• Title/Summary/Keyword: pulsation mode

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THEMIS Pi2 observations near dawn and dusk sectors in the inner magnetosphere

  • Kwon, Hyuck-Jin;Kim, Khan-Hyuk;Lee, Dong-Hun;Takahashi, K.;Park, Young-Deuk;Bonnell, J.W.
    • Bulletin of the Korean Space Science Society
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    • 2010.04a
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    • pp.40.3-40.3
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    • 2010
  • The most frequently suggested source for Pi2 pulsations in the inner magnetosphere (L < 4) is standing fast-mode waves trapped in the plasmasphere (i.e., plasmaspheric resonances). They have been considered as the source of low-latitude Pi2 pulsations. The plasmaspheric resonance model suggests that compressional fast-mode waves can be detected at all local times inside the plasmasphere provided reflection of the wave energy is efficient. Until now, however, there are no reports about compressional Pi2s observed in the dayside inner magnetosphere. That is, there is longitudinal limit of inner magnetosphere. In February 2008, THEMIS probes were near dawn and/or dusk sides, which are the transition regions between the nightside and dayside, in the inner magnetosphere (L = 2-4) when low-altitude Pi2s were identified at Bohyun (L = 1.35) station in Korea. Using the THEMIS electric field data, we examined if Pi2s are excited by longitudinally localized disturbances. We found that compressional Pi2s having high coherence with a low-latitude Pi2 pulsation occur on dawnside. However, any compressional pulsations in the Pi2 frequency band were not detected on duskside. This indicates that compressional Pi2s disappear near the duskside. Our observations are discussed with spatial plasmaspheric structure and possible Pi2 mechanisms.

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The quantitative study on the Renying·Qi mouth comparison pulse diagnosis (인영(人迎)·기구비교맥법(氣口比較脈法)의 정량화(定量化)에 관(關)한 연구(硏究))

  • Cho, Myung-Rae;Kim, Moo-Shin;Ryu, Choong-Ryul;Choi, Chan-Hun;Jang, Kyeong-Seon;So, Cheol-Ho;Park, Young-Dae
    • Journal of Acupuncture Research
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    • v.19 no.2
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    • pp.149-163
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    • 2002
  • Objective : We have studied literatures of Renying Qi mouth comparison pulse diagnosis theory and distinguished the excess, deficiency and quick-temper of pulse as the measurement parameter of Renying Qi mouth pulse diagnosis. Methods : We have acquired pulse signals of Renying Qi mouth by using diagnostic equipment of Renying Qi mouth pulsation and estimated reappearance of pulse signals. Results : 1. The measurement parameter of Renying Qi mouth pulse diagnosis distinguishes the excess, deficiency and quick-temper of pulse through relative comparison of Renying Qi mouth. 2. When we acquired the pulse singals of Renying Qi mouth by using diagnostic equipment, the property, measuring area, bias pressure, contact or adhesion state of the sensor are considered. 3. As getting the pulse signal of Renying Qi mouth, the sensor of a sound detective mode is effective. 4. The diagnostic equipment of Renying Qi mouth pulse is assessed as being significant reappearance.

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Characteristics Analysis of CVT with Built-in Crank for Bicycle (자전거용 크랭크 일체형 자동변속기에 대한 특성 해석)

  • Baek, Seung-Yub
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.2
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    • pp.963-969
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    • 2015
  • Bicycle is one of the most popular mode of transport due to the increase of interest in the well-being and environment pollution. Before fabricating a continuously variable transmission that is applied to the actual bicycle, for reducing the problems in the early stage, the reliable simulation program has been applied and the financial problem can be solved. In this paper, in order to confirm the design factor, the stress analysis has been applied. In all models, each link and the joint portion are assumed to be a major design factors, and impact of each link and joints received stress during the operation and it is confirmed by using the CAE. Also, for the analysis region, the special code has been developed to calculate pulsation phenomenon through appropriate mathematical modeling.

KIC 6206751: the first R CMa-type eclipsing binary with ɣ Doradus pulsations

  • Lee, Jae Woo;Park, Jang-Ho
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.84.2-84.2
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    • 2019
  • We present the absolute properties of the double-lined eclipsing binary KIC 6206751 exhibiting multiperiodic pulsations. The Kepler light curve of this system was simultaneously solved with the previously published radial-velocity data. The results indicate that the binary star is a short-period semi-detached system with fundamental parameters of $M_1=1.66{\pm}0.04M_{\odot}$, $M_2=0.215{\pm}0.006M_{\odot}$, $R_1=1.53{\pm}0.02R_{\odot}$, $R_2=1.33{\pm}0.02R_{\odot}$, $L_1=5.0{\pm}0.6L_{\odot}$, and $L_2=0.96{\pm}0.09L_{\odot}$. We applied multiple frequency analyses to the eclipse-subtracted light residuals and detected the 42 frequencies below $2.5days^{-1}$. Among these, three independent frequencies of $f_2$, $f_3$, and $f_4$ can be identified as high-order ($38{\leq}n{\leq}40$) low-degree (l=2) gravity-mode oscillations, whereas the other frequencies may be orbital harmonics and combination terms. The ratios between the orbital frequency and the pulsation frequencies are $f_{orb}:f_{2-4}{\simeq}2:3$, which implies that the ${\gamma}$ Dor pulsations of the detached primary star may be excited by the tidal interaction of the secondary companion. The short orbital period, and the low mass ratio and $M_2$ demonstrate that KIC 6206751 is an R CMa-type star, which is most likely evolving into an EL CVn star. Of seven well-studied R CMa-type stars, our program target is the only eclipsing binary with a ${\gamma}$ Dor pulsating component.

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TIME-SERIES PHOTOMETRY OF VARIABLE STARS IN THE GLOBULAR CLUSTER NGC 288

  • Lee, Dong-Joo;Koo, Jae-Rim;Hong, Kyeongsoo;Kim, Seung-Lee;Lee, Jae Woo;Lee, Chung-Uk;Jeon, Young-Beom;Kim, Yun-Hak;Lim, Beomdu;Ryu, Yoon-Hyun;Cha, Sang-Mok;Lee, Yongseok;Kim, Dong-Jin;Park, Byeong-Gon;Kim, Chun-Hwey
    • Journal of The Korean Astronomical Society
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    • v.49 no.6
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    • pp.295-306
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    • 2016
  • We present the results of BV time-series photometry of the globular cluster NGC 288. Observations were carried out to search for variable stars using the Korea Microlensing Telescope Network (KMTNet) 1.6-m telescopes and a 4k pre-science CCD camera during a test observation from August to December, 2014. We found a new SX Phe star and confirmed twelve previously known variable stars in NGC 288. For the semi-regular variable star V1, we newly determined a period of 37.3 days from light curves spanning 137 days. The light-curve solution of the eclipsing binary V10 indicates that the system is probably a detached system. The pulsation properties of nine SX Phe stars were examined by applying multiple frequency analysis to their light curves. We derived a new Period-Luminosity (P-L) relation, ${\langle}M_V{\rangle}=-2.476({\pm}0.300){\log}P-0.354({\pm}0.385)$, from six SX Phe stars showing the fundamental mode. Additionally, the period ratios of three SX Phe stars that probably have a double-radial mode were investigated; $P_{FO}/P_F=0.779$ for V5, $P_{TO}/P_{FO}=0.685$ for V9, $P_{SO}/P_{FO}=0.811$ for V11. This paper is the first contribution in a series assessing the detections and properties of variable stars in six southern globular clusters with the KMTNet system.

A study on the implementation of Medical Telemetry systems using wireless public data network (무선공중망을 이용한 의료 정보 데이터 원격 모니터링 시스템에 관한 연구)

  • 이택규;김영길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.278-283
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    • 2000
  • As information communication technology developed we could check our blood pressure, pulsation electrocardiogram, SpO2 and blood test easily at home. To check our health at ordinary times is able though interlocking the house medical instrument with the wireless public data network This service will help the inconvenience to visit the hospital everytime and will save the individual's time and cost. In each house an organism data which is detected from the human body will be transmitted to the distance hospital and will be essentially applied through wireless public data network The medical information transmit system is utilized by wireless close range network It would transmit the obtained organism signal wirelessly from the personal device to the main center system in the hospital. Remote telemetry system is embodied by utilizing wireless media access protocol. The protocol is embodied by grafting CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance) protocol falling mode which is standards from IEEE 802.11. Among the house care telemetry system which could measure blood pressure, pulsation, electrocardiogram, SpO2 the study embodies the ECC(electrocardiograph) measure part. It within the ECC function into the movable device and add 900㎒ band wireless public data interface. Then the aged, the patients even anyone in the house could obtain ECG and keep, record the data. It would be essential to control those who had a health-examination heart diseases or more complicated heart diseases and to observe the latent heart disease patient continuously. To embody the medical information transmit system which is based on wireless network. It would transmit the ECG data among the organism signal data which would be utilized by wireless network modem and NCL(Native Control Language) protocol to contact through wireless network Through the SCR(Standard Context Routing) protocol in the network it will be connected to the wired host computer. The computer will check the recorded individual information and the obtained ECC data then send the correspond examination to the movable device. The study suggests the medical transmit system model utilized by the wireless public data network.

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