• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.83-86
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• 2005

This paper presents a method for point-based 3D building reconstruction using LiDAR data and digital map. The proposed method consists of three processes: extraction of building roof points, identification of roof types, and 3D building reconstruction. After extracting points inside the polygon of building, the ground surface, wall and tree points among the extracted points are removed through the filtering process. The filtered points are then fitted into the flat plane using ODR(Orthogonal Distance Regression). If the fitting error is within the predefined threshold, the surface is classified as a flat roof. Otherwise, the surface is fitted and classified into a gable or arch roof through RMSE analysis. Based on the roof types identified in automated fashion, the 3D building reconstruction is performed. Experimental results showed that the proposed method classified successfully three different types of roof and that the fusion of LiDAR data and digital map could be a feasible method of modelling 3D building reconstruction.

• 대한소아치과학회지
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• 제47권2호
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• pp.176-187
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• 2020

이 연구는 모델 스캐너로 석고 모형을 스캔한 디지털 모형(Model scanned digital model, MSD)과 구내 스캐너로 구강을 스캔한 디지털 모형(Intraoral scanned digital model, ISD)에서 계측한 치아 근원심 폭경(Tooth width, TW)과 치열궁 길이(Arch length, AL)의 신뢰도와 재현성, 치열궁 길이 편차(Arch length discrepancy, ALD) 분석의 타당도를 평가하였다. 만 12 - 18세의 남, 여 30명에게 석고 모형, MSD, ISD를 획득하고, 2번 계측한 TW, AL의 신뢰도는 Pearson 상관 분석, 4명의 재현성은 군간 상관 분석 그리고 TW, AL 및 ALD의 타당도는 대응표본 t검정으로 평가하였다. 결과적으로 모든 군에서 계측한 TW, AL는 높은 신뢰도와 재현성을 보였고 MSD군의 ALD분석은 적절한 타당도를 보였다. ISD 군의 TW는 가장 높은 타당도를 보인 반면에, AL와 ALD분석은 유의미하게 짧게 측정되어 낮은 타당도를 보였으므로 임상가는 디지털 모델을 이용하여 공간 분석 시행 시 이를 고려해야 할 것이다.

• 대한치과교정학회지
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• 제25권2호
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• pp.209-221
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• 1995

한국인에게 적합한 설측교정장치와 이상적인 설측 치열궁 아치와이어 제작의 기초자료를 얻기위하여 정상교합자 경석고 모형 30개를 재료로 하여 설측치관의 형태와, 후지타 설측 브라켓을 위치시킨 모형에서 설측치열궁 형태를 조사하여 다음과 같은 결과를 얻었다. 각 치아에 대한 치관의 근원심 경사도와 설면의 순설측 치관 경사도의 평균치를 얻었다. 각 치아에 대한 브라??? 위치에서 설면의 수평 및 수직적 형태를 얻은 결과 대구치, 소구치, 견치는 상하악이 비슷한 모양을 보였으며, 강하악의 중절치와 측절치도 비슷한 모양을 보여 각각 브라켓 기저부를 공유할 수 있을 것으로 나타났다. 브라켈 부착위치에서의 평균 설측치열궁 형태를 얻은 결과, 그 형태는 전치부는 반원형이며 견치와 소구치 사이에 강한 오프??? 밴드가 있는 버섯 형태로서 소구치간 및 제2소구치와 대구치간에도 오프??? 밴드가 필요한 것으로 나타났다. 남녀간의 평균 설측치열궁 형태는 상악은 거의 일치하였고 하악은 여자가 남자보다 다소 작은 형태를 나타내었다.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.691-701
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• 2009

Purpose: Deviations of arterial palmar arches in the hand can be explained on the embryological basis. The purpose of this study was to provide new information about palmar arches through cadaver's dissection. The values of the location and diameter in these vessels were analyzed in order to support anatomical research and clinical correlation in the hand. Methods: The present report is based on an analysis of dissections of fifty - three hands carried out in the laboratory of gross anatomy. A reference line was established on the distal wrist crease to serve as the X coordinate and a perpendicular line drawn through the midpoint between middle and ring fingers, which served as the Y coordinate. The coordinates of the x and y values were measured by a digimatic caliper, and statistically analyzed with Student's t - test. Results: Complete superficial palmar archs were seen in 96.2 % of specimens. In the most common type of males, the superficial arch was formed only by the ulnar artery. In the most common type of females, the superficial arch was formed anastomosis between the radial artery and the ulnar artery. The average length of the superficial and deep palmar arch is $110.3{\pm}33.0mm$ and $67.9{\pm}14.0mm$ respectively. Regarding the superficial palmar arch, ulnar artery starts $-16.1{\pm}5.1mm$ on X - line, and $2.5{\pm}24.5mm$ on Y - line. Radial artery appears on palmar side $7.7{\pm}3.2mm$ on X - line, and $20.9{\pm}10.9mm$ on Y - line. But radial artery starts on $6.3{\pm}3.6mm$ on X - line, and $3.4{\pm}5.1mm$ on Y - line. Digital arteries of superficial palmar arch starts on $6.1{\pm}3.7mm$, $33.9{\pm}8.8mm$ on index finger, $1.8{\pm}3.4mm$, $40.1{\pm}7.3mm$ on middle finger, $-3.2{\pm}4.9mm$, $42.6{\pm}7.0mm$ on ring finger, and $-8.9{\pm}5.1mm$, $42.5{\pm}80mm$ on little finger in respective X and Y coordinates. Radial artery of deep palmar arches measured at the palmar side perforating from the dorsum of hand. It's coordinates were $9.7{\pm}4.8mm$ on X - line, $21.7{\pm}10.2mm$ on Y - line. Ulnar artery was measured at hypothenar area, and it's coordinates were $-20.4{\pm}6.3mm$ on X - line, and $30.6{\pm}7.4mm$ on Y - line. Conclusions: Anatomically superficial palmar arch can be divided into a complete and an incomplete type. Each of them can be subdivided into 4 types. The deep palmar arch is less variable than the superficial palmar arch. We believe these values of the study will be used for the vascular surgery of the hand using the endoscope and robot in the future.

• Structural Engineering and Mechanics
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• 제45권4호
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• pp.569-594
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• 2013

The free vibration of axially functionally graded tapered arches including shear deformation and rotatory inertia are studied through solving the governing differential equation of motion. Numerical results are presented for circular, parabolic, catenary, elliptic and sinusoidal arches with hinged-hinged, hinged-clamped and clamped-clamped end restraints. In this study Differential Quadrature element of lowest order (DQEL) or Lagrangian Interpolation technique is applied to solve the problems. Three general taper types for rectangular section are considered. The lowest four natural frequencies are calculated and compared with the published results.

• 대한치과교정학회지
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• 제37권4호
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• pp.293-304
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• 2007

본 연구에서는 임상에서 쓰이는 수종의 치과교정용 세라믹 브라켓에 교정용 호선으로 토오크 적용 시 파절에 저항하는 정도를 비교하고 그 파절 양상을 관찰하였다. $022\;{\times}\;028-inch$ slot을 가진 상악 중절치 세라믹 브라켓에 $0215\;{\times}\;027-inch$ 스테인레스 강 교정용 호선에서 발생하는 설측 치근 토오크를 적용시켜 각 15개씩 7종의 브라켓을 시험하였다. 파절 시험용 장치를 제작하고 토오크 각도를 증가시키면서 만능시험기로 세라믹 브라켓이 파절되는 순간의 토오크 값을 측정하였다. 또한 세라믹 브라켓의 파절 양상을 알아보고자 토오크 값 측정 후 파절이 일어난 부위를 관찰하고 그 위치를 기록한 주사전자현미경으로 파절면을 관찰하였다. 나타난 결과를 토대로 볼 때 세라믹 브라켓의 결정구조와 제조 방법이 파절 저항성에 크게 영향을 주는 것으로 나타났다. 단결정 알루미나 (Inspire) 브라켓이 InVu를 제외한 다결정 알루미나 브라켓에 비하여 토오크에 대한 파절 저항성이 유의성 있게 크게 나타났다 (p < 0.05). Metal slot이 삽입된 브라켓은 그렇지 않은 브라켓과 토오크에 대한 저항성에서 유의한 차이를 보이지 않았다 (p >0.05). 파절 양상에 관한 관찰에서는 metal slot이 있는 다결정 알루미나 브라켓인 Clarity는 모두 절단측 slot base에서 부분적으로만 파절이 일어났고 다른 종류의 브라켓들은 다양한 부위에서 파절이 일어났다. 본 연구 결과, 실험에 사용한 모든 세라믹 브라켓에서 파절이 일어난 순간의 토오크 값과 토오크 각은 실제로 상악 중절치의 치근을 이동하는데 필요한 토오크보다 큰 것이었으므로, 실제 임상 치료 시 적절한 파절 저항을 나타낼 것으로 보였다.

• 대한치과교정학회지
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• 제18권1호
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• pp.105-112
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• 1988

To predict duration of orthodontic treatment of malocclusion, 304 male and female patients whose orthodontic treatment was finished in department of orthodontics, Infirmary of dental college, Chosun University were studied. The duration of treatment was studied according to types of malocclusion, beginning ages of treatment, Hellman's dental ages, the determination of tooth extraction, types of tooth extraction and types of orthodontic appliance. The following results were obtained. 1. The duration of treatment was 18 months in Class I malocclusion, 20 months in Class II malocclusion and 24 months in Class III malocclusion. 2. The more early treatment was done, the more duration of treatment was needed according to beginning age of treatment and Hellman's dental ages. 3. Treatment of tooth extraction case was needed for 78 days more than that of non-extraction case. 4. The duration of treatment with unilateral extraction of premolars was the shortest (598 days) and that with single arch extraction of premolars was the longest (685 days) according to types of tooth extraction. 5. The duration of treatment by removable appliance was the shortest (237 days) and the combination of removable appliance, headgear and full banded appliance was the longest (1425 days) according to types of orthodontic appliance. 6. The duration of treatment was 18 months in typical orthodontic treatment with 4 extraction of premolar and full banded appliance.

• 대한치과보철학회지
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• 제32권2호
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• pp.235-248
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• 1994

There were many studies that distribute the partial edentulous states and examine the removable partial denture designs in the planning of removable partial denture treatment. This study was performed in the point of removable partial denture prescription to evaluate partial edentulism and its removable partial denture designs. The data was collected from the dental laboratory of each three dental colleges in Seoul and from two dental laboratories only for removable partial dentures as a prescription form. A total of 1411 cases with prescription form collected from dental laboratories were distributed for this study, then 788 cases were selected for this study. The case selection was done according to the contents of prescription form. The selected cases were divided into maxillary arch and mandibular and classified in terms of types of major connector and direct retainer, unbroken anterior teeth, Kennedy classification, the number of remaining teeth, and distribution of age and sex. The analyzed results were as follows : 1. The Kennedy classification I showed highest frequency both in maxilla and mandible. 2. The arch distribution of removable partial denture was 50.08% for maxilla and 49.92% for mandible. 3. The highest frequency in the distribution of direct retainer was the RPA clasp design. 4. The frequency of unbroken anterior 6 was 73.36% for maxilla and 82.30% for mandible. 5. The design of broad palatal strap and lingual bar revealed the highest prevalence in the major connector construction. 6. The mean number of remaining teeth per arch was 8.25 for maxilla and 8.37 for mandible. 7. The mean age of the patients supplied with removable partial denture was 52.25 years for men, 51.68 years for women, 52.11 years for maxilla, and 51.76 years for mandible and women showed more prevalence.

• 한국구조물진단유지관리공학회 논문집
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• 제14권2호
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• pp.113-120
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• 2010

장대 아치교 설계 시 시공단계와 완성단계에서 발생할 수 있는 문제에 대하여 검토하고 있으나 케이블 손상에 대한 구조안전성 평가는 매우 미흡한 실정이다. 따라서 본 연구는 공용 중 충돌사고로 인한 행어 파단 시 교량의 구조안전성을 분석하는 것을 연구 목적으로 한다. 이를 위하여 행어 파단에 따른 하중을 충격함수로 이상화하여 동적 해석을 수행하였다. 행어가 파단 되었을 경우 각 행어의 최대 장력은 파단된 행어와 인접한 행어에서 발생한 것으로 나타났으며 정적 하중보다 동적 하중에서 크게 나타났다. 그러므로 장대 아치교의 구조안전성을 확보하기 위해 행어 파단에 따른 충격하중을 동적 하중으로 고려한 해석이 필요하다. 또한 본 연구의 해석 방법 및 결과는 이후 아치교 설계 시 참고자료로 활용될 수 있다.

• Wind and Structures
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• 제19권4호
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• pp.421-441
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• 2014

With the assistance of typhoon field data at aerial elevation level observed by meteorological satellites and wind velocity and direction records nearby the ground gathered in Guangzhou Weather Station between 1985 and 2001, some key wind field parameters under typhoon climate in Guangzhou region were calibrated based on Monte-Carlo stochastic algorithm and Meng's typhoon numerical model. By using Peak Over Threshold method (POT) and Generalized Pareto Distribution (GPD), Wind field characteristics during typhoons for various return periods in several typical engineering fields were predicted, showing that some distribution rules in relation to gradient height of atmosphere boundary layer, power-law component of wind profile, gust factor and extreme wind velocity at 1-3s time interval are obviously different from corresponding items in Chinese wind load Codes. In order to evaluate the influence of typhoon field parameters on long-span flexible bridges, 1:100 reduced-scale wind field of type B terrain was reillustrated under typhoon and normal conditions utilizing passive turbulence generators in TJ-3 wind tunnel, and wind-induced performance tests of aero-elastic model of long-span Guangzhou Xinguang arch bridge were carried out as well. Furthermore, aerodynamic admittance function about lattice cross section in mid-span arch lib under the condition of higher turbulence intensity of typhoon field was identified via using high-frequency force-measured balance. Based on identified aerodynamic admittance expressions, Wind-induced stochastic vibration of Xinguang arch bridge under typhoon and normal climates was calculated and compared, considering structural geometrical non-linearity, stochastic wind attack angle effects, etc. Thus, the aerodynamic response characteristics under typhoon and normal conditions can be illustrated and checked, which are of satisfactory response results for different oncoming wind velocities with resemblance to those wind tunnel testing data under the two types of climate modes.