• Title/Summary/Keyword: normalization method

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Methodological Review on Functional Neuroimaging Using Positron Emission Tomography (뇌기능 양전자방출단층촬영영상 분석 기법의 방법론적 고찰)

  • Park, Hae-Jeong
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.2
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    • pp.71-77
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    • 2007
  • Advance of neuroimaging technique has greatly influenced recent brain research field. Among various neuroimaging modalities, positron emission tomography has played a key role in molecular neuroimaging though functional MRI has taken over its role in the cognitive neuroscience. As the analysis technique for PET data is more sophisticated, the complexity of the method is more increasing. Despite the wide usage of the neuroimaging techniques, the assumption and limitation of procedures have not often been dealt with for the clinician and researchers, which might be critical for reliability and interpretation of the results. In the current paper, steps of voxel-based statistical analysis of PET including preprocessing, intensity normalization, spatial normalization, and partial volume correction will be revisited in terms of the principles and limitations. Additionally, new image analysis techniques such as surface-based PET analysis, correlational analysis and multimodal imaging by combining PET and DTI, PET and TMS or EEG will also be discussed.

Normalization Diagnosis of Aging Process on Partial Discharge Signals of CV Cable (CV케이블의 부분방전 신호를 통한 열화과정의 정량적 진단)

  • 소순열;임장섭;김진사;이준웅;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.11a
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    • pp.451-455
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    • 1997
  • The partial discharge has been blown as the chief breakdown of power equipments. The analysis and the recognition is much difficult because the partial discharge signal is very small and has complex aging pattern. Recently, insulation aging diagnosis based on pattern of phase(Ф), partial discharge magnitude(q), number(n) has been very important. Owing to depreciate the reappearance of aging progress at the electrical tree pattern and to be difficult to analyze visually, the study on partial discharge pattern is suggested to normalizing analysis method of partial discharge signals. This parer is purposed on prediction of life-time measurement of cv-cable, on decision of risk degree with normalization and real-time measurement of partial discharge signals for aging diagnosis of cv-cable. As normalizing the aging signals of electrical tree in cv-cable, it is able to confirm risk degree of insulation material with the distribution of Ф-q-n and recognize the process of aging pattern using neural network.

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Elastic α-12C Scattering with the Ground State of 16O at Low Energies in Effective Field Theory

  • Ando, Shung-Ichi
    • Journal of the Korean Physical Society
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    • v.73 no.10
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    • pp.1452-1457
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    • 2018
  • Inclusion of the ground state of $^{16}O$ is investigated for a study of elastic ${\alpha}-^{12}C$ scattering for the l = 0 channel at low energies in effective field theory. We employ a Markov chain Monte Carlo method for the parameter fitting and find that the uncertainties of the fitted parameters are significantly improved compared to those of our previous study. We then calculate the asymptotic normalization constants of the $0^+$ states of $^{16}O$ and compare them with the experimental data and the previous theoretical estimates. We discuss implications of the results of the present work.

Experimental validation of dynamic based damage locating indices in RC structures

  • Fayyadh, Moatasem M.;Razak, Hashim Abdul
    • Structural Engineering and Mechanics
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    • v.84 no.2
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    • pp.181-206
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    • 2022
  • This paper presents experimental modal analysis and static load testing results to validate the accuracy of dynamic parameters-based damage locating indices in RC structures. The study investigates the accuracy of different dynamic-based damage locating indices compared to observed crack patterns from static load tests and how different damage levels and scenarios impact them. The damage locating indices based on mode shape curvature and mode shape fourth derivate in their original forms were found to show anomalies along the beam length and at the supports. The modified forms of these indices show higher sensitivity in locating single and multi-cracks at different damage scenarios. The proposed stiffness reduction index shows good sensitivity in detecting single and multi-cracks. The proposed anomalies elimination procedure helps to remove the anomalies along the beam length. Also, the adoption of the proposed weighting method averaging procedure and normalization procedure help to draw the overall crack pattern based on the adopted set of modes.

Rank-level Fusion Method That Improves Recognition Rate by Using Correlation Coefficient (상관계수를 이용하여 인식률을 향상시킨 rank-level fusion 방법)

  • Ahn, Jung-ho;Jeong, Jae Yeol;Jeong, Ik Rae
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.29 no.5
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    • pp.1007-1017
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    • 2019
  • Currently, most biometrics system authenticates users by using single biometric information. This method has many problems such as noise problem, sensitivity to data, spoofing, a limitation of recognition rate. One method to solve this problems is to use multi biometric information. The multi biometric authentication system performs information fusion for each biometric information to generate new information, and then uses the new information to authenticate the user. Among information fusion methods, a score-level fusion method is widely used. However, there is a problem that a normalization operation is required, and even if data is same, the recognition rate varies depending on the normalization method. A rank-level fusion method that does not require normalization is proposed. However, a existing rank-level fusion methods have lower recognition rate than score-level fusion methods. To solve this problem, we propose a rank-level fusion method with higher recognition rate than a score-level fusion method using correlation coefficient. The experiment compares recognition rate of a existing rank-level fusion methods with the recognition rate of proposed method using iris information(CASIA V3) and face information(FERET V1). We also compare with score-level fusion methods. As a result, the recognition rate improve from about 0.3% to 3.3%.

A Study on Tire Surface Defect Detection Method Using Depth Image (깊이 이미지를 이용한 타이어 표면 결함 검출 방법에 관한 연구)

  • Kim, Hyun Suk;Ko, Dong Beom;Lee, Won Gok;Bae, You Suk
    • KIPS Transactions on Software and Data Engineering
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    • v.11 no.5
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    • pp.211-220
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    • 2022
  • Recently, research on smart factories triggered by the 4th industrial revolution is being actively conducted. Accordingly, the manufacturing industry is conducting various studies to improve productivity and quality based on deep learning technology with robust performance. This paper is a study on the method of detecting tire surface defects in the visual inspection stage of the tire manufacturing process, and introduces a tire surface defect detection method using a depth image acquired through a 3D camera. The tire surface depth image dealt with in this study has the problem of low contrast caused by the shallow depth of the tire surface and the difference in the reference depth value due to the data acquisition environment. And due to the nature of the manufacturing industry, algorithms with performance that can be processed in real time along with detection performance is required. Therefore, in this paper, we studied a method to normalize the depth image through relatively simple methods so that the tire surface defect detection algorithm does not consist of a complex algorithm pipeline. and conducted a comparative experiment between the general normalization method and the normalization method suggested in this paper using YOLO V3, which could satisfy both detection performance and speed. As a result of the experiment, it is confirmed that the normalization method proposed in this paper improved performance by about 7% based on mAP 0.5, and the method proposed in this paper is effective.

Studies on the Terpenoids in the Volatile Constituents of Liaoning Schisandra Chinensis Baillon

  • Hou, Dongyan;Zhang, Weihua;Hui, Ruihua
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.505-509
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    • 1995
  • The terpenoids in the volatile constituents of Liaoning Shcisandra Chinesis Baillon have been determined by the analytical method of GC/MS. Thirty terpenoids molecular structure were characterized. They are 11.89% monterpenes, 4.60% monoterpene oxides, 58.74% sesquiterpene hydrocarbons, and 1.62% oxygen-containing sesquiterpenoids in the total volatile constituents quantified by chromatograph. Among them, the sesquiterpene make up the characteristic constituents. Every terpenoid constituent percent content was obtained using area normalization method of HP-59970 chemstation.

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An Optimal Denormalization Method in Relational Database with Response Time Constraint (관계형 데이터베이스에서 응답시간에 제약이 있는 경우 최적 역정규화 방법)

  • 장영관
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.26 no.3
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    • pp.1-9
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    • 2003
  • Databases are central to business information systems and RDBMS is most widely used for the database system. Normalization was designed to control various anomalies (insert, update, delete anomalies). However, normalized database design does not account for the tradeoffs necessary for performance. In this research, I model a database design method considering denormalization of duplicating attributes in order to reduce frequent join processes. This model considers response time for processing each select, insert, update, delete transaction, and for treating anomalies. A branch and bound method is proposed for this model.

Normalization of the Misaligned Moire Pattern Using Fourier Transform (푸리에 변환을 이용한 미스얼라인된 Moire 무늬의 표준화)

  • Park, T.W.;Morimoto, Y.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.15 no.2
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    • pp.386-394
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    • 1995
  • The fringes developed by misalignment, an application of Moire method measuring small deformation of specimen, was transformed to frequency function. After that, theory of normalization was applied to derive the equations explaining the relation of the deformation and Moire fringes. Above all, the equations were produced to explain the rotation and increasing of fringes. In addition to that, the relation of fringe number and strain was illustated with the equations deduced from frequency function and geometrical method respectively. These two expressions were more effective than the used ones owing to the one can accommodate the other.

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A Study On the Rrobabilistic Nature of Fatigue Crack Propagation Life(I) -The Effect of Distribution of Initial Crack Size- (피로크랙 진전수명의 확률특성에 관한 연구 I -초기크랙길이 분포의 영향-)

  • 윤한용
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.1
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    • pp.138-144
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    • 1990
  • In order to understand the probabilistic nature of fatigue crack propagation, not only the calculation of failure probability and parameter sensitivity, but also the clarification of probabilistic nature of various parameters should be executed. Therefore a method to evalute synthetically the effect of each parameter on the distribution of fatigue crack propagation life is required. In this study, the effects of the initial crack size and other paramaters on the distribution of fatigue crack propagation life are discussed according to the appropriate normalization of the life distribution, the validity of this method is also shown. Such an investigation as the present work may be useful to understand the nature of the life distribution and to utilize the probailistic fracture mechanics.