• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.2
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• pp.61-71
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• 2007

The instruction level parallelism, which has been used to improve the performance of processors, expose its limit. The change of a control flow by a branch miss prediction is one of the obstacles that restrict the instruction level parallelism. The single chip multiprocessors have been developed to utilize the thread level parallelism. However, we could not use the maximum performance of the single chip multiprocessor in case of executing the coded programs without considering the multi-thread. In order to overcome the two performance degradation factors, in this paper, we suggest the concurrent branch execution method that applies to the multi-path execution method at a single chip multiprocessor. We executes all two flows of the conditional branch using the idle core processor. Through this, we can improve the processor's efficiency with blocking the control flow termination by the branch instruction and reducing the idle time. We analyze the effects of concurrent branch execution proposed in this paper through the simulation. As a result of that, concurrent branch execution reduces about 20% of idle time and improves the maximum 10% of the branch prediction accuracy. We show that our scheme improves the overall performance of maximum 39% compared to the normal single chip multiprocessor and maximum 27% compared to the superscalar processor.

• Journal of the Korea Society for Simulation
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• v.15 no.4
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• pp.119-128
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• 2006

A turnout system which permits trains to pass from one track to another is a combination of the switch, the crossing, lead rails which are necessary to connect the switch and the crossing, two guard rails and a switch machine for operating the switch. A turnout is the sole moving part among the railway components and has complex configuration, so the safety has always been raised an issue. In Korea, it is planned to adopt the high speed tilting train, which operates at the maximum speed of 200km/h, at conventional lines by the year of 2010. However, for the application of the tilting train to conventional lines, it is prerequisite to establish a stable turnout system allowing the tilting train to pass through it without reducing speed. Therefore, the improved turnout system for the speed-up of conventional lines has been developed and the prototype of the turnout system has been constructed. In this study, simulation of noise and vibration around the improved turnout system was performed in order to predict the generation level of noise and vibration due to passing of the tilting train through the turnout system.

• Journal of the Korean Society for Railway
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• v.19 no.2
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• pp.135-144
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• 2016

It is essential to lighten the weight of switch girders in order to reduce their costs of manufacturing and make it easier to use them in construction. Lightening the weight of switch is also important to the Maglev 3-way switches system, however, the design variables should be considered very carefully if lightening is to be applied to the system, because these variables are vitally related to the levitation stability. Because Urban Maglev trains have a structure in which train bogie wraps around the guiderail, the adjustment of a girder's height is a possible way to reduce the weight. The safety of the application of this concept is ensured by repeated experiments in a test bed, however, due to a lack of space and budget limits, the design parametric study for the system model can substitute for actual application. The purpose of this paper is to study the design parameters that are concerned with levitation stability while a Maglev train is running on the Maglev 3-way system depending on the weight of the switch girders. In this study, switch girder weight is reduced by adjustment of girder height and girders are and modeled as a flexible body. The effect of the adjustment of girder height on the levitation stability can be analyzed by comparing the velocity of the train when it passes the switch girders, with the lateral gap, and the levitation gap which are obtained from the co-simulation of the Maglev train's dynamics model and flexible switching system. The results of this research will be used to design a Maglev switch.

• KAPE Magazine
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• no.9 s.145
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• pp.6-7
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• 2008

한국농촌경제연구원은 지난 8월 25일 2008년 4/4분기 축산관측을 발표했다. 발표에 따르면 한육우는 산지가격 증가, 젖소는 사육두수 감소, 돼지의 산지가격은 25-27만원으로 전망했다. 또한 산란계의 사육수수는 증가, 육계의 사육수수는 감소할 것으로 전망했다. 이에 본지는 축종별 전망을 요약해 게재한다.

• LP가스
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• s.70
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• pp.50-51
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• 2000

LPG충전소의 안전관리상태가 양호한 것으로 나타났다. 가스안전공사에 따르면 지난 상반기동안 2백61곳의 LPG충전소를 대상으로 가스안전관리 종합평가를 실시한 결과 96.6%에 해당하는 2백52곳이 법정 최소기준인 60점이상의 점수를 받은 것으로 조사됐다. 2/4분기 LPG충전소 안전관리종합평가를 게재한다.

• KAPE Magazine
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• s.136
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• pp.6-7
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• 2007

한국농촌경제연구원이 지난 11월 25일 발표한 2008년 1/4분기 측산관측에 따르면 한육우는 전반적 하락, 젖소 사육두수 감소세 지속, 돼지는 21~22만원으로 전망했다. 산란계는 감소, 육계는 사육수수가 증가할 것으로 전망했다. 이에 본지는 축종별 전망요약을 게재한다.

• 정보화사회
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• s.180
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• pp.42-44
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• 2006

국내 빅3에 의한 1분기 휴대폰 출하 실적이 5000만대에 달했다. 산술적인 계산으로도 연간 2억대 돌파 시대가 다가왔음을 알 수 있다. 작년 빅3에 의한 연간 실적이 1억7000만대 수준이었던 것과 비교한다면 엄청난 증가를 예상할 수 있다. 국내 업체들의 실적향상도 있었지만 그만큼 세계 휴대폰 시장이 커졌기 때문이다.

• Magazine of korean Tunnelling and Underground Space Association
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• v.14 no.6
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• pp.12-18
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• 2012

• IT SoC Magazine
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• s.13
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• pp.24-28
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• 2006

우리나라 Fabless업체들의 1사분기 실적은 올 한 해 전망을 낙관적으로 봐도 될 만한 모습을 보여 주었다. 2006년도 1사분기 평균매출액은 작년 동분기보다 29% 증가한 82억7천만원을 기록했으며, 전체 조사대상 업체의 70%가 전년 동분기보다 매출이 증가한 것으로 나타났다.

• KAPE Magazine
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• s.127
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• pp.6-7
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• 2007

한국농촌경제연구원이 자난 2월 25일 발표한 2007년 2/4분기 축산관측에 따르면 한육우의 경우 가격하락, 젖소사육두수 감소, 돼지는 24~25만원으로 전망했다. 산란계, 유계는 사육수수가 증가할 것으로 전망했다. 이에 본지는 축종별 전망 요약을 게재한다.