• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.208-213
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• 2003

A note-book PC has become thinner in recent years. And optical disc drives are required to have high memory capacity. Therefore, the actuator of optical disc drives must be thinner and have disc tilt compensation function for high density memory. In this paper, the hybrid type actuator is investigated for 3-axis ultra-slim actuator. A 3-axis ultra-slim actuator is designed by using the modal analysis of the actuator and the electromagnetic analysis of magnetic circuit to achieve dynamic characteristics and magnetic flux density for high sensitivity, respectively. Also, magnetic force between tilt magnet and tilt yoke is investigated to find the influence on the DC sensitivity in the focus and track directions.

• International Journal of Precision Engineering and Manufacturing
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• 제4권4호
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• pp.5-12
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• 2003

This paper discusses about the thickness effects on the structural durability of a bileaflet mechanical heart valve (MHV). In the study on the design and the mechanical characteristics of a bileaflet mechanical heart valve, the fluid mechanics analysis on the blood flow passing through leaflets, the kinetodynamics analysis on the rigid body motion of the leaflet induced by the pulsatile blood flow, and the structural mechanics analysis for the deformed leaflet are required sequentially and simultaneously. Fluid forces computed in the fluid mechanics analysis on the blood flow are used in the kinetodynamics analysis for the leaflet motion. Thereafter, the structural mechanics analysis for the deformed leaflet follows to predict the structural strength variation of the leaflet as the leaflet thickness changes. Analysis results show that structural deformations and stresses increase as the fluid pressure increases and the leaflet thickness decreases. Analysis results also show that the leaflet becomes structurally weaker and weaker as the leaflet becomes thinner and thinner.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.51-54
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• 2003

We investigated the quench characteristics of thin film type SFCLs with shunt layers of various thickness. The SFCLs ware based on 2 inch diameter YBa$_2$Cu$_3$O$_{7}$ thin films coated in-situ with a gold shunt layer. The shunt layer thickness was varied by Ar ion milling. The limiters were tested with simulated fault currents at various source voltages. The thinner the shunt layer was, the slower was the rise of SFCL temperatures. This means SFCLs of thinner shunt layers had higher voltage ratings. The voltage rating was approximately inversely proportional to the square root of the shunt layer thickness. This result could be understood through the concept of heat balance.e.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.242-245
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• 2003

We investigated the quench characteristics of thin film type SFCLs with shunt layers of various thickness. The SFCLs ware based on 2 inch diameter YBa$_2$Cu$_3$3O$_{7}$ thin films coated in-situ with a gold shunt layer. The shunt layer thickness was varied by Ar ion milling. The limiters were tested with simulated fault currents at various source voltages. The thinner the shunt layer was, the slower was the rise of SFCL temperatures. This means SFCLs of thinner shunt layers had higher voltage ratings. The voltage rating was approximately inversely proportional to the square root of the shunt layer thickness. This result could be understood through the concept of heat balance.e.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.421-424
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• 2005

Discusses the results of an investigation of the relationship between maturity in field-cured specimens and that from the thinner dimension structure to thick, particularly at cold weather concrete. Tests were carried out on two different concrete mixes with 28 day compressive strengths ranging approximately 30MPa. Ready-mixed concrete was used, and test specimens were the conventional field-cured 10$\times$20cm concrete cylinder with insulating materials and without them, and test structures were the thinner(width 20cm), the general(width 40cm), the thick dimension(width 60cm), respectively. Tests were performed at age of 3, 7, 14, 28 day. Analyses of test results show that the maturity of concrete for require compressive strength was suggested to be keep higher than $164D^{circ}D$ until at least from 8day to 10day

• 대한치과교정학회지
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• 제15권1호
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• pp.149-153
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• 1985

The purpose of this study was to pursue the morphology and position of mandibular symphysis and the positioning of lower incisors in 36 male and female adults with severe skeletal Class III malocclusion indicated for surgical orthodontic treatment. The following results were obtained. 1. Skeletal Class III malocclusion samples had thinner labio-lingual depth and more lingual inclination of mandibular symphysis than that of normal occlusion in both sexes. 2. Male and female with the skeletal Class III malocclusion showed marked lingual tipping of lower incisors. 3. In skeletal Class III malocclusion samples, lingual basal bone was thinner than that of normal occlusion in both sexes.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1995년도 추계학술강연 및 발표대회 강연 및 발표논문 초록집
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• pp.6-8
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• 1995

Among powder metallurgy products, complex shaped parts are difficult to be produced. Even i9f it shall be compacted until pet shape, the parts are easily apt to crack. thus it causes inferior productivity.It is present condition that net ahaped parts are obtained by adding after treatment. Clutch hub, pulley, representative partawifh upper 2 steps, tower 3 steps parts are corresponded to the above case. In recent years. muired parts are get to be thinner and thinner, and therefore extremely high compacting techniaues are required. Definition of most preferable com~actingp arts are I) Uniform density 2) Non crack and 3) Realization of net shape or near net shape productlon. For the above purpose, YOSHIZUKA baa developed n now oreas applying hydraulic servo control system.

• 한국안전학회지
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• 제20권3호
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• pp.42-46
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• 2005

The static electricity by thinner flow and discharge energy is investigated experimentally for the purpose of preventing the electrostatic discharge and damage. Test system for evaluating streaming electrification consists of a teflon pipe, a reservoir tank a pump, flowmeters and an electrometer. When dielectric liquid flows through a pipe from one vessel to another, the potential difference generated in the collecting vessel is due to the accumulation of charges. These charges result from the convection of a part of the electrical double layer existing in the tube at the contact between the liquid and the inner wall. When the fluid velocity increases, the electric current increases proportionally. The charging current and accumulated charges by streaming electrification at the thinner velocity of 40cm/s are measured a range of 5 nA and $0.27{\mu}C$ respectively. This amount of static discharge energy generated by streaming electrification is enough to ignite flammable solvent. Therefore surface electric potential should decrease by using electrostatic shielding and ground.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.348-348
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• 2005

High capacitance MLCC has been enabled through the use of nickel electrodes to produce thinner layers at acceptable costs. High capacitance MLCC devices offer significant advantages to electrolytics such as tantalum and aluminum ; Lower ESR for high frequency applications. Non-polarized. Many process improvement have enabled this technology Higher dielectric constants Thinner dielectric and electrode layers through BME More accurate layer construction. This study is high capacitance MLCC electrical propertics. reliability, Analysis on DOE(Design Of Experiment) of the electical propertics.

• 한국표면공학회지
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• 제33권4호
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• pp.217-221
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• 2000

The gate oxide thickness is becoming thinner and thinner in order to speed up the semiconductor CMOS devices. We have investigated very thin$ SiO_2$ gate oxide layers and found anomaly between the thickness determined with capacitance measurement and these obtained with cross-sectional high resolution transmission electron microscopy. The thicknesses difference of the two becomes important for the thickness of the oxide below 5nm. We propose that the variation of dielectric constant in thin oxide films cause the anomaly. We modeled the behavior as (equation omitted) and determined $\varepsilon_{bulk}$=3.9 and $\varepsilon_{int}$=-4.0. We predict that optimum $SiO_2$ gate oxide thickness may be $20\AA$ due to negative contribution of the interface dielectric constant. These new results have very important implication for designing the CMOS devices.s.