• Journal of the Korean earth science society
• /
• v.39 no.6
• /
• pp.593-599
• /
• 2018

The onset times of P- and S-waves are important information to have reliable earthquake locations, 1D or 3D subsurface velocity structures, and other related studies in seismology. As the number of seismic stations increases significantly in recent years, it becomes a formidable task for network operators to pick phase arrivals manually. This study used a simple method to estimate additional P- and S-wave arrival times for local earthquakes when a priori information (event location and time) is available using the Akaike Information Criterion (AIC). We applied the AIC program to the earthquake data recorded at the seismic station located in Gyeongsan (DAG2). The comparisons of automatically estimated phase arrival times with manually picked onset times showed that 95.1% and 93.7% of P-wave and S-wave arrival time estimations, respectively, are less than 0.1 second difference. The higher percentage of agreement presented the method which can be successfully applied to large data sets recorded by high-density seismic arrays.

• PNF and Movement
• /
• v.21 no.1
• /
• pp.107-117
• /
• 2023

Purpose: The aim of this study is to compare the immediate effects of weight-assisting methods on vastus medialis oblique (VMO) and vastus lateralis (VL) muscle activation, on the VMO/VL muscle activation ratio, and on muscle onset time in healthy subjects when ascending stairs. Methods: Healthy participants were randomly assigned to the belt group (n = 11), hand group (n = 11), and control group (n = 11). In the belt group, a belt was wrapped around the sacrum and pulled forward with both hands, moving the center of weight forward, while ascending stairs. The hand group grasped the hips with both hands and climbed stairs, assisting their weight from the rear and moving the center of weight backward, and the control group climbed the stairs without any intervention. Results: Muscle activation of the VMO decreased significantly after the intervention in the belt and hand groups, and activation of the VL muscle in both groups showed a greater decrease than that of the VMO muscle. Further, the VMO/VL muscle activation ratio increased significantly, with an improvement shown in the order of the belt group, hand group, and control group, while muscle onset time also improved in the order of the belt group, hand group, and control group. Conclusion: The belt group demonstrated the greatest effect across all dependent variables, confirming that in clinical practice, these two weight-assisting methods are more effective interventions during stair ascent for patients with knee joint instability, pain, and imbalance than no assistance.

• Korean Journal of Biological Psychiatry
• /
• v.19 no.1
• /
• pp.65-69
• /
• 2012

Objectives : Much is still unknown about the neurophysiological mechanisms or dynamics of the sleep onset process. Detrended fluctuation analysis (DFA) is a new tool for the analysis of electroencephalography (EEG) that may give us additional information about electrophysiological changes. The purpose of this study is to analyze long-range correlations of electroencephalographic signals by DFA and their changes in the sleep onset process. Methods : Thirty channel EEG was recorded in 61 healthy subjects (male:female=34:27, age=$27.2{\pm}3.0$ years). The scaling exponents, alpha, were calculated by DFA and compared between four kinds of 30s sleep-wakefulness states such as wakefulness, transition period, early sleep, and late sleep (stage 1). These four states were selected by the distribution of alpha and theta waves in O1 and O2 electrodes. Results : The scaling exponents, alpha, were significantly different in the four states during sleep onset periods, and also varied with the thirty leads. The interaction between the sleep states and the leads was significant. The means (${\pm}$ standard deviation) of alphas for the states were 0.94 (${\pm}0.12$), 0.98 (${\pm}0.12$), 1.10 (${\pm}0.10$), 1.07 (${\pm}0.07$) in the wakefulness, transitional period, early sleep and late sleep state respectively. The mean alpha of anterior fifteen leads was greater than that of posterior fifteen leads, and the two regions showed the different pattern of changes of the alpha during the sleep onset periods. Conclusions : The characteristic findings in the sleep onset period were the increasing pattern of scaling exponent of DFA, and the pattern was slightly but significantly different between fronto-temporal and parieto-occipital regions. It suggests that the long-range correlations of EEG have a tendency of increasing from wakefulness to early sleep, but anterior and posterior brain regions have different dynamical process. DFA, one of the nonlinear analytical methods for time series, may be a useful tool for the investigation of the sleep onset period.

• Journal of Acupuncture Research
• /
• v.25 no.3
• /
• pp.163-177
• /
• 2008

Objectives : This study was designed to evaluate clinical prognosis factors of Bell's palsy patients. Methods : The 100 subjects were chosen from 262 patients over 20years old who was diagnosised Bell's palsy through Acupuncture & Moxibustion and ENT medical specialist after visiting the hospital within 8days of onset of peripheral facial palsy and after Oriental-Western Medicine Treatment, recovered completely or had over three months cares because of incomplete recovery Oriental-Western Medicine Treatment included Acupuncture Treatment, Herb med treatment, medicines treatment, Physical therapy and Electrodiagnostic Test was operated after 7 to 10days after outbreaks of the disease. Clinical prognosis factors were analyzed using House-Brackmann grading system(HBGS) as a measurement of the degree of Facial Palsy. Collected data were analyzed as Chi-Square test, ANOVA test, Independent-Samples t-test regression analysis using SPSS 12.0 WIN Program. Results : 1. There was a significant difference in the results of treatment according to site of palsy, degree of initial palsy, time of initial recovery and existence of recovery after 3weeks from onset as clinical prognosis factors of Bell's Palsy, However, a statistically significant difference was not shown in the results of treatment according to gender, age, existence of Post Auricular Pain, Hypertension, Diabetes and existence of relapse. 2. As a result of overall treatment, 85% of patients were recovered almost entirely and 15% were not recovered completely. 3. There was a significant difference in the onset of Post Auricular Pain and duration of Post Auricular Pain according to the degree of Post Auricular Pain. 4. There was a significant difference in the degree of initial palsy and degree of palsy after 3weeks from onset according to the existence of Post Auricular Pain. However, a statistically significant difference was not shown in the period of time until initial treatment, The time of initial recovery, (H-B), The period from onset to recovey, ENoG value. Conclusions : Based on the above results, prognosis of Bell's palsy was affected by degree of initial palsy, time of initial recovery and existence of recovery after 3weeks from onset.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.17 no.2
• /
• pp.107-110
• /
• 2006

Background and Objeetives : There are few studies reported that specifically examined the voice onset time(VOT) in patients with bilateral vocal nodules. The purpose of this study was to study the characteristics of voice onset in patients with bilateral vocal nodules. Materials and Methods : 52 female patients with bilateral vocal nodules were examined, aged from 20 to 54 years, and were compared with 25 normal female control group. All subjects produced five repetitions of the voiceless stops $/p^h,\;t^h\;k^h/$ in vowel context /ai_a/. VOT was measured by the time between the release of the stops and the onset of voicing. Results : VOTs of the voiceless stops $/p^h/\;and\;/t^h/$ in patients with bilateral vocal nodules were significantly shorter than those of normal subjects. VOT of the $/k^h/$ in them was shorter than those of normals, but the difference was not significant. This results showed that VOTs of the voiceless stops in patients with bilateral vocal nodules were shorter than those of normal subjects. Conclusion : The rapid onset of voicing in patients with bilateral vocal nodules might be associated with increased laryngeal muscle tension by hard glottal attacks. We suggest that VOT can be a clinically useful acoustic parameter for evaluating voice in patients with bilateral vocal nodules.

• Korean Chemical Engineering Research
• /
• v.53 no.5
• /
• pp.609-613
• /
• 2015

The onset of instability induced by impulsive spin-down of the rigid-body flow placed in the gap between two coaxial cylinders is analyzed by using the energy method. In the present stability analysis the growth rate of the kinetic energy of the base state and also that of disturbances are taken into consideration. In the present system the primary flow is a transient, laminar one. But for the Reynolds number equal or larger than a certain one, i.e. $Re{\geq}Re_G$ secondary motion sets in, starting at a certain time. For $Re{\geq}Re_G$ the dimensionless critical time to mark the onset of vortex instabilities, ${\tau}_c$, is here presented as a function of the Reynolds number Re and the radius ratio ${\eta}$. For the wide gap case of small ${\eta}$, the transient instability is possible in the range of $Re_G{\leq}Re{\leq}Re_S$. It is found that the predicted ${\tau}_c$-value is much smaller than experimental detection time of first observable secondary motion. It seems evident that small disturbances initiated at ${\tau}_c$ require some growth period until they are detected experimentally.

• Journal of Periodontal and Implant Science
• /
• v.23 no.1
• /
• pp.193-200
• /
• 1993

The purpose of this study is to investigate the relationship between occurrence and inducing factors of herpes labialis developed after periodontal therapy and to suggest prediction model of this lesion. A total of 100 patients were studied. A standard schedule was used for interviews of patients. It included demographic information, patient and familial history of recurrent aphthous ulcer and recurrent herpes labialis, history of systemic disease, religion, and emotional state. In case of female patients, the association of dysmenorrhea and onset of recurrent herpes labialis was also observed. After periodontal therapy, some details about therapy, such as the kind of therapy, location, spending time were recorded. At next appointment, the appearance and location of herpes labialis were examined. The frequency of herpes labialis after periodontal therapy was 8% and the location was predominantly mouth angle. The significant relationship was found between the onset of herpes labialis and the history of recurrent herpes labialis, surgical therapy rather than non-surgical therapy, and spending time. The prediction model of herpes labialis was not apparently established with the results of this study. In conclusion it is suggested that we should minimize traumatic manipulation and treatment time to prevent the onset of herpes labialis after periodontal therapy.

• Journal of the Korean Society of Physical Medicine
• /
• v.9 no.4
• /
• pp.425-432
• /
• 2014

PURPOSE: The purpose of this study was to investigate that the differences in sternocleidomastoid muscle activity, neck rotation angle, neck lateral bending angle and neck lateral bending onset time between conditions with and without visual biofeedback during neck rotation. METHODS: Ten male and four female adults with condition of forward head posture were recruited in this study. Subjects conducted to left and right maximal neck rotation under the conditions with and without visual biofeedback. During neck rotation, kinematic data of neck rotation, neck lateral bending movement, and electromyography activities of bilateral sternocleidomastold muscles were collected. Differences in dependent variables between conditions with and without visual biofeedback were analyzed using paired t-test. RESULTS: There were significant decreases in lateral bending angle, while lateral bending movement onset time was delayed significantly when applying visual biofeedback (p<.05). However, there were no significant differences in the activation of left and right sternocleidomastoid muscles and neck rotation angle between conditions with and without visual biofeedback (p>.05). CONCLUSION: These findings suggest that visual biofeedback may be effective for axial rotation of cervical spine during neck rotation in adults with forward head posture.

• The Journal of Korean Physical Therapy
• /
• v.29 no.3
• /
• pp.135-141
• /
• 2017

Purpose: This study was to identify the anticipatory postural adjustment (APA) mechanism which is represented by the onset time of trunk muscles and the displacement of the center of pressure (COP) according to the different base of support (BOS) during upper extremity movement. Methods: Thirty healthy subjects (14 males, 16 females) participated in this study. The movement was performed for 10 trials during each of various BOS (shoulder - width double leg stance, narrow base double leg stance, tandem stance, non-dominant single leg stance) at the 1.2 Hz frequency. Electromyography was used to measure muscle onset time and biorescue was used to measure characteristics of the displacement of COP. Surface bipolar electrodes were applied over the right deltoid anterior, right latissimus dorsi, both rectus abdominis, both internal oblique and both erector spinae. The data were analyzed by repeated one-way ANOVA and Duncan's post hoc test. Results: The study has revealed following. There were significant differences with muscle onset time in each BOS (p<0.01). There were significant differences in characteristics of the COP in each BOS (p<0.01). Conclusion: The study found that the more narrowed the basis requires the more rapid anticipatory postural control in contralateral postural muscle when the upper extremity movement is performed.

• The Bulletin of The Korean Astronomical Society
• /
• v.35 no.2
• /
• pp.45.2-45.2
• /
• 2010

We analyzed onset times of the largest six solar proton events during 1997-2006 of solar cycle 23, as observed at 1AU by two satellites of GOES/SEM (Geostationary Operational Environmental Satellites/the Space Environment Monitor) and SOHO/ERNE (Solar and Heliospheric Observatory/the Energetic and Relativistic Nuclei and Electron). We adopted the time shifted method suggested by Leon Kocharov and determined the path length by Sam Krucker's fitting method. We found some problems of those methods and tried to improve those. In this presentation, we will give details of the energy spectra of the 6 SPE events from the ERNE/HED, and onset time comparison among the SPE, flare, type II burst, and CME.