• 한국항해항만학회지
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• 제26권5호
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• pp.555-561
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• 2002

연안 경비함정의 선상근무 환경은 육상근무 환경에 비하여 매우 열악하여 선상근무 기피와 선원 고령화의 원인이 되고 있다. 특히 선박내 공기오염과 전자파는 직업병을 유발시키는 원인이 된다. 따라서 안락한 선상근무 환경 및 거주 환경의 확보를 통하여 선상근무 피로도를 경감시키는 것이 필요하다. 본 연구에서는 먼저 선박내의 공기오염과 전자파의 실선 계측을 통하여 선상근무 환경을 체계적으로 평가한다. 그리고 선상근무 환경의 평가 결과에 기초하여 선상근무 피로도 경감대책을 제안한다.

• Journal of electromagnetic engineering and science
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• 제11권4호
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• pp.269-273
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• 2011

A medical environment in which patient information can be accessed anytime / anywhere is called a "ubiquitous environment". To realize such an environment, the installation of wireless LAN is quite effective. Because the maximum radio wave output (antenna power) is set low in Japan, it has been easy to safely introduce wireless LAN into hospitals, to date mainly into large hospitals. However, if the placement of access points is not done properly, problems will occur, such as signals not reaching the desired area. A solution to these types of problems is to do an electromagnetic-field propagation simulation, which should be performed before construction of the hospital. It is also necessary to protect against security problems, such as signal interception or illegal access. We herein show our procedures for the safe introduction of wireless LAN.

• 한국전자파학회논문지
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• 제27권11호
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• pp.1023-1026
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• 2016

우주 환경에서의 굴절률 변화를 고려하여 안테나의 전파 특성을 계산한다. 대류권, 성층권, 전리권의 유효 굴절률을 계산하고, 대기권을 통과하면서 굴절되고 감쇠되는 전파 특성을 계산하기 위해 광선 추적법, 기하광학법, 호이겐스의 원리를 이용한다.

• 한국군사과학기술학회지
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• 제5권2호
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• pp.116-122
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• 2002

Electro Explosive Devices can be susceptible to electromagnetic interference. When these components are exposed to external electromagnetic fields, it may cause to induce sufficient current to generate enough heat for an inadvertent detonation. It is almost impossible to monitor the event of firing throughout the electromagnetic environment test. The survivability of EED for hazards of electromagnetic radiation is investigated. A fiber optic sensor is installed near the bridge wire after removing explosive material in order to measure the induced current on the bridge wire. The length of lead-wire of the EED fabricated is around 15 cm.

• Journal of information and communication convergence engineering
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• 제13권1호
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• pp.36-41
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• 2015

With the rapidly increasing and widespread use of electronic and controlling equipment, the control of the electromagnetic (EM) wave environment becomes an important social issue. To solve the electromagnetic compatibility (EMC, both electromagnetic interface and electromagnetic susceptibility) problems, in this paper, we introduce the countermeasure techniques focused on EM wave absorbers for EMC problems in our laboratory at the Korea Maritime and Ocean University. The current technologies related to EM wave absorbers to solve EMC problems will first be described. The prospects of and a design for EM wave absorbers including a smart absorber with a heat radiating function will then be suggested.

• 한국전자파학회논문지
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• 제12권7호
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• pp.1115-1121
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• 2001

본 논문에서는 실내 무선 통신 환경에서 발생하는 페이딩 현상과 전자기기에서 방출되는 임펄스성 전자간섭 파에 따른 GFSK 시스템의 성능을 분석하고 데이터 전송 서비스를 만족하기 위하여 성능 보상 방안으로 Truncated Type-II Hybrid ARQ 기법을 적용하여 열화된 시스템의 성능을 개선하였다. 결과에 의하면, 페이딩과 임펄스성 전자간섭파에 의해 시스템에 심각한 영향을 미치게 되는데 특히, 직접파 성분이 존재하는 페이딩 보다는 임펄스성 전자간섭파의 발생빈도와 크기에 따라 시스템 성능이 크게 좌우됨을 알 수 있었다. 성능 개선책으로 Truncated Type-II Hybrid ARQ 기법을 채용함으로써 낮은 신호전력(20 dB)에서도 향상된 성능 개선을 얻을 수 있었고, error floor 구간이 형성되고 시스템에 영향을 크게 미치는 강한 임펄스성 전자간섭파 환경에서도 24 dB 이상에서 성능 개선을 얻을 수 있었다.

• Journal of Magnetics
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• 제20권1호
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• pp.86-90
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• 2015

Electromagnetic actuators are versatile and able to meet demanding requirements, such as operation in very low or very high temperatures. When the actuator is used in a high-temperature environment up to $500^{\circ}C$, we need to know how the force-producing capability of the actuator is affected by the operating temperature. Specifically, it is necessary to know the temperature-dependence of magnetic properties that determine the mechanical forces. In this paper, we measure the changes in magnetic properties of SUS410 material in high-temperature environment. We also devise a novel signal processing technique to remove the integration drift. At the field strength of 18,000 A/m, we found that the flux density at $500^{\circ}C$ is decreased by 26%, compared to the result at room temperature. Therefore, the actuator must be sized appropriately, if it is to operate in high-temperature settings.

• ETRI Journal
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• 제40권4호
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• pp.546-553
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• 2018

Since the Gyeongju earthquakes in 2016, there have been increased research interests in the areas of seismic design, building collapse, and rescue radar applications in Korea. Ground penetrating radar (GPR) is a nondestructive electromagnetic method that is used for underground surveys. To properly design ground penetrating radar that detects buried victims precisely, it is important to study electromagnetic wave propagation channel characteristics in advance. This work presents an electromagnetic propagation environment analysis of a trapped victim for GPR applications. In this study, we develop a realistic collapse model composed of layered reinforced concrete and a victim positioned horizontally. In addition, the effects of rebars and the distance between the radar antenna and target are investigated. The numerical analysis presents the electromagnetic wave propagation characteristics, including amplitude loss and phase difference, in the 450-MHz and 1,500-MHz frequency band, and it shows the electric field distribution in the environment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.2031-2033
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• 2004

In this paper, electromagnetic wave environment generated from electronic equipments was investigated. Since the main source of electromagnetic waves are electronic equipments, the field intensity of a harmful electromagnetic wave was measured and its harmful level was analyzed. It was also found that the result was 23%${\sim}$38% in case of TV set and microwave oven. Based on this analysis, this study proposed efficient shielding method to suppress unwanted electromagnetic wave.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.21-22
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• 2008

Recently, we are living in environment which various electrical appliance help our life. But the meanwhile, we had not researched how far the electromagnetic waves of electrical appliance affected the human's life. In accordance with, this paper will find out how far the human are weighed with electromagnetic waves of electrical appliance. And we will demonstrate the method that humans are failed under minimum effect from the harmful electromagnetic waves.