• Title/Summary/Keyword: Comparison Test

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Statistical Test of Agreement between Measurements in Method-comparison Study (검사법의 일치도 평가를 위한 분석기법)

  • Pak, Son-Il;Oh, Tae-Ho
    • Journal of Veterinary Clinics
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    • v.28 no.1
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    • pp.108-112
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    • 2011
  • In clinical settings, researchers often want to assess agreement between two measurements (or tests) of the same continuous variable. For example, when new point-of-care analyzer for testing blood glucose level were introduced clinicians need to compare results from standard or established laboratory method of measurement to those of new or point-of-care analyzer. The question in a method-comparison study would either of two different methods be used to measure the same variable equivalently. In this paper common misuse of statistical methodologies seen in the medical literatures such as correlation coefficient and paired t-test are discussed. The Bland-Altman technique has been widely used for this purpose and provides a graphic in presentation of the findings from a method-comparison study, with a mean value of measurement, this bias and the limits of agreement. For ease of application and interpretation of this technique we discussed the analysis procedure and illustrated with two worked examples. Finally, a number of alternative ways in which data can be analysed and reported in such studies were reviewed.

A Clinical Study of Sleep According to Sasang Constitution (사상체질에 따른 수면의 특징에 대한 연구)

  • Park, Seong-Sik;Choi, Jeong-Rak
    • Journal of Sasang Constitutional Medicine
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    • v.15 no.3
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    • pp.204-215
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    • 2003
  • Objectives : This paper was for studying the features of sleep according to Sasang Constitution and to be helpful to make a diagnosis Sasang Constitution. Using the result of this study, it will be helpful to diagnose a Sasang constitution. Methods : There were 610 patients(258 men, 352 women) who answered questionnaire and were diagnosed by the Sasang Constitution Specialist at Constitutional Clinic of Dongguk Bundang Oriental Hospital. Using the response of questionnaire and several statistical techniques such as homogeneity test and multiple comparison, we tried to find the characteristics of each constitution depending on its sleep behaviors. 3. Results : As a result of the analysis of questionnaire, Soeumin has many dreams in comparison with other constitution(p<0.01). Taeumin and Soyangin have a few dream in comparison with Soeumin(p<0.01). Taeyangin has a characteristic that 'he is not drowsy comparatively, he awakes easily, he is not drowsy if it is cold, he is not drowsy and has many dreams if he has many stress.(p<0.01) Taeumin has a characteristics that 'he has a few dream in ordinary times'(p<0.01).

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Effect of an Agreement on Means to Achieve Smoking Cessation Goals among College Student Smokers (흡연 대학생의 목표달성방법 합의가 금연목표달성에 미치는 효과)

  • Choi In-Hee
    • Journal of Korean Academy of Nursing
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    • v.35 no.7
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    • pp.1362-1370
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    • 2005
  • Purpose: The purpose of this study was to identify the degree of attaining a smoking cessation goal when an agreement on means to achieve smoking cessation among male college student smokers was established. Method: This study was planned as a nonequivalent control group non-synchronized design and the sample was divided into an agreement group and a comparison group by convenience sampling in a college of G city. The data was analysed with SPSS Win10.0 using a Likelihood $x^2-test$, Odds ratio, Paired t-test and ANCOVA. Result: The theory that the degree of smoking cessation will be higher in the agreement group than the Comparison group was rejected (${\delta}$ = 2.567, p = .055). The theory that nicotine dependency will be lower in the agreement group than the comparison group was supported (F = 3.965, P = .049); however, the theory that the number of cigarettes smoked per day will be lower in the agreement group than the comparison group was rejected (F = 1.342, p = .252). Conclusion: It has been shown that an agreement on means to achieve smoking cessation goals is a key factor to success in quitting smoking.

Evaluation and Comparison of the Solubility Models for Solute in Monosolvents

  • Min-jie Zhi;Wan-feng Chen;Yang-bo Xi
    • Korean Chemical Engineering Research
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    • v.62 no.1
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    • pp.53-69
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    • 2024
  • The solubility of Cloxacillin sodium in ethanol, 1-propanol, isopropanol, and acetone solutions was measured at different temperatures. The melting property was also tested by using a differential scanning calorimeter (DSC). Then, the solubility data were fitted using Apelblat equation and λh equation, respectively. The Wilson model and NRTL model were not utilized to correlate the test data, since Cloxacillin sodium will decompose directly after melting. For comparison purposes, the four empirical models, i.e., Apelblat equation, λh equation, Wilson model and NRTL Model, were evaluated by using 1155 solubility curves of 103 solutes tested under different monosolvents and temperatures. The comparison results indicate that the Apelblat equation is superior to the others. Furthermore, a new method (named the calculation method) for determining the Apelblat equation using only three data points was proposed to solve the problem that there may not be enough solute in the determination of solubility. The log-logistic distribution function was used to further capture the trend of the correlation and to make better quantitative comparison between predicted data and the experimental ones for the Apelblat equation determined by different methods (fitting method or calculation method). It is found that the proposed calculation method not only greatly reduces the number of test data points, but also has satisfactory prediction accuracy.

Finite Element Modeling of Low Density Polyurethane Foam Material (저밀도 폴리우레탄 포옴재료의 유한요소 모델링)

  • 김원택;최형연
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.2
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    • pp.183-188
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    • 1996
  • The compressive stress-strain response of Low Density Polyurethane foam material is modeled using the finite element method. A constitutive equation which include experimental constants based on quasi-static and dynamic uniaxial compression test is proposed. Impact test with different impactor masses and velocities are performed to verify the proposed model. The comparison between impact test and finite element analysis shows good agreements.

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Aerodynamic Analysis of Tilt-Rotor Unmanned Aerial Vehicle with Computational Fluid Dynamics

  • Kim Cheol-Wan;Chung Jin-Deog
    • Journal of Mechanical Science and Technology
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    • v.20 no.4
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    • pp.561-568
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    • 2006
  • CFD simulation for one of tilt-rotor UAV configurations, TR-E2S1, was performed to investigate its aerodynamic characteristics. Control surfaces such as elevator and rudder were deflected and wing incidence angle was changed. Also aerodynamic stabilities were analyzed with the variation of pitch and yaw angles. The comparison of CFD with wind tunnel test results reveals the same trends in the aerodynamic characteristics and stabilities. However 12% scale wind tunnel test model is too small for accurate data collection and should build a high fidelity model for quantitative data comparison.

A Study on Strength of shear Connectors in Composite Beams of Steel and Lightweight Concrete Slabs with Deck Plate (덱크플레이트를 사용한 경량콘크리트 슬래브와 철골보의 합성보에서 쉬어코넥터의 내력에 관한 연구)

  • 김종식;박성무
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.293-298
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    • 1995
  • The strength of shear connectors embedded in lightweight concrete slab with deck plate is influenced by various factors of deck plate, shear conncetor and concrete. Generally, it is reported that the strength of shear connector in lightweight concrete decreases in comparison with that in normal concrete. So this paper is to use compressive strength of lilghtweight concrete, width-height ratio of deck plate, and cross sectional area of shear conncetor as variables, to evaluate the strength of shear conncetors in composite beam of steel and lilghtweight concrete slabs with deck plate, and then to suggest the reasonable strength equation by comparing the push-out test results with establixhed strength formula. As the result of 24 specimens test, in case of lightweight concrete slab with deck plate, it has showed that in the same strength, the strength of shear connector decreased about 10~20% in comparison with that in normal concrete. In spite of lightweight concrete, the test results were closely approached the established strength formula of shear connector using Fisher's reduction coefficient.

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Development and Implementation of Elementary Mathematics Curriculum (창의적 문제해결력 중심의 수학 교육과정 개발 및 적용: 초등학교 수준을 중심으로)

  • 김정효;권오남
    • Education of Primary School Mathematics
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    • v.4 no.2
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    • pp.83-103
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    • 2000
  • The purpose of this study is to develop and implement an alternative elementary mathematics curriculum to enhance creative problem solving ability. The curriculum consisting of three main elements was developed. The three elements are content knowledge, process knowledge and creative thinking skills. The curriculum contents and the units were developed by mathematics educators, elementary educators, psychologists, elementary school teachers and curriculum specialists for 3 years. In order to test the effectiveness of the developed curriculum, the 5 units based on a problem-based-learning (PBL) method were implemented in a 5th grade class as an experimental group during the second semester. For the comparison group the ordinary lesson based on the 6th national mathematics curriculum was implemented during the same period. Performance assessment was developed and used for the pre and post test. T-est was use to testify that the effect of the curriculum is statistically signigicant. The results of the test showed that the experimental group progressed significantly in the creative problem solving ability, but the comparison group did not.

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Image Comparison Using Directional Expansion Operation

  • Yoo, Suk Won
    • International Journal of Advanced Culture Technology
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    • v.6 no.3
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    • pp.173-177
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    • 2018
  • Masks are generated by adding different fonts of learning data characters in pixel unit, and pixel values belonging to each of the masks are divided into 3 groups. Using the directional expansion operators, we expand the text area of the test data character into 4 diagonal directions in order to create the boundary areas to distinguish it from the background area. A mask with a minimum average discordance is selected as the final recognition result by calculating the degree of discordance between the expanded test data and the masks. Image comparison using directional expansion operations more accurately recognizes test data through 4 subdivided recognition processes. It is also possible to expand the ranges of 3 groups of pixel values of masks more evenly such that new fonts can easily be added to the given learning data.

A Comparison of the Direct Shear Test and Shear Simulation Based on the Discrete Element Method (직접전단시험과 이산요소법에 기반한 전단 시뮬레이션과의 비교)

  • Jung, Sung-Heon;Sohn, Jeong-Hyun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.3
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    • pp.86-91
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    • 2020
  • An important factor of rough road modeling is analyzing the shear behavior properties of the rough road. These properties influence the drawbar pull of the tool when interacting with the soil used in agriculture. Furthermore, shear behavior properties are important because sinkage and shear stress are generated when wheels drive on rough roads. In this study, we performed a direct shear test to investigate the shear behavior properties of soils and compare with the direct shear simulation; shear force derived by the coupled analysis of discrete element method; and multi-body dynamics. Soil contact parameters were measured in a wheel and soil contact simulation followed by comparison of the simulated and experimentally measured shear force.