• Title/Summary/Keyword: Turning pattern

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Evolution of Internal Waves Near a Turning Point in the South China Sea using SAR Imagery and Numerical Models

  • Kim, Duk-Jin;Lyzenga, David R.;Choi, Woo-Young;Kim, Youn-Soo
    • Korean Journal of Remote Sensing
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    • v.23 no.5
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    • pp.385-391
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    • 2007
  • Subsurface Internal Waves(IWs) can be detected in satellite images as periodic alternating brighter/darker stripes. It is known that there are two types of IWs-depression type and elevation type-depending on the water depth in stratified oceans. In this study, we have quantitatively verified the process of converting polarity from depression waves to elevation waves using ERS-2 SAR image acquired over the northern South China Sea. We simulated the evolution of IWs near a turning point with a numerical model for internal wave propagation. The simulation results near the turning point clearly showed us not only a conversion process of IWs from depression to elevation waves, but also a similar wave pattern with the observed SAR image. We also simulated SAR intensity variation near the turning point. The upper layer currents were computed at regular intervals using the numerical model, as the IWs were passing through the turning point. Then, an integrated hydrodynamic-electromagnetic model was used for simulating SAR intensity profiles from the upper layer currents. The simulated SAR intensity profiles were compared with the observed SAR intensities.

Plating hardness and its effect to the form accuracy in shaping of corner cube on cu-plated steel plate using a single diamond tool (단결정 다이아몬드 공구에 의한 Corner Cube 가공 시, 형상정밀도에 미치는 동 도금층의 경도의 영향)

  • Lee, J.Y.;Kim, C.H.;Sea, C.W.
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.5
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    • pp.64-69
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    • 2014
  • This article presents machining experiments to assess the relationship between the profile accuracy and the workpiece hardness using a natural diamond tool on an ultra-precision diamond turning machine. The study is intended to secure a corner cube prism pattern for reflective film capable of high-quality outcomes. The optical performance levels and edge images of corner cubes having various hardness levels of the copper-coated layer on a carbon steel plate are analyzed. The hardness of the workpiece has a considerable effect on the profile accuracy. The higher the hardness of the workpiece, the better the profile accuracy and the worse the edge wear of the diamond tool.

Condition Monitoring of Tool wear using Sound Pressure and Fuzzy Pattern Recognition in Turning Processes (선삭공정에서 음압과 퍼지 패턴 인식을 이용한 공구 마멸 감시)

  • 김지훈
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.10a
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    • pp.164-169
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    • 1998
  • This paper deals with condition monitoring for tool wear during tuning operation. To develop economic sensing and identification methods for turning processes, sound pressure measurement and digital signal processing technique are proposed. To identify noise sources of tool wear and reject background noise, noise rejection methodology is proposed. features to represent condition of tool wear are obtained through analysis using adaptive filter and FFT in time and frequency domain. By using fuzzy pattern recognition, we extract features, which are sensitive to condition of tool wear, from several features and make a decision on tool wear. The validity of the proposed system is condirmed through the large number of cutting tests in two cutting conditions.

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Study on Deburring and Burr Mechanism of Fabricated Micro-Pattern on Cylindrical Workpiece (원통형 공작물에서 미세패턴의 디버링 및 버의 생성 메커니즘)

  • Jin, Dong-Hyun;Lee, Sung-Ho;Kwak, Jae-Seob
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.4
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    • pp.251-255
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    • 2017
  • Burr generation is inevitable during the machining of a micro-pattern, and it is difficult to distinguish between the pattern and burr because they have a very small dimensions. In this study, a micro-pattern with a pitch of $60{\mu}m$and height of $1{\mu}m$ was fabricated on a cylindrical surface using a turning machine. The structure of a burr and its generation mechanism were determined, and a magnetic abrasive deburring process was used to improve the accuracy of the pattern. As a result, when fabricating a micro-pattern, it was shown that the direction of the burr was determined by the feed direction of the tool. The measured pattern height was $1.018{\mu}m$ when the magnetic flux density and spindle speed were respectively 40 mT and 1600 rpm, respectively, during magnetic abrasive deburring, which were determined to be the optimal conditions for processing.

Development of a CAM System for 3-Axis NC Machining for Screws (3축선반에서의 스크류 가공을 위한 CAM 시스템 개발)

  • 이원규;안중환
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.2
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    • pp.21-27
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    • 1998
  • NC machining of large screw which is usually used as a part in an extruder for injection molding is done on 3-axis turning machine, and it is very time-consuming process. Not only in machining but in preparing part program for a NC machine, it requires very long time because the shape of the screw is not easy to model when using an existing general CAD/CAM software even though it is workstation level software. In addition, tool path generation procedure for NC turning for screw shape is also very tedious one because large amount of data for cutter location point must be produced and there is no specific CAM software for the machining. In this paper. development of a CAM system for screw machining which saves the role of CAD software by use of menu driven data input system for various screw shapes is introduced.

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DOE 렌즈 개발 현황과 전망

  • 김영준
    • The Optical Journal
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    • v.13 no.5 s.75
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    • pp.20-22
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    • 2001
  • 향후 초박형 렌즈에 있어서 플라스틱 DOE Lens가 주도적으로 사용될 전망이고, 광통신분야에서도 WDM(wavelenght Division Multiplexer)등에 응용 가능성이 높다. DOE Pattern의 회절광량 해석기술, DTM(Diamond Turning Machine)과 Laser가공기의 정밀도 향상 등으로 금형가공기술의 급속한 발전과 함께 DOE의 보편화는 조만간 이뤄질 것으로 보인다.

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Health Experience of Depressive Adolescents: Reflected from Newman's Praxis Methodology (우울 청소년의 건강경험 - Newman의 실무연구방법론을 근거로 -)

  • Kweon, Young-Ran;Lee, Chung-Sook
    • Journal of Korean Academy of Nursing
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    • v.39 no.2
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    • pp.217-228
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    • 2009
  • Purpose: Guided by Newman's theory of health as expanding consciousness, this study was done to explore the health experience of adolescents having depression. Methods: The researcher engaged in six to eight in-depth interviews with six adolescents. To begin the dialog, the researcher asked each participant to recount the first important memory he/ she had. All the narrative and diagram sharing between the researcher and participants were summarized according to recognized patterns and later elaborated in following interviews based on Newman's praxis methodology. Results: The significant individual pattern of early health experience was during the binding stage. At the turning point, individual patterns for participants revealed a personal journey of self-discovery and then emergence of reflecting behaviors. After the turning point, the participants changed as they evolved from the initial period of disruption and disorganization to organization at a higher level. The results suggest that adolescents who are depressive find new ways of relating to friends, family, healthcare providers, and the community by expanding their consciousness. Conclusion: Newman's praxis methodology is a good way of helping and studying adolescents with depression because it emphasizes participant-nurse/researcher partnership and pattern recognition as nursing practice.

A Study on Health as Expanding Consciousness of Korean Elderly People with Chronic Illnesses in the Community (만성질환노인들의 의식확장으로서의 건강연구)

  • Kang, Hae-Young
    • Research in Community and Public Health Nursing
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    • v.11 no.1
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    • pp.172-183
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    • 2000
  • This paper explores the process of pattern recognition reflected in Newman's praxis methodology by three Korean elderly people with chronic illnesses. Four core themes demonstrated from the life pattern of participants that discouragement/frustration, regret, deep grudge/ pent up feeling and renunciation/ resignation were prevalent. None of the participants had experienced the turning point central to the process of expanding consciousness. It was concluded that it requires longer a research period with repeated in-depth interviews to explore the transformation in the process of recognizing a pattern of life.

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A Study on the Development of Body Measuring Tool for Tight-fit Type Clothing Construction (타이트피트형 의복설계를 위한 계측기 개발에 관한 연구)

  • 조덕남;나미향;정복희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.4
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    • pp.530-537
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    • 2000
  • The purpose of this study is to develop the measuring tool that can grasp the relationship between body and pattern, the result can be directly digitalized and developed as the pattern as body form is. There are 6 measurements; 1) the width of front and rear neck 2) the slant degree of shoulder 3) the degree of protrusion of breasts and scapulae 4) the separation of front and rear board 5) space between body and clothes 6) vertical strand in the clothes Developed measuring tool is handy in un. in which points of body to be measured are small, and it has the capability of designing the high fitness for body. The measurer developed through this study is named as $\ulcorner$Somato-pattern Measurer$\lrcorner$, size paper is named$\ulcorner$Somato-pattern Paper$\lrcorner$and the pattern made by$\ulcorner$Somato-pattern Measurer$\lrcorner$is named$\ulcorner$Somato-pattern$\lrcorner$respectively by our team. The result of this study is thought to make a great contribution to solving the various problems which can be derived in the time of pattern design because of the difference of physical forms in the same size as well as the difference between the factor of size and that of form in body.

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