• Title/Summary/Keyword: Error of L2 study

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The Influence of Assay Error Weight on Gentamicin Pharmacokinetics Using the Bayesian and Nonlinear Least Square Regression Analysis in Appendicitis Patients

  • Jin, Pil-Burm
    • Archives of Pharmacal Research
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    • v.28 no.5
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    • pp.598-603
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    • 2005
  • The purpose of this study was to determine the influence of weight with gentamicin assay error on the Bayesian and nonlinear least squares regression analysis in 12 Korean appen dicitis patients. Gentamicin was administered intravenously over 0.5 h every 8 h. Three specimens were collected at 48 h after the first dose from all patients at the following times, just before regularly scheduled infusion, at 0.5 h and 2 h after the end of 0.5 h infusion. Serum gentamicin levels were analyzed by fluorescence polarization immunoassay technique with TDxFLx. The standard deviation (SD) of the assay over its working range had been determined at the serum gentamicin concentrations of 0, 2, 4, 8, 12, and 16 ${\mu}g$/mL in quadruplicate. The polynominal equation of gentamicin assay error was found to be SD (${\mu}g$/mL) = 0.0246-(0.0495C)+ (0.00203C$^2$). There were differences in the influence of weight with gentamicin assay error on pharmacokinetic parameters of gentamicin using the nonlinear least squares regression analysis but there were no differences on the Bayesian analysis. This polynominal equation can be used to improve the precision of fitting of pharmacokinetic models to optimize the process of model simulation both for population and for individualized pharmacokinetic models. The result would be improved dosage regimens and better, safer care of patients receiving gentamicin.

Fitting a Piecewise-quadratic Polynomial Curve to Points in the Plane (평면상의 점들에 대한 조각적 이차 다항식 곡선 맞추기)

  • Kim, Jae-Hoon
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.1
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    • pp.21-25
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    • 2009
  • In this paper, we study the problem to fit a piecewise-quadratic polynomial curve to points in the plane. The curve consists of quadratic polynomial segments and two points are connected by a segment. But it passes through a subset of points, and for the points not to be passed, the error between the curve and the points is estimated in $L^{\infty}$ metric. We consider two optimization problems for the above problem. One is to reduce the number of segments of the curve, given the allowed error, and the other is to reduce the error between the curve and the points, while the curve has the number of segments less than or equal to the given integer. For the number n of given points, we propose $O(n^2)$ algorithm for the former problem and $O(n^3)$ algorithm for the latter.

Determination of Chemical Composition of Toasted Burley Tobacco by Near Infrared Spectroscopy (근적외선분광법을 이용한 버어리 토스트엽의 화학성분 분석)

  • 김용옥;정한주;백순옥;김기환
    • Journal of the Korean Society of Tobacco Science
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    • v.17 no.2
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    • pp.177-183
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    • 1995
  • This study was conducted to develop the most precise NIR(near infrared spectrometric) calibration for rapid determination of chemical composition in ground samples of toasted burley tobacco using stepwise, stepup, principal component regression(PCR), partial least square(PLS) and modified partial least square(MPLS) calibration method. The number of wavelength(W) selected by stepup multiple linear regression using: second derivative spectra was as follows: total sugar(TS)-4 W, nicotine-9 W, total nitrogen(TN)-2 W, ash-8 W, total volatile base(TVB)-5 W, chlorine4 W, L of color-6 W, a of color-6 W and b of color-7 W. Comparing the calibration equations followed by each chemical components, the most precise calibration equation was MPLS for 75, a and b of color, PLS for nicotine, ash, TVB, chlorine and L of color and stepup for TN. The standard error of calibration(SEC) and standard error of performance(SEP) between result of near infrared analysis and standard laboratory analysis were 0.18, 0.40% for 75, 0.06, 0.08% for nicotine, 0.18, 0.16% for TN, 0.33, 0.46% for ash, 0.04, 0.03% for TVB, 0.08, 0.06% for chlorine, 0.54, 0.58 for L of color, 0.22, 0.22 for a of color and 0.27, 0.27 for b of color, respectively. The SEC and SEP of ash and TVB were within allowable error of standard laboratory analysis, nicotine, TN and chlorine were 1.2-2.0 times and 75 were 2.1-4.0 times larger than allowable error of standard laboratory analysis. The ratio of SEC and SEP to mean were 1.5, 1.6% for L of color, 3.7, 3.8% for a of color and 1.8, 1.8% for b of color, respectively. Key words : burley tobacco chemistry, near infrared spectroscopy.

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Compensation of Initial Position Error and Torque Ripple in Vector Control of Two-phase Hybrid Stepping Motors (2상 하이브리드 스테핑 모터의 벡터 제어 시 초기 각 오차 및 토크 리플 보상)

  • Do-Hyun, Kim;Sang-Hoon, Kim
    • The Transactions of the Korean Institute of Power Electronics
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    • v.27 no.6
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    • pp.481-488
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    • 2022
  • This study proposes compensation methods for the initial position error and torque ripple in vector control of two-phase hybrid stepping motors. Stepping motors have an asymmetrical structure due to misalignment, such as the eccentricity generated by the manufacturing and assembly process. When vector control is applied using the position information measured by an incremental encoder attached to the rotor shaft of such stepping motors, the following problems occur. First, an initial position error occurs during the forced excitation process for the initial rotor position alignment. Second, torque ripple corresponding to the mechanical rotation frequency is generated. In this study, these non-ideal phenomena that occur in vector control of the stepping motor are analyzed, and compensation methods are proposed to eliminate them. The validity of the proposed initial position error and torque ripple compensation methods is verified through experiments on a two-phase hybrid stepping motor drive system.

The Study of Technical Error Analysis on BMD Using DEXA (이중 에너지 X선 흡수 계측법을 이용한 BMD 검사 시 발생할 수 있는 기술적인 오류 분석)

  • Kang, Yeong-Han;Jo, Gwang-Ho
    • Journal of radiological science and technology
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    • v.29 no.4
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    • pp.229-236
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    • 2006
  • Purpose: This study was conducted to search for the type of technical error in DEXA(dual-energy X-ray absorptiometry) and the effect of error to measurement of BMD. Materials and Methods: The changes of BMD($g/cm^2$, T-score) by patients information(Age, Weight, Height, Manopause age) input error and Confirming ROI error were investigated. Using spine phantom, we canned 10 times by age(5, 10), weight(10, 20 kg), height(5, 10 cm), manopause age(5, 10) increase & decrease respectively. Scanning region(L-spine, femur, Forearm) of 10 patients was calculated by changing ROI respectively. Analysis of difference for mean(precision 1%) were carried out. Results: The error of patient information(Age, Weight, Height, Manopause age) was not changed differently. In confirming ROI, the BMD and T-score of L-spine involving T-12 was decreased to $0.063\;g/cm^2$, 0.3 and involving L-5 increased to $0.077\;g/cm^2$, 0.5. In narrowing 1 cm of vertical line of ROI, the BMD and T-score decreased to $0.006\;g/cm^2$, 0.1 and in 2 cm, $0.021\;g/cm^2$, 0.15, each. In hip ROI, Upper and left shift(0.5 cm) of line was not influenced BMD and T-score. In 0.5 cm lower shift(lesser trochanter below), the BMD and T-score increased $0.031\;g/cm^2$, 0.3 and in 1 cm $0.094\;g/cm^2$, 0.65, each. In forearm ROI, the BMD and T-score decreased $0.042\;g/cm^2$, 0.9 involving 1 cm lower wrist. And expanding 1 cm of vertical line, the BMD and T-score decreased $0.008\;g/cm^2$, 0.1 and in 2 cm, $0.021\;g/cm^2$, 0.3, each. The L-spine, hip, forearm ROI error was changed differently. Conclusion: There are so many kinds of technical error in BMD processing. Errors according to age, weight, height, manopause age did not influent to $BMD(g/cm^2)$ and T-score. There are mean differences BMD and T-score in confirming ROI. For the precision exam, in L-spine processing, L1-4 have to confirmed without shift of ROI vertical line. In hip processing, the ROI have to included greater trochanter, femur head and lesser trochanter. In forearm processing, the ROI have to included wrist, radius and ulnar.

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A Study of STS 316L Threaded Elbow Fitting Fabrication by Metal Injection Molding (금속사출성형을 이용한 STS 316L 밸브피팅 제작에 대한 연구)

  • Kim, J.Y.;Kim, S.J.;Chung, S.T.;Ahn, S.
    • Transactions of Materials Processing
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    • v.24 no.2
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    • pp.121-129
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    • 2015
  • A net-shape forming of small and complex-shaped metal parts by metal injection molding (MIM) has economic advantages in mass production, especially for STS 316L valve fitting. STS 316L offers excellent corrosion resistance, but it has poor machinability, which is a limitation in using it for a cost-effective production where both forging and machining are employed. Simulation and experimental analysis were performed to develop a MIM STS 316L 90° elbow fitting minimizing trial and error. A Taguchi method was used to determine which input parameter was the most sensitive to possible defects (e.g. sink mark depth) during the injection molding. The final prototype was successfully built. The results indicate that the simulation tool can be used during the design process to minimize trial and error, but the final adjustment of parameters based on field experience is essential.

Effect of the Weight in Precise Levelling Net (중량값이 정밀수준망에 미치는 영향)

  • 이석찬;조규전;최병길
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.7 no.1
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    • pp.11-18
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    • 1989
  • Observations to precise levelling nets contain different types of error because it has been caried out with various instruments and techniques, and also completed through long period. In order to establish a precise levelling nets, therefore, the weight function has to be selected adequately in the adjustment of nets. The purpose of the study is to determine a suitable weight function for the first order geodetic levelling nets in Korea and, therefore, the various numerical tests are performed with different statistical error models. The result of the study shows that the weight function, W=1/$L^2$ is more efficient than W=1/L in the first order levelling nets in the Korea.

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Fundamental Investigation of Non-invasive Determination of Glucose by Near Infrared Spectrophotometry (근적외선 분광법을 이용한 비침투적 혈당 분석법 개발에 관한 기초 연구)

  • Kim, Hyo J.;Woo, Young A.;Chang, Soo H.;Cho, Chang H.;Cantrell, Kevin;Piepmeier, Edward H.
    • Analytical Science and Technology
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    • v.11 no.1
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    • pp.47-53
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    • 1998
  • This study is to improve the diagnosis of diabetes mellitus and the self-monitoring of blood glucose in people with diabetes by providing a non-invasive method of monitoring blood glucose. A near-infrared (NIR) spectrophotometer was used to measure absorption spectra of 80 glucose samples ranges from 1 mg/dL to 200 mg/dL, and shows the standard error of prediction 1.8 mg/dL. Also, to investigate the effect of interference in blood, NaCl and sand were added in glucose and found the standard error of prediction of 2.8 mg/dL and 3.8 mg/dL, respectively. A new and more accurate calibration system for the spectrophotometer was developed from systematic study of light scattering, which cause nonlinear spectrophotometer response.

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An Electropalatographic Study of English 1, r and the Korean Liquid Sound ㄹ

  • Ahn, Soo-Woong
    • Speech Sciences
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    • v.8 no.2
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    • pp.93-106
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    • 2001
  • The pronunciation of English l and r was a consistent problem in learning English in Korea as well as Japan. This problem occurs from the fact that in Korea and Japan there is only one liquid sound. Substituting the Korean liquid for English l and r was a common error. The pronunciation of the dark l causes a further problem in pronouncing the English l sound. To see the relationship between the English l, r, and the Korean liquid sound, an electropalatographic (EPG) experiment was done. The findings were (1) there were no tongue contacts either on the alveolar ridge or on the palate during the articulation of the dark l. (2) The Korean liquid sound was different in the tongue contact points either from English l or r. The English clear l consistently touched the alveolar ridge in the forty tokens, but the Korean liquid sound in the intervocalic and word-final position touched mainly the alveopalatal area. The English r touched exclusively the velum area. The Korean intervocalic /l/ was similar to English flap in EPG and spectrographic data. There was evidence that the word-final Korean /l/ is a lateral.

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A Study of Six Sigma and Total Error Allowable in Chematology Laboratory (6 시그마와 총 오차 허용범위의 개발에 대한 연구)

  • Chang, Sang-Wu;Kim, Nam-Yong;Choi, Ho-Sung;Kim, Yong-Whan;Chu, Kyung-Bok;Jung, Hae-Jin;Park, Byong-Ok
    • Korean Journal of Clinical Laboratory Science
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    • v.37 no.2
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    • pp.65-70
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    • 2005
  • Those specifications of the CLIA analytical tolerance limits are consistent with the performance goals in Six Sigma Quality Management. Six sigma analysis determines performance quality from bias and precision statistics. It also shows if the method meets the criteria for the six sigma performance. Performance standards calculates allowable total error from several different criteria. Six sigma means six standard deviations from the target value or mean value and about 3.4 failures per million opportunities for failure. Sigma Quality Level is an indicator of process centering and process variation total error allowable. Tolerance specification is replaced by a Total Error specification, which is a common form of a quality specification for a laboratory test. The CLIA criteria for acceptable performance in proficiency testing events are given in the form of an allowable total error, TEa. Thus there is a published list of TEa specifications for regulated analytes. In terms of TEa, Six Sigma Quality Management sets a precision goal of TEa/6 and an accuracy goal of 1.5 (TEa/6). This concept is based on the proficiency testing specification of target value +/-3s, TEa from reference intervals, biological variation, and peer group median mean surveys. We have found rules to calculate as a fraction of a reference interval and peer group median mean surveys. We studied to develop total error allowable from peer group survey results and CLIA 88 rules in US on 19 items TP, ALB, T.B, ALP, AST, ALT, CL, LD, K, Na, CRE, BUN, T.C, GLU, GGT, CA, phosphorus, UA, TG tests in chematology were follows. Sigma level versus TEa from peer group median mean CV of each item by group mean were assessed by process performance, fitting within six sigma tolerance limits were TP ($6.1{\delta}$/9.3%), ALB ($6.9{\delta}$/11.3%), T.B ($3.4{\delta}$/25.6%), ALP ($6.8{\delta}$/31.5%), AST ($4.5{\delta}$/16.8%), ALT ($1.6{\delta}$/19.3%), CL ($4.6{\delta}$/8.4%), LD ($11.5{\delta}$/20.07%), K ($2.5{\delta}$/0.39mmol/L), Na ($3.6{\delta}$/6.87mmol/L), CRE ($9.9{\delta}$/21.8%), BUN ($4.3{\delta}$/13.3%), UA ($5.9{\delta}$/11.5%), T.C ($2.2{\delta}$/10.7%), GLU ($4.8{\delta}$/10.2%), GGT ($7.5{\delta}$/27.3%), CA ($5.5{\delta}$/0.87mmol/L), IP ($8.5{\delta}$/13.17%), TG ($9.6{\delta}$/17.7%). Peer group survey median CV in Korean External Assessment greater than CLIA criteria were CL (8.45%/5%), BUN (13.3%/9%), CRE (21.8%/15%), T.B (25.6%/20%), and Na (6.87mmol/L/4mmol/L). Peer group survey median CV less than it were as TP (9.3%/10%), AST (16.8%/20%), ALT (19.3%/20%), K (0.39mmol/L/0.5mmol/L), UA (11.5%/17%), Ca (0.87mg/dL1mg/L), TG (17.7%/25%). TEa in 17 items were same one in 14 items with 82.35%. We found out the truth on increasing sigma level due to increased total error allowable, and were sure that the goal of setting total error allowable would affect the evaluation of sigma metrics in the process, if sustaining the same process.

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