• Title/Summary/Keyword: CT data

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Liver Tumor Detection Using Texture PCA of CT Images (CT영상의 텍스처 주성분 분석을 이용한 간종양 검출)

  • Sur, Hyung-Soo;Chong, Min-Young;Lee, Chil-Woo
    • The KIPS Transactions:PartB
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    • v.13B no.6 s.109
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    • pp.601-606
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    • 2006
  • The image data amount that used in medical institution with great development of medical technology is increasing rapidly. Therefore, people need automation method that use image processing description than macrography of doctors for analysis many medical image. In this paper. we propose that acquire texture information to using GLCM about liver area of abdomen CT image, and automatically detects liver tumor using PCA from this data. Method by one feature as intensity of existent liver humor detection was most but we changed into 4 principal component accumulation images using GLCM's texture information 8 feature. Experiment result, 4 principal component accumulation image's variance percentage is 89.9%. It was seen this compare with liver tumor detecting that use only intensity about 92%. This means that can detect liver tumor even if reduce from dimension of image data to 4 dimensions that is the half in 8 dimensions.

Development of a Small Animal CT using a Linear Detector Array and Small-Scale Slip Rings

  • An Ung Hwan;Chun In Kon;Lee Sang Chul;Cho Min Hyoung;Lee Soo Yeol
    • Journal of Biomedical Engineering Research
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    • v.26 no.1
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    • pp.43-47
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    • 2005
  • We have developed a small bore x-ray CT for small animal imaging with a linear x-ray detector array and small-scale slip rings. The linear x-ray detector array consists of 1024 elements of 400□m×400□m with a gadolinium oxysulfide (GOS) scintillator on top of them. To avoid use of expensive large diameter slip rings for projection data transmission from the X­ray detector to the image reconstruction system, we used the wireless LAN technology. The projection data are temporally stored in the data acquisition system residing on the rotating gantry during the scan and they are transmitted to the image reconstruction system after the scan. With the wireless LAN technology, we only needed to use small-scale slip rings to deliver the AC electric power to the X-ray generator and the power supply on the rotating gantry. The performances of the small animal CT system, such as SNR, contrast, and spatial resolution, have been evaluated through experiments using various phantoms. It has been experimentally found that the SNR is almost linearly proportional to the tube current and tube voltage, and the minimum resolvable contrast is less than 30 CT numbers at 40kVp/3.0㎃. The spatial resolution of the small animal CT system has been found to be about 0.9Ip/㎜. Postmortem images of a piglet is also presented.

Quantitative Evaluation of CT Artifact Elimination with various Cut-off Frequency of Hann Filter (Hann 필터의 Cut-off 주파수 변화에 따른 CT 영상의 Artifact 제거효과에 대한 정량적 평가)

  • Kang, Bo-Sun
    • Journal of the Korean Society of Radiology
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    • v.2 no.3
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    • pp.5-9
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    • 2008
  • In the computerized tomography(CT), various filters are using in the reconstruction algorithm to reduce or eliminate the artifacts which are intrinsically induced by the imperfection of mathematical methods for reconstruction, lack of real informations about anatomic structures in the projection image, errors in data acquisition and so on. Hann filter was used to evaluate the filter effects on the elimination of reconstruction artifact in the CT image. The quantitative study was done by changing cut-off frequency of Hann filter from 0.1 to 0.9 with frequency increasement by 0.2. NPS analysis was fulfilled for the quantitative evaluation of filter effect.

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Cholera Toxin Disrupts Oral Tolerance via NF-κB-mediated Downregulation of Indoleamine 2,3-dioxygenase Expression

  • Kim, Kyoung-Jin;Im, Suhn-Young
    • Biomedical Science Letters
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    • v.23 no.3
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    • pp.175-184
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    • 2017
  • Cholera toxin (CT) is an ADP-ribosylating bacterial exotoxin that has been used as an adjuvant in animal studies of oral immunization. The mechanisms of mucosal immunogenicity and adjuvanticity of CT remain to be established. In this study, we investigated the role of indoleamine 2,3-dioxygenase (IDO), which participates in the induction of immune tolerance, in CT-mediated breakdown of oral tolerance. When IDO-deficient ($IDO^{-/-}$) mice and their littermates were given oral ovalbumin, significant changes in antibody responses, footpad swelling and $CD4^+$ T cell proliferation were not observed in $IDO^{-/-}$ mice. Feeding of CT decreased IDO expression in mesenteric lymph nodes (MLN) and Peyer's patch (PP). CT-induced downregulation of IDO expression was reversed by inhibitors of nuclear factor-kappa B (NF-${\kappa}B$), pyrrolidine dithiocarbamate and p50 small interfering RNA. IDO expression was downregulated by the NF-${\kappa}B$ inducers lipopolysaccharide and tumor necrosis factor-${\alpha}$. CT dampened IDO activity and mRNA expression in dendritic cells from MLN and PP. These data indicate that CT disrupts oral tolerance by activating NF-${\kappa}B$, which in turn downregulates IDO expression. This study betters the understanding of the molecular mechanism underlying CT-mediated abrogation of oral tolerance.

Analysis of Scratch code for Student Assessment about Computational Thinking Capability (Computational Thinking 역량에 대한 학습자 평가를 위한 스크래치 코드 분석)

  • Kim, Soohwan
    • The Journal of Korean Association of Computer Education
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    • v.18 no.5
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    • pp.25-34
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    • 2015
  • The purpose of this research is to suggest the method of code analysis for evaluating learners' projects in computational thinking(CT) education. Recently, block programming tools are applied to K-12 SW education, this study considered the assessment method for evaluating students' levels and learning about CT concepts through analyzing codes of the Scratch projects that students created. As a result from the analysis of 45 projects of novices, it showed the bad coding patterns of novices and verified that it is possible to evaluate students' learning about CT concepts through the analysis of their codes. The higher learner's level, the greater scores of logical thinking, synchronization, flow control, and data representation. This result is able to apply to student assessment of CT concepts in K-12 SW education.

Structure of CT26 in the C-terminal of Amyloid Precursor Protein Studied by NMR Spectroscopy

  • Kang, Dong-Il;Baek, Dong-Ha;Shin, Song-Yub;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • v.26 no.8
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    • pp.1225-1228
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    • 2005
  • C-terminal fragments of APP (APP-CTs), that contain A$\beta$ sequence, are found in neurotic plaques, neurofibrillary tangles and the cytosol of lymphoblastoid cells obtained from AD patients. CT26, Thr639-Asp664 (TVIVITLVMLKKKQYTSIHH GVVEVD) includes not only the transmembrane domain but also the cytoplasmic domain of APP. This sequence is produced from cleavage of APP by caspase and $\gamma$-secretase. In this study, the solution structure of CT26 was investigated using NMR spectroscopy and circular dichroism (CD) spectropolarimeter in various membrane-mimicking environments. According to CD spectra and the tertiary structure of CT26 determined in TFE-containing aqueous solution, CT26 has an α-helical structure from $Val^{2}\;to\;Lys^{11}$ in TFE-containing aqueous solution. However, according to CD data, CT26 adopts a $\beta$-sheet structure in the SDS micelles and DPC micelles. This result implies that CT26 may have a conformational transition between $\alpha$-helix and $\beta$-sheet structure. This study may provide an insight into the conformational basis of the pathological activity of the C-terminal fragments of APP in the model membrane.

Quantitative analysis of three dimensional volumetric images in Chest CT (흉부 CT 검사에서 3차원 체적 영상의 정량적 분석)

  • Jang, Hyun-Cheol;Cho, Jae-Hwan;Park, Cheol-Soo
    • Journal of the Korean Society of Radiology
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    • v.5 no.5
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    • pp.255-260
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    • 2011
  • We wanted to evaluate the usefulness of three-dimensional reconstructive images using computed tomography for rib fracture patients. The reconstruction used in clinical multi planar reformation(MPR), volume rendering technique(VRT), and image data using quantitative methods and qualitative methods were compared. Much more, the artifact shadow was minimized to reconstruct with 3D volumetric image by using an law data in the analysis of the reconstructive image and chest CT scan of the evaluation result fractures of the thoracic patient. And we could know that the fractures of the thoracic determination and three dimension volume image reconstruction time were reduced.

A Compensated Current Acqaisition Device for CT Saturation (왜곡 전류 보상형 전류 취득 장치)

  • Ryu, Ki-Chan;Gang, Soo-Young;Kang, Sang-Hee
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.96-98
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    • 2005
  • In this paper, an algorithm to compensate the distorted signals due to Current Transformer(CT) saturation is suggested, First, DWT which can be easily realized by filter banks in real-time applications is used to detect a start point and an end point of the saturation. Secondly, For enough Datas those need to use the least-square curve fitting method, the distorted current signal is compensated by the AR(autoregressive) model using the data during the previous healthy section until pick point of Saturation. Thirdly, the least-square curve fitting method is used to restore the distorted section of the secondary current. Finaly, this algorithm had a Hadware test using DSP board(TMS320C32) with Doble test device. DWT has superior detection accuracy and the proposed compensation algorithm which shows very stable features under various levels of remanent flux in the CT core is also satisfactory. And this algorithm is more correct than a previous algorithm which is only using the LSQ fitting method. Also it can be used as a MU involving the compensation function that acquires the second data from CT and PT.

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A Study on 3D CT Image Segmentation and Registration of Mandibular First Premolar (하학 제 1 소구치의 3 차원 CT 영상 분할 및 정합 연구)

  • Jin K.C.;Chun K.J.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.175-176
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    • 2006
  • The aim of the 3D medical imaging is to facilitate the creation of clinically usable image-based algorithm. Clinically usable imaging algorithm for image analysis requires a high degree of interaction to verify and correct results from registration algorithms, such as the Insight Toolkit (ITK) and the Visualization Toolkit (VTK) which are the class libraries. ITK provides segmentation algorithms and VTK has powerful 3D visualization. However, to apply those libraries to the medical images such as Computerized Tomography (CT), the algorithm based on the interactive construction and modification of data objects are necessary. In this paper we showed the 3D registration about mandibular premolar of human teeth acquired by micro-CT scanner. Also, we used the ITK to find the contour of pulp layer of premolar, furthermore, the 3D imaging was visualized with VTK designed to create one kind of view on the data of 3D visualization. Finally, we evaluated that the volume model of pulp layer would be useful for the tooth morphology in dental medicine.

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Feasibility Study of CNN-based Super-Resolution Algorithm Applied to Low-Resolution CT Images

  • Doo Bin KIM;Mi Jo LEE;Joo Wan HONG
    • Korean Journal of Artificial Intelligence
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    • v.12 no.1
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    • pp.1-6
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    • 2024
  • Recently, various techniques are being applied through the development of medical AI, and research has been conducted on the application of super-resolution AI models. In this study, evaluate the results of the application of the super-resolution AI model to brain CT as the basic data for future research. Acquiring CT images of the brain, algorithm for brain and bone windowing setting, and the resolution was downscaled to 5 types resolution image based on the original resolution image, and then upscaled to resolution to create an LR image and used for network input with the original imaging. The SRCNN model was applied to each of these images and analyzed using PSNR, SSIM, Loss. As a result of quantitative index analysis, the results were the best at 256×256, the brain and bone window setting PSNR were the same at 33.72, 35.2, and SSIM at 0.98 respectively, and the loss was 0.0004 and 0.0003, respectively, showing relatively excellent performance in the bone window setting CT image. The possibility of future studies aimed image quality and exposure dose is confirmed, and additional studies that need to be verified are also presented, which can be used as basic data for the above studies.