• Title/Summary/Keyword: test methods

Search Result 27,418, Processing Time 0.05 seconds

Comparison of measurement uncertainty calculation methods on example of indirect tensile strength measurement

  • Tutmez, Bulent
    • Geomechanics and Engineering
    • /
    • v.12 no.6
    • /
    • pp.871-882
    • /
    • 2017
  • Indirect measure of the tensile strength of laboratory samples is an important topic in rock engineering. One of the most important tests, the Brazilian strength test is performed to obtain the tensile strength of rock, concrete and other quasi brittle materials. Because the measurements are provided indirectly and the inspected rock materials may have heterogeneous properties, uncertainty quantification is required for a reliable test evaluation. In addition to the conventional measurement evaluation uncertainty methods recommended by the Guide to the Expression of Uncertainty in Measurement (GUM), such as Taylor's and Monte Carlo Methods, a fuzzy set-based approach is also proposed and resulting uncertainties are discussed. The results showed that when a tensile strength measurement is measured by a laboratory test, its uncertainty can also be expressed by one of the methods presented.

The Effect of Core Muscle Training Program on Balance Ability

  • Hwang, Hyun Sook;Kim, Nyeon Jun
    • Journal of International Academy of Physical Therapy Research
    • /
    • v.8 no.2
    • /
    • pp.1175-1181
    • /
    • 2017
  • The purpose of this study was to investigate the effects of core muscle training on balance ability. Forty subjects in their 20s participated in a 6 week core muscle training program. Balance ability before and after the intervention were assessed and analyzed using the Romberg test, which was conducted on the floor, pedalo, and balancefit. The differences between the measurement methods of balance ability using varied platforms was also compared and analyzed. After the 6-week core exercise training program, the training group represented statistically significant increases in all 3 methods for static balance ability. In the control group, all 3 methods represented no statistically significant increases. Upon comparing the different methods of the Romberg test, there were no notable differences between conducting the test on varying platforms for both groups. This study suggests that the core muscle exercise training program increased the balance ability.

A new extension of Lindley distribution: modified validation test, characterizations and different methods of estimation

  • Ibrahim, Mohamed;Yadav, Abhimanyu Singh;Yousof, Haitham M.;Goual, Hafida;Hamedani, G.G.
    • Communications for Statistical Applications and Methods
    • /
    • v.26 no.5
    • /
    • pp.473-495
    • /
    • 2019
  • In this paper, a new extension of Lindley distribution has been introduced. Certain characterizations based on truncated moments, hazard and reverse hazard function, conditional expectation of the proposed distribution are presented. Besides, these characterizations, other statistical/mathematical properties of the proposed model are also discussed. The estimation of the parameters is performed through different classical methods of estimation. Bayes estimation is computed under gamma informative prior under the squared error loss function. The performances of all estimation methods are studied via Monte Carlo simulations in mean square error sense. The potential of the proposed model is analyzed through two data sets. A modified goodness-of-fit test using the Nikulin-Rao-Robson statistic test is investigated via two examples and is observed that the new extension might be used as an alternative lifetime model.

A Study on Test Methods for Performance Appraisal of Root Barrier Appling to Green Roofs (옥상 및 인공지반녹화용 방근재의 성능기준 설정을 위한 방근성 시험방법에 관한 연구)

  • Oh, Sang-Keun;Kwak, Kyu-Sung;Sun, Yoon-Suk;Kwon, Shi-Won
    • Journal of the Korea Institute of Building Construction
    • /
    • v.7 no.1 s.23
    • /
    • pp.79-84
    • /
    • 2007
  • Selection of proper root barrier as destination part of greening is very important in Root penetration resistance plan. To select proper root barrier, it need to understand composition of greening part, size, kind of plant, connection with waterproofing layer. In this point of view, we have establish greening on the roof or concrete structure, not been understand the structural mechanism. It means that we misunderstood about purpose of greening and using it. So, chosen materials and construction method was not proper for greening, it caused water leakage and decrease performance of concrete structure. Therefore, we would suggest 5 items of test methods considering environmental condition for green roof. Watertightness by water of greening part, root penetration resistance test by root penetration, bacteria resistance by must or bacteria in soil, chemical resistance by rain and chemical agent of fertilizer, and load resistance by soil depth, size of plant. These suggested test methods could be referred as guideline to test in green roof system because of not exist any performance appraisal guideline or standard. Consequently, it should be analysis as technical and institutional subdividing test methods and it need to study constantly as varied angles.

Performance Comparison of GPS Fault Detection and Isolation via Pseudorange Prediction Model based Test Statistics

  • Yoo, Jang-Sik;Ahn, Jong-Sun;Lee, Young-Jae;Sung, Sang-Kyung
    • Journal of Electrical Engineering and Technology
    • /
    • v.7 no.5
    • /
    • pp.797-806
    • /
    • 2012
  • Fault detection and isolation (FDI) algorithms provide fault monitoring methods in GPS measurement to isolate abnormal signals from the GPS satellites or the acquired signal in receiver. In order to monitor the occurred faults, FDI generates test statistics and decides the case that is beyond a designed threshold as a fault. For such problem of fault detection and isolation, this paper presents and evaluates position domain integrity monitoring methods by formulating various pseudorange prediction methods and investigating the resulting test statistics. In particular, precise measurements like carrier phase and Doppler rate are employed under the assumption of fault free carrier signal. The presented position domain algorithm contains the following process; first a common pseudorange prediction formula is defined with the proposed variations in pseudorange differential update. Next, a threshold computation is proposed with the test statistics distribution considering the elevation angle. Then, by examining the test statistics, fault detection and isolation is done for each satellite channel. To verify the performance, simulations using the presented fault detection methods are done for an ideal and real fault case, respectively.

Application of the New Degree of Compaction Evaluation Method (새로운 다짐도 평가기법의 적용성에 관한 연구)

  • Park, Keun-Bo;Kim, Ju-Hyong
    • Journal of the Korean Geotechnical Society
    • /
    • v.28 no.2
    • /
    • pp.5-14
    • /
    • 2012
  • CMV(Compaction Meter Value) obtained from compaction results using an accelerometer, which measures the impact on the ground and the resilient force of the ground, is compared with the other degree of compaction through regression analysis. As a result, there is no correlation between results from conventional test methods (e.g., the plate load test and field density test) and the degree of compaction evaluated by either the Geogauge or the dyanamic cone penetrometer. To assess the possibility of replacing the conventional test methods with new test methods using CMV, several degrees of compaction tests were carried out. Those results show that the CMV obtained from compaction results using an accelerometer can be used as a substitute for conventional methods to evaluate the stiffness characteristics of compacted soil.

A Study on the Standardization of Fineness Measurement for the Thermal Insulator of Military Textiles (방한용 화섬솜의 섬도 측정방법의 표준화에 관한 연구)

  • Hong, Seong-don;Kim, Byung-soon
    • Journal of Korean Society for Quality Management
    • /
    • v.43 no.3
    • /
    • pp.253-272
    • /
    • 2015
  • Purpose: The purpose of this study is to enhance the reliability of quality inspection by standardize the fineness test method of the thermal insulator of military textiles Methods: We have measured the thermal insulator of military textiles by microscope with three different ways and the effectiveness of their difference were analyzed by one-way layout design. Results: We have suggest the standardized the fineness test method of the thermal insulator of military textiles through advanced research. As a result we have verified hollow ratio of heat insulating fiber affect fineness test methods. The fineness test method for the thermal insulator applied with different methods following hollow ratio. We have verified that when the hollow ratio over 90%, the fineness of the thermal insulator measured from fiber-length, if it has over 80%, the cross-section length of hollow and if it has less 80%, the cross-section area of hollow is applied, respectively. Conclusion: This study indicated that the test method of fineness shows high reliability. Heat insulating fibers which have high evenness shows narrow variations(5/% or less, only CV 25%) irrespectively under different testing equipment or institute. Based ons the results, we have suggest the standardization of test methods for fineness by microscope method and produced the registration of Group Standard in Korean Standards Association.

Development of Automated Rapid Influenza Diagnostic Test Method Based on Image Recognition (영상 인식 기반 신속 인플루엔자 자동 판독 기법 개발)

  • Lee, Ji Eun;Joo, Yoon Ha;Lee, Jung Chan
    • Journal of Biomedical Engineering Research
    • /
    • v.40 no.3
    • /
    • pp.97-104
    • /
    • 2019
  • To examine different types of influenza diagnostic test kits automatically, automated rapid influenza diagnostic test method based on image recognition is proposed in this paper. First, the proposed methods classify a variety of the rapid influenza diagnostic test kit based on support vector machine that analyzes the kits' feature point. Then, to improve the accuracy of test, the proposed methods match the histogram of both the target image of influenza kit and the input image of influenza kit for minimizing the effect of environment factors, such as lighting and exposure variations. And, to minimize the effect from composition of the hand-helds devices, the proposed methods extract the feature point and match point-by-point between target image of influenza kit and input image of influenza kit. Experimental results of 124 experimental group show that the proposed methods significantly have effectiveness, which shows 90% accuracy in moderate antigen, for the preliminary examination of influenza, and provides the opportunity for taking action against influenza.

A Review of Statistical Analysis Methods Applied on Traditional Korean Medicine Research (한의학 연구에 활용된 통계분석 방법에 대한 고찰)

  • Jang, Seon-Il;Yun, Young-Gab;Choi, Kyoung-Ho
    • Herbal Formula Science
    • /
    • v.17 no.1
    • /
    • pp.75-83
    • /
    • 2009
  • Objective : The purpose of this study is to indicate of problems in statistical analysis method of "The Korean Journal of oriental Medical Prescription" and we will be proposed the useful application of the statistical analysis method. Methods : In this paper, we were analysed statistical analysis methodology from published journal articles "The Korean Journal of Oriental Medical Prescription" December, year 2000 to December, year 2008. We were investigated of problems in application of structured analysis methods those journal articles that including statistical analysis techniques and analysis methods. Results : 1. A random allocation of the experimental group and control groups are important factors in the planning process of statistical analysis. However, there are less explanation those journal articles. 2. There are no consideration in specimen size that there will be considerate by the level of significance and statistical test. 3. Many article authors were confused between parametric methods and non-parametric methods that they were applied parametric statistical analysis methods although inapplicable sample size. 4. There were applied the parametric methods consists of t-test instead non-parametric methods in the comparison of average intergroup relations. 5. There were less understanding posterior analysis and were confused with t-test. Conclusion : Our goal was to outline the key methods with a brief discussion of problems(statistical analysis methods), avenues for solutions. we recommend authors to use an appropriate statistical analysis methods for obtaining a more cautions results.

  • PDF

Estimation of slope , βusing the Sequential Slope in Simple Linear Regression Model

  • Choi, Yong;Kim, Dongjae
    • Communications for Statistical Applications and Methods
    • /
    • v.10 no.2
    • /
    • pp.257-266
    • /
    • 2003
  • Distribution-free estimation methods are proposed for slope, $\beta$ in the simple linear regression model. In this paper, we suggest the point estimators using the sequential slope based on sign test and Wilcoxon signed rank test. Also confidence intervals are presented for each estimation methods. Monte Carlo simulation study is carried out to compare the efficiency of these methods with least square method and Theil´s method. Some properties for the proposed methods are discussed.