• 제목/요약/키워드: Wave process

검색결과 1,591건 처리시간 0.027초

A Case Study of Six Sigma Project for Improving method of measuring pulse wave (6시그마 기법을 통한 안정된 맥파측정 프로세스 설계)

  • Lee, Jeon;Lee, Yu-Jung;Lee, Hae-Jung;Choi, Eun-Ji;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • 제12권2호통권17호
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    • pp.85-92
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    • 2006
  • Pulse is one of the basic diagnostic information of TKM(Traditional Korean Medicine). To quantify and standardize pulse diagnosis, we had collected an amount of clinical data from May 2005 by using newly developed pulse analyzer. But there were many noises in pulse wave according to measuring method, environment, operator and condition of patient. So some data can’t be included for analyzing diagnosis. To reduce noises from measuring pulse and to collect reliable pulse wave data, we made the process map of measuring method and applied six sigma project. With this we can improved the method of measuring pulse wave in collecting clinical data. The project follows a disciplined process of five macro phases: define, measure, analyze, improve and control (DMAIC). A process map and C-E diagram are used to identify process input and output variables. The major input variables are selected by using C&E matrix, and process map is developed by analyzing input variables. And the optimum process conditions are going to be controled to avoid in increasing loss of collecting pulse wave data.

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The Comparison of the Bead Size Effect on the Two Wave Patterns Induced in One Reaction System

  • Heo, Do Seong;Kim, Min Seok;Jo, Sang Jun
    • Bulletin of the Korean Chemical Society
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    • 제22권8호
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    • pp.867-871
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    • 2001
  • We have studied the characteristic wave propagation in 1,4-CHD-Bromate-Ferroin reaction system and we have examined the bead size effect on the wave propagation of the system by adopting a half-divided Petri dish which is separated into two parts by the size of cation-exchange resin. It has been done to understand the reaction process inducing the characteristic wave behavior in the system. The characteristic wave behavior of the system is in the spontaneous induction of a revival wave with a long time lag. We have obtained a result that the revival wave is not affected by the size of catalyst-doped beads while the initially induced wave is influenced by the size of beads. It means that the two waves are induced by different reaction processes each other and the revival wave is induced by an uncatalyzed reaction process.

Process Optimization for the Laser Cutting of Cold Rolled STS Sheet (냉연 스테인리스강판의 레이저 절단 특성)

  • 이기호;김기철
    • Journal of Welding and Joining
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    • 제14권5호
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    • pp.59-68
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    • 1996
  • This study was aimed to characterize the laser cutting process for the cold rolled stainless steel sheet. The principal process parameters of the cutting process were applied to both the continuous wave form and the pulsed wave form for the laser output mode. The laser-oxygen cutting process and the laser-nitrogen cutting process were also considered to characterize the quality and efficiency of the cutting process. The laser-oxygen cutting process revealed the better productivity than the laser-nitrogen cutting process, since the laser energy and the exothermic oxidation energy exerted on the laser-oxygen cutting process simultaneously during the entire cutting process. However, the straightness of the cutting section, which was considered as the most important factors, was inferior to that of the laser-nitrogen cutting process due to the formation of chromum oxide on the cutting surface. Frequency and duration of the pulsed wave form act as the main factors for the better quality, When the frequency increased from 100 Hz to 200 Hz and the duty increased from 20% to 40%, the quality factors such as the height of dross and the surface roughness were improved remarkably. The increase in the frequency from 200 Hz to 300 Hz, on the other hand, revealed the less effective in the cutting quality.

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Investigation of acoustic monitoring on laser shock cleaning process (레이저 충격파 클리닝 공정에서 음향 모니터링에 관한 연구)

  • 김태훈;이종명;조성호;김도훈
    • Laser Solutions
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    • 제6권2호
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    • pp.27-33
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    • 2003
  • A laser shock cleaning technology is a new dry cleaning methodology for the effective removal of small particles from the surface. This technique uses a plasma shock wave produced by a breakdown of air due to an intense laser pulse. In order to optimize the laser shock cleaning process, it needs to evaluate the cleaning performance quantitatively by using a monitoring technique. In this paper, an acoustic monitoring technique was attempted to investigate the laser shock cleaning process with an aim to optimize the cleaning process. A wide-band microphone with high sensitivity was utilized to detect acoustic signals during the cleaning process. It was found that the intensity of the shock wave was strongly dependent on the power density of laser beam and the gas species at the laser beam focus. As a power density was larger, the shock wave became stronger. It was also seen that the shock wave became stronger in the case of Ar gas compared with air and N$_2$ gas.

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Experimental study on the tension of cables and motion of tunnel element for an immersed tunnel element under wind, current and wave

  • Wu, Hao;Rheem, Chang-Kyu;Chen, Wei;Xu, Shuangxi;Wu, Weiguo
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제13권1호
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    • pp.889-901
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    • 2021
  • The tension of cables and motion response significantly affect safety of an immersed tunnel element in the immersion process. To investigate those, a hydrodynamic scale-model test was carried out and the model experiments was conducted under wind, current and wave loads simultaneously. The immersion standby (the process that the position of the immersed tunnel element should be located before the immersion process) and immersion process conditions have been conducted and illustrated. At the immersion standby conditions, the maximum force of the cables and motion is much larger at the side of incoming wind, wave and current, the maximum force of Element-6 (6 cables directly tie on the element) is larger than for Pontoon-8 (8 cables tie on pontoon of the element), and the flexible connection can reduce the maximum force of the mooring cables and motion of element (i.e. sway is expecting to decrease approximate 40%). The maximum force of the mooring cables increases with the increase of current speed, wave height, and water depth. The motion of immersed tunnel element increases with increase of wave height and water depth, and the current speed had little effect on it. At the immersion process condition, the maximum force of the cables decrease with the increase of immersion depth, and dramatically increase with the increase of wave height (i.e. the tension of cable F4 of pontoons at wave height of 1.5 m (83.3t) is approximately four times that at wave height of 0.8 m). The current speed has no much effect on the maximum force of the cables. The weight has little effect on the maximum force of the mooring cables, and the maximum force of hoisting cables increase with the increase of weight. The maximum value of six-freedom motion amplitude of the immersed tunnel element decreases with the increase of immersion depth, increase with the increase of current speed and wave height (i.e. the roll motion at wave height of 1.5 m is two times that at wave height of 0.8 m). The weight has little effect on the maximum motion amplitude of the immersed tunnel element. The results are significant for the immersion safety of element in engineering practical construction process.

Ocean Engineering Basic Test for 5MW Offshore Wind Turbine Sub-structure Jack-up Platform (5MW급 해상풍력 Sub-structure Jack-up Platform 수조모형시험)

  • Jeon, Jung-Do;Jeon, Eon-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • 제12권1호
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    • pp.15-21
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    • 2013
  • The safety and stability of 5MW class offshore wind turbine Jack-up platform was investigated through ocean basin experiment. For simulating the environmental condition of yellow sea in the South Korea, diverse waves, winds and currents were performed based on Froude's number. Regular wave and irregular wave based on Froude's number were applied to the wind turbine structure. In experiments, the height and period of regular wave type were scaled down as the 1:50 ratio of real wave condition. Irregular wave type was simulated with TMA(Texel Storm, Marsen and Arsloe)spectrum. The vertical reaction force, resonance period and wave pressure applied to multi-supporters of wind offshore structure were measured experimentally. Finally, the results showed that the capsizing situation of the offshore structure was generated by the severe environmental condition.

Application Advanced One-Sided Stress Wave Velocity Measurement in Concrete (콘크리트에서의 One-Sided 응력파 속도 측정 기법의 적용에 관한 연구)

  • ;;J.S.Popovice;J.D.Achenbach
    • Proceedings of the Korea Concrete Institute Conference
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.544-550
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    • 1997
  • In this study, the advanced on-sided stress wave velocity measurement method was applied to investigate the effects of composition, age and moisture content in concrete. Two concrete specimens that have different composition were used to figure out the change of the Longitudinal and Surface wave velocity due to different composition. The other concrete specimen was cast and the Longitudinal and Surface wave velocity was monitored during curing process. After 28-day old, the effect of moisture content in the concrete specimen to the stress wave velocity is presented in this paper during the time period 43-74 days after casting. For drying process. an aggregate drying oven was used. A conventional ultrasonic through transmission method was used to compare with the results determined by the one-sided method.

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Hair Damage and Wave Shape according to Dyeing, Bleaching, Permanent Wave Treatment (염.탈색 및 펌 처리에 따른 모발의 손상과 웨이브 형상)

  • Kweon, Soo-Ae;Roh, Joung-Ae;Park, Yong
    • Korean Journal of Human Ecology
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    • 제15권6호
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    • pp.1083-1089
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    • 2006
  • In this paper, the damage of hair and wave shape in process of the dyeing, bleaching, and permanent hair wave are simulated. The virgin hair that do not process the dyeing, bleaching, and permanent hair wave becomes stable in the scale type. On the other hand, the hair that deals with the dyeing, bleaching, and permanent hair wave is heavily damaged in the scale type. It is observed that the higher pH is decided, the higher the hair is damaged because the scale damage in the bleaching hair is more heavily damaged than the dyeing hair. In case of executing the permanent hair wave, the processing of the plaine rinsing becomes less in the scale damage of the hair and better in the wave form. Therefore, it is found that the processing of the plaine rinsing to improve the wave form and to prevent the hair damage is needed.

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Evolution of Surface Profiles of Breaking Waves Generated by Directional Wave Focusing (다방향 파랑집중에 의한 쇄파의 파형특성 연구)

  • Hong Keyyong;Choi Hak-Sun
    • Journal of the Korean Society for Marine Environment & Energy
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    • 제5권1호
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    • pp.11-18
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    • 2002
  • Directional breaking waves are generated by the component wave focusing both in direction and frequency based on constant wave steepness and constant wave amplitude spectrum models. The generated breaking waves are classified in the incipient, single and multi breaking waves. The characteristics of directional breaking waves are investigated in terms of surface profile parameters of wave crest steepness and asymmetry. The evolution of breaking wave characteristics is analyzed in a view of focusing efficiency. It shows that the front steepness and vertical asymmetry play an important role in breaking process, while the crest rear steepness and horizontal asymmetry are nearly constant during the process. The superposition of directional components greatly enhances the focusing efficiency and it suggests that characteristics of directional breaking waves may significantly different from uni-directional ones.

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Dielectric/Magnetic Nanowires Synthesized by the Electrospinning Method for Use as High Frequency Electromagnetic Wave Absorber

  • Jwa, Yong-Ho
    • Proceedings of the Materials Research Society of Korea Conference
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    • 한국재료학회 2009년도 추계학술발표대회
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    • pp.14-14
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    • 2009
  • High frequency electromagnetic(EM) waves are increasingly being applied in industries because of saturationat lower frequency bands as a result of huge demand. However, electromagneticinterference (EMI) has become a serious problem, and as a result, highfrequency EM absorbers are now being extensively studied. Also, recentdevelopments in absorber technology have focused on producing absorbers thatare thin, flexible, and strong. Hence, one-dimension ferrous nano-materials area potential research field, because of their interesting electronic andmagnetic properties. Commercially, EM wave absorbing products are made ofcomposites, which blend the insulating polymer with magnetic fillers. Inparticular, the shape of the magnetic fillers, such flaky, acicular, or fibrousmagnetic metal particles, rather than spherical, is essential for synthesizingthin and lightweight EM wave absorbers with higher permeability. High aspectratio materials exhibit a higher permeability value and therefore betterabsorption of the EM wave, because of electromagnetic anisotropy. Nanowires areusually fabricated by drawing, template synthesis, phase separation, selfassembly, and electrospinning with a thermal treatment and reduction process.Producing nanowires by the electrospinning method involves a conventionalsol-gel process that is simple, unique, and cost-effective. In thispresentation, Magnetic nanowire and dielectric materials coated magneticnanowire with a high aspect ratio were successfully synthesized by theelectrospinning process with heat treatment and reduction. In addition toestimating the EM wave absorption ability of the synthesized magnetic anddielectric materials coated magnetic nanowire with a network analyzer, weinvestigated the possibility of using these nanowires as high-frequency EM waveabsorbers. Furthermore, a wide variety of topics will be discussed such as thetransparent conducting nanowire and semiconducting nanowire/tube with theelectrospinning process.

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