• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.377-390
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• 2021

Reverse total shoulder arthroplasty (RTSA) is a surgical method that has recently been conducted in widely irrepairable rotator cuff tears with pseudoparalysis, cuff tear arthropathy, and osteoarthritis of the shoulder joint. Several topics can be described, but this review article provides an opinion on the criteria for the choice of implant in RTSA.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.4
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• pp.32-42
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• 2010

In this paper, we represent considering parameters for design of a Cartesian vector modulator predistorter to maximize linearity improvement of the predistorter and propose an advanced Cartesian vector modulator predistrotrer with nonlinear starting point control circuit. In order to confirm the performance of the proposed predistorter, the predistorter is applied to power amplifier with 15 W output power for 2.5 GHz band mobile WiMax 1-FA signal. From the measured results, ACLR of -45.3 dBc with 4 dB improvement of ALCR compared with the previous predistorter is obtained and linearity improvement range is also extended.

• The korean journal of orthodontics
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• v.28 no.6 s.71
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• pp.981-989
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• 1998

Positions, angulation and mesiodistal dimension of lower incisors are important in esthetics, occlusion and post-treatment stability of tower arch. When lower incisor is congenitally missing, problems such as increased overjet and overbite, closing in of adjacent teeth and size/space discrepancies may occur. When creating treatment plans, incisor position and angulation, lip support, anteroposterior skeletal relationship canine-molar relationship, overjet overbite, remaining growth potential, crowding and anterior tooth ratio have to be considered. For an accurate analysis of incisal size discrepancy, diagnostic model set-up may be helpful. The two patients in this presentation both had two lower incisor missing, but the degree of crowding, skeletal relationship, lip support, molar relationship are different and therefore treatment plan was different as well. Long term follow-up may be necessary for stability and retention.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.323-328
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• 2001

Anterior open bite is one in which the teeth in the anterior portion of the maxilla and mandible are vertically apart and lack the overlapping necessary for the incisive function when the mandible is in closed position. Anterior open bite is a result of the interaction of many different etiologic factors including thumb and finger sucking, lip and tongue habits, airway obstruction, skeletal growth abnormalities and its tendency may appear with any type of skeletal patterns, such as Class I, II or III malocclusion types. Though the treatment methods for anterior open bite are various, the conventional FR-4, designed by Rolf Fr$\"{a}$nkel, is known to be effective in treating open bite cases with Class I or II skeletal patterns. It is due to that an incidence of skeletal Class II is high in the Occidentals, and open bite is accompanied by these malocclusion type in many cases. However, an incidence of skeletal Class III is high in the Orientals, and open bite is sometimes accompanied by skeletal Class III in many cases. Although the use of the conventional FR-4 was effective in the treatment of open bite, skeletal Class III would be worsened. So, a modified FR-4(placing the labial bow in the lower, the labial pads in the upper) was designed for the treatment of patients showing skeletal Class III and open bite.

• 한국정보통신설비학회:학술대회논문집
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• 2006.08a
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• pp.62-66
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• 2006

본 논문은 도허티 증폭기 및 포락선 전치 왜곡기를 이용한 전력 증폭기의 효율 및 선형성 개선에 관한 것이다. 전력 증폭기의 효율을 개선하기 위하여 도허티 증폭기를 제작하여 효율 특성을 개선하였으며, 포락선 전치 왜곡기를 이용하여 도허티 증폭기의 선형성 개선량에 대하여 조사하였다. 제작된 도허티 증폭기는 AB 급으로 동작시킨 전력 증폭기와 비교하여 출력 전력 10W에서 8.5%의 효율 개선 효과를 보였으며, 출력 전력 40W에서 12.6%의 효율 개선 특성을 나타내었다. 포락선 전치 왜곡기를 이용한도 허티 증폭기는 출력 전력 10W에서 7dB의 선 형성 개선 효과를 나타내었다. IMT-2000 주파수 대역에서 WCDMA down-link 4 carrier 신호를 이용하여 출력 전력 10W에서 측정한 결과 AB 급으로 동작하는 전력 증폭기와 비교하여 4.2%의 효율 개선 및 6.3dB의 선형성 개선 효과를 나타내었다.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.367-376
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• 2021

An increasing number of reverse total shoulder arthroplasty procedures has been performed since its introduction to South Korea in 2007. This review discusses the biomechanical rationale behind the development of reverse total shoulder arthroplasty and its outcomes over time. In addition, this paper mentions ways to minimize the risk of complications that may occur and how to manage those complications.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.125-133
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• 2011

Purpose: The purpose of the present article is to help orthopedic surgeons better understand the function and performance of reverse total shoulder arthroplasty, and also to help them perform the most proper surgical technique for reconstruction. Materials and methods: In this article, the specific technical aspects and pitfalls of reverse total shoulder arthroplasty were reviewed in depth. Additionally, the current issues relevant to the reverse total shoulder arthroplasty such as scapular notching and restoration of active external rotation were discussed. Results and conclusion: An understanding of the biomechanics of reverse total shoulder arthroplasty and the technical details and pitfalls of its implantation are critical in order to provide the best functional outcome without increasing the risk of complications.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1C
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• pp.40-44
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• 2010

The timing error detector(TED) employed in the closed loop type timing synchronization scheme for an MQASK all digital receiver suffers from the selfnoise-induced timing jitter. To eliminate the timing jitter a prefilter can be added in front of the TED. The prefilter method, however, degrades the stability and timing acquisition performance due to the loop delay and increases the complexity of the synchronizer. This paper proposes a polyphase filter type resampler approach to optimize the performance and architecture of the synchronizer simultaneously. The proposed scheme uses two resamplers which performs matched filtering and matched prefiltering so that the loop delay is minimized with minimal hardware resources. Simulation results showed an excellent acquisition performance with reduced timing jitter.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.306-316
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• 2018

Monolithic zirconia has been widely used in fixed partial dentures due to high strength and fracture toughness. Nevertheless, the usage of monolithic zirconia in anterior restoration was limited because of opacity. Recently, esthetic monolithic zirconia blocks are developed by improving translucency and using various shading systems. Manufacturer introduces 3M $Lava^{TM}$ Esthetic with increased cubic phase and fluorescent ingredients is more esthetic than previous monolithic zirconia. This case report describes favorable anterior restorations using translucent monolithic zirconia.

• The korean journal of orthodontics
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• v.33 no.5 s.100
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• pp.339-350
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• 2003

The purpose of this study was to investigate the micro-implant height and anterior hook height to prevent maxillary six anterior teeth from lingual tipping and extruding during space closure. We manufactured maxillary dental arch form, bracket and wire, using the computer aided three-dimensional finite element method. Bracket was $.022'{\times}.028'$ slot size and attached to tooth surface. Wire was $.019'{\times}.025'$ stainless steel and $.032'{\times}.032'$ stainless steel hook was attached to wire between lateral incisor and canine. Length of hook was 8mm and force application points were marked at intervals of In. Four micro-implants were implanted on alveolar bone between second premolar and first molar. The heights of them were 4, 6, 8, 10mm starting from wire. We analyzed initial displacement of teeth by various force application point applying force of 150gm to each micro-implant and anterior hook. The conclusions of 4his study are as the following : 1. When the micro-implant height was 4m and the anterior hook height was 5mm and below, anterior teeth were tipped lingually. When the anterior hook height was 6mm and above, anterior teeth were tipped labially. 2. When the micro-implant height was 6mm and the anterior hook height was 6mm and below, the anterior teeth were tipped lingually. When the anterior hook height was 6m and above, the anterior teeth were tipped labially. But lingual tipping of anterior teeth decreased and labial tipping Increased when the micro-implant height was 6mm, compared with 4mm micro-implant height. 3. When the micro-implant height was 8mm and the anterior hook height was 2mm, the anterior teeth were tipped lingually. When the anterior hook height was 3mm and above, labial tipping movement of the anterior teeth increased proportionally. 4. When the micro-implant height was 10mm and the anterior hook height was 2mm and above, labial tipping of the anterior teeth increased proportionally. 5. As the anterior hook height increased, aterior teeth were tipped more labially. But extrusion occurred on canine and premolar area because of the increase of wire distortion. 6. Movement of the posterior teeth was tipped distally during maxillary six anterior teeth retraction using micro-im plant because of the friction between bracket and were Based on the results of this study, we could predict the pattern of the tooth movement according to position of micro-implant and height of anterior hook. It seems that we can find the force application point for proper tooth movement in consideration of inclination of anterior anterior teeth, periodontal condition, overjet and overbite