• Title/Summary/Keyword: Onset time method

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A Study of QRS Complex Detection using the Spatial Velocity (공간속도 알고리즘을 이용한 QRS 컴플레스 검출에 관한 연구)

  • 권혁제;이명호
    • Journal of Biomedical Engineering Research
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    • v.17 no.2
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    • pp.263-273
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    • 1996
  • The time instants, at which QRS complexes are detected, are used in the electrocardioyam rhythm analysis. Hence, it is necessary that all QRS complexes are detected and that no other waves or artifacts are wrongly labeled as such. These time instants are also used in other tasks as an indication of the location of significant events in the ECG. For example, the QRS typification algorithm uses these points to define the region of interest for complex comparison and alignment. When waveform recognition is drone for each complex, these points are used to define search intervals in which the onset and the end of the QRS nmplex have to be found This paper proposes the method for the detection of QRS complexes and decision rule for the classification scheme. The efficiency of the detection is demonstrated with the aid of an internationally validated CSE(Common Standard for Quantitative Electrocardioyaph) data set 3 and 4.

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ESPI Simulation for the Vibration Modes of the Thin Right-Angled Plate (얇은 직각판의 진동 모드에 대한 ESPI 시뮬레이션)

  • 장순석
    • Journal of KSNVE
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    • v.9 no.3
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    • pp.509-516
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    • 1999
  • The ESPI (Electronic Speckle Pattern Interferometry) algorithm has been simulated to calculate vibrational modes of a thin right-angled STS304 plate. The phase transformation of the reference wave of the ESPI is carried out only one time during vibration in order to clarify ESPI speckle patterns. Two dimensional vibrational modes are calculated from one ESPI pattern before vibration onset and two ESPI patterns during vibrations but with and without the phase transformation. The ESPI harmonic results are compared with those derived from the finite element method (FEM), and they agree very well. Additionally a phase unwrapping algorithm has been newly developed to derive a displacement map from an ESPI phase map.

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Effect of Hip Adduction Position on the Vastus Medialis Oblique and Vastus Lateralis During Closed Kinetic Chain Exercise in Sitting Posture

  • Cha, Yong-su;Jeon, Hye-seon;Yi, Chung-hwi;Kwon, Oh-yun;Choi, Bo-ram
    • Physical Therapy Korea
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    • v.23 no.2
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    • pp.75-83
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    • 2016
  • Background: Several studies have discussed diverse exercise methods considered to be useful for the selective contraction of the vastus medialis oblique (VMO) muscle for the treatment of patellofemoral pain syndrome. Some studies have reported that exercise methods, including hip adduction, in closed kinetic chain exercises are more effective in terms of the muscle activation of the VMO and the timing of the muscle's initial contraction. We focused on isometric contraction during a closed kinetic chain exercise with hip adduction. Objects: The purpose of this study was to examine muscle activation in the VMO and the vastus lateralis (VL) and the onset time difference between their initial contractions via closed kinetic chain isometric quadriceps femoris exercises including hip adduction. Methods: In total, 36 healthy subjects adopted two hip positions during isometric contraction of the quadriceps femoris in a closed kinetic chain exercise (hip neutral and hip adduction position). Statistical analyses were conducted using a paired t-test (${\alpha}=.05$). Results: Isometric contraction of the quadriceps femoris in a closed kinetic chain exercise caused a greater increase in VMO muscle activity in the hip adduction position [$52.68{\pm}22.21$ percentage of maximal voluntary isometric contraction (%MVIC)]than the hip neutral position ($43.43{\pm}19.85%MVIC$). The onset time difference (VL-VMO) decreased more in the hip adduction position ($-82.14{\pm}34.2ms$) than the hip neutral position ($73.94{\pm}2.94ms$). Conclusion: We recommend this exercise as a clinically useful therapeutic method for patients with patellofemoral pain syndrome due to weakening of the VMO muscle and lateral inclination of the patella.

Activities of Daily Living and Fatigue in the Stroke Patients (뇌졸중 환자의 일상생활동작 수행정도와 피로감에 관한 연구)

  • Park, Geun-Ok;Shin, Su-Jin
    • The Korean Journal of Rehabilitation Nursing
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    • v.13 no.1
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    • pp.23-31
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    • 2010
  • Purpose: The purpose of this study were to describe the level of activities of daily living (ADLs) and fatigue of stroke patients and to identify related factors of ADLs and fatigue. Method: A sample of 132 were used who were recovering from stroke. The face-to-face interviews were conducted to collect data. The levels of ADLs and fatigue were evaluated using the Modified Barthel Index and Kim's fatigue scale respectively. A series of t-test and analysis of variance analyses were conducted to examine study purposes using SPSS 15.0. Results: The levels of fatigue and ADLs were 65.6 (SD=16.52) and 74.6 (SD=22.32) respectively. Significantly poorer ADLs were found: women (t=2.05, p=.001), older people aged ${\geq}$ 70 years (F=2.74, p=.046), the duration of onset (F=4.34, p=.006), the use of assist devices (F=35.64, p<.001), the parts of paralysis (F=4.25, p=.007), the time to attack (F=3.34, p=.039), and accompanying symptoms (F=15.23, p<.001). There was a significant difference in fatigue with patients with lower accompanying symptoms having lower fatigue (F=11.08, p<.001). Conclusion: These findings suggest gender, the duration from onset, the use of assist device, the parts of paralysis, the time to attack and accompanying symptoms were significant factors of the ADLs and fatigue post stroke. These factors should be considered when developing and testing nursing intervention programs for stroke survivors.

Single Centre Experience on Decision Making for Mechanical Thrombectomy Based on Single-Phase CT Angiography by Including NCCT and Maximum Intensity Projection Images - A Comparison with Magnetic Resonance Imaging after Non-Contrast CT

  • Kim, Myeong Soo;Kim, Gi Sung
    • Journal of Korean Neurosurgical Society
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    • v.63 no.2
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    • pp.188-201
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    • 2020
  • Objective : The purpose of this study was to suggest that computed tomography angiography (CTA) is valuable as the only preliminary examination for mechanical thrombectomy (MT). MT after single examination of CTA including noncontrast computed tomography (NCCT) and maximum intensity projection (MIP) improves door-to-puncture time as well as results in favorable outcomes. Methods : A total of 157 patients who underwent MT at Dong Kang Medical Center from April 2015 to March 2019 were divided into two groups based on the examination performed prior to MT : CTA group who underwent CTA with NCCT and MIP, and NCCT+magnetic resonance image (MRi) group who underwent MRI including perfusion images after NCCT. In the two groups, time to CTA imaging or NCCT+MRi imaging after symptom onset, and time to arterial puncture and reperfusion were characterized as time-related outcomes. The evaluation of vascular recanalization after MT was defined as a modified thrombolysis in cerebral infarction (mTICI) scale. National Institutes of Health Stroke Scale (NIHSS) was assessed at the time of the visit to the emergency room and modified Rankin Scale (mRS) was assessed after 90 days. Results : Typically, there were 34 patients in the CTA group and 33 patients in the NCCT+MRi group. A significantly shorter delay for door-to-puncture time was observed (mean, 86±22.1 vs. 176±47.5 minutes; <0.01). Also, a significantly shorter door-to-imege time in the CTA group was observed (mean, 13±6.8 vs. 93±30.8 minutes; p<0.01). Moreover, a significantly shorter onset-to-puncture time was observed (mean, 195±128.0 vs. 314±157.6 minutes; p<0.01). Reperfusion result of mTICI ≥2b was 100% (34/34) in the CTA group and 94% (31/33) in the NCCT+MRi group, and mTICI 3 in 74% (25/34) in the CTA group and 73% (24/33) in the NCCT+MRi group. Favorable functional outcomes (mRS score ≤2 at 90 days) were 68% (23/34) in the CTA group and 60% (20/33) in the NCCT+MRi group. Conclusion : A single-phase CTA including NCCT and MIP images was performed as a single preliminary examination, which led to a reduction in the time of the procedure and resulted in good results of prognosis. Consequently, it is concluded that this method is of sufficient value as the only preliminary examination for decision making.

Automatic Vowel Onset Point Detection Based on Auditory Frequency Response (청각 주파수 응답에 기반한 자동 모음 개시 지점 탐지)

  • Zang, Xian;Kim, Hag-Tae;Chong, Kil-To
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.1
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    • pp.333-342
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    • 2012
  • This paper presents a vowel onset point (VOP) detection method based on the human auditory system. This method maps the "perceptual" frequency scale, i.e. Mel scale onto a linear acoustic frequency, and then establishes a series of Triangular Mel-weighted Filter Bank simulate the function of band pass filtering in human ear. This nonlinear critical-band filter bank helps greatly reduce the data dimensionality, and eliminate the effect of harmonic waves to make the formants more prominent in the nonlinear spaced Mel spectrum. The sum of mel spectrum peaks energy is extracted as feature for each frame, and the instinct at which the energy amplitude starts rising sharply is detected as VOP, by convolving with Gabor window. For the single-word database which contains 12 vowels articulated with different kinds of consonants, the experimental results showed a good average detection rate of 72.73%, higher than other vowel detection methods based on short-time energy and zero-crossing rate.

The Clinical Analysis of 104 Sanhupung Patients that visited at an Oriental Medicine Hospital. (일개 한의대 부속 한방병원에 산후풍으로 내원한 환자 104례에 대한 실태 분석)

  • Jang, Se-Ran;Park, Young-Sun;Kim, Dong-Chul
    • The Journal of Korean Obstetrics and Gynecology
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    • v.23 no.3
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    • pp.192-204
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    • 2010
  • Purpose: Sanhupung's pathological conditions is different from non-postpartum's disease. So it is important to analyze Sanhupung's construction, onset factors and Oriental theraphy. Methods: We studied 104 Sanhupung women visiting $\bigcirc\bigcirc$ hospital form January 2008 to December 2009. We analyzed the general characteristics, kinds of symptoms and Oriental theraphy's present condition. Also We compared patients' age, the number of live births and delivery month to the National Statistical Office's results. Results: 1. Patients over the age of 30, who have one child and who gave birth in September(14.42%) and in Summer(43.26%) occupied the highest percentage. But delivery method was not correlated with Sanhupung. 2. Musculo-skeletal symptoms(42.13%) were the most common symptoms. Wrist, waist, knees(59.59%) were the most common pain areas and the other pain symptoms (40.21%) appeared a significant portion of cases respectively. 3. In the 21~30days after delivery, the most patients visited. The number of patients admitted within 30 days after delivery or within 90 days was small comparing with Sanhupung onset. Patients treated within 10 days(47.12%) and treated only herb medicine(54.90%) were the most common. And the patients responded satisfacion or over were 88.46%. Conclusion: Patients' age, the number of born babies, delivery time were correlated with Sanhupung symptoms, but the method of delivery was not associated. And musculo-skeletal symptoms were the most common symptoms. Sanhupung patient's treatment period and methods were limited.

Sample size calculation for comparing time-averaged responses in K-group repeated binary outcomes

  • Wang, Jijia;Zhang, Song;Ahn, Chul
    • Communications for Statistical Applications and Methods
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    • v.25 no.3
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    • pp.321-328
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    • 2018
  • In clinical trials with repeated measurements, the time-averaged difference (TAD) may provide a more powerful evaluation of treatment efficacy than the rate of changes over time when the treatment effect has rapid onset and repeated measurements continue across an extended period after a maximum effect is achieved (Overall and Doyle, Controlled Clinical Trials, 15, 100-123, 1994). The sample size formula has been investigated by many researchers for the evaluation of TAD in two treatment groups. For the evaluation of TAD in multi-arm trials, Zhang and Ahn (Computational Statistics & Data Analysis, 58, 283-291, 2013) and Lou et al. (Communications in Statistics-Theory and Methods, 46, 11204-11213, 2017b) developed the sample size formulas for continuous outcomes and count outcomes, respectively. In this paper, we derive a sample size formula to evaluate the TAD of the repeated binary outcomes in multi-arm trials using the generalized estimating equation approach. This proposed sample size formula accounts for various correlation structures and missing patterns (including a mixture of independent missing and monotone missing patterns) that are frequently encountered by practitioners in clinical trials. We conduct simulation studies to assess the performance of the proposed sample size formula under a wide range of design parameters. The results show that the empirical powers and the empirical Type I errors are close to nominal levels. We illustrate our proposed method using a clinical trial example.

Three-Dimensional Transition in the Wake of a Circular Cylinder By Direct Numerical Simulation (DNS에 의한 원주 후류에서의 3차원 천이)

  • Knag, S.J.;Tanahashi, M.;Miyauchi, T.;Mo, J.O.;Lee, Y.H.
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.570-577
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    • 2001
  • Three-dimensional time-dependent flow past a circular cylinder is numerically investigated using direct numerical simulation for Reynolds number 280 and 300. The higher-order finite difference scheme is employed for the spatial distributions along with the second order Adams-Bashforth and the first order backward-Euler time integration. In x-y plane, the convection term is applied by the 5th order upwind scheme and the pressure and viscosity terms are applied by the 4th order central difference. And in spanwise, Navier-Stokes equation is distributed using of Spectral Method. At Reynolds number 259 the two-dimensional wake becomes linearly unstable to a second branch of modes with wavelength about 1.0 diameters at onset (B-mode). Present results of three-dimensional effects of in wake of a circular cylinder is represented with spanwise and streamwise vorticity contours as Reynolds numbers.

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The Role of the Electroglottography on the Laryngeal Articulation of Speech (전기 Glottography(EGG)를 이용한 후두구음역학적 특성)

  • 홍기환;박병암;양윤수;서수영;김현기
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.8 no.1
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    • pp.18-26
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    • 1997
  • There are two types of phonetic study, acoustic and physiologic, for differentiating the three manner categories of Korean stop consonants. On the physiologic studies, there are endoscopic, electromyographic(EMG), electroglottographic(EGG) and aerodynamic studies. In this study, I tried to investigate general features of Korean stops using EGG study for the open quotient of vocal fold and baseline shift during speech, and aerodynamic characteristics for e subglottal air pressure, air flow and glottal resistance at consonants. On the aerodynamic study, the glottalized and aspirated stops may be characterized by e increasing subglottal pressure comparing with lenis stop at consonants. The airflow is largest in the aspirated stops followed by lenis stops and glottalized. The glottal airway resistance (GAR) showed highest in the glottalized followed by the lenis, but lowest in e aspirated during e production of consonants, and showed highest in e aspirated, but low in the glottalized and lenis during the production of vowel. The glottal resistance at consonant showed significant difference among consonants and significant interaction between subject and types of consonant. The glottal resistance at vowel showed significant difference among consonants, and e interaction occured between subject and types of consonant. The electroglottography(EGG) has been used for investigating e functioning of e vocal folds during its vibration. The EGG should be related to the patterns of the vocal fold vibration during phonation in characterizing the temporal patterns of each vibratory cycle. The purpose of this study is to investigate the dynamic change of EGG waveforms during continuous speech. The dynamic changes of EGG waveforms fir the three-way distinction of Korean stops were characterized that the aspirated stop appears to be characterized by largest open quotient and smallest glottal contact area of the vocal folds in e initial portion of vocal fold vibration ; the lenis stop by moderate open quotient and glottal contact area ; but the glottalized stop by smallest open quotient and largest glottal contact area. There may be close relationship between the OQ(open quotient) in the initial voice onset and the glottal width at the time of consonant production, the larger glottal width just before vocal fold vibration results in the smaller OQ of the vocal fold vibration in the initial voice onset. The EGG changes of baseline shift during continuous speech production were characterized by the different patterns for the three types of Korean consonants. The small and less stiffness change of baseline shift was found for the lenis and the glottalized, and the largest and stiffest change was found for the aspirated. On the baseline shift for the initial voice onset, they showed so similar patterns with for the consonant production, larger changed in the aspirated. for the lenis and the glottalized during the initial voice onset, three subjects showed individual difference each other. I suggest at s characteristics were strongly related with articulatory activity of vocal tract for the production of consonant, especially for the aspirated stop. The suspecting factors to affect EGG waveforms are glottal width, vertical laryngeal movement and the intrapharyngeal pressure to neighboring tissue during connected spech. So the EGG may be an useful method to describe laryngeal activity to classify pulsing conditions of the larynx during speech production, and EGG research can be controls for monitoring the vocal tract articulation, although above factors to affect EGG would have played such a potentially role on vocal fold vibratory behavior obtained using consonant production.

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