• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.1 s.24
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• pp.29-38
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• 2007

The research on the track performance and stability of the tilting-train was performed and the settlement of the roadbed was estimated as the tilting train was being operated on the rail joint under the allowable velocity subjected to the track performance and the stability of the tilting-train. Since the impact on the continuous welded rail (CWR) induced by the tilting-train loading is different from the impact on the rail joint, it needs to investigate the settlement of the roadbed beneath the CWR. In this study, when the tilting-train is being operated on the CWR under the allowable velocity subjected to the track performance and the stability of the tilting-train, the settlement and bearing capacity of the roadbed beneath the CWR have been evaluated using numerical analysis and compared with those beneath the rail joint. The numerical results show that the settlements of the roadbed beneath CWR and rail joint are amount to 71.2% and 88.8% of the allowable settlement, respectively. And the stresses are amount to 10.4% and 12.1% of the allowable bearing capacity, respectively.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.465-477
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• 2018

The purpose of this study is to analyze the effect of three - week high altitude ski training on the myocardial performance of cross - country skiers and to provide basic data for the future improvement of cross - country skiers'. The subjects were 6 cross - country skiing male college athletes. To investigate the effects of periodic and high altitude training on cross - country skiers, a general linear model ANOVA with repeated measure And analyzed using the Paired Samples t-test. In high altitude ski training for 3 weeks, the body composition did not change but the isokinetic muscular function of the shoulder joint, hip joint, knee joint, and ankle joint was decreased. Therefore, further study is needed if it is considered that continuous strength training should be performed during the ski training period such as SP period.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.2
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• pp.169-172
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• 2019

Frequency-modulated continuous wave(FMCW) radars with array antennas are widely used because of their light weight and relatively high resolution. A usual approach for the joint range and angle estimation of a target using an array FMCW radar is to create a range-angle matrix with the deramped received signal, and subsequently apply two-dimensional(2D) frequency estimation methods such as 2D fast Fourier transform on the range-angle matrix. However, such frequency estimation approaches cause bias errors since the frequencies in the range-angle matrix are not independent. Therefore, we propose a new maximum likelihood-based algorithm for joint range and angle estimation of targets using array FMCW radar, and demonstrate that the proposed algorithm achieves the Cram?r-Rao bounds, both for range as well as angle estimation.

• Steel and Composite Structures
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• v.37 no.3
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• pp.307-321
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• 2020

The slim-floor solution provides an efficient alternative to the classic slab-over-beam configuration due to architectural and structural benefits. Two deficiencies can be identified in the current state-of-art: (i) the technique is limited to nonseismic applications and (ii) the lack of information on moment-resisting slim-floor beam-to-column joints. In the seismic design of framed structures, continuous beam-to-column joints are required for plastic hinges to form at the ends of the beams. The present paper proposes a slim-floor technical solution capable of expanding the current application of slim-floor joints to seismic-resistant composite construction. The proposed solution relies on a moment-resisting connection with a thick end-plate and large-diameter bolts, which are used to fulfill the required strength and stiffness characteristics of continuous connections, while maintaining a reduced height of the configuration. Considering the proposed novel solution and the variety of parameters that could affect the behavior of the joint, experimental and numerical validations are compulsory. Consequently, the current paper presents the experimental and numerical investigation of two slim-floor beam-to-column joint assemblies. The results are discussed in terms of moment-rotation curves, available rotational capacity and failure modes. The study focuses on developing reliable slim-floor beam joints that are applicable to steel building frame structures located in seismic regions.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.833-841
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• 2008

Recently, the upheaval generation in the road which is under service had been reported. Due to the upheaval generation, total 4 lanes were forced to curtail to 3 lanes, and traffic was delayed. In normal situation of cut-slopes in korea, that condition is hard to detect since most cut-slopes contain discontinuous material, that is rock. Common collapses in rock-slopes is wedge failure, plane failure and toppling failure which is all individual mechanism of discontinuous rock mass. In contrast, such upheaval in the road in front of cut-slope can be generated only when circular movement is triggered within the cut-slope. In this sense, rock-slopes barely show any kind of movement in the road locates at the front of them. Numerical analysis is general method in simulation of slope displacement and evaluation of safety. However, numerical analysis programs which are related with rock-slopes are not able to simulate such upheaval movement because that programs are based on discontinuous modeling mechanism. In addition, although numerical analysis programs which are based on FEM/FDM and thus utilize continuous modeling mechanism are able to simulate circular movement and upheaval situation, they have weakness in reflecting discontinuities of rock-slope itself. In this study, detailed in-site investigation and numerical analysis based on in-site condition were performed in order to expect upheaval movement in the road. In this procedure, the FLAC program which uses continuous modeling method was utilized, and new approach reflecting discontinuity developed toward the road with a ubiquitous joint model was tried to derive reliable analysis result.

• Composites Research
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• v.16 no.6
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• pp.16-22
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• 2003

This paper studied the AE(acoustic emission) characteristics of the laminated composite structures. The composite stiffened panels under the compressive loading emitted various AE signals when they buckled or changed the buckling modes. In addition, the failure initiated and propagation generated a lot of complex signals. From the continuous signal generation. we identified when the failures initiated and whether they propagated or not. The single lap joint of laminated plates under tensional load also generated AE signals when bonding region failed. The first failure occurrence and its propagation are monitored by generated AE signals. The characteristics of AE signals used in this analysis are cumulative hits, hit distribution, peak frequency of generated AE waveform and amplitude of signals. The analysis of AE signals shows that continuous increment of cumulative hits can be regarded as damage propagation and three dominant peak frequencies can correspond to typical failure modes in the laminated composites.

• Journal of muscle and joint health
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• v.23 no.2
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• pp.84-94
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• 2016

Purpose: This research aimed to identify levels of nurses' perception and practice of fluid intake and output (I & O) measurement and to explore the relationship between perception and practice of it. Methods: Using a cross-sectional survey design, 195 nurses who practiced fluid I & O measurement were recruited from a general hospital. Nurses who agreed to participate in this study completed a structured study questionnaire to assess their levels of perception and practice of fluid I & O measurement. Results: A level of perception of I & O measurement was high (3.46 points out of 5), and scores for 3 subdomains of I & O (importance, accuracy, and efficacy) were evenly high. The level of practice of I & O was fairly high (3.76 points out of 5). Perception and practice of I & O were highly correlated (r=.73, p<.001). Conclusion: Nurses seem to have higher levels of perception and do practice fluid I & O measurement correctly. In order to have reliable and valid I & O measures, nurses need to have continuous education on I & O measurement based on clinical guideline to utilize it as an invaluable clinical instrument.

• Journal of Korean Foot and Ankle Society
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• v.1 no.1
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• pp.23-29
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• 1997

Freiberg's disease is a pathologic condition of the second or third metatarsal head, rarely the forth or fifth metatarsal head, and it becomes abnormally enlarge due to avascular necrosis of subchondral cancellous bone. From Nov. 1982 to Sep. 1994, we treated surgically 10 cases of the disease who complained the continuous symptoms inspite of proper conservative management. Metatarsal head excision was done in 8 cases and resurfacing of the cartilagenous portion of the metatarsal head in 2 cases. During the average follow up of 55 months, the pain was relieved in all patients who were underwent surgical intervention but the stiffness of the metatarsophalangeal joint was remained in most of cases. It seems to be a logical treatment of choice in younger and active patients that conservative management is the initial treatment but more ablative procedure is needed for the continued symptoms. We can propose the metatarsal head excision or resurfacing of the involved joint is effective treatment method with simple procedure and minimize morbid period than other procedures such as corrective osteotomy.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.1
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• pp.60-67
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• 1995

It is difficult to manage the growing deformity of forearm bone caused by hereditary osteochondromatosis in children, because deformity and discrepancy of limb length is progressive. The are many treatment methods of these problems including excisio of osteochondroma, lengthening of ulna, shortening of radius, corrective osteotomy with or without lengthening apparatus. Among many treatment methods, we tried free vascularized epiphyseal transplantation with the proximal fibular epiphysis in 3 patients of hereditary osteochondromatosis for inducement of continuous bone growth and deformity correction. The average duration of follow up was 7 years and 1 month, the shortest duration being to 4 years and 5 months and the longest 10 years and 8 months. Serial radiologic and clinical evaluation were carried out during follow up and there were satisfactory length gain, deformity correction and improvement of adjacent joint motion in 2 cases. According to our follow up evaluation, free vascularized epiphyseal transplantation is valuable procedure in forearm deformity of hereditary osteochondromatosis although it needs skillful and experienced operative technique.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.1
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• pp.35-40
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• 2013

Osteochondroma is a common benign tumor of the axial skeleton, especially in the distal metaphysis of the femur and the proximal metaphysis of the tibia, that can occur on the facial skeleton (albeit rarely). Osteochondroma is differentiated from chondroma, osteochondromatosis and osteoma. Osteochondroma shows an irregular radiopaque lesion and chondromatic area surrounded by the osteoma. When it develops in the long bone, it has a marked tendency to occur at 10 to 20 years of age and ceases with the end of pubertal growth. However, when it develops in the mandibular condyle, it is prevalent in the third decade and continuous to develop. Tumors that develop in the long bone have a predilection for men, but tumors in the mandible have a predilection for women. In osteochondroma of the mandibular condyle, clinical features presented include occlusal changes, facial asymmetry, headaches, pain and joint noise on the temporomandibular joint, mouth opening limitations, and jaw deviation at the involved site. The first choice of treatment for the massive osteochondroma is surgical removal. A 70-year-old female patient with an osteochondroma on her right mandibular condyle visited our clinic. We surgically removed the mass with favorable results. It is presented here along with a review of literature on osteochondroma.