• Title/Summary/Keyword: Airflow rate

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Korean Adult Normative Data for the KayPENTAX Phonatory Aerodynamic System Model 6600 (KayPENTAX Phonatory Aerodynamic System Model 6600을 이용한 한국 성인의 공기역학적 변수들의 정상치)

  • Kim, Jaeock
    • Phonetics and Speech Sciences
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    • v.6 no.1
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    • pp.105-117
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    • 2014
  • The purpose of this study was to (1) establish a Korean adult normative database for phonatory aerodynamic measures obtained with the KayPENTAX Phonatory Aerodynamic System (PAS) Model 6600, (2) investigate the intra-subject reliability of these measures across three testing sessions, and (3) examine the effect of gender on those measures. 170 healthy normal speakers (70 men and 100 women) between the ages 18 and 49 years participated in the study. The PAS protocol of maximum phonation and voicing efficiency were conducted and 25 measures were obtained. All aerodynamic measures taken in this study demonstrated high intra-subject reliability in clinical aspect. There were no significant effect of gender in the measures related to sound pressure and subglottal pressure. However, significant differences for gender were found for phonation time, airflow rate, expiratory volume, aerodynamic power, SPL range, pitch range, mean pitch, aerodynamic resistance, and aerodynamic efficiency. Clinicians should be aware of significant gender effects in some aerodynamic parameters when interpreting the data obtained from PAS.

An airflow analysis for the reduction of disk flutter in HDD (HDD의 디스크의 진동 감쇄 설계를 위한 공기흐름해석)

  • Kwon, Seong-Min;Koo, S.C.;Kang, Seong-Woo;Hwang, Tae-Yeon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.375-380
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    • 2002
  • As the data storage device market demands higher data transfer rate with higher track density. TMR budget is to be tighter so that even minor improvement is sought in HDD development fields. Disk flutter associated with the turbulent air flow inside the chamber becomes of great interest for the reduction of PES especially at OD. A comparative transient turbulent flow study is presented in this paper for the reduction of disk flutter with different housing designs.

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Ionic Wind Generator With Third Electrode (3전극형 이온풍 발생장치)

  • Hwang, Deok-Hyun;Jung, Hoi-Won;Moon, Jae-Duk
    • Proceedings of the KIEE Conference
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    • 2008.05a
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    • pp.139-140
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    • 2008
  • Cooling systems for electronic equipments are becoming more important. Cooling technologies using natural and forced convection are limited and operated in very low efficiency. A corona discharge is utilized as the driving mechanism for anair pump, which allows for airflow generation with low noise and no moving parts. However they do not enhance the flow rate and overcome the control mechanism of the pump. In this study a point-mesh type air pump, with a third electro de installed near the corona point, has been proposed and investigated by focusing on elevating the ionic wind velocity and power yield. As a result, the significantly enhanced ionic wind velocity and tremendously increased power yield can be obtained with the proposed air pump system.

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An airflow analysis for the reduction of disk flutter in HDD (HDD의 디스크의 진동 감쇄 설계를 위한 공기흐름해석)

  • Kwon, Jeong-min;J. C. Koo;Kang, Seong-Woo;Hwang, Tae-Yeon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.341.2-341
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    • 2002
  • As the data storage device market demands higher data transfer rate with higher track density, TMR budget is to be tighter so that even minor improvement is sought in HDD development fields. Disk flutter associated with the turbulent air flow inside the chamber becomes of great interest for the reduction of PES especially at OD. A comparative transient turbulent flow study is presented in this paper for the reduction of disk flutter with different housing designs.

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Flame Verification using Motion Orientation and Temporal Persistency

  • Hwang, Hyun-Jae;Ko, Byoung-Chul;Nam, Jae-Yeal
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.282-285
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    • 2009
  • This paper proposes a flame verification algorithm using motion and spatial persistency. Most previous vision-based methods using color information and temporal variations of pixels produce frequent false alarms due to the use of many heuristic features. To solve these problems, we used a Bayesian Networks. In addition, since the shape of flame changes upwards irregularly due to the airflow caused by wind or burning material, we distinct real flame from moving objects by checking the motion orientation and temporal persistency of flame regions to remove the misclassification. As a result, the use of two verification steps and a Bayesian inference improved the detection performance and reduced the missing rate.

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An Experimental Study of Disc Warping in Slim-type Optical Disc Drive (Slim-type 광학식 정보저장기기에서의 디스크 변형에 관한 실험적 연구)

  • Lee, Jae-Sung;Rhim, Yoon-Chul
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.676-681
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    • 2003
  • In this paper, we investigated the disc warping in high-speed slim-type optical disc drive. Recently, the information storage devices are increasing track density and higher rotation speed to enhance their recording capacity and their data transfer rate. Generally, ODD used in the Lap-top Computer has small inner space. So, the flow instability of inner space is rapidly increased as its higher rotation speed. An extreme case, the flow instability causes the malfunction of readout at pick-up of drives. The experiments and numerical analysis were carried out for several cases, the result shows the influence of airflow to the disc warping.

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Development of Handheld Respiration Monitoring System (휴대용 호흡 감시장치의 개발)

  • Kwon, S.H.;Kim, H.C.;Choi, S.W.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.183-184
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    • 1998
  • Respiration monitoring is important in many clinical situations due to its relationship to vitality. But present commercial monitoring systems are bulky and expensive, so they are inadequate to be used for long term recording or out-patients application. We have developed a low cost, low power, handhold respiration monitoring system based on airflow measurement. Respiration flow is indirectly detected using a thermister or a themocouple sensor. Real time recording of respiration rate, abnormality detection and apnea alarming are available.

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Mean Value of Aerodynamic Study in Normal Korean (음성검사 중 공기역학적 검사에서 한국인 정상 평균치)

  • 서장수;송시연;권오철;정옥란
    • Proceedings of the KSLP Conference
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    • 1996.11a
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    • pp.79-79
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    • 1996
  • 최근 들어 음성에 대한 일반인들의 관심이 높아지면서 음성이상을 호소하며 이비인후과 외래를 방문하는 환자가 점차적으로 증가하는 추세에 있다. 그러나 이러한 음성이상을 객관적으로 평가할 수 있는 기준이 국내에는 거의 없는 실정이다. 이에 저자들은 본 연구에서 기왕력 상 폐질환이나 신경계질환, 후두질환을 앓은 적이 없으며 음성조율 기관에 이상이 없고 정상적인 청력을 가진 10세에서 69세까지의 무작위 추출된 정상 한국인 남자 112명과 여자 122명을 대상으로 Aerophone II voice function analyzer를 이용하여 공기역동학적 검사 중 최대발성지속시간(maximum phonation time), 평균호기류율(mean airflow rate), 발성율(phonation quotient), 발성시 기류량(phonatory flow volume) 및 성문하압(subglottal pressure)의 정상 한국인의 남녀 년령별 평균치를 측정하고자 하였다. (중략)

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A Study on Natural Ventilation Performance by Periodic Outdoor Pressure Fluctuations (주기적인 외부 압력변동에 의한 자연환기성능 연구)

  • Lee, Seung-Yeon;Yom, Chol-Min;Han, Hwa-Taek
    • Proceedings of the SAREK Conference
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    • 2005.11a
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    • pp.27-32
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    • 2005
  • This paper investigates the effects of outdoor pressure fluctuations on natural ventilation through openings of a building envelope. The ventilation airflow rate depends on the magnitude and the period of the pressure fluctuations, the size of the opening compared to the space volume, and the resistance characteristics of the opening. Non-dimensional parameters have been derived, which determine indoor pressure responses due to outdoor pressure fluctuations. The flow regions are categorized into synchronized region, opening resistance region, and transition region depending on the non-dimensional parameters.

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Analysis of Ventilation Rates in Residential Buildings using a Multizone Network Model (멀티존 네트워크 모델을 이용한 주거용 건물의 환기량 분석)

  • Cha, Ji-Hyoung;Park, Cheol-Hun;Kim, Yeong-Ha;Baek, Chang-In;Han, Hwa-Taek
    • Proceedings of the SAREK Conference
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    • 2005.11a
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    • pp.45-50
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    • 2005
  • The supply outdoor airflow rates are calculated and analyzed using a multizone network model in a high-rise residential apartment. The system parameters include parameters related to weather conditions, building conditions, operation conditions, and facility conditions. Simulations are conducted according to the method of design of experiments and analysis of variance is conducted to investigate the effects of parameters on ventilation rate. A correlation equation is derived to predict ventilation rates of the building depending on the various parameters.

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