• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.669-685
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• 2003

Nowadays mobile phones and PDAs are part and parcel of our lives. By carrying a portable mobile device with us all the time we are already living in partial Pervasive Computing Environment (PCE) that is waiting to be exploited very soon. One of the advantages of pervasive computing is that it strongly supports the deployment of Location-Based Service(s) (LBSs). In PCE, there would be many competitive service providers (SPs) trying to sell different or similar LBSs to users. In order to reserve a particular service, it becomes very difficult for a low-computing and resource-poor mobile device to handle many such SPs at a time, and to identify and securely communicate with only genuine ones. Our paper establishes a convincing trust model through which secure job delegation is accomplished. Secure Job delegation and cost effective cryptographic techniques largely help in reducing the burden on the mobile device to securely communicate with trusted SPs. Our protocol also provides users privacy protection, replay protection, entity authentication, and message authentication, integrity, and confidentiality. This paper explains our protocol by suggesting one of the LBSs namely“Secure Automated Taxi Calling Service”.

• Journal of Korea Multimedia Society
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• v.18 no.1
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• pp.35-41
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• 2015

SDN(Software Defined Networking) has been considered as a new future computer network architecture and DDoS(Distributed Denial of Service) is the biggest threat in the network security. In SDN architecture, we present the technique to defend the DDoS SYN Flooding attack that is one of the DDoS attack method. First, we monitor the Backlog queue in order to reduce the unnecessary monitoring resources. If the Backlog queue of the certain server is occupied over 70%, the sFlow performs packet sampling with the server address as the destination address. To distinguish between the attacker and the normal user, we use the source address. We decide the SYN packet threshold using the remaining Backlog queue that possible to allow the number of connections. If certain sources address send the SYN packet over the threshold, we judge that this address is attacker. The controller will modify the flow table entry to block attack traffics. By using this method, we reduce the resource consumption about the unnecessary monitoring and the protection range is expanded to all switches. The result achieved from our experiment show that we can prevent the SYN Flooding attack before the Backlog queue is fully occupied.

• Environmental and Resource Economics Review
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• v.14 no.4
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• pp.893-921
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• 2005

In this study, we try to find out the effect of private companies' environmental protection activities on the labor demand of companies in Korea manufacturing industries with empirical practice from 1992 to 2002. One of the main difficulties in this empirical work is to identify the effect of environmental protection activities on the labor demand, because the effect can be mixed with the effect of traditional production technologies on the labor demand. We follow the suggestion of Morgenstern et al. (2002) to identify the effect but which is not enough because of endogeneity between the production technology improvement and pollution reduction. So we propose a Fixed-effect Instrumental Variable estimation method as an estimation strategy. The estimation results support the positive relationship between the labor demand increase and the increase in pollution abatement costs. Therefore, we can conclude that the environmental protection activites of Korea manufacturing industries from 1992 to 2002 can help job creation without making a big burden for business activities when we consider the share of pollution abatement costs among total production costs is around 1% during that time.

• Environmental and Resource Economics Review
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• v.22 no.1
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• pp.127-145
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• 2013

This study estimates the economic impact of sea-level rise on Jeju island and suggests the optimal protection level based on the FUND model. There exist a number of studies that estimate the impacts of sea-level rise on global scale, but their results are of limited use for local scale such as Korea. Therefore, this study applies some specific indicators and data of Korea into to FUND model for deriving site specific estimates. The results show that 2.01%~2.25% of land could be inundated by sea-level rise until 2100. The value of affected land is about 6.4%~7.2% of total land value. The discrepancy between the figures indicates that the area affected by sea-level rise is much more valuable than the rest of Jeju island. The optimal protection level in Jeju city is higher than that in Seguipo city, even though the coastal length of Jeju city is longer than that of Seguipo. This is due to the fact that the economic value of Jeju city is much higher than that of Seoguipo city.

• Korean Journal of Pharmacognosy
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• v.47 no.1
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• pp.49-54
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• 2016

In our search for natural products affecting blood circulation, the n-butanol fraction from whole plant of Glehnia littoralis Fr. Schm. (GLB) improved blood lipid parameters, and ameliorated obesity in high-fat-diet (HFD)-fed C57BL/6 mouse model. Hyperlipidemia was induced by high-fat-diet for 4 weeks, and then GLB was orally administrated with 400 mg/kg/day for 4 weeks. GLB-treated group showed that the gain in body weight was significantly attenuated, the levels of total cholesterol and triglyceride significantly lowered on blood chemical analysis, and significantly prolonged the mice bleeding time when compared with those of HFD control group. Concomitantly, phytochemical composition of GLB was investigated by HPLC-hyphenated spectroscopy, and two major phenolic compounds, rutin and chlorogenic acid were identified in the GLB. Taken together, these results indicate that GLB has cardiovascular protective effects and could be a natural medicine candidate for the prevention of cardiovascular disease.

• Journal of Korea Water Resources Association
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• v.53 no.spc1
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• pp.827-832
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• 2020

The catchment management experiences of the Evian natural mineral water (NMW) bottling company were reviewed. Evian is among the leading brands of bottled NMW in France, exporting worldwide and becoming a role model for companies in many countries due to its long-term experiences in sustainably managing NMW source areas. Experiences of bottled water companies in France show that they are incessantly moving forward with proactive and advanced ideas to meet environmental challenges. For business sustainability, companies are dedicated to improving their environmental performance through effective and planned resource management. Evian has been working with the local community in a spirit of co-ownership to invent and preserve the water resource and fulfill its ambition of sustainable industrial functioning. The partnership aims to balance the protection of the NMW resource and sustainable agricultural development within the catchment.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.105-131
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• 2015

This study was carried out to investigate the flora of Gyodongdo island (Ganghwa-gun). The vascular plants from 11 field surveys were revealed to belong to a total of 629 taxa; 118 families, 364 genera, 561 species, 5 subspecies, 53 varieties, 7 forms and 3 hybrids. 184 taxa were the first records from this region. The plants in Gyodongdo island are composed of the deciduous broad-leaved and conifer-mixed forests which are the common ones in the middle part of the Korean Peninsula. Five taxa of Korean endemic plants such as Clematis brachyura Maxim., Viola seoulensis Nakai, Populus ${\times}$ tomentiglandulosa T. B. Lee, Forsythia koreana (Rehder) Nakai and Hemerocallis hakuunensis Nakai were collected. Endangered wild plants designated by the law called 'Protection Law for Endangered wild fauna and flora' were one taxon. The red list plants according to IUCN valuation basis were examined for 13 taxa; endangered (EN) species of Prunus yedoensis Matsum., Vulnerable (VU) species of both Utricularia pilosa (Makino) Makino and Iris ruthenica var. nana Maxim., Near Threatened (NT) species of Senecio argunensis Turcz., Least Concern (LC) species of Platycladus orientalis (L.) Franco, Potentilla discolor Bunge, Limnophila sessiliflora (Vahl) Blume, Acorus calamus L., Phacelurus latifolius (Steud.) Ohwi, Pseudoraphis ukishiba Ohwi, Belamcanda chinensis (L.) DC., and Not Evaluate (NE) species of both Astragalus sikokianus Nakai and Potamogeton oxyphyllus Miq. The floristic regional indicator plants found in this area were a total of 47 taxa comprising three taxa of grade V, four taxa of grade IV, nine taxa of grade III, 10 taxa of grade II, and 21 taxa of grade I. The naturalized plants were identified as 62 taxa and the percentage of naturalized index (NI) was 9.9 % and the percentage of urbanization index (UI) was 19.3 %, respectively. Furthermore, hemicryptophytes (28 %), therophytes (26 %), hydrophytes (13 %) and geophyte (12 %) showed high proportional ratio in life form spectrum.

• Journal of Haehwa Medicine
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• v.12 no.2
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• pp.235-244
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• 2004

WIPO international government committee will finish to develop toolkit for making documentation on discussions of intellectual property protection with TK, GR until the late 2003. As they construct DB of TK, GR, it becomes in a hurry to construct DB of TK information in Korea. We looked into application of copyright in force and a lot of problems in terms of analyzing medical books in the resent condition or protecting them in Korea. There are 29 kinds which have been lost, 12 kinds which could have read in parts, 136 kinds which have been existed of Korean medical books before 1900. There are also a lot of medical books which have been published after 1900 and still are unpublished. It would be 406 medical books from China totally, 111 kinds from Chosun Dynasty version, 134 kinds from Euybangeuchui, 225 kinds from Hyangyackjibsungbang, 78 kinds from Dongeuybogam. We consider to know whether Korean medical books could been applied to the copyright in force or not in accordance with discussions of WIPO on the period, subject(author), contents of protection. If it is applied to the copyright in force, it will be decided to revise according to discussions of WIPO. On the other hand, the problem which is occurred to protect Korean medical books is friction with China as importing their medical books, to find our medical books actively which has been unpublished. Finally, We have to revise administration and intellectual property standards or protect our medical books by making new administration laws.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.587-613
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• 1999

Environmental problems such as global climate change, depletion, ocean and air pollution, and resource degradation-compounded by an expanding world population-respect no border and threaten the health, prosperity and jobs of all mankind. Our efforts to promote democracy, free trade, and stability in the world will fall short unless people have a livable environment. We have an enormous stake in the management of the world's resources. By increasing demand for timber, natural gas, coal and consumer's goods have destroyed the grounds for living. Greenhouse gas emissions anywhere in the world have threatened coastal communities, and then changed the Earth's climate system. The burning of coal, oil, and other fossil fuels is increasing substantially the concentration of heat-trapping gasses such as carbon dioxide, methane, and nitrous oxide in our air. The earth's temperature and sea levels are rising as a result. Since 1972 there has been a marked growth in the number and scope of environmental treaties. In particular, after the 1992 Rio Conference, international legal instruments became more concentrated on addressing environment within the context of sustainable development and incorporated a number of new concepts and innovative approaches. A preliminary analysis of recent conventions and in particular those associated with the Rio Conference indicates various ideas, concepts and principles which have come to the fore including sustainable development, equity, common concern of humankind, common but differentiated responsibilities and global partnership. However, international trade also has an environmental impact which must be minimized or countered. Positive measures are to be preferred to achieve environmental goals, but where trade provisions are necessary, they should be appropriately used within environmental conventions to facilitate the reduction and limitation of the negative impacts of trade and to enhance the complementarity of the multilateral trade regime with the imperatives of environmental protection, in the interests of environmental protection and sustainable development generally. The international community has to recognize and endorse this need to achieve complementarity between trade and environment issues.

• Smart Structures and Systems
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• v.26 no.4
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• pp.435-449
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• 2020

To effectively extract the vast wind resource, offshore wind turbines are designed with large rotor and slender tower, which makes them vulnerable to external vibration sources such as wind and wave loads. Substantial research efforts have been devoted to mitigate the unwanted vibrations of offshore wind turbines to ensure their serviceability and safety in the normal working condition. However, most previous studies investigated the vibration control of wind turbines in one direction only, i.e., either the out-of-plane or in-plane direction. In reality, wind turbines inevitably vibrate in both directions when they are subjected to the external excitations. The studies on both the in-plane and out-of-plane vibration control of wind turbines are, however, scarce. In the present study, the NREL 5 MW wind turbine is taken as an example, a detailed three-dimensional (3D) Finite Element (FE) model of the wind turbine is developed in ABAQUS. To simultaneously control the in-plane and out-of-plane vibrations induced by the combined wind and wave loads, another carefully designed (i.e., tuned) spring and dashpot are added to the perpendicular direction of each Tuned Mass Damper (TMD) system that is used to control the vibrations of the tower and blades in one particular direction. With this simple modification, a bi-directional TMD system is formed and the vibrations in both the out-of-plane and in-plane directions are simultaneously suppressed. To examine the control effectiveness, the responses of the wind turbine without control, with separate TMD system and the proposed bi-directional TMD system are calculated and compared. Numerical results show that the bi-directional TMD system can simultaneously control the out-of-plane and in-plane vibrations of the wind turbine without changing too much of the conventional design of the control system. The bi-directional control system therefore could be a cost-effective solution to mitigate the bi-directional vibrations of offshore wind turbines.