• Title/Summary/Keyword: Visual Angle

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A Study on Automated Lineament Extraction with Respect to Spatial Resolution of Digital Elevation Model (수치표고모형 공간해상도에 따른 선구조 자동 추출 연구)

  • Park, Seo-Woo;Kim, Geon-Il;Shin, Jin-Ho;Hong, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • 제34권3호
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    • pp.439-450
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    • 2018
  • The lineament is a linear or curved terrain element to discriminate adjacent geological structures in each other. It has been widely used for analysis of geology, mineral exploration, natural disasters, and earthquake, etc. In the past, the lineament has been extracted using cartographic map or field survey. However, it is possible to extract more efficiently the lineament for a very wide area thanks to development of remote sensing technique. Remotely sensed observation by aircraft, satellite, or digital elevation model (DEM) has been used for visual recognition for manual lineament extraction. Automatic approaches using computer science have been proposed to extract lineament more objectively. In this study, we evaluate the characteristics of lineament which is automatically extracted with respect to difference of spatial resolution of DEM. We utilized two types of DEM: one is Shuttle Radar Topography Mission (SRTM) with spatial resolution of about 90 m (3 arc sec), and the other is the latest world DEM of TerraSAR-X add-on for Global DEM with 12 m spatial resolution. In addition, a global DEM was resampled to produce a DEM with a spatial resolution of 30 m (1 arc sec). The shaded relief map was constructed considering various sun elevation and solar azimuth angle. In order to extract lineament automatically, we used the LINE module in PCI Geomatica software. We found that predominant direction of the extracted lineament is about $N15-25^{\circ}E$ (NNE), regardless of spatial resolution of DEM. However, more fine and detailed lineament were extracted using higher spatial resolution of DEM. The result shows that the lineament density is proportional to the spatial resolution of DEM. Thus, the DEM with appropriate spatial resolution should be selected according to the purpose of the study.

THREE-DIMENSIONAL FINITE ELEMENT ANALYSIS OF THE PHENOMENON PRODUCED DURING RETRACTION OF FOUR MAXILLARY INCISORS (상악 4절치의 후방견인시 나타나는 현상에 관한 유한요소법적 분석)

  • Cheon, Ok-Jin;Kim, Tae-Woo;Suhr, Cheong-Hoon
    • The korean journal of orthodontics
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    • 제25권5호
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    • pp.525-541
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    • 1995
  • This study was designed to investigate force systems and tooth movements produced by retraction archwire during retraction of four maxillary incisors after the maxillary canine retraction into the maxillary first premolar extraction space using the computer-aided three-dimensional finite element method. A three-dimensional finite element model, consisting of 2248 elements and 3194 nodes, was constructed. The model consisted of maxillary teeth and surrounding periodontal membranes, .022'$\times$.028'-slot brackets, and 5 types of retraction archwires(.019'$\times$.025' stainless steel archwire) modeled using the beam elements. The contact between the wire and the bracket slot was modeled using the gap elements because of the non-linear elastic behaviors of the contact between them. The forces and moments, End displacements produced by retraction archwire were measured at various conditions to investigate the difference according to types of loops, magnitudes of activation force, gable angle, and anterior lingual root torque. The results were expressed quantitative and visual ways in the three-dimensional method. The following conclusions can be drawn from this study.1. When the tear-drop loop archwire was activated, the mesio-distal and lingual translational movements of the teeth helped to close the extraction space, but unwanted movements of the teeth including intrusions and extrusions, and rotational movements in each direction occurred. 2. Activation of T-loop archwire compared with those of other types of retraction archwires produced the least translational movements of the teeth helped to space closure and also the least unwanted movements of the teeth. 3. Increasing amount of activation in the tear-drop archwire led not only to increase of translational movements of the teeth helped to space closure, but also to increase of unwanted movements of the teeth. 4. Addition of gable bend in the tear-drop archwire helped anterior teeth to translational movements in the mesio-distal direction, but increased unwanted movements of the teeth 5. Addition of anterior lingual root torque in the tear-drop archwire helped central and lateral incisor to improve their facio-lingual inclination, but increased unwanted movements of the teeth.

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Development of Prism Dot-sight Combined with Thermal Imaging Camera (열영상 카메라가 결합된 프리즘 도트사이트 개발)

  • Park, Seung-Hwan;Jung, Bo-Seon;Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • 제19권4호
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    • pp.479-485
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    • 2014
  • Purpose: This study relates to the development of the prism dot-sight combined with the thermal imaging camera. Methods: We have placed a reflector designed to the doublet type in the front of a BS (beam splitting) prism, have placed an OLED panel and a dot reticle generator to the top and bottom of the reflecting surface of the BS prism, and have placed a detachable magnifier between the BS prism and the observer by which the observer can see the magnified image of the OLED panel. By doing this, we were able to configure the new type prism dot-sight combined with the thermal imaging camera. Results: By placing the removable magnifier designed with a new type between the BS prism and the observer, we could design the new type prism dot-sight which performs the role of the dot sight by removing the magnifier during the day-time, and performs the role of the night scope during the night-time by which we can observe the enlarged image of the thermal imaging camera through the BS prism by attaching the removable magnifier. Conclusions: In this study, we have developed the prism dot-sight combined with the thermal imaging camera which is able to play the role of the day or night scope selectively, by disposing the designed magnifier characterized by the focal length of 44 mm, the viewing angle of ${\pm}7.0^{\circ}$, and the MTF value of 0.5 or more at the criterion of 50 lp/mm and the 0.7 field between the BS prism and the observer. By doing so, we could design and fabricate the new type prism dot-sight combined with the thermal imaging camera which can further increase the rapidity of firing and provide more convenience in the mounting of a firearm than the detachable combination of an existing dot sight and an existing night scope.

A Study of Experimental Image Direction for Short Animation Movies -focusing in short film and (단편애니메이션의 실험적 영상연출 연구 -<탱고>와 <페스트 필름>을 중심으로)

  • Choi, Don-Ill
    • Cartoon and Animation Studies
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    • 통권36호
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    • pp.375-391
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    • 2014
  • Animation movie is a non-photorealistic animated art that consists of formative language forming a frame based on a story and cuts describing frames that form the cuts. Therefore, in expressing an image, artistic expression methods and devices for a formative space are should be provided in a frame while cuts have the images between frames faithfully. Short animation movie is produced by various image experiments with unique image expressions rather than narration for expressing subjective discourse of a writer. Therefore, image style that forms unique images and various image directions are important factors. This study compared the experimental image directions of and , both of which showed a production method of film manipulation. First, while uses pixilation that produces images obtained from live images through painting and many optical disclosure process on a cell mat, was made with diverse collage techniques such as tearing, cutting, pasting, and folding hundreds of scenes from action movies. Second, expresses non-causal relationship of characters by their repetitive behaviors and circulatory image structure through a fixed camera angle, resisting typical scene transition. On the other hand, has an advancing structure that progresses antagonistic relationship of characters through diverse camera angles and scene transition of unique images. Third, in terms of editing, uses a long-take short cut technique in which the whole image consists of one short cut, though it seems to be many scenes with the appearance of various characters. On the other hand, maximizes visual fun and commitment by image reconstruction with hundreds of various short cuts. That is, both works have common features of an experimental work that shows expansion of animated image expressions through film manipulation that is different form general animation productions. On top of that, delivers routine life of diverse human beings without clear narration through image of conceptualized spaces. expresses it in a new image space through image reconstruction with collage technique and speedy progress, setting a binary opposition structure.

Comparision of Trans-Tibial and Anteromedial Portal Approach in Femoral Tunneling of Anterior Cruciate Ligament Reconstruction (전방십자인대 재건술의 대퇴골 터널 굴착시 경경골 접근법과 전내측통로 접근법의 비교)

  • Sohn, Sung-Keun;Chang, Yun-Suk;Chung, ll-Kwon;Kim, Kyung-Taek
    • Journal of the Korean Arthroscopy Society
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    • 제8권2호
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    • pp.75-81
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    • 2004
  • Purpose: Recent development and advances in arthroscopic surgical techniques for Anterior Cruciate Ligament(ACL) reconstruction have led to the ideal location for the etric point from 10 o'clock (in right knee) and 13:30 (in left knee) to 10:30 (in right knee) and 14 o'clock (in left knee) in the frontal plane. This study was performed to compare operative methods and the radiologic results of femoral tunnels made through the tibial tunnel(trans-tibial approach) and the anteromedial portal. Material and Methods: From January 2003 to May 2004, one-hundred reconstructions of anterior cruciate ligament were performed. Group I (femoral tunnel through tibial tunnel) was composed of 50 cases and group ll (femoral tunnel through anteromedial portal) was consisted of 50 cases. The study was performed to compare the radiographic results of femoral tunnels made through the tibial tunnel and the anteromedial portal and operative methods. Results: In operative methods at Group II, femoral tunnel was made more easily at isometric point than Group I, a good visual field was achived because 100$^{\circ}$ flxion of knee, they can be reduced risk of posterior cortical breakage and tunnel-graft mismatching and decreased divergence of femoral interference screw in radiology (P<0.05). The angle between femoral tunnel and longitudinal axis of ACL wae increased at Group ll. Conclusion: Aanteromedial portal technique was more useful in ACL reconstruction for femoral tunnel toward 10 o'clock to10:30(in right) or 1:30 to 2 o'clock(in left).

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The Location and Landscape Composition of Yowol-pavilion Garden Interpreted from Tablet & Poetry (편액과 시문으로 본 요월정원림(邀月亭園林)의 입지 및 조영 해석)

  • Lee, Hyun-Woo;Kim, Sang-Wook;Ren, Qin-Hong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • 제32권3호
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    • pp.32-45
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    • 2014
  • The study attempts to interpret original location and landscape composition of Yowol-pavilion Garden under the premise that tablet and poetry are important criteria for inference of unique location and landscape composition of a pavilion garden. The study raises the meaning, status, and value of Yowol Pavilion Garden as a cultural asset. The results of the study are as follows. First, Yowol-pavilion Garden was a place where famous Confucius scholars in Joseon Dynasty in 16th Century, including Kim, Kyung-Woo, the owner of the garden, used to share the taste for the arts and poetries with their colleagues. Along with a main characteristic of Yowol Pavilion Garden as a hideout for the Confucius scholars who stayed away from a political turmoil, the new place characteristic of the garden, a bridgehead for the formation of regional identity, was discovered in the record of "Joseon-Hwanyeo-Seungram Honam-Eupji JangSeong-Eupji", As described in "The first creative poetry of Yowol-pavilion", the intention for the creation of Yowol-pavilion Garden and the motive for its landscape composition is interpreted as a space of rivalry where the world, reality and ideals are mixed up. Second, related to outstanding scenic factors and natural phenomena when taking a view from the pavilion, the name of the house 'Yowol', which means 'Greeting the moon rising on the Mt. Wolbong' is the provision of nature and taste for the arts, and is directly connected to the image of leaving the worldly. In other words, the name was identified to be the one that reflected the intention for landscape composition to follow the provision of nature separating from joy and sorrow of the mundane world. Third, as for the location, it was confirmed through "YeongGwang-Soksu-Yeoji-Seungram" that Yowol-pavilion Garden was a place where the person who made the pavilion prepared for relaxation after stepping down from a government post, and literature and various poetry show that it was also a place of outstanding scenic where Yellow-dragon River meandered facing Mt. Wolbong. Especially, according to an interview with a keeper, the visual perception frequency of the nightscape of Yowol-pavilion Garden is the highest when viewing by considering the east, the direction of Yellow-dragon River, as Suksigak[normal angle's view], towards Yowel-pavilion from the keeper's house. In addition, he said that the most beautiful landscape with high perception strength is when the moon came up from the left side of Yowol-pavilion, cuts across the Lagerstroemia india heal in front of Yowol-pavilion, and crosses the meridian between Mt. Wolbong peaks facing Yowol-pavilion. Currently, the exposure of Yowol-pavilion Garden is $SE\;141.2^{\circ}$, which is almost facing southeast. It is assumed that the exposure of Yowol-pavilion Garden was determined considering the optimized direction for appreciating the trace of the moon and the intention of securing the visibility as well as topographic conditions. Furthermore, it is presumed that the exposure of Yowol-pavilion Garden was determined so that the moon is reflected on the water of Yellow-dragon River and the moon and its reflection form a symmetry. Fourth, currently, Yowol-pavilion Garden is divided into 'inner garden sphere' composed of Yowol-pavilion, meeting place of the clan and administration building, and 'outer garden sphere' which is inclusive of entrance space, Crape Myrtle Community Garden and Pine Tree Forest in the back. Further, Yowol-pavilion Garden has been deteriorated as the edge was expanded to 'Small lake[Yong-so] and Gardens of aquatic plants sphere' and recently-created 'Yellow-dragon Pavilion and park sphere'. Fifth, at the time it was first made, Yowol-pavilion Garden was borderless gardens consisting of mountains and water taking a method of occupying a specific space of nearby nature centering around pavilion by embracing landscape viewed from the pavilion, but interpreted current complex landscapes are identified to be entirely different from landscapes of the original due to 'Different Changes', 'Fragmentation' and 'Apart piece' in many parts. Lastly, considering that Yowol-pavilion Garden belongs to the Cultural Properties Protection Zone, though not the restoration to the landscapes of the original described in tablet and literature record, at least taking a measure from the aspect of land use for minimizing adverse effect on landscape and visual damage is required.