• 대한의용생체공학회:의공학회지
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• 제27권4호
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• pp.180-188
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• 2006

Bristles for the prosthetic and periodontally involved patients are investigated based on previous studies. Specifically, the ideal location and dimensions of bristles for the patients who were installed with fixed prostheses and severely involved periodontitis were investigated. 3D (Three-Dimensional) scanner was used to develop 3D visual models of bristles and teeth. These models were used for designing the ideal bristles. In the design, the interproximal area of dental arch and bristle must be maximized and the standard teeth may have to be chosen from many gypsum molds. During the design process the factors that influence plaque removal by the bristle were considered.

• 대한치과교정학회지
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• 제48권4호
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• pp.262-267
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• 2018

The aim of this study was to test the clinical application of an intraoral scanner for serial evaluation of orthodontic tooth movement. The maxillary dentitions of eight patients with fixed orthodontic appliances were scanned using an intraoral scanner at the beginning of treatment (T0), and at 1 month (T1), 2 months (T2), 3 months (T3), and 4 months (T4) after T0. The serial digital models were superimposed on the palatal surface as a reference area, and the linear and angular changes of the central incisors, canines, and first molars were evaluated. The intraclass correlation coefficient and method errors showed that this method was clinically acceptable. Various types of orthodontic tooth movements, including minute movements, could be observed every month. The intraoral scanner and digital superimposition technique enabled the serial evaluation of orthodontic tooth movement without taking serial impressions and/or acquiring radiographs.

• Journal of Korean Dental Science
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• 제17권1호
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• pp.1-13
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• 2024

With the advances of digital scanning technology in dentistry, the interests in facial scanning in orthodontics have increased. There are many different manufacturers of facial scanners marketing to the dental practice. How do you know which one will work best for you? What questions should you be asking? We suggest a clinical guideline which may help you make an informed decision when choosing facial scanners. The characteristics of 7 facial scanners were discussed in this article. Here are some considerations for choosing a facial scanner. *Accuracy: For facial scanners to be of real value, having an appropriate camera resolution is necessary to achieve more accurate facial image representation. For orthodontic application, the scanner must create an accurate representation of an entire face. *Ease of Use: Scanner-related issues that impact their ease of use include type of light; scan type; scan time; file type generated by the scanner; unit size and foot print; and acceptance of scans by third-party providers. *Cost: Most of the expenses associated with facial scanning involve the fixed cost of purchase and maintenance. Other expenses include technical support, warranty costs, transmission fees, and supply costs. This article suggests a clinical guideline to make the right choice for facial scanner in orthodontics.

• 한국지리정보학회지
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• 제12권1호
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• pp.54-63
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• 2009

해안 침식에 따른 해안선 변화를 모니터링하기 위해 해빈의 표면 자료를 획득하기 위한 다양한 방법들이 적용되어 오고 있다. 본 연구는 지상용 레이저 스캐너와 RTK-GPS를 활용하여 해빈 지형을 구현하여 구축할 수 있는 가능성을 제시하고자 한다. 지상 레이저 스캐닝을 실시하여 20cm 측점 간격으로 취득된 3차원 자료와 수치 사진으로부터 화상이 피복된 수치표면모형을 생성하였다. 또한 7개월 후에 동일 지역을 1초 수신 간격의 RTK-GPS를 이용하여 직접 측정하여 1.9cm의 측량 정확도로 해빈 모형을 구현하였다. 계절적으로 많은 변화가 예상되는 해빈 지역에 즉각 대응적이면서 양호한 결과를 요하는 측정일 경우는 지상용 레이저 스캐너의 활용이 가능하며, RTK-GPS는 해빈 모형의 측점수와 관계가 있어 측점을 직접 관측해야 하는 애로사항이 있지만 지상용 레이저 스캐너에서 발생하는 사각지대를 보정하면서 3차원 모형을 구현할 수 있다. 따라서 동해안 해빈의 지역적 특성을 고려할 때 RTK-GPS와 지상용 레이저스캐너의 조합 활용하여 해빈 모형 자료를 구축하는 것이 보다 정밀한 방법일 것이다.

• 산업기술연구
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• 제35권
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• pp.47-53
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• 2015

Recent extreme weather events and natural disasters are causing rapid aging of the ancient structures with cultural value. It has threatened the safety and management. The construction design documents are not kept for such long time. Even if they are, they seem to be mismatched with the design structures due to corrosive effects. For these reasons, Korea has been facing difficulties in maintenance, reengineering and safety evaluation. In this study, three dimensional point cloud surface of bobsleigh is obtained using 3D LiDAR scanner. The obtained structure is compared with the original design and found to be highly accurate. The study shows the application of reverse engineering technique and its potential use for other civil structures.

• 대한치과교정학회지
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• 제44권6호
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• pp.281-293
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• 2014

Objective: Esthetic improvements during orthodontic treatment are achieved by changes in positions of the lips and surrounding soft tissues. Facial soft-tissue movement has already been two-dimensionally evaluated by cephalometry. In this study, we aimed to three-dimensionally assess positional changes of the adult upper lip according to simulated maxillary anterior tooth movements by white light scanning. Methods: We measured changes in three-dimensional coordinates of labial landmarks in relation to maxillary incisor movements of normal adults simulated with films of varying thickness by using a white light scanner. Results: With increasing protraction, the upper lip moved forward and significantly upward. Labial movement was limited by the surrounding soft tissues. The extent of movement above the vermilion border was slightly less than half that of the teeth, showing strong correlation. Most changes were concentrated in the depression above the upper vermilion border. Labial movement toward the nose was reduced significantly. Conclusions: After adequately controlling several variables and using white light scanning with high reproducibility and accuracy, the coefficient of determination showed moderate values (0.40-0.77) and significant changes could be determined. This method would be useful to predict soft-tissue positional changes according to tooth movements.

• 한국인터넷방송통신학회논문지
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• 제13권3호
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• pp.135-140
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• 2013

본 연구에서는 매립장의 체적관리를 위한 체적 모니터링 시스템 구현에 대한 연구에 대해 논의한다. 레이저 로봇 기술에 기반한 삼차원 스캐너를 제작하여 삼차원 물체의 표면에 대한 포인트 클라우드(point cloud)를 이용한 매립장의 쓰레기 체적 감시 시스템을 제안하였다. 이를 통해 연속적으로 매립장의 쓰레기 체적 변화를 감시할 수 있게 되었으며 매립장 수명의 가용한 쓰레기 매립 수명을 예측할 수 있게 되었다. 그리고 완성된 매립장 체적 감시 시스템은 안성시 매립장에 구현되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1299-1302
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• 2004

A real object duplication system (RODS), including three dimensional (3D) scanner and solid freeform fabrication system (SFFS), is a device to make three-dimensional objects directly from the drawing or photo data. A Selective Multi-Laser Sintering (SMLS) process designed in this paper is by which computer images received using 3D scanner are built up from polymer powder on building room of large size using dual laser at industrial type SFF system. Using the process can rapidly produce real object duplication components of industrial type such as cylinder, engine block, chassis of automobile, etc. In this paper, the industrial type SFF system using SMLS process is manufactured and the system is satisfied with high precision and high speed processing technique. To research characteristics of each part for theindustrial type SFF system, a structure and thermal analysis and test of each part is carried out. Also, to achievement of high performance for industrial type SFF system, design and fabrication for the structure, heater, nitrogen supply, laser and control part are carried out.

• 치위생과학회지
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• 제14권2호
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• pp.94-100
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• 2014

본 연구는 임상에서 널리 사용되고 있는 3종류의 탄성 인상재를 치과용 백색광 스캐너로 스캔하여 얻어진 데이터와 석고 지대치 모형과의 차이를 비교분석하였다. 인상재의 물성 차이가 3차원 디지털 모형의 정확성에 어떠한 영향을 미치는지 3차원 중첩 분석법을 통해 평가함으로써 다음과 같은 결과를 얻었다. 석고 지대치 모형과 3종류의 인상재를 토대로 채득된 디지털 모형의 차이를 비교한 결과, HB 그룹이 $9.80{\pm}1.52{\mu}m$ 로 가장 큰 차이를 보였으며, XLB 그룹이 $5.10{\pm}1.45{\mu}m$로 가장 작은 차이를 나타내었다. 음형의 인상체 간의 정확성에 있어서는 측정된 평균값이 통계적으로 유의한 차이를 보였다(p<0.05). Color difference map의 결과에서도 HB 그룹에 비해 XLB 그룹이 오차가 0에 가까운 연두색의 분포가 넓게 나타났기에, 더욱 안정적이며 정확한 디지털 모형 채득이 가능한 탄성 인상재라는 결론을 내릴 수 있다. 아직까지는 음형의 인상체 스캔방식은 표면의 혈흔이나 난반사, 중합 수축 등 좀 더 개선하고 보완해야 할 문제점들이 존재하기 때문에 널리 사용하진 않지만, 석고 모형과 비교하였을 때 전체적인 오차범위가 크지 않기에 임상적으로 허용될만한 수준으로 생각된다.

• 열처리공학회지
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• 제35권2호
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• pp.66-73
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• 2022

Partial-hardened hot stamping has been well known to be very effective to absorb more energy in automotive lateral crash. Hardness distribution and dimensional change after partial-hardened hot stamping have been studied to find out effect of thermal deformation of the heated hot stamping die on dimensional accuracy of automotive center pillar. Soft zone of commercial center pillar showed 275~345 in Vickers hardness, indicating bigger non-uniformity which resulted from thermal deformation of heated die. Dimensional changes in soft zone of the commercial center pillar measured by three dimensional scanner were much bigger than that in hard zone. It has been found that hot stamping die compensation considering thermal deformation in soft zone causes a significant decrease in hardness deviation in the soft zone, corresponding to 20 percent of commercial center pillar and subsequently leads to much higher dimensional accuracy.