• 제목/요약/키워드: Volume rendering high

검색결과 55건 처리시간 0.023초

DESIGN AND IMPLEMENTATION OF 3D TERRAIN RENDERING SYSTEM ON MOBILE ENVIRONMENT USING HIGH RESOLUTION SATELLITE IMAGERY

  • Kim, Seung-Yub;Lee, Ki-Won
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.417-420
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    • 2006
  • In these days, mobile application dealing with information contents on mobile or handheld devices such as mobile communicator, PDA or WAP device face the most important industrial needs. The motivation of this study is the design and implementation of mobile application using high resolution satellite imagery, large-sized image data set. Although major advantages of mobile devices are portability and mobility to users, limited system resources such as small-sized memory, slow CPU, low power and small screen size are the main obstacles to developers who should handle a large volume of geo-based 3D model. Related to this, the previous works have been concentrated on GIS-based location awareness services on mobile; however, the mobile 3D terrain model, which aims at this study, with the source data of DEM (Digital Elevation Model) and high resolution satellite imagery is not considered yet, in the other mobile systems. The main functions of 3D graphic processing or pixel pipeline in this prototype are implemented with OpenGL|ES (Embedded System) standard API (Application Programming Interface) released by Khronos group. In the developing stage, experiments to investigate optimal operation environment and good performance are carried out: TIN-based vertex generation with regular elevation data, image tiling, and image-vertex texturing, text processing of Unicode type and ASCII type.

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3D Segmentation for High-Resolution Image Datasets Using a Commercial Editing Tool in the IoT Environment

  • Kwon, Koojoo;Shin, Byeong-Seok
    • Journal of Information Processing Systems
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    • 제13권5호
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    • pp.1126-1134
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    • 2017
  • A variety of medical service applications in the field of the Internet of Things (IoT) are being studied. Segmentation is important to identify meaningful regions in images and is also required in 3D images. Previous methods have been based on gray value and shape. The Visible Korean dataset consists of serially sectioned high-resolution color images. Unlike computed tomography or magnetic resonance images, automatic segmentation of color images is difficult because detecting an object's boundaries in colored images is very difficult compared to grayscale images. Therefore, skilled anatomists usually segment color images manually or semi-automatically. We present an out-of-core 3D segmentation method for large-scale image datasets. Our method can segment significant regions in the coronal and sagittal planes, as well as the axial plane, to produce a 3D image. Our system verifies the result interactively with a multi-planar reconstruction view and a 3D view. Our system can be used to train unskilled anatomists and medical students. It is also possible for a skilled anatomist to segment an image remotely since it is difficult to transfer such large amounts of data.

Advanced Nanoscale Characterization of Cement Based Materials Using X-Ray Synchrotron Radiation: A Review

  • Chae, Sejung R.;Moon, Juhyuk;Yoon, Seyoon;Bae, Sungchul;Levitz, Pierre;Winarski, Robert;Monteiro, Paulo J.M.
    • International Journal of Concrete Structures and Materials
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    • 제7권2호
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    • pp.95-110
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    • 2013
  • We report various synchrotron radiation laboratory based techniques used to characterize cement based materials in nanometer scale. High resolution X-ray transmission imaging combined with a rotational axis allows for rendering of samples in three dimensions revealing volumetric details. Scanning transmission X-ray microscope combines high spatial resolution imaging with high spectral resolution of the incident beam to reveal X-ray absorption near edge structure variations in the material nanostructure. Microdiffraction scans the surface of a sample to map its high order reflection or crystallographic variations with a micron-sized incident beam. High pressure X-ray diffraction measures compressibility of pure phase materials. Unique results of studies using the above tools are discussed-a study of pores, connectivity, and morphology of a 2,000 year old concrete using nanotomography; detection of localized and varying silicate chain depolymerization in Al-substituted tobermorite, and quantification of monosulfate distribution in tricalcium aluminate hydration using scanning transmission X-ray microscopy; detection and mapping of hydration products in high volume fly ash paste using microdiffraction; and determination of mechanical properties of various AFm phases using high pressure X-ray diffraction.

z-버퍼를 이용한 효율적인 볼륨 데이터 항행기법 (An Efficient Navigation of Volume Dataset Using z-Buffer)

  • 김화진;신병석
    • 한국컴퓨터그래픽스학회논문지
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    • 제8권1호
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    • pp.29-35
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    • 2002
  • 가상 내시경에서는 고화질 영상을 빠른 속도로 만들어내는 것이 중요하지만 가상 카메라가 장기내벽과 충돌하지 않으면서 직관적이고 편리하게 카메라를 이동시킬 수 있는 항행 기법이 더 중요하다. 본 논문에서는 볼륨 광선 투사법을 이용하여 현재 프레임의 영상을 렌더링하는 과정에서 2차원 깊이 맵을 생성한 후에 이 값을 이용하여 다음 프레임에서의 카메라 위치와 방향을 결정하는 효율적인 항행 방법을 제안한다. 이 방법은 충돌 회피 조작을 하면서도 사용자가 임의로 카메라를 조작할 수 있도록 해주며 별도의 전처리 과정이나 자료구조가 필요 없이 카메라의 이동방향을 신속하게 계산할 수 있다. 이 방법을 가상 대장 내시경에 적용하여 효과적인 항행이 가능함을 보였다.

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기상 및 대기질 정보의 3차원 표출 최적화를 위한 시제품 개발 연구 (Prototype Development for Optimization Technique of 3D Visualization of Atmospheric Environmental Information)

  • 김건우;나하나;정우식
    • 한국환경과학회지
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    • 제28권11호
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    • pp.1047-1059
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    • 2019
  • To address the increase of weather hazards and the emergence of new types of such hazards, an optimization technique for three-dimensional (3D) representation of meteorological facts and atmospheric information was examined in this study as a novel method for weather analysis. The proposed system is termed as "meteorological and air quality information visualization engine" (MAIVE), and it can support several file formats and can implement high-resolution 3D terrain by employing a 30 m resolution digital elevation model. In this study, latest 3D representation techniques such as wind vector fields, contour maps, stream vector, stream line flow along the wind field and 3D volume rendering were applied. Implementation of the examples demonstrates that the results of numerical modeling are well reflected, and new representation techniques can facilitate the observation of meteorological factors and atmospheric information from different perspectives.

이미지 전처리를 이용한 전자현미경 볼륨 랜더링 시스템 (Volume Rendering System of Electron Microscopy using Image preprocessiong)

  • 정원구;정종만;이지영;이호;최상수;권희석;김윤중
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.100-103
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    • 2008
  • 한국기초과학지원연구원(KBSI, Korea Basic Science Institute)에서는 국내 유일의 초고전압투과전자현미경(HVEM, High Voltage Electron Microscopy)을 비롯하여 3대의 일반투과 전자현미경을 보유하고 있다. 전자현미경을 통하여 관찰된 이미지는 각 단계별로 tilting 되어 저장된 이미지로서 관찰자에게 보다 나은 관찰 환경의 구성을 위해 3D로의 reconstruction은 필수 과정이라고 할 수 있겠다. 이 과정 중 카메라 중심에서 벋어난 부분의 왜곡을 워핑기법을 통하여 최대한 감소시킨다. 이런 전처리 과정을 통하여 3D 구조물을 구성하게 되면 초기 이미지를 그대로 사용하는 것보다 한 단계 더 나은 결과물을 얻어낼 수 있다. 이미지 전처리를 이용한 전자현미경 볼륨 랜더링 시스템의 구축은 관찰자에게 보다 편리하며 빠른 실험 환경을 제공하여 줄 수 있고, 이해하기 쉽고 실제 모습에 가까운 형태의 실험 결과물을 접할 수 있게 된다.

CT검사에서 조영제의 혈관외유출에 의한 목 및 흉부 손상의 3차원 재구성 영상 (Extravasation Injury of Contrast Media in the Neck and Thorax During MDCT Scanning with 3D Image Reformation Findings)

  • 권대철;장근조;유병규;이종석
    • 대한방사선기술학회지:방사선기술과학
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    • 제30권3호
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    • pp.281-287
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    • 2007
  • 전산화단층촬영에서 조영제를 자동주입기로 주입하는 과정에서 발생하는 혈관외유출은 조직의 괴사 및 손상의 원인이 되고 있다. 대량의 혈관외유출은 구획증후군으로 발전하여 근막절개술을 시행하는 경우가 발생한다. 혈관외유출이 발생한 환자를 대상으로 혈관외유출 범위 및 부위 정도를 평가하기 위해 CT 검사에서 경정맥에 조영제을 주입하는 과정에서 혈관외유출이 발생한 환자를 대상으로 하였다. 조영제에 의한 혈관외유출 범위 및 손상을 확인하기 조영제 주입부위의 목 및 가슴의 부위를 MDCT를 이용하여 스캔하였다. 경정맥 주사부위의 혈관외유출부위를 MPR, MIP와 볼륨 렌더링의 3차원영상을 3D 프로그램을 이용하여 묘출하였다. 3차원 재구성 영상은 높은 해상력과 정확도를 제공하여 혈관외유출 범위 및 부위를 확인 하여, 환자의 예방의 필요성 및 사후 조치 및 적절한 치료와 수술 계획에 유용하게 이용될 것으로 기대된다.

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고속 내시경적 OFDI 시스템 개발과 이를 이용한 3차원 생체 혈관 내부 이미징 (Development of a High-Speed Endoscopic OCT System and Its Application to Three-Dimensional Intravascular Imaging in Vivo)

  • 조한샘;장선주;오왕열
    • 한국광학회지
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    • 제25권2호
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    • pp.67-71
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    • 2014
  • 혈관 내 OCT (optical coherence tomography) 는 혈관 벽 내부의 3차원적 미세구조를 영상화할 수 있어서 임상에서 각광을 받고 있다. 하지만 아직도 충분하지 못한 이미징 속도, 특히 내시경 프로브의 이미징 광 스캐닝 속도의 부족으로 혈관 길이 방향의 이미징 간격이 실제 시스템의 광학적 해상도보다 5배 이상 커서 혈관 종방향으로의 고해상도 이미징이 얻어지지 못하고 있는 상황이다. 본 논문에서는 초당 350장의 혈관 벽 단층 영상을 제공하는 고속 혈관 내 OCT 시스템을 기술한다. 본 시스템과 내시경 장치를 이용하여 47 mm 길이의 살아있는 토끼 대동맥을 3.7초만에 34 micron의 혈관 종방향 간격으로 얻는데 성공하였다. 34 micron의 종방향 간격은 실제 내시경의 그 방향 광학적 해상도와 비슷한 정도로서 3차원 모든 방향으로의 고해상도 이미징을 구현하였음을 보여준다. 얻어진 이미징 데이터의 3차원 영상 구현을 통해 혈관의 미세구조 및 이미징 전 삽입된 스텐트의 자세한 구조를 보였다.

에틸벤젠을 이용한 실리콘 산화물 음극재의 효과적인 카본 코팅 전략 (Effective problem mitigation strategy of lithium secondary battery silicon anode utilized liquid precursor)

  • 이상렬;박성수;채수종
    • 한국표면공학회지
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    • 제56권1호
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    • pp.62-68
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    • 2023
  • Silicon (Si) is considered as a promising substitute for the conventional graphite due to its high theoretical specific capacity (3579 mAh/g, Li15Si4) and proper working voltage (~0.3V vs Li+/Li). However, the large volume change of Si during (de)lithiation brings about severe degradation of battery performances, rendering it difficult to be applied in the practical battery directly. As a one feasible candidate of industrial Si anode, silicon monoxide (SiOx) demonstrates great electrochemical stability with its specialized strategy, downsized Si nanocrystallites surrounded by Li+ inactive buffer phase (Li2O and Li4SiO4). Nevertheless, SiOx inherently has the initial irreversible capacity and poor electrical conductivity. To overcome those issues, conformal carbon coating has been performed on SiOx utilizing ethylbenzene as the carbon precursor of chemical vapor deposition (CVD). Through various characterizations, it is confirmed that the carbon is homogeneously coated on the surface of SiOx. Accordingly, the carbon-coated SiOx from CVD using ethylbenzene demonstrates 73% of the first cycle efficiency and great cycle life (88.1% capacity retention at 50th cycle). This work provides a promising synthetic route of the uniform and scalable carbon coating on Si anode for high-energy density.

Comparing volumetric and biological aspects of 3D-printed interim restorations under various post-curing modes

  • Song, Gun;Son, Ji-Won;Jang, Ji-Hyun;Choi, Sung-Hyeon;Jang, Woo-Hyung;Lee, Bin-Na;Park, Chan
    • The Journal of Advanced Prosthodontics
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    • 제13권2호
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    • pp.71-78
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    • 2021
  • Purpose. This study aims to compare the volumetric change, degree of conversion (DOC), and cytotoxicity of 3D-printed restorations post-cured under three different conditions. Materials and Methods. 3D-printed interim restorations were post-cured under three different conditions and systems: 5 min, 30 min, and 24 h. Three-unit and six-unit fixed dental prostheses (n = 30 for each case) were printed; ten specimens from each group were post-cured and then scanned to compare their volumetric changes. Root-mean-squared (RMS) values of the data were acquired by superimposing the scanned files with original files. Thirty disk-shaped specimens were printed to evaluate the DOC ratio. Fourier transform infrared spectroscopy was used to compare the DOCs of 10 specimens from each group. Human gingival fibroblasts were used to measure the cell viability of every specimen (n = 7). The data from this experiment were employed for one-way analysis of variance and Tukey's post-hoc comparisons. Results. Differences between the three-unit restorations were statistically insignificant, regardless of the post-curing conditions. However, for the six-unit restorations, a high RMS value was acquired when the post-curing duration was 30 min. The average DOC was approximately 56 - 62%; the difference between each group was statistically insignificant. All the groups exhibited cell viability greater than 70%, rendering them clinically acceptable. Conclusion. The post-curing conditions influenced the volume when the length of the restoration was increased. However, this deviation was found to be clinically acceptable. Additionally, post-curing did not significantly influence the DOC and cytotoxicity of the restorations.