• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2012년도 춘계학술논문집 2부
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• pp.817-819
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• 2012

This paper propose an interested digital rights protection scheme to address problems facing contemporary DRM approached : static digital rights management, and limited application to on-line environment. We introduce a dynamic mission control technology to realize dynamic digital rights management. And we incorporate license agent to on- and off-line monitoring and tracking. The proposed system prevent illegal access and use by using PKI security method, real time action monitoring for user, data security for itself.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 춘계종합학술대회
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• pp.330-334
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• 1999

This paper presents a new transient voltage blocking device (TBD) for commucation facilities with low power and high frequency bandwidth. Conventional protection devices have some problems such as low frequency bandwidth, low energy capacity and high remnant voltage. In order to improve these limitations, the new TBD, which consists of a gas tube, avalanche diodes and junction type field effect transistors (JFETs), was designed and fabricated JFETs were used as an active non-linear element and a high speed switching diode with low capacitance limits high current. Therefore the avalanche diodes with low energy capacity are protected from the high current, and the TBD has a very small input capacitance. From the performance test using surge generator, which can produce 1.2/50${\mu}\textrm{s}$ 4.2 k$V_{max}$, 8/20${\mu}\textrm{s}$ 2.1 kA$\sub$max/, it is confirmed that the proposed TBD has an excellent protection performance in tight clamping voltage and limiting current characteristics.

• Journal of Radiation Protection and Research
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• 제45권1호
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• pp.11-15
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• 2020

Background: There have been various studies to investigate the mechanisms of DNA damage from low-energy electrons. To understand the mechanism of these strand breaks, it is necessary to investigate the dissociation mechanism of the DNA constituents, that is, bases, sugars, and phosphates. Materials and Methods: We studied the dissociation of thymine base upon interaction with low-energy electrons. For this experiment, thymine powder was pressed onto the indium base and irradiated by 5 eV electrons. Results and Discussion: Non-irradiated and irradiated thymine samples were compared and analyzed using the X-ray photoelectron spectroscopic technique to analyze the dissociation patterns of the molecular bonds after low-energy electron irradiation of thymine. Conclusion: With 5 eV electron irradiation, C-C and N-C = O bonds are the primary dissociations that occur in thymine molecules.

• 전자공학회논문지 IE
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• 제47권4호
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• pp.28-33
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• 2010

본 연구에서는 Fuse의 캡 tinning 후 불량선별 공정을 자동화하기 위한 알고리즘을 설계하였다. 퓨즈 제조공정에서 퓨즈의 캡에 납을 삽입하는 것을 tinning 공정이라 한다. Tinning 후 불량선별을 하는 공정에서 기존에는 사랑의 육안에 의해 검사 하였으나, 본 연구에서는 CCD 카메라를 이용하여 불량을 검사 하는 알고리즘을 설계 하였다. 검사 알고리즘은 캡의 내부를 촬영한 후 촬영된 이미지를 영상처리 과정을 거쳐서, 캡 내부의 납의 분포도를 검사하고 기준값과 비교하여 불량을 선별하도록 하였다.

• Smart Structures and Systems
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• 제4권2호
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• pp.261-278
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• 2008

The results of the application of shape memory alloy (SMA) prestressing devices on an aqueduct are presented in this paper. The aqueduct was built in 1747 to provide water to the city of Larnaca and to its port. Because of its importance to the cultural heritage of Cyprus, the aqueduct has been selected as one of the case-study monuments in the project Wide-Range Non-Intrusive devices toward Conservation of Historical Monuments in the Mediterranean Area (WIND-CHIME). The Department of Antiquities of Cyprus, acting in a pioneering way, have given their permission to apply the devices in order to investigate their effectiveness in providing protection to the monument against probable catastrophic effects of earthquake excitation. The dynamic characteristics of the structure were determined in two separate occasions and computational models were developed that matched very closely the dynamic characteristics of the structure. In this paper the experimental setup and the measured changes in the dynamic characteristics of the monument after the application of the SMA devices are described.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.507-513
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• 2010

This paper is described the analysis of time-varying low-frequency electric magnetic field emitted from electric rolling stocks fed by VVVF inverter, in reference to allowable magnitude for exposures to time-varying electromagnetic field issued by International Commission on Non-Ionizing Radiation Protection(ICNIRP). The level of the magnetic field strength was measured, in reference to the standard for occupational environments, which takes into account the public person's protection against the excessive emission of the low-frequency magnetic field, 5 Hz ~ 2 kHz.

• Journal of Radiation Protection and Research
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• 제25권2호
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• pp.109-114
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• 2000

The SI unit of specific absorption rate (SAR) in W/kg in the electromagnetic (EM) field as non-ionizing radiation is exactly same as the SI unit of absorbed dose rate in Gy/s in the ionizing radiation field. The SI unit of both physical quantities can be expressed in $[m^{\cdot}s^{-3}]$. Where, the unit of absorbed dose, Gy stands for Gray. In EM biological interactions, the SAR equations are derived and the characteristics of EM field energy absorption in terms of the SAR are discussed and described on the mathematical basis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1688-1690
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• 2002

The unpredictable threat of lightning surge is ever increasing in today's low-voltage power supplies. Thus Surge protection devices for AC mains are more widely used. The false-tripping of the earth leakage breaker (ELB) can be caused by the installation of surge protection devices with MOV. In order to examine the cause of malfunction, the malfunction characteristics of ELBs applied by lightning surge were investigated experimentally. As a result, all of them brought about malfunctions under 7 kV of the impulse voltage. The suitable position of MOV and use of zener diode were suggested to eliminate the problems.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권1호
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• pp.128-134
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• 2012

This paper gives an overview of the requirements for electrical equipment in potentially explosive atmospheres and describes how these are applied to electrical machines and drives in hazardous areas. The method by which equipment can be shown to be safe in a whole range of gases, by testing in a single test gas, is covered. It is shown how the more recently introduced methods of protection for hazardous areas, increased safety and nonsparking, are ideally suited to AC machines and drives. A novel method of measuring the fullload temperature rise of electrical machines for hazardous, and other areas, without the need to connect a mechanical load to the machine's drive shaft is explained.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4267-4270
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• 2012