• Title/Summary/Keyword: second projection method

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Three-Dimensional Digital Subtraction Angiography (디지털 혈관 조영술 영상의 3차원적 해석)

  • 이승지;김희찬
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.20 no.1
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    • pp.63-71
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    • 1983
  • A dye-edge tracking algorithm was used to determine the corresponding points in the two images(anterior-posterior and lateral) of the digital subtraction biplane angiography. This correspondence was used to reconstruct three dimensional images of cerebral artery in a dog experiment. The method was tested by comparing the measured image of oblique view with the computed reconstructed image. For the present study, we have developed three new algorithms. The first algorithm is to determine the corresponding dye-edge points using the fact the dye density at the moving edge avows the same changing pattern in the two projection views. This moving pattern of dye-edge density is computed using a matching method of cross-correlation for the two sequential frames' dye density. The second algorithm is for simplified perspective transformation, and the third one is to identify the specific corresponding points on the small vessels. The present method can be applied to compute the blood velocity using the dye-edge displacement and the three- dimensional distance data.

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A Method for the Increasing Efficiency of the Watershed Based Image Segmentation using Haar Wavelet Transform (Haar 웨이블릿 변환을 사용한 Watershed 기반 영상 분할의 효율성 증대를 위한 기법)

  • 김종배;김항준
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.2
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    • pp.1-10
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    • 2003
  • This paper presents an efficient method for image segmentation based on a multiresolution application of a wavelet transform and watershed segmentation algorithm. The procedure toward complete segmentation consists of four steps: pyramid representation, image segmentation, region merging and region projection. First, pyramid representation creates multiresolution images using a wavelet transform. Second, image segmentation segments the lowest-resolution image of the pyramid using a watershed segmentation algorithm. Third, region merging merges the segmented regions using the third-order moment values of the wavelet coefficients. Finally, the segmented low-resolution image with label is projected into a full-resolution image (original image) by inverse wavelet transform. Experimental results of the presented method can be applied to the segmentation of noise or degraded images as well as reduce over-segmentation.

Evaluating LIMU System Quality with Interval Evidence and Input Uncertainty

  • Xiangyi Zhou;Zhijie Zhou;Xiaoxia Han;Zhichao Ming;Yanshan Bian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.11
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    • pp.2945-2965
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    • 2023
  • The laser inertial measurement unit is a precision device widely used in rocket navigation system and other equipment, and its quality is directly related to navigation accuracy. In the quality evaluation of laser inertial measurement unit, there is inevitably uncertainty in the index input information. First, the input numerical information is in interval form. Second, the index input grade and the quality evaluation result grade are given according to different national standards. So, it is a key step to transform the interval information input by the index into the data form consistent with the evaluation result grade. In the case of uncertain input, this paper puts forward a method based on probability distribution to solve the problem of asymmetry between the reference grade given by the index and the evaluation result grade when evaluating the quality of laser inertial measurement unit. By mapping the numerical relationship between the designated reference level and the evaluation reference level of the index information under different distributions, the index evidence symmetrical with the evaluation reference level is given. After the uncertain input information is transformed into evidence of interval degree distribution by this method, the information fusion of interval degree distribution evidence is carried out by interval evidential reasoning algorithm, and the evaluation result is obtained by projection covariance matrix adaptive evolution strategy optimization. Taking a five-meter redundant laser inertial measurement unit as an example, the applicability and effectiveness of this method are verified.

Detection of the co-planar feature points in the three dimensional space (3차원 공간에서 동일 평면 상에 존재하는 특징점 검출 기법)

  • Seok-Han Lee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.6
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    • pp.499-508
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    • 2023
  • In this paper, we propose a technique to estimate the coordinates of feature points existing on a 2D planar object in the three dimensional space. The proposed method detects multiple 3D features from the image, and excludes those which are not located on the plane. The proposed technique estimates the planar homography between the planar object in the 3D space and the camera image plane, and computes back-projection error of each feature point on the planar object. Then any feature points which have large error is considered as off-plane points and are excluded from the feature estimation phase. The proposed method is archived on the basis of the planar homography without any additional sensors or optimization algorithms. In the expretiments, it was confirmed that the speed of the proposed method is more than 40 frames per second. In addition, compared to the RGB-D camera, there was no significant difference in processing speed, and it was verified that the frame rate was unaffected even in the situation that the number of detected feature points continuously increased.

Effectiveness of "Village Image Construction Tool Kit" in the Residents Workshop of a Housing Improvement Area (주거지 정비지역 주민 워크샵을 통한 마을이미지 맵 제작도구의 효용성 연구)

  • Lee, Yeun-Sook;Kim, Ju-Suck;Jung, Eun-Jung
    • Journal of the Korean housing association
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    • v.21 no.1
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    • pp.67-77
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    • 2010
  • Citizen participation in local redevelopment has recently been regarded as essential, since progress in democracy and diversified public interests have contributed to more importance being placed on citizen participation in the implementation of public policies. While the importance of resident participation has been increasingly emphasized in principle, in reality more effort is still required in its application. We need to develop practical strategies of collecting community opinion in order to reflect it in public policy, if we are to achieve a resident and citizen-centered society. The purpose of this study is to develop an image map construction tool that can be applied to the "Maul-Mandulgi" projects as a visualized method to facilitate the exchange of opinions and work toward agreements. The tool is intended to assist public discussion by visualizing policies and plans and reducing the possibility of misunderstanding, so that residents can properly respond to the plans. Second, this study will verify the effectiveness of the tool in the application to local community workshops. The main research method is participant observation method and field study. Major findings are as follows, First, every resident who had participated in previous workshops gathered together, used the tool and represented their opinions unusually more than once. Each resident tried to make sure that other participants appropriately understood his or her opinion. The workshop finished when all participants agreed and produced a consensus. The workshop took much less time, which is in stark contrast to previous workshops in which it took significantly more time to collect opinions. Second, it proved that residents in the redevelopment area can strike a broad agreement by themselves on a method and direction for residential improvement. In previous workshops, conflicts between residents developed over the choice between the two methods, of local improvement and total demolition prior to multi-housing construction. In this study, opinions of residents were not limited to the two methods by finding a winwin solution. Third, the use of the tool kit for image map became efficient for inactive residents to develop their own opinions in regard to the direction and orientations of the residential improvement process. In addition, for those who have either no or a slight understanding of the residential improvement projects, the tool can provide access to information and knowledge. This study concludes that the developed tool for imaging of the redevelopment projection like a design game, rather than using forms of text and speech, can be a useful tool in collecting opinions and forming an agreed opinion for forthcoming residential improvement plans.

Word Segmentation in Handwritten Korean Text Lines based on GAP Clustering (GAP 군집화에 기반한 필기 한글 단어 분리)

  • Jeong, Seon-Hwa;Kim, Soo-Hyung
    • Journal of KIISE:Software and Applications
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    • v.27 no.6
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    • pp.660-667
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    • 2000
  • In this paper, a word segmentation method for handwritten Korean text line images is proposed. The method uses gap information to segment words in line images, where the gap is defined as a white run obtained after vertical projection of line images. Each gap is assigned to one of inter-word gap and inter-character gap based on gap distance. We take up three distance measures which have been proposed for the word segmentation of handwritten English text line images. Then we test three clustering techniques to detect the best combination of gap metrics and classification techniques for Korean text line images. The experiment has been done with 305 text line images extracted manually from live mail pieces. The experimental result demonstrates the superiority of BB(Bounding Box) distance measure and sequential clustering approach, in which the cumulative word segmentation accuracy up to the third hypothesis is 88.52%. Given a line image, the processing time is about 0.05 second.

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Evaluation of Firmness and Sweetness Index of Tomatoes using Hyperspectral Imaging

  • Rahman, Anisur;Faqeerzada, Mohammad Akbar;Joshi, Rahul;Cho, Byoung-Kwan
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2017.04a
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    • pp.44-44
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    • 2017
  • The objective of this study was to evaluate firmness, and sweetness index (SI) of tomatoes (Lycopersicum esculentum) by using hyperspectral imaging (HSI) in the range of 1000-1400 nm. The mean spectra of the 95 matured tomato samples were extracted from the hyperspectral images, and the reference firmness and sweetness index of the same sample were measured and calibrated with their corresponding spectral data by partial least squares (PLS) regression with different preprocessing method. The results showed that the regression model developed by PLS regression based on Savitzky-Golay (S-G) second-derivative preprocessed spectra resulted in better performance for firmness, and SI of tomatoes compared to models developed by other preprocessing methods, with correlation coefficients (rpred) of 0.82, and 0.74 with standard error of prediction (SEP) of 0.86 N, and 0.63 respectively. Then, the feature wavelengths were identified using model-based variable selection method, i.e., variable important in projection (VIP), resulting from the PLS regression analyses and finally chemical images were derived by applying the respective regression coefficient on the spectral image in a pixel-wise manner. The resulting chemical images provided detailed information on firmness, and sweetness index (SI) of tomatoes. Therefore, these research demonstrated that HIS technique has a potential for rapid and non-destructive evaluation of the firmness and sweetness index of tomatoes.

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3DTIP: 3D Stereoscopic Tour-Into-Picture of Korean Traditional Paintings (3DTIP: 한국 고전화의 3차원 입체 Tour-Into-Picture)

  • Jo, Cheol-Yong;Kim, Man-Bae
    • Journal of Broadcast Engineering
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    • v.14 no.5
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    • pp.616-624
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    • 2009
  • This paper presents a 3D stereoscopic TIP (Tour Into Picture) for Korean classical paintings being composed of persons, boat, and landscape. Unlike conventional TIP methods providing 2D image or video, our proposed TIP can provide users with 3D stereoscopic contents. Navigating a picture with stereoscopic viewing can deliver more realistic and immersive perception. The method firstly makes input data being composed of foreground mask, background image, and depth map. The second step is to navigate the picture and to obtain rendered images by orthographic or perspective projection. Then, two depth enhancement schemes such as depth template and Laws depth are utilized in order to reduce a cardboard effect and thus to enhance 3D perceived depth of the foreground objects. In experiments, the proposed method was tested on 'Danopungjun' and 'Muyigido' that are famous paintings made in Chosun Dynasty. The stereoscopic animation was proved to deliver new 3D perception compared with 2D video.

A Study on Fingerprinting Robustness Indicators for Immersive 360-degree Video (실감형 360도 영상 특징점 기술 강인성 지표에 관한 연구)

  • Kim, Youngmo;Park, Byeongchan;Jang, Seyoung;Yoo, Injae;Lee, Jaechung;Kim, Seok-Yoon
    • Journal of IKEEE
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    • v.24 no.3
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    • pp.743-753
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    • 2020
  • In this paper, we propose a set of robustness indicators for immersive 360-degree video. With the full-fledged service of mobile carriers' 5G networks, it is possible to use large-capacity, immersive 360-degree videos at high speed anytime, anywhere. Since it can be illegally distributed in web-hard and torrents through DRM dismantling and various video modifications, however, evaluation indicators that can objectively evaluate the filtering performance for copyright protection are required. In this paper, a robustness indicators is proposed that applies the existing 2D Video robustness indicators and considers the projection method and reproduction method, which are the characteristics of Immersive 360-degree Video. The performance evaluation experiment has been carried out for a sample filtering system and it is verified that an excellent recognition rate of 95% or more has been achieved in about 3 second execution time.

Excretroy Urography in the Minipig (미니돼지에서 배설성요로조영술의 적용)

  • Jung, Joo-Hyun;Chang, Jin-Hwa;Choi, Min-Cheol
    • Journal of Life Science
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    • v.17 no.9 s.89
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    • pp.1211-1216
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    • 2007
  • Excretory urography was performed on eight healthy minipigs to evaluate radiographic anatomical status and excretive function of the urinary tracts and to get an optimal procedure. The right and left kidneys were located in $T13{\sim}L4$and $T12{\sim}L3.5$, respectively. The left kidneys were located more cra-nially than the right. The everage lengths and widths of kidneys were $8.50{\pm}0.58$ $(mean{\pm}SD)$and $4.30{\pm}0.39$ cm on the ventrodorsal projection and $8.70{\pm}0.76$, and $4.10{\pm}0.40$ cm on the lateral projection, respectively. The lengths of kidneys were twice the width. When the lengths of kidneys were com-pared with lengths of the second lumbar vertebras, the ratios of kidney lengths to L2 lengths were $3.62{\pm}0.30$ on the ventrodorsal projection and $3.63{\pm}1.10$ on the lateral projection. The lengths and 쟝손 of renal pelvis including major calices were $4.01{\pm}0.46$, and 2.20{\pm}0.41$ cm, respectively. The lengths and 쟝손 of minor calices were $0.49{\pm}0.06$, and $0.10{\pm}0.01$ cm. The lengths and widths of the ureters were $12.25{\pm}2.05$, and 2.94{\pm}0.86$ cm. The nephrogram stage was reached in 3{\sim}5$ minutes, and the pyelogram phase in $5{\sim}15$ minutes individually after injection of contrast medium. The result of this study shows similar information and procedure of excretory urography for other laboratory ani-mals and leads to the potential use of this method for minipigs.