• Journal of the Korean Geotechnical Society
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• v.32 no.12
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• pp.15-22
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• 2016

The magnitude of the lateral resistance that resists the lateral movement of the pile is controlled by the amount of the pile movement and the strength and stiffness of soil. In this paper, we proposed an equation which produces the ultimate lateral resistance of the laterally loaded single pile in sand using the strain wedge model of the soil deformation. The ultimate lateral resistance in strain wedge model is composed of earth pressure of wedge rear, the shear resistance on the side of the wedge, and the frictional resistance between pile and ground. The ultimate lateral resistance determined by the proposed equation was compared with the Ashour, F.D.M., field test in sand. As a result, the error of the proposed equation and Ashour theory, field test, F.D.M were respectively 1.03%, 0.40~3.32%, 6.02%.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.932-939
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• 2005

Recently, the lateral displacement of the passive piles which installed under the revetment on soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of the ground when the revetment loading is exceeded a certain limit. The lateral displacement of ground causes an excessive deformation of under structure itself and develops lateral earth pressure against the pile foundation as well. Especially passive piles subjected to lateral earth pressures are likely to have excessive horizontal displacement and large bending moment, which induces structural failure of pile foundation and harmful effects on superstructure. The subject of study is to investigate the later displacement of pile foundation during the construction of container terminal at the south port of Incheon. Actual field measurement data and finite element method(FEM) by AFFIMEX Ver 3.4 were used to analyze the displacement of pile and the vertical settlement of soft ground. This analysis was carried out at each sequence of construction work.

• Journal of Rhinology
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• v.25 no.2
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• pp.99-102
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• 2018

Lateral pharyngoplasty is a surgical option for treatment of obstructive sleep apnea (OSA). Here, we present a case involving a 40-year-old healthy man who underwent surgery, including lateral pharyngoplasty and robotic tongue base resection, for OSA. There were no intraoperative or immediate postoperative complications. However, on postoperative day 3, the patient presented with swelling in the temporal and buccal areas and was diagnosed with subcutaneous emphysema, later confirmed by computed tomography. The patient was carefully monitored under conservative care and discharged without complications. Although subcutaneous emphysema following tonsillectomy is a rare complication and usually resolves with conservative management, in certain cases, it might require surgical intervention. Lateral pharyngoplasty involves tonsillectomy and additional incision along the tonsillar fossa, which makes it susceptible to pharyngeal wall defects and, consequently, subcutaneous emphysema. Additionally, lateral pharyngoplasty and robotic tongue base resection cause pain and might thus contribute to the increase in intrapharyngeal pressure, which might aggravate subcutaneous emphysema. Lateral pharyngoplasty should be performed with meticulous dissection of the superior pharyngeal constrictor muscle. Healthcare providers should be aware of these complications and, upon suspicion of the same, place the patient under close observation to prevent life-threatening situations.

• Physical Therapy Korea
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• v.22 no.2
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• pp.41-51
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• 2015

The purposes of this study were 1) to determine the effects of low-dye taping on peak plantar pressure following treadmill walking exercise, 2) to determine whether the biomechanical effectiveness of low-dye taping in peak plantar pressure was still maintained following removal of the tape during treadmill walking, and 3) to determine the trend towards a medial-to-lateral shift in peak plantar pressure in the midfoot region before and after application of low-dye taping. Twenty subjects with flexible flatfoot were recruited using a navicular drop test. The peak plantar pressure data were recorded during five treadmill walking sessions: (1) un-taped, (2) baseline-taped, (3) after a 10-minute treadmill walking exercise, (4) after a 20-minute treadmill walking exercise, and (5) after removal of the taping. The foot was divided into six parts during the data analysis. One-way repeated measures analysis of variance was performed to investigate peak plantar pressure variations in the six foot parts in the five sessions. This study resulted in significantly increased medial forefoot peak plantar pressure compared to the un-taped condition (p=.017, post 10-minute treadmill walking exercise) and (p=.021, post 20-minute treadmill walking exercise). The peak plantar pressure in the lateral forefoot showed that there was a significant decrease after sessions of baseline-taped (p=.006) and 10-minute of treadmill walking exercise (p=.46) compared to the un-taped condition. The tape removal values were similar to the un-taped values in the five sessions. Thus, the findings of the current study may be helpful when researchers and clinicians estimate single taping effects or consider how frequently taping should be replaced for therapeutic purposes. Further studies are required to investigate the evidence in support of biomechanical effectiveness of low-dye taping in the midfoot region.

• Structural Engineering and Mechanics
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• v.48 no.3
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• pp.367-382
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• 2013

Different types of long slender pile shall buckle with weak soil and liquefied stratum surrounded. Different from considering single side earth pressure, it was suggested that the lateral earth pressure can be divided into two categories while buckling: the earth pressure that prevent and promotes the lateral movement. Active and passive earth pressure calculation model was proposed supposing earth pressure changed linearly with displacement considering overlying load, shaft resistance, earth pressure at both sides of the pile. Critical buckling load calculation method was proposed based on the principle of minimum potential energy quoting the earth pressure calculation model. The calculation result was contrasted with the field test result of small diameter TC pile (Plastic Tube Cast-in-place pile). The fix form could be fixed-hinged in the actual calculation assuring the accuracy and certain safety factor. The contributions of pile fix form depend on the pile length for the same geological conditions. There exists critical friction value in specific geological conditions that the side friction has larger impact on the critical buckling load while it is less than the value and has less impact with larger value. The buckling load was not simply changed linearly with friction. The buckling load decreases with increased limit active displacement and the load tend to be constant with larger active displacement value; the critical buckling load will be the same for different fix form for the small values.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.3
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• pp.149-154
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• 2002

The blood pressure (BP) is regulated by the nervous system and humoral factors, such as renin- angiotensin system, vasopressin and others. In the present study, we examined the central effects of glutamate and GABA on the cardiovascular regulation by injection of these substances into the lateral ventricle and also investigated the relationship between these central effects and the action of angiotensin II (Ang). Male Sprague Dawley rats, $350{\sim}400$ g, were anesthetized with urethane and instrumented with an arterial catheter for direct measurement of BP and heart rate (HR), and an guide cannula in the lateral ventricle for drug injection. A glass microelectode was inserted into the rostral ventrolateral medulla (RVLM) for recording single unit spikes. Barosensitive neurons were identified by changes of single unit spikes in RVLM following intravenous injection of nitroprusside and phenylephrine. The effects of GABA and glutamate injected into the lateral ventricle were studied in single neuronal activity of the RVLM in addition to changes in BP and heart rate, and compared the results before and after treatment with intravenous losartan, nonpeptide Ang II-type 1 receptor antagonist (1 mg/100 g BW). Intracerebroventricular administration of GABA decreased systolic blood pressure (SBP) and HR, but increased the firing rates in the RVLM. However, intracerebroventricular glutamate injection produced effects opposite to GABA. After pretreatment of intravenous losartan, the central effects of GABA on BP and firing rate in the RVLM were significantly attenuated and that of glutamate showed a tendency of attenuation. These results suggested that central GABA and glutamate regulated BP and firing rates in RVLM were inversely related to BP change. The central effects of GABA or glutamate on the autonomic nervous function were modulated by humoral factor, Ang II, by maintaining BP.

• The Journal of Korean Physical Therapy
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• v.12 no.3
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• pp.455-467
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• 2000

The purpose of this study was to analyse the effects of disc degeneration on the biomechanical behaviors of the intervertebral disc in term of axial displacement, intradiscal pressure. disc bulge at the 1.4-1.5 functional spinal unit(FSU). The degeneration is divided 4 grade by initial intradiscal pressure: normal: 135kPa. mild: 107kPa. moderate: 47kPa, severe: 15kPa, The predicted results were follows: 1. The magnitude of the bulge is found to be maximum at the anterior, minimum at the postero-lateral portion. The bulge of lateral, postero-lateral is found to be maximum in severe grade. followed by moderate. mild, normal grade. 2. Tho displacement was increased with increasing compressive load in all four grades.'rho stiffness of disc was found to be reduced by progressing from normal to severe grade. 3. The intradiscal pressure was increased nearly linearly with increasing compressive load in normal and mild grade. But the increasing rate in moderate and severe grade was showed apparently different from nomal and mild grade. Specially, it was increased very slightly in severe grade. In conclusion, decreased intradiscal pressure resulted in increase of axial displacement and disc bulge with compressive load increasing. these may compromise the nerve root impingement or irritation. Therefore posture and activities must be focus to reduce compressive load applied on the back or disc.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.43-53
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• 2006

Among several movements that occurred upon a slope, golf swing is the most typical one because environmental conditions dynamically vary with many kinds of slopes. Some studies on the golf swing were performed about a weight transfer on flatland, however, there couldn't be seen any study about the weight transfer on slope elsewhere. Therefore, the purpose of this study was to provide quantified data to objectively test the coaching words and keys about the weight transfer at sidehill slope during goal impact EspeciaIly sidehill Slopes with ball above the feet. Four highschool golfer, who have average handy 5, were recruited for this study. Plantar pressure distribution and cinematographic data were collected during golf swing in the conditions of flatland, $5^{\circ}$, $10^{\circ}$ and $15^{\circ}$sidehill slope simultaneously. The two data were used to synchronize the two data later. The plantar regions under the foot were divided into 8 regions according to the directly applied pressure pattern of the subject to insole sensor. The 8 foot regions were hullux, medial forefoot, central forefoot, lateral forefoot, medial midfoot, lateral midfoot, medial heel, and lateral heel. And the plantar pressure data was also divided into four movement address, phases-backswing. downswing, and follow-through phases according to the percentage shown to the visual information of film data. Based on the investigations on public golf books and experiences of golfers, it was hypothesized by the authors in the early of this study that the steeper slopes are, the more weight loads on left foot that positions at the higher place. When observing the results of plantar pressure and vertical force curves according to the sidehill slope conditions, the hypothesis could be accepted.

• Korean Journal of Applied Biomechanics
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• v.31 no.2
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• pp.104-112
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• 2021

Objective: This study aimed to analyze the effects of consecutive whole body vibration through heel raise posture on the center of pressure and electromyography of anterior tibial muscle, lateral gastrocnemius and soleus muscles during single-leg stance. Method: The subjects of this study included 30 healthy males in their 20's, with the following inclusion criteria: no history of orthopaedic medical history, no participation in regular exercises, no history of whole body vibration exercise, and right leg being the dominant leg. The experimental procedure involved pretreatment measurement of eye open single-leg stance, application of whole body vibration for 30 seconds, post-treatment measurement (3 measurements in total). Static and dynamic movements have been measured over 2 separate experiments, with 72 hours gap between the experiments. Static movement involved maintaining single-leg heel raise posture for 30 seconds while applying whole body vibration, and dynamic movement involved heel raise (15 repetitions over 30 seconds) while applying whole body vibration. The strength of applied whole body vibration was 35 Hz frequency and 2~4 mm amplitude. Results: As the single-leg posture after static heel raise posture, mediolateral velocity of the center of pressure at post 2 and post 3 were significantly reduced compared to the pre-treatment measurement. In addition, the percentage for reference voluntary contraction in anterior tibial muscle and soleus and median frequency at anterior tibial muscle and lateral gastrocnemius muscle at post 3 were significantly decreased compared to the pre-treatment value. As the single-leg posture after dynamic heel raise posture, the mediolateral 95% edge frequency of the center of pressure and median frequency at anterior tibial muscle, lateral gastrocnemius muscle, and soleus muscle at post 3 were significantly reduced compared to the pre-treatment value. Conclusion: Acute whole body vibration via static and dynamic heel raise posture have positive effect on mediolateral posture control during single-leg stance.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.67-74
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• 2012

The arching effect of the active earth pressure acting on an excavation wall subjected to close excavation reduces lateral earth pressure acting on excavation wall. In this paper, the arching effect was estimated for varying width to excavation depth ratio and wall friction angle by analytical and numerical methods verified with centrifuge test results. The arching effect is significant when the width to excavation depth ratio and wall friction angle is decreased and increased, respectively. The analytical solution derived from the classical arching theory suggested by Handy(1985) shows good agreement with the numerical solution than the other solutions.