• Journal of Korea Multimedia Society
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• v.16 no.12
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• pp.1427-1438
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• 2013

We have developed a 128-bit stream cipher algorithm composed of the 5-stage pipeline, capable of real-time processing, confidentiality and integrity. The developed stream cipher is a stream cipher algorithm that makes the final 128-bit ciphers through a whitening process after making the ASR 277 bit and SHACAL-2 and applying them to the CFB mode. We have verified the hardware performance of the proposed stream cipher algorithm with Modelsim 6.5d and Quartus II 12.0, and the result shows that the hardware runs at 33.34Mhz(4.27Gbps) at worst case. According to the result, the new cipher algorithm has fully satisfied the speed requirement of wireless Internet and sensor networks, and DRM environment. Therefore, the proposed algorithm with satisfaction of both confidentiality and integrity provides a very useful ideas.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.12
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• pp.1233-1238
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• 2003

In this paper, radially corrugated circular-type microstrip patch antenna was devised and manufactured for GPS (center frequency: 1.575 GHz). Radially corrugated circular-type microstrip patch antenna having radiational corrugation-patch contributed to add size reduction ratio by lowering the resonant frequency because the edge current also has the extended and perpendicular path. As a result, radially corrugated circular-type microstrip patch antenna has 28 % area reduction than planer circular-type patch antenna for linear polarization and 27.7 % area reduction than planer circular-type patch antenna for circular polarization. Radially corrugated circular-type microstrip patch antenna is suitable for miniaturized receive antenna for GPS which has the characteristic of gain 2.1 dBd, axiai ratio 1.3 dB, 2 dB axial bandwidth 15 MHz(0.9 %).

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.516-516
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• 2012

약한 자기장 (~20 G)이 인가된 유도 결합 플라즈마 장치는 고효율, 높은 균일도의 플라즈마를 생성할 수 있다. 그러므로 이 장치에 대한 변수 제어뿐만 아니라, 전자 싸이클로트론 공명(Electron cyclotron resonance) 현상에 의한 방전 특성에 대한 연구는 매우 중요하다. 그에 연관된 여러 연구가 있었지만, 대부분의 연구는 평판형 유도 결합 플라즈마에서 진행되었다. 그에 따라서, 본 연구는 솔레노이드 형태의 유도 결합 플라즈마 장치에서 플라즈마 변수에 대한 약한 자기장의 영향을 살펴보았다. 실험에 사용된 인가주파수는 13.56 MHz에서 27.12 MHz였으며, 다양한 압력과 전력에서 실험이 진행되었다. 이러한 솔레노이드 형태의 유도 결합 플라즈마에서의 플라즈마 변수는 국부적인 특성을 보였으며, 평판형 유도 결합 플라즈마와 비교/분석을 진행하였다.

• IE interfaces
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• v.9 no.3
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• pp.22-33
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• 1996

The KOREASAT satellite, the first Korean commercial communication and broadcasting satellite, has been launched in August 1995, and has started to provide the communication and preliminary broadcasting services, respectively, in March and July 1996. In this paper the network configurations and characteristics of the services which the KOREASAT satellite provides are described. The services, which are provided by the KOREASAT satellite with its twelve communication and four broadcasting transponders, are the direct broadcasting service, the video relay service including the TVRO, SNG and TV/CATV program distribution, the company-wide communication service including VSAT and TSAT, and the other services with the digital line, trunk relay, telephone line, mobile data, music broadcasting services, etc. A communication transponder has the 36MHz bandwidth and 14W output power, and a broadcasting transponder has the 27MHz bandwidth and 12OW output power.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.74-74
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• 2009

The ArF PR mask was. developed to overcome the limit. of sub 40nm patterning technology with KrF PR. But ArF PR difficult to meet the required PR selectivity by thin PR thickness. So need to the multi-stack mask such as amorphous carbon layer (ACL). Generally capacitively coupled plasma (CCP) etcher difficult to make the high density plasma and inductively coupled plasma (ICP) type etcher is more suitable for multi stack mask etching. Hybrid Coupled Plasma source (HCPs) etcher using the 13.56MHz RF power for ICP source and 2MHz and 27.12MHz for bias power was adopted to improve the process capability and controllability of ion density and energy independently. In the study, the oxide trench which has the multi stack layer process was investigated with the HCPs etcher (iGeminus-600 model DMS Corporation). The results were analyzed by scanning electron microscope (SEM) and it was found that etching characteristic of oxide trench profile depend on the multi-stack mask.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.143.1-143.1
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• 2015

An inductively coupled plasma source driven by 13.56MHz was prepared for the deposition of a-C:H thin film. Properties of the plasma source are investigated by fluid simulation including Navier-Stokes equations and home-made tuned single Langmuir probe. Signal attenuation ratios of the Langmuir probe at first and second harmonic frequency were 13.56Mhz and 27.12Mhz respectively. Dependencies of plasma parameters on process parameters were agreed with simulation results. Ar/CH4 plasma simulation results shown that hydrocarbon radical densities have their lowest value at the vicinity of gas feeding line due to high flow velocity. For input power density of 0.07W/cm3, CH radical density qualitatively follows electron density distribution. On the other hand, central region of the chamber become deficient in CH3 radical due to high dissociation rate accompanied with high electron density. The result suggest that optimization of discharge power is important for controlling deposition film quality in high density plasma sources.

• Review of KIISC
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• v.4 no.1
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• pp.30-43
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• 1994

본 해설은 1993년 일본의 미쓰비스 전기(주)의 마쯔이가 세계 최초로 발표한 DES의 선형해독법을 1994년 1월 27일부터 1월 30일까지 개최된 SCIS'94에서 기 발표한 선형 해독법의 고속화 방법을 제안한 논문을 번역하여 소개한다. 이 방법으로 2$^{43}$ 개의 랜덤과 평문과 암호문이 주어진다면 DES의 모르는 키 56비트를 80%의 성공확률로 구할 수 있다. 또한, 이론을 실증하기 위해 50일간 12대의 W/S(PA-RISC, 99MHz, 125MIPA)을 이용하여 수행한 결과 EDS의 기지 평문 공격에 성공하였다고 한다.

• Korean Journal of Optics and Photonics
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• v.11 no.6
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• pp.423-428
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• 2000

We have demonstrated a -8 dB additional reduction in the intensity sidelobe of an apodized-interaction-strength guide-wave acousto-optic filter with a center passband of 1551.6 nm. Acoustic-intensity weighting was achieved by launching a surface acoustic wave (SAW) beam in a straight acoustic waveguide, and gradually transferring this SAW intensity to the active device, and back out, by evanescent-wave coupling across a 50 !lm barrier over a 19 rom interaction length. The intensity sidelobe was -4.27 dB for an unapodized filter with abmpt onset and cutoff of the interaction, but sidelobes were reduced to at most -12.68 dB for a SAW intensity with raised-cosine weighting. The RF driving power was 17.78 mW. A linear tuning rate of 8.86 nmIMHz and a spectral width of -1.7 nm were demonstrated. rated.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.1
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• pp.111-116
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• 2013

연구목적: 본 연구는 흰쥐를 대상으로 정강뼈의 관절연골에 적용한 맥동전자장과 맥동초음파가 HSP70(Heat shock protein 70)의 발현을 통한 연골 형성에 미치는 영향을 알아보고자 실시하였다. 연구방법: 36마리의 200~250g의 Sprague-Dawley 흰쥐를 대조군, 맥동전자장 적용군, 맥동초음파 적용군으로 각 집단별로 12마리씩 무작위 배정하여 실험을 진행하였다. 맥동전자장은 27.12 MHz의 주파수, 5가우스의 강도, 450 W의 출력으로 10분간 적용하였고, 맥동초음파는 20%의 맥동비, 1MHz의 주파수, $1.5W/cm^2$의 강도로 10분간 적용하였다. 연구결과: 맥동전자장 적용군과 맥동초음파 적용군의 관절연골 조직에서 유의한 수준의 HSP70 발현량을 나타냈다. 또한 맥동전자장 적용군과 맥동초음파 적용군에서는 Akt, Erk1, CREB의 높은 활성도를 나타내었고, 맥동초음파 적용군에 비해서 맥동전자장 적용군의 더 높은 수준의 활성도를 보였다. 결론: 맥동전자장과 맥동초음파는 HSP70의 과발현을 유발하고, 이를 통해 연골형성을 증가시키는 것으로 나타나, 향후 관절연골의 손상에 대한 임상적 적용을 위한 추가적인 연구가 진행되어야 할 것으로 생각된다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.12
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• pp.1139-1147
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• 2011

In this paper, a design and fabrication of GaN power amplifier for the S-band frequency (400 MHz bandwidth) are presented. A combining path using ${\lambda}$/4 transmission line is implemented for GaN pallet amp. Both the combiner with suspended-type transmission structure for low-loss and the suspended stripline coupler with aperture coupling for auto gain control are realized for achieving high-power high-efficiency amplifier. Proposed power amplifier demonstrated a 5 kW peak output power, 27.8 % efficiency, 67 dB gain without ALC and a 4 kW peak output power, 25.5 % efficiency, 0.1 dB droop at 200 usec pulse width and 10 % duty with ALC.