• Current Research on Agriculture and Life Sciences
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• v.29
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• pp.83-89
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• 2011

Various functional and useful components in Portulaca oleracea were extracted with ethanol and the optimum solvent conditions were set by monitoring of response surface methodology(RSM). A central composite design for optimization was applied to investigate the effects of the three independent variables of extraction temperature, ethanol concentration, and extraction time, on dependent variables including total phenolics, electron-donating ability, brown clolor and total flavonoids of Portulaca oleracea. The content of total phenol was essentially unaffected by extraction time or extraction temperature, but it was highly influenced by ethanol concentration. The maximum total phenol content was 31.70mg/mL obtained at 45.84% of ethanol concentration, $79.66^{\circ}C$, and after 2.67hr of extraction. Electron-donating ability (EDA) was affected by ethanol concentration and the maximum EDA was 74.67mg/mL at 52.95% ethanol concentration, $52.33^{\circ}C$ and 4.84hr of extration time. The browning color was rarely affected by extraction time but, it was highly influenced by ethanol concentration and extraction temperature. The maximum extent of browning color was obtained at 97.75% of ethanol concentraion, $65.88^{\circ}C$ and 2.93hr of extraction time. The content of total flavonoid was significantly influenced by extraction time, and the maximum total flavonoid level was 58.28mg/mL obtained at 96.62% ethanol concentration, $61.87^{\circ}C$ after 3.70hr of extraction. As a result, The optimal conditions for effective extraction were predicted as follows, 70.3% of ethanol concentration, $62.1^{\circ}C$ of extraction temperature and 3.3hr of extraction time.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.25-41
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• 2014

Recently, the number of social media users has increased rapidly because of the prevalence of smart devices. As a result, the amount of real-time data has been increasing exponentially, which, in turn, is generating more interest in using such data to create added value. For instance, several attempts are being made to analyze the relevant search keywords that are frequently used on new portal sites and the words that are regularly mentioned on various social media in order to identify social issues. The technique of "topic analysis" is employed in order to identify topics and themes from a large amount of text documents. As one of the most prevalent applications of topic analysis, the technique of issue tracking investigates changes in the social issues that are identified through topic analysis. Currently, traditional issue tracking is conducted by identifying the main topics of documents that cover an entire period at the same time and analyzing the occurrence of each topic by the period of occurrence. However, this traditional issue tracking approach has two limitations. First, when a new period is included, topic analysis must be repeated for all the documents of the entire period, rather than being conducted only on the new documents of the added period. This creates practical limitations in the form of significant time and cost burdens. Therefore, this traditional approach is difficult to apply in most applications that need to perform an analysis on the additional period. Second, the issue is not only generated and terminated constantly, but also one issue can sometimes be distributed into several issues or multiple issues can be integrated into one single issue. In other words, each issue is characterized by a life cycle that consists of the stages of creation, transition (merging and segmentation), and termination. The existing issue tracking methods do not address the connection and effect relationship between these issues. The purpose of this study is to overcome the two limitations of the existing issue tracking method, one being the limitation regarding the analysis method and the other being the limitation involving the lack of consideration of the changeability of the issues. Let us assume that we perform multiple topic analysis for each multiple period. Then it is essential to map issues of different periods in order to trace trend of issues. However, it is not easy to discover connection between issues of different periods because the issues derived for each period mutually contain heterogeneity. In this study, to overcome these limitations without having to analyze the entire period's documents simultaneously, the analysis can be performed independently for each period. In addition, we performed issue mapping to link the identified issues of each period. An integrated approach on each details period was presented, and the issue flow of the entire integrated period was depicted in this study. Thus, as the entire process of the issue life cycle, including the stages of creation, transition (merging and segmentation), and extinction, is identified and examined systematically, the changeability of the issues was analyzed in this study. The proposed methodology is highly efficient in terms of time and cost, as it sufficiently considered the changeability of the issues. Further, the results of this study can be used to adapt the methodology to a practical situation. By applying the proposed methodology to actual Internet news, the potential practical applications of the proposed methodology are analyzed. Consequently, the proposed methodology was able to extend the period of the analysis and it could follow the course of progress of each issue's life cycle. Further, this methodology can facilitate a clearer understanding of complex social phenomena using topic analysis.

• Korea and Global Affairs
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• v.1 no.1
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• pp.71-96
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• 2017

This study speculates on responses to the nuclear threats of North Korea and mutual assistance and cooperation between South Korea, the U.S. and China for the unification of the Korean Peninsula. As for the North Koreas nuclear issue and unification of the Korean Peninsula, South Korea is the subject of national division, the U.S. is a responsible country in international issues and does not have diplomatic ties with North Korea. China is a traditional socialist nation and a supporter of North Korea. As North Korea's strategic weapons including nuclear weapons and ballistic missiles are international issues, to defend against Kim Jung-Eun's unexpected acts, the three countries should actively cooperate with each other and develop countermeasures. However, with respect to the road map of the North Koreas issue, there are subtle differences between the U.S. and China in recognition of and sanctions against North Korea as a resolution of the U..N. Security Council. The U.S. has continued a deterrence policy and sanctions against North Korea based on joint threats between South Korea and the U.S. while China has showed a negative position in the process of solving the North Korean nuclear issue because of the unstable security derived from the U.S. 's intervention in the Korean peninsula. North Korea should change its diplomatic policy in a more concrete way towards world peace although it has continued trade of strategic weapons with Middle Eastern countries to maintain its political system. For example, to restart the summit talks and open multilateral security channels. Although the issue of unification of the Korean peninsula should be resolved by South and North Korea themselves, it is strange that South and North Korea depend on the logic of powerful countries for the resolution of a national problem. As for North Koreas nuclear and the Unification issues, peaceful solutions presented by South Korea seem more persuasive than the solution presented by North Korea which did not secure any international support. However, South Korea, the U.S. and China need to develop uni-directional two-tract strategies for sanctions against North Korea and talks with North Korea for peace on the Korean peninsula, and should continue to support the economic independence of North Korea.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.110-118
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• 2015

Borimsa Temple in Jangheung, one of the Goosanseonmoon of Shilla Dynasty, calls for a study in the field of landscape architecture because it has very significant elements in cultural and ecological landscaping aspects. This study examined the changes in landscaping elements of Borimsa Temple since the 17th century in order to newly recognize cultural landscaping value of space composition elements for traditional temple and to verify landscape architectural position. For research method, literatures such as Sajeonggi (事蹟記), Joongchanggi, a surveyed map by Fujishima Gaijiro in 1928 and Joseon Gojeogdobo (朝鮮古蹟圖譜) and modern documents including Borimsa Temple Precision Ground Survey Report and photographic records of National Archives of Korea and provincial governments were examined together with a field survey in order to trace changes in landscape elements such as buildings within the temple site, pond and temple forest. The results are as the following: First, for geographical locations of Borimsa Temple, it is located in an auspicious location and Shipyuknahansang and Cheonbul were placed in a supplementary purpose according to the contents of Bojoseonsatapbi. Compared to Namhwaseonsa Temple in China, it has a similar environmental composition but the fact that buildings were placed on platforms is a distinctive difference. Second, architectural landscape of Borimsa Temple went through the Japanese colonial era and Korean War and still going through changes today. Thus, there shall be some appropriate measures such as to establish an archive of past landscape data. Third, the contents of Borimsa Temple Sajeonggi suggests that the pond of Borimsa Temple had been in a indeterminate form with stones on the outer edge. Its name could have been Yongcheon (湧泉) according to the contents of Joongchanggi. Also, the current landscape, in comparison with past photographs, is a result of changes from surface raise occurred by ground reinforcement within the temple site. Fourth, Jangsaengpyoju (長生標柱) mentioned in Bojoseonsatapbi and Borimsa Temple Sajeonggi was thought to be the dried juniper tree in front of Daewoongbojeon, which can be found in past photographic documents but, it is now assumed to be Seokbihyeong (石碑形) considering the Gukjangsaeng and Hwangjangsaeng of Dogapsa Temple of the similar time period. Moreover, Hongsalmoon mentioned in Joongchanggi was established by King's order after the Manchu war of 1636 in praising of Buddhist monks those who had volunteered to fight for the country. Fifth, it is apparent in Borimsa Temple Joongchanggi that geomancy was a consideration in landscaping process of Borimsa Temple, and the record indicates that pine trees, bo trees and persimmon trees were planted. Sixth, tea tree forest was verified of its historical root that is Seongchailyeo from Unified Shilla through passing down of Jeong Yak-yong's Goojeunggoopo method and relevant documents of Seon Master Choui and Yi Yu-won. Seventh, nutmeg tree forest suggests that nutmegs were used in national ceremonies and for medical uses. The nutmeg tree forest was also verified of its role as Naehwasoorimdae (a forest built to prevent fire from spreading) through aerial photographs and placement of a forest reserve.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.51-62
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• 2012

Geumho-dong, Seoul, a redeveloped residential area, is located in the foothills of Mt. Eungbong. The geographical undulation, the composition of a large apartment complex, and the partial implementation of the redevelopment project have caused the severe physical and social disconnections in this area. In order to recover functioning in the disconnected community, this study pays attention to the regeneration of the open spaces as an everyday place and in the form a network system among those open spaces. Various types of the open spaces are classified into points or faces, 'bases' and linear 'paths' analyze the network status. More than half of the open space have connecting-distance of 500m or more. Furthermore, many areas are not even included in the service-area of the open spaces. Analysis of the connectivity and integration value using the axial map has carried out to check weak linkages and to choose the sections where additional bases are required. In addition, to improve the quality of the bases and the paths, a field investigation is conducted and problems are diagnosed. The network planning of the open spaces in Geumho-dong is established, ensuring the quality and quantity of bases and paths. The plan includes the construction of an additional major base in the central area and six secondary bases in other parts, and comes up with ways to improve the environment of underdeveloped secondary bases. In the neighborhood parks at Mt. Daehyun areas, the major path are added, and the environment of the paths is improved in certain areas. Because of the network planning, the connecting-distances between bases are reduced significantly, the connectivity and integration value of the area are increased, and the service areas of the open spaces cover the whole area properly. Although this study has some limitations such as the needs for the legal and institutional supports and difficulties of a quantitative indexing process, its significance lies in the suggestion of a more reasonable and practical plan for the overall network system by defining complex types of open spaces simply and clearly and by examining the organic relationships quantitatively and qualitatively.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.80-92
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• 2007

Forest fire is the dominant large-scale disturbance mechanism in the Korean temperate forest, and it strongly influences forest structure and function. Moreover burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. Vegetation rehabilitation may specifically vary according to burn severity after fire. To understand burn severity and process of vegetation rehabilitation at the damaged area after large-fire is required a lot of man powers and budgets. However the analysis of burn severity in the forest area using satellite imagery can acquire rapidly information and more objective results remotely in the large-fire area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. For classifying fire damaged area and analyzing burn severity of Samcheok fire area occurred in 2000, Cheongyang fire in 2002, and Yangyang fire in 2005 we utilized Normalized Burn Ratio(NBR) technique. The NBR is temporally differenced between pre- and post-fire datasets to determine the extent and degree of change detected from burning. In this paper we use pre- and post-fire imagery from the Landsat TM and ETM+ imagery to compute the NBR and evaluate large-scale patterns of burn severity at 30m spatial resolution. 65% in the Samcheok fire area, 91% in the Cheongyang fire area and 65% in the Yangyang fire area were corresponded to burn severity class above 'High'. Therefore the use of a remotely sensed Differenced Normalized Burn Ratio(${\Delta}NBR$) by RS and GIS allows for the burn severity to be quantified spatially by mapping damaged domain and burn severity across large-fire area.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

• Journal of Environmental Impact Assessment
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• v.27 no.4
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• pp.367-377
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• 2018

A cultural ecosystem service(CES), which is non-material benefit that human gains from ecosystem, has been recently further recognized as gross national income increases. Previous researches proposed to quantify the value of CES, which still remains as a challenging issue today due to its social and cultural subjectivity. This study proposes new way of assessing CES which is called Cultural Service Opportunity Spectrum(CSOS). CSOS is accessibility based CES assessment methodology for regional scale and it is designed to be applicable for any regions in Korea for supporting decision making process. CSOS employed public spatial data which are road network and population density map. In addition, the results of 'Rapid Assessment of Natural Assets' implemented by National Institute of Ecology, Korea were used as a complementary data. CSOS was applied to Namyangju-si and the methodology resulted in revealing specific areas with great accessibility to 'Natural Assets' in the region. Based on the results, the advantages and limitations of the methodology were discussed with regard to weighting three main factors and in contrast to Scenic Quality model and Recreation model of InVEST which have been commonly used for assessing CES today due to its convenience today.

• Korean Security Journal
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• no.14
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• pp.517-534
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• 2007

Since the beginning of human society, there have always been struggles and competitions for survival and prosperity, terrorism is not a recent phenomenon, however in modern times it has progressed to reflect the advances in civilization and power structures. At the time of the 9.11 terrorist attacks in the U.S. A., a new world order was in the process of being established after the breakdown of the Cold War era. The attacks drove both the Western and the Islamic worlds into heightened fear of terrorism and war, which threatened the quality of life of the whole mankind. Through two war campaigns against the Islamic world, it seems the U.S. has been pushing its own militaristic security road map of the Greater Middle East democratic initiative, justifying it as a means to retaliate and eradicate the terrorist threats towards themselves. However, with its five-year lopsided victories that cost the nation almost four thousand military casualties, and the war expenses that could match the Vietnam war, the U.S. does not yet seem to be totally emancipated from the fears of terrorism. Terrorism, in itself, is a means of resisting forced rules a form of alternative competition by the weak against the strong, and a way of expressing a dismissive response against dictatorial ideas or orders which allow for no normal changes. Intrinsically, the nature of terrorism is a reaction opposing power logics. Confronted with the absolute military power of the U.S., the Islamic strategies of terrorism have begun to rapidly evolve into a new stage. The new strategies take advantage of their civilization and circumstances, they train and inspire their front-line fighters on the Internet, and issue their orders through the clandestine network of the Al Qaeda operatives. These spontaneously generated strategies have been gained speed among the second, and third Islamic generations, many of whom are now spread throughout western societies. This represents a failure of the power-driven, one-sided overseas security initiatives by the U.S., and is creating a culture of fear and distrust in western societies. It is feared that the U.S. war campaigns have made the clash of religions far worse than before, and may ever lead to global ethnic separations and large-scale population movements. Eventually, it may result in the terrorist groups, enlarged and secretly supported by the huge sums of oil money, driving all mankind into a series of irreparable catastrophes.

• Asia pacific journal of information systems
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• v.22 no.4
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• pp.7-29
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• 2012

Smartphone and its applications (i.e. apps) are increasingly penetrating consumer markets. According to a recent report from Korea Communications Commission, nearly 50% of mobile subscribers in South Korea are smartphone users that accounts for over 25 million people. In particular, the importance of smartphone has risen as a geospatially-aware device that provides various location-based services (LBS) equipped with GPS capability. The popular LBS include map and navigation, traffic and transportation updates, shopping and coupon services, and location-sensitive social network services. Overall, the emerging location-based smartphone apps (LBA) offer significant value by providing greater connectivity, personalization, and information and entertainment in a location-specific context. Conversely, the rapid growth of LBA and their benefits have been accompanied by concerns over the collection and dissemination of individual users' personal information through ongoing tracking of their location, identity, preferences, and social behaviors. The majority of LBA users tend to agree and consent to the LBA provider's terms and privacy policy on use of location data to get the immediate services. This tendency further increases the potential risks of unprotected exposure of personal information and serious invasion and breaches of individual privacy. To address the complex issues surrounding LBA particularly from the user's behavioral perspective, this study applied the privacy calculus model (PCM) to explore the factors that influence the adoption of LBA. According to PCM, consumers are engaged in a dynamic adjustment process in which privacy risks are weighted against benefits of information disclosure. Consistent with the principal notion of PCM, we investigated how individual users make a risk-benefit assessment under which personalized service and locatability act as benefit-side factors and information privacy risks act as a risk-side factor accompanying LBA adoption. In addition, we consider the moderating role of trust on the service providers in the prohibiting effects of privacy risks on user intention to adopt LBA. Further we include perceived ease of use and usefulness as additional constructs to examine whether the technology acceptance model (TAM) can be applied in the context of LBA adoption. The research model with ten (10) hypotheses was tested using data gathered from 98 respondents through a quasi-experimental survey method. During the survey, each participant was asked to navigate the website where the experimental simulation of a LBA allows the participant to purchase time-and-location sensitive discounted tickets for nearby stores. Structural equations modeling using partial least square validated the instrument and the proposed model. The results showed that six (6) out of ten (10) hypotheses were supported. On the subject of the core PCM, H2 (locatability ${\rightarrow}$ intention to use LBA) and H3 (privacy risks ${\rightarrow}$ intention to use LBA) were supported, while H1 (personalization ${\rightarrow}$ intention to use LBA) was not supported. Further, we could not any interaction effects (personalization X privacy risks, H4 & locatability X privacy risks, H5) on the intention to use LBA. In terms of privacy risks and trust, as mentioned above we found the significant negative influence from privacy risks on intention to use (H3), but positive influence from trust, which supported H6 (trust ${\rightarrow}$ intention to use LBA). The moderating effect of trust on the negative relationship between privacy risks and intention to use LBA was tested and confirmed by supporting H7 (privacy risks X trust ${\rightarrow}$ intention to use LBA). The two hypotheses regarding to the TAM, including H8 (perceived ease of use ${\rightarrow}$ perceived usefulness) and H9 (perceived ease of use ${\rightarrow}$ intention to use LBA) were supported; however, H10 (perceived effectiveness ${\rightarrow}$ intention to use LBA) was not supported. Results of this study offer the following key findings and implications. First the application of PCM was found to be a good analysis framework in the context of LBA adoption. Many of the hypotheses in the model were confirmed and the high value of $R^2$ (i.,e., 51%) indicated a good fit of the model. In particular, locatability and privacy risks are found to be the appropriate PCM-based antecedent variables. Second, the existence of moderating effect of trust on service provider suggests that the same marginal change in the level of privacy risks may differentially influence the intention to use LBA. That is, while the privacy risks increasingly become important social issues and will negatively influence the intention to use LBA, it is critical for LBA providers to build consumer trust and confidence to successfully mitigate this negative impact. Lastly, we could not find sufficient evidence that the intention to use LBA is influenced by perceived usefulness, which has been very well supported in most previous TAM research. This may suggest that more future research should examine the validity of applying TAM and further extend or modify it in the context of LBA or other similar smartphone apps.