• Title/Summary/Keyword: Air Tool

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Analysis and Dynamic Modeling of a High-speed Tube Expander (고속 Tube Expander의 동적 모델링 및 해석)

  • 김재량;정원지;김수태;최욱환
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.10a
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    • pp.401-411
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    • 2003
  • Tube expanding process is for combining a heat-sink plate with hair-pins (Cu-tube) through plastic deformation. The two parts, i. e. , heat-sink plate and hair-pins are they components of a heat-exchanger for an air conditioner. This paper presents the analysis and dynamic modeling of a high-speed tube expander which integrates transfer of parts, fixing of parts, and tube expanding into one process. The 3-dimensional modeling of all the parts for the tube-expander was constructed using CATIA$\circledR$. then the CATIA$\circledR$ models are transferred into visuaINastran$\circledR$ to execute the 3-dimensional animation for checking prescribed cycle-time. The technique presented in this paper has been shown to be effective as a priori tool for verifying the design of a high-speed tube expander.

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A Study on the characteristic of micro deep hole drilling (마이크로 Deep hole 가공 특성에 관한 연구)

  • 김동우;조명우;이응숙;강재훈;민승기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.1064-1067
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    • 2001
  • Micro drilling is used in the production of fuel injection nozzle, watch, camera, air bearing and pinted circuit boards(PCB) are demanded for high precision. Recently industries of precision production require more small hole, high aspect ratio and high speed working for micro deep hole drilling. But the undesirable characteristics of micro drilling is the small signal to noise ratios, wandering motion of drill, high aspect ratio and the increase of cutting force as cutting depth increase. So in this paper to obtain the optimization of cutting condition a study on the characteristics of micro deep hole drilling used Tool dynamometer is proposed.

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Optimum Machining Condition of Die Steel In The Oil-mist Condition (오일미스트 조건에서의 금형강의 최적절삭조건)

  • Kim Sang-Min;Kim Joon-Hyun;Kim Joo-Hyun
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.15 no.2
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    • pp.59-65
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    • 2006
  • The purposes of using cutting fluid during cutting have been cooling, lubricating, chip washing and anti-corroding. However, the present manufacturing industry restricts the use of cutting fluid because cutting fluid contains poisonous substances which are harmful to the human body. Therefore environmentally conscious machining and technology have more important position in machining process because cutting fluids have significant influence on the environment in milling process. In this study, environmentally conscious machining can be obtained by the way of selecting the optimum machinig conditon using the design of experiment. Cutting using oil-mist showed better cutting characteristics than dry, air and fluid cutting with respect to by cutting force, tool wear and surface roughness. Also, the optimum machining condition for cutting using oil-mist could be selected through Taguchi method.

A Study on the Microscopic Precision of Machined Surface according to Variation of Machining Environments in High Speed Endmilling (고속 엔드밀가공에서 가공환경 변화에 따른 가공면의 미시적 정밀도에 관한 연구)

  • Kwon, Dong-Hee;Lee, Jong-Hwan;Hwang, In-Ok;Kang, Myung-Chang;Kim, Jeong-Suk
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.15 no.6
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    • pp.50-57
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    • 2006
  • The investigation of microscopic precision in high speed endmilling is necessary for machinability evaluation, and the environmentally conscious machining technology have more important position in recent machining process. The microscopic precision of workpiece is influenced by machining environments variation as cutting fluid type and lubricant method. In this study, the cutting forces according to variation of cooling and lubrication are investigated by specially designed tool dynamometer. And the surface roughness, micro hardness and residual stress are evaluated according to machining environment. The characteristics of damaged layer in environmentally conscious machining and conventional machining using cutting fluid are compared experimentally.

Development of the Avionics System Development Rig (항공전자시스템 개발치구 개발)

  • Park, Deok-Bae;Hwang, Sang-Hyun;Lee, Sung-Soo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.7
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    • pp.106-113
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    • 2005
  • ASDR(Avionic System Development Rig) is used as a development tool during the design and development of the ASC/OFP and then can be used as a maintenance tool after developing them for a military aircraft. This paper describes the overall structure and the important features of KO-1 ASDR, especially about the dynamic simultion of inertial and air data sensors.

A New Moving-magnet Type Linear Actuator utilizing Flux Concentration Permanent Magnet Arrangement

  • Goto, Akira;Okamoto, Takuya;Ikariga, Atsushi;Todaka, Takashi;Enokizono, Masato
    • Journal of Electrical Engineering and Technology
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    • v.7 no.3
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    • pp.342-348
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    • 2012
  • This paper presents a moving-magnet type linear actuator designed by using flux concentration type permanent magnet arrangement, which can generate higher magnetic flux density in air-gap. In this construction, detent force which is induced by both slot-effect and end-effect becomes larger due to strong attractive forces. To reduce cogging force we have employed a modular mover structure of two magnetic pole sections connected with a center yoke. The improved motor performance is demonstrated with the prototype machine.

The study of development of quantitative risk assesment program for the road tunnel (도로터널 위험도 평가프로그램 개발에 관한 연구(I))

  • Yoo, Ji-Oh;Shin, Hyun-Jun;Rie, Dong-Ho
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.460-467
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    • 2006
  • Some large accidents in tunnels in recent years, such as Mont Blanc, Gotthard and Tauern tunnels, have lead to an increasing attention for tunnel safety and necessity of tool for quantitative risk assesment of road tunnel. And the purpose of this study is to develop the quantitative risk assesment tool for the application of road tunnel. The objectives of this paper are as follows : (1) analyze of traffic accident rates in tunnel, (2) make out scenario for fire accidents, (3) develop the evacuation model and FED calculation model, (4) Present the results from quantitative risk assesment for the model tunnel according with the fire heat release rates and distances of cross passage.

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Determination of Egg Freshness and Internal Quality Measurement Using Image Analysis (계란의 신선도 결정과 영상분석을 이용한 내부품질 측정)

  • Kim, Hyeon-T.;Ko, Han-J.;Kim, Ki-Y.;Kato, K.;Kita, Y.;Nishizu, T.
    • Journal of Biosystems Engineering
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    • v.32 no.3
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    • pp.166-172
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    • 2007
  • Egg quality indices are related with freshness, size of air chamber, loss of weight, and viscosity of the yolk and the protein. However, since the described quality parameters require measured in a destructive way, it is not suitable to inspect the egg quality with complete enumeration. Therefore, this study was performed to investigate the potential of image analysis method for evaluation of internal egg quality. Samples of 90 fresh eggs were collected immediately after laying and stored up to 24 days. Five eggs were randomly drawn from each storage condition (packing vs unpacking) at a regular interval and loss of weight, specific gravity and size of air chamber were measured. The image analysis for nondestructive measurement of size of air chamber was also studied. Results showed that the egg weight and gravity gradually decreased with increasing of storage days, while the size of air chamber linear increased caused by evaporation of water through the shell. A relationship a between conventional method and the image analysis method for measuring the size of air chamber was developed with the correlation coefficient of 0.928. The new finding implied that image analysis might provide a useful nondestructive tool to assess internal egg quality.

Quantitative Assessment on Contributions of Foreign NOx and VOC Emission to Ozone Concentrations over Gwangyang Bay with CMAQ-HDDM Simulations (CMAQ-HDDM을 이용한 광양만 오존 농도의 국외 기여도 분석)

  • Bae, Changhan;Kim, Byeong-Uk;Kim, Hyun Cheol;Kim, Soontae
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.5
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    • pp.708-726
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    • 2018
  • In this study, we examined the contribution of nitrogen oxides and volatile organic compounds emitted from China and Japan to ozone concentrations over Gwangyang-bay, South Korea. We used a chemical transport model, Community Multi-scale Air Quality model, and its instrumented sensitivity tool, High-order Decoupled Direct Method. Intercontinental Chemical Transport Experiment-Phase B 2006 for East Asia and Clean Air Policy Support System 2007 emissions inventories for South Korea were used for the ozone simulation. During the study period, May 2007, the modeled maximum daily 8-hr average ozone concentration among seven air quality monitors in Gwangyang-bay was 68.8 ppb. The contribution of $NO_x$ emissions from China was 19.5 ppb (28%). The highest modeled ozone concentrations and Chinese contributions appeared when air parcels were originated from Shanghai area. The observed 8-hr average ozone concentrations in Gwangyang Bay exceeded the national ambient air quality standard (60 ppb) 203 times by daytime and 56 times by nighttime during the period. It was noticed that many exeedances happened when contribution of Chinese emissions to ozone concentrations over the area increased. Sensitivity analysis shows that a reduction in Chinese $NO_x$ and VOC emissions by 15% could lessen the total exceedance hours by 24%. This result indicates that high ozone concentrations over Gwangyang-bay are strongly enhanced by Chinese emissions.

Analysis of Microbial Community in the TPH-Contaminated Groundwater for Air Sparging using Terminal-Restriction Fragment Length Polymorphism (유류오염대수층 공기분사공정상의 미생물 제한효소다형성법 적용 평가)

  • Lee, Jun-Ho;Lee, Sang-Hoon;Cho, Jae-Chang;Park, Kap-Song
    • Journal of Korean Society on Water Environment
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    • v.22 no.4
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    • pp.590-598
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    • 2006
  • In-situ Air sparging (IAS) is a groundwater remediation technique, in which organic contaminants volatilize into air form the saturated to vadose zone. This study was carried out to evaluate the effect of sludge and soil microbial community structure on air sparging of Total Petroleum Hydrocarbons (TPH) contaminated groundwater soils. In the laboratory, diesel (10,000 mg TPH/kg) contaminated saturated soil. The Air was injected in intermittent (Q=1500 mL/min, 10 minute injection and 10 minute idle) modes. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for experiment with sludge soil samples that were closely related to Agrococcus, Flavobacterium, Thermoanaerobacter, Flexibacter and Shewanella, etc, in the clone library. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil the fate of microorganisms in natural microbial community.