• Title/Summary/Keyword: 사진계측

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Development of Stereoscopic Surface Image Velocimetry using Photogrammetric Techniques (사진 측정 기법을 이용한 스테레오 표면영상유속계의 개발)

  • Yu, Kwon-Kyu;Kim, Dae-Gon;Yoon, Byung-Man
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1799-1803
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    • 2008
  • 표면영상유속계는 하천 표면의 영상을 분석하여 유속을 산정하는 매우 실용적이며 간편한 장비이다. 그러나, 표면영상유속계를 이용하여 유량을 산정하고자 할 경우, 하천 표면의 평면 측량 자료와 하천의 단면 측량 자료가 반드시 필요하다. 이 때문에 표면영상유속계의 간편성과 유용성에도 불구하고, 이용자들이 쉽게 이용하기 어렵다는 그릇된 인식을 줄 수 있다. 만일 효율적이고 간편하게 하천의 단면을 추정할 수 있다면, 표면영상유속계를 마치 일반적인 프로펠러 유속계처럼 쉽게 이용할 수 있을 것이다. 이 연구는 일반적인 평면 측량없이, 두 대의 비디오 카메라로 이루어진 표면 영상 유속계를 이용하여 하천 평면을 계측하는 방법을 개발하는 것이다. 이를 통하여 표면 영상 분석 과정을 반자동화할 수 있게 된다. 두 대의 카메라를 이용한 평면 측량은 사진 측량 분야이나 컴퓨터 비전 분야에서 오랫 동안 연구되어 왔다. 이 기법을 표면영상유속계에 적용함으로써 간단하게 하천의 평면 좌표를 구할 수 있도록 하였다. 두 대의 카메라에 대해서는 직접 선형 변환법을 이용하여 내부 표정과 외부 표정을 수행하여 변환의 매개 변수들을 추정하였다. 추정된 변수들과 공간 전방 교회법을 이용하여 하천의 고정된 기준점들의 좌표를 측정한다. 측정된 좌표점들은 기울어진 영상을 연직으로 사영된 평면으로 변환하는 데 이용되며, 이 과정을 통하여 번거로운 하천의 평면 측량 과정을 생략할 수 있게 되었다. 온천천에 실제 적용하여 본 결과, 결과는 아직은 만족할 만한 정도는 아니나, 보다 정밀한 카메라의 보정 등을 통하여 보다 나은 결과를 도출할 수 있을 것으로 기대된다.

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The Influence of gender or culture on determining esthetic facial profile (심미적 측모 판단에 미치는 성별과 문화의 영향력)

  • Ko, Su-Jin;Kim, Hyun-Soon;Kim, Young-Jin
    • The korean journal of orthodontics
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    • v.31 no.3 s.86
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    • pp.301-309
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    • 2001
  • Because many of patients seeking orthodontic treatment worry about the facial appearance and their chief motivation for orthodontic treatment is facial esthetics, it is critical to understand the influence of gender or culture on the evaluation of profile esthetics. The purpose of this study was to find out any influence of gender or culture on judging good facial profile. 4 different groups were asked to evaluate 133 facial profiles to test the influence of gender or culture on judging good facial profiles. Those 4 groups consisted of 10 Korean males, 10 Korean females, 10 Korean American males, and 10 Korean American females. 2 evaluation systems were introduced, absolute and relative. Soft tissues of selected good profile group were analyzed and statistic analysis was performed. Conclusions were as follows 1. Inter-evaluator difference for judging good facial profile was statistically significant, even if there was general agreement for the best profile among 40 raters. 2. Gender difference under the same cultural environment was not significant statistically. 3. The same ethnic groups with different cultural background showed statistically different preference on judging good Profile. 4. Good facial profile group had their own characteristics compared to remaining group in several soft tissue measurements which were vertical facial ratio, soft tissue facial convexity, and antero-posterior relative lip position.

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A Study on the Pile Behaviour Adjacent to Tunnel Using Photo Imaging Process and Numerical Analysis (Photo Imaging Process 기법 및 수치해석을 이용한 터널주변 파일기초거동에 대한 연구)

  • Lee Yong-Joo
    • Journal of the Korean Geotechnical Society
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    • v.21 no.9
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    • pp.87-102
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    • 2005
  • In the congested urban areas, tunnelling close to existing structures or services often occurs due to the lack of surface space so that tunnelling-induced ground movements may cause a serious damage to the adjacent structures. This study focused on the two dimensional laboratory model pile-soil-tunnelling interaction tests using a close range photogrammetric technique. Testing equipments and procedures were Introduced, particularly features of aluminium rods regarded as the frictional granular material. The experimental result showed that the photo imaging process by the VMS and EngVis programs proved to be a useful tool in measuring the pile tip movements during the tunnelling. Consequently, the normalised pile tip movement data for the influence zones can be generated by the laboratory model tests using the Photogrammetric technique. This study presents influence zones associated with the normalized pile tip settlements due to tunnelling in the cohesionless material. The influence zones were Identified by both a laboratory model test and a numerical analysis. The normalized pile tip movements from the model test were in good agreement with the numerical analysis result. The influence zones proposed in this study could be used to decide the reasonable location of tunnel construction in the planning stage. However, the scale of model pile and model tunnel sizes must be carefully adjusted as real ones for practical application considering the ground conditions at a given site.

What determines dental protrusion or crowding while both malocclusions are caused by large tooth size? (치아전돌자와 치아밀집자의 측모두부방사선학적 비교)

  • Sun, Min-Kyu;Kim, Jae-Hyung;Cho, Jin-Hyoung;Kim, Jeong-Moon;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.39 no.5
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    • pp.330-336
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    • 2009
  • Objective: To examine the differences in lateral cephalometric characteristics between patients with dental protrusion and crowding in order to determine what factors affect dental protrusion or crowding while both malocclusion types are caused by large tooth size. Methods: Twenty nine individuals with dental protrusion and 22 individuals with dental crowding were enrolled in this study. All subjects had larger teeth than average and Class I molar relationships. Craniofacial characteristics and hyoid bone positions were determined from lateral cephalograms and compared between the two groups. Results: In the comparisons of craniofacial characteristics, the measurements indicating maxillary length and facial convexity showed greater values in the protrusion group than in the crowding group. Comparisons of hyoid bone positions showed that the hyoid bone was positioned more anteriorly and superiorly in the protrusion group than in the crowding group. Conclusions: The results of the present study indicate that some craniofacial characteristics and tongue position may affect the development of dental protrusion or crowding; when an individual has large teeth, dental protrusion or crowding might be determined according to maxillary growth and tongue position.

Pile and adjacent ground behaviors depending on horizontal offset between pile and tunnel subjected to horizontally loaded single pile (수평하중을 받는 단일 말뚝 하부 터널굴착 시 말뚝-터널 수평이격거리에 따른 말뚝 및 인접 지반 거동)

  • Ahn, Ho-Yeon;Oh, Dong-Wook;Lee, Yong-Joo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.5
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    • pp.685-703
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    • 2017
  • Recently, as the number of high-rise building and earthquake occurrence are increasing, it is more important to consider horizontal load such as wind and seismic loads, earth pressure, for the pile foundation. Also, development of underground space in urban areas is more demanded to meet various problem induced by growing population. Many studies on pile subjected to horizontal load have been conducted by many researchers. However, research regarding interactive behavior on pile subjected to horizontal load with tunnel are rare, so far. In this study, therefore, study on the behaviors of ground and horizontal and vertical loads applied to single pile was carried out using laboratory model test and numerical analysis. The pile axial force and ground deformation were investigated according to offset between pile and tunnel (0.0D, 1.0D, 2.0D: D = tunnel diameter). At the same time, close range photogrammetry was used to measure displacement of underground due to tunnelling during laboratory model test. The results from numerical analysis were compared to that from laboratory model test.

A Roentgenocephalometric Study on the Relationship of His' Line to the Upper and Lower Face (His선(線)과 상하안모(上下顔貌) 관계(關係)에 관(關)한 두부방사선(頭部放射線) 계측학적(計測學的) 연구(硏究))

  • Bae, Chang
    • The Journal of Korean Academy of Prosthodontics
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    • v.8 no.1
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    • pp.65-71
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    • 1968
  • 저자(著者)는 성장(成長) 발육기(發育期)에 있는 한국인(韓國人)의 His' line과 전두기저선(前頭基底線) 안이평면(眼耳平面) 하악평면(下顎平面) 구개평면(口蓋平面)이 이루는 각도적(角度的) 변화(變化)를 관찰(觀察)하기 위하여 정당교합인(正當咬合人) 남(男) 여(女) 195명(名)의 두부방사선규격사진(頭部放射線規格寫眞)을 Hellma의 치령 분류법(齒齡 分類法)에 의(依)하여 분류(分類)하고 계측(計測) 관찰(觀察)하였든바 다음과 같은 결과(結果)를 얻었다. 1. 성장(成長) 발육기(發育期)에 있어서 전두기저선(前頭基底線)과 His' line이 일정(一定)한 각도(角度) 관계(關係)를 유지한다. 2. His' line은 수평성장축(水平成長軸)으로 생각(生覺)할 수 있다. 3. His' line은 구개평면(口蓋平面)과 대부분(大部分) 일치(一致)하며 남녀(男女)에는 별 차이(差異) 없다. 4. 하악평면(下顎平面)과 His' line이 이루는 각(角)이 심한 것으로 보아 강(强)한 경사도(傾斜度)를 나타내고 있다. 5. 서양인(西洋人)에 비해 하악골(下顎骨)의 후퇴(後退)를 볼 수있다.

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The Effect of Mouth Breathing Due to Nasopharyngeal Obstruction by Adenoids on the Tongue, Mandible and Hyoid Bone Position (Adenoids의 비인두폐쇄로 인한 구호흡이 Tongue, Mandible 및 Hyoid Bone의 위치에 미치는 형향)

  • Lee, Hee-Kyoung
    • Journal of Yeungnam Medical Science
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    • v.5 no.2
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    • pp.71-77
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    • 1988
  • This study was made to investigate the influence of mouth breathing to tongue, mandible and hyoid bone position. It has been clinically suggested that the mouth breathing is induced by the respiratory dysfunction of nasopharyngeal airway causing by the Adenoids. The author used the 50 children, who were the nasal breathes with normal occlusion as the control group, and 50 children, who were mouth breathers with Adenoid as the experimental group. Results were as following: 1. In experimental group, the tongue was positioned more anterior and lower than that of the normal children. 2. In experimental group, the mandible was positioned more lower than that of the normal children. 3. In experimental group, the hyoid bone was positioned more anterior and lower than that of the normal children.

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AN ANALYSIS OF SOFT TISSUE PROFILE (연조직 측모에 관한 분석)

  • Chang, Young-Il;Choi, Hee-Young;Shin, Soo-Jung
    • The korean journal of orthodontics
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    • v.25 no.5 s.52
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    • pp.627-634
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    • 1995
  • The purpose of this study to analyze characteristics of soft tissue profile in Korean young adults. The sample consisted of 50 young adults (25 males and B females) who had pleasing and normal occlusion. Soft tissue analysis (facial convexity angle, nasolabial angle, H-angle, Z-angle, E-line to upper lip, lower lip, Sn-pog' to upper lip, lower lip) was performed on lateral cephlograms. Mem and standard deviation was obtained. When compared by other studies, mean profile of this sample was relatively straighter and both the upper and lower lips was more protrusive.

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Soft tissue cephalometric analysis of Aesthetic Korean female (심미적 측모에 관한 두부계측방사선학적 연구)

  • Kim, Yoon-Ji;Nahm, Dong-Seok
    • The korean journal of orthodontics
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    • v.32 no.6 s.95
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    • pp.383-393
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    • 2002
  • The purpose of this study was to provide data on the normative values of some clinically important soft tissue dimensions for adult Korean females with aesthetically beautiful facial profiles. Lateral cephalograms of 18 Korean female models, who were selected for their well balanced and aesthetic facial profiles, were evaluated. All cephalograms were taken with the subjects in a natural head position with the teeth in occlusion and the lips at rest. The means and standard deviations were determined and presented. In addition, comparisons with the previous studies were performed The results of the present study were as follows: 1. The upper and lower lips were posteriorly located in relation to the Ricketts' E line (Upper lip to E line: -2.08, Lower lip to E line: -0.04). 2. Both lips were more posteriorly located than those in the results of previous studies on Korean females selected by normal occlusion, but more anteriorly located than in the results of studies selected on an aesthetic basis. 3. The nasolabial angle for this sample was 101.03 degrees with a standard deviation of 8.47 degrees.

DEVELOPMENT OF THREE DIMENSIONAL MEASURING PROGRAM WITH FRONTAL AND LATERAL CEPHALOMETRIC RADIOGRAPHS -PART 2. 3-D VISUALIZATION AND MEASURMENT PROGRAM FOR MAXILLOFACIAL STRUCTURE- (정모 및 측모 두부 방사선 규격사진을 이용한 3차원 계측 프로그램의 개발 -2. 악안면 구조에 대한 3차원적 시각화 및 측정프로그램 개발-)

  • Lee, Sang-Han;Mori, Yoshihide;Minami, Katsuhiro;Lee, Geun-Ho;Kwon, Tae-Geon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.4
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    • pp.321-329
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    • 2001
  • To establish systematic diagnosis and treatment planning of dentofacial deformity patient including facial asymmetry or hemifacial microsomia patient, comprehensive analysis of three dimensional structure of the craniofacial skeleton is needed. Even though three dimensional CT has been developed, landmark identification of the CT is still questionable. In recent, a method for correcting cephalic malpositioning that enables accurate superimposition of the landmarks in different stages without using any additional equipment was developed. It became possible to compare the three-dimensional positional change of the maxillomandible without invasive procedure. Based on the principle of the method, a new program was developed for the purpose of diagnosis and treatment planning of dentofacial deformity patient via three dimensional visualization and structural analysis. This program enables us to perform following menu. First, visualization of three dimensional structure of the craniofacial skeleton with wire frame model which was made from the landmarks observed on both lateral and frontal cephalogram. Second, establishment of midsagittal plane of the face three dimensionally, with the concept of "the plane of the best-fit". Third, examination of the degree of deviation and direction of deformity of structure to the reference plane for the purpose of establishing surgical planning. Fourth, simulation of expected postoperative result by various image operation such as mirroring, overlapping.

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