• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권8호
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• pp.2797-2820
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• 2015

In order to accommodate huge number of antennas in a limited antenna size, a large scale antenna array is expected to have a three dimensional (3D) array structure. By using the Active Antenna Systems (AAS), the weights of the antenna elements arranged vertically could be configured adaptively. Then, a degree of freedom (DOF) in the vertical plane is provided for system design. So the three-dimension MIMO (3D MIMO) could be realized to solve the actual implementation problem of the massive MIMO. However, in 3D massive MIMO systems, the pilot contamination problem studied in 2D massive MIMO systems and the inter-cell interference as well as inter-vertical sector interference in 3D MIMO systems with vertical sectorization exist simultaneously, when the number of antenna is not large enough. This paper investigates the interference management towards the above challenges in 3D massive MIMO systems. Here, vertical sectorization based on vertical beamforming is included in the concerned systems. Firstly, a cooperative joint vertical beams adjustment and pilot assignment scheme is developed to improve the channel estimation precision of the uplink with pilots being reused across the vertical sectors. Secondly, a downlink interference coordination scheme by jointly controlling weight vectors and power of vertical beams is proposed, where the estimated channel state information is used in the optimization modelling, and the performance loss induced by pilot contamination could be compensated in some degree. Simulation results show that the proposed joint optimization algorithm with controllable vertical beams' weight vectors outperforms the method combining downtilts adjustment and power allocation.

• 한국운동역학회지
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• 제16권4호
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• pp.21-30
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• 2006

The purpose of the study is to search for the possibility of the application of kinematics analysis to physical education at schools and expand its scope of application. This study chose 9 college students majoring in physical education and classified them into type A group who can make the straight, vertical handstand, type B group whose waist is bent, type C group who cannot handstand completely. The center of mass, distance between hand and leg, and the angle and angular velocity of each joint were obtained. The result of this study is this. 1. The time for CM showed 6:4 for A group and 5:5 for B and C groups. The distance between hand and foot in the event 3 was 44% of the height for A group, and 41% for B and C groups. A Group showed the higher CM positional significant difference, it was vertically direction below the hip joint at front. For significant difference of the B Group showed horizontal and vertical velocity of the CM, the highest vertical was obtained in phase 3. The difference of angle of shoulder join in the flexion/extension was showed gradually extension event 2 and the height angular velocity was at phase 3 in the A group. 2 The analysis of the handstand motion revealed that the phase 3, but the maintenance of posture start part the handstand is also very important. Through these results, this study confirmed that the time for phase of the CM, horizontal and vertical positions, velocity, the distance between hands and foot, and the difference of the angle and angular velocity of hip joint and shoulder joint can be set as the variables of analysis. It was also definite cause that the handstand motions of college students majoring in physical education had many difference in performance.

• 대한심미치과학회지
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• 제32권1호
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• pp.23-32
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• 2023

비기능적 습관을 가진 환자는 턱관절 장애, 저작 근육의 근막통증증후군 등과 함께 치아의 광범위한 마모를 유발한다. 지속되는 교모는 수직교합고경의 감소를 동반하게 되며 이는 안모의 변화, 저작 효율 저하, 측두하악 관절 장애 등의 문제가 발생할 수 있다. 이런 수직교합고경 감소 환자의 3차원적인 교합 회복과 재구성을 위해서는 정확한 진단 및 분석과 예지성 있는 치료계획 수립이 필요하며, 생리적인 수직교합고경의 회복 및 정상적인 교합평면 재설정을 동반한 보철치료가 필요하다. 본 증례는 구강 악습관에 의한 전반적인 치아의 마모와 저작근의 불편감, 그리고 수직교합고경 감소로 인한 심미적 불만족을 호소하는 환자의 수직교합고경 증가를 동반한 완전 구강 회복 증례이다. 교합안정장치를 통한 측두하악관절의 안정과 고딕아치 기록장치를 이용한 악간관계 재설정 및 임시 수복물을 통한 경과 관찰을 통해 기능적, 심미적으로 좋은 결과를 보였기에 이를 보고하고자 한다.

• Journal of Oral Medicine and Pain
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• 제17권2호
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• pp.63-73
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• 1992

This study was performed for the purpose of investigating the relation between width of temporomandibular joint space and craniofacial morphology in patients with CMDs. The subjects utilized here were aged from 16 to 63 years old and 19 male and 46 female. For the study, each patient was taken radiographs by Transcranial and Lateral Cephalographic projection and the films were traced with routine method. The measured items were anterior, superior, posterior joint space and relative condylar position to the deepest part of glenoid fossa in Transcranial film and items related vertical and/or horizontal growth in Cephalogram. The data were processed with SPSS/PC+ package for statistical analysis. The obtained results were as follows : 1. Anterior joint space in affected side were wider than that of unaffected side, but for superior and posterior joint space, the value of unaffected side were more than those of affected side. 2. Superior or posterior joint space of affected side were significantly correlated with items related vertical growth, such as ramus height, Jarabak ratio, FMA. From this, the following cold be proposed, the wider the joint space of superior or posterior aspect of affected side was, the more the patient showed growth pattern of counter clockwise. 3. Superior or posterior joint space of affected side were significantly correlated with items related horizontal growth, such as SNPo, NAPo, APDI and ANB. From this the following could be proposed, the wider the joint space of superior or posterior aspect of affected side was, the more the patient showed anterior displacement of mandible. 4. It would be proposed that the diagnositic value of superior and posterior joint space of affected side in transcranial radiograph was excellent.

• 대한건축학회논문집:구조계
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• 제35권9호
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• pp.151-158
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• 2019

A concrete core is used widely as lateral stability systems in high-rise modular buildings. As an alternative to traditional cast in-situ core, the precast concrete(PC) method can accelerate the construction of reinforced concrete cores. A core composed of precast elements differs from a in-situ core in having connections between the precast elements. The typical vertical connection between PC panels is consisted of shear keys, loop bars, lacer bars and grout. In this study, the effect of vertical connection components on shear strength is investigated experimentally. The test results show that the contribution to the shear strength is greater in order of grout strength, shear keys, lacer bars and loop bars. In addition, the numerical models to estimate the shear strength according to two crack patterns in the vertical joint of the PC panels are derived. The feasibility of the numerical models is evaluated by comparing the estimated shear strength and the test results.

• 한국운동역학회지
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• 제34권1호
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• pp.18-24
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• 2024

Objective: The purpose of this study was to evaluate the effects of an 8-week velocity-based training on the maximum vertical jump in elite sprinters. Method: Ten elite sprinters were participated in this study (age: 21 ± 0.97 yrs., height: 179 ± 3.54 cm, body mass: 72 ± 2.98 kg). An 8-week velocity-based power training was provided to all subjects for twice per week. Their maximum vertical jumps were measured before and after velocity-based training. A 3-dimensional motion analysis with 8 infrared cameras and 4 channels of EMG was performed in this study. A paired t-test was used for statistical verification. The significant level was set at α=.05. Results: There were no statistically significant differences were found between pre and post the training (p>.05). However, most variables included jump record, knee joint ROM, and muscle activation of rectus femoris showed increased pattern after the training. Conclusion: In this study, an 8-week velocity-based training did not showed the significant training effects. However, knee joint movement which is the key role of the vertical jump revealed positive kinematic and kinetic pattern after the training. From this founding, it is believed that velocity-based training seems positively affect the vertical jump which is the clear measurement of mechanical power of sprinter. In addition, to get more clear evidence of the training more training period would be needed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.393-394
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• 2023

This paper provides an overview of seismic design considerations for vertical construction joints of a slurry walls used as a permanent basement walls.

• 한국지반공학회논문집
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• 제34권3호
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• pp.43-56
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• 2018

해상처분장의 호안구조물 및 연직차수공으로 강관시트파일이 주로 사용되며, 강관시트파일은 이음부를 연결하여 주열식으로 설치가 되는 만큼 해상 고유의 횡방향 외력에 대한 구조적인 안정성이 확보되어야 한다. 본 연구의 목적은 새로 개발된 연직차수공 이음부의 구조적인 성능을 평가하는 것이다. 먼저 기존 연직차수공 이음부의 문제점을 고찰하고 시공 및 유지보수 측면에서 기존 이음부 형식과의 차별성을 갖도록 새로운 형태의 DHLT(Double H with L-T) 연직차수공 이음부를 개발하였다. 개발된 DHLT 이음부의 실규모 모형을 제작하고 이음부에 그라우트를 채워 양생시킨 후 압축 및 인장강도실험을 수행하고 그 결과를 기존 연구결과와 비교하였다. 실험결과, DHLT 이음부의 압축강도와 인장강도는 그라우트와 강재의 영향으로 인해 기존 이음부 연구결과에 비해 다소 과소평가되었다. 특히 압축강도 실험의 경우 DHLT 이음부의 비대칭 형상으로 인해 그라우트에 균열이 발생하기 전에 강재에서 먼저 항복이 발생하는 결과를 나타내었다. 본 연구를 통해 연직차수공 개발시 이음부 강도발현에 영향을 끼칠 수 있는 요인을 파악할 수 있었으며, 이를 근거로 더 향상된 연직차수공을 개발할 수 있을 것으로 기대된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권2호
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• pp.102-108
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• 2015

In surgery for facial asymmetry, mandibles can be classified into two types, rotational and translational, according to the required mandibular movements for surgery. During surgery for rotational mandibular asymmetry, a bilateral sagittal split ramus osteotomy (BSSRO) may cause a large bone gap between the proximal and distal segments as well as condylar displacement, resulting in a relapse of the temporomandibular joint disorder, especially in severe cases. The intraoral vertical ramus osteotomy has an advantage, in this respect, because it causes less rotational displacement of the proximal segment on the deviated side and even displaced or rotated condylar segments may return to their original physiologic position. Unilateral intraoral vertical ramus osteotomy (UIVRO) on the short side combined with contralateral SSRO was devised as an alternative technique to resolve the spatial problems caused by conventional SSRO in cases of severe rotational asymmetry. A series of three cases were treated with the previously suggested protocol and the follow-up period was analyzed. In serial cases, UIVRO combined with contralateral SSRO may avoid mediolateral flaring of the bone segments and condylar dislocation, and result in improved condition of the temporomandibular joint. UIVRO combined with contralateral SSRO is expected to be a useful technique for the treatment of rotational mandibular asymmetry.

• 한국운동역학회지
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• 제15권3호
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• pp.175-183
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• 2005

This study investigates the kinetic characteristics of the Driggs motion in horse vaulting by stages through the three-dimensional video analysis of YTY and TABARA who won a high score and a low score respectively from the Driggs motion in horse vaulting during the Daegu Universiade 2003, which involves putting one's hands on the horse vaulting rotating sideways, stretching and rotating backward in the air, and twisting 900 degrees, so as to help develop the techniques of Korean gymnastic athletes. From the analyses of the duration of body center, horizontality, vertical position and horizontality, vertical speed and angle factors for each of four phases from the contact of the board to the takeoff from the horse vaulting. I arrived at the following conclusions: 1. It was found that the motion of bending oneself forward while rapidly stretching the knee joint when taking off from the board increases the horizontal speed of body center and shortens the time of the first jump. 2. It was found that S1 who won a high score shortened the time of the contact and takeoff from the horse vaulting and enlarged the shoulder joint angle for full blocking motion. It was also found that horizontal speed decreased while vertical speed increased when you rapidly stretch the right elbow joint while taking off from the horse vaulting. 3. It was found that horizontal distance was shortened to increase the height and time of staying in the air during the second jump.