• Title/Summary/Keyword: 3D planning

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Usefullness with 3D CT Angiography in Microsurgical Reconstruction (미세수술을 이용한 하지의 재건시 삼차원 컴퓨터 혈관조영술의 유용성)

  • Sung, Yong Duck;Kim, Hyo Heon
    • Archives of Plastic Surgery
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    • v.33 no.2
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    • pp.175-180
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    • 2006
  • Preoperative angiography is frequently used in the planning of microsurgical reconstruction for identification of vascular abnormality that influence the planning of operation. But, recently 3D CT angiography is considered as new technique that can provide detailed information about vascular anatomy as well as soft and bony tissue without the risks of invasive angiography. 3D CT angiograms were performed in 19 patients before microsurgical reconstruction for the lower extremity and hand between May of 2003 and Oct of 2004. Sixteen of the studies were of the donor site and all of 19 studies were of the recipient site. No complications were found from the 3D CT angiograms. In one case of the bone exposed open wound, the injury of anterior tibial artery was identified and the zone of injury was adequately demonstrated. With the improvement in quality of CT imaging, 3D CT angiograms may provide a favorable alternative to invasive angiography. It is capable of providing high-resolution, three dimensional vascular imaging without the need for arterial puncture and prolonged post-procedure observation. The relation among blood vessels, bones, and soft tissue is well demonstrated in 3D CT angiogram. Also The acquisition time and examination cost were considerably lower in comparison with invasive angiography. In conclusion, this study demonstrates that 3D CT angiography may provide accurate, safe, and cost-effective preoperative imaging. The 3D CT angiography with relatively low morbidity, low cost, ease of image acquisition can have an broader role in microsurgical reconstructive surgery.

Spatial Analysis of the Urban Heat Island Using a 3-D City Model (3차원 도시모형을 이용한 도시열섬의 공간분석)

  • Chun, Bum-Seok;Guldmann, Jean-Michel
    • Spatial Information Research
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    • v.20 no.4
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    • pp.1-16
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    • 2012
  • There is no doubt that the urban heat island (UHI) is a mounting problem in built-up environments, due to energy retention by the surface materials of dense buildings, leading to increased temperatures, air pollution, and energy consumption. To investigate the UHI, three-dimensional (3-D) information is necessary to analyze complex sites, including dense building clusters. In this research, 3-D building geometry information is combined with two-dimensional (2-D) urban surface information to examine the relationship between urban characteristics and temperature. In addition, this research introduces spatial regression models to account for the spatial spillover effects of urban temperatures, and includes the following steps: (a) estimating urban temperatures, (b) developing a 3-D city model, (c) generating urban parameters, and (d) conducting statistical analyses using both Ordinary Least-Squares (OLS) and Spatial Regression Models. The results demonstrate that 3-D urban characteristics greatly affect temperatures and that neighborhood effects are critical in explaining temperature variations. Finally, the implications of the results are discussed, providing guidelines for policies to reduce the UHI.

A Web-based Spatial Layout Planning System with Constraint Satisfaction Problems (웹 환경 하에서의 제약 만족 기법에 의한 공간 계획 시스템)

  • Jung, Jae-Eun;Jeon, Seung-Bum;Jo, Geun-Sik
    • Journal of KIISE:Computing Practices and Letters
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    • v.6 no.2
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    • pp.216-224
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    • 2000
  • The spatial layout planning system allocates rectangular resources in the limited space according to user requirements, This system also can optimizes the spatial allocation problem to maximize the user's requirement. The spatial layout planning Problems for this system can be solved by searching a wide area of space since this problem entails the non-polynomial algorithm. By accommodating the user's dynamic requirements, the modification of a specific space and the redesign of the whole area can be accomplished. In this paper, the spatial layout planning problem is solved efficiently with a resource allocation method based on CSP. The dynamic constraints by adding user requirements are accommodated through the intelligent user Interface. The 3-D layout on the web environment by using VRML is also shown for providing for the visual verification of the 2-D layout and, thereafter, the additional modification of the 2-D layout.

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Image Guided Brachytherapy in Cervix Cancer

  • Park, Sung-Yong;Shin, Kyung-Hwan;Park, Dahl;Cho, Jung-Keun;Kim, Dae-Yong;Kim, Jong-Won;Cho, Kwan-Ho;Kim, Tae-Hyun;Chie, Eui-Kyu
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.154-156
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    • 2002
  • Brachytherapy has a long history in the treatment of cancer. However, the treatment planning technique for brachytherapy has lagged somewhat behind the corresponding developments for external beam therapy as far as the imaging technique is concerned. Currently, the orthogonal-film-based treatment planning is performed at most institutions even though the CT-based planning is available. The aim of this study is to evaluate the CT-based vs. the orthogonal-film-based treatment planning in cervix cancer. The doses to point A, point B, rectum and bladder points according to ICRU 38 were calculated for the two methods above. In addition, the volumetric studies such as 3D dose computation and DVH were obtained for the CT-based planning. For the bulky tumor, the isodose lines of point A prescription were not fairly covered for the CTV. The CT -based dose planning can overestimate the maximum dose delivered to bladder and rectum by 30%. The CT-based planning has several advantages over the orthogonal-film-based such as 3D dose display, DVH, and more accurate target delineation. It is suggested that the prescription point in cervix cancer be revised especially for the bulky tumor.

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Development of an Approximate Cost Estimating Framework for River Facility Construction at Planning Stage (하천시설물 공사의 기획단계 개략공사비 산정체계 개발)

  • Shin, Jung Min;Woo, Sungkwon;Lee, Si Wook;Kim, Ok Ki
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3D
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    • pp.371-381
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    • 2008
  • The systematic methodology for estimating construction cost approximately at planning and pre-design phase of a river facility construction project has not yet been established because of its unique characteristics including its relatively small project size in terms of cost. This research suggests a 4-level cost information structure and identifies critical factors affecting construction cost as a result of thorough analysis of accumulated historical cost data of river facility construction projects. Also, this research presents the framework of the approximate cost estimating methodology for river facility construction project a planning stage.

Hierarchical Fuzzy Motion Planning for Humanoid Robots Using Locomotion Primitives and a Global Navigation Path

  • Kim, Yong-Tae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.3
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    • pp.203-209
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    • 2010
  • This paper presents a hierarchical fuzzy motion planner for humanoid robots in 3D uneven environments. First, we define both motion primitives and locomotion primitives of humanoid robots. A high-level planner finds a global path from a global navigation map that is generated based on a combination of 2.5 dimensional maps of the workspace. We use a passage map, an obstacle map and a gradient map of obstacles to distinguish obstacles. A mid-level planner creates subgoals that help the robot efficiently cope with various obstacles using only a small set of locomotion primitives that are useful for stable navigation of the robot. We use a local obstacle map to find the subgoals along the global path. A low-level planner searches for an optimal sequence of locomotion primitives between subgoals by using fuzzy motion planning. We verify our approach on a virtual humanoid robot in a simulated environment. Simulation results show a reduction in planning time and the feasibility of the proposed method.

A Shortest Path Planning Algorithm for Mobile Robots Using a Modified Visibility Graph Method

  • Lee, Duk-Young;Koh, Kyung-Chul;Cho, Hyung-Suck
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1939-1944
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    • 2003
  • This paper presents a global path planning algorithm based on a visibility graph method, and applies additionally various constraints for constructing the reduced visibility graph. The modification algorithm for generating the rounded path is applied to the globally shortest path of the visibility graph using the robot size constraint in order to avoid the obstacle. In order to check the visibility in given 3D map data, 3D CAD data with VRML format is projected to the 2D plane of the mobile robot, and the projected map is converted into an image for easy map analysis. The image processing are applied to this grid map for extracting the obstacles and the free space. Generally, the tree size of visibility graph is proportional to the factorial of the number of the corner points. In order to reduce the tree size and search the shortest path efficiently, the various constraints are proposed. After short paths that crosses the corner points of obstacles lists up, the shortest path among these paths is selected and it is modified to the combination of the line path and the arc path for the mobile robot to avoid the obstacles and follow the rounded path in the environment. The proposed path planning algorithm is applied to the mobile robot LCAR-III.

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Analysis of the Regional Dependency Using the O-D Matrix of Commuters (통근 자료를 이용한 시군구 단위 지역종속성 분석 -수도권 및 충청권역을 대상으로-)

  • Lee, Ji-Min;Kim, Tae-Gon;Lee, Jeong-Jae;Suh, Kyo
    • Journal of Korean Society of Rural Planning
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    • v.18 no.3
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    • pp.165-174
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    • 2012
  • Development of transportation and communication technology has affected our daily life and has caused to separate residential places from working places. Particularly in rural areas, the life zones are incorporated into larger towns or urban areas due to their lack of cultural, social and economic infrastructures. Thus, the analysis of the depended region and the life zone is important for the planning of regional revitalization programs and related project. The purpose of this study is to propose a regional dependency model (RDM) using the origin-destination(O-D) matrix of commuters and compare it with the Nystuen & Dacey model for regional correlation. The regional characteristics are analysed and our RDM were tested using the commuting data on Seoul metropolitan area(Seoul, Gyeong-gi, Incheon) and Chungchung area. The regional correlation model can only explain the determination of regional interaction without considering the direction of regional correlation but our model can show the direction of regional dependencies.

Volumetric-Modulated Arc Radiotherapy Using Knowledge-Based Planning: Application to Spine Stereotactic Body Radiotherapy

  • Jeong, Chiyoung;Park, Jae Won;Kwak, Jungwon;Song, Si Yeol;Cho, Byungchul
    • Progress in Medical Physics
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    • v.30 no.4
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    • pp.94-103
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    • 2019
  • Purpose: To evaluate the clinical feasibility of knowledge-based planning (KBP) for volumetric-modulated arc radiotherapy (VMAT) in spine stereotactic body radiotherapy (SBRT). Methods: Forty-eight VMAT plans for spine SBRT was studied. Two planning target volumes (PTVs) were defined for simultaneous integrated boost: PTV for boost (PTV-B: 27 Gy/3fractions) and PTV elective (PTV-E: 24 Gy/3fractions). The expert VMAT plans were manually generated by experienced planners. Twenty-six plans were used to train the KBP model using Varian RapidPlan. With the trained KBP model each KBP plan was automatically generated by an individual with little experience and compared with the expert plan (closed-loop validation). Twenty-two plans that had not been used for KBP model training were also compared with the KBP results (open-loop validation). Results: Although the minimal dose of PTV-B and PTV-E was lower and the maximal dose was higher than those of the expert plan, the difference was no larger than 0.7 Gy. In the closed-loop validation, D1.2cc, D0.35cc, and Dmean of the spinal cord was decreased by 0.9 Gy, 0.6 Gy, and 0.9 Gy, respectively, in the KBP plans (P<0.05). In the open-loop validation, only Dmean of the spinal cord was significantly decreased, by 0.5 Gy (P<0.05). Conclusions: The dose coverage and uniformity for PTV was slightly worse in the KBP for spine SBRT while the dose to the spinal cord was reduced, but the differences were small. Thus, inexperienced planners could easily generate a clinically feasible plan for spine SBRT by using KBP.

A Study on Implementation and Deriving Future Tasks of 「The Korean National CCS Master Action Plan」 (「국가 CCS 종합추진계획」 이행점검 및 개선과제 도출 연구)

  • Cho, GaBi;Cho, Hayoung;Park, Noeon
    • Journal of Climate Change Research
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    • v.7 no.3
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    • pp.237-247
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    • 2016
  • Global warming caused by greenhouse gases is one of the foremost challenges in the international community. As an alternative to solve this problem, the importance of CCS (Carbon Capture and Storage) technology is increasing. However, due to the delay of European financial crisis recovery, some large-scale CCS projects were postponed. In turn, large-scale CCS projects in South Korea have not been launched as originally planned. Given these situations, it is important to review the latest R&D activities related to CCS in South Korea, and then adjust relevant national policy accordingly. The purpose of this study is to identify policy issues for the effective promotion of CCS technology in South Korea. Following the analysis of recent global trend on CCS policy, we evaluated the results and achievements from national CCS projects, which had been listed under the "Korean National CCS Master Action Plan (2010)". Especially, we tried to review the attainability for the original goal of each project. Through the present study, we identified the current status of CCS technology in South Korea and suggested efficient ways to be taken in order to increase efficiency in implementing national CCS policy in the future.