• Title/Summary/Keyword: Reconstructed space

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A Study on Aerial Triangulation from Multi-Sensor Imagery

  • Lee, Young-Ran;Habib, Ayman;Kim, Kyung-Ok
    • Korean Journal of Remote Sensing
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    • v.19 no.3
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    • pp.255-261
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    • 2003
  • Recently, the enormous increase in the volume of remotely sensed data is being acquired by an ever-growing number of earth observation satellites. The combining of diversely sourced imagery together is an important requirement in many applications such as data fusion, city modeling and object recognition. Aerial triangulation is a procedure to reconstruct object space from imagery. However, since the different kinds of imagery have their own sensor model, characteristics, and resolution, the previous approach in aerial triangulation (or georeferencing) is purformed on a sensor model separately. This study evaluated the advantages of aerial triangulation of large number of images from multi-sensors simultaneously. The incorporated multi-sensors are frame, push broom, and whisky broom cameras. The limits and problems of push-broom or whisky broom sensor models can be compensated by combined triangulation with other sensors The reconstructed object space from multi-sensor triangulation is more accurate than that from a single model. Experiments conducted in this study show the more accurately reconstructed object space from multi-sensor triangulation.

Three-dimensional MHD modeling of a CME propagating through a solar wind

  • An, Jun-Mo;Inoue, Satoshi;Magara, Tetsuya;Lee, Hwanhee;Kang, Jihye;Kim, Kap-Sung;Hayashi, Keiji;Tanaka, Takashi
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.70.2-70.2
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    • 2014
  • We developed a three-dimensional (3D) magnetohydrodynamic (MHD) simulation code to reproduce the structure of a solar wind and the propagation of a coronal mass ejection (CME) through it. This code is constructed by a finite volume method based on a total variation diminishing (TVD) scheme using an unstructured grid system (Tanaka 1994). The grid system can avoid the singularity arising in the spherical coordinate system. In this study, we made an improvement of the code focused on the propagation of a CME through a solar wind, which extends a previous work done by Nakamizo et al. (2009). We first reconstructed a solar wind in a steady state from physical values obtained at 50 solar radii away from the Sun via an MHD tomography applied to interplanetary scintillation (IPS) data (Hayashi et al. 2003). We selected CR2057 and inserted a spheromak-type CME (Kataoka et al. 2009) into a reconstructed solar wind. As a result, we found that our simulation well captures the velocity, temperature and density profiles of an observed solar wind. Furthermore, we successfully reproduce the general characteristics of an interplanetary coronal mass ejection (ICME) obtained by the Helios 1/2 spacecraft (R. J. FORSYTH et al. 2006).

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Splenic Artery Bleeding into the Extraperitoneal Space Mimicking Mesenteric Injury: A Rare Case of Blunt Trauma

  • Seo, Sang Hyun;Jung, Hyun Seok;Park, Chan Yong
    • Journal of Trauma and Injury
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    • v.34 no.2
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    • pp.141-145
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    • 2021
  • Splenic injury is a common result of blunt trauma, and bleeding occurs mainly inside the splenic capsule and may leak into the peritoneal space. Herein, we report a case where active bleeding occurred in the splenic artery and only leaked into the extraperitoneal space. This is the first case of this phenomenon in a trauma patient in the English-language literature. Bleeding passed through the peritoneum, leaked into the anterior pararenal space, and continued along the extraperitoneal space to the prevesical space of the pelvis. Therefore, on the initial computed tomography (CT) scan, the bleeding appeared to be in the left paracolic gutter, so we suspected mesenteric bleeding. However, after the CT series was fully reconstructed, we accurately read the scans and confirmed splenic injury with active bleeding. If there had been a suspicion of bowel or mesenteric injury, surgery would have been required, but fortunately surgery could be avoided in this case. The patient was successfully treated with angioembolization.

A Development of Semi-automatic Trawl-net Surfaces Reconstruction System using Motion Equations and User Interactions (운동 방정식과 사용자 상호작용을 적용한 반자동 트롤 그물 표면 재구축 시스템 개발)

  • Yoon, Joseph;Park, Keon-Kuk;Kwon, Oh-Seok;Kim, Young-Bong
    • Journal of Korea Multimedia Society
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    • v.20 no.8
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    • pp.1447-1455
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    • 2017
  • In a trawl-net simulation, it is very important to process the physical phenomenons resulting from real collisions between a net and fishes. However, because it is very difficult to reconstruct the surface with mass points, many researchers have generally detect the collision using an approximation model employing a sphere, a cube or a cylinder. These approaches occur often result in inaccurate movements of a fish due to the difference between a real-net and a designed-net. So, many systems have manually adjusted a net surface based on actual measurements of mass points. These methods are very inefficient because it needs much times in an adjustment and also causes more incorrect inputs according to a rapid increment in the number of points. Therefore, in this paper, we propose a reconstruction method that it semi-automatically reconstructed trawl-net surfaces using the equation of motion at each mass point in a mass-spring model. To get an easy start in a beginning step of the spread, it enables users to get interactive adjustment on each mass point. We had designed a trawl-net model using geometrical structures of trawl-net and then automatically reconstructed the trawl-net surface using scale-space meshing techniques. Last, we improve the accuracy of reconstructed result by correction user interaction.

The Importance of a Conchal Bowl Element in the Fabrication of a Three-Dimensional Framework in Total Auricular Reconstruction

  • Kim, Young Soo
    • Archives of Plastic Surgery
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    • v.40 no.3
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    • pp.192-197
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    • 2013
  • Background To construct a sophisticated three-dimensional framework, numerous modifications have been reported in the literature. However, most surgeons have paid little attention to the anatomical configuration of the concha and more to its deepness and hollowness, leading to unsatisfactory outcomes. Methods For a configuration of the concha that is definitely anatomical, the author further developed and employed the conchal bowl element, which has been used by several surgeons although the results have not been published elsewhere. The author constructed the conchal bowl element in one of three patterns according to the amount of available cartilages: one block, two-pieces, or a cymba bowl element only. A total of 20 patients underwent auricular reconstruction using a costal cartilage framework between 2009 and 2012. The 8 earliest reconstructions were performed without a conchal bowl element and the latter 12 with a conchal bowl element. The patients were followed up for more than 1 year. The aesthetic results were scored by evaluating characteristics involving the stability of the crus helicis, the conchal definition, and the smoothness of the helical curve. Results The ears reconstructed early without a conchal bowl element showed a shallow and one or two incompletely separated concha with an obliterated cymba conchal space. They also did not have a realistic or smooth curve of the helix because of an unstable crus helicis. However, ears reconstructed later with the concha bowl element showed a definite crus helicis, deep cymba conchal space, and smooth helical curve. Conclusions The construction of the conchal bowl element is simple, not time-consuming procedure. It is suggested that the conchal bowl element must be constructed and attached to the main framework for natural configuration of the reconstructed ear.

A Study on the Transformation of Traditional Urban Space - Focused on Parking Space and Change of Building Use - (일본 전통적 도시공간의 경관변용에 관한 연구 - 주차장소와 용도변경의 분석을 중심으로 -)

  • 김홍기
    • Journal of the Korean housing association
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    • v.14 no.4
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    • pp.87-95
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    • 2003
  • Recently, the traditional urban space has been transformed gradually by the renovation due to increased acquisition of cars and change of building use. This study deals with the transformation of traditional urban space. This contents of this paper as follows. 1)Based on a questionnaire distributed to residents of the Hachiman preservation district, it analyzes actual condition of the possession of cars and its parking spaces. And it shows how traditional houses have been repaired and reconstructed due to the increased acquisition of cars and as a result how the townscape has been transformed. 2) Based on field survey in 1999 and detail map from 1977 to 1999 in Sanneizaka preservation district, it analyzed the change in building use since 1976(when this area was designated as preservation district). It was discovered that the renovation for the building use has been a considered influence on the transformation of the townscape.

A Study on the Establishment of the Spatial Information Platform for the Presumption of Old Urban Space - Based on the Annals of the Joseon Dynasty and the Great Map of Seoul - (도시공간의 옛모습 추정을 위한 공간정보 플랫폼 구축 방안 연구 - 조선왕조실록과 도성대지도를 바탕으로 -)

  • Choi, Mu-Yong
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.9
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    • pp.107-115
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    • 2018
  • It is a basic study to speculate the old form of urban space. The purpose of the study is to study how to build a database that can synthesize multiple data describing the past. In particular, It was focused to the first half time of Seoul City during the Chosun Dynasty. Data is structured systematically and inclusively through digitizing, visualization, and specification. Through this, the city's urban space scene is reconstructed as a map of the city. And maps include various humanities information explaining the aspects of space activities. And it will become a system that will facilitate data management and improve the clarity of information.

Stability Analysis of the Magnetic Structures Producing an M6.5 Flare in active region 12371

  • Kang, Jihye;Inoue, Satoshi;Kusano, Kanya;Park, Sung-Hong;Moon, Yong-Jae
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.41.1-41.1
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    • 2019
  • The stability analysis of coronal magnetic structures is important for studying the initiation of solar flares and eruptions. In order to understand the flare onset process, we first reconstructed the 3D coronal magnetic structures of active region 12371 with an M6.5 flare using a nonlinear force-free field (NLFFF) model based on vector magnetic fields. The NLFFFs successfully produce the observed sigmoidal structure which is composed of two branches of sheared arcade loops. The stability analysis were examined for three representative MHD instabilities: the kink, the torus, and the double arc instabilities. Our stability analysis shows that the two branches of sheared arcade loops are quite stable against the kink and torus instabilities, but unstable against the double arc instability before the flare occurrence. Finally, we discuss a probable onset process of the M6.5 flare.

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Classification of Sides of Neighboring Vehicles and Pillars for Parking Assistance Using Ultrasonic Sensors (주차보조를 위한 초음파 센서 기반의 주변차량의 주차상태 및 기둥 분류)

  • Park, Eunsoo;Yun, Yongji;Kim, Hyoungrae;Lee, Jonghwan;Ki, Hoyong;Lee, Chulhee;Kim, Hakil
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.1
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    • pp.15-26
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    • 2013
  • This paper proposes a classification method of parallel, vertical parking states and pillars for parking assist system using ultrasonic sensors. Since, in general parking space detection module, the compressed amplitude of ultrasonic data are received, the analysis of them is difficult. To solve these problems, in preprocessing state, symmetric transform and noise removal are performed. In feature extraction process, four features, standard deviation of distance, reconstructed peak, standard deviation of reconstructed signal and sum of width, are proposed. Gaussian fitting model is used to reconstruct saturated peak signal and discriminability of each feature is measured. To find the best combination among these features, multi-class SVM and subset generator are used for more accurate and robust classification. The proposed method shows 92 % classification rate and proves the applicability to parking space detection modules.

SUB-Y-TYPE ANTENNA ARRAY CONFIGURATION FOR HIGH RESOLUTION INTERFEROMETRIC SYNTHETIC APERTURE RADIOMETER

  • Kang, Gum-Sil;Jiang, Jingshan;Kim, Yong-Hoon
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.581-586
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    • 2002
  • The development of 2-D radiometer is a new technical challenge for space borne remote sensing area. The Y-type antenna array has been proposed as a most efficient configuration because a large alias free FOV and a small-synthesized beam-width can be achieved compared to L-, T-type under the fixed antenna spacing. New configuration of antenna array, which is called sub-Y type configuration, is proposed to obtain a higher angular resolution than the case of Y-type array in the paper. The sub-Y type array is consisted of basic arrays, which are the Y-type array of four antenna elements. To analyze characteristics of the proposed configuration, the synthesized beam pattern is simulated through simulation. The secondary effect of the sub-Y-type is that the reconstructed image is suffered from the alias effect is appeared around the real target. The ghost targets in the reconstructed image can be reduced by the alias suppression algorithm introduced in this paper. In conclusion, the performance evaluation by use of array factor simulation shows more than 37.5% improvement in average for angular resolution and almost similar performance for temperature resolution.

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