• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.798-807
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• 2021

In the era of the fourth industrial revolution, Maritime Autonomous Surface Ship(MASS) are expected to emerge in the shipping industry. There has been much active research on collision avoidance systems regarding MASSs, but most of it has focused on merchant ships. A study of collision avoidance systems in fishing vessels is also essential, because Maritime Autonomous Surface Ships will encounter all type of vessels. In this study, the minimum passage distance between small-medium-sized fishing vessels and other vessels was investigated for the Ship's domain analysis. Based on the AIS data of Busan port and the adjacent area, the separation distances of fishing vessels were analyzed. The results indicated that as the speed of fishing vessels increased, the distance increased from 4L to 8L, and as length of the fishing vessels increased, the distance decreased from 10L to 6L. It is believed that the results of this study can be applied in the future to collision avoidance models for MASSs that reflect the domain of fishing vessels.

• Journal of Satellite, Information and Communications
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• v.6 no.1
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• pp.103-108
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• 2011

This paper is related radio interference from inductive system to radio device in home and industrial environment according to increasing the usage of inductive system. In order to analyze interference from magnetic field strength of inductive system, interference model was suggested and explain the method to calculate separation distance by using conversion that from magnetic field strength to magnetic dipole moment based on suggested interference model. Also, scenario that interference occur between inductive system and radio device was shown and the separation distance between inductive system and radio device was calculate with that scenario. The suggested method in this paper will be used to secure the compatibility between inductive system and radio device.

• The Journal of the Acoustical Society of Korea
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• v.14 no.3
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• pp.105-113
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• 1995

For the case of using analog FM system and CDMA system together in the mobile communications, we experimentally calculate the appropriate frequency offset to improve the frequency efficiency by analizing the interference between both systems. As the results of the analysis, we obtained that frequency offset is 840KHz(Path Loss : 80dB) and 720KHz(Path Loss : 120dB) for the Path Loss when a output of CDMA Base Station is 0.91 W ERP. Therefore, to minimize the frequency offset, a output of Base Station will be controlled corresponding to Cover Area.

• Tunnel and Underground Space
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• v.22 no.1
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• pp.60-68
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• 2012

Focusing on the load tunnel, this study assessed the behavior of rock pillars with less than 0.5D of the minimized distance between the two horizontal tunnels by using a three dimensional numerical analysis. Based on a parameter affecting the behavior of rock pillars, this study evaluated different safety factors according to pillar width, depth and rock conditions. It turned out that as the pillar width increases, the current curve of safety factors in accordance with depth and rock conditions shows more of the nonlinear behavior. Judging from the minimum safety factor, the study suggested a design chart, working on the minimized distance between the two horizontal tunnels.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.19-24
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• 2010

This paper analyzes potential interference effect of DTV service on Radio Microphone in adjacent channel. For analysis, we assume that DTV operates on CH 51(692 MHz ~ 698 MHz) and radio microphone operates on CH 52 (698 MHz ~ 704 MHz) according to the Korea Communications Commission policy. Minimum Coupling Loss(MCL) method is used to determine the required protection distance and Monte Carlo method is used to determine guard band to meet interference probability of 0 % below. In conclusions, protection distance of 1.71 km and guard band of 2.4 MHz are required for indoor and protection distance of 18.86 km and guard band of 5.7 MHz are required for outdoor.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.573-576
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• 2012

We have analyzed the induction effects by separation distance between the power feeding station and the telecommunication cables. To do this we measured the induced voltage in 11 sections(10km) between Jangseong and Imgok at Jeon-nam province using telecommunication cable installed nearby KTX's feeder line. Sub-section has about 1km length of telecommunication cable. And we used normalization method in installed length of telecommunication cables and mutual inductance to analysis the induction effects more rationally.

• Journal of Navigation and Port Research
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• v.29 no.10 s.106
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• pp.833-838
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• 2005

This paper is to investigate the minimum safe distance between T/S Hanbada and a group of vessels participating in the event hosted by M broadcasting station who asked T/S Hanbada to keep a distance from $100m{\sim}500m$. The minimum safe distance was assessed by using ES Model which evaluates quantitatively the difficulty of shiphandling, and the simulation of marine traffic flow. As a result the minimum safe distance of T/S Hanbada moving at a speed of 2 knots turns out about 260m and is compared with the actual value.

• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.225-231
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• 2019

In Korea, the minimum separation distance between aboveground high-pressure natural gas pipeline and buildings is regulated by Korea gas safety (KGS) code. In this paper, The technical backgrounds for the revision of the KGS code related to the minimum separation distance was presented. A consequence-based approach was adopted to determine the minimum separation distance by a reasonable accident scenario, which was a jet fire caused by the rupture of one inch branch line attached the gas pipeline. Where, the higher thermal radiation flux threshold was selected for workers in industrial area than for people in non-industrial area, because the workers in industrial area were able to escape in a shorter time than the people in public. As result of consequence analysis for the accident scenario, we suggested the KGS code revision that the minimum separation distances between high-pressure natural gas pipeline installed above ground and buildings should be 30 meter in non-industrial area and 15 meter in industrial area. The revised code was accepted by the committee of the KGS code and now in effect.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.152-155
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• 2011

최근 폭발 등 극한하중에 대한 관심의 증대와 함께 방폭 및 연쇄붕괴방지를 위한 연구가 활발히 진행되고 있다. 이에, 본 연구에서는 폭발하중하의 강구조물의 손상도와 저항성능을 수치적으로 평가하고자 하였다. 이를 위해 구조물의 폭발피해경감을 위해 가장 중요한 구조부재인 기둥을 대상으로 폭발물과 구조물과의 이격거리를 달리하여 폭발하중을 적용하였다. 유한요소해석을 수행한 결과를 토대로 기둥의 손상도와 잔여압축강도를 비교하고 관계를 도출하였다. 본 연구의 목적은 폭발에 의해 기둥이 손상된 경우 구조물 전체의 연쇄붕괴저항성능에의 손상된 기둥의 기여도를 평가하는 것이다.

• Fire Science and Engineering
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• v.18 no.2
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• pp.7-11
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• 2004

In this paper, we have simulated the force between the two electrical wires using the finite element method(FEM) according to the value of current and distance when overcurrent flows in the vinyl-insulated vinyl-cabtyre cord(flat-type, 600 V, VCTFK, $2C{\times}1.25mm^2$). And we will present the basic data for the identification of electrical fire by experiment for maximum distance between the two wires according to current and time using large current supply device(Model : EHT_EFAD, Korea) in case of overcurrent.