• Title/Summary/Keyword: T-testing

검색결과 1,521건 처리시간 0.029초

Eddy Current Signal Analysis for Transmit-Receive Pancake Coil on ECT Array Probe

  • Lee, Hyang-Beom
    • 비파괴검사학회지
    • /
    • 제26권1호
    • /
    • pp.25-29
    • /
    • 2006
  • In this paper, the eddy current signals come from a pair oi transmit-receive (T/R) pancake coil on ECT array Probe are analyzed with the variations of the lift-of and of the distance between transmit and receive coils. To obtain the electromagnetic characteristics of the probes, the governing equation describing the eddy current problems is derived from Maxwell's equation and is solved using three-dimensional finite element method. Eddy current signals from T/R coils on ECT array probe have quite different characteristics compared with ones from impedance coil on rotating pancake coil probe. The results in this paper ran be helpful when the field eddy current signals from ECT array probe are evaluated.

IEC947-2에 따른 전자식 저압 차단기의 EMC 시험 고찰 (The study of EMC test for low-voltage circuit-breakers with electronic over-current protection according to IEC947-2)

  • 오준식;김명석;한규환
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
    • /
    • pp.151-153
    • /
    • 2002
  • 전자화 기기의 신뢰성이 요구되는 산업환경에서 외부잡음, 방사잡음, 전도 노이즈 등으로 인한 제품의 오동작 및 기능장해 문제가 발생되고 있다. 저압용 배선용 차단기 또한 네트워크를 통한 통신, 감시(monitoring). 제어(control) 둥의 기능을 구현하기 위한 전자회로를 탑재한 전자식 제품의 개발이 활발이 이루어지고 있으며 정화한 시험을 통한 검증이 필요하다. 본 논문에서는 전자회로 트림장치를 가진 전자식 차단기에 대한 IEC947-2에서 요구하는 EMC 시험방법을 고찰하고자 한다.

  • PDF

미혼 간호사의 Pap 검진의도 영향요인 (Influencing Factors of Intention of Undergoing Pap Testing among Unmarried Nurses)

  • 김혜원
    • 여성건강간호학회지
    • /
    • 제20권3호
    • /
    • pp.225-233
    • /
    • 2014
  • Purpose: This study was to assess the intention of undergoing Pap testing and to identify influencing factors of HPV knowledge and their attitude related to Pap test by sexual activity among unmarried nurses. Methods: A cross sectional survey design was employed, utilizing a self-administered questionnaire amongst 343 unmarried nurses. Descriptive statistics was utilized to analyze data and inferential statistics used an independent-t test and ${\chi}^2$ test for the differences in measurement variables, and odds ratios for factors on intention of Pap testing by sexual activity. Results: Nurses not sexually active were significantly higher in intention of Pap testing (${\chi}^2$=40.15, p<.001) and influencing factors of HPV knowledge (t=3.93, p=.048) than did nurses who were sexually active. Factors influencing intention were regularity of the breast self-examination (Adjusted Odds Ratio [AOR]=4.20, 95% Confidence Interval [CI]=1.93~9.17), HPV knowledge (AOR=2.49, 95% CI=1.36~4.56), and attitudes toward the Pap test(AOR=2.33, 95% CI=1.25~4.34) amongst nurses who never had sexual experience. Conclusion: It is necessary to minimize negative attitudes of Pap testing and to increase HPV knowledge in order to improve intention of Pap testing for women who were not sexually active. More focus would be given to sexually active women to get Pap tested as a preventive measure for cervical cancer.

Analysis of the influence of panel characteristics on odor measurement based on the air dilution olfactory method in Korea

  • Kim, Sun-Tae;Lee, Seokjun;Yim, Bongbeen
    • Environmental Engineering Research
    • /
    • 제24권1호
    • /
    • pp.91-98
    • /
    • 2019
  • This study was to objectify differences in the results of odor testing according to the characteristics of panel members that participate in air dilution olfactory method (ADOM) testing. When differences in the results of olfactory testing were reviewed in relation to characteristics of the panelists, the result of entire panels for the site boundary Proficiency Testing Materials (PTMs) showed no difference according to panelist sex, age, smoking status, and past participation in ADOM tests. As for the outlet PTMs, distinct differences appeared in relation to the smoking status and age of panelists. The frequency distribution for all the panelists (Dev($D/T_{total}$)) showed a form similar to a normal distribution, so it is thought to be more appropriate for the review of effect of panelist characteristics on the result of air dilution olfactory tests. In addition, the ADOM testing method implemented as the standard method for odor compounds in Korea (Dev($D/T_3$)) will have to be implemented along with a concurrent assessment, for the purpose of identifying the effect of panelist characteristics on administrative dispositions against malodors.

홀로그래픽 간섭법을 이용한 진동모드의 계측에 관한 연구 (A Study on the Measurement of Vibration Mode Shape using Holographic interferometry)

  • 김광래
    • 한국생산제조학회지
    • /
    • 제9권3호
    • /
    • pp.130-135
    • /
    • 2000
  • In this study the vibration behavior of the stiffened double cylinder was experimently analyzed. Due to the complex structure of the double cylinder the outside cylinder frequency responses to the exciting forces applied on various posi-tions were analyzed by using spectrum analyzer in conjunction with an accelerometer and the natural frequencies were obtained. The technique of time-averaged holographic interferometry is applied to study the vibration characteristics of outside cylinder with stiffening T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. however the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame. The experimental data showed that the T frame had salient effect of damping on the testing structure at most of resonances. However the experimental results also revealed interesting phenomenon. At some particular frequencies the T frame seemed to behave as a transmitter. In addition it has been successfully demon-started that optical method such as holographic interferometry is well suited for the identification of mode shapes. They can give us a whole-field non-contact measurement instead of the point-wise measurement by accelerometer in classical modal testing.

  • PDF

The Genetic Development of Sire, Dam and Progenies and Genotype ${\times}$ Environment Interaction in a Beef Breeding System

  • Bhuiyan, A.K.F.H.;Dietl, G.;Klautschek, G.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제17권1호
    • /
    • pp.13-17
    • /
    • 2004
  • The aim of this study was to investigate genetic development and genotype${\times}$environment interactions (GEI) in postweaning body weight of fattening bulls at the end of test period (WT-T) under various beef fattening environments. Data on a total of 24,247 fattening bulls obtained from the industrial farm, breeding farms and testing stations were used. Heritability estimates for WT-T in all environments were nearly similar. Significant genetic developments of sire, dam and progenies for WT-T were observed in all environments. However, many differences in annual genetic developments between the environments were significant. The genetic correlations for WT-T between industrial farm and breeding farms, industrial farm and testing stations and breeding farms and testing stations were respectively 0.004, 0.004 and 0.013. These low estimates of genetic correlations and significant differences in genetic developments among environments clearly show the existence of GEI for WT-T among various fattening environments. Results of this study indicate the need for environment-specific genetic evaluation and selection of beef bulls for commercial beef production.

Effect of pH and Concentration on Electrochemical Corrosion Behavior of Aluminum Al-7075 T6 Alloy in NaCl Aqueous Environment

  • Raza, Syed Abbas;Karim, Muhammad Ramzan Abdul;Shehbaz, Tauheed;Taimoor, Aqeel Ahmad;Ali, Rashid;Khan, Muhammad Imran
    • Journal of Electrochemical Science and Technology
    • /
    • 제13권2호
    • /
    • pp.213-226
    • /
    • 2022
  • In the present study, the corrosion behavior of aluminum Al-7075 tempered (T-6 condition) alloy was evaluated by immersion testing and electrochemical testing in 1.75% and 3.5% NaCl environment at acidic, neutral and basic pH. The data obtained by both immersion tests and electrochemical corrosion tests (potentiodynamic polarization and electrochemical impedance spectroscopy tests) present that the corrosion rate of the alloy specimens is minimum for the pH=7 condition of the solution due to the formation of dense and well adherent thin protective oxide layer. Whereas the solutions with acidic and alkaline pH cause shift in the corrosion behavior of aluminum alloy to more active domains aggravated by the constant flux of acidic and alkaline ions (Cl- and OH-) in the media which anodically dissolve the Al matrix in comparison to precipitated intermetallic phases (cathodic in nature) formed due to T6 treatment. Consequently, the pitting behavior of the alloy, as observed by cyclic polarization tests, shifts to more active regions when pH of the solutions changes from neutral to alkaline environment due to localized dissolution of the matrix in alkaline environment that ingress by diffusion through the pores in the oxide film. Microscopic analysis also strengthens the results obtained by immersion corrosion testing and electrochemical corrosion testing as the study examines the corrosion behavior of this alloy under a systematic evaluation in marine environment.

Unbalanced ANOVA for Testing Shape Variability in Statistical Shape Analysis

  • Kim, Jong-Geon;Choi, Yong-Seok;Lee, Nae-Young
    • 응용통계연구
    • /
    • 제23권2호
    • /
    • pp.317-323
    • /
    • 2010
  • Measures are very useful tools for comparing the shape variability in statistical shape analysis. For examples, the Procrustes statistic(PS) is isolated measure, and the mean Procrustes statistic(MPS) and the root mean square measure(RMS) are overall measures. But these measures are very subjective, complicated and moreover these measures are not statistical for comparing the shape variability. Therefore we need to study some tests. It is well known that the Hotelling's $T^2$ test is used for testing shape variability of two independent samples. And for testing shape variabilities of several independent samples, instead of the Hotelling's $T^2$ test, one way analysis of variance(ANOVA) can be applied. In fact, this one way ANOVA is based on the balanced samples of equal size which is called as BANOVA. However, If we have unbalanced samples with unequal size, we can not use BANOVA. Therefore we propose the unbalanced analysis of variance(UNBANOVA) for testing shape variabilities of several independent samples of unequal size.

시편두께 및 균열깊이 영향을 고려한 비표준시편의 J 시험법 및 구속효과의 정량화 (Specimen Thickness and Crack Depth Effects on J Testing and Crack Tip Constraint for Non-standard Specimen)

  • 김진수;조수만;김윤재;김영진
    • 대한기계학회논문집A
    • /
    • 제27권9호
    • /
    • pp.1531-1538
    • /
    • 2003
  • This paper compiles solutions of plastic $\eta$ factors and crack tip stress triaxialites for standard and nonstandard fracture toughness testing specimens, via detailed three-dimensional (3-D) finite element (FE) analyses. Fracture toughness testing specimens include a middle cracked tension (M(T)) specimen, SE(B), single-edge cracked bar in tension (SE(T)) and C(T) specimen. The ligament-to-thickness ratio of the specimen is systematically varied. It is found that the use of the CMOD overall provides more robust experimental J estimation than that of the LLD, for all cases considered in the present work. Moreover, the J estimation based on the load-CMOD record is shown to be insensitive to the specimen thickness, and thus can be used for testing specimen with any thickness. The effects of in-plane and out-of-plane constraint on the crack tip stress triaxiality are also quantified, so that when experimental J value is estimated according to the procedure recommended in this paper, the corresponding crack tip stress triaxiality can be estimated. Moreover, it is found that the out-of-plane constraint effect is related to the in-plane constraint effect.

Active-Sensing Lamb Wave Propagations for Damage Identification in Honeycomb Aluminum Panels

  • Flynn, Eric B.;Swartz, R.Andrew;Backman, Daniel E.;Park, Gyu-Hae;Farrar, Charles R.
    • 비파괴검사학회지
    • /
    • 제29권4호
    • /
    • pp.269-282
    • /
    • 2009
  • This paper presents a novel approach for Lamb wave based structural health monitoring(SHM) in honeycomb aluminum panels. In this study, a suite of three signal processing algorithms are employed to improve the damage detection capability. The signal processing algorithms used include wavelet attenuation, correlation coefficients of power density spectra, and triangulation of reflected waves. Piezoelectric transducers are utilized as both sensors and actuators for Lamb wave propagation. These SHM algorithms are built into a MatLab interface that integrates and automates the hardware and software operations and displays the results for each algorithm to the analyst for side by side comparison. The effectiveness of each of these signal processing algorithms for SHM in honeycomb aluminum panels under a variety of damage conditions is then demonstrated.