• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.79-85
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• 1997

Fast spin echo imaging utilizes multiple spin echoes to encode multiple k-space lines instead of multiple $T_2-weighted$ images. As results, intensities in k-space data are varying according to T2 decay, which generates Gibb's artifact in the reconstructed image. The echo time for e encoding dc block determines contrast, as is specified by the effective echo time, however, all location of other echoes to different k-space frequency blocks in fast spin echo imaging is not f fully investigated. In this study, symmetric arrangement of multiple echoes in k-space is investigated to reduce Gibb's artifact. Design of filters based on the measurement of multiple e echo intensities is also proposed in two stage manner, i.e., equalization and filtering. From s simulation and experiment, it was observed that Gibb's phenomena were substantially reduced b by the proposed methods.

• Investigative Magnetic Resonance Imaging
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• v.20 no.3
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• pp.141-151
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• 2016

Purpose: Advances of magnetic resonance imaging (MRI), especially that of the Ultra-High Field (UHF) MRI will be reviewed. Materials and Methods: Diffusion MRI data was obtained from a healthy adult young male of age 30 using a 7.0T research MRI scanner (Magnetom, Siemens) with 40 mT/m maximum gradient field. The specific imaging parameters used for the data acquisition were a single shot DW echo planar imaging. Results: Three areas of the imaging experiments are focused on for the study, namely the anatomy, angiography, and tractography. Conclusion: It is envisioned that, in near future, there will be more 7.0T MRIs for brain research and explosive clinical application research will also be developed, for example in the area of connectomics in neuroscience and clinical neurology and neurosurgery.

• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.47-51
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• 2015

Sarcomatous Intrahepatic cholangiocarcinoma is a rare but an aggressive variant of cholangiocarcinoma with a very poor prognosis. A 79-year-old man was admitted to our hospital because of incidentally found liver mass. Magnetic resonance imaging (MRI) revealed well-defined hypointense mass on T1WI and heterogeneous hyperintense mass on T2WI. Gd-EOB-DTPA enhanced study shows peripheral rim-like enhancement in arterial phase and progressive concentric filling of contrast in delayed phase. And mass shows significant enhancement in hepatobiliary phase. The pathologic diagnosis was intrahepatic cholangiocarcinoma with sarcomatous change.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1249-1253
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• 2007

제방은 제내지에 거주하는 인간의 재산과 삶을 방어하고, 홍수를 제어하는 가장 기본적인 수공구조물이다. 제방파괴 원인은 월류, 활동, 침식, 그리고 침투 등으로 분류되어 질 수 있다. 특히 간극수압에 의해 발생하는 침투는 제방 내부침식(internal erosion) 및 파이핑(piping) 등을 야기함으로서 제방파괴를 유도한다. 침투에 의한 제방파괴는 월류나 침식에 의한 제방파괴 유형보다 상대적으로 적으나, 다른 제방파괴 원인을 더욱 활성화 시키는 인자로 작용한다. 도시하천의 경우 높은 치수안전도를 적용하여 제방을 축조함에 따라 월류에 의한 붕괴보다 강우와 하천수의 복합요인에 의한 침투파괴가 중요한 문제로 대두되고 있다. 본 연구에서는 침투와 활동에 대한 안전성을 확보할 수 있는 침투보강기법인 단면확대기법에 대한 적용성 및 유의사항을 수치모의를 통해 검토하였다. 제방 비탈면 경사를 1:2 확대할 경우, 침투유속이 70 %정도 감소되는 것을 확인하였다. 그러나 단면확대기법은 홍수시 통수능과 제내지의 부지 확보 문제 등을 고려하여 적용하여야 하며, 도시하천에서 단면확대기법을 적용하는 데는 일정부분 한계를 가질 것으로 판단된다.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.2
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• pp.102-111
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• 1995

The non-periodic fluctuation of the engine torque appears to be the major source of the torsional vibration of the automotive driveline. The reduction of this torsional vibration has become a significant problem along with the requirements of higher performance. The torsional vibration of the automotive driveline can be reduced by smoothing the fluctuation by adjusting the torsional characteristics of the clutch-disc. Computer simulation of the driveline is a useful investigative tool on studying the torsional characteristics of the clutch-disc. In this paper, a dynamic model for the automotive driveline was developed, and the engine torque of the model were evaluated with experimental data. By executing a simulation using the model, it has become possible to obtain the clutch-disc torsional characteristics for reducting the torsional vibration at creeping.

• 한국IT서비스학회:학술대회논문집
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• 2003.05a
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• pp.323-330
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• 2003

현재 국내에서 가장 권위있는 언론상이라고 할 수 있는 한국기자상은 35년이나 되는 전통에도 불구하고 기사의 평가를 위한 명확한 평가기준이 없는 상황이다. 본 연구는 이러한 기사 평가의 명확한 평가기준을 개발하기 위해 국내 외 대표적인 언론상에서 활요하고 있는 평가기준을 종합하여 평가항목을 도출하고, 이를 기반으로 실제 국내에서 수상된 기사를 중심으로 평가항목을 검증하였다. 연구결과, 본 연구에서 도출한 평가항목은 어느 정도 의미를 가지는 것으로 나타났으며, 국내 기자상 선정을 판단할 수 있는 평가항목을 판별분석을 통하여 도출하였다.

• Korea Journal of Hospital Management
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• v.15 no.1
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• pp.93-111
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• 2010

This research is studied for investigative purposes of preparation status for healthcare telematics service enforcement via making an analysis of understanding & expectation effect about healthcare telematics introduction. The study is investigated with two groups, professional medical persons (doctors, nurses, pharmacists) and medical demanders (customers), to analyze the recognition difference between two groups. Questions are carried in face to face interviews by using structured questionnaire & Delphi technique. The survey result shows medical demander's expectation level is higher than the other's at all items such as social changes, medical service provider, medical service users, national and government agencies, medical system suppliers.

• Investigative Magnetic Resonance Imaging
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• v.23 no.2
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• pp.142-147
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• 2019

Piriformis syndrome caused by an accessory belly of the piriformis muscle is very rare. Only a few cases have been reported. Here, we report a case of piriformis syndrome resulting from an extremely rare type of accessory belly of the piriformis muscle originated at the proximal third portion of the main piriformis muscle and attached separately to the greater trochanter inferior to the insertion of the main piriformis muscle. A definitive diagnosis of piriformis syndrome was made based on magnetic resonance imaging and magnetic resonance neurography findings that were consistent with results of nerve conduction study and needle electromyography.

• Investigative Magnetic Resonance Imaging
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• v.23 no.2
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• pp.148-156
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• 2019

Hyperglycemia-induced hemichorea (HGHC) is a rare but characteristic hyperkinetic movement disorder involving limbs on one side of the body. In a 75-year-old woman with a left-sided HGHC, conventional brain MR imaging showed very subtle T1-hyperintensity and unique gadolinium enhancement in the basal ganglia contralateral to movements. Multi-parametric MRI was acquired using pulse sequence with quantification of relaxation times and proton density by multi-echo acquisition. Myelin map was reconstructed based on new tissue classification modeling. In this case report of multi-parametric MRI, quantitative measurement of myelin change related to HGHC in brain structures and its possible explanations are presented. This is the first study to demonstrate myelin loss related to hyperglycemic insult in multi-parametric quantitative MR imaging.

• Archives of Craniofacial Surgery
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• v.20 no.1
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• pp.51-54
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• 2019

Orocutaneous fistulas, or cutaneous sinuses of odontogenic origin, are uncommon but often misdiagnosed as skin lesions unrelated to dental origin by physicians. Accurate diagnosis and use of correct investigative modalities are important because orocutaneous fistulas are easily confused for skin or bone tumors, osteomyelitis, infected cysts, salivary gland fistulas, and other pathologies. The aim of this study is to present our experience with a patient with orocutaneous fistulas of odontogenic origin presenting as recurrent pyogenic granuloma of the cheek, and to discuss their successful treatment.