• Title/Summary/Keyword: Saturation curve

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A Multicenter Pilot Study of Biliary Atresia Screening Using Digital Stool Color Imaging

  • Kannamon Waitayagitgumjon;Wannisa Poocharoen;Suchin Trirongjitmoah;Kriengsak Treeprapin;Arada Suttiwongsing;Thetiya Wirifai;Chira Trirongchitmoh;Pitiporn Tangkabuanbutr
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.27 no.3
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    • pp.168-175
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    • 2024
  • Purpose: The presence of alcoholic stool in biliary atresia (BA) patients is the basis of a stool color card (SCC), a screening tool that has led to more patients receiving Kasai portoenterostomy earlier. This study aimed to evaluate the color image processing of stool images captured using smartphones. We propose that measuring digital color parameters is a more objective method for identifying BA stools and may improve the sensitivity of BA screening. Methods: A prospective study was conducted in five hospitals in Thailand between October 1, 2020, and December 31, 2021. Stools from infants presenting with jaundice, acholic stool, or dark-colored urine were photographed. Digital image color analysis was performed, and software was developed based on the color on the original SCC. Sensitivity and specificity for predicting BA stools were compared between the SCC and the software. Results: Of 33 infants eligible for data collection, 19 were diagnosed with BA. Saturation and blue were two potential digital color parameters used to differentiate BA stools. The receiver operating characteristic curve was used to determine the optimum cutoff point of both values, and when saturation ≤56 or blue ≥61 was set as a threshold for detecting BA stool, high accuracy was achieved at 81.8% and 78.8%, respectively. Conclusion: Digital image processing is a promising technology. With appropriate cutoff values of saturation in hue, saturation, value and blue in red, green, blue color models, BA stools can be identified, and equivocal-colored stools of non-BA patients can be differentiated with acceptable accuracy in infants presenting with jaundice.

An approach for the pH control (pH적정공정의 적응제어에 관한 연구)

  • 김호동;장홍래;이재설;박현수
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.337-342
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    • 1989
  • The control of a pH value in radwaste treatment process is difficult due to the nonlinearity of the titration curve and its strong sensivity to disturbances. This paper describes an adaptive control strategy which is model-based and allows for direct use of available measurements. This algorithm forces the nonlinear process to follow a desired linear system trajectory, and were applied to the control of a simulated pilot-scale pH process. The simulation study showed that it has the potential advantage over the transformation methods that control effort saturation can be accomodated readily.

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Determination of Operating frequency its Design of the Self-exited electronic Ballast (자려식 전자안정기의 동작 주파수 결정과 설계)

  • 박종연;전경준;한재현
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.315-318
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    • 2002
  • In this paper, we have studied about the determination methode of the operating frequency, and the design technique for the self-exited electronic ballast. Because we use the saturation characteristics of the ferrite core, the variation of the B/H curve characteristics for the selected core in the most important factor for the stabilization. Although it is impossible to fix the operation frequency, the self-exited electronic ballast is widely used because of its cost and the simplicity of its structure.

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Determination of the Distribution of the Preisach Density Function With Optimization Algorithm

  • Hong Sun-Ki;Koh Chang Seop
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.5B no.3
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    • pp.258-261
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    • 2005
  • The Preisach model needs a distribution function or Everett function to simulate the hysteresis phenomena. To obtain these functions, many experimental data obtained from the first order transition curves are usually required. In this paper, a simple procedure to determine the Preisach density function using the Gaussian distribution function and genetic algorithm is proposed. The Preisach density function for the interaction field axis is known to have Gaussian distribution. To determine the density and distribution, genetic algorithm is adopted to decide the Gaussian parameters. With this method, just basic data like the initial magnetization curve or saturation curves are enough to get the agreeable density function. The results are compared with experimental data and we got good agreements comparing the simulation results with the experiment ones.

Characteristics and Prediction of Shear Strength for Unsaturated Residual Soil (풍화잔적토의 불포화전단강도 예측 및 특성연구)

  • 이인모;성상규;양일순
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.377-384
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    • 2000
  • The characteristics and prediction model of the shear strength for unsaturated residual soils was studied. In order to investigate the influence of the initial water content on the shear strength, unsaturated triaxial tests were carried out varying the initial water content, and the applicability of existing prediction models for the unsaturated shear strength was testified. It was shown that the soil - water characteristic curve and the shear strength of the unsaturated soil varied with the change of the initial water content. A sample compacted in the lower initial water content needs a higher suction to get the same degree of saturation while the shear strength of a sample with the lower initial water content displays a lower value. In order to apply the existing prediction models of the unsaturated shear strength to granite residual soils, a correction coefficient, α, on the internal friction angle, ø'was added.

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The Refractive Index Change for Tinted Time of CR-39 Lens (CR-39 렌즈 착색시간에 따른 굴절률(n) 변화)

  • Kim, Yong Geun
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.151-155
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    • 2000
  • We calculated a refractive index of the lens surface by measuring a spectral reflectance for a tinted time on manufacturing of the color lens. The longer a tinted time, the larger a reflectance and reflective index. The refractive index increased for a time up to the colorant's saturation state on the lens surface. The refractive index's change curve of blue color lens for a time depended on the Boltzmann growth curve. then we obtained the parameter's values of $n_{min}=1.482$, $n_{max}=1.497$, $t_c=11.53$ and $d_0=2.287$.

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Evaluation of Thermal Embrittlement for Cast Austenitic Stainless Steel Piping in PWR Nuclear Power Plants (PWR 원전 주조 스테인리스강 배관의 열취화 평가)

  • Kim, Cheol;Jin, Tae-Eun
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.96-101
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    • 2004
  • Cast austenitic stainless steel is used for several components, such as primary coolant piping, elbow, pump casing and valve bodies in light water reactors. These components are subject to thermal embrittlement at the reactor operating temperature. The objective of this study is to summarize the method of estimating ferrite content, Charpy impact energy and J-R curve and to evaluate the thermal embrittlement of the cast austenitic stainless steel piping used in the domestic nuclear power plants. The result of evaluation, two domestic nuclear power plants used CF-8M and CF-8A material has adequate fracture toughness after saturation.

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The frequency and magnetic characteristics of YIG with the variation of $Al_2O_3$ additions ($Al_2O_3$조성변화에 따른 YIG의 주파수 및 자기특성)

  • 홍기원;김명호;장경욱;이준웅
    • Electrical & Electronic Materials
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    • v.8 no.6
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    • pp.787-794
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    • 1995
  • To improvement the magnetic and frequency properties of YIG(Yttrium-Iron Garnet) in microwave region, it is investigated that the effect of $Al^{3+}$ ions on magnetic and frequency characteristics of YIG, using samples of basic YIG composition( $Y_{3}$F $e_{5}$ $O_{l2}$) added with A1$_{2}$ $O_{3}$ from 0 to 2.5 [mol%]. The measurment is conducted mainly for the structural properties and magnetical properties. The structural properties is measured using SEM(Scanning Electro Microscope), EDX(Energy-dispersive X-ray spectrometer) and XRD(X-ray diffraction equipment). The magnetical properties is measured with B-H curve tracer and impedance analyzer. As a result, it is confin-ned that the effect of eddy current loss is minimized while maintaining high saturation flux density of YIG, when YIG is added with 0.5 [mol%] of A1$_{2}$ $O_{3}$.>.>.

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Curve- Fitting Program for Reaction Progress Curves (Curve-Fitting Program을 이용한 반응진행곡선의 예측에 관한연구)

  • 홍정화;최진호;변대석
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.19 no.3
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    • pp.215-218
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    • 1990
  • Saturation growth model was evaluated to predict the formation of product as a function of time. Good agreement was observed with homogenous and heterogenous reactions, Prediction of product yield can be made reasonably using this model. In addition accuracy of measured values can be roughly evaluated by this model. User-friendly computer program in BASIC was written to evaluate the constants Pmax and K as well as averages of relative errors.

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Flux Linkage Estimation in a Switched Reluctance Motor Using a Simple Reluctance Circuit

  • Lee, Cheewoo
    • Journal of Magnetics
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    • v.18 no.1
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    • pp.57-64
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    • 2013
  • Flux linkage of phase windings is a key parameter in determining the behavior of a switched reluctance motor (SRM) [1-8]. Therefore, the accurate prediction of flux linkage at aligned and unaligned rotor positions makes a significant contribution to the design of an SRM and its analytical approach is not straightforward due to nonlinear saturation in flux. Although several different approaches using a finite element analysis (FEA) or a curve-fitting tool have been employed to compute phase flux linkage [2-5], they are not suitable for a simple design procedure because the FEA necessitates a large amount of time in both modeling and solving with complexity for every motor design, and the curve-fitting requires the data of flux linkage from either an experimental test or an FEA simulation. In this paper, phase flux linkage at aligned and unaligned rotor positions is estimated by means of a reluctance network, and the proposed approach is analytically verified in terms of accuracy compared to FEA.