• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.779-788
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• 2019

The compaction grouting method is one of the conventional ground improvement methods, which consolidates and compacts the surrounding ground through the injection of grout materials with low mobility. Injecting the grout into the ground can improve the soil properties, as well as form a composite of soil-grout columns. However, the conventional grout pumping is not applicable to handle multiple injection holes at the same time, which may diminish its constructability when the construction time is not enough. This paper proposes a simultaneous multiple compaction-grouting method using a new pump system developed to cover up simultaneously three injection holes at a time. Field injection tests with a single injection hole and with triangular arrangement of injection holes were conducted to evaluate the applicability of the proposed method to soft clay ground. In addition, a series of standard penetration tests (SPTs) were performed to assess the efficiency of each arrangement in improving the soft ground. It is noted from the in-situ test results that the interval distances between injection holes and the elapse time for ground stabilization are the crucial factors governing the applicability of the simultaneous multiple compaction-grouting method to improve the soft clay ground.

• Korean Journal of Applied Biomechanics
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• v.25 no.1
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• pp.131-140
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• 2015

Purpose : The purpose of this study was to analyze the coordination of the trunk tilting angle and bilateral lower limbs according to the stirrups length during trot in equestrian. Methods : Participants selected as subject were consisted of adult male(n=7, mean age: $45.00{\pm}3.78yrs$, mean height: $172.50{\pm}2.44cm$, mean body mass: $76.95{\pm}4.40kg$, mean, mean leg length: $97.30{\pm}2.60cm$). They were divided into 3-types of stirrups lengths(67 cm, 72 cm, 77 cm) during trot. The variables analyzed were consisted of the trunk front-rear angle, lower limb joint(Right Left hip, knee, ankle), overall movement index(OMI) of the lower limbs(thigh, shank, foot) and asymmetry index(AI%) during trot. Results : The average angle in hip and knee joint showed more extended posture according to the increase of stirrups lengths and ankle angle showed more plantarflexion posture according to increase of stirrups length during 1 stride in trot. Also, average angle showed more extended posture in right hip and ankle joint than that of left. The angle of knee joint didn't show significant difference statistically between right and left. Also asymmetric index in average angle of hip, knee and ankle joint didn't show significant difference statistically in between lower limbs, but hip joint showed higher asymmetric index in stirrup length of 77 cm and ankle joint showed higher asymmetric index in stirrup length of 67 cm than that of the others respectively. The FR angle in trunk of horse-rider showed relative backward leaning motions at stirrup length of 67 cm and 77 cm than that of stirrup length of 72 cm during stance and swing phase. OMI in thigh, shank, and foot limbs didn't show significant difference statistically according to the stirrups length of right and left lower limbs, but left lower limbs showed higher index than that of right lower limb. Stirrup length of 72 cm in shank and foot limbs showed higher index than that of stirrup length of 67 cm and 77 cm. But stirrup length of 72 cm showed higher asymmetric index than that of stirrups length of 67 cm and 77 cm. Conclusions : When considering the above, 72 cm(ratio of lower limb 74.04%) stirrup lengths could be useful in posture correction and stabilization than 67cm(ratio of lower limb 68.69%) and 77 cm(ratio of lower limb 79.18%) stirrup lengths during trot in horse back riding.

• Geotechnical Engineering
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• v.7 no.4
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• pp.49-64
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• 1991

Abstract The stabilization by lime or Portland cement has long been the most commonly used methods for clay soil. But it wart the purpose of this reserch to define the effectiveness malt content on unconfined compressive strength of limeflay mixture and cementrlay mixture. From result of a laboratary investigation, saInt content in sample soil was not concernd with variation of PH value. PH value of lime 10% mixture and of cement 10% mixture were near 12.4, 11.6 respectively. In case of more than 7 curing days, PH value and Ca++ion concentration were decreased with increasing curing time. Also the result of X-ray difflection analysib for stabilized soil by admixture 10% in 90 curing days showed that the diffrection intensity of Tobermorite and Ettringite and other reaction products was smaller in the case of addition of salt 8% than malt 0% in stabilized soil. When lime-soil mixture and cement-boil mixture were cured in 2$0^{\circ}C$ and 5$^{\circ}C$, 2$0^{\circ}C$ cured mizture produced significantly higher compressive strength than 5t cured mixture and air dry curing sample produced higher than cured sample in water. The addition of salt 2~4% in conjuntion with lime or cement may accelerate strenth gain or not prevent front However, the addition of salt 8% prevent from strength gams.

• The Korean Journal of Financial Management
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• v.20 no.2
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• pp.73-94
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• 2003

In general, the interest rate is forecasted by the parametric method which assumes the interest rate follows a certain distribution. However the method has a shortcoming that forecasting ability would decline when the interest rate does not follow the assumed distribution for the stochastic behavior of interest rate. Therefore, the nonparametric method which assumes no particular distribution is regarded as a superior one. This paper compares the interest rate forecasting ability between the two method for the Monetary Stabilization Bond (MSB) market in Korea. The daily and weekly data of the MSB are used during the period of August 9th 1999 to February 7th 2003. In the parametric method, the drift term of the interest rate process shows the linearity while the diffusion term presents non-linear decline. Meanwhile in the nonparametric method, both drift and diffusion terms show the radical change with nonlinearity. The parametric and nonparametric methods present a significant difference in the market price of interest rate risk. This means in forecasting the interest rate and the market price of interest rate risk, the nonparametric method is more appropriate than the parametric method.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.712-716
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• 2010

Purpose: Extensive lumbosacral defects after removal of spinal tumors have a high risk of wound healing problems. Therefore it is an effective reconstructive strategy to provide preemptive soft tissue coverage at the time of initial spinal surgery, especially when there is an instrument exposure. For soft tissue reconstruction of a lumbosacral defect, a variation of the gluteal flap is the first-line choice. However, the musculocutaneous flap or muscle flap that is conventionally used, has many disadvantages. It damages gluteus muscle and causes functional disturbance in ambulation, has a short pedicle which limits areas of coverage, and can damage perforators, limiting further surgery that is usually necessary in spinal tumor patients. In this article, we present the superior gluteal artery perforator turn-over flap that reconstructs complex lumbosacral defects successfully, especially one that has instrument exposure, without damaging the ambulatory function of the patient. Methods: A 67 year old man presented with sacral sarcoma. Sacralectomy with L5 corpectomy was performed and resulted in a $15{\times}8\;cm$ sized complex soft tissue defect in the lumbosacral area. There was no defect in the skin. Sacral stabilization with alloplastic fibular bone graft and reconstruction plate was done and the instruments were exposed through the wound. A $18{\times}8\;cm$ sized superior gluteal artery perforator flap was designed based on the superior gluteal artery perforator and deepithelized. It was turned over 180 degrees into the lumbosacral dead space. Soft tissue from both sides of the wound was approximated over the flap and this provided in double padding over the instrument. Results: No complications such as hematoma, flap necrosis, or infection occurred. Until three months after the resection, functional disturbances in walking were not observed. The postoperative magnetic resonance imaging scan shows the flap volume was well maintained over the instrument. Conclusion: This superior gluteal artery perforator turn-over flap, a modification of the conventional superior gluteal artery perforator flap, is a simple method that enabled the successful reconstruction of a lumbosacral defect with instrument exposure without affecting ambulatory function.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.194-200
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• 2005

Purpose: To evaluate the short-term follow up outcome and the effectiveness of arthroscopic vertical shift of anteroinferior capsulolabral complex, plication of AIGHLC (anterior band of inferior glenohumeral ligament complex) and thermal capulorraphy, posteroinferior suture plication, rotator interval closure as an adjuncts in recurrent instability of megafrequency with night time dislocation. Materials & Methods: From March 1998 to February 2004, we have had 18 shoulders out of 156. All of the cases have been night time dislocation above more one time. The age were average 29.4$(21{\sim}37)$ year old. The average follow up were 21.1 $(12{\sim}45)$months We checked Rowe score and ROM at pre-operation, post-operation 6 months,1 year & last follow up period. Results: Above good results were 16 cases(88.9%). The excellent were 6 cases, good were 10, fair 1, poor 1. Conclusions: In recurrent anterior shoulder dislocation in greater than 50 frequency, arthroscopic stabilization can be an alternative technique for selected patients against open inferior capsular shift. But more long ter n follow up and large materials will be needed in the future study.

• Neonatal Medicine
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• v.16 no.1
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• pp.64-70
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• 2009

Congenital diaphragmatic hernia (CDR) with severe pulmonary hypoplasia is associated with significant mortality. Recently, several new therapeutic methods have been suggested, such as high-frequency oscillatory ventilation and inhaled nitric oxide. For hypoxemic respiratory failure unresponsive to these advanced medical treatment options, extracorporeal membrane oxygenation (ECMO) serves as the last potentially effective treatment. An understanding of the pathophysiology of pulmonary hypertension associated with CDH led to a strategy involving preoperative stabilization and delayed surgical intervention with ECMO. We describe four cases of ECMO, including the first report of ECMO for neonatal CDH in Korea.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.717-726
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• 2007

Objectives : This study was conducted to assess the effect of Uhwangchungsimwon on the autonomic nervous system. Methods : Eligible subjects were enrolled from healthy people in their 20s-30s. They were divided into two groups, the UC group (n=22) and the control group (n=20). We monitored ECG from 14:00 to 18:00 in both groups. In the UC group, subjects were administered UC at 15:00. HRV analysis was conducted at 14:00, 16:00, and 17:00 for 512 seconds. Results : The degree of LF/HF ratio change was significantly higher in the UC group at 1 hour after administration. Conclusion : We suggest Uhwangchungsimwon may be useful for stabilization of the autonomic nervous system by activating parasympathetic nerve in healthy people.

• The Journal of Engineering Geology
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• v.25 no.1
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• pp.115-129
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• 2015

The cut-slope of a large-sectional tunnel portal is recognized as a potential area of weakness due to unstable stress distribution and possible permanent displacement. This paper presents a case study of a slope failure and remediation for a large-scale cut-slope at a tunnel portal. Extensive rock-slope brittle failure occurred along discontinuities in the rock mass after 46 mm of rainfall, which caused instability of the upper part of the cut-slope. Based on a geological survey and face mapping, the reason for failure is believed to be the presence of thin clay fill in discontinuities in the weathered rock mass and consequent saturationinduced joint weakening. The granite-gneiss rock mass has a high content of alkali-feldspar, indicating a vulnerability to weathering. Immediately before the slope failure, a sharp increase in displacement rate was indicated by settlement-time histories, and this observation can contribute to the safety management criteria for slope stability. In this case study, emergency remediation was performed to prevent further hazard and to facilitate reconstruction, and counterweight fill and concrete filling of voids were successfully applied. For ultimate remediation, the grid anchor-blocks were used for slope stabilization, and additional rock bolts and grouting were applied inside the tunnel. Limit-equilibrium slope stability analysis and analyses of strereographic projections confirmed the instability of the original slope and the effectiveness of reinforcing methods. After the application of reinforcing measures, instrumental monitoring indicated that the slope and the tunnel remained stable. This case study is expected to serve as a valuable reference for similar engineering cases of large-sectional slope stability.

• Clinics in Shoulder and Elbow
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• v.13 no.1
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• pp.47-52
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• 2010

Purpose: To evaluate shoulder stability, clinical, and functional results more than 6 months after utilizing the 'Remplissage' technique, consisting of an arthroscopic posterior capsulodesis and infraspinatus tenodesis, to fill Hill-Sachs lesions. Materials and Methods: Seven patients were followed-up more than 6 months after the 'Remplissage' procedures performed in our hospital from August 2008 to August 2009. The mean age of the patients was 28.6 years and the mean follow-up time was 10 months. Evaluations included ROM, ASES score, KSSI score, ROWE score, and postoperative MRI. Results: In a functional evaluation of the patients with an average postoperative time of 10 months, the ASES score improved from 51.4 preoperatively to 76.8 postoperatively, the KSSI score improved from 46.5 preoperatively to 76 postoperatively, and the ROWE score improved from 43.5 preoperatively to 76.3 postoperatively. After an average postoperative time of 10 months, the range of motion was nearly normal (>170 degrees in further flexion, and >45 degrees in external rotation). Conclusion: In recurrent shoulder instabilities with large Hill-Sachs lesions, the 'Remplissage' technique resulted in good outcomes in terms of shoulder stability, clinical, and functional results after postoperative times of more than 6 months.