• Tunnel and Underground Space
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• v.19 no.3
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• pp.236-247
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• 2009

Overpopulation has significantly increased the use of underground spaces in urban areas, and led to the developments of shallow-depth underground space. Due to unexpected rock fall, however, it is very necessary to understand and categorize the rock mass behaviors prior to the tunnel excavation, by which unnecessary casualties and economic loss could be prevented. In case of cave-in, special attention should be drawn since it occurs faster and greater in magnitude compared to rock fall and plastic deformation. Types of cave-in behavior are explained and categorized using seven parameters - Uniaxial Compressive Strength (UCS), Rock Quality Designation (RQD), joint surface condition, in-situ stress condition, ground water condition, earthquake & ground vibration, tunnel span. This study eventually introduces a new index called Cave-in Behavior Index (CBI) which explains the behavior of cave-in under given in-situ conditions expressed by the seven parameters. In order to assess the mutual interactions of the seven parameters and to evaluate the weighting factors for all the interactions, survey data of the experts' opinions and Rock Engineering Systems (RES) were used due to lack of field observations. CBI was applied to the tunnel site of Seoul Metro Line No. 9. UDEC analyses on 288 cases were done and occurrences of cave-in in every simulation were examined. Analyses on the results of 288 cases of simulations revealed that the average CBI for the cases when cave-in for different patterns of tunnel support was estimated by a logistic regression analysis.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.133-144
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• 1995

After resection of intraarticular, periacetabulum(P2) and pubic rami(P23) and extraarticular, proximal femur(P2-H12) by Enneking classification, reconstruction is very difficult. We experienced three cases of saddle prostheses for reconstruction after P2, P23, and P2-H12 resection in pelvic malignancies. Case 1 was a high grade chondrosarcoma in 36 year-old-man and P2 resection was done. But he died of disease 19 months after operation. Case 2 was a malignant giant cell tumor in 32 year-old-woman. P23 resection was given and she is disease-free 32 months after operation. Case 3 was an osteosarcoma of 27-year-old-man and P2-H12 resection was performed and he is disease-free postoperative 12 months now. According to MSTS functional evaluatin system, all three patients showed no pain(5), intermediate function(2), emotinally satisfied(3), one cane or crutch supported(1), limited walking(3), and minor cosmetic gait(3). There was no significant complication and no dislocation except intermittent inguinal hernia in case 2. All patients started crutch walking 3 weeks after operation. Around 6 months postoperatively, the preserved iliac wing(P1 component) was hypertrophied enough to endure the full weight bearing. All could have squating and kneeling positions. In conclusion, saddle prosthesis would be a very useful method of reconstruction after P2, P23, and/or H1-2 resection to shorten the operation time and to reduce the infection rate without significant loss of function.

• Clinics in Shoulder and Elbow
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• v.10 no.1
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• pp.33-41
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• 2007

Purpose: The purpose of this study was to prove the effectiveness of the open medial (glenoid-based) anterior-inferior capsular shift in patients with multidirectional shoulder instability. Materials and Methods: We reviewed 19 patients treated by medial anterior-inferior capsular shift for multidirectional shoulder instability from March, 1998 to December, 2003. 15 patients of them have experienced recurrent dislocation. 8 patients(42%) showed bilateral laxity and 11 patients(58%) generalized ligamentous laxity, and 2 patients(10.5%) voluntary subluxation. An average follow-up was 24 months (range : $9{\sim}32$ months). Results: Pain improved in 18 patients of all. There was an average loss of 10 degree of external rotation, but no limitation of activity of daily living. There was no redislocation and subluxation, but two patients had some apprehension in sports activity. With Rowe score, the result was excellent or good in all patients. There were hematoma and local skin problem in 1 patient, but all had healed up. Conclusion: Medial anterior-inferior capsular shift in multidirectional shoulder instability provided satisfactory results in pain relief, patient's satisfactions and stability of glenohumeral joint. Though some of them have anterior gleniod deformities and large Hill-Sachs lesions, we could get good stabilities.

• Korean Security Journal
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• no.49
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• pp.187-214
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• 2016

In the mordern society, the reliance on the cyber domain and the cyber connectivity has been increasingly strengthened. Due to this phenomenon, the cyberterror against critical infrastructures and state organs might lead to fatal consequences. Lately, North Korea's cyberattacks against South Korea's national organizations and financial computer networks are becoming more and more intelligent and sophisticated. The cyberattacks against such critical infrastructures have caused enormous economic loss and social disorder. This paper is designed to examine comparatively the cyberterror related laws and organizations of the advanced countries such as U.S. and U.K. and to draw implications. Although those countries are under different institutional and cultural backgrounds with varying security envrionments, they are identically pursuing measures by establishing government-wide counterterror system for coordination and cooperation. They are also commonly focusing upon creating new organizations equipped with new system and upon enhancing intelligence performance and devising punishment regulations. Korea is lack of framework laws regulating cyber security, having only scattered individual laws. Since such legal base is far from efficient counterterror activities, it is necessary that the legal and policy response of the advanced countries should be closely studied for selective introduction. That will eventually lead to legislation of cyber security law. With such legislation on hand, it is subsequently required to strengthen crisis management for prevention of cyberterror and to create joint response team, cooperating with private organizations.

• The Journal of the Acoustical Society of Korea
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• v.34 no.6
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• pp.411-422
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• 2015

This paper presents an overview of the geological environment investigation and underwater acoustic measurements for the purpose of "Study on the Relationship between the Geological Environment and Acoustic Propagation in Shallow Water", which are jointly carried out by KIOST (Korea Institute of Ocean Science & Technology) and Hanyang University in the western shallow water off the Taean peninsula in the Yellow Sea in April-May 2013. The experimental site was made up of various sediment types and bedforms due to the strong tidal currents and coastal geomorphological characteristics. The geological characteristics of the study area were intensively investigated using multi-beam echo sounder, sub-bottom profiler, sparker system and grab sampler. Acoustic measurements with a wide range of research topics in a frequency range of 20~16,000 Hz: 1) low frequency sound propagation, 2) mid-frequency bottom loss, 3) spatial coherence analysis of ambient noise, and 4) mid- frequency bottom backscattering were performed using low- and mid-frequency sound sources and vertical line array. This paper summarizes the topics that motivated the experiment, methodologies of the acoustic measurements, and acoustic data analysis based on the measured geological characteristics, and describes summary results of the geological, meteorological, and oceanographic conditions found during the experiments.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.2 no.1
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• pp.39-44
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• 2006

Cerebral palsy(CP) is one of the most common motor disease, due to brain injury during fetal and neonatal development which results in neuromotor paralysis and associated neuromuscular symptoms. Features of CP include motor disability due to the lack of muscle control, often accompanied by sensory disorders, mental retardation, speech disorders, hearing loss, epilepsy, behavior disorders, etc. There are increasing chances of treatment of dental patients with cerebral palsy, as the occurrence of CP is increasing with the decrease in infant mortality and an increase in immature birth and premature birth and also, there is a trend to pursue of higher quality of life. Reports on the relationship between CP and maxillofacial deformity are uncommon, but it is well known that the unbalance and discontrol of the facial muscles, lip, tongue and the jaws leads to malocclusion and temporomandibular joint disorders, and statistics show that class 2 relationship of the jaws and open bite is frequently reported. However, it is difficult to perform maxillofacial deformity treatment, which consists of orthodontic treatment, maxillofacial surgery and muscle adaptation training, due to difficulties in communication and problems of muscle adaptation caused by difficulties in motor control which leads to a high recurrence rate. This case report is to trearment of maxillofacial deformity in CP patient. A 26 year old female patient came to the department with the chief complaint of prognathism of the mandible and facial asymmetry. According to the past medical history, she was diagnosed as cerebral palsy 1 week after birth, classified as GMFC, classII accompanied with left side torticollis. The patient's intelligence was moderate, and there were no serious problems in communication. For two years time, the patient underwent lingual frenectomy, pre-operation orthodontic treatment and then bimaxillary orthognathic surgery to treat mandibular prognathism and facial asymmetry followed by rehabilitatory exercise of facial muscle. After 6 months of follow up, there was a good result. This is to report to the typical signs and symptoms of DFD in CP patient and the limitation of the usual method of the treatment of DFD in CP patient with literature review.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.12
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• pp.141-146
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• 2016

HEVC/H.265 is the latest joint video coding standard proposed by ITU-T SG 16 WP and ISO/IEC JTC 1/SC29/WG 11. In H.265, pictures are divided into a sequence of coding tree units(CTUs), and the CTU further is partitioned into multiple CUs to adapt to various local characteristics. Its coding efficiency is approximately two times high compared to previous standard H.264/AVC. However according to the size of extended CU(coding unit) and transform block, the hardware size of PMR(prediction/mode decision/reconstruction) block within video encoder is about 4 times larger than previous standard. In this study, we propose a new less complex hardware architecture of PMR block which has the most high complexity within encoder without any noticeable PSNR loss. Using this simplified block, we can shrink the overall size the H.265 encoder. For FHD image, it operates at clocking frequency of 300 MHz and frame rate of 60 fps. And also for the test image, the Bjøntegaard Delta (BD) bit rate increase about average 30 % in PMR prediction block, and the total estimated gate count of PMR block is around 1.8 M.

• Journal of The Korean Association For Science Education
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• v.31 no.2
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• pp.239-255
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• 2011

As a case study on the use of coteaching in science instruction for science-gifted elementary students, this paper analyzed the characteristics of coteaching science instruction for science-gifted elementary students by plan, performance, and reflection-evaluation stages of the classes. To do this, we observed two teachers' coteaching science instruction for science-gifted elementary students during twelve classes and analyzed the taped videos, their journals, and the transcripts for in-depth interviews with them. The results indicated that the characteristics of the coteaching science instruction, in the planning stage of the classes, showed improvement in the quality of the sciencegifted education programs, the reduction of the psychological burdens of developing the programs, and some efficiency loss due to the joint preparation of the classes. The characteristics in the performance stage of the classes include the seamless progression of the classes through the division of roles, the increase of the students' opportunity to explore, the supplement of the teachers' inadequate descriptions and the overlooked contents, the increase of the interaction between teachers and students and/or the interaction among students, the reduction of the risk of accidents in experiments, and the reduction of the responsibility for teaching. Finally, the characteristics in the reflectionevaluation stage of the classes could be attributed to the diversity of the evaluation viewpoints, the increase of the learning opportunities to develop the teaching professionalism, and the increase of the fear for assessing my own classes.

• Journal of Yeungnam Medical Science
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• v.10 no.2
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• pp.388-399
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• 1993

The adequate treatment of tibia fracture is one of the most difficult due to severe commiuntion, open wound, delayed union, angulation deformity and infection. We treated 38 fractures of the tibia by Interlocking intramedullary nail from Feb. 1983 to Mar. 1993, 35 cases of the tibia fracture were fresh, 13 cases of fracture were open. The other 3 cases were delayed union and nonunion. The Mean follow-up was 14.0 months. The results were as followings. 1. Of the 38 fractures, 37 fractures united and the mean union time was 18.7 weeks. 2. Interlocking intramedullary nail could be used to the majority of fractures of the proximal & distal tibia shaft fractures. 3. The Interlocking nail had rigid rotational stability and was appropriate for the treatment in severe unstable fractures, commninution and open with bone loss. 4. Delayed union or nonunion was a good indication for intramedullary nailling. 5. The major complication were valgus deformity of 2 cases, varus deformity of 1 case, 1 case deep infection. 6. Interlocking intramedullary nailing provided rigid fixation of fracture and then made early joint motion exercise and ambulation.

• Journal of Broadcast Engineering
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• v.18 no.2
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• pp.271-282
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• 2013

Recently, ITU-T/VCEG and ISO/IEC MPEG have started a new joint standardization activity on video coding, called High Efficiency Video Coding (HEVC). This new standard gives significant improvement in terms of picture quality for high resolution video. The main challenge in this upcoming standard is the time complexity. In this paper we have focused on CU splitting algorithm. We have proposed a novel algorithm which can terminate the CU splitting process early based on the RD cost of the parent and current level and the motion vector value of the current CU. Experimental result shows that our proposed algorithm gives on average more than about 10% decrement in time over ECU [8] with on average 1.78% of BD loss on the original.