• 한국레이저가공학회지
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• 제18권3호
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• pp.6-8
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• 2015

Finishing process includes deburring, polishing and edge radiusing. It improves the surface profile of specimen and eliminates the alien substance on surface. Deburring is the elimination process for debris of edges. Polishing lubricates surfaces by rubbing or chemical treatment. There are two types for electron finishing. The one is using pulse beam. The other is using the convergent and scanning electron beam. Pulse type device appropriates the large area process. But it does not control the beam dosage. Scanning type device has advantages for dosage control and edge deburring. We design the convergence and scan type. It has magnetic lenses for convergence and scan device for scanning beam. Magnetic lenses consist of convergent and objective lens. The lenses are designed by the specification(beam size and working distance). In this paper, we evaluate the convergence performance by pattern process. Also, we analysis the results and important factors for process. The important factors for process are beam size, pressure, stage speed and vacuum. These results will be utilized into systematizing pattern shape and the factors.

• 한국군사과학기술학회지
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• 제20권1호
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• pp.98-107
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• 2017

Electric components equipped with naval shipboards must endure mechanical shock caused by various mechanical impulsive sources. Thus the components must be designed carefully and reliability test is an essential procedure before use. In this study, a new design technology applicable to a large and heavy shock generation system which can generate various specific real mechanical shocks in specified time domain was introduced. Commonly, the shock transmitted through the wall of naval shipboard consists of dual shocks. The primary shock is of a very high amplitude and very short period half-sine form. The following shock is of an exponentially decaying harmonic form of relatively longer period. Based on the different dynamic characteristics of two shocks, we proposed a sequential design procedure to determine spring and damping coefficients of the generation system. Some numerical simulation results showed the feasibility of the proposed method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.30-32
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• 1994

In this paper, in order to design Linear Pulse Motor(LPM) effectively, the flux density and the thrust force of LPM have been calculated in the air gap by using Finite Element Method(FEM). The kinds of magnetic circuit arc the variable reluctance(VR), hybrid(HB), and permanent magnet(PM) type. Tooth and slot shape arc rectangular, wedge head(tapcr; 10, 20 degree), and semi-circle type.

• Bulletin of the Korean Chemical Society
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• 제5권2호
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• pp.79-82
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• 1984

This study concerns about catalyic cracking of iso-octane over cation ($Cd^{2+},\;Ca^{2+}\;and\;La^{3+}$) exchange mordenites. It deals with mordenite shape selectivity and with kinetics of this catalytic reaction. The striking feature was that over the region of cracking temperature investigated, 523-665K, the yield of isobutene was predominant, relative to that of larger or smaller carbon chain(s). This permits kinetic analysis of the heterogeneous catalytic system in terms of the modified pulse-version microcatalytic chromatography. The observed activation energy ($E_a,\;KJ\;mol^{-1}$) was found to be 46 for Cd-M, 57 for Ca-M and 59 for La-M, respectively.

• 대한전자공학회논문지TC
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• 제39권3호
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• pp.150-157
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• 2002

펄스 안테나로 많이 사용되는 종래의 직선형 혹은 V-형 안테나의 원거리전장은 null점들을 갖는 주파수 특성을 가지므로 제한된 펄스 복사 능력을 가진다. 이를 개선시키기 위해 비선형적 형상을 갖는 와이어안테나의 합성법을 제안하였다 즉, 복사 전장의 주파수 의존성을 최소화시키는 형상방정식을 유도하고 그 해를 산출하므로서 리플형의 광대역 특성을 갖는 형상을 합성하였다. 그 결과 매우 넓은 주요 스펙트럼을 갖는 짧은 펄스의 복사에 유리함을 보였다. 따라서, 펄스폭이 좁을수록 합성된 다이폴 안테나 특성이 종래의 선형 다이폴 보다 우수한 피크치를 갖는 펄스 복사가 이루어짐을 보였다. 전류 분포 및 원거리 전장의 과도해석을 위해 모멘트법에 기반한 역 이산 푸리에 변환을 사용하였다.

• 대한한의진단학회지
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• 제11권2호
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• pp.1-12
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• 2007

Objectives: The aim of the present investigation was to determine whether the finger photoplethysmographic waveform of a healthy young man will become analogous to those of healthy old men when the photoplethysmographic harmonic components in the young man decrease. Methods and Results: The finger photoplethysgmoraphy was measured in 21 old men over the age of 60 years and a young men. We acquired the representative pulse waveform of old man by averaging the finger photoplethysmographic waveforms measured in the old men. after the photoplethysmographic harmonic components in the young man were diminished with notch filtering, we compared the representative pulse waveform of old man and the pulse waveforms of which the harmonic components decreased in the young man. The finger photoplethysmographic waveform of the young man became analogous to those of the old men as the photoplethysmographic harmonic components in the young man were diminished with notch filtering. Conclusions: Decrease of the second harmonic component may be a precondition of typical age-related change of the pulse waveform.

• 동국한의학연구소논문집
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• 제8권2호
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• pp.131-154
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• 2000

<난경(難經)>은 <내경(內經)>의 사상(思想)을 보다 자세(仔細)하고 심도(深度)있게 문답(問答)을 가설(假說)하여 의난(疑難)을 해석하는 방식으로 편찬된 서적(書籍)으로써, 논술(論述)은 기초이론(基礎理論)을 위주로 하고, 또 일부 병설(病說)도 분석(分析)하였는데 그 내용이 간요(簡要)하며, 변석(辨析)이 매우 정미(精微)하게 되어있다. 그 중 1-23난(難)은 맥(脈)을 논(論)하고, 23-29난(難)은 경락(經絡)을 논(論)하고, 30-47난(難)은 장부(臟腑)를 논(論)하고, 48-61난(難)은 병(病)을 논(論)하고, 62-68난(難)은 혈도(穴道)를 논(論)하고, 69-81난(難)은 침법(鍼法)을 논(論)하였다. 특히 <난경(難經)>에는 진법(診法)으로써 오늘날까지 한의학의 맥진방법(脈診方法)으로써, 가장 많이 응용되고 있는 '독취촌구법(獨取寸口法)'을 명확하게 밝히고 있다. 이에 본(本) 저자(著者)는 <난경(難經)>의 맥론(脈論)에 대한 이해를 높이기 위하여 <난경지연구(難經之硏究)>를 중심으로 1-23난(難)에 나오는 맥론(脈論)들을 정리하여 다음과 같이 정리하였다. 팔십일(八十一) 난경중(難經中) 일난(一難)부터 삼십삼난(三十三難)까지의 맥학(脈學)에 관(關)한 조문중(條文中)에는, 백맥(百脈)이 조회(朝會)하고 그 시작(始作)과 끝이 되는 촌구(寸口)를 중심개념(中心槪念)으로 하고 정상적(正常的)인 생리적(生理的) 맥(脈)과 병적(病的)인 맥(脈)이 대비(對比)되면서 제시(提示)되어있다. 1. 십난(十難)에서 오사(五邪)와 강유(剛柔)의 이론(理論)과 각(各) 장부(臟腑)의 고유(固有)한 맥상(脈狀)이 등장(登場)하고 있다. 2. 십삼난(十三難)에서는 색(色)과 맥(脈), 형육(形肉)의 세가지 요소(要素)가 상응(相應) 또는 상승(相勝)하는가에 따라서 병(病)의 난(難) 역치(易治)를 결정(決定)한다고 하였다. 3. 십사난(十四難)에서는 맥(脈)을 손(損)(지맥(遲脈))과 지(至)(수맥(數脈))으로 구분하는데, 맥(脈)의 손(損)에 따른 이경(離經), 탈정(奪精), 사(死), 절명(絶命)의 구분(區分)과, 맥(脈)의 지(至)에 따른 이경(離經), 탈정(奪精), 사(死), 절명(絶命)을 구분(區分)을 설명(說明)하였다. 4. 십오난(十五難)에서는 현(弦), 구(鉤), 모(毛), 석맥(石脈)으로 사시(四時)에 따라서 맥(脈)이 다르다는 것을 말하였다. 이와같이 난경(難經)에서는 "독취촌구(獨取寸口)"의 맥법(脈法)을 명화(明確)하게 확립(確立)하였으며, <내경(內經)>의 이론(理論)을 더욱 다져서 진일보(進一步)시키면서도 <내경(內經)>과는 다른 독창적(獨創的) 이론(理論)을 제시(提示)한 것이 <난경(難經)>의 가치(價値)를 더하게 하였다.

• 한국표면공학회지
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• 제49권2호
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• pp.111-118
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• 2016

A method to quantitatively analyze the defects formed by the hydrogen evolution during electroplating was suggested based on the theoretical approach of the small angle neutron scattering technique. In case of trivalent chrome layers, an isolated defect size due to the hydrogen evolution was about 40 nm. Direct and pulse plating conditions gave the average defect size of about 4.9 and $4.5{\mu}m$ with rod or calabash shape, respectively. Current density change of the pulse plating from $1.5A/dm^2$ to $2.0A/dm^2$ enlarged the average defect size from 3.3 to $7.8{\mu}m$. The defect morphology like rod or calabash was originated by inter-connecting the isolated defects. Small angle neutron scattering was useful to quantitatively evaluate defect morphology of the deposit.

• 한국소음진동공학회논문집
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• 제14권11호
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• pp.1075-1082
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• 2004

This research demonstrates the shock response analysis of a head disk assembly subjected to a half-sine shock pulse in the axial direction. In case of disk analysis, the numerical method presented by Barasch and Chen is used. Galerkin method is used with mode shape by numerical method. Head-suspension system is modeled as the cantilever in order to get simulation results. Simulation results of HDA are calculated by Runge-Kutta method. Finally, shock responses of head and disk are analyzed according to the change of the rotating speed of the disk.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.897-899
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• 2000

This paper deals with the dynamic characteristic analysis of Linear Oscillatory Actuator (LOA) considering Sine Pulse Width Modulation (SPWM) method with H-bridge driver. The input current shape obtained by the driver has great influence on the driving performance of LOA. Therefore, according to the various current shapes, the analysis is achieved by using the combined equation between kinetic and electric circuit equation. Moreover, the parameters in the electric circuit equation are accurately estimated by using FEM.