• Title/Summary/Keyword: true values

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Determination of elastic parameters of the deformable solid bodies with respect to the Earth model

  • Guliyev, Hatam H.;Javanshir, Rashid J.;Hasanova, Gular H.
    • Geomechanics and Engineering
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    • v.15 no.5
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    • pp.1071-1080
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    • 2018
  • The study of behavior and values of deformations in the geological medium makes the scientific basis of the methodology of synthesis of true values of parameters of its physico-mechanical and density properties taking into account the influence of geodynamic impacts. The segments of continuous variation of homogeneous elastic uniform deformations are determined under overall compression of the medium. The limits of these segments are defined according to the criteria of instability (on geometric form changes and on "internal" instability). Analytical formulae are obtained to calculate current and limiting (critical) values of deformations within the framework of various variants of small and large initial deformations of the non-classically linearized approach of non-linear elastodynamics. The distribution of deformation becomes non-uniform in the medium while the limiting values of deformations are achieved. The proposed analytical formulae are applicable only within homogeneous distribution of deformations. Numerical experiments are carried out for various elastic potentials. It is found that various forms of instability can precede phase transitions and destruction. The influence of these deformation phenomena should be removed while the physico-mechanical and density parameters of the deformed media are determined. In particular, it is necessary to use the formulae proposed in this paper for this purpose.

Estimation of Hydrodynamic Coefficients for an AUV Using Nonlinear Observers (비선형 관측기를 이용한 무인잠수정의 유체동역학 계수 추정)

  • Kim, Joon-Young
    • Journal of Ocean Engineering and Technology
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    • v.20 no.6 s.73
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    • pp.24-34
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    • 2006
  • Hydrodynamic coefficients strongly affect the dynamic performance of an AUV. Thus, it is important to know the true values of these coefficients, in order to accurately simulate the AUV's dynamic performance. Although these coefficients are generally obtained experimentally, such as through the PMM test, the measured values are not completely reliable because of experimental difficulties and errors. Another approach, by which these coefficients can be obtained, is the observer method, in which a model-based estimation algorithm estimates the coefficients. In this paper, the hydrodynamic coefficients are estimated using two nonlinear observers: a sliding mode observer and an extended Kalman filter. Their performances are evaluated in Matlab simulations, by comparing the estimated coefficients obtained from the two observer methods, with the experimental values as determined from the PMM test. A sliding mode controller is constructed for the diving and steering maneuver by using the estimated coefficients. It is demonstrated that the controller, applied with the estimated values, maintains the desired depth and path with sufficient accuracy.

Superconducting Tunnel Junction Detectors for Mass Spectrometry

  • Ohkubo, M.;Zen, N.;Kitazume, T.;Ukibe, M.;Shiki, S.;Koike, M.
    • Progress in Superconductivity
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    • v.14 no.2
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    • pp.77-81
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    • 2012
  • With conventional mass spectrometry (MS), ions are separated according to mass/charge (m/z) ratios. We must speculate the z values to obtain the m values. Superconducting tunnel junction (STJ) detectors can solve this problem, and true mass spectrometry becomes possible instead of m/z spectrometry. The STJ detectors were installed in MS instruments with a variety of ion sources. As an example, we report fragmentation analysis of a non-covalent protein complex of hemoglobin.

A Study on TRANSYT Model-embedded Parameters (TRANSYT 모델의 내재 모개변수에 관한 연구)

  • 도철웅
    • Journal of Korean Society of Transportation
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    • v.6 no.1
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    • pp.55-64
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    • 1988
  • Prior to using any computer model, the program-embedded palameters showing significant differences from real world should be calibrated. This is especially true when the model is expected to be used fro various roadway and traffic condition. The calibration of TRANSYT model was conducted for the parameters of start-up delay, and lag, stop penalty(K), platoon dispersion factor, and saturation flow rate. The values of the parameters were obtained by theoretical methods from actual field measurements for discharging and arrival pattern. The sites elected for the study was an intersection of Dongil-Ro and Hwarang-Ro, and a 334 meter downstrean section from the intersection stop line on westbound Hwarang-Ro. The study results showed that the start-up delay was 2.6 sec, end lag was 1.0 sec, saturation flow rate was 2287 pcphgpl, platoon dispersion factor was 0.2-03, and stop penalty(K) was 32. However, since these parameters re apt to depend on traffic and roadway condition, it is doubtful whether the obtained values will be applicable to the area-wide situation other than this particular site.

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Measurement of Springback Ratio Using a Bend Rig (개선된 굽힘 시험장치를 이용한 스프링백 비의 측정)

  • 김용우;공성일;남진영
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.410-415
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    • 2002
  • A winding bend rig is designed to overcome the drawbacks of the conventional bend rig for measuring springback ratio of a strip or plate. Using the present bend rig, springback ratios are measured and they are compared with ones that obtained by using simple beam theory and tensile test. Theoretically, there should be no difference between the two values as far as the simple beam theory holds true for the bending test. But, within the scope of our tests, there is a difference of 5% between the two values since the specimen under bend test is subjected to a transverse shear force and friction force on the surface of the specimen.

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Chemical Compositions and Biological Feeding Values of Spirutina platensis Grown at Swine-Waste Effluent (돈분폐액 배양 Spirulina platensis의 화학적 조성 및 생물학적 사료가치)

  • 오상집;정연종;이준엽;이현용
    • Korean Journal of Poultry Science
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    • v.22 no.3
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    • pp.155-160
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    • 1995
  • To evaluate the nutritive values of outdoor mass cultivated Spirulina platensis both chemical analysis and bioassay were carried out using adult cockerels. Blue-green algae, Spirulina platensis contained about 71g /l00g DM of crude protein with balanced amino acid profiles although methionine is liable to he limiting to animals. Compared to fish meal, calcium content and calcium : phosphorus ratio of the Spirulina were not suitable in terms of animal requirements. Reasonable amount of y-linolenic acid(C18: 3 $\omega$6) in Spirulina platensis draws a clinical attention due to its historically recognized pharmacotheraputic functions. Metabolizable energy contents of Spirulina were 3.67 and 3.11 mcal /kg DM for TMEn and AMFn, respectively, which therefore, can he a reliable energy source for poultry. True amino acid availabilities of essential amino acids of Spirulina platensis were higher than 90% for poultry, which is better than comparative ingredient like fish meal. Overall data from both chemical analysis and bioassay demonstrated that the Spirulina platensis could he a favorable protein feedstuffs for poultry.

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Discriminant Analysis under a Patterned Missing Values

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
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    • v.18 no.1
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    • pp.13-25
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    • 1989
  • This paper suggests a classification rule with unequal covariance matrices when a patterned incomplete data are involved in the discriminant analysis. This is an extension of Geisser's (1966) result to the case of missing observations. For the calssificaiton rule, we introduce an algorithm which contains data augmentation step and Monte Carlo integration step and show that the algorithm yields a consistant estimator of true classification probability. The proposed method is compared to the complete observation vector method through a Monte Carlo study. The results show that the suggested method, in general, performs better than the complete observation vector method which ignores those vectors of observation with one or more missing values from the analysis. The results also verify the consistency of the algorithm.

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Optimization of parameters in segmentation of large-scale spatial data sets (대용량 공간 자료들의 세그먼테이션에서의 모수들의 최적화)

  • Oh, Mi-Ra;Lee, Hyun-Ju
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.897-898
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    • 2008
  • Array comparative genomic hybridization (aCGH) has been used to detect chromosomal regions of amplifications or deletions, which allows identification of new cancer related genes. As aCGH, a large-scale spatial data, contains significant amount of noises in its raw data, it has been an important research issue to segment genomic DNA regions to detect its true underlying copy number aberrations (CNAs). In this study, we focus on applying a segmentation method to multiple data sets. We compare two different threshold values for analyzing aCGH data with CBS method [1]. The proposed threshold values are p-value or $Q{\pm}1.5IQR$ and $Q{\pm}1.5IQR$.

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The Analytical Bias of Total Hydrocarbon (THC) Measurements in Relation to the Selection of Standard Gas Compound (총탄화수소의 계측에서 표준시료성분의 선택에 따른 오차 발생 연구)

  • Kim, Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.4
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    • pp.449-452
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    • 2010
  • In this article, the performance of the THC analyzer was inspected using two different span gases of methane ($CH_4$) and propane ($C_3H_8$). To explore the effect of standard gas selection, MicroFID system was tested by the following procedures. Initially, the system is spanned by propane gas of 60 ppm (or 180 ppmC). The system is then run against methane standards prepared at 5 different concentrations of 200, 250, 300, 400, and 500 ppm. According to the suggestion of the KMOE's test procedure to use multiplying a factor of 3 (for propane), the resulting THC values derived by methane standards were systematically biased with ~500% error relative to true value. This paper discusses the interpretation procedures to obtain the least biased THC values for a given span set-up.

Robust inference with order constraint in microarray study

  • Kang, Joonsung
    • Communications for Statistical Applications and Methods
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    • v.25 no.5
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    • pp.559-568
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    • 2018
  • Gene classification can involve complex order-restricted inference. Examining gene expression pattern across groups with order-restriction makes standard statistical inference ineffective and thus, requires different methods. For this problem, Roy's union-intersection principle has some merit. The M-estimator adjusting for outlier arrays in a microarray study produces a robust test statistic with distribution-insensitive clustering of genes. The M-estimator in conjunction with a union-intersection principle provides a nonstandard robust procedure. By exact permutation distribution theory, a conditionally distribution-free test based on the proposed test statistic generates corresponding p-values in a small sample size setup. We apply a false discovery rate (FDR) as a multiple testing procedure to p-values in simulated data and real microarray data. FDR procedure for proposed test statistics controls the FDR at all levels of ${\alpha}$ and ${\pi}_0$ (the proportion of true null); however, the FDR procedure for test statistics based upon normal theory (ANOVA) fails to control FDR.