• Title/Summary/Keyword: 총변이 정규화

Search Result 6, Processing Time 0.021 seconds

An Unified Bayesian Total Variation Regularization Method and Application to Image Restoration (통합 베이즈 총변이 정규화 방법과 영상복원에 대한 응용)

  • Yoo, Jae-Hung
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.17 no.1
    • /
    • pp.41-48
    • /
    • 2022
  • This paper presents the unified Bayesian Tikhonov regularization method as a solution to total variation regularization. The integrated method presents a formula for obtaining the regularization parameter by transforming the total variation term into a weighted Tikhonov regularization term. It repeats until the reconstructed image converges to obtain a regularization parameter and a new weighting factor based on it. The experimental results show the effectiveness of the proposed method for the image restoration problem.

Gaussian Noise Reduction Method using Adaptive Total Variation : Application to Cone-Beam Computed Tomography Dental Image (적응형 총변이 기법을 이용한 가우시안 잡음 제거 방법: CBCT 치과 영상에 적용)

  • Kim, Joong-Hyuk;Kim, Jung-Chae;Kim, Kee-Deog;Yoo, Sun-K.
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.49 no.1
    • /
    • pp.29-38
    • /
    • 2012
  • The noise generated in the process of obtaining the medical image acts as the element obstructing the image interpretation and diagnosis. To restore the true image from the image polluted from the noise, the total variation optimization algorithm was proposed by the R.O. F (L.Rudin, S Osher, E. Fatemi). This method removes the noise by fitting the balance of the regularity and fidelity. However, the blurring phenomenon of the border area generated in the process of performing the iterative operation cannot be avoided. In this paper, we propose the adaptive total variation method by mapping the control parameter to the proposed transfer function for minimizing boundary error. The proposed transfer function is determined by the noise variance and the local property of the image. The proposed method was applied to 464 tooth images. To evaluate proposed method performance, PSNR which is a indicator of signal and noise's signal power ratio was used. The experimental results show that the proposed method has better performance than other methods.

Identification of Foreign Objects in Soybeans Using Near-infrared Spectroscopy (근적외선 분광법을 이용한 콩과 이물질의 판별)

  • Lim, Jong-Guk;Kang, Sukwon;Lee, Kangjin;Mo, Changyeon;Son, Jaeyong
    • Food Engineering Progress
    • /
    • v.15 no.2
    • /
    • pp.136-142
    • /
    • 2011
  • The objective of this research was to classify intact soybeans and foreign objects using near-infrared (NIR) spectroscopy. Intact soybeans and foreign objects were scanned using a NIR spectrometer equipped with scanning monochromator. NIR spectra of intact soybeans and foreign objects in the wavelength range from 900 to 1800 nm were collected. The classification of intact soybeans and foreign objects were conducted by using partial least-square discriminant analysis (PLS-DA) and soft independent modelling of class analogy (SIMCA) multivariate methods. Various types of data pretreatments were tested to develop the classification models. Intact soybeans and foreign objects were successfully classified by the PLS-DA prediction model with mean normalization pretreatment. These results showed the potential of NIR spectroscopy combined with multivariate analysis as a method for classifying intact soybeans and foreign objects.

Variation of Saponin Content in Korean Native Soybean Landraces Reintroduced from USA to Korea (미국으로부터 재도입된 한국 원산 콩 재래종의 Saponin 함량 변이)

  • Jang, Eun-Kyu;Piao, Xiangmin;Hwang, Tae-Young;Kim, Sun-Lim;Chung, Gyu-Hwa;Tsukamoto, Chigen;Choi, Yu-Mi;Lee, Myung-Chul;Lee, Jeong-Ran;Kim, Hong-Sig
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.57 no.3
    • /
    • pp.286-295
    • /
    • 2012
  • This study was carried out to assess the variation of saponin contents in 293 Korean native soybean landraces reintroduced from USA to Korea in 2007. Group A saponin content ranged from 149.8 ${\mu}g\;g^{-1}$ to 1279.0 ${\mu}g\;g^{-1}$ with an average of 484.9 ${\mu}g\;g^{-1}$. Group B saponin content ranged from 2160.1 ${\mu}g\;g^{-1}$ to 7868.6 ${\mu}g\;g^{-1}$ with an average of 3670.0 ${\mu}g\;g^{-1}$. Total saponin content including both group A and B contents ranged from 2502.8 to 8764.0 ${\mu}g\;g^{-1}$ with an average of 4154.9 ${\mu}g\;g^{-1}$. Five promising landraces for use as breeding materials that showed higher than any other landraces in group B and total saponin content were IT226841, IT226761, IT226841, IT226828 and IT228534. IT226841 showed the highest saponin content with group B content of 7868.5 ${\mu}g\;g^{-1}$ and total saponin content of 8764.0 ${\mu}g\;g^{-1}$ among landraces. In the relationship among each components, group A saponin content showed a positive correlation with group B saponin content (r=0.3708) and total saponin content (r=0.5119). Group B saponin content showed a very high positive correlation (r=0.9876) with total saponin content. When landraces were compared for the total saponin content based on collected location, landraces from North Korea showed the highest, Gyeonggi-do showed second highest content, followed by Chungcheongbuk-do, Gangwon-do, Gyongsangbuk-do, Chungcheongnam-do, Gyongsangnam-do, Jeollabuk-do and Jeollanam-do. Landraces were also grouped according to seed size and seed coat color. Small seed group was higher than medium and large seed groups that showed no significant difference in total saponin content. Seed coat colors showed no significant difference in total saponin content.

Comparison of the Plant Characteristics and Nutritional Components between GM and Non-GM Chinese Cabbages Grown in the Central and Northern Parts of Korea (중·북부지역에서 재배된 GM 배추와 Non-GM 배추간의 식물체 특성 및 영양 성분 비교 분석)

  • Cho, Dong-Wook;Oh, Jin-Pyo;Park, Kuen-Woo;Lee, Dong-Jin;Chung, Kyu-Hwan
    • Horticultural Science & Technology
    • /
    • v.28 no.5
    • /
    • pp.836-844
    • /
    • 2010
  • This study was carried out to investigate plant characteristics and nutritional components of the genetically modified (GM) Chinese cabbage and its control line grown in the central and northern parts of Korea in order to establish the evaluating protocol and standard assessment. The GM and non-GM Chinese cabbage was planted with normal and concentrated density at two locations in spring and fall of 2008 and 2009. From the statistic analysis on plant characteristics and nutritional components, there were not many significant differences between GM and non-GM Chinese cabbage. Only few differences in the plant characteristics were found between the dense and normal planting. In the dense planting, there was no significant difference between GM and non-GM Chinese cabbages except for three out of 18 plant traits, such as leaf shape, hairiness and midrib length. On the other hand, nine plant traits including leaf length, leaf width, leaf color, leaf shape, fresh weigh of ground part, number of leaf, midrib length, midrib width and root diameter were slightly different between GM and non-GM Chinese cabbage in the normal planting. In case of leaf length, midrib length, midrib width and fresh weigh of ground part, there were significantly differences not only between two lines, but also between two locations. From nutritional component analysis, only five fatty acids were identified in the Chinese cabbage: palmitic acid, oleic acid, stearic acid, linoleic acid and linolenic acid. Except linoleic acid, four fatty acids in one gram of dried sample from GM line were little higher than those from non-GM line. However, there were no significant differences in total contents of fatty acids not only between GM and non-GM Chinese cabbage line, but also between northern and central cultivating areas in the normal and dense planting. According to the composition of inorganic elements identified in the samples from both lines, there were six macro-elements, such as N, P, Ca, K, Mg and Na, and four micro-elements, Cu, Fe, Mn and Zn. Based on the result from PCA analysis, specific clusters were not found between GM Chinese cabbage and the control line, but found between two regions.

Impact of Pulmonary Vascular Compliance on the Duration of Pleural Effusion Duration after Extracardiac Fontan Procedure (수술 전 폐혈관 유순도가 심장 외 도판을 이용한 Fontan 수술 후 늑막 삼출 기간에 미치는 영향)

  • Yun Tae-Jin;Im Yu-Mi;Song Kwang-Jae;Jung Sung-Ho;Park Jeong-Jun;Seo Dong-Man;Lee Moo-Song
    • Journal of Chest Surgery
    • /
    • v.39 no.8 s.265
    • /
    • pp.579-587
    • /
    • 2006
  • Background: Preoperative risk analysis for Fontan candidates is still less than optimal in that patients with apparently low risks may have poor surgical outcome; prolonged pleural drainage, protein losing enteropathy, pulmonary thromboembolism and death. We hypothesized that low pulmonary vascular compliance (PVC) is a risk factor for prolonged pleural effusion drainage after the Fontan operation. Material and Method: A retrospective review of 96 consecutive patients who underwent the Extracardiac Fontan procedures (median age: 3.9 years) was performed. Fontan risk score (FRS) was calculated from 12 categorized preoperative anatomic and physiologic variables. PVC $(mm^2/m^2{\cdot}mmHg)$ was defined as pulmonary artery index $(mm^2/m^2)$ divided by total pulmonary resistance $(W.U{\cdot}/m^2)$ and pulmonary blood flow $(L/min/m^2)$ based on the electrical circuit analogue of the pulmonary circulation. Chest tube indwelling time was log-transformed (log indwelling time, LIT) to fit normal distribution, and the relationship between preoperative predictors and LIT was analyzed by multiple linear regression. Result: Preoperative PVC, chest tube indwelling time and LIT ranged from 6 to 94.8 $mm^2/mmHg/m^2$ (median: 24.8), 3 to 268 days (median: 20 days), and 1.1 to 5.6 (mean: 2.9, standard deviation: 0.8), respectively. FRS, PVC, cardiopulmonary bypass time (CPB) and central venous pressure at postoperative 12 hours were correlated with LIT by univariable analyses. By multiple linear regression, PVC (p=0.0018) and CPB (p=0.0024) independently predicted LIT, explaining 21.7% of the variation. The regression equation was LIT=2.74-0.0158 PVC+0.00658 CPB. Conclusion: Low pulmonary vascular compliance is an important risk factor for prolonged pleural effusion drainage after the extracardiac Fontan procedure.