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Surface Rendering in Abdominal Aortic Aneurysm by Deformable Model (복부대동맥의 3차원 표면모델링을 위한 가변형 능동모델의 적용)

  • Choi, Seok-Yoon;Kim, Chang-Soo
    • The Journal of the Korea Contents Association
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    • v.9 no.6
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    • pp.266-274
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    • 2009
  • An abdominal aortic aneurysm occurs most commonly in older individuals (between 65 and 75), and more in men and smokers. The most important complication of an abdominal aortic aneurysm is rupture, which is most often a fatal event. An abdominal aortic aneurysm weakens the walls of the blood vessel, leaving it vulnerable to bursting open, or rupturing, and spilling large amounts of blood into the abdominal cavity. surface modeling is very useful to surgery for quantitative analysis of abdominal aortic aneurysm. the 3D representation and surface modeling an abdominal aortic aneurysm structure taken from Multi Detector Computed Tomography. The construction of the 3D model is generally carried out by staking the contours obtained from 2D segmentation of each CT slice, so the quality of the 3D model strongly defends on the precision of segmentation process. In this work we present deformable model algorithm. deformable model is an energy-minimizing spline guided by external constraint force. External force which we call Gradient Vector Flow, is computed as a diffusion of a gradient vectors of gray level or binary edge map derived from the image. Finally, we have used snakes successfully for abdominal aortic aneurysm segmentation the performance of snake was visually and quantitatively validated by experts.

Design of Face Recognition Algorithm based Optimized pRBFNNs Using Three-dimensional Scanner (최적 pRBFNNs 패턴분류기 기반 3차원 스캐너를 이용한 얼굴인식 알고리즘 설계)

  • Ma, Chang-Min;Yoo, Sung-Hoon;Oh, Sung-Kwun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.6
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    • pp.748-753
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    • 2012
  • In this paper, Face recognition algorithm is designed based on optimized pRBFNNs pattern classifier using three-dimensional scanner. Generally two-dimensional image-based face recognition system enables us to extract the facial features using gray-level of images. The environmental variation parameters such as natural sunlight, artificial light and face pose lead to the deterioration of the performance of the system. In this paper, the proposed face recognition algorithm is designed by using three-dimensional scanner to overcome the drawback of two-dimensional face recognition system. First face shape is scanned using three-dimensional scanner and then the pose of scanned face is converted to front image through pose compensation process. Secondly, data with face depth is extracted using point signature method. Finally, the recognition performance is confirmed by using the optimized pRBFNNs for solving high-dimensional pattern recognition problems.

Feature Selection of Training set for Supervised Classification of Satellite Imagery (위성영상의 감독분류를 위한 훈련집합의 특징 선택에 관한 연구)

  • 곽장호;이황재;이준환
    • Korean Journal of Remote Sensing
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    • v.15 no.1
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    • pp.39-50
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    • 1999
  • It is complicate and time-consuming process to classify a multi-band satellite imagery according to the application. In addition, classification rate sensitively depends on the selection of training data set and features in a supervised classification process. This paper introduced a classification network adopting a fuzzy-based $\gamma$-model in order to select a training data set and to extract feature which highly contribute to an actual classification. The features used in the classification were gray-level histogram, textures, and NDVI(Normalized Difference Vegetation Index) of target imagery. Moreover, in order to minimize the errors in the classification network, the Gradient Descent method was used in the training process for the $\gamma$-parameters at each code used. The trained parameters made it possible to know the connectivity of each node and to delete the void features from all the possible input features.

Camera Model Identification Based on Deep Learning (딥러닝 기반 카메라 모델 판별)

  • Lee, Soo Hyeon;Kim, Dong Hyun;Lee, Hae-Yeoun
    • KIPS Transactions on Software and Data Engineering
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    • v.8 no.10
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    • pp.411-420
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    • 2019
  • Camera model identification has been a subject of steady study in the field of digital forensics. Among the increasingly sophisticated crimes, crimes such as illegal filming are taking up a high number of crimes because they are hard to detect as cameras become smaller. Therefore, technology that can specify which camera a particular image was taken on could be used as evidence to prove a criminal's suspicion when a criminal denies his or her criminal behavior. This paper proposes a deep learning model to identify the camera model used to acquire the image. The proposed model consists of four convolution layers and two fully connection layers, and a high pass filter is used as a filter for data pre-processing. To verify the performance of the proposed model, Dresden Image Database was used and the dataset was generated by applying the sequential partition method. To show the performance of the proposed model, it is compared with existing studies using 3 layers model or model with GLCM. The proposed model achieves 98% accuracy which is similar to that of the latest technology.

Optical Encryption of Binary Information using 2-step Phase-shifting Digital Holography (2-단계 위상 천이 디지털 홀로그래피를 이용한 이진 정보 광 암호화 기법)

  • Byun, Hyun-Joong;Gil, Sang-Keun
    • Korean Journal of Optics and Photonics
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    • v.17 no.5
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    • pp.401-411
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    • 2006
  • We propose an optical encryption/decryption technique for a security system based on 2-step phase-shifting digital holography. Phase-shilling digital holography is used for recording phase and amplitude information on a CCD device. 2-step phase-shifting is implemented by moving the PZT mirror with phase step of 0 or ${\pi}/2$. The binary data and the key are expressed with random code and random phase patterns. The digital hologram is a Fourier transform hologram and is recorded on CCD with 256 gray level quantization. We remove the DC term of the digital hologram fur data reconstruction, which is essential to reconstruct the original binary input data/image. The error evaluation fer the decrypted binary data is analyzed. One of errors is a quantization error in detecting the hologram intensity on CCD, and the other is generated from decrypting the data with the incorrect key. The technique using 2-step phase-shifting holography is more efficient than a 4-step method because 2-step phase-shifting holography system uses less data than the 4-step method for data storage or transmission. The simulation shows that the proposed technique gives good results fur the optical encryption of binary information.

Convolutional Neural Network with Expert Knowledge for Hyperspectral Remote Sensing Imagery Classification

  • Wu, Chunming;Wang, Meng;Gao, Lang;Song, Weijing;Tian, Tian;Choo, Kim-Kwang Raymond
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.8
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    • pp.3917-3941
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    • 2019
  • The recent interest in artificial intelligence and machine learning has partly contributed to an interest in the use of such approaches for hyperspectral remote sensing (HRS) imagery classification, as evidenced by the increasing number of deep framework with deep convolutional neural networks (CNN) structures proposed in the literature. In these approaches, the assumption of obtaining high quality deep features by using CNN is not always easy and efficient because of the complex data distribution and the limited sample size. In this paper, conventional handcrafted learning-based multi features based on expert knowledge are introduced as the input of a special designed CNN to improve the pixel description and classification performance of HRS imagery. The introduction of these handcrafted features can reduce the complexity of the original HRS data and reduce the sample requirements by eliminating redundant information and improving the starting point of deep feature training. It also provides some concise and effective features that are not readily available from direct training with CNN. Evaluations using three public HRS datasets demonstrate the utility of our proposed method in HRS classification.

Effects of Zingiberis Rhizoma Pharmacopuncture Injected at GB30 and ST36 on Neuropathic Pain in Rats (환도(GB30) 및 족삼리(ST36) 건강약침이 신경병증성 통증 유발 흰쥐에 미치는 영향)

  • Hwang, Min Sub
    • Korean Journal of Acupuncture
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    • v.36 no.1
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    • pp.52-62
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    • 2019
  • Objectives : The objective of this study was to investigate the effects of Zingiberis Rhizoma Pharmacopuncture(ZP) at GB30 and ST36 in neuropathic pain induced SD rats by the block of Transient Receptor Potential Vanilloid 1(TRPV1). Methods : Neuropathic pain in rats was induced by tibial and common peroneal nerve transection of right leg. The rat subjects were divided into 6 groups : normal(Nor, n=5), control(Con, n=5), neuropathic pain plus 2 mg/kg ZP injection at GB30 and ST36(ZP-A, n=5), 10 mg/kg ZP(ZP-B, n=5), 20 mg/kg ZP(ZP-C, n=5) and 0.45 mg/kg Tramadol(Tra, n=5). Three days after the surgery, injections were administered once a day for 17 days. Withdrawal response of neuropathic rats' legs were measured by stimulating the paw of Right leg with von frey filament, acetone and radient heat on day 3, 7, 11, 15, 19 after surgery. After all treatments were completed, c-Fos in the midbrain central gray and TRPV1 & TRPA1 of DRG(L5) were analyzed. Results : Groups ZP-B and ZP-C showed a meaningful decrease in the withdrawal response of mechanical allodynia, thermal hyperalgesia and cold allodynia compared to the control group(p<0.05, p<0.01, p<0.001). Groups ZP-B and ZP-C showed a meaningful decrease in the expression of c-fos and TRPV1 protein level compared to the control group(p<0.05, p<0.01, p<0.001). Conclusions : These results suggest that Zingiberis Rhizoma Pharmacopuncture at GB30 and ST36 could decrease mechanical & cold allodynia and thermal hyperalgesia by block the TRPV1 on the model of neuropathic pain.

A Study on the Granulometry and Chemical Composition of Psudo-Gleized Soil in Jeongdongjin Area (정동진 의사글레이층의 입도와 화학 조성에 대한 연구)

  • Kim, Jong Yeon
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.3
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    • pp.27-45
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    • 2017
  • At the upper part of terrace deposits at Jeongdongjin area, there is a structure in which reddish brown and grayish white layers laying horizontally. Previous studies have reported the existence of these structures within the deposits and suggested the theoretical background related to the formation process. However, the analysis of physical properties and chemical composition such as particle size, classification, etc. of the materials constituting the reddish brown and grayish white layers is scarcely done. In this study, the physico - chemical properties of gray - white and reddish brown beds are investigated. The mean grain size of the particles was less than $4{\varphi}$ in both layers and the reddish brown layer was more coarse. The results shows that the sorting of the grayish white layer is better. The chemical composition of both layers shows that the average concentration of $SiO_2$, $Al_2O_3$ and $K_2O$ of the grayish white layer was higher than those of the reddish brown layer. The concentration of $Fe_2O_3$ of reddish brown lyaer was 3 times higher than those of the grayish white layer. The degree of chemical weathering (CIA) is 90 or so in both the reddish brown and grayish white layers, indicating a significant level of chemical weathering. In conclusion, reddish brown layers had been formed by the processes related to the migration of iron and the migration of water that induced aggregation after the formation of sediments (psudo-gleization). In this study area, a vertical layer of grayish white which cuts off horizontal reddish brown and grayish white color was found. The vertical layer or wedge similar to a ice-wedge or columnar structure that in a cold environment, and there is a difference in shape and size. The vertical layer appears to have occurred three or more cycles. The vertical layers begin to form at a certain height within the outcrop and descend downwards, which of course is difficult to see as directing certain times.

Bone Microarchitecture at the Femoral Attachment of the Posterior Cruciate Ligament (PCL) by Texture Analysis of Magnetic Resonance Imaging (MRI) in Patients with PCL Injury: an Indirect Reflection of Ligament Integrity

  • Kim, Hwan;Shin, YiRang;Kim, Sung-Hwan;Lee, Young Han
    • Investigative Magnetic Resonance Imaging
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    • v.25 no.2
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    • pp.93-100
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    • 2021
  • Purpose: (1) To evaluate the trabecular pattern at the femoral attachment of the posterior cruciate ligament (PCL) in patients with a PCL injury; (2) to analyze bone microarchitecture by applying gray level co-occurrence matrix (GLCM)-based texture analysis; and (3) to determine if there is a significant relationship between bone microarchitecture and posterior instability. Materials and Methods: The study included 96 patients with PCL tears. Trabecular patterns were evaluated on T2-weighted MRI qualitatively, and were evaluated by GLCM texture analysis quantitatively. The grades of posterior drawer test (PDT) and the degrees of posterior displacement on stress radiographs were recorded. The 96 patients were classified into two groups: acute and chronic injury. And 27 patients with no PCL injury were enrolled for control. Pearson's correlation coefficient and one-way ANOVA with Bonferroni test were conducted for statistical analyses. This protocol was approved by the Institutional Review Board. Results: A thick and anisotropic trabecular bone pattern was apparent in normal or acute injury (n = 57/61;93.4%), but was not prominent in chronic injury and posterior instability (n = 31/35;88.6%). Grades of PDT and degrees of posterior displacement on stress radiograph were not correlated with texture parameters. However, the texture analysis parameters of chronic injury were significantly different from those of acute injury and control groups (P < 0.05). Conclusion: The trabecular pattern and texture analysis parameters are useful in predicting posterior instability in patients with PCL injury. Evaluation of the bone microarchitecture resulting from altered biomechanics could advance the understanding of PCL function and improve the detection of PCL injury.

Changing Identities and the Legacy of Black Fanaticism in The Confessions of Nat Turner and Two Films Entitled The Birth of a Nation

  • Jin, Seongeun
    • Journal of English Language & Literature
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    • v.64 no.3
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    • pp.453-468
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    • 2018
  • Nat Turner's rebellion in 1831 was considered pre Civil War South's most dreadful nightmare due to the merciless murder of white slave owner victims. The motive of vengeance has been emphasized as that of Turner's notorious black preacher religious fanaticism. However, the recent film, The Birth of a Nation (2016) directed by Nate Parker, utilized the identical title of a film (1915) directed by D. W. Griffith. Providing limited evidence, information about the rebellion in Thomas Gray's pamphlet The Confessions of Nat Turner (1831), was the only accessible historical source for the factual event of the slaves' rebellion. In addition, William Styron's The Confessions of Turner (1967), a fictionalized biography, also examined Turner's life in the harshness of slavery. Although these two texts deal with the personal level of Nat Turner's rage and religious enthusiasm, both provide only fractured parts of the motive of vengeance. Strikingly, Parker's film interrogates the ideology of "victims," as well as the hierarchical term of "confessions," with their different positions between whites and blacks. More specifically, Parker's film offers discursive fields of proslavery arguments regarding biblical interpretations in addition to external visualization of slaves' inner emotional lives. The film demonstrates how the institution of slavery allowed slaves to be exploited, beaten, raped, through interrogating the problematic image of the "contested hero" Nat Turner. In contrast to the traditional image of blacks' bloody rebellion, the film underlines the absurdity of certain Biblical misinterpretations. It furthermore implies how the 1915 film manipulated proslavery propaganda in America.