• Geophysics and Geophysical Exploration
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• v.11 no.2
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• pp.137-147
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• 2008

Fault rupture directivity of the Odaesan earthquake, which was inferred to be the main cause of the high PGAvalue (> 0.1 g) unusually observed at the near-source region, was analyzed by using the data from the nearby (R < 100 km) dense seismic stations. The Boatwright's method (2007) was adopted for this purpose in which the azimuth and takeoff angle of the unilateral rupture directivity function could be estimated based on the relative peak ground-motions of seismic stations resulting from the nature of the rupture directivity. In this study, the approximate values of the relative peak ground-motions was derived from the difference between the log residuals of the point-source spectral model (Boore, 2003) for the main and secondary events based on the Random Vibration Theory. In this derivation, the spectral difference for a frequency range between the source corner frequencies of main and secondary events was considered to reflect only the effect of the fault directivity. The inversion result of the model parameters for the fault directivity function showed that the fault-plane of NWW-SEE direction dipping steeply to the North with high rupture velocity near upward in SE direction is responsible for the observed high level of ground-motion at the near-source region.

• Journal of The Korean Astronomical Society
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• v.36 no.3
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• pp.81-87
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• 2003

It is suggested that a flying-by star in a hot accretion disk may cool the hot accretion disk by the Comptonization of the stellar emission. Such a stellar cooling can be observed in the radio frequency regime since synchrotron luminosity depends strongly on the electron temperature of the accretion flow. If a bright star orbiting around the supermassive black hole cools the hot disk, one should expect a quasi-periodic modulation in radio, or even possible an anti-correlation of luminosities in radio and X-rays. Recently, the unprecedentedly accurate infrared imaging of the Sagittarius A$\ast$ for about ten years enables us to resolve stars around it and thus determine orbital parameters of the currently closest star S2. We explore the possibility of using such kind of observation to distinguish two quite different physical models for the central engine of the Sagittarius A$\ast$, that is, a hot accretion disk model and a jet model. We have attempted to estimate the observables using the observed parameters of the star S2. The relative difference in the electron temperature is a few parts of a thousand at the epoch when the star S2 is near at the pericenter. The relative radio luminosity difference with and without the stellar cooling is also small of order $10^{-4}$, particularly even when the star S2 is near at the pericenter. On the basis of our findings we tentatively conclude that even the currently closest pass of the star S2 is insufficiently close enough to meaningfully constrain the nature of the Sagittarius A$\ast$ and distinguish two competing models. This implies that even though Bower et al. (2002)have found no periodic radio flux variations in their data set from 1981 to 1998, which is naturally expected from the presence of a hot disk, a hot disk model cannot be conclusively ruled out. This is simply because the energy bands they have studied are too high to observe the effect of the star S2 even if it indeed interacts with the hot disk. In other words, even if there is a hot accretion disk the star like S2 has imprints in the frequency range at v $\le$ 100 MHz.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.559-563
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• 2015

Monitor of All-sky X-ray Image (MAXI) is a Japanese X-ray all-sky surveyer mounted on the International Space Station (ISS). It has been scanning the whole sky since 2009 during every 92-minute ISS rotation. X-ray transients are quickly found by the real-time nova-search program. As a result, MAXI has issued 133 Astronomer's Telegrams and 44 Gamma-ray burst Coordinated Networks so far. MAXI has discovered six new black holes (BH) in 4.5 years. Long-term behaviors of the MAXI BHs can be classified into two types by their outbursts; a fast-rise exponential-decay type and a fast-rise flat-top one. The slit camera is suitable for accumulating data over a long time. MAXI issued a 37-month catalog containing 500 sources above a ~0.6 mCrab detection limit at 4-10 keV in the region ${\mid}{b}{\mid}$ > $10^{\circ}$. The SSC instrument utilizing an X-ray CCD has detected diffuse soft X-rays extending over a large solid angle, such as the Cygnus super bubble. MAXI/SSC has also detcted a Ne emission line from the rapid soft X-ray nova MAXI J0158-744. The overall shapes of outbursts in Be X-ray binaries (BeXRB) are precisely observed with MAXI/GSC. BeXRB have two kinds of outbursts, a normal outburst and a giant one. The peak dates of the subsequent giant outbursts of A0535+26 repeated with a different period than the orbital one. The Be stellar disk is considered to either have a precession motion or a distorted shape. The long-term behaviors of low-mass X-ray binaries (LMXB) containing weakly magnetized neutron stars are investigated. Transient LMXBs (Aql X-1 and 4U 1608-52) repeated outbursts every 200-1000 days, which is understood by the limit-cycle of hydrogen ionization states in the outer accretion disk. A third state (very dim state) in Aql X-1 and 4U 1608-52 was interpreted as the propeller effect in the unified picture of LMXB. Cir X-1 is a peculiar source in the sense that its long-term behavior is not like typical LMXBs. The luminosity sometimes decreases suddenly at periastron. It might be explained by the stripping of the outer accretion disk by a clumpy stellar wind. MAXI observed 64 large flares from 22 active stars (RS CVns, dMe stars, Argol types, young stellar objects) over 4 years. The total energies are $10^{34}-10^{36}$ erg $s^{-1}$. Since MAXI can measure the spectrum (temperature and emission measure), we can estimate the size of the plasma and the magnetic fields. The size sometimes exceeds the size of the star. The magnetic field is in the range of 10-100 gauss, which is a typical value for solar flares.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.4
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• pp.46-56
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• 2016

Objectives: The purpose of this study is to evaluate the clinical effects of Muscle Energy Technique (MET) for peroneal nerve palsy after normal delivery. Methods: Two patients with peroneal nerve palsy were treated with acupuncture, moxibustion, cupping and MET. MET was performed in piriform, gluteus medius, anterior tibial and adductor muscles. To evaluate the effect of MET, we analyzed Ankle dorsiflexion range of motion (ROM), Manual Muscle Test (MMT), Numerical Rating Scale (NRS) and Ankle Hindfoot Scale (AHS). Results: In Case 1, ROM score was changed from −5 to 20, and MMT score was changed from 0 to 4. NRS score was changed from 5 to 1, and her AHS score was changed from 54 to 94 after treatment. In Case 2, ROM score was changed from 0 to 20, and her MMT score was changed from 1 to 5. NRS score was changed from 4 to 1, and her AHS score was changed from 64 to 97 after treatment. Conclusions: MET may be a useful treatment for patients who, shortly after childbirth or while breastfeeding, strongly refuse to treat the irritation.

• Journal of muscle and joint health
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• v.3 no.2
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• pp.177-193
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• 1996

The purpose of this study was to test whether Yoga exercise, one of muscle relaxation, helps to relieve chronic low back paln. Sample were selected from nurses who were worked at K medical center in the period from March 18 to April 23, 1996. The sample size was fifteen. The research design was one-group pretest-posttest design. To test the major research question, this study had the following procedure. The pretest included measuring individuals' degree of pain and discomfort depending on the scope and types of an range of motion, and their pain by their activity of daily living(ADL). The treatment was conducted twice every other week. The reason why this study had twice observations was to control history effect and maturation which treat internal validity in the research design of this study. In this research design, a treatment was to expose Yoga exercise to samples. The exercise was taken in 30 minutes per day for four days in a week (Two consecutive days and twice every other day). The posttest included re-measuring the individuals' the degree of pain and discomfort, and their pain by their ADL. Several hypotheses concerning effect of Yoga exercise was analyzed by the paired t-test, comparing the difference scores between pre and post tests. The results of this study was as follows. The first hypothesis that the post-treatment group taking the Yoga exercise had the pain score lower than the pre-treatment group was supported(t=3.31, p=.005). The second hypothesis that the discomfort score of the post-treatment group had lower than does that of the pre-treatment group was supported(t=2.75, p=.016). The third hypothesis that the post-treatment group had the pain score by ADL lower than does the pre-treatment group was supported(t=5.52, p=.000). In summary, this study examined the effect of a yoga exercise, one of muscle relaxation, on those who were suffered from chronic low back pain. The effect measured by the degree of pain and discomfort with a visual analog scale was statistically significant. The degree of pain according to postures in ADL also showed statistical significance. These findings showed that a yoga exercise was effective to alleviation of chronic low back pain. A pretest-posttest control group design, however, needs to get more accurate results since the design satisfies Internal validity. Consequently, yoga as an exercise cure improves an interaction between muscles and articulations, and performance of ADL for those suffered from chronic low back pain. Furthermore, this positive impact may be an effective method as nursing intervention for their physical, mental, emotional, social, and psychological recovery.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.181-189
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• 2002

Purpose: We try to evaluate the functional outcomes of the ankle with isokinetic plantaflexion torque for acute achilles tendon rupture cases those treated by primary repair with the Krackow suture technique and early rehabilization. Materials and Method: The authors studied retrospectively, 15 patients of acute achilles tendon rupture treated and followed over six months, from July 1997 to May 2001. There were 12 men and 3 women, and mean age was 39.6year. The repair method of ruptured tendon was single or double Krackow suture technique. One week(5days-2weeks) after operation, early ROM with ankle-foot orthosis was started. We used Arner-Lindholm Scale for the clinical evaluation and analyzed patient's satisfaction and subjective strength deficit. We analyzed the dorsiflexion peak torque and plantarflexion peak torque of the ankle statistically with strength test with Cybex dynamometer. Result: In clinical results, we had 11 excellent cases(73%) and 3 good cases(20%). In patients satisfaction degree, 11 excellent cases(66.6%), 3 good cases(20%) and 2 fair cases(13.4%). And in strength deficit, 3 none deficit (20%), 9 minimal deficit(60%). We evaluated the isokinetic plantar flexion torque in 3months or 6months after operation. After 3 months, isokinetic test showed the mean functional deficits, 32% and 25% at $30^{\circ}$ and $120^{\circ}/sec$, in 7 cases(46.6%) of 15 cases respectively. After 6 months, the mean deficits were in 21%, 24% at 30. and $120^{\circ}/sec$, respectively. At 3 and 6 months' follow up, absolute value of isokinetic test showed increase of 25. 31bs to 421bs and 19.61bs to 271bs at $30^{\circ}$ and $120^{\circ}/sec$, respectively. Conclusion: We had good result for acute achilles tendon rupture treated by Krakow suture technique and early range of motion exercise of the ankle. After 6 months, strength deficit was 21% in all of cases but were able to return pre-injured state. This study shows Krakow suture technique was recommended method for primary repair and early rehabilization of achilles tendon ruptue.

• Journal of Korean Foot and Ankle Society
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• v.18 no.3
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• pp.108-114
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• 2014

Purpose: Ligament reattachment technique using a suture anchor appears to show satisfactory functional outcomes and mechanical stability compared with conventional bone tunnel technique. This study was prospectively conducted in order to evaluate functional outcomes of modified Brostrom procedures using the suture bridge technique for chronic ankle instability in athletes. Materials and Methods: Twenty eight athletes under 30 years of age were followed for more than two years after undergoing the modified Brostrom procedure using the suture bridge technique. Functional evaluation consisted of the foot and ankle outcome score (FAOS), foot and ankle ability measure (FAAM) score. Range of motion and time to return to exercise were evaluated using a periodic questionnaire. Talar tilt angle and anterior talar translation were measured through stress radiographs for evaluation of mechanical stability. Results: FAOS improved significantly from preoperative mean 59.4 points to 91.4 points (p<0.001). Daily living and sport activity scores of FAAM improved significantly from preoperative mean 50.5, 32.5 points to 94.8, 87.3 points, respectively (p<0.001). Talar tilt angle and anterior talar translation improved significantly from preoperative mean $16.8^{\circ}$, 13.5 mm to $4.2^{\circ}$, 4.1 mm at final follow-up (p<0.001). Times to return to exercise were as follows: mean 10.2 weeks in jogging, 15.4 weeks in spurt running, 13.1 weeks in jumping, 11.5 weeks in walking on uneven ground, 9.1 weeks in standing on one leg, 7.2 weeks in tip-toeing gait, 8.4 weeks in squatting, and 10.6 weeks in descending stairs. Conclusion: Modified Brostrom procedure using the suture bridge technique showed satisfactory functional outcomes for chronic ankle instability in athletes. Optimal indication and cost-effectiveness of the suture bridge technique will be studied in the future.

• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.165-182
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• 1997

The aim of this paper is to clarify geomorphic features on talus within ${\check{O}}rumkol$ and the origin of ${\check{O}}rumkol$. ${\check{O}}rumkol$ is located in Milyang of Kyungnam province, in South Korea. ${\check{O}}rumkol$ is good area to study talus. because it is characterized by following three geomorphic landscapes : free face surrounding ${\check{O}}rumkol$ ; ${\check{O}}rumkol$ with deep and wide valley floor ; lots of taluses typically developing within ${\check{O}}rumkol$. The main results can be summarized as follows: 1) The origin of ${\check{O}}rumkol$ may be suggested two assumptions : one is that its origin have been resulted from intrusion structure(intrusive rock might capture less resistant rock as tuff) ; the other is that its origin have been resulted from volcanic depression after intrusion or eruption. But these assumptions are not obvious. therefore more geological evidences will be supplemented after this 2) The characteristics of ${\check{O}}rumkol$ talus (1) Pattern ${\check{O}}rumkol$ taluses are tongue-shaped or cone-shaped in appearance. They are $50{\sim}200m$ in length and the range of the maximum width from 25 to 115m and one of their mean slope gradient from 32 to $36^{\circ}$ (2) Origin ${\check{O}}rumkol$ taluses have been formed under periglacial environment in the last glacial age and they are classified into rock fall talus type, considering in conjunction with the shape, hardness, sorting, weathering conditions of constituent debris. (3) The stage of landform development ${\check{O}}rumkol$ talus slope profiles are mainly concave slope. This concave slope type was eventually caused by talus creep at the lower end of the talus. That means new additions of debris from the free face have virtually ceased and there is no evidence of recent motion in the deposit. Now it is predominant that vegetation cover is gradually increasingly. Therefore ${\check{O}}rumkol$ taluses appear to be relict form stage. at present.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.7-13
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• 2009

Purpose: To evaluate the clinical and radiological results of arthroscopic tuberoplasty for irreparable massive rotator cuff tears. Materials and Methods: Eleven patients underwent arthroscopic tuberoplasty for irreparable massive rotator cuff tears between December 2004 and April 2007. The mean follow-up period was 17.3 months, and the average age at the time of surgery was 61.7-year-old. Five cases underwent arthroscopic tuberoplasty and 6 cases had arthroscopic subacromial decompression and tuberoplasty, simultaneously. Results: The average Constant score improved from 61.8 to 86.9 and the average UCLA score changed from 14.8 to 31.8 with 6 excellent, 3 good and 2 poor results (p=0.003). The active forward flexion improved from $111.8^{\circ}$ to $154.1^{\circ}$(p=0.011). The acromiohumeral interval increased from 3.94 mm preoperatively to 4.22 mm postoperatively (p=0.12). In the poor UCLA score group, the acromiohumeral interval changed from 1.67 mm preoperatively to 0.94 mm postoperatively. Conclusion: Arthroscopic tuberoplasty may be a second option to relieve the pain of irreparable massive rotator cuff tears and improve the range of motion. However, good results could not be expected if the acromiohumeral interval is < 2 mm preoperatively and decreased postoperatively.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.1-6
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• 2009

Purpose: To evaluate and report the clinical and radiological outcomes of open reduction and internal fixation with a mini-T plate for unstable distal clavicle fractures. Materials and Methods: From December 2004 to July 2007, fifteen patients who had a fracture of the distal clavicle (Neer type II fracture) were treated with an open reduction and internal fixation using a mini-T plate. They were followed up for a minimum of one year and the clinical and radiological results were analyzed. Results: The average time to fracture union was 3.1(3~4) months. There were no complications, such as deep infection or fixation loss. The mean ASES score was 97 points (85~100points) at the last follow up period, and 14 patients had a full range of motion of the shoulder. Conclusion: Open reduction and internal fixation with a mini-T plate for unstable distal clavicle fracture is a good surgical method with good clinical and radiological results.