• Environmental Engineering Research
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• v.11 no.4
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• pp.232-240
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• 2006

Polychlorinated naphthalenes (PCNs) formed along with dibenzo-p-dioxin and dibenzofuran products in the slow combustion of dichlorophenols (DCPs) at $600^{\circ}C$ were identified. Each DCP reactant produced a unique set of PCN products. Major PCN congeners observed in the experiments were consistent with products predicted from a mechanism involving an intermediate formed by ortho-ortho carbon coupling of phenoxy radicals; polychlorinated dibenzofurans (PCDFs) are formed from the same interemediate. Tautomerization of the intermediate and $H_2O$ elimination produces PCDFs; alternatively, CO elimination to form dihydrofulvalene and fusion produces naphthalenes. Only trace amounts of tetrachloronaphthalene congeners were formed, suggesting that the preferred PCN formation pathways from chlorinated phenols involve loss of chlorine. 3,4-DCP produced the largest yields of PCDF and PCN products with two or more chlorine substituents. 2,6-DCP did not produce tri- or tetra-chlorinated PCDF or PCN congeners. It did produce 1,8-DCN, however, which could not be explained.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.94-97
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• 2007

국내 CPS 수신환경에서 앙각별 DOP 및 측위 정밀도의 측정 ${\cdot}$ 분석을 통하여, DGPS 시스템의 24시간 안정적인 측위 정밀도를 제공할 수 있는 내륙 ${\cdot}$ 해양 기준국과 이용자 수신기의 적정 앙각을 제시하고자 한다.

• Journal of Environmental Science International
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• v.3 no.1
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• pp.65-76
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• 1994

The regiospecific potential for the reductive dechlorination of 2-, 3-, 4-, 2, 3-, 2, 4-, and 3, 4-chlorophenols (CPs) was studied in mono- and di-CP(DCP) adapted sediment slurries(10% solids). Freshwater sediments adapted to transform 2-CP dechlorinated all tested mono- and di-CPs except 4-CP without a lag period. Adaptation to 2-CP, thus, enhanced the onset of dechlorination of 3-CP and all ortho-substituted CPs tested. Sediment adapted to transform 3-CP dechlorinated all test CPs, except 4-CP and 2, 4-DCP, without a lag period. Sediment adapted to individual DCPs (2, 3-, 2, 4-, and 3, 4-DCP_ exhibited dechlorination(no lag phase) of 2-CP, 2, 3-, 2, 4-, and 3, 4-CDP. Interestingly, meta-cleavage of 3, 4-DCP in all tested adapted sediment occurred, while para-cleavage occurred in 3, 4-DCP adapted sediment. Sediment adapted to dechlorinate ortho and meta-chlorines exhibited a preference for meta following ortho-cleavage, but not for para-cleavage, while the preference for reductive dechlorination was ortho>meta>para for mono-CPs and ortho>para>meta for DCPs in unadapted freshwater anoxic sediments.

• The Journal of the Korea Contents Association
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• v.3 no.3
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• pp.40-46
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• 2003

In the paper, designed digital contents security module to check unlawfulness reproduction and distribution of digital contents. This paper applied Diffie-Hellman algorithm that use discrete logarithm and random number as primary for public key application to create encryption key that agree each other through communication channel between DCPS and HOST, and applied Triple DES repeat DES 3 times through 2 different encryption key that is selecting ANSI X9.17 that is key management standard, ISO 8732 and PEM(Privacy-Enhanced Mail) etc. by secondary protection for safe transmission of digital contents in transmission line. Designed security module consist of key exchange module, key derivation module and copy protection processing module. Digital contents security module that design in this thesis checks reproduction and distribution of digital contents by unauthenticated user through user certification function and digital contents encryption function, and protect digital contents transmission line.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.987-989
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• 2007

This paper describes a digital convergence platform(DCP) which is implemented based on the MPEG-21 multimedia framework. DCP is a newly proposed solution in this research for the convergence service of future home multimedia environment. DCP is a common platform designed to have the feature of reconfigurability, by means of S/W. which supports to run diverse digital multimedia services. A distributed peer to peer service and transaction model is also a new feature realized in DCP using the MPEG-21 multimedia framework. A prototype DCP is implemented to verify its functions of multimedia service and transactions. The developed DCPs are networked with IP clustering storage systems for the distributed service of multimedia. Successful streaming services of the MPEG-2/4 video and audio are verified with the implemented test-bed system of DCP.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.983-986
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• 2005

This paper describes a digital convergence platform(DCP) whice is implemented based on the MPEG-21 multimedia framework. The DCP is a newly proposed solution in this research for the convergence service of future home multimedia environment. The DCP is a common platform designed to have the feature of configurability, via means of S/W, which is needed for the convergence service of diverse digital media. A distributed peer to peer service and transaction model is also a new feature realized in the DCP using the MPEG-21 multimedia framework. A prototype DCP is implemented to verify its functions of multimedia service and transactions. The developed DCPs are networked with IP clustering storage systems for the distributed service of multimedia. Successful streaming services of the MPEG-2/4 video and audio are verified with the implemented test-bed system of the DCP.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.149-159
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• 2002

The objective of this study was to evaluate the formation characteristics of CBs and CPs from TCE, aliphatic compound. The experiment was carried out in a fixed reactor during 30 min under the oxidation condition at the range of temperature, 300~$700^{\circ}C$. MSWI fly ash was used as catalyst in this study. Total amount of CBs formed greater magnitude than that of CPs overall range of reaction temperature. It is proposed that the formation of CPs was caused from hydroxylation of CBs. According to increasing temperature to $600^{\circ}C$, the yield of CBs and CPs increased but significantly decreased at $700^{\circ}C$. It is suggested that decomposition rate was faster than formation rate at the high temperature. In the homologue distribution of CBs, DCBs were major products at 30$0^{\circ}C$ and the amount of higher chlorinated compound increased to $600^{\circ}C$. Because they were formed by chlorination of lower chlorinated compounds. In case of CPs, the amount of DCPs was 90% of total amounts in both thermal formation and catalytic reaction. On the other hand it was clearly observed that the chlorination rate in catalytic reaction was higher than in thermal formation with TCE only.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1577-1579
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• 1994

200-MW pulse modulators(total 11units) for the PLS linac employ the SCR phase control circuit. It controls 3-phase AC line voltage for the high-voltage DC power supply (DCPS, maximum of 25kVDC, 4.2A) which charges the pulse forming network(PFN). The PFN delivers 400kV, 500A, ESW $7.5{\mu}s$ pulse power to the 80-MW klystron amplifier tube. The SCR regulates 3-phase AC power and feeds to the high voltage transformer. Two different types of the transformer configurations namely ${\Delta}-{\Delta}$ and ${\Delta}-Y$, are alternatively installed to 11 modulator units for the suppression of harmonic noises. RC filters and reactors are also installed. Currently, approximately 110-kW of average AC power per unit is consumed at the normal operation level of the modulator with 30pps. This paper presents the operational characteristics of the high power pulse modulator, especially the experimental results of the AC line harmonic components generated by the operation of the high power pulse modulator to suppress the switching noises from the SCR and rectifying diode arrays.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.36-40
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• 2017

The launch operation for a space launch vehicle(SLV) is to be conducted by the systematic operation between SLV and the Technological Equipment(TE) such as the mechanical, fuel, and electrical ground support equipment at launch complex(LC). The basic source for the operation of the instruments in LC is the electrical power supply system, Technological Equipment Power Supply System(TEPSS), which is one of the Launch Control System. Thus TEPSS should supply the required electrical power to TE with reliability. In this paper, TEPSS which supplies operational electrical power to TE is introduced.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.3
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• pp.181-189
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• 2001

This paper describes the positioning accuracy of GPS moduls (KGP9800C, KiRyung) which need to record the operating position of fishing boat as realtime processing in order to develope auto recording system of fishing boat's operating information, and then it's positioning accuracy for DGPS receiver (MGP-100D, Shin-A) and DGPS beacon (GP-36, Furuno) were analyzed. Futhermore, it was examined the positioning error of the GPS module with processing algorithm to minimize the effect of the signal fluctuations. The results indicate that the positioning error is able to decrease 5m as 2drms, and such improvement of positioning performance for GPS module (KGP9800C) can be provide the basic design data in the development of the auto recording system of fishing boat's operating information.