• Journal of the Economic Geographical Society of Korea
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• v.20 no.2
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• pp.189-213
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• 2017

This study seeks to critically examine the significance and limits of the cluster adaptive cycle model for analysis of cluster evolution and to propose research issues for future analysis of cluster evolution based on this critical examination. Until the 1980s, research on industrial complexes including clusters was based on a 'static perspective' that focuses on the aspect of economic space at a specific point in time, but the research paradigm has recently shifted to a 'dynamic perspective' focusing on 'evolution' of 'complex adaptive systems'. As a result, the adaptive cycle model has attracted attention as an analysis tool of dynamically evolving clusters. However, the cluster adaptive cycle model has emerged by being appropriately modified and expanded according to the properties of the cluster and its evolution. The cluster adaptive cycle model is a comprehensive analysis framework that identifies the characteristics of cluster evolution in terms of resource accumulation, interdependence, and resilience and classifies cluster evolution paths into six different categories. Nevertheless, there is still a need for further discussion and supplementation in terms of theoretical and empirical research to expand and deepen the model. Therefore, research issues for future analysis of cluster evolution are to specify and elaborate the cluster evolution model, to emphasize the concept of resilience, and to verify the applicability and usefulness of the model through empirical research.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6C
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• pp.544-561
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• 2002

In this paper, we propose a new hybrid type of the routing protocol (Virtual Cluster-based Routing Protocol: VCRP) for mobile ad-hoc networks, based on a virtual cluster, which is defined as a narrow-sense network to exchange the basic information related to the routing among the adjacent nodes. This particular approach combines advantage of proactive routing protocol (PRP), which immediately provides the route collecting the network-wide topological and metric information, with that of reactive routing protocol, which relies on the route query packet to collect the route information on its way to the destination without exchanging any information between nodes. Furthermore, it also provides the back-up route as a byproduct, along with the optimal route, which leads to the VCBRP (Virtual Cluster-based Routing Protocol with Backup Route) establishing the alternative route immediately after a network topology is changed due to degradation of link quality and terminal mobility, Our simulation studies have shown that the proposed routing protocols are robust against dynamics of network topology while improving the performances of packet transfer delay, link failure ratio, and throughput over those of the existing routing protocols without much compromising the control overhead efficiency.

• Journal of the Korean Geographical Society
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• v.38 no.2
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• pp.206-223
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• 2003

Bays and caps represent the physical characteristics of Naepo area in Korea. And reclamation of tidal land presents a clue toward the understanding of regional identities and landscape changes in this area. Reclamation of tidal land in the Garorim bay that is representative of the physical geographies of Naepo area had trended toward 'the diffusion of salt ponds' during Joseon dynasty. Hereafter the Japanese imperialism, the reclamation had tumed to 'the reclamation of arable lands' by drainage. But, at the same time the land use of salt pond that had been the most appropriate strategy of adaptation for the ecological environments of this area has showed a sort of the geographical long-term durability. And the great landlords that had emerged during Japanese imperialism were the Yeom-han(鹽漢, laborers who engaged in salt production) in former times. They as a new local elites have played a leading role in the reclamation of tidal land and the making of regional landscape.

• The KIPS Transactions:PartD
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• v.15D no.2
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• pp.271-284
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• 2008

Self-healing is an approach to evaluating constraints defined in target system and to applying an appropriate strategy when violating he constrains. Today, the computing environment is very complex, so researches that endow a system with the self-healing's ability that recognizes problem arising in a target system are being an important issues. However, most of the existing researches are that self-healing developers need much effort and time to analyze and model constraints. Thus, this paper proposes an automated approach to determine problem arising in external and internal system environment. The approach proposes: 1) Specifying the target system through the models created in design phase of target system. 2) Automatically creating constraints for external and internal system environment, by using the specified contents. 3) Deriving a dependency model of a component based on the created internal state rule. 4) Translating the constraints and dependency model into code evaluating behaviors of the target system, and determinating problem level. 5) Monitoring an internal and external status of system based on the level of problem determination, and applying self-healing strategy when detecting abnormal state caused in the target system. Through these, we can reduce the efforts of self-healing developers to analyze target system, and heal rapidly not only abnormal behavior of target system regarding external and internal problem, but also failure such as system break down into normal state. To evaluate the proposed approach, through video conference system, we verify an effectiveness of our approach by comparing proposed approach's self-healing activities with those of the existing approach.

• Journal of Technology Innovation
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• v.29 no.4
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• pp.95-124
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• 2021

Startups play an important role in economic growth and job creation in niche markets, thus governments regularly expand their research and development(R&D) budgets accordingly. As stratups are more dependent on governments to compensate for insufficient resources and capabilities than large and medium-sized companies, trust in government policies will be important. In this study, we analyzed the impact of startups' trust in government R&D policies on innovation performance. There were three major results. The first result is that government R&D investments in startups increase innovation performance in the manufacturing and high-technology industries but did not affect other industries. The second result is that trust in government R&D policies increased innovation in high-and medium-high technology and manufacturing industries. The third result is that trust in government R&D policies affects innovation before, during, and after evaluation of support process. We analyzed the importance of trust to the effectiveness of government R&D support to determine how to effectively provide it. The results show that governments need to differentiate the types of R&D support they provide according to the target firm's technology level and whether they are a manufacturing company and that appropriate R&D support mechanism should be developed for low-technology and non-manufacturing companies. Finally, governments should allocate resources and make fair and transparent decisions to help companies grow, not to better supervise them.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.28-55
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• 2010

Currently, the natural monument system of Korea for naming and designation of natural monuments is based on "Chosun Natural Monument Conservation Acts for Treasure, Ancient Landmark, and Natural Beauty" enacted in 1934 during Japanese colonization period. The framework of natural monument system is still in effect, which is pointed out as a problem. The Dangsan forests and Bibo forests are Korean traditional cultural resources representing countryside of Korea. Cultural Heritage Administration follows and relies on the 'Limsu of Chosun' (1938), a report written by a Japanese, for naming and classification of natural monuments. A Dangsan forest at Yesong-ri was named "Yesong-ri evergreen forest" in 1938. They followed the naming system of "evergeen forest" until today. The objective of this study is to review the issues and problems of 'Limsu of Chosun' and natural monument naming system begun during Japanese occupation period, and suggest an alternative to the current situation where naming natural monument accordingly without discretion. Eighteen dangsan forests bibo forests were selected for examination and analysis. The names of the dangsan forests bibo forests were evaluated to find out whether various aspects of the forests are reflected in the name. The study suggests that many forests and old trees designated as natural monument should be named as "~Dangsan forest", "~Dangsan forest Bibo forest", or "~Dangsan tree" with consistency accordingly. The new names will bring a momentum to overcome the limitation of natural monument naming system continued since Japanese occupation period, and also enhance the value of Dangsan forests and Bibo forests as Korean traditional and cultural landscapes.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.627-642
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• 2022

The world's long reliance on fossil fuels (e.g., oil, coal, and natural gas) is severely changing its environment and climate. Energy research has focused on developing hydrogen as the most promising energy carrier and a key technology for sustainable energy development. Hydrogen can be classified as gray, blue, green, and otherwise according to the raw materials and methods used for production and processing. For the development of hydrogen energy, geologists are attempting to identify the mechanism of abiotic hydrogen generation by serpentinization or hydrothermal alteration. Teams in the United States, France, and Australia have researched laboratory-scale hydrogen production through water-rock interactions under various conditions, whereas there has been almost no research on abiotic hydrogen in South Korea. This paper reviews the current state of international research on hydrothermal alteration and offers suggestions for future investigations of abiotic hydrogen production in South Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.958-965
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• 2016

The objective of this study was to evaluate the antioxidant activity of green tea seed shell as an industrial byproduct. Green tea seed shell extract (GTSSE) was obtained by ethanol extraction, and the yield was $1.4{\pm}0.22%$. The radical scavenging activities [1,1-diphenyl-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)], xanthine oxidase inhibition activity, and reducing power of GTSSE dose-dependently increased. To estimate the neuroprotective effect of GTSSE, viability was tested in HT22 mouse hippocampal cells. GTSSE treatment induced cytotoxicity at a concentration higher than $100{\mu}g/mL$ but not at a concentration lower than $50{\mu}g/mL$. Using this optimal concentration range, GTSSE treatment significantly increased cell viability in $H_2O_2$-treated HT22 cells. Further, GTSSE treatment increased superoxide dismutase activity and decreased the malonaldehyde level, a product of lipid peroxidation, in HT22 cells. Therefore, these results indicate that green tea seed shell extract may be useful for the development of antioxidant materials and have potential activity to prevent and treat neuro-degenerative diseases such as Alzheimer's disease.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.267-273
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• 2018

Matricaria chamomilla L. has been used as a bath agent in Europe because of its sterilization effect on the skin. Flowers contain terpenes, flavonoids are effective in relieving inflammation. Matricaria chamomilla L. has been reported to have various drug efficacies such as sedation, anti-diabetic effect and anti-arthritic effect, but there is little research on the scientific efficacy of whitening effect. The purpose of this study was to examine the whitening effect of Matricaria chamomilla L. extract and to investigate the mechanism of inhibition of melanogenesis. The extracts were used to determine tyrosinase inhibitory activity. The tyrosinase inhibitory activity of extracts was ineffective for water extract but in 60% ethanol extract was shown in a concentration-dependent manner. B16F10 melanoma cell was measured using a powder obtained by lyophilization of 60% ethanol extract. The toxicity was observed at a concentration of $75{\mu}g/mL$. And concentration range was selected to be at most $50{\mu}g/mL$. The effect of tyrosinase, MITF, TRP-1 and TRP-2 on the expression of melanin protein was investigated in melanoma cells of B16F10 melanoma cells. As a result, it was confirmed that as the concentration of the extract increased, the melanogenesis level decreased and the protein expression level also decreased in a concentration dependent manner. Therefore, it was concluded that Matricaria chamomilla L. extract inhibited melanogenesis in cells. Based on the above results, it is expected that it will be used as a useful basic data for industrialization of whitening functional food of Matricaria chamomilla L.

• The KIPS Transactions:PartB
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• v.18B no.6
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• pp.405-414
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• 2011

Korean grammar checkers typically detect context-dependent errors by employing heuristic rules that are manually formulated by a language expert. These rules are appended each time a new error pattern is detected. However, such grammar checkers are not consistent. In order to resolve this shortcoming, we propose new method for generalizing error decision rules to detect the above errors. For this purpose, we use an existing thesaurus KorLex, which is the Korean version of Princeton WordNet. KorLex has hierarchical word senses for nouns, but does not contain any information about the relationships between cases in a sentence. Through the Tree Cut Model and the MDL(minimum description length) model based on information theory, we extract noun classes from KorLex and generalize error decision rules from these noun classes. In order to verify the accuracy of the new method in an experiment, we extracted nouns used as an object of the four predicates usually confused from a large corpus, and subsequently extracted noun classes from these nouns. We found that the number of error decision rules generalized from these noun classes has decreased to about 64.8%. In conclusion, the precision of our grammar checker exceeds that of conventional ones by 6.2%.