• 융합보안논문지
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• 제17권2호
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• pp.159-164
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• 2017

국제사회는 북한의 핵 미사일 도발을 실질적인 위협으로 인식하고 있다. 이러한 배경에는 북한의 핵 미사일에 의한 직접적인 공격도 우려되지만, 북한이 핵전자기파(NEMP)탄을 개발했다는 전자기파(EMP)관련 전문가들과 국내외 정보기관들의 분석과 평가가 있기 때문이다. 전자기파 전문가들은 다음과 같은 측면에서 북한의 핵전자기파탄을 우려하고 있다. 우선, 현대사회의 산업 군사 의료 생활시설 등은 전기 전자시스템으로 구축되어 있어, 북한의 핵전자기파탄이 고도에서 폭발한다면 모든 전기 전자기기는 무력화된다. 다음으로, 공격자의 입장에서 핵전자기파탄은 상대국의 전기 전자기기 시설만을 파괴하고, 인명을 살상하지 않기 때문에 국제사회의 비난가능성이 낮다는 판단을 할 수 있다. 마지막으로, 핵전자기파탄은 목표물을 정확하게 타격할 필요가 없고, 저급한 핵무기의 수준으로 광범위한 지역을 타격할 수 있기 때문에 대량살상무기(WMD)보다 더 위협적이라 할 수 있다. 이러한 측면에서 북한의 핵 미사일 개발에 대한 분석과 평가를 통하여, 북한의 핵전자기파탄 개발에 대한 전망을 하고자 한다.

• 한국자동차공학회논문집
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• 제14권5호
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• pp.107-114
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• 2006

This paper investigates the radiating source of electro-magnetic waves in the cabin of automobile with spark ignition engine. Front seats are very close to the engine room where electro-magnetic waves are expected to be radiating. But front seat area is believed to be a blind zone, which is not affected by radiating electro-magnetic waves, because a bulk board and floor board shield the front seat area. The level and frequency spectrum of electro-magnetic waves are measured at the passenger seat and the engine room. The measured frequency range is $145{\sim}365MHz$. As a results, the level of the electro-magnetic waves of automatic transmission vehicle is greater than -82dBm. The shapes of frequency spectrum of both engine room and passenger seat are look alike. But the level of electro-magnetic waves of manual transmission vehicle is less than -82dBm and the shapes of frequency spectrum of engine room and passenger seat are different to each other. From these results, we can say that any mal-function caused by electro-magnetic waves in the automobile cabin are only possible for automatic transmission vehicle. Also, it is believed that the radiating source of electro-magnetic waves is inside the vehicle. Thus, based on the transmission line theory, this paper presumably concludes that the cables which connect all the components inside a automatic transmission vehicle must be a radiating source of electro-magnetic waves in the cabin.

• 수산해양기술연구
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• 제30권3호
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• pp.182-188
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• 1994

In recent years, navigational and fisheries instruments are rapidly advancing. Especially data processing. data transferring and data interchange throughout the digital signals has been in high progress. Even though the ship's heading is also provided by a gyro-compass, an electro-magnetic compass studying by us currently is easy to issue adequate data to instruments requiring the information for the ship's heading. especially in small fishing boats. As the main element of the electro-magnetic compass is a three-axis magnetic sensors, the developing of the high performance sensor is in highly necessity in the beginning. This paper describes on the development of electro-magnetic compass of three-axis fixed type by using three-axis detection new type magnetic sensor without gimbals. even though usual electro-magnetic compass have to need necessarily a gimbal system in order to keep horizontal condition of the compass.

• 대한기계학회논문집A
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• 제25권3호
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• pp.362-368
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• 2001

To design a limiting MCCB (Molded Case Circuit Breaker) mechanism, a dynamic modeling of the mechanism in which the electro-magnetic force effects are incorporated needs to be developed. Conventionally, electro-magnetic effects were considered separately for the design of the mechanism. In this paper, an electro-magnetic force that is induced by limited current is identified and included in the dynamic modeling of the mechanism. Thus, the electro-magnetic which is defined as a external force and the mechanical effects are simultaneously considered for the design of the mechanism which is composed of contactor, spring , link, latch and so on.

• 한국자동차공학회논문집
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• 제12권1호
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• pp.209-215
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• 2004

This paper presents the frequency range and an analysis method to find the dominant source of electro-magnetic wave which originates from a spark ignition in engine room. Applying the distributed constant equivalent circuit theory the radiation of probable electro-magnetic wave around an ignition plug and a high voltage cable is studied analytically. Experimental studies are also conducted by measuring the frequency spectrum to obtain the radiating characteristics of electro-magnetic wave. Results from both analytical and experimental studies confirm that an ignition plug and a high voltage cable are dominant sources of electro-magnetic wave and that the radiating frequency is ranged from 1.3[GHz] to 2[GHz] band.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1996년도 춘계학술발표회 초록집
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• pp.73-87
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• 1996

The outer-most electrons of metal atoms and the remining valence electrons of any molecular atoms make three dimensional crystallizing $\pi$-bondings. The electrons on the $\pi$-bonding orbital rotate clockwise or counter-clockwise and they then make electro-magnetic waves between atoms on the orbital because electron move between plus charged ions. The three dimensional crystallizing $\pi$-bonding orbitals are quantum-mechanically modeled by a cyclic Kronig-Penny Model and energy band structures are analyzed with their potential barrier thickness. The waves generated between plus charged ions are the particular $\pi$-far infrared rays, which have dual properties between material and electro-magnetic waves and can be measured not by modern electro-magnetic tester but biosensor such as finger's force tester. Because the $\pi$-rays can be modulated with electro-magnetic waves it can be applied for harmful electro-magnetic wave killers. Because the $\pi$-rays make new three dimensional crystallizing $\pi$-bonding orbitals in the material the food and drink can be transformed into a helpful physical constitutional property for human health. Distinction between crystalline and amorphous metals is possible because very strong crystalline $\pi$-bonding orbitals can not easily be transformed into another. The $\pi$-rays can also be applied for biofunctional diagnostics and therapy. Gravitational field is one of the electro-magnetic fields. And also magnetic field and gravitational force field make charge's movement. ($\times$ = q, : magnetic field, : force field, q: plus charge, : velocity field)

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.515-518
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• 2002

In this study, the ellipsoidal cap type magnetic pole structure was proposed for the electro-magnet in B-H curve tracer. From the simulation for the electro-magnet without specimen, the area of effective uniform field(99% range for the central field value) was considerably increased in case of the newly proposed ellipsoidal cap type magnetic pole than that of the conventional simple-inclined cap type magnetic pole. Also, through the simulation for the electro-magnet with permanent magnet specimen(NaFe30), the optimal Positions of the magnetic field measurement sensor(Hall sensor) were found out in each case and the errors were decreased in case of the newly proposed ellipsoidal cap type magnetic pole.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 춘계 학술대회논문집
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• pp.166-171
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• 2004

Direct numerical simulations are peformed to investigate the physics of a spatially developing turbulent boundary layer flow suddenly subjected to spanwise oscillating electro-magnetic forces in the near-wall region. The Reynolds number based on the inlet momentum thickness and free-stream velocity is $Re_\theta=300$. A fully-implicit fractional step method is employed to simulate the flow. The mean flow properties and the Reynolds stresses are obtained to analyze the near-wall turbulent structure. It is found that skin-friction and turbulent kinetic energy can be reduced by the electro-magnetic forces. Instantaneous flow visualization techniques are used to observe the response of streamwise vortices to spanwise oscillating forces. The near-wall vortical structures are clearly affected by spanwise oscillating electro-magnetic forces.

• 한국기계가공학회지
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• 제13권1호
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• pp.66-71
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• 2014

In this research, a material test machine is developed which uses a small electro-magnetic actuator and a leverage mechanism. The leverage mechanism amplifies the force from the electro-magnetic actuator. The electro-magnetic part operates more silently and cleanly than a hydraulic part. In a tooth material study, a test machine does not require a large force capacity because it handles only $4mm^2$-sectioned and short-span specimens. Conventional test machines such as those by Instron and the BOSE Enduratec ELF3200 have too high aforce capacity for a tooth material study. A test machine for a tooth material study requires an acting force only on the order of tens of Newtons (N) operating at several Hertz.

• 동력기계공학회지
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• 제3권1호
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• pp.60-66
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• 1999

Most of the small-type fishing boats in this country don't have the autopilot system such as the large ships have. In this papers, we describes on the development of electro magnetic compass for the autopilot system of the small-type fishing boat, which is utilized the MR(magnetic resistance) device and the inclination sensor. And we investigated the validity of the developed electro magnetic compass through results of actual experiment.