• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.4
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• pp.584-590
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• 2013

Depending on the operating characteristics, track circuit is installed for the purpose of control directly or indirectly of the signal device, point switch machine and other security device. These are mainly used for train detection, transmission of information, broken train detection and transmission of return current. Especially, the return current is related to signal system, power system and catenary line, and track circuit systems. It is one of the most important component shall be dealt for the safety of track side staff and for the protection of railway-related electrical system according to electrification. Therefore, an accurate analysis of the return current is needed to prevent the return current unbalance and the system induced disorder and failure due to an over current condition. Also, if the malfunction occurred by the return current harmonics, it can cause problems including train operation interruption. In this paper, we presented measurement and analysis method at return current and it's harmonics by train operation. By the test criteria, we evaluated for safety. Hereafter, it is expected to contribute to the field associated with it.

• The Korean Journal of Applied Statistics
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• v.13 no.2
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• pp.297-306
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• 2000

Many users have made the most often use of the SAS system in statistical data analysis all over the world. But it is difficult to use the grand procedures and language of the SAS system. Therefore the side of program development has changed in the graphic-oriented and menu-centered way like SASj ASSIST, SASjINSICHT after a version 6.08 turned into the Window environment. A biplots is a multivariate data analysis technique that graphically describes both relationships among the multidimensional observations and relationships among the variables. But there were not the procedure and graphic interface for a biplots algorithm in the SAS system. In this paper, there are two objects. First, we supply users with the convenience of the environment of CLI, which is constructed with SASj AF and SCL, to solve the problem that we have programed a biplots algorithm with the SASjIML one by one. Second, we reflect the current of the Information Age which means the spread of various kinds of system construction to extract useful information from data with the help of the development of hardware and software.

• Journal of Agricultural Extension & Community Development
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• v.13 no.2
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• pp.375-384
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• 2006

농업－공동체 임업은 토지－나무－인간 사이의 관계를 폭넓게 포함하고 있으나 이 논문에서는 농업－공동체 임업활동이 베트남의 산지의 지속가능한 이용에 초점을 두고 있다. 농업－공동체 임업(AF와 CF)은 베트남에서 시급한 국가우선사항이 된 개발과 보전을 함께 고려할 수 있는 기능을 지닌 것으로 받아드려지고 있다. 베트남에서 AF와 CF를 동시에 지원할 수 있는 자원은 한정되어 있으며, 제약 사항은 위협적이고 시급한 상황이고, 황폐화가 진행될수록 복원은 어려워지는데, 농업의 생산성 감소에 따른 산촌주민들의 가족 부양을 위한 생태계 파괴도 가속화되고 있는 것으로 조사되었다. 이 연구는 농업－공동체 임업활동이 베트남의 산지 자원의 지속가능한 이용에 있어서의 연관된 문제들, 발전에의 제한요인, 특히 정책 제한요인을 분석하고 베트남 농업－공동체 임업 개발의 방향을 제시하고자 하였다.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.54-60
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• 1999

Three different types of lab-scale anaerobic bioreactors, AF and two-stage ASBF-PR and ASBF-SP, were evaluated in treating swine wastewater by operating at $1{\sim}2$ days of hydraulic retention time with increasing organic loading rate upto 6.3 $kg-COD/m^3{\cdot}d$ at $35^{\circ}C$. Seeding the anaerobic bioreactors with waste anaerobic digester sludge from a municipal wastewater treatment plant was effective and a 40-day acclimation period was required for steady-state operation. Three anaerobic bioreactors were effective in treating swine wastewater with COD removal efficiency of $66.4{\sim}84.9$% and biogas production rate of $0.333{\sim}0.796m^3/kg-COD_{removed}{\cdot}d$. Increases of organic loading rate by increasing influent COD concentration and/or decreasing hydraulic retention time caused decreases in COD removal efficiency and increases in biogas production rate. At relatively high organic loading rate employed in this study, the treatment efficiency of AF and ASBF-PR were similar but superior than that of ASBF-SP, indicating that porosity and pore size of the media packed in the bioreactors are more important factors contributing the performance of to bioreactors than specific surface area of the media. TKN in swine wastewater must be removed prior to the anaerobic processes when anaerobic process is considered as a major treatment process since influent TKN concentration of $1,540{\sim}1,870mg/L$ to the bioreactors adversely affect the activity of methanogenic bacteria, resulting in decreases of treatment efficiency and biogas production rate by 50%.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1116-1122
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• 2009

ATS(Automatic Train Stop) system makes train stop when it runs over the speed limit and ensure the safe operation of train. Seoul Metro line 2 in Korea, which started its passenger service in 1982, has adopted ATS system for its signaling system. The ATS system has only a train stop function at the time of emergency, and Seoul Metro is planning to replaced them with ATC(Automatic Train Control)/ATO(Automatic Train Operation) system which can provide the dedicated speed control for headway reduction and automatic operation of train. Until all the ATS system is replaced with the new ATC system, both systems are to operate simultaneously at the same metro line. In this situation, ATS system sometimes reveals improper operation: train stops suddenly without any obstacles in front of it. These emergency stops cause interruption of passenger service, and abnormal abrasion of wheels and rail. This paper makes it clear that these interruptions are caused by EMI phenomena between ATS on-board device and ATC wayside device : Signal current flowing in AF track circuit of ATC is turn out to be a EMI source that prevent normal operation of the ATS on-board device. Although the two systems have different frequency-ranges (ATS system has frequency range between $78{\sim}130$[kHz] and ATC system has frequency range between $9.5{\sim}16.5$[kHz]), it turned out that EMI phenomena appears between the both systems. This is investigated by measuring the output signal from ATS on-board device passing over ATC wayside device. The FFT(Fast Fourier Transform) analysis of the signal reveals that AF track circuit signal is transmitted to the ATS on-board device and induce noise causing improper operation. The countermeasures to the EMI phenomena are examined in three ways; blocking EMI transmission, enforcement of EMS (Electromagnetic Susceptibility) of ATS on-board device, and blocking the EMI source. It is suggested that the practical solution be blocking EMI source temporarily, that is breaking AF track circuit signal when the trains with ATS on-board device pass over it. To this purpose, TODS(Train Occupation Detection System) is developed, and has made a success in preventing the EMI problem of Seoul Metro line 2.

• Journal of fish pathology
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• v.17 no.2
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• pp.91-98
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• 2004

This study was performed for the identification of Streptococcus sp. from cultured flounders (Paralichthys olivaceus) showing streptococcosis in the Jeju island. We isolated 10 strains of Streptococcus iniae from the cultured olive flounders with streptococcosis. Isolated strains were identified in S. iniae since they have formed the expected band through performing PCR assay using specific primers, Sin-1 (5'-CTAGAGTACACATGTACT(AGCT)AAG-3') and Sin-2 (5'-GGATTTTCCACTCCCATTAC-3'). In addition to 16S-23S rRNA intergenic spacers (ISR), operon structure of isolated strains showed that all strains had three 16S-23S rRNA ISR band patterns. The 16S-23S rRNA ISR sequence of isolated strains showed 96% sequence identity with S. iniae (GenBank accession number AF 048773). This paper is the first report that S. iniae is associated with streptococcosis of Olive flounder in Korea.

• 한국경영정보학회:학술대회논문집
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• 2008.06a
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• pp.615-619
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• 2008

손자병법은 춘추 시대 오나라 왕 합려를 섬기던 손무(孫武)가 쓴 병법서로 전체 13편으로 구성되어 있다. 손자병법은 단순한 병법서가 아니라 정치, 기업경영, 처세 등 여러 분야에 활용되고 있다. 본 논문에서는 정보시스템의 효율적 도입 및 운영 등에 관한 법률(ITA법안)로 2006년부터 각 공공기관에서 도입이 추진 중인 정보기술아키텍처의 도입 의의와 발전 방향을 손자병법에 입각해서 분석해 본다.

• Defense and Technology
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• no.6 s.280
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• pp.50-63
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• 2002

한국군도 지금시점에서는 선진국의 C4ISR AF 소요공학 기법 같은 것들을 도입하여 한국적 정보체계 구축 시 전군적 통합 정보체계가 건설될 수 있도록 상세한 수준의 정보화소요공학 연구 및 적용을 하여야할 시기가 되었다고 판단된다. 따라서 전군 통합 정보체계가 구축되어질 수 있도록 하기 위해서 사업 초기단계에서 정보체계의 사업관리자, 소요 제기자, 체계 분석자, 체계 개발자들에게 가장 중요하고 필수적인 소요제기기법인 전군 통합 정보기술 아키텍쳐 프레임워크(ITAF) 기법의 적용 필요성을 소개한다.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.65-67
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• 2003

This paper proposes the cost analysis on the energy efficient equipment when this equipment is participated in the demand-side bidding. Conventional demand-side bidding is exercised through load re-distribution. However if this load reduction is exercised by the use of high efficient equipment, its effect will be assumed to be more economical. This paper analyses this cost-benefit effect of high efficient equipment in the demand-side bidding.

• Proceedings of the KIEE Conference
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• summer
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• pp.1397-1399
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• 2004

기존선 전철화, 철도시설물 정비사업 및 고속철도 연계 운행을 위한 우리나라의 전철화 구간용 궤도회로는 역 구내는 임펄스 궤도회로로, 역간은 AF 궤도회로로 선정하였다. 본 논문에서는 이들 궤도회로의 특성 및 역할을 열차운행속도와 안전측면에서 분석하였다.