• ETRI Journal
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• v.32 no.4
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• pp.603-606
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• 2010

In this letter, we propose a channel estimation algorithm based on incremental pilots. These are pilots additionally inserted after puncturing the modulated orthogonal frequency division multiplexing (OFDM) symbols to enhance channel estimation performance without lowering bandwidth efficiency. A low-density parity-check code puncturing scheme is also proposed to prevent the performance degradation due to the codeword bit loss caused by punctured OFDM symbols.

• Annual Conference of KIPS
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• 2010.04a
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• pp.717-720
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• 2010

This paper considers the Quality of Service (QoS) provisioning mechanisms for the WDM burst switched ring networks. The loss-sensitive service and the delay-sensitive service are discussed. Considering their different requirements, different QoS provisioning schemes are proposed to provision them respectively. The proposed schemes are evaluated through simulation results.

• Journal of Navigation and Port Research
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• v.35 no.4
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• pp.299-302
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• 2011

In this letter, the effect of quality factor on center frequency deviation in miniaturized coupled line bandpass filter (BPF) with diagonally end-shorted at their opposite sides and lumped capacitors is theoretically analyzed. The miniaturized BPF of a two-stage structure with two types of quality factors in standard CMOS process was designed and manufactured at 5.5 GHz. The die area of BPF was $1.44{\times}0.41\;mm^2$. The measured center frequency of BPF with a quality factor of 4.9 was deviated from 5.5 GHz to 4.7 GHz. The one with 14.8 was shifted to 5GHz. The theoretical and measured results validate that quality factor influences the center frequency shift of BPF.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.60-60
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• 2004

• Journal of Navigation and Port Research
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• v.36 no.9
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• pp.737-740
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• 2012

A miniaturized CMOS bandpass filter for a single RF transceiver system is presented, using diagonally end-shorted coupled lines and lumped capacitors. In contrast to conventional miniaturized coupled line filters, it is proven that the effective permittivity variation of the coupled transmission line has no effect on shifting the center frequency when the bandpass filter is highly miniaturized. A bandpass filter at a center frequency of 2 GHz was fabricated by $0.18{\mu}m$ CMOS technology. The insertion loss with the die area of $1500{\mu}m{\times}1000{\mu}m$ is -5.14 dB. Simulated results are well agreed with the easurements. It also verify the center frequency stability in the compact size bandpass filter.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.367-371
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• 2010

본 논문에서는 1200V, 50A급의 컨버터 인버터 일체형 12-스위치 저 손실 지능형 전력모듈을 소개한다. 게이트 구동회로, 보호회로, IGBT 모듈을 통합한 이 전력모듈은 최적의 게이트 구동회로, 시스템 고밀도화 그리고 인피니언의 트렌치 필드스톱2 IGBT와 FRD를 사용한 높은 효율의 컨버터와 인버터 일체형으로 구현하였다. 본 논문을 통해 높은 파워가 요구되는 가전기기, 산업용 인버터의 애플리케이션에 적합하게 설계된 전력모듈에 대한 소개와 함께 그 특징 및 시스템 구성을 위한 고려사항에 대하여 기술하였다.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.282-287
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• 2013

The concentrated winding configurations offer significant advantage for reducing end windings. These machines are generally used in low speed high torque application due to relatively low copper loss. However, numbers of fractional slot construction make the designer hard to properly choose pole and slot numbers for the certain application. This paper provides the general information of possible fractional slot concentrated double layer winding machine.

• Annals of Clinical Neurophysiology
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• v.17 no.2
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• pp.80-81
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• 2015

Syncopes are the most common non-epileptic attacks mimicking epileptic seizures. Among them, cardiogenic syncope is potentially life threatening. A 49 year old man was refered for the recurrent episodes of loss of consciousness with tonic posture and upward eyes deviation. The electrocardiogram showed polymorphologic ventricular tachycardia during attacks, which normalized after that. He was treated with isoproterenol and symptoms subsided. Here, we report a case of ventricular tachycardia manifested as epileptic seizures.

• Journal of the Korean Chemical Society
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• v.67 no.2
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• pp.129-136
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• 2023

Osteoarthritis is to the abnormality of the inflammatory response of joint tissue caused by various causes such as aging, and muscle loss. In this study, the activity in joint inflammation was verified using SKBE, a plant extract, and the expression levels of arthritis-inducing proteins including MMP-1, MMP-3, MMP-13, and collagen type II in vitro were compared and analyzed. Furthermore, we synthesized α-spinasterol, an active ingredient of SKBE, by the previously reported synthesis method and these findings could provide a new starting point for the development of treatments for osteoarthritis.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.3
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• pp.306-310
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• 2023

Traumatic internal carotid artery injuries can produce direct carotid-cavernous fistulas as well as giant internal carotid artery pseudoaneurysms. Clinical sequelae can include headaches, cranial nerves palsies, proptosis, chemosis and optic neuropathy with visual loss as the most dangerous complication. Herein, we present a case of one of the largest reported internal carotid artery pseudoaneurysms associated with a direct carotid cavernous fistula. We describe the techniques and pitfalls of treatment with parent vessel occlusion.