• International Journal of Contents
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• v.8 no.3
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• pp.79-82
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• 2012

In digital contents distribution environments, a user authentication is an important security primitive to allow only authenticated user to use right services by checking the validity of membership. For example, in Internet Protocol Television (IPTV) environments, it is required to provide an access control according to the policy of content provider. Remote user authentication and key agreement scheme is used to validate the contents accessibility of a user. We propose a novel user authentication scheme using smart cards providing a secure access to multimedia contents service. Each user is authenticated using a subset of attributes which are issued in the registration phase without revealing individual's identity. Our scheme provides the anonymous authentication and the various permissions according to the combination of attributes which are assigned to each user. In spite of more functionality, the result of performance analysis shows that the computation and communication cost is very low. Using this scheme, the security of contents distribution environments in the client-server model can be significantly improved.

• Journal of Agricultural Extension & Community Development
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• v.10 no.2
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• pp.211-227
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• 2003

According to the TRQ system created by WTO agreement on agriculture, Korea notified the WTO of the application of tariff rate quotas for 67 agricultural commodities(now, 63 commodities). Among these government administrate state-operated trade for 17 commodities. However, WTO/DDA negotiation will bring about lowering tariffs and increasing quantities of tariff quota. This study suggest the development programs corresponding WTO/DDA agriculture negotiation. First, from the viewpoint of the protection of domestic agriculture & improving transparency of agricultural import administration, the administration system of the state-operated trade will be necessary to be transformed for market oriented methods. Second, the administration system of the state-operated trade will be necessary to be rendered unified organization also. The current system of the state-operated trade shows the phenomena og many divergency. And third, The quantities of market access of FTA between Korea and Chile will be desirable to be administrate by state-operated trade. Because, according to diffusion of FTA treaties, the amount of market access quantities of FTA increase rapidly henceforth.

• Journal of Communications and Networks
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• v.15 no.1
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• pp.25-30
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• 2013

Uplink multicarrier code-division multiple-access (MC-CDMA) with equal gain combining (EGC) over Nakagami fading channels is considered. An improved expression which is a feasible alternative for the bit error rate (BER) performance evaluation of MC-CDMA signals is proposed. Simulated annealing algorithm is employed to obtain the optimum value of the coefficients belonging to the proposed expression. Numerical examples show that the performance curves computed by the improved expression are in good agreement with the results obtained by the exact expression. Thus, the proposed expression can improve the accuracy of BER performance evaluation that has been realized by the approximate expression.

• The Korean Journal of Air & Space Law and Policy
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• v.1
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• pp.125-146
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• 1989

This paper is examine the problems of U.S.-Korea Air Service Agreement and recommend some directions for its improvement under the rapidly changing circumstance and growing importance of Korean penisula. Since the provisional agreement of 1949, U.S. -Korea Air Service Agreement has consistently been favorable to U.S. side. Fair and equal opportunity is the principle and basis of the bilateral air agreement. Notwithstanding such principle, it is only the U.S. carriers who can freely enter into any market, under the discretion of business strategy, while Korean carrier can serve only three points including Honolulu. In an effort to recitify such serious imbalance, Korea continuousely requested additional rights and has given utmost efforts to accommodate requests made by U.S. carries without much success. When we review aviation market between Korea and U.S. under the present agreement, Korea is fully open to U.S. carries as they can connect from any or all points in the U.S. via any or all points in Korea and all points beyond Korea. Increased number of U.S. carriers are enjoying greater utilization of the opportunity accorded them. Four(4) U.S. carries now operate to Korea using thirteen(13) gateway points and about one hundred fifty(150) on-line points in the U.S. such imbalance can be well understood when we review the exchange of traffic rights between the U.S. and the Pacific rim countries. During the yeras following the 1978 agreement with Korea, the U.S. proceeded to sign liberal agreements with Thailand, Taiwan, Singapore and the Phillipines. In exchange, the U.S. granted the four Pacific rim countries substantially greater rights than were granted to Korea, although Korea was the first Asian nation to sign a pro-competitive aviation agreement which granted U.S. carriers unrestricted market access and pricing flexibility. Moreover, Korea ranks the 2nd trading and tourist partner to the U.S. among the Pacific rim countries (Japan is the largest partner to the U.S. in terms of both trade and tourist market). In this paper such problems in the Korea-U.S. Air Services Agreement are analyzed in terms of historical perspective, U.S. Aviation policy, imbalance status in detail cases, discrimination to Korea comparing to other Asian countries, and theoretical application. And further it discusses current aviation issues between Korea and U.S. such as the ratification of 1980 MOU and various doing business issues of U.S. carriers in Korea. Finally, this paper concludes the analysis and suggests some directions to improve and rectify the problems and imbalance of U.S.-Korea Air Services Agreement in question.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.1
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• pp.75-86
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• 2014

Demand for the femtocell is largely credited to the surge in a more always best connected communication conscious public. 3GPP defines new architecture and security requirement for Release 9 to deal with femtocell, Home eNode B referred as HeNB. In this paper, we analyze the HeNB security with respect to mutual authentication, access control, and secure key agreement. Our analysis pointed out that a number of security vulnerabilities have still not been addressed and solved by 3GPP technical specification. These include eavesdropping, man-in-the-middle attack, compromising subscriber access list, and masquerading as valid HeNB. To the best of our knowledge, any related research studying HeNB security was not published before. Towards this end, this paper proposes an improved authentication and key agreement mechanism for HeNB which adopts proxy-signature and proxy-signed proxy-signature. Through our elaborate analysis, we conclude that the proposed not only prevents the various security threats but also accomplishes minimum distance from use-tolerable authentication delay.

• Journal of Fisheries and Marine Sciences Education
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• v.18 no.2
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• pp.85-97
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• 2006

With extension of national jurisdiction over coastal living resources, new dimensions and objectives should be added to international cooperation in distant-water fisheries concepts. For distant-water fishing nations, Korea, joint exploitation of these resources is today considered not only as a way of producing additional income opportunities, but first of all as at least a partial solution to neutralization of harvesting limitations imposed on them in traditionally exploited fishing grounds.This paper explores the development of Korean distant-water fisheries agreements and reviews the various types of agreements currently in place and discusses the future of Korean distant-water fisheries agreements with third countries. The relationship between coastal States and fishing fleets from non-adjacent countries has been transformed since the 1980s. This was primarily a result of the declaration of Exclusive Economic Zones(EEZs) by many coastal states in the years leading up to the close of the negotiations of the UNCLOS in 1982. Significantly, by recognizing the right of coastal states to determine how their waters were to be exploited, UNCLOS provided a legal basis and economic motivation for the negotiation of access agreements between coastal states and distant-water fishing nations, KoreaThere is a real danger that Korean distant-water fisheries agreements could and do result in the adverse environmental impacts experienced in Korean coastal waters being transferred to third country water and consequently creating socio-economic problems for these third countries. Korean distant-water fisheries agreements with third countries have the potential to be a force for good if they are well managed and if the principals that will be applied within Korean coastal waters, through the reform of the distant-water fisheries policy, are applied equally upon third country waters.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.2
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• pp.61-72
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• 2009

This study aims to analyze the current situation of and issues in the structure of urban neighborhood parks and park facility installation in cities in Gyeonggi-do. Then, based on its findings, plans to improve the space structure of the parks were examined and suggested to raise the city environment improvement function and green area base function of urban parks and fully satisfy users' needs for pleasant rest, recreation and cultural activities. The findings showed that, within parks, the area of grass where access was restricted reached about 24.4% in average. In other words, only 75.6% of total park area could be freely used by park visitors. As for an improvement plan, the grass area where access is limited may be converted into a gras area that can be freely used to raise the park use area, which currently stands only at 75.6%, to 100%. The result of cross analysis through Chi-Square Test regarding lawn use as well as regarding (dis)agreement with reduction of lawn, based on the investigation of cognition, showed a significant agreement of park users with reduction of green areas. Therefore it is considered that lawn space must be reduced according the result of the analysis, to set up plans for facility space that would meet the desires of users. The analysis of user behaviors revealed that many of them used square spaces and walks; therefore it is considered that re-structuring of space is necessary according to local characteristics. This study also made some policy suggestion. urban parks must be a base of city green areas to counter climate changes. When developing a park creation plan, a user demand survey must be conducted in advance. In addition. grass construction methods should be improved to tolerate foot pressure.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.253-260
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• 2017

Authenticated key agreement in multi-server environments is one of very important security issues because only authorized user needs to access their data and services. To support this issue, numerous schemes have been proposed over recent years. Recently, Shin showed the security weaknesses in the previous scheme and proposed an improved scheme called SIAKAS to solve them. Unfortunately, this paper shows that SIAKAS is still weak against application server impersonation attack and could be traceable to attackers. To solve the problems in SIAKAS, we propose an untraceable authenticated key agreement scheme, denoted by UAKAS. UAKAS efficiently solves security and privacy issues in SIAKAS and the related schemes and could reduce the operation overhead at least 12% compared to them.

• Journal of the Earthquake Engineering Society of Korea
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• v.1 no.1
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• pp.31-39
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• 1997

This paper is on the vibration control of access floor on the frames of reinforced structure. In this study, the horizontal anti-vibration system using precise spring damper was developed and modeling and vibration analysis of the RC structure was performed for the control of horizontal vibration coused by machinery and worker's moving. Experiment was done in three cases, no damper at the RC structures, dampers connecting pedestal to pedestal and pedestal to the structure, for the investigation of the effect of the system on disigned RC structure. For each experiment, the occeleration responses on slab and access floor after giving impact wave and external vibration were measured. It was shown that the magnitude of resonance response of the system with dampers are smaller than without damper and the resonance peak also partly moved to low-frequency range. Furthermore. It was shown that the acceleration components of the system with domoers decreased greatly in high-frequency range and the system was very much effective especially for external vibration. In order to verify the anti-vibration effect of the developed system, the vibration analysis was also done for the system by using the finite element modelling. The analysis results was in good agreement with experimental results. Thus, It is concluded that this study is useful for the design of precise anti-vibration system and micro-vibration control of concrete structures.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.8
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• pp.1161-1170
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• 2013

Currently in 2013, a law that was drawn as a result of social agreement for personal information protection was enacted, and through several amendments, definite policy of written law and guideline were presented for definitive information protection in various fields of social business including IT field. Based on a series of social issues about the importance of personal information, a new access paradigm to personal information appeared. And from macroscopic access method called information protection, the necessity of technical access method came to the fore. Of course, it seems somewhat irrational to restrict all data in the form of personal information to a certain category of information until now. But in the deluge of information based on IT field, it is true that the part of checking the flow of personal information and selecting as security target has been standardized. But still there are cases in which it is difficult to routinely apply the five standardized flows of personal information Life-Cycle-collect, process, provide, store, and destroy-to information that all companies and organizations have. Therefore, the researcher proposes the standardized methodology by proposing the access control methodology for dualised hierarchical personal information Life-Cycle. The results of this research aim to provide practical data which makes optimal access control to personal information Life-Cycle possible.