv6) system to improve the performance of a variety of F-PMIPv6 (Fast Handover for Proxy MIPv6) is proposed. However, the F-PMIPv6 is cannot be excellent than PMIPv6 in all scenarios. Therefor, to select a proper mobility management scheme between PMIPv6 and F-PMIPv6 becomes an interesting issue, for its potenrials in enhancing the capacity and scalability of the system. In this paper, we develop an analytical model to analyze the applicability of PMIPv6 and F-PMIPv6. Based on this model, we design an Secure Smart Mobility Support(SSM) scheme that selects the better alternative between PMIPv6 and F-PMIPv6 for a user according to its changing mobility and service characteristics. When F-PMIPv6 is adopted, SSM chooses the best mobility anchor point and regional size to optimize the system performance. Numerical results illustrate the impact of some key parameters on the applicability of PMIPv6 and F-PMIPv6. Finally, SSM has proven even better result than PMIPv6 and F-PMIPv6.

• Spatial Information Research
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• v.23 no.2
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• pp.11-20
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• 2015

Abstract Monitoring is the most critical element in implementing "forest carbon offset project" to enhance the visibility of CSR (Corporate Social Responsibility) in North Korea. This study is intended to explore monitoring potential in terms of forest carbon offset project using satellite image for Baekdu mountain of North Korea. The permanent record of standard satellite remote sensing system demonstrated its capability of presenting area-wide visual evidences of monitoring conditions in Mt. Baekdu mountain of North Korea (site suitability, carbon stock by forest biomass growth, carbon emission by forest biomass loss, deforestation and degradation, environmental, social and economic impact specified in the Carbon Sequestration Law). It doesn't seem very difficult to comply with monitoring requirements for "the forest carbon offset project" due to the probative value of satellite data. Therefore, it could be considerable or realistic approach to utilize CSR based forest carbon offset project as a point of reform and open-door in North Korea. It is anticipated that this research output could be used as a valuable reference for Korea-based enterprises to ensure monitoring potentials using satellite image in exploring forest carbon offset project sites in North Korea.

• International Area Studies Review
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• v.22 no.1
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• pp.141-159
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• 2018

The study aims to explore the factors that affect the value perception, satisfaction, and frequency of smart phone taxi applications in Shanghai, China, and commuters. According to a survey conducted on the actual use of taxi application, the majority of the customers responded that they have been using taxi apps for more than one or two years, and the results showed that they use taxi apps once or twice a week. It also showed that the actual use of taxi apps varies depending on their age and academic background. Among the value attributes of smart phone taxi applications, the respondents perceived ease of use as the highest at 4.41 points out of 5 point scale, while the risk perception was the lowest at 3.34 points. Finally, when social demographic characteristics and the nature of taxi app use were controlled, the value perception variables had a significant influence on taxi application satisfaction. The higher the perception of service quality, usefulness, and system usability, the higher the satisfaction levels were. In particular, the impact of perceived usefulness and system usability perception was high.

• Journal of Cadastre & Land InformatiX
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• v.49 no.1
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• pp.123-144
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• 2019

The purpose of this study is to grasp factors the increasing population growth rate of the region through the regional and housing market characteristics. This paper has used multiple regression as the dependent variable (average of the population growth rate of 85cities during the last five years) and the independent variables analyzed the regional and housing market characteristics on the average. The results of the analysis, The regional and housing market variables that have had a significant impact on the regional population growth rate over the last five years are birth rate, employment rate, production available population growth rate, apartment rate, resale rights rate, and apartment turnover rate and the number of businesses per thousand and has decreased. In other words, The regions where the population increased by region for the last five years were the ones with the transfer of public institutions (innovation cities) and land development among the Seoul metropolitan area and non-Seoul metropolitan area excluding Seoul and metropolitan cities. The results of this study is intentional to suggest Policy point of view for the balanced regional development presented at the government level for other the metropolitan area, such as the small and medium cities that are undergoing population decline.

• Journal of Korea Water Resources Association
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• v.52 no.1
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• pp.71-82
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• 2019

The purpose of this study is to analyze the Mekong River streamflow alteration due to climate change. The future climate change scenarios were produced by bias corrections of the data from East Asia RCP 4.5 and 8.5 scenarios, given by HadGEM3-RA. Then, SWAT model was used for discharge simulation of the Kratie, the main point of the Mekong River (watershed area: $646,000km^2$, 88% of the annual average flow rate of the Mekong River). As a result of the climate change analysis, the annual precipitation of the Kratie upper-watershed increase in both scenarios compared to the baseline yearly average precipitation. The monthly precipitation increase is relatively large from June to November. In particular, precipitation fluctuated greatly in the RCP 8.5 rather than RCP 4.5. Monthly average maximum and minimum temperature are predicted to be increased in both scenarios. As well as precipitation, the temperature increase in RCP 8.5 scenarios was found to be more significant than RCP 4.5. In addition, as a result of the duration curve comparison, the streamflow variation will become larger in low and high flow rate and the drought will be further intensified in the future.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.3
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• pp.121-143
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• 2021

As the social economy emerges as one of the alternatives for solving social problems, interest and experiments on social franchise, a methodology for scaling the social economy, continue to increase. The success or failure of social franchise has a huge impact on franchisors, members of franchisees, as well as beneficiaries, local residents, and stakeholders in the region, but research on ways to increase their chances of success is still insufficient. Based on previous studies, this study tried to derive success factors by analyzing the effects of social franchise characteristics on business performance, and to understand the mediating effect of franchise autonomy, which is the differentiation point of social franchises, between characteristic factors and business performance. Social value orientation, social economy experience, local network utilization, and customer orientation were derived as characteristic factors affecting business performance, and franchise autonomy was set as a mediating variable, and a survey was conducted for franchisee members and their influence was analyzed. Through this study, it was found that social economy experience and local network utilization had a positive (+) effect on economic performance, and social value orientation, local network utilization, and customer orientation had a positive (+) effect on social performance. Also, the results of franchise autonomy playing a mediating role between social economy experience, local network utilization and economic performance, and a mediating role between local network utilization and social performance were presented. This study has significance as the first study to conduct a full-scale empirical study on social franchises. It is hoped that theoretical research on social franchises will be more active in the future and will be used as a useful reference for performance creation for organizations that seek or already operate social franchises.

• Journal of Korea Port Economic Association
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• v.39 no.4
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• pp.205-222
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• 2023

This study examines the impact of the changes to the port logistics before and after the COVID-19 pandemic. Specifically, the study focuses on analyzing the changes to Korea's container ports network. Furthermore, this study examines the influence of the ports in the container port network before and after the COVID-19 Pandemic using the network analysis method such as centrality indexes (degree centrality, closeness centrality, and betweenness centrality) to identify changes in the structure and properties of the networks between 2018 and 2021. In this study, We analyzes the changes in the container port networks of Busan, Gwangyang, Incheon, Ulsan, and Pyeongtaek-Dangjin, the five largest ports in Korea. As a result, in case of the Busan port, Singapore port plays an important role, while Busan port plays key roles in ports of Gwangyang, Incheon, and Ulsan. In case of the Gwangyang port, Port Kelang in Malaysia has become increasingly influential as a result of the Malaysian government's policies to overcome the pandemic. In the Incheon port, Japanese ports are playing intermediary roles between their ports and those in the Incheon port network. In the case of Ulsan port, the influence of Korean ports is high, and in the case of Pyeongtaek-Dangjin port, Southeast Asian ports play a role as intermediaries between ports. By analyzing the changes in Korea's port logistics networks, this study can be used as a reference point when responding to uncertainty situations that cause changes to port logistics, such as the COVID-19 pandemic, in the future.

• Journal of Korean Society of Transportation
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• v.22 no.5
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• pp.75-87
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• 2004

Along the seashore regions in Korea, though strong winds with very large strength are frequently witnessed, no system which can provide appropriate speed information for driving vehicle has been introduced. The driving against strong winds could be very dangerous because of the high possibility of accidents such as rollover and collision. These accidents usually resulted from driver's forced driving try even in difficult situation for steering vehicle, and sometimes overspeed without consideration of wind impact to the vehicles. To reduce accident caused by strong winds, it is important to inform drivers of appropriate driving speeds by perceiving strong winds. By setting up WIS at the main points where strong winds frequently appear and using the variable message sign(VMS) connected to the on-line whether information system, it tis possible to provide desired speed information, which can maintain vehicles' tractive force and maximum running resistance. The case study is conducted on the case of Mokpo-Big-Bridge, which is under construction at Mokpo city. The result show that in case the annual average direction of wind is South and the wind speed is over 8m/hr, the desired speed, which is required in order for vehicles running to South direction to maintain the marginal driving power, is 60km/hr. In addition, for the case of a typhoon such as Memi generated in 2003 year, if wind speed had been 18m/sec in Mokpo city at that time, the running resistance at the speed of 40km/hr is calculated as 1131N. This resistance can not be overcome at the 4th gear(1054N) level, therefore, the gear of vehicles should be reduced down to the 3rd level. In this case, the appropriate speed is 40km/h, and at this point the biggest difference between running resistance and tractive force is generated.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.39-48
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• 2016

According to the order receipt report over the past 10 years the overseas construction business total trades were 54.05% and 68.09% done by the Middle East and other industrial facilities respectively. In the Middle East based on data collected in 2014 the country with most overseas construction business is Saudi Arabia with 34.10%, and the industrial facility occupies the larger share with 56%. Overseas construction business is suffering from a reduction in work orders in the Middle East because of the recent oil price reduction. At this point of view, it is necessary to consider economy fluctuation for the diversification of construction type and work orders. This study analyzed, focusing in Saudi Arabia how the economical fluctuations of nations of progress can affect overseas construction business' trade orders. The analysis results demonstrated that most construction types depends on GDP, investment fund. Also industrial facility can be substituted with Architecture and civil engineering. This work is expected to be used as a basis for trade order amount maintenance and construction type diversification.

• Journal of Technology Innovation
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• v.24 no.4
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• pp.1-26
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• 2016

The period after the PhD has a huge impact on the careers of researcher from a researcher lifecycle perspective. This is a turning point which student receives guidance from professor and become an independent researcher. Furthermore, they learn to develop ideas for independent research, apply for grants and manage a project; they also form expert networks in related filed and publish papers to share their findings. This study focuses on the period between earning doctoral degree and being employed as a stable position in university. This study starts from a research questions that asks which factors of postdoctoral experience affect research output. In this study, the paper performance, especially co-authorship of paper, of postdoctoral researchers was investigated. The cumulative advantage theory and Matthew effect were employed to shed a light on this research question. The empirical work is based on the Survey & Analysis of National R&D program in Korea conducted by Korea Institute of S&T Evaluation and Planning (KISTEP). The correlations between the research output and characteristics of postdoctoral experience were verified. These results are expected to contribute as new empirical evidences on investigating knowledge transfer activities of new PhDs.