• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.802-805
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• 2002

In the three-dimensional domain image expressed with two-dimensional slice images, such as fMRI images and multi-slice CT images, we propose the three-dimensional domain automatic segmentation for the purpose of extracting region. In this paper, we segmented each domain from the fMRI images of the head of people and monkey. We used the neural network "Pulse-Coupled Neural Network" which is one of the models of visual cortex of the brain based on the knowledge from neurophysiology as the technique. By using this technique, we can segment the region without any learning. Then, we reported the result of division of each domain and extraction to the fMRI slice images of human's head using "three-dimensional Pulse-Coupled Neural Network" which is arranged and created the neuron in the shape of a three-dimensional lattice.

• Journal of the Optical Society of Korea
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• 제16권4호
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• pp.365-371
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• 2012

A three-dimensional integral-floating display with 360 degree horizontal viewing angle is proposed. A lens array integrates two-dimensional elemental images projected by a digital micro-mirror device, reconstructing three-dimensional images. The three-dimensional images are then relayed to a mirror via double floating lenses. The mirror rotates in synchronization with the digital micro-mirror device to direct the relayed three-dimensional images to corresponding horizontal directions. By combining integral imaging and the rotating mirror scheme, the proposed method displays full-parallax three-dimensional images with 360 degree horizontal viewing angle.

• Applied Microscopy
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• 제36권3호
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• pp.217-226
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• 2006

발달중인 Sedum 및 Salsola의 엽육조직을 chemical fixation과 high pressure freezing (HPF) 등으로 고정한 후, 초박 및 후박절편으로 제작 carbon coating하여 TEM 및 UHVEM으로 연속절편에 의한 2-D영상과 tilt image data를 수집하였다. 이후 초미세 구조들에 대하여 tilting 및 tomography 기법, 그리고 디지털화한 image의 3-D 입체구조 재구현에 필수적인 IMOD 프로_그램을 적용한 image 처리과정을 거쳐 UHVEM data에서 색소체내 초미세구조의 정보를 추출하여 세포수준에서의 3-D image를 분석하였다. 색소체 기질에서 녹말입자 및 틸라코이드에 인접하여 형성되는 CAM및 $C_4$ 식물 색소체 결정체들은 어떤 막으로도 둘러싸이지 않는 구조로서, Sedum rotundifolium 색소체내 결정체는 수 ${\mu}m$에 이르는 커다란 크기로 형성된다. 결정체 내에는 약 20nm격자거리로 이루어진 기원을 알 수 없는 수백-수천 개의 미세소관성 요소들이 평행 또는 격자상태로 정교한 구조를 이루며, 티라코이드 및 녹말입자와 인접하여 발달하였다. $C_4$ 광합성 수행 Salsola komarovii의 경우, 결정체는 엽육세포 색소체에서만 발달하며 결정체 구성 기본요소들이 비교적 규칙적인 격자거리를 이루며 수십 개 배열하는 구조를 형성하였다. 특히, tilted image및 3-D 입체구조 연구에서 결정체 형성에는 이들과 인접하여 발달하는 틸라코이드막이 관여함을 알아 낼 수 있었다. 이는 엽육세포 색소체에는 결정체들이 식물이 수행하는 광합성 유형에 따라 각기 다른 구성요소로 형성되어 Sedum의 경우와 같이 발달 중인 엽육조직에서 분화하거나 Salsola에서와 같이 세포 유형에 따라 상이하게 발달하는 것으로 추정되었다.

• Fibers and Polymers
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• 제7권1호
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• pp.57-61
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• 2006

A study has been made on the quantification and evaluation of fabric pilling using two-dimensional and three-dimensional hybrid imaging methods. Two-dimensional imaging method was good for some samples while three-dimensional measurement method for others, according to the properties of their base fabric. Various image processing techniques as well as three-dimensional data processing algorithms were applied for the extraction of pills from measured data and a series of shape parameters have been defined for the objective evaluation of fabric pilling. An evaluation criterion that is compatible with the conventional evaluation method has been proposed by applying the new evaluation method to the current photographic standards.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.155-162
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• 2019

To reduce the secondary damage caused by leakage accidents in plant piping systems, a constant surveillance system is necessary. To ensure leaks are promptly addressed, the surveillance system should be able to detect not only the leak itself, but also the location of the leak. Recently, research to develop new methods has been conducted using cameras to detect leakage and to estimate the location of leakage. However, existing methods solely estimate whether a leak exists or not, or only provide two-dimensional coordinates of the leakage location. In this paper, a method using multiple cameras to detect leakage and estimate the three-dimensional coordinates of the leakage location is presented. Leakage is detected by each camera using MADI(Moving Average Differential Image) and histogram analysis. The two-dimensional leakage location is estimated using the detected leakage area. The three-dimensional leakage location is subsequently estimated based on the two-dimensional leakage location. To achieve this, the coordinates (x, z) for the leakage are calculated for a horizontal section (XZ plane) in the monitoring area. Then, the y-coordinate of leakage is calculated using a vertical section from each camera. The method proposed in this paper could accurately estimate the three-dimensional location of a leak using multiple cameras.

• 국토계획
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• 제54권2호
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• pp.93-108
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• 2019

This study examines the relationship between three-dimensional urban built environment and urban surface temperature using LANDSAT 8 satellite image data in Seoul city. The image was divided into 600m×600m grid units as an unit of analysis. Due to the high level of spatial dependency in surface temperature, this study uses spatial statistics to take into account spatial auto-correlation. The spatial error model shows the best goodness of fit. The analysis results show that the three-dimensional built environment and transport environment as well as natural environment have statistically significant associations with surface temperature. First, natural environment variables such as green space, streams and river, and average elevation show statistically significant negative association with surface temperature. Second, the building area shows a positive association with surface temperature. In addition, while sky view factor (SVF) has a positive association with surface temperature, surface roughness (SR) shows a negative association with it. Third, transportation related variables such as road density, railway density, and traffic volume show positive associations with surface temperature. Moreover, this study finds that SVF and SR have different effects on surface temperature in regard to the levels of total floor areas in built environment. The results indicate that interactions between floor area ratio (FAR) and three-dimensional built environmental variables such as SVF and SR should be considered to reduce urban surface temperature.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2605-2608
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• 2003

This paper presents design and implementation methods of the real-time three dimensional tracking system of the gazing point. The proposed method is based on three dimensional data processing of eye images in the 3D world coordinates. The system hardware consists of two conventional CCD cameras for acquisition of stereoscopic image and computer for processing. And in this paper, the advantages of the proposed algorithm and test results ate described.

• 대한의용생체공학회:의공학회지
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• 제10권2호
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• pp.157-164
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• 1989

Three-dimensional imaging and manipulation of CT data are becoming increasingly important for deterRing the complex structure and pathologies. Octree which is a hierarchical data model is used to reconstruct three- dimensional objects from CT scans. Orthogonal cross sections are displayed by traverse the octree partially. Arbitrary oblique planes are derived by intersecting the square region of plane and cubic volume of octal node. Thia method enables the display of multi-structured complex organ ann the realization by personal computer.

• Fibers and Polymers
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• 제2권1호
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• pp.163-172
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• 2001

To determine three-dimensional fiber orientation states in injection-molded short fiber composites a CLSM (Confocal Laser Scanning Microscope) is used. Since the CLSM optically sections the composites, more than two cross-sections either on or below the surface of the composite can be obtained. Three dimensional fiber orientation states can be determined with geometric parameters of fibers on two parallel cross-sections. For experiment, carbon fiber reinforced polystyrene is examined by the CLSM. Geometric parameters of fibers are measured by image analysis. In order to compactly describe fiber orientation states, orientation tensors are used. Orientation tensors are determined at different positions of the prepared specimen. Three dimensional orientation states are obtained without the difficulty in determining the out-of-plane angles by utilizing images on two parallel planes acquired by the CLSM. Orientation states are different at different positions and show the shell-core structure along the thickness of the specimen.

• 대한의용생체공학회:의공학회지
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• 제17권3호
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• pp.305-312
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• 1996

A new three dimensional fractal coding is proposed with a perceptually enhanced matching. Since most of medical images (e.g. computed tomoyaphy or magnetic resonance images) have three dimensional characters, searching regions are extended to adjacent slices. For a perceptually enhanced matching, a high frequency boost filter is used for pre-filtering images to be encoded, and a least mean square error matching is applied to the edge enhanced Images rather than the original images. From simulation with magnetic resonance images($255\times255$, 8bits/pixel), reconstructed images by the proposed compression algorithm show much improved subjective image quality with higher peak signnal-to-noise ratio compared to those by existing fractal coding algorithms at compression ratios of about 10.