• Journal of the Korean Arthroscopy Society
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• v.15 no.2
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• pp.132-139
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• 2011

The concept of double-bundle ACL reconstruction was introduced recently to restore the anatomical and biomechanical functions of the native ACL. According to anatomical and biomechanical studies, the separate reconstruction of anteromedial and posterolateral bundle expect to increase the overall postoperative stability and clinical results compared to single-bundle ACL reconstruction. But there is still a lack of available clinical outcome studies with sufficient follow-up to demonstrate the real advantages of double-bundle ACL reconstruction. The purpose of this article is to review the evidence to support double-bundle technique and to address controversies existing over the usefulness of this technique.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.74-78
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• 2011

In this paper, the bandpass filter for ITS system of 5.8 GHz is proposed by using the dual-mode resonator with the radial stub. As alternating the open stub with the radial stub, the size of the dual mode resonator can be reduced about 39.6% and the out-of-band characteristics of the bandpass filter using dual mode resonator can be enhanced from 19.4 dB to 29.1 dB by using the stub of $6.9{\Omega}$ i.e. realized by parallel two radial stubs with $60^{\circ}$ angle. The fabricated bnadpass filter using the dual mode resonator has the center frequency of 5.72 GHz with the fractional bandwidth of 4.1%. Also, the filter has the insertion loss and return loss of 1.79 dB and 19.4 dB, respectively.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.5
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• pp.526-531
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• 2001

The flow of remote field eddy current energy is studied at nonmagnetic coaxial tubes by using both experiments and finite element calculations based on commercial software package. The results showed that remote field eddy current energy at coaxial tubes flow along over the outer surface of external tube, not through the gap between internal and external tubes. This means that the through wall transmission characteristic of remote field eddy current testing (RFECT) is still valid at tube in tube configurations and the RFECT could be potential nondestructive technique for crack detection, spacer location and gap sizing at the coaxial CANDU fuel channel tubes.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.3
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• pp.301-310
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• 2004

In this paper, a compact dual-mode filter structure without coupling gaps is proposed. The novel design is achieved by embedding a pair of equal crossed slots and spur-lines. Without coupling gaps between feed lines and patch resonator, the new filter can provide low insertion loss. It is found that this design has wide coupling range for dual-mode operation. It means that these characteristics of the proposed filter can reduce uncertainty in fabrication. By using two PIN diodes mounted inside a pair of spur-lines, the proposed structure works as a switchable filter. Also, it has a size reduction of about 34.7 %, compared with conventional dual-mode filters.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.508-512
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• 2007

In this paper, a novel wideband crossed planar monopole antenna with the double resonance characteristics is proposed. The proposed monopole antenna consists of a wideband crossed planar monopole antenna and L-shaped slits. In order to generate double resonance characteristics on the proposed monopole antenna, the length of L-shaped slit on the antenna surface is obtained from the quarter-wavelength of the second resonance frequency The double resonance characteristics of the proposed antenna can be easily designed by the control of length of L shaped slit at an interesting frequency. The proposed antenna having an omnidirectional radiation pattern and a high gain over the double resonance frequency bands, respectively, is suitable for mobile multiband antenna.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.209-209
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• 2013

그래핀(graphene)의 가장자리(edge)는 결정구조의 배향성에 따라 지그재그(zigzag)와 안락의자(armchair) 형태로 구분되는데, 나노미터 크기의 그래핀의 전자적 성질은 이러한 가장자리의 배향성에 의해 크게 영향을 받는다고 알려져 있다. 단일층 그래핀 가장자리 사이에서 일어나는 산화실리콘($SiO_2$)의 carbothermal reduction은 선택적으로 지그재그 형태의 가장자리를 생성한다고 알려져 있다. 본 연구에서는 라만 분광법과 원자 현미경(atomic force microscopy)을 이용하여 기계적 박리법으로 만들어진 이중층 그래핀에서 일어나는 carbothermal reaction을 연구하였다. 고온 산화 방법으로 이중층 그래핀에 원형 식각공(etch pit)을 만들고 Ar 기체 속에서 700도 열처리를 진행한 후, 원형 식각공이 육각형으로 확장된 것을 관찰하였다. 이것은 이중층 그래핀도 산화실리콘의 carbothermal reduction을 유발한다는 사실을 보여준다. 그러나 이중층 그래핀의 반응속도는 단일층보다 5배 정도 느린 것이 확인되었는데, 이는 이중층 그래핀의 탄소원자와 산화제로 작용하는 산화실리콘 간의 평균 거리가 단일층보다 더 크다는 사실로 설명할 수 있다. 또한 단일층과 이중층 그래핀 모두 1 기압 Ar 분위기에서보다 진공상태에서 반응속도가 현저히 작다는 사실이 관찰되었다. 진공도와 온도에 따른 반응속도로부터 반응 메커니즘 및 활성화 에너지에 대해 고찰하고자 한다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.7
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• pp.633-640
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• 2002

In this paper, the small chip meander antenna for dual-frequency operation is presented. The proposed chip meander antennas was fabricated by the ceramic chip using LTCC-MLC process. It is a novel compact dual-frequency design using a meandered patch that achieves more degrees of freedom for adjusting dual-frequency operation and the size reduction with narrow frequency ratio. And it is proposed that the 3D structure for additional size reduction of the meander antenna. The size reduction of the 3D meander antenna is as large as 50 % as compared to the design for dual-frequency operation not using 3D structure. It is observed that the principle of dual-frequency operation through current distribution, return loss and radiation pattern.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.753-758
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• 2011

According to the needs for equipment performance, reliability, and performance for impending time to guarantee its viability, various redundancy techniques have been used in many military systems. Typically, one of redundancy schemes to increase the viability of the system is to configure a network between two processes. However, when some failure or loss in a physical network occur, redundancy schemes may not operate well. In this paper, we present a protocol scheme of VMEbus master and slave of a shared memory region, interrupts, and a dedicated task communication. Specifically, we confirm the validity of the presented scheme through the direct implementation of the protocol and some experimental results.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.71-71
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• 1993

Diplophonia is produced by the voice of two separate tones and produced through quasi-periodic variations in the vocal cord vibration. Diplophonia is generally regarded as a symptom of laryngeal pathology. The difference in the vibratory frequency between the vocal cords can be seen in a tension imbalance and a difference in the level of the vocal folds under the special condition such as incomplete glottal closure. So authors have experienced 19 cases of patient with diplophonia for the unilateral vocal cord paralysis, intracordal cysts and other mass lesions. And we analysed the diplophonic voice with peak variability and noise level for the quasi-periodic waveforms and spectrograms pre-and postoperatively.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.277-284
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• 2017

This study is the results of the analytical research for a dual-model scramjet engine flowpath which is included inlet, isolator, combustor, and nozzle. To design a dual-mode scramjet engine and to investigate its performance, the performance analysis models and tools are required to develope for aerodynamic, thermodynamic characteristics, propulsion, and total system. Therefore, analysis models for air inlet, isolator, supersonic combustor, and nozzle of a dual-mode scramjet engine were accomplished, the performance characteristics of a dual-mode scramjet engine is investigated with using the developed analysis tools.