• Title/Summary/Keyword: intensity profile

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Automatic Segmentation of the Prostate in MR Images using Image Intensity and Gradient Information (영상의 밝기값과 기울기 정보를 이용한 MR영상에서 전립선 자동분할)

  • Jang, Yj-Jin;Jo, Hyun-Hee;Hong, Helen
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.9
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    • pp.695-699
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    • 2009
  • In this paper, we propose an automatic prostate segmentation technique using image intensity and gradient information. Our method is composed of four steps. First, rays at regular intervals are generated. To minimize the effect of noise, the start and end positions of the ray are calculated. Second, the profiles on each ray are sorted based on the gradient. And priorities are applied to the sorted gradient in the profile. Third, boundary points are extracted by using gradient priority and intensity distribution. Finally, to reduce the error, the extracted boundary points are corrected by using B-spline interpolation. For accuracy evaluation, the average distance differences and overlapping region ratio between results of manual and automatic segmentations are calculated. As the experimental results, the average distance difference error and standard deviation were 1.09mm $\pm0.20mm$. And the overlapping region ratio was 92%.

HI superprofiles of galaxies from THINGS and LITTLE THINGS

  • Kim, Minsu;Oh, Se-Heon
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.68.3-69
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    • 2021
  • We present a novel profile stacking technique based on optimal profile decomposition of a 3D spectral line data cube, and its performance test using the HI data cubes of sample galaxies from HI galaxy surveys, THINGS and LITTLE THINGS. Compared to the previous approach which aligns all the spectra of a cube using their central velocities derived from either moment analysis, single Gaussian or hermite h3 polynomial fitting, the new method makes a profile decomposition of the profiles from which an optimal number of single Gaussian components is derived for each profile. The so-called superprofile which is derived by co-adding all the aligned profiles from which the other Gaussian models are subtracted is found to have weaker wings compared to the ones constructed in a typical manner. This could be due to the reduced number of asymmetric profiles in the new method. A practical test made on the HI data cubes of the THINGS and LITTLE THINGS galaxies shows that our new method can extract more mass of kinematically cold HI components in the galaxies than the previous results. Additionally, we fit a double Gaussian model to the superprofiles whose S/N is boosted, and quantify not only their profile shapes but derive the ratio of the Gaussian model parameters, such as the intensity ratio and velocity dispersion ratio of the narrower and broader Gaussian components. We discuss how the superprofile properties of the sample galaxies are correlated with their other physical properties, including star formation rate, stellar mass, metallicity, and gas mass.

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Measurement of Heat (Mass) Transfer Coefficient on the Blade Surfaces of a Linear Turbine Rotor Cascade With a Four-Axis Naphthalene Profile Measuring System (4-축 나프탈렌 승화깊이 측정시스템을 이용한 터빈 블레이드 표면에서의 열(물질)전달계수 측정)

  • Kwon, Hyun-Goo;Lee, Sang-Woo;Park, Byung-Kyu
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.42-47
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    • 2001
  • The heat (mass) transfer characteristics on the blade surface of a first-stage turbine rotor cascade for power generation has been investigated by employing the naphthalene sublimation technique. A four-axis profile measurement system is successfully developed for the measurements of the local heat (mass) transfer coefficient on the curved blade surface. The experiment is carried out at the free-stream Reynolds number and turbulence intensity of $2.09\times10^5$ and 1.2%. The results on the blade surfaces show that the local heat (mass) transfer on the suction surface is strongly influenced by the endwall vortices, but that on the pressure surface shows a nearly two-dimensional nature. The pressure surface has a more uniform distribution of heat load than the suction one.

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Assessment of the Influence of Application Time of Lidocaine Patch on Pain Intensity after Venipuncture (정맥천자 시 리도카인 패치의 적용시간에 따른 통증경감 효과)

  • No, In Sun;Kim, Se Young
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.25 no.4
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    • pp.250-258
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    • 2018
  • Purpose: This study was done to assess the influence of application time of Lidocaine patch on pain intensity following venipuncture in hospital. Methods: The participants were 31 adult patients admitted to J hospital in G city. Patients' anxiety, blood pressure and pulse were measured when no patch was applied and when a patch was applied. To evaluate the pain intensity and physiological index caused by venipuncture, blood pressure, pulse and pain intensity were checked for patients in the no patch group, and for a 5 minutes of application and 30 minutes application patch. Pain was evaluated using a visual analogue scale, anxiety using the Profile of Mood states developed McNair et al. and modified by Lee. Data were analyzed using one-way repeated measures ANOVA with the SPSS 21.0 program. Results: Anxiety and pain were significantly reduced when a lidocaine patch was applied following venipuncture. There was no significant difference in pain intensity whether the lidocaine patch application is for 30 minutes or application for 5 minutes. Conclusion: Results of this study show that application of lidocaine patch can be used as a nursing intervention for pain reduction by showing that there is no need to wait a long time for pain to be reduced.

Effects of Vowel Differences on Laryngeal DDK (모음에 따른 후두 교호운동 특성)

  • Han, Ji-Yeon;Lee, Ok-Bun
    • MALSORI
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    • v.68
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    • pp.1-15
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    • 2008
  • This study investigated the vowel effect on laryngeal DDK (L-DDK) in terms of rate, regularity, and range. Thirteen normal speakers participated in this experiment. Speakers were asked to repeat the vowels /a, e, i, o, u/ for vocal fold adduction DDK, and /ha, he, hi, ho, hul for vocal fold abduction DDK. Acoustic data was analyzed via Motor Speech Profile. There were 6 parameters: DDKavp and DDKavr for rate of L-DDK, DDKcvp and DDKjit for regulariry of L-DDK, and DDKavi and DDKcvi for range of L-DDK. Results of MANOVA and Fredman analysis showed no significant vowel effect on rate and regularity of L-DDK. MANOVA revealed significant effects of vowels and vocal fold ab/adduction on range of L-DDK. DDK peak intensity (DDKavi) in vowel /i/ production was lower than in vowels /a, e, o, u/. Variation of DDK peak intensity (DDKcvi) was significantly greater for /ha/ than for /a/ production. The implication of these findings on voice and speech pathology is discussed.

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An Experimental Study on Velocity Profiles and Turbulence Intensity of Developing Turbulent Pulsating Flows in the Entrance Region of a Square Duct

  • Park, G.M.;Koh, Y.H.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.4
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    • pp.235-242
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    • 1993
  • The flow characteristics of developing turbulent pulsating flows are investigated experimentally in the entrance region of a square duct ($40mm{\times}40mm$ and 4,000mm). Mean velocity profiles, turbulence intensity and entrance length are measured by using a hot-wire anemometer system together with data acquisition and processing systems. It is found that the velocity waveforms are not changed in the fully developed flow region where that $x/Dh{\geq}40$. For turbulent pulsating flow, the turbulent components in the velocity waveforms increase as the dimensionless transverse position approaches the wall. Mean velocity profiles of the turbulent steady flows follow the one-seventh power law profile in the fully developed flow region. Turbulence intensity increases as the dimensionless transverse position increases from the center to the wall of the duct, and is slightly smaller in the accelerating phase than in the decelerating phase for the turbulent pulsating flows. The entrance length of the turbulent pulsating flow is about 40 times as large as the hydraulic diameter under the present experimental conditions.

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A Study on the Comparison Between Experimental and Numerical Analysis for Developing Turbulent Steady Flows in the Entrance Region of a Square Duct (정4각덕트의 입구영역에서 난류정상유동의 실험해와 수치해의 비교에 관한 연구)

  • 고영하;박길문;봉태근
    • Journal of Advanced Marine Engineering and Technology
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    • v.21 no.3
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    • pp.236-245
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    • 1997
  • The flow characteristics of developing turbulent steady flow are investigated numerically and experimentally in the entrance region of a square duct ($40 mm{\times}40 mm$ and 4, 000 mm). The numerical anaysis are incorporated by finite- volume discretization with staggered grid system and SIMPLE algorithm. The numerical solution are compared with experimental results of mean velocity profiles, turbulence intensity and entrance length. For turbulent steady flow, the turbulent components in the velocity waveforms increase as the dimensionless transverse position approaches the wall. Thrbulence intensity increases as the dimensionless transverse position increases from the center to the wall of the duct for the developing turbulent steady flows. The entrance length of the turbulent steady flow is about 40 times as large as the hydraulic diameter under the present experimental condition.

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Design & Analysis of an Error-reduced Precision Optical Triangulation Probes (오차 최소화된 정밀 광삼각법 프로브의 해석 및 설계)

  • Kim, Kyung-Chan;Oh, Se-Baek;Kim, Jong-Ahn;Kim, Soo-Hyun;Kwak, Yoon-Keun
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.411-414
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    • 2000
  • Optical Triangulation Probes (OTPs) are widely used for their simple structure. high resolution, and long operating range. However, errors originating from speckle, inclination of the object, source power fluctuation, ambient light, and noise of the detector limit their usability. In this paper, we propose new design criteria for an error-reduced OTP. The light source module for the system consists of an incoherent light source and a multimode optical fiber for eliminating speckle and shaping a Gaussian beam Intensity profile. A diffuse-reflective white copy paper, which is attached to the object, makes the light intensity distribution on the change-coupled device(CCD). Since the peak positions of the intensity distribution are not related to the various error sources, a sub-pixel resolution signal processing algorithm that can detect the peak position makes it possible to construct an error-reduced OTP system

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