• Title/Summary/Keyword: non-contacting

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A Review of Performance and Safety Law for Maglev Vehicle (자기부상철도 성능 및 안전 관련법 검토)

  • Chang, Seok-Gahk;Lee, Young-Hoon;Byun, Youn-Seop
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.1140-1141
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    • 2006
  • Maglev is a non-contact traffic system in which cars are supported by magnetic force instead of wheels. This is a ground-breaking traffic system providing superior environmental friendliness and cost efficiency due to the minimal noise and vibration offered by its non-contacting nature. We study the present specification and performance of the low speed urban maglev system in Korea and other countries. After set up the test line, to success the "Commercialization of Korean Urban Maglev System" project, we establish proper requirement of maglev system in Korean environment on base of "Daejeon National Science Museum Maglev Establish Project".

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Design and analysis of a newly devised linear flexure bearing(KIMM-Ml) for cryogenic compressors (극저온 냉동기 헬륨 압축기용 선형 탄성 베어링의 해석 및 설계)

  • 조영선;최상규;박성제;김효봉;우호길
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.1091-1098
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    • 2003
  • Flexure bearings have been used in linear-resonant compressors to maintain a non-contacting clearance seal between the piston and cylinder. There are two types of tangential cantilever bearing and spiral arm bearing with flexure bearings. A newly devised linear flexure bearing (KIMM-Ml) for compression refrigeration machines is disclosed having improved tight gas clearance maintaining capability for better system performance. KIMM-Ml is an integrated device comprising an axially moving diaphragm with circumferentially arranged arc-shaped flexure blades secured between rim and hub spacers, which turn out to have higher radial stiffness than the one with circumferential tangential cantilever flexure blades. It is expected for KIMM-Ml to play a key role in designing long life, special purpose compression refrigeration machines by providing frictionless, non-wearing, linear movement and radial support for the machines as well as a gas clearance seal by maintaining extremely tight clearances between piston and cylinder.

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A Study on Geometrical Glue Operation between Non-manifold Models (비다양체 모델간의 기하학적 접합 연산에 관한 연구)

  • Park, Sang-Ho
    • Journal of the Korea Computer Graphics Society
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    • v.4 no.1
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    • pp.11-19
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    • 1998
  • Non-manifold topological operations such as Euler and Boolean operations provide a versatile environment for modeling domains. The implementation of these operations raises geometrical issues that need to be addressed to ensure the topological validity of the underlying model, and they uses the glue operation which provides a basic method to modify the topology of non-manifold models when vertices, edges and faces are contacting each other. Topological information such as adjacency relationships should be inferred when gluing non-manifold models. Two methods of reasoning can be employed to find the topological information : topological reasoning and geometrical reasoning. The topological method can infer the adjacency relationships by using stored topological information. On the other hand, the geometrical method can find topological ambiguities by considering the geometrical shape at the local area of gluing when the topological relations were not stored. This paper describes the geometrical reasoning method.

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Non-Contact Level on Air Levitation Table with Porous Chamber Array (다공성 패드를 갖는 챔버의 배열에 따른 공기 부상 테이블의 비접촉 부상 수준에 대한 연구)

  • Kim, Joon Hyun;Jeong, Young Suk;Lee, Tae Geol;Kim, Tae Hoon;Jung, Hyo Jae
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.6
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    • pp.913-920
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    • 2013
  • This paper presents an applicable basic design that can configure non-contact levitation table for conveying a large sheet of glass. The suggested air levitation table consists of a series of air chambers with porous pads and fans as the conveyor system. The air supply chambers are arrayed to supply an adequately strong upward airflow for supporting the glass. Levitation is controlled by the size and discharge velocity, of the chamber arrays, as well as the glass supporting height. After pre-evaluation of the glass rigidity and the filer functional performance, a one-way fluid structure interface (FSI) analysis is performed for predicting pressure and deflection working of the 8G glass in the transverse and longitudinal directions, respectively. After comparing calculated levels of flatness of the glass, it determines the chamber array for the linear non-contact conveying motion.

A study on Non-contacted Transmitter Switch for Vehicle (비 접촉식 차량용 Transmitter Switch에 관한 연구)

  • Ahn, Jong-Young;Kim, Young-Sub;Kim, Sung-Su;Hur, Kang-In
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.5
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    • pp.245-249
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    • 2010
  • Now normally using a contact method of vehicle Inhibitor Switch that is use direct voltage level signal. This method is good solution for signal deliverly. but The contacted method have a short lifetime because of deterioration of contact surface. so we suggest to non-contacted method using magnetic sensor. The magnetic sensor is used to non-contacted method that is solution for problem of contacted method. In this paper using that of magnetic sensor feature, so we applied to Vehicle Transmitter switch that of non-contacting method. Sensor voltage outputs have variable electric potential that normally 0 mV to 150 mV, and it is depend on Switch Angle. we used two differential sin wave for switching of 5 state signal.

Design of the Air Pressure Pick-up Head for Non-Contact Wafer Gripper (비접촉식 웨이퍼 그리퍼용 공압 파지식 헤드 설계)

  • Kim, Joon-Hyun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.3
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    • pp.401-407
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    • 2012
  • The recent manufacturing process in the thin wafers and flat panel necessitate new approaches to reduce handling fragile and surface-sensitive damage of components. This paper presents a new pneumatic levitation for non-contact handling of parts and substrates. This levitation can achieve non-contact handling by blowing air into an air pressure pick-up head with radial passages to generate a negative pressure region. Negative pressure is caused by the radial air flow by nozzle throat and through holes connecting to the bottom region. The numerical analysis deals with the levitational motion with different design factors. The dynamic motion is examined in terms of force balance(dynamic equilibrium) occurring to the flow field between two objects. The stable equilibrium position and the safe separation distance are determined by analyzing the local pressure distribution in the fluid motion. They make considerable design factors consisting the air pressure pick-up head. As a result, in case that the safe separation distance is beyond 0.7mm, the proposed pick-up head can levitate stably at the equilibrium position. Furthermore, it can provide little effect of torque, and obtain more wide picking region according to the head size.

A Comparison Study on Multicultural Attitude and Relating Factors of Nursing College Students and Non-Nursing Major Students in Korea (간호대학생과 타전공 일반대학생의 다문화태도 및 관련요인에 관한 비교연구)

  • Kim, Mijong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.4
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    • pp.2310-2319
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    • 2014
  • The study was to investigate the multicultural attitude of nursing students and non-nursing major students. And it was explored influencing factors related with it. This study was used a descriptive comparative designed. Data were collected 3 universities in D city in from Nov. to Dec. in 2012. After receiving the agreement, 309 nursing students and 195 non-nursing major students were recruited. They were asked to fill in a self-reported questionnaire about multicultural attitude. The Korean version Munroe Multicultural Attitude Scale Questionnaire (MASQUE) was used. Cronbach's alpha were .85. Data were analyzed by SPSS 18.0. The mean score of multicultural attitude was 4.44 of 6 points(73%) in all participants. Nursing students' multicultural attitudes scores were equal to other college students'. The factors related to multicultural attitude were the experiences of having foreigner friends, going abroad, attending multicultural events, and contacting multicultural contents. The students who have cared foreign patients were not higher than others in nursing students group(t=.30, p=.76). For nursing students contacting foreigners in clinical practice, it doesn't make a differnce in multicultural attitude. The culturally empowering programs were needed for nursing students to improve multicultural attitudes.

Development of Laser-Based Resonant Ultrasound Spectroscopy(Laser-RUS) System for the Detection of Micro Crack in Materials (재료의 미세결함 검출을 위한 레이저 공명 초음파 분광(Laser-RUS)시스템 개발)

  • Kang, Young-June;Kim, Jin-Soo;Park, Seung-Kyu;Baik, Sung-Hoon;Choi, Nag-Jung
    • Journal of the Korean Society for Precision Engineering
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    • v.27 no.1
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    • pp.41-48
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    • 2010
  • Non-contacting, laser-based resonant ultrasound spectroscopy (L-RUS) was applied to characterize the microstructure of a material. L-RUS is widely used by virtue of its many features. Firstly, L-RUS can be used to measure mechanical damping which related to the microstructural variations (grain boundary, grain size, precipitation, defects, dislocations etc). Secondly, L-RUS technology can be applied to various areas, such as the noncontact and nondestructive quality test for precision components as well as noncontact and nondestructive materials characterization. In addition, L-RUS technology can measure the whole field resonant frequency at once. In this paper, we evaluated material characteristics such as resonant frequency, nonlinear propagation characteristic through the development of Laser-Based Resonant Ultrasound spectroscopy (Laser-RUS) System for the detection of Micro Crack in Materials.

Study on Through Paths Inside the Air Pressure Pick-Up Head for Non-Contact Gripper (비접촉식 그리퍼 적용을 위한 공기압 파지식 헤드 내부 관통로 고찰)

  • Kim, Joon-Hyun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.4
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    • pp.563-569
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    • 2012
  • In the semiconductor and display device production processes, the handling of sensitive objects needs new carrying technology. Floating carrying motion is a practical alternative solution for non-contact handling of parts and substrates. This paper presents a study of through paths inside the air pressure pick-up head to generate the floating motion. The air motion by conceptual designed paths inside the head gradually develops positive pressure and vacuum between narrow objects. Positive pressure occurs through the head tip before discharging outside of the head. Negative pressure is developed by evacuating the inside head bottom as result of the radial flow connecting the vertical through-holes. The numerical analysis was done to figure out the stable levitation caused by the two acting forces between surfaces. In comparing with the standard case that the levitation gap gets 0.7-0.9 mm, it confirms the suggested head characteristics to show floating capacity in accordance with the head size, number of through-hole, and locations of through-hole in succession of conceptual design for a prototype.

Experimental Study for Defects Inspection of CFRP Using Laser-Generated Ultrasound

  • Lee, Joon-Hyun;Park, Won-Su;Byun, Joon-Hyung
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.41-45
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    • 2006
  • The fabrication process of fiber placement system of carbon fiber reinforced plastic (CFRP) requires real time process control and reliable inspection to ensure quality by preventing defects such as delamination and void. Therefore, novel non-contact inspection technique is required during the non-destructive evaluation in a fiber placement system. For the inspection of delamination in CFRP, various methods to receive laser-generated ultrasound were applied by using piezoelectric transducer, air-coupled transducer, wavelet transform and scanning laser ultrasonic technique. Laser-generated ultrasound was received with a conventional piezoelectric sensor in contacting manner. Then signal characteristics due to defects were analyzed to find a factor for detecting defects. Air-coupled transducer was used for reception of laser-generated guided wave using linear slit array in order to generate high frequency guided wave. And line scan technique was used to confirm the capability of on-line application. The high frequency component of laser-generated guided wave received with piezoelectric sensor disappeared after propagating through delamination region. Nevertheless, it was failed to receive high frequency guided wave in using air-coupled transducer. The first peak of the frequency spectrum under 100kHz in the delamination region is higher than in the sound region. By using this feature, the line scanned frequency data were acquired in fully non-contact generation and reception of ultrasound. This method was proved as useful technique for detecting delamination in CFRP.

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