• 제목/요약/키워드: Wave Shaping

검색결과 58건 처리시간 0.026초

Continuous rotary system과 single file system의 만곡 근관 형태 유지능에 대한 비교 연구 (Comparative Study on the Ability of Instruments to Maintain Original Canal Curvature of Continuous rotary System and Single File System)

  • 박상희;김덕중;송용범;이혜윤;김형선;이광원;유미경
    • 구강회복응용과학지
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    • 제28권4호
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    • pp.371-383
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    • 2012
  • 성공적인 근관치료를 위하여 원래 근관 형태를 따르는 근관 성형 과정이 중요하다. 그러나 대부분의 근관은 만곡되어 있고, 근관 성형 기구는 직선의 금속을 기본으로 만들어지기 때문에 근관 성형 후 만곡 근관이 원래 근관 형태를 벗어나는 오류가 나타날 수 있다. 이런 오류들로 인하여 근관 치료가 실패할 수 있으므로 근관 성형시 원래 만곡형태를 유지할 수 있는 다양한 기술과 방법들이 소개되고 있다. 본 연구의 목적은 만곡 근관 형태의 레진 모형을 이용하여 기구의 형태와 사용방법이 다른 세 가지 Ni-Ti 파일을 사용하여 Ni-Ti 파일 종류에 따른 만곡 근관에 대한 성형 후 형태 유지능을 비교하는 것이다. 직경과 경사도가 ISO 15, 0.02인 30개의 레진모형을 사용하였다. 그룹 1은 Profile을 이용하여 #20/.06까지 근관 성형하였고, 그룹 2는 Mtwo를 이용하여 #35/.04까지 근관 성형하였으며, 그룹 3은 PathFile을 이용하여 glide path를 만들어준 다음 WaveOne 파일 중 Primary을 사용하여 근관 성형하였다. 기구 사용 전과 후의 레진모형을 스캔하여 디지털 이미지로 만들었다. 각 이미지를 중첩시킨 다음 Matlab r2010b 소프트웨어를 이용하여 곡률반경의 비(CRr)를 계산하였다. 이를 바탕으로 Ni-Ti file 간 성형 후 형태 유지능을 비교하기 위하여 1-way ANOVA를 이용하여 세 그룹의 CRr의 차이에 대한 유의성 검정을 시행하였다.(P<.05) 또한 continuous rotary system과 single file system간의 형태 유지능을 비교하기 위하여 independent t-test를 이용하였다.(P<.05) 곡률반경의 비(CRr)를 이용하여 Ni-Ti 파일 종류에 따른 만곡 근관의 형태 유지능을 비교한 결과 Ni-Ti file 간에는 통계적으로 유의한 차이가 있었다.(P<0.05) ProFile과 WaveOne은 Mtwo에 비해서 만곡 근관에서의 형태 유지능이 우수하게 나타났다.Ni-Ti 기구 사용 방법에 따른 만곡 근관 형태 유지능을 비교한 결과 continuous rotary system과 single file system 간에는 통계적으로 유의한 차이를 보이지 않았다.(P>0.05) 본 연구결과에 따르면, ProFile과 WaveOne은 Mtwo에 비하여 만곡 근관에서의 형태 유지능이 통계적으로 유의하게 높게 나타났으므로, ProFile과 WaveOne이 만곡근관에 대한 형태 유지능이 우수하다고 할 수 있다. 만곡근관에서의 형태 유지능에 있어서 continuous rotary system과 single file system은 만곡근관에서의 형태 유지능에 차이가 없다.

A Study on the Art Management and Cultural Activities in China from the K-Wave Case

  • Jia Ning LI;Su SHUAI;Zhang FAN
    • 한류연구
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    • 제2권1호
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    • pp.27-31
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    • 2023
  • The purpose of this paper is to study the relationship between Art management and Cultural activities in China from the K-wave case. Research design, data, and methodology: This study used the method of the cases study survey, with the K-wave case in as the survey objects, 3 valid survey sample case were collected in this paper. Results: The two dimensions of art management and cultural activities differently influences from the K-wave, and the influence of availability on customer satisfaction is not significant. Conclusion: The results of this study will provide useful reference for the Art management and Cultural activities in China from the K-wave case. And improve the development of art management and cultural activities in China by improving the K-wave of service quality. Art management can shape urban commercial space in a beneficial way, create a good consumption atmosphere, and enhance the attractiveness and competitiveness of the city. The introduction of art elements into urban commercial space can create a strong cultural atmosphere, so that the city presents a smart look. Art management has a positive impact on K-Wave production and operation activities, which can promote the shaping of art commercial space, the promotion of urban cultural atmosphere.

생체 기에 대한 피동공명적인 연구 (Study on the wave resonance-stimultion and receptionfor the BIO-KI)

  • 류경호;김경철;이용태
    • 동의생리병리학회지
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    • 제17권2호
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    • pp.263-274
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    • 2003
  • The present condition of study on the wave-resonance for the bio-KI is observed. And the probroms of reception attendent on the stimulation of wave is observed centering around the sensory organ. The results is as follows: In the wave-resonant stand point, the tendency of studying on KI is showed in the several field all over the world. Because it is originated radionics, the wave-resonant tools of MRA insistenting minute-magnetism-resonance-apparatus need the more severe data in the side of electric circuit. The wave resonance apparatus according to the frequency occurance transmits low-frequency's vibration ratio to the electric stimulating aspect. The wave-water is considered on the application of wave-resonance transcription on the water, and needs the comprehension of torsion-field level. The wave-stimulation of the bio-KI and the reception of the sensory-organ is observed the connection of the sensory-organ and it's corresponding wave. The informations recorded in the wave are distinguished patternly. And the several shaping waves transmit the informations each other through the resonnance. The wave theory is explained the LEE(理) as the wave-pattern and the KI(氣) as the revelation of the patterned-wave in the LEE-KI theory(理氣論), moreover the SHIN(神) as the information of the wave-pattern and the KI as the energy of the wave and the JEUNG(精) as the material of the wave in the JEUNG-KI-SHIN theory(精氣神論). In this point, the study on the wave-resonance of bio-KI is thought that it is significantly in the study method for oriental medicine. The sum of the wave makes the moving body and forms the universe. It means that the several wave patterns gather and form new field. The pattern is a kind of the information and the information is not materially. The information of wave-pattern is the arrangement and the combination of the material source.

항공기용 전파흡수 구조 연구 (A Study on Radar Absorbing Structure for Aircraft)

  • 한원재;장병욱;박정선
    • 항공우주시스템공학회지
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    • 제4권3호
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    • pp.24-28
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    • 2010
  • The purpose of this study is to define available microwave absorbing structure for aircraft from in the X-band(8.2~12.4GHz) frequencies. The electromagnetic wave absorption or shielding techniques is an important issue not only for military purpose but also for commercial purposes. Aircraft Radar Absorbing Structure(RAS) is absorbed or scattered propagation waves from the enemy radar. There are absorbing technologies at shaping design techniques and using Radar Absorbing Materials(RAM). RAM is more important because shaping design can't include perfect radar absorbing performance. In this study, based on material properties was introduced RAM and to analyze the each characteristics. Finally, we comparison appropriate RAM for aircraft.

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RF 스텔스 효과를 위한 밀리미터 RAM 개발 (Development of RAM in Millimeter Wave Range for RF Stealth)

  • 최창묵;임봉택;고광섭
    • 한국정보통신학회논문지
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    • 제13권6호
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    • pp.1241-1246
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    • 2009
  • 본 논문은 상대방으로부터 탐지를 최소화시키는 스텔스 기술을 분석하고, 대부분의 레이더 반사 단면적 감소는 형상화로부터 기인되며, 특별한 부위에는 RAM을 이용하여 최소화 시키는 것을 확인하였다. 따라서 RF 스텔스를 위한 밀리미터파 대역의 레이더 반사 단면적을 최소화시키는 측면에서 94 GHz에서 전파흡수량 17 dB로 98 %를 흡수하는 RAM을 설계 및 제작하였다. 결과적으로 개발된 RAM을 플랫폼에 적용시 상대방으로부터 레이더 탐지거리를 62 % 축소시키는 효과를 얻을 수 있다.

RF 스텔스를 위한 밀리미터 RAM 개발 (Development of RAM in Millimeter Wave Range for RF Stealth)

  • 최창묵;임봉택;고광섭
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2009년도 춘계학술대회
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    • pp.555-558
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    • 2009
  • 본 논문은 상대방으로부터 탐지를 최소화시키는 스텔스 기술을 분석하고, 대부분의 레이더 반사 단면적 감소는 형상화로부터 기인되며, 특별한 부위에는 RAM을 이용하여 최소화 시키는 것을 확인하였다. 따라서 RF 스텔스를 위한 밀리미터파 대역의 레이더 반사 단면적을 최소화시키는 측면에서 94 GHz에서 전파흡수량 17 dB로 98 %를 흡수하는 RAM을 설계 및 제작하였다. 결과적으로 개발된 RAM을 플랫폼에 적용시 상대방으로부터 레이더 탐지거리를 62 % 축소시키는 효과를 얻을 수 있다.

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π/2 Pulse Shaping via Inverse Scattering of Central Potentials

  • 이창재
    • Bulletin of the Korean Chemical Society
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    • 제17권2호
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    • pp.188-192
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    • 1996
  • It is shown that the inversion of the undamped Bloch equation for an amplitude-modulated broadband π/2 pulse can be precisely treated as an inverse scattering problem for a Schrodinger equation on the positive semiaxis. The pulse envelope is closely related to the central potential and asymptotically the wave function takes the form of a regular solution of the radial Schrodinger equation for s-wave scattering. An integral equation, which allows the calculation of the pulse amplitude (the potential) from the phase shift of the asymptotic solution, is derived. An exact analytical inversion of the integral equation shows that the detuning-independent π/2 pulse amplitude is given by a delta function. The equation also provides a means to calculate numerically approximate π/2 pulses for broadband excitation.

Pulse Shaper를 이용한 SHPB 실험 응력파 제어 효과의 해석 및 실험적 검증 (Numerical and Experimental Verification of Stress Wave Control Effect in SHPB Experiment using Pulse Shaper)

  • 김용희;우민아;강범수;김정
    • 소성∙가공
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    • 제26권5호
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    • pp.314-322
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    • 2017
  • In the high-speed forming analysis, dynamic material properties considering a high strain rate are required. The split Hopkinson pressure bar (SHPB) experiment was performed for measuring dynamic material properties under high strain rate. The pulse shaping method was used to improve the accuracy of the SHPB experiment. A pulse shaper attached to the front of the incident bar was used for specimen dynamic stress equilibrium through stress wave control. Numerical analysis and SHPB test were performed to verify whether the pulse shaper affects the dynamic stress equilibrium in copper and Al6061 specimens. The results of SHPB test and numerical analysis show that the pulse shaper contributes to the dynamic stress equilibrium. Based on the improved stress equilibrium using a pulse shaper, the flow stress curves for copper and Al6061 materials were obtained at strain rates of 1344.4/sec and 1291.6/sec, respectively.

음향 및 진동장의 형상을 제어하는 다양한 방법 (A Unified Theory of Spatial Sound and Vibration Control with Multiple Sources)

  • 김양한;최정우
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.126-132
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    • 2006
  • In this paper, we aim to control the sound and vibration spatially, so that a desired physical variable is enhanced within a zone we select. This is somewhat analogous to have manipulators that can draw wave shape in any place we want. Brightness and contrast control have shown that such a manipulation is possible by controlling multiple sources[J.-W. Choi and Y.-H. Kim, J. Acoust. Soc. Am. 111(4), 2002]. In particular, the acoustic brightness control seeks a way to increase loudness of sound over a chosen area, and the contrast control aims to enhance loudness difference between two neighboring regions. This enables us to manipulate spatial distribution of sound by making two different kinds of zone ? the bright and dark zone- at the same time. The primary focus of this study is to unit the theoretical formulation of the brightness and contrast control and to find a link between these methods, as well as its relation to other conventional techniques. It is also shown that we can generate various shape of wave field by transforming the domain we consider.

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A Novel Approach for Controlling Process Uniformity with a Large Area VHF Source for Solar Applications

  • Tanaka, T.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.146-147
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    • 2011
  • Processing a large area substrate for liquid crystal display (LCD) or solar panel applications in a capacitively coupled plasma (CCP) reactor is becoming increasingly challenging because of the size of the substrate size is no longer negligible compared to the wavelength of the applied radio frequency (RF) power. The situation is even worse when the driving frequency is increased to the Very High Frequency (VHF) range. When the substrate size is still smaller than 1/8 of the wavelength, one can obtain reasonably uniform process results by utilizing with methods such as tailoring the precursor gas distribution by adjustingthrough shower head hole distribution or hole size modification, locally adjusting the distance between the substrate and the electrode, and shaping shower head holes to modulate the hollow cathode effect modifying theand plasma density distribution by shaping shower head holes to adjust the follow cathode effect. At higher frequencies, such as 40 MHz for Gen 8.5 (2.2 m${\times}$2.6 m substrate), these methods are not effective, because the substrate is large enough that first node of the standing wave appears within the substrate. In such a case, the plasma discharge cannot be sustained at the node and results in an extremely non-uniform process. At Applied Materials, we have studied several methods of modifying the standing wave pattern to adjusting improve process non-uniformity for a Gen 8.5 size CCP reactor operating in the VHF range. First, we used magnetic materials (ferrite) to modify wave propagation. We placed ferrite blocks along two opposing edges of the powered electrode. This changes the boundary condition for electro-magnetic waves, and as a result, the standing wave pattern is significantly stretched towards the ferrite lined edges. In conjunction with a phase modulation technique, we have seen improvement in process uniformity. Another method involves feeding 40 MHz from four feed points near the four corners of the electrode. The phase between each feed points are dynamically adjusted to modify the resulting interference pattern, which in turn modulate the plasma distribution in time and affect the process uniformity. We achieved process uniformity of <20% with this method. A third method involves using two frequencies. In this case 40 MHz is used in a supplementary manner to improve the performance of 13 MHz process. Even at 13 MHz, the RF electric field falls off around the corners and edges on a Gen 8.5 substrate. Although, the conventional methods mentioned above improve the uniformity, they have limitations, and they cannot compensate especially as the applied power is increased, which causes the wavelength becomes shorter. 40 MHz is used to overcome such limitations. 13 MHz is applied at the center, and 40 MHz at the four corners. By modulating the interference between the signals from the four feed points, we found that 40 MHz power is preferentially channeled towards the edges and corners. We will discuss an innovative method of controlling 40 MHz to achieve this effect.

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