• 대한조선학회논문집
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• 제54권6호
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• pp.485-491
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• 2017

An experimental study on the reduction of vertical motion of floating body using floating-submerged body interaction was performed in a two-dimensional wave channel. The system consisting of a floating and submerged body that only move vertically was modeled. This experiment was designed based on the results of theoretical analysis of two-body interaction. The results showed a tendency to significant reduction of heave RAO of floating body due to submerged body. Various connection line stiffness and dimension of the submerged body were applied to investigate the effect of two-body interaction on the vertical motion of the bodies, Heave RAOs of the floating-submerged body were compared with those of single body. From the comparison study, we obtained an optimum condition of connection line and dimension of submerged body for maximum heave reduction at the resonant period of single body.

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2001년도 추계학술대회
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• pp.48-48
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• 2001

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.309-314
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• 1999

We report dimension-reduced and photon-induced quantum rings naturally formed in a vertical-cavity-like active microdisk plane due to Rayleigh＇s band of whispering gallery modes. The √T- dependent redshift, microampere-range threshold currents, λ/2 lightwave ordering, and chaotic properties are also discussed.

• 대한치과보철학회지
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• 제25권1호
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• pp.155-160
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• 1987

• 대한기계학회논문집A
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• 제23권7호
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• pp.1065-1074
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• 1999

This study proposes the analysis and evaluation method of time series ultrasonic signal using the chaotic feature extraction for ultrasonic pattern recognition. Features extracted from time series data using the chaotic time series signal analysis quantitatively welding defects. For this purpose analysis objective in this study is fractal dimension and Lyapunov exponent. Trajectory changes in the strange attractor indicated that even same type of defects carried substantial difference in chaoticity resulting from distance shills such as 0.5 and 1.0 skip distance. Such differences in chaoticity enables the evaluation of unique features of defects in the weld zone. In experiment fractal(correlation) dimension and Lyapunov exponent extracted from 6dB ultrasonic defect signals of weld zone showed chaoticity. In quantitative chaotic feature extraction, feature values(mean values) of 4.2690 and 0.0907 in the case of porosity and 4.2432 and 0.0888 in the case of incomplete penetration were proposed on the basis of fractal dimension and Lyapunov exponent. Proposed chaotic feature extraction in this study enhances ultrasonic pattern recognition results from defect signals of weld zone such as vertical hole.

• 한국의류학회지
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• 제40권4호
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• pp.591-599
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• 2016

This study analyzes the somatotype of tall stature Korean women's lower body for proper slack patterns. The study subjects consist of 350 statures over 165cm in 18-59 aged women's of Size Korea 2010. Descriptive statistics, factor analysis, cluster analysis, ANOVA, Duncan test were used for analysis using SPSS 19.0. The result are as follows: Factor 1 was the horizontal dimension of waist and hip, factor 2 was the vertical dimension of lower body, factor 3 was the horizontal dimension of the lower limbs, factor 4 was the crotch length, and factor 5 was the horizontal dimension of hip. The lower body was divided into 3 types based on analysis of the above factors. Type 1 (46.6%) represented stout type with a thick and medium length of crotch and leg. Type 2 (22.7%) represented a curve type from waist to hip with long crotch length, while short and thin leg. Type 3 (30.7%) was referred as slender type, with short crotch length, while long and thin leg.

• 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.

• 대한치과보철학회지
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• 제51권4호
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• pp.339-346
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• 2013

외상이나 선천적 결손에 의한 영구치아의 결손은 치료 방법과 적용 시기의 결정이 치료의 예후에 중요한 영향을 미친다. 본 증례는 성장기 환자로서 치아와 두개안면골 상태에 대한 정확한 진단 및 적절한 치료방법을 선택하고 성장 양식을 고려해서 일정기간 임시수복물과 임시 가철성 보철물을 사용하였으며, 성장 완료 후 임플란트 등을 이용한 고정성 보철수복 치료를 시행한 경우로써 교정과와 보철과의 협진 진료, 붕괴된 교합고경의 재확립 과정, 임플란트 보철치료 시 고려해야할 사항들에 대해 발표하고자 한다.

• 대한치과보철학회지
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• 제33권2호
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• pp.231-239
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• 1995

When the complete denture is made, the record base for jaw relation is divided into temporary record base and permanent record base. However, The temporary record base include some disadvantages such as, the lackness of intimate contact between model and base, the lackness of retention during the jaw relation registration, When we obtained jaw relation the permanent record bases made from heat curing resin were utilized. We could get several advantages as follows : 1. The permanent record base provided intimate contact between the model and record base. 2. In fabricating occlusal rim on record base, the dimensional change of record base was little because the permanent record base was lesser influenced to thermal change of occlusal rim than the temporary record base. 3. At the stage of jaw relation, the retention of final denture could be early checked. 4. It could be able to get more accurate registration of jaw relation because all procedure were done on the same base during the jaw relation, artificial teeth arrangement, try-in, and final denture construction. 5. Although there was an inconvenience due to double curing procedure, the shrinkage rate in resin polimerization was relatively reduced so that more dimensional stability could be taken.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권5호
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• pp.430-435
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• 2006

Purpose : The aim of this study was to investigate healed bovine bone particles ($Bio-Oss^{(R)}$) and absorbable collagen sponge ($CollaPlug^{(R)}$) applied extraction socket site at 4-6 months' post-extraction. Material and methods : From August, 2004 to October, 2005, 17 sockets in 5 adult patients were selected out of the patients whose received ridge preservation using bovine bone particles and absorbable collagen sponges at Dept. of oral and maxillofacial surgery in Samsung Medical Center. There were 5 male patients, ages 30 to 58 years. Immediate postoperation and 4-6 months after operation study models were compared to evaluate the ridge dimension by measuring vertical height and horizontal width of alveolar ridge. Results : The measurements at 4-6 months revealed, in the ridge dimension, a loss of vertical height of 0.91${\pm}$0.40mm and horizontal width of 1.25${\pm}$0.58mm. There was no adverse reaction. Conclusion : This study suggests that treatment of extraction sockets with graft materials and collagen sponges is valuable in preserving alveolar bone in extraction sockets and preventing alveolar ridges defects.