• 제목/요약/키워드: Interrupted wave

Search Result 12, Processing Time 0.03 seconds

Effect of Electroacupuncture Complex Therapy on Peripheral Facial Paralysis According to the Wave Forms (파형에 따른 말초성 안면신경마비의 전침 복합 치료 효과)

  • Choi, Chul-Hoon;Song, Ho-Sueb
    • Journal of Acupuncture Research
    • /
    • v.27 no.5
    • /
    • pp.43-50
    • /
    • 2010
  • Objectives : This study was to compare the effect of electroacupuncture therapy on peripheral facial paralysis according to the wave forms. Methods : We investigated 56 cases of inpatients with Peripheral Facial Paralysis, and divided them into two groups, One group was treated by electroacupuncture on interrupted wave, and the other was treated by electroacupuncture on dense-dispersed wave. We evaluated the effect of electroacupuncture in each group by using Gross Grading System of House-Brackmann and Yanagihara's Unweighed Grading System. Results : 1. In the interrupted wave and the dense-dispersed wave, compared with baseline, at final, Gross Grading System of House-Brackmann was significantly decreased and Yanagihara's Unweighed Grading System was significantly increased. 2. At final, Interrupted wave showed significant decrease on the Gross Grading System of House-Brackmann and significant increase on Yanagihara's Unweighed Grading System compared with dense-dispersed wave. Conclusions : These results suggested that interrupted wave should be more useful for improving symptoms related with peripheral facial paralysis than dense-dispersed wave.

Spectral Analysis Method to Eliminate Spurious in FMICW HRR Millimeter-Wave Seeker (주파수 변조 단속 지속파를 이용하는 고해상도 밀리미터파 탐색기의 스퓨리어스 제거를 위한 스펙트럼 분석 기법)

  • Yang, Hee-Seong;Chun, Joo-Hwan;Song, Sung-Chan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.23 no.1
    • /
    • pp.85-95
    • /
    • 2012
  • In this thesis, we develop a spectral analysis scheme to eliminate the spurious peaks generated in HRR Millimeterwave Seeker based on FMICW system. In contrast to FMCW system, FMICW system generates spurious peaks in the spectrum of its IF signal, caused by the periodic discontinuity of the signal. These peaks make the accuracy of the system depend on the previously estimated range if a band pass filter is utilized to eliminate them and noise floor go to high level if random interrupted sequence is utilized and in case of using staggering process, we must transmit several waveforms to obtain overlapped information. Using the spectral analysis one of the schemes such as IAA(Iterative Adaptive Approach) and SPICE(SemiParametric Iterative Covariance-based Estimation method) which were introduced recently, the spurious peaks can be eliminated effectively. In order to utilize IAA and SPICE, since we must distinguish between reliable data and unreliable data and only use reliable data, STFT(Short Time Fourier Transform) is applied to the distinguishment process.

The Prediction of Fatigue Damage for Pressure Vessel Materials using SH Ultrasonic Wave (압력용기 고온 고압부의 피로손상 예측을 위한 SH 초음파 평가 기법 개발)

  • Kang, Yong-Ho;Chung, Yong-Keun;Park, Jong-Jin;Park, Ik-Min
    • Proceedings of the KSME Conference
    • /
    • 2003.04a
    • /
    • pp.678-683
    • /
    • 2003
  • Ultrasonic method using SH(shear horizontal) wave has been developed to determine the surface damage in fatigued material. Fatigue damages based on propagation energy were analyzed by multiregression analysis and phase measurement in interrupted fatigue test specimen including CrMoV and 12Cr alloy steel. From the test results, as the fatigue damage increased the propagation time of the launched waves increased and amplitude of wavelet decreased. Also, analysis for the waveform modulation showed a reliable estimation, with confidence limit of 97% for 12Cr steel and 95% for CrMoV steel, respectively. Therefore, It is thought that SH ultrasonic wave technique can be applied to determine fatigue damage of in-service component nondestructively.

  • PDF

The Prediction of Fatigue Damage for Pressure Vessel Materials using Shear Horizontal Ultrasonic Wave (SH(shear horizontal) 초음파를 이용한 압력용기용 재료의 피로손상 예측)

  • Kang, Yong-Ho;Chung, Yong-Keun;Song, Jung-Il
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.26 no.6
    • /
    • pp.90-96
    • /
    • 2009
  • Ultrasonic method using SH(shear horizontal) wave has been developed to determine the surface damage in fatigued material. Fatigue damages based on propagation energy were analyzed by multi-regression analysis in interrupted fatigue test specimen including CrMoV and 12Cr alloy steel. From the test results, as the fatigue damage increased the propagation time of the launched waves increased and amplitude of wavelet decreased. Also, analysis for the waveform modulation showed a reliable estimation, with confidence limit of 97% for 12Cr steel and 95% for CrMoV steel, respectively. Therefore, It is thought that SH ultrasonic wave technique can be applied to determine fatigue damage of in-service component nondestructively.

Analysis of Effects of Phase Noise in Radar System (위상잡음이 레이더 시스템에 미치는 영향 분석)

  • Park, Jinsung
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.16 no.3
    • /
    • pp.373-381
    • /
    • 2013
  • In this paper, the effects of phase noise on the radar system were analyzed in terms of 3 point of view. The impact(s) on the compressed pulse waveform, the FMICW(Frequency Modulated Interrupted Continuous Wave) radar performance and the receiver sensitivity were investigated. From the investigation, it was indicated that the phase noise over 10 kHz offset frequency makes the side lobe level of compressed pulse worse. Also it was founded that the FMICW radar performance, especially at the noise level of range profile, is related to the phase noise. Finally, the investigation showed that the phase noise at local oscillator affects the receiver sensitivity.

Detection of Fault ONUs in TDM-PON Using CDMA Modulation Scheme (CDMA 변조방식을 이용한 TDM-PON의 고장 ONU 검출)

  • Choi, Byung-Chul;Park, Jae-Uk;Chung, Jun-Hoi;Park, Young-Il
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.33 no.1A
    • /
    • pp.1-6
    • /
    • 2008
  • TDM-PON has a disadvantage that entire PON system gets into trouble when only one ONU is out of order and sends optical signal constantly. This paper suggests a scheme to find the fault location. TDMA is impossible when upstream traffic is interrupted by continuous wave signal from a troubled ONU. Therefore, CDMA coding is introduced in separating fault ONUs, and detection algorithm is verified.

Sweep Nonlinearity Estimation for High Range Resolution Millimeter-Wave Seeker Using Least Squares Method (최소 자승법을 이용한 고해상도 밀리미터파 탐색기의 비선형 위상 오차의 추정)

  • Yang, Hee-Seong;Chun, Joo-Hwan;Song, Sung-Chan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.23 no.1
    • /
    • pp.56-67
    • /
    • 2012
  • In this thesis, to compensate the sweep nonlinearity occurring in the high resolution radar system using FMICW or FMCW, the method of the estimation of the nonlinearity is proposed. The nonlinear phase component caused by the nonlinear characteristic of the radar system is modelled as a linear combination of the sinusoidal functions consisting of various magnitudes and phases(systematic nonlinear phase error) and a random component(stochastic nonlinear phase error). From two IF signals that are measured respectively independently for two reference point targets lying in different distances which are known, a sparse linear equation is made and solved by least squares method to estimate the nonlinear phase component. The estimated component can be used for predistortion method to compensate the sweep nonlinearity.

Crustal Structure of the Southern Part of Korea (한국(韓國) 남부지역(南部地域)의 지각구조(地殼構造))

  • Kim, Sung Kyun;Jung, Bu Hung
    • Economic and Environmental Geology
    • /
    • v.18 no.2
    • /
    • pp.151-157
    • /
    • 1985
  • Events detected by the KIER microearthquake network operated in the Southern Part of Korea for 265 days in 1982~1984 were reviewed, and some of them were identified to be a dynamite explosion from several construction sites. The purpose of the present work is to determine the crustal structure of the Southern Korea using the time-destance data obtained from such explosion seismic records. The time·distance data can be well explained by a crustal model composed of four horizontal layers of which thickness, p and s-wave velocity ($V_p$ and $V_s$) are characterized as follows. 1st layer (surface) ; 0~2km, $V_p=5.5km/sec$, $V_s=3.3km/sec$ 2nd layer (upper crust) ; 2~15km, $V_p=6.0km/sec$, $V_s=3.5km/sec$ 3rd layer (lower crust) ; 15~29km, $V_p=6.6km/sec$, $V_s=3.7km/sec$ 4th layer (upper mantle) ; 29km~ , $V_p=7.7km/sec$, $V_s=4.3km/sec$ The relatively shallow crust·mantle boundary and low $P_n$ velocity compared with the mean values for stable intraplate region are noteworthy. Supposedely, it is responsible for the high heat flow in the South-eastern Korea or an anomalous subterranean mantle. The mean $V_p/V_s$ ratio calculated from the relation between p-wave arrival and s-p arrival times appears to be 1.735 which is nearly equivalent to the elastic medium of ${\lambda}={\mu}$. However, the ratio tends to be slightly larger with the depth. The ratio is rather high compared with that of the adjacent Japanese Island, and the fact suggests that the underlying crust and upper mantle in this region are more ductile and hence the earthquake occurrences are apt to be interrupted. As an alternative curstal model, a seismic velocity structure in which velocities are successively increased with the depth is also proposed by the inversion of the time·distance data. With the velocity profile, it is possible to calculate a travel time table which is appropriate to determine the earthquake parameters for the local events.

  • PDF

Beach Deformation Caused by Typhoon Chaba in 2016 Along the Manseongri Coast Related Coastal Improvement Project (연안정비사업이 수행된 만성리 해수욕장에서 2016년 태풍 차바에 의한 해빈변화)

  • Park, Il Heum;Park, Wan-Gyu;Jeong, Seung Myong;Kang, Tae-Soon
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.23 no.6
    • /
    • pp.710-718
    • /
    • 2017
  • After Typhoon Chaba (No.18, 2016) collided with Manseongri Beach, a coastal improvement project was carried out since strong external forces such as waves, storm surges and wave-induced currents were observed to cause beach deformation. The shoreline, beach area and beach volume were periodically surveyed. On the basis of this field data, the beach deformation that occurred at Manseongri Beach has been formally described. Over three months after beach nourishment work began, the beaches were gradually stabilized in terms of natural external forces. However, this stabilization was interrupted by Typhoon Chaba. After two months of typhoon weather, the beach returned to a stable state and no changes were observed until one year after the beach recovery work. Just after the typhoon hit, the shoreline receded from the northern side, where no reduction of external forces occurred, while the rear beach area submerged by breakwater advanced. Also, the beach volume decreased by $3,395m^3$ after the typhoon, due to erosion that occurred on the northern beach, with deposition taking place on the southern backshore area. Therefore, it has been concluded that the coastal improvement project undertaken at Manseongri Beach has significantly contributed to conservation in areas of wave-dominant sediment transport.

A Study on Xu Bing's artworks Contributed to expansion of printmaking in Contemporary Chinese Art (중국 현대미술에서의 판화 매체 확장을 일으킨 쉬빙(徐冰) 작품 연구)

  • Song, Dae-Sup;Cho, Ye-In
    • Cartoon and Animation Studies
    • /
    • s.45
    • /
    • pp.321-343
    • /
    • 2016
  • The purpose of this thesis is to look through the political and social background of China preparing for a new era after getting out of the Communist Party of Mao Zedong, rapid inflow of the Western modernism and the avant-garde art arising in China with the focus of art works of Xu Bing, which contributed to the expansion of printmaking of China. Particularly, 85 New Wave Movement arose by young artists since 1985 and the China/Avant-Garde Exhibition held in Beijing in 1989 are the two important issues which reflect a new change from the traditional Chinese art. The artists of 85 New Wave Movement, who pursued a historical revolution and novelty, worked very actively by leading private exhibitions. Since the Cultural Revolution, the government owned the National Museum of Fine Art Beijing had exhibitions on a large scale displaying various visual arts such as performing art, installation, painting, sculpture but the Chinese government interrupted exhibitions two time due to bold performing art and unconcealed installation. Some artists were even taken to the police when performing art. Under these circumstances, Xu Bing, who majored printmaking, produced one of his major works, Books from the sky(1988), while he was working on various experiments focusing on the production process of printmaking and its repetitiveness. Xu Bing devised letters, carved them in trees and finally created approximately 2000 characters. Going further he displayed it as installation work, which means the developed characters go beyond a printed form, for audiences. This made him earn favorable reviews since it was a form of western art coupled with Chinese contents 'Chinese character'. After he received unfavorable reviews, however, he went to America leaving his last work in China, Ghost Pounding the Wall, in 1990, which was not able to exhibited. In those days, China society was going through a chaotic era thanks to the extinction of the Cultural Revolution and Deng Xiaoping's(1904-1997) reformation after the debacle of Tiananmen Massacre. This study looks into Xu Bing's artworks from his initial print works until he went to the US in 1991 and examines how he performed experiments utilizing reproductivity and plurality of prints tinged with Chinese traditional elements, and ultimately became one of the avant-garde artists representing the period.