• Title/Summary/Keyword: correlation function method

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Text Verification Based on Sub-Image Matching (부분 영상 매칭에 기반한 텍스트 검증)

  • Son Hwa Jeong;Jeong Seon Hwa;Kim Soo Hyung
    • The KIPS Transactions:PartB
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    • v.12B no.2 s.98
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    • pp.115-122
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    • 2005
  • The sub-mage matching problem in which one image contains some part of the other image, has been mostly investigated on natural images. In this paper, we propose two sub-image matching techniques: mesh-based method and correlation-based method, that are efficiently used to match text images. Mesh-based method consists of two stages, box alignment and similarity measurement by extracting the mesh feature from the two images. Correlation-based method determines the similarity using the correlation of the two images based on FFT function. We have applied the two methods to the text verification in a postal automation system and observed that the accuracy of correlation-based method is $92.7\%$ while that of mesh-based method is $90.1\%$.

A Systematic Review of the Correlation between Hand Dexterity and Cognitive Function in Elderly (노인의 손의 기민성과 인지기능과의 상관성에 대한 체계적 문헌고찰)

  • Ho-Soung Kwak
    • Journal of The Korean Society of Integrative Medicine
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    • v.11 no.3
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    • pp.49-57
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    • 2023
  • Purpose : This study aimed to systematically review the correlation between hand dexterity and cognitive function in the elderly, and summarize various evaluation tests and results analysis methods for manual dexterity tests applied to this population. Methods : We searched published studies in the Korean Studies Information Service System and PubMed databases from January 2013 to March 2023. The main keywords used were "dexterity," "fine motor," "elderly," "cognitive function," and "correlation." A total of 10 studies were selected for analysis from the 1,524 searched articles. The included studies consisted of a cohort study, a longitudinal study, and eight cross-sectional studies which were analyzed for patients, intervention, comparison, and outcomes. Results : Analyzing the qualitative level of 10 studies, 8 articles (80%) were non-randomized two-group studies that provided level II evidence whereas the remaining 2 studies (20%) were non-randomized single-group studies (level III evidence). Therefore, these results indicated that the level of evidence in this field is generally high. The Purdue pegboard test was the most commonly used evaluation test for manual dexterity, and velocity speed was the most frequently employed analysis method. Results indicated that there were significant differences in manual dexterity test between the normal elderly, those with mild cognitive impairment, or dementia. Conclusions : These results can be used as a basis for selecting dexterity test evaluation items and methods to analyze it in the elderly while screening for cognitive impairment. In addition, this study highlights potential areas for future research on the development of manual dexterity evaluation tools and techniques for analysis and the need for more reliable and valid methods for assessing cognitive function in the elderly.

Quantitative evaluation of rabbit's hepatic function using HEF, DISIDA-K, and R-max technique (HEF, DISIDA-K, R-max 방법을 이용한 토끼 간 기능의 정량적 평가)

  • Kim, D.W.;Kim, S.C.;Yun, S.J.;Lee, J.D.;Kim, B.R.
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.05
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    • pp.161-163
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    • 1996
  • The correlation coefficients among hepatic extraction fraction(HEF), DISIDA-K, and ICG Rmax methods were found using two normal rabbits and four rabbits with damaged liver. The correlation coefficient between HEF and ICG R-max which is a standard technique in evaluating liver function was found to be 0.93. Therefore HEF is a valuable diagnostic method since it is not only accurate, but possible to estimate remaining liver function after surgical of cancerous hepatic tissue.

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Influencing Factors of Mentoring on Nursing Students (멘토링의 영향요인: 간호대학생을 대상으로)

  • Seol-Young Bang
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.5
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    • pp.733-741
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    • 2023
  • The purpose his study was a descriptive research study to identify the influencing factors of mentoring for nursing students, and was conducted with 120 nursing students. The collected data were subjected to real number and percentage, mean and standard deviation, t-test, ANOVA, Scheffe test, Pearson's correlation, and multiple regression analysis using SPSS/WIN 25.0. As a result of the study, mentoring was found to have a significant positive correlation with organizational socialization, core nursing competency, and clinical performance competency, and the explanatory power of the regression model was 64.1%. Since mentoring is an effective teaching method, based on this study, we propose a study to develop a structured mentoring program including organizational socialization, core nursing competency, and clinical performance competency to test the effectiveness. In addition, proposes a study to identify the relationship with various variables by dividing mentoring into sub-competencies of career development function, psychological stability function, and role model function.

Binarization Based on the Spatial Correlation of Gray Levles (그레이 레벨의 공간적 상관관계 기반 이진화)

  • Seo, Suk-T.;Son, Seo-H.;Lee, In-K.;Jeong, Hye-C.;Kwon, Soon-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.4
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    • pp.466-471
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    • 2007
  • Conventional thresholding methods including Otsu's thresholding method are based on the gray levels frequency histogram. But the gray levels frequency histogram is obtained by recomposing only frequency information from an input image, where frequency histogram dose not contain any other informations such as the distribution of gray levels and relation between gray levels. Therefore the methods using the gray levels frequency histogram occasionally present inappropriate threshold values because it cannot reflect informations of the given image sufficiently. In this paper, we define a correlation function of gray levels and propose a novel thresholding method using the gray levels frequency histogram and the spatial correlation information. The effectiveness of the proposed method will be shown through comparison with Otsu's thresholding method.

Wavelet-based automatic identification method of axle distribution information

  • Wang, Ning-Bo;Ren, Wei-Xin;Chen, Zhi-Wei
    • Structural Engineering and Mechanics
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    • v.63 no.6
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    • pp.761-769
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    • 2017
  • Accurately extracting the axle distribution information of a passing vehicle from bridge dynamic responses experiences a key and challenging step in non-pavement bridge weigh-in-motion (BWIM). In this article, the wavelet transformation is adopted and the wavelet coefficient curve is used as a substitute for dynamic response. The driving frequency is introduced and expanded to multi-axle vehicle, and the wavelet coefficient curve on specific scale corresponding to the driving frequency is confirmed to contain obvious axle information. On this basis, an automatic method for axle distribution information identification is proposed. The specific wavelet scale can be obtained through iterative computing, and the false peaks due to bridge vibration can be eliminated through cross-correlation analysis of the wavelet coefficients of two measure points. The integrand function that corresponds to the maximum value of the cross-correlation function is used to identify the peaks caused by axles. A numerical application of the proposed axle information identification method is carried out. Numerical results demonstrate that this method acquires precise axle information from the responses of an axle-insensitive structure (e.g., girder) and decreases the requirement of sensitivity structure of BWIM. Finally, an experimental study on a full-scale simply supported bridge is also conducted to verify the effectiveness of this method.

Identification of isotropic and orthotropic constitutive parameters by FEA-free energy-based inverse characterization method

  • Shang, Shen;Yun, Gun Jin;Kunchum, Shilpa;Carletta, Joan
    • Structural Engineering and Mechanics
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    • v.45 no.4
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    • pp.471-494
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    • 2013
  • In this paper, identification of isotropic and orthotropic linear elastic material constitutive parameters has been demonstrated by a FEA-free energy-based inverse analysis method. An important feature of the proposed method is that it requires no finite element (FE) simulation of the tested material. Full-field displacements calculated using digital image correlation (DIC) are used to compute DIC stress fields enforcing the equilibrium condition and DIC strain fields using interpolation functions. Boundary tractions and displacements are implicitly recast into an objective function that measures the energy residual of external work and internal elastic strain energy. The energy conservation principle states that the residual should be zero, and so minimizing this objective function inversely identifies the constitutive parameters. Synthetic data from simulated testing of isotropic materials and orthotropic composite materials under 2D plane stress conditions are used for verification of the proposed method. When identifying the constitutive parameters, it is beneficial to apply loadings in multiple directions, and in ways that create non-uniform stress distributions. The sensitivity of the parameter identification method to noise in both the measured full-field DIC displacements and loadings has been investigated.

An Algorithm for Leak Locating using Coupled Vibration of Pipe-Water (배관-유체 연성진동을 이용한 누수지점 탐지알고리듬 개발연구)

  • Lee, Yeong-Seop;Yun, Dong-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.985-990
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    • 2004
  • Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband noise from a leak location and can be propagated to both directions of water pipes. This sound propagation due to leak in water pipelines is not a non-dispersive wave any more because of the surrounding pipes and soil. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300m.

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An Algorithm for Leak Locating using Coupled Vibration of Pipe-Fluid (배관-유체 연성진동을 이용한 누수지점 탐지 알고리듬 개발 연구)

  • Lee, Young-Sup;Yoon, Dong-Jin
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.798-803
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    • 2004
  • Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband sound from a leak location and this sound propagation due to leak in water pipelines is not a non-dispersive wave any more because of the surrounding pipes and soil. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300m.

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Time Delay Estimation for the Identification of Leak Location (시간지연 추정을 통한 누수위치 식별 연구)

  • Lee, Young-Sup;Yoon, Dong-Jin;Kim, Chi-Yup
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.327-332
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    • 2004
  • Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband noise from a leak location and can be propagated to both directions of water pipes. This sound propagation due to leak in water pipelines is not a non-dispersive wave any more because of the surrounding pipes and soil. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than loom.

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