• Title/Summary/Keyword: Overlapped projection

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High resolution 3D display using time-multiplexed overlapped projection

  • Baasantseren, Ganbat;Park, Jae-Hyeung;Kim, Nam
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1338-1340
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    • 2009
  • High resolution three-dimensional integral imaging display is proposed. Each time-multiplexed image is projected with different incident angle on same array of elemental lenses. Those images are collected at different positions in focal plane of lens array, and thus the number of the point light sources increases and their spacing decreases. Therefore, proposed method can create high resolution 3D images.

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A Survey on Quality of Radiographs in Frontal Projection of the Chest (흉부(胸部) 정면(正面)X선사진(線寫眞)의 화질(畵質)에 관한 검사(檢討))

  • Choi, Jong-Hak;Jeon, Man-Jin;Lee, Chang-Yup
    • Journal of radiological science and technology
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    • v.8 no.2
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    • pp.11-14
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    • 1985
  • The author came to analize and get the following problems after researched radiographic quality in order to find out the necessary factors to improve in radiographs of frontal projection of the chest selected at random of the adult patients (1545 male, 1520 female) who had been examined in 4 departments of radiology of the general hospitals in Seoul and Kyungki area. 1. Problems of x-ray film or of radiographic cassette appeared in 2.97% radiographs on account of selection of the film size (except costophrenic sinus) (1.79%), poor screen-film contact (0.85%), light leakage of cassette (0,33%). 2. Problems of patients' positioning or breathing appeared in 16.57% radiographs of all because of overlapping of lung apex and clavicle (6.98%), overlapping of scapula and lung field (5.87%), asymmetrical projection of clavicles (1.76%), errors in positioning and breathing of the patient (1.96%). 3. Problems of x-ray exposure factors or film processing appeared in 22.25% radiographs because of over-density (2.64%), under-density (3.95%), fog (0.59%), demonstration density under clavicles or lung marking unsharply (3.82%), not clear of lung marking from breast region (0.94%), not clear the lung marking from the part overlapped of heart and lungs (3.92%), not clear the lung marking from the part overlapped of liver and lung (6.49%).

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-Axis NC Milling Simulation (3축 NC 기계 가공 시뮬레이션)

  • 안정호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1993.10a
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    • pp.423-427
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    • 1993
  • An efficient 3-axis NC milling simulator is presented. The geometric simulation of milling is based on z-map structure and voxels. For the graphic simulation,dimetric projection is adopted. As a result, two faces of a voxel are exposed and they are overlapped. Visible faces are determined by using z-butter method. The simulation system is developed in IBM-PC compatible with satisfactory result.

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Character Segmentation in Chinese Handwritten Text Based on Gap and Character Construction Estimation

  • Zhang, Cheng Dong;Lee, Guee-Sang
    • International Journal of Contents
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    • v.8 no.1
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    • pp.39-46
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    • 2012
  • Character segmentation is a preprocessing step in many offline handwriting recognition systems. In this paper, Chinese characters are categorized into seven different structures. In each structure, the character size with the range of variations is estimated considering typical handwritten samples. The component removal and merge criteria are presented to remove punctuation symbols or to merge small components which are part of a character. Finally, the criteria for segmenting the adjacent characters concerning each other or overlapped are proposed.

The Character Area Extraction and the Character Segmentation on the Color Document (칼라 문서에서 문자 영역 추출믹 문자분리)

  • 김의정
    • Journal of the Korean Institute of Intelligent Systems
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    • v.9 no.4
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    • pp.444-450
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    • 1999
  • This paper deals with several methods: the clustering method that uses k-means algorithm to abstract the area of characters on the image document and the distance function that suits for the HIS coordinate system to cluster the image. For the prepossessing step to recognize this, or the method of characters segmentate, the algorithm to abstract a discrete character is also proposed, using the linking picture element. This algorithm provides the feature that separates any character such as the touching or overlapped character. The methods of projecting and tracking the edge have so far been used to segment them. However, with the new method proposed here, the picture element extracts a discrete character with only one-time projection after abstracting the character string. it is possible to pull out it. dividing the area into the character and the rest (non-character). This has great significance in terms of processing color documents, not the simple binary image, and already received verification that it is more advanced than the previous document processing system.

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A Study on the Extraction of an Individual Character and Chinese Characters Recognition on the Off-line Documents (오프라인 문서에서 개별 문자 추출과 한자 인식에 관한 연구)

  • Kim, Ui-Jeong;Kim, Tae-Gyun
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.5
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    • pp.1277-1288
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    • 1997
  • In this paper,the extraciton method for individual and the recognition method for the printed dociments are discussed. In preprocessing is a technique to extract characters that are difficult to manage such as touching characters or overlapped chracters.Genrally in the existing segmentation methods,projection and edge detection are applied.However,in this paper an indvidual character is extracted by using connected pixel with one projection after the string extraction The maximum Blok Methld(MBM)is used for the recognition.The MBM is a method to enlarge the block to the last point the pixel that was found during projection. The maximum blocks are skeletonxied after the division into straight line block and oblique line block.Especially,in the recognition of chinese chracters compared to the existing method it showed improved recognition rate.

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Post-processing Technique based on POCS for visual Enhancement (POCS를 이용한 효과적인 블록 현상 제거 기법)

  • Kim, Yoon;Jung, Jae-Han;Kim, Jae-Won;Ko, Sung-Jea
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.755-758
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    • 2001
  • In this paper. Ive propose a postprocessing technique based on the theory of projection on convex sets(POCS) to reduce the blocking artifacts in HDTV decoded images. In BDCT of HDTV. the image is divided into a grid of non-overlapped 8 ${\times}$ 8 blocks. and then each block is coded separately. A block which is located one pixel apart from the grid of BDCT will include the boundary of the original 8 ${\times}$ 8 block. If the blocking artifact is Introduced alone the block boundary. this block will have different frequency characteristic from that of the original block. Thus, a comparison of frequency characteristics of these two overlapping blocks can detect the undesired high-frequency components mainly caused by the blocking artifact. By eliminating these undesired high-frequency components adaptively, robust smoothing projection operator can be obtained. Simulation results with real image sequences indicate that the proposed method performs better than conventional algorithms.

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Studies of the Central Neural Pathways to the Hapgok(LI4) and Large Intestine (합곡과 대장의 중추신경로와의 연계성에 관한 연구)

  • Lee, Chang-Hyun;Jeong, Han-Sol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.2
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    • pp.217-226
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    • 2011
  • The aim of this study is to identify central neural pathway of neurons following the projection to the large intestine and Hapgok(LI4) which is Won acupoint of the large intestine meridian of hand-yangmyeong. In this experiment, Bartha's strain of pseudorabies virus was used to trace central localization of neurons related with large intestine and acupoint(LI4) which has been known to be able to regulate intestinal function. The animals were divided into 3 groups: group 1, injected into the large intestine; group 2, injected into the acupoint(LI4); group 3, injected into the acupoint(LI4) after severing the radial, ulnar, median nerve. After four days survival of rats, PRV labeled neurons were identified in the spinal cord and brain by immunohistochemical method. First-order PRV labeled neurons following the projection to large intestine, acupoint(LI4) and acupoint(LI4) after cutting nerve were found in the cervical, thoracic, lumbar and sacral spinal cord. Commonly labeled neurons were labeled in the lumbosacral spinal cord and thoracic spinal cord. They were found in lamina V- X, intermediomedial nucleus and dorsal column area. The area of sensory neurons projecting was L5-S2 spinal ganglia and T12-L1 spinal ganglia, respectively. In the brainstem, the neurons were labeled most evidently and consistently in the nucleus tractus solitarius, area postrema, dorsal motor nucleus of vagus nerve, reticular nucleus, raphe nuclei(obscurus, magnus and pallidus), C3 adrenalin cells, parapyramidal area(lateral paragigantocellular nucleus), locus coeruleus, subcoeruleus nucleus, A5 cell group, periaqueductal gray matter. In the diencephalon, PRV labeled neurons were marked mostly in the arcuate nucleus and median eminence. These results suggest that overlapped CNS locations are related with autonomic nuclei which regulate the functions of large intestine-related organs and it was revealed by tracing PRV labeled neurons projecting large intestine and related acupoint(LI4).

Facial Image Segmentation using Wavelet Transform (웨이브렛 변환을 적용한 얼굴영상분할)

  • 김장원;박현숙;김창석
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.45-52
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    • 2000
  • In this study, we propose the image segmentation algorithm for facial region segmentation. The proposed algorithm separates the mean image of low frequency band from the differential image of high frequency band in order to make a boundary using HWT, and then we reduce the isolation pixels, projection pixels, and overlapped boundary pixels from the low frequency band. Also the boundaries are detected and simplified by the proposed boundary detection algorithm, which are cleared on the thinning process of 1 pixel unit. After extracting facial image boundary by using the proposed algorithm, we make the mask and segment facial image through matching original image. In the result of facial region segmentation experiment by using the proposed algorithm, the successive facial segmentation have 95.88% segmentation value.

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Local Similarity based Discriminant Analysis for Face Recognition

  • Xiang, Xinguang;Liu, Fan;Bi, Ye;Wang, Yanfang;Tang, Jinhui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.11
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    • pp.4502-4518
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    • 2015
  • Fisher linear discriminant analysis (LDA) is one of the most popular projection techniques for feature extraction and has been widely applied in face recognition. However, it cannot be used when encountering the single sample per person problem (SSPP) because the intra-class variations cannot be evaluated. In this paper, we propose a novel method called local similarity based linear discriminant analysis (LS_LDA) to solve this problem. Motivated by the "divide-conquer" strategy, we first divide the face into local blocks, and classify each local block, and then integrate all the classification results to make final decision. To make LDA feasible for SSPP problem, we further divide each block into overlapped patches and assume that these patches are from the same class. To improve the robustness of LS_LDA to outliers, we further propose local similarity based median discriminant analysis (LS_MDA), which uses class median vector to estimate the class population mean in LDA modeling. Experimental results on three popular databases show that our methods not only generalize well SSPP problem but also have strong robustness to expression, illumination, occlusion and time variation.