• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1993년도 하계학술대회 논문집 B
• /
• pp.945-947
• /
• 1993

This paper presents the numerical algorithm that can obtain the surface configuration of the magnetic fluid seals. The magnetic field is computed by nonlinear finite element method considering the saturation of magnetic fluid and pole piece. The surface equilibrium condition in ferrohydrodynamics are used in algorithm. The influence of the surface configuration on the sealed pressure due to the magnetic, centrifugal and gravitational forces is analyzed and compared with other experimental results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
• /
• pp.1059-1061
• /
• 2005

The bushing currently applied to pole-mounted type loadbreak switch has porcelain bushing which is connected with the mold cone. This type has potential problems of uncertainty of sealing of the interface part and gas leakage on the connected part between bushing and switch tank due to the weight of the porcelain. The Composite Bushing can solve these problems and also the secondary problem of the potential accident owing to the fragment of the porcelain bushing in breakage due to the outer impact.

• 한국정밀공학회지
• /
• 제24권9호
• /
• pp.95-102
• /
• 2007

The scanning electron microscope (SEM) is one of the most popular instruments available for the measurement and analysis of the micro/nano structures. It is equipped with an electron optical system that consists of an electron beam source, magnetic lenses, apertures, deflection coils, and a detector. The magnetic lenses playa role in refracting electron beams to obtain a focused spot using the magnetic field driven by an electric current from a coil. A SEM column usually contains two condenser lenses and an objective lens. The condenser lenses generate a magnetic field that forces the electron beams to form crossovers at desired locations. The objective lens then focuses the electron beams on the specimen. The present work concerns finite element analysis for the electron magnetic lenses so as to analyze their magnetic characteristics. To improve the performance of the magnetic lenses, the effect of the excitation current and pole-piece design on the amount of resulting magnetic fields and their peak locations are analyzed through the finite element analysis.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2013년도 춘계학술대회 논문집
• /
• pp.835-841
• /
• 2013

Modern solid-state gyroscopes (HRG) with hemispherical resonators from high-purity quartz glass and special surface superfinishing and ultrathin gold coating become the best instruments for precise-grade inertial reference units (IRU) targeting long-term space missions. Designing of these sensors could be a notable contribution into development of Korea as a space nation. In participial, 40mm diameter thin-shell resonator from high-purity fused quartz, fabricated as a single-piece with its supporting stem has been designed, machined, etched, tuned, tested, and delivered by STM Co. (ATS of Ukraine) several years ago; an extremely-high Q-factor (upto 10~20 millions) has been shown. Understanding of the best way how to match such a unique sensor with inner glass assembly of the gyro means how to use the high potential in a maximal extent; and this has become the urgent task. Inner quartz glass assembly has a very thin indium (In) layer soldered the resonator and its silica base (case), but effects of internal resonances between operational modal pair of the shell-cup and its side (parasitic) modes can notable degrade the potential of the sensor as a whole, instead of so low level of resonator's intrinsic losses. Unfortunately, there are special combinations of dimensions of the parts (so-called, "resonant sizes"), when intensive losses of energy occurs. The authors proposed to use the length of stem's fixture as an additional design parameter to avoid such cases. So-called, a cyclic scheme of finite element method (FEM) and ANSYS software were employed to estimate different combinations of gyro assembly parameters. This variant has no mismatches of numerical origin due to FEM's discrete mesh. The optimum length and dangerous "resonant lengths" have been found. The special attention has been paid to analyses of 3D effects in a cup-stem transient zone, including determination of a difference between the positions of geometrical Pole of the resonant hemisphere and of its "dynamical Pole", i.e., its real zone of oscillation node. Boundary effects between the shell (cup) and 3D short "beams" (inner and outer stems) have been ranged. The results of the numerical experiments have been compared with the classic model of a quasi-hemispherical shell band with inextensional midsurface, and the solution using Rayleigh's functions of the $1^{st}$ and $2^{nd}$ kinds. To guarantee the truth of the recommended sizes to a designer of the real device, the analytical and FEM results have been compared with experimental data for a party of real resonators. The consistency of the results obtained by different means has been shown with errors less than 5%. The results notably differ from the data published earlier by different researchers.

• Archives of Plastic Surgery
• /
• 제38권5호
• /
• pp.559-566
• /
• 2011

Purpose: The use of tissue expander/implant in breast reconstruction using tissue expander-implant is one of the most common surgical procedures. The use of AlloDerm as a sling to reestablish the lower pole of the pectoralis major muscle results a decrease in morbidity compared with more invasive procedures. However the use of AlloDerm is more expensive than other options. We decided to compare AlloDerm with Permacol, which has been safely used in human body reconstruction and is less costly than AlloDerm. Methods: After mastectomy, the inferolateral origin of the pectoralis major muscle was elevated. Either AlloDerm or Permacol was sutured to the chest wall at the level of the previously marked inframammary fold. The lower border of the pectoralis major muscle and the upper portion of the crescent-shaped piece of either AlloDerm or Permacol was sutured together using a tension free technique, and a tissue expander was subsequently inserted into the subpectoral-subAlloDerm (or Permacol) dual pocket. Results: AlloDerm was used in twenty-one patients (28 breasts) and Permacol was used in six patients (11 breasts) for tissue expander-implant breast reconstruction. During the mean follow-up period of 17 months (8~25 months). Two infections (7%) occurred in AlloDerm cases and four infections (36%) occurred in Permacol cases. Conclusion: This study is the first comparison of tissue expander/implant breast reconstruction using AlloDerm and Permacol. The use of Permacol resulted in more postoperative infection compared with the use of AlloDerm. This report is still limited with the small number of cases studied.

• 비교문화연구
• /
• 제43권
• /
• pp.327-354
• /
• 2016

랭보의 산문시집 "일뤼미나시용"의 "야만"은 형식이나 주제, 비유 등이 난해한 시로 유명하다. 본고는 작품의 난해성을 연구하기 위해 먼저 문법적 구조를 분석하였고, 그런 다음 시의 의미를 살펴보기 위해 저자의 다른 작품과 비교하는 자기텍스트성을 분석하였다. 자기텍스트성은 스티브 머피가 제시한 랭보 산문시 해석의 방법론으로서 저자의 작품과 맺는 내적 상호텍스트성을 말한다. "야만"의 경우 일반적 상호텍스트성의 연구가 없는 것은 아니지만 시의 의미를 크게 규명하지 못한다고 본다. "야만"의 난해성은 무의미 시의 예로 간주되기도 한다. 하지만 시 구조 분석과 자기텍스트성을 통해 볼 때, "야만"은 무의미가 아니라 의미를 구축하고 있다. 이 시는 일반적 운문시나 산문시와 달리 전체가 명사 구문의 비유로만 이루어져 있다. "야만"은 랭보 고유의 문맥에서 파괴, 화합, 재생의 순수한 힘을 의미한다. "야만"은 보들레르의 "이 세상 끝 어디라도"에 대한 랭보 식 답으로, 북극의 불카누스의 화산에 도달하는 영원한 여성의 목소리로 대변되는 현장이라 할 수 있다. "야만"의 읽기는 "일뤼미나시용"의 난해성을 읽어내는 하나의 방법론이 될 수 있다. 본고에서 우리는 "야만"의 언어적 지표의 분석과 자기텍스트성, 그리고 시가 침묵하고 있는 희열과 고독의 이해가 하나의 접근법이 될 수 있음을 분석하였다. 이러한 접근법을 통해 우리는 "일뤼미나시용"의 파편을 개개의 방식으로 연결하고 조합해서 파편들의 스토리를, 모험을 재구성할 수 있으리라 본다.