• 한국멀티미디어학회논문지
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• 제13권9호
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• pp.1357-1364
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• 2010

디지털 방송의 등장으로 다양한 TV 채널들이 시청자에게 제공되고 있지만, 이러한 환경 변화는 오히려 시청자들에게 자신들이 원하는 TV 프로그램을 찾는데 어려움을 겪도록 하고 있다. 이와 같은 어려움을 해소하기 위하여 효율적인 채널 네비게이션 기법(Channel Navigation Scheme)들이 제안되었다. 이 기법들은 시청자의 과거 시청 히스토리 정보를 분석하여 시청자가 선호하는 TV 채널을 예측하고, 시청자가 채널을 변경하고자 할 때 예측된 채널을 제공한다. 기존에 제안된 채널 네비게이션 기법으로는 시청자가 가장 자주 선택한 채널을 제공해 주는 기법인 MFS(Most Frequently Selected)와 가장 최근에 시청한 채널을 제공해주는 기법인 MRS(Most Recently Selected)가 있다. 하지만 MRS, MFS와 같이 시청자의 채널 시청정보에 기반한 방식은 한 채널에서 여러 가지 방송프로그램을 제공하는 현재의 TV 방송에 적합하지 않을 수 있다. 따라서 본 논문에서는 시청자의 채널 시청 정보 대신에 방송프로그램의 시청 정보를 기반으로 채널을 제공해 주는 PMFS(Program Most Frequently Selected)를 제안한다. 또한, 시뮬레이션을 통해 기존의 채널 탐색 기법인 MFS, MRS과 비교하여 PMFS의 탐색 거리(Seek Distance)가 더 짧음을 보인다.

• Journal of Chest Surgery
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• 제51권1호
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• pp.61-63
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• 2018

We report the case of a patient with mitral regurgitation complicated by type B dissection and Marfan syndrome (MFS) who was managed successfully with minimally invasive mitral valve repair. Without type A aortic dissection or aortic root dilation, MFS patients may develop mitral valve regurgitation, as in this case, and need valve surgery to improve their symptoms and long-term survival. However, it is not clear that a full sternotomy and prophylactic aortic surgery are necessary. Although retrograde perfusion to the dissected aorta is controversial, our approach minimizes the risk of future anticipated aortic surgery in MFS patients.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1506-1508
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• 2001

We have investigated for the modeling and the simulation of the ferroelectric capacitor and MFS TFT (Metal-Ferroelectric-Semiconductor Thin Film transistor). For ferroelectric capacitor modeling, we adopted the equivalent circuit model which consists of a nonlear capacitor, a nonliner resistor, and a linear capacitor. MFS TFT have been modeled by combining the ferroelectric capacitor and Bsim3 MOSFET model. Our simulations show the characteristics of ferroelectric capacitor and MFS TFT.

• 대한화학회지
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• 제62권2호
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• pp.79-86
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• 2018

This study reported the adsorption of Cu(II) ions onto activated carbon prepared from Myristica Fragrans shell (MFS AC) over independent variables of contact time, activating chemical (NaOH) concentration, initial adsorbate concentration, initial pH of adsorbate solution and adsorption temperature. The MFS AC structure, morphology and total surface area were characterized by FTIR, SEM and BET techniques, respectively. The Cu(II) ions adsorption on the MFS AC (activated using 0.5 M NaOH) fitted best to Freundlich adsorption isotherm (FAI), and the FAI constant obtained was 0.845 L/g at $30^{\circ}C$ and pH 4.5. It followed the pseudo first order of adsorption kinetic (PFOAK) model, and the PFOAK based adsorption capacity was 107.65 mg/g. Thermodynamic study confirmed the Cu(II) ions adsorption should be exothermic and non-spontaneous process, physical adsorption should be taken place. The total surface area and pore volume based on BET analysis was $99.85m^2/g$ and 0.086 cc/g, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.59-62
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• 1998

Thermal treatment dependences of MFS devices in $BaMgF_4$ on Si structures have been investigated. $BaMgF_4$ thin films have been directly deposited on the p-Si(100) wafers at a low temperature of $300^{\circ}$ in an ultra high vacuum(UHV) system. After in-situ post-deposition annealing was conducted for 20 s at $650^{\circ}$, bias and temperature were applied to $BaMgF_4/Si$ structures. Although X-ray diffraction analysis showed that the films were polycrystalline in nature before and after bias temperature, the C-V properties were some different between with and without bias-temperature treatment.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1996년도 제24회 춘계학술대회
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• pp.145-152
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• 1996

This paper deals with an experimental study on the f~iction torque characteristics of magnctic fluid seals for various oil temperatures, rotating speeds, and vacuum pressures. The friction torque of MFS was measured by high response torque meter. The experimental results show that, as the rotating speed increases, the fi'iction torque of MFS increases and as the oil temperature increases, the friction torque of MFS decreases. Also, the experimental results show that the friction torque of Model II is 1.73 ~ 2.56, 2.0 ~ 2.89, 2.0 - 3.25 times larger than those of Model I under the atmospheric pressure, vacuum pressure(10$^{-4}$ and 10$^{-6}$ torr), respectively.

• Tribology and Lubricants
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• 제13권2호
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• pp.105-111
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• 1997

This paper deals with an experimental study on the friction torque characteristics of magnetic fluid seals for various oil temperatures, rotating speeds, and vacuum pressures. The friction torque of MFS was measured by high response torque meter. The experimental results show that, as the rotating speed increases, the friction torque of MFS increases and as the oil temperature increases, the friction torque of MFS decreases. Also, the experimental results show that the friction torque of Model-II is 1.73~2.56, 2.0~2.89, 2.0~3.25 times higher than those of Model-I under the atmospheric pressure, vacuum pressure ($10^{-4} and 10^{-6}$ torr), respectively.

• 천문학회지
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• 제37권5호
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• pp.427-431
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• 2004

We use simulations of large-scale structure formation to study the build-up of magnetic fields (MFs) in the intergalactic medium. Our basic assumption is that cosmological MFs grow in a magnetohy-drodynamical (MHD) amplification process driven by structure formation out of a magnetic seed field present at high redshift. This approach is motivated by previous simulations of the MFs in galaxy clusters which, under the same hypothesis that we adopt here, succeeded in reproducing Faraday rotation measurements (RMs) in clusters of galaxies. Our ACDM initial conditions for the dark matter density fluctuations have been statistically constrained by the observed large-scale density field within a sphere of 110 Mpc around the Milky Way, based on the IRAS 1.2-Jy all-sky redshift survey. As a result, the positions and masses of prominent galaxy clusters in our simulation coincide closely with their real counterparts in the Local Universe. We find excellent agreement between RMs of our simulated galaxy clusters and observational data. The improved numerical resolution of our simulations compared to previous work also allows us to study the MF in large-scale filaments, sheets and voids. By tracing the propagation of ultra high energy (UHE) protons in the simulated MF we construct full-sky maps of expected deflection angles of protons with arrival energies $E = 10^{20}\;eV$ and $4 {\times} 10^{19}\;eV$, respectively. Accounting only for the structures within 110 Mpc, we find that strong deflections are only produced if UHE protons cross galaxy clusters. The total area on the sky covered by these structures is however very small. Over still larger distances, multiple crossings of sheets and filaments may give rise to noticeable deflections over a significant fraction of the sky; the exact amount and angular distribution depends on the model adopted for the magnetic seed field. Based on our results we argue that over a large fraction of the sky the deflections are likely to remain smaller than the present experimental angular sensitivity. Therefore, we conclude that forthcoming air shower experiments should be able to locate sources of UHE protons and shed more light on the nature of cosmological MFs.

• 전자공학회논문지D
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• 제36D권11호
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• pp.27-32
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• 1999

고온 열처리 시킨 $LiNbO_3/Si$(100) 구조를 이용한 MFS 디바이스를 제작하여 비휘발성 메모리 동작을 확인하였다. 제작한 트랜지스터의 선형영역에서 산출한 전계효과 이동도와 상호 컨덕턴스는 각각 약 $600cm^2/Vs$ 및 0.16mS/mm 이었다. 0.5V의 게이트 전압(즉, read 전압)에서 측정한 드레인 전류의 온/오프 비는 $10^4$배 이상이었다. 분극반전에 사용한 전압은 ${\pm}3V$ 이하로 매우 낮아 이는 저소비전력용 집적회로에 적용시키기에 기대가 된다. 세게 도핑시킨 반도체위에 제작한 MFS 커패시터는 500kHz의 바이폴라 전압펄스(peak-to-peak 6V, 50% duty cycle) 측정으로 $10^{10}$ cycle 까지도 분극의 열화현상이 없는 양호한 특성을 얻었다.

• Clinical and Experimental Pediatrics
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• 제59권2호
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• pp.59-64
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• 2016

Purpose: Infantile Marfan syndrome (MFS) is a rare congenital inheritable connective tissue disorder with poor prognosis. This study aimed to evaluate the cardiovascular manifestations and overall prognosis of infantile MFS diagnosed in a tertiary referral center in Korea. Methods: Eight patients diagnosed with infantile MFS between 2004 and 2014 were retrospectively evaluated. Results: Their median age at the time of diagnosis was 2.5 months (range, 0-20 months). The median follow-up period was 25.5 months (range, 0-94 months). The median length at birth was 50.0 cm (range, 48-53 cm); however, height became more prominent over time, and the patients were taller than the 97th percentile at the time of the study. None of the patients had any relevant family history. Four of the 5 patients who underwent DNA sequencing had a fibrillin 1 gene mutation. All the patients with echocardiographic data of the aortic root had a z score of >2. All had mitral and tricuspid valve prolapse, and various degrees of mitral and tricuspid regurgitation. Five patients underwent open-heart surgery, including mitral valve replacement, of whom two required multiple operations. The median age at mitral valve replacement was 28.5 months (range, 5-69 months). Seven patients showed congestive heart failure before surgery or during follow-up, and required multiple anti-heart failure medications. Four patients died of heart failure at a median age of 12 months. Conclusion: The prognosis of infantile MFS is poor; thus, early diagnosis and timely cautious treatment are essential to prevent further morbidity and mortality.