• Journal of Soil and Groundwater Environment
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• v.25 no.4
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• pp.35-47
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• 2020

Step-drawdown test is one of the widely-used aquifer test methods to evaluate aquifer and well losses. Various approaches have been suggested to estimate well losses using the step-drawdown test data but the uncertainties associated with data interpretation and analysis still exist. In this study, we applied three different step-drawdown test analysis methods -Jacob (1947), Labadie and Helweg (1975), Gupta (1989)- to the step-drawdown test data in Seobu-myeon, Hongseong-gun, South Korea and estimated aquifer and well losses. Comparisons of different step-drawdown test analysis methods revealed that the estimated well losses showed different values depending on the applied methods and these variations are likely to be related to the limitation of the assumptions for each analysis method. Based on the detailed analysis of time-drawdown data, we performed step-drawdown test analysis after removing outlier data during the initial stage of step drawdown test. The results showed that the application of the revised time-drawdown data could substantially decrease the error of the analysis as well as the variations in the estimated well losses from different analysis methods.

• Journal of Information Processing Systems
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• v.7 no.2
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• pp.363-384
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• 2011

As the complexity of software is increasing, generating an effective test data has become a necessity. This necessity has increased the demand for techniques that can generate test data effectively. This paper proposes a test data generation technique based on adequacy based testing criteria. Adequacy based testing criteria uses the concept of mutation analysis to check the adequacy of test data. In general, mutation analysis is applied after the test data is generated. But, in this work, we propose a technique that applies mutation analysis at the time of test data generation only, rather than applying it after the test data has been generated. This saves significant amount of time (required to generate adequate test cases) as compared to the latter case as the total time in the latter case is the sum of the time to generate test data and the time to apply mutation analysis to the generated test data. We also use genetic algorithms that explore the complete domain of the program to provide near-global optimum solution. In this paper, we first define and explain the proposed technique. Then we validate the proposed technique using ten real time programs. The proposed technique is compared with path testing technique (that use reliability based testing criteria) for these ten programs. The results show that the adequacy based proposed technique is better than the reliability based path testing technique and there is a significant reduce in number of generated test cases and time taken to generate test cases.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.369-374
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• 2004

Web-based analysis programs for reliability assessment of machine tools were developed in this study. First, the reliability data analysis program was developed to search for failure rate using failure data and reliability test data of mechanical part. Second, failure mode analysis was developed through performance tests like circular movement test vibration test for machine tools. This analysis program shows correlation between failure mode and performance test result. Third, tool life was predicted by correlation between flank wear and cutting time, using the extended Taylor tool life equation in turning data and the equivalently converted equation in order to apply ball endmill data to Taylor tool life equation in milling data. All the information related to input and result data can be stored in theses programs.

• Journal of Environmental Impact Assessment
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• v.4 no.2
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• pp.93-103
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• 1995

This study was carried out to suggest the best statistical test to analyze the trend in monthly water quality data. Traditional parametric tests such as t-test and regression analysis are based on the assumption that the underlying population has a normal distribution and regression analysis additionally assumes that residual errors are independent. Analyzing 9-years monthly COD data collected at Paldang in Han River, the underlying population was found to be neither normal nor independent. Therefore parametric tests are invalid for trend detection. Four Kinds of nonparametric statistical tests, such as Run Test, Daniel test, Mann-Kendall test, and Time Series Residual Analysis were applied to analyze the trend in the COD data, Daniel test and Mann-Kendall test indicated upward trend in COD data. The best nonparametric test was suggested to be Daniel test, which is simple in computation and easy to understand the intuitive meaning.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.2
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• pp.60-65
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• 2013

Data from repeated measurements are accomplished through repeatedly processing the same subject under different conditions and different points of view. The power of testing enhances the choice of pertinent analysis methods that agrees with the characteristics of data concerned and the situation involved. Along with the clinical example, this paper compares the analysis of the variance on ex-post tests, gain score analysis, analysis by mixed design and analysis of covariance employable for repeating measure. Comparing the analysis of variance on ex post test, and gain score analysis on correlations, leads to the fact that the latter enhances the power of the test and diminishes the variance of error terms. The concluded probability, identified that the gain score analysis and the mixed design on interaction between "between subjects factor" and "within subjects factor", are identical. The analysis of covariance, demonstrated better power of the test and smaller error terms than the gain score analysis. Research on four analysis method found that the analysis of covariance is the most appropriate in clinical data than two repeated test with high correlation and ex ante affects ex post.

• Journal of Korea Multimedia Society
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• v.13 no.12
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• pp.1814-1819
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• 2010

Since 1987, when statistical analyzing guide for thermal life test of Accelerated Life Test(ALT) was proposed as ANSI/IEEE Std 101, this guide has been used widely for many experiment data. Shim(2004) had done Monte Carlo simulation to compare life of two different systems or materials, based on statistic values obtained from ANSI/IEEE Std 101 data. In this study, a profile analysis is proposed for comparing life of two different systems or materials, and some examples using pre-existing data are given.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.2
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• pp.123-132
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• 2003

The quality certification test is usually conducted by a certifying organization to determine and guarantee the quality of software after the software development phase, commonly without the actual source code, but with by going against the product's manual. In this paper, we implement a Manual-based Automatic Test data generating tool: MaT, the test technique based on manual, that automatizes producing the test data from analysis data of software package and manual. The input data of MaT are the result of the analysis of software and manual. We propose 'menu-based test analysis model' in order to generate the input data. We believe that the proposed technique and tool he]p improving quality and reliability of the software.

• 한국기계연구소 소보
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• s.9
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• pp.183-191
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• 1982

This report describes the analysis method of the full-scale propulsive performance by using the data of model test and the full-scale speed trial. The model test data were analyzed by the computer program "PPTT" based on "1978 ITTC Performance Prediction Method for Single Screw Ships." Also the full-scale speed trial data were analyzed by the computer program "SSTT" based on the newly proposed “SRS-KIMM Standard Method of Speed Trial Analysis." An analysis of model and full-scale test data was carried out for a 60.000 DWT Bulk Carrier and the correlation between model and full-scale ship was stuied.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.1
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• pp.15-23
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• 2005

For reliability assessment for machine tools, failure mode analyses by two viewpoints were studied in this paper. First, this study developed the reliability data analysis program, which searches f3r optimal failure distribution like failure rate or MTBF(Mean Time Between Failure) using failure data and reliability test data of mechanical parts in the web. Moreover, this data analysis program saves both failure data or reliability data and their failure rate or MTBF for database establishment. Second, this paper conducted failure mode analysis through such performance tests as circular movement test and vibration testing for machine tools when reliability data is not available. A developed web-based analysis program shows correlations between failure mode and performance test result and also accumulates all the data. These kinds of data analysis programs and stored data furnish valuable information for improving the reliability of mechanical system.

• Journal of Aerospace System Engineering
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• v.9 no.1
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• pp.28-34
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• 2015

Armed aircraft of a basic trainer class installs external stores under wing box by using pylon and performs an operation such as weapon delivery and jettison, and should be designed to withstand all kinds of loads applied to external stores. The static strength test of pylons and wing box was performed to assess the static strength of pylon and their support structures for substantiation. Based on the test, the structures were verified to fully satisfy a given design requirement. In this paper, methods of test load generation of wing box and pylon, evaluation of test result data and design result of test set-up were presented. Comparing the FEM analysis with the same test data can lead to good match and reasonable deviation between both. Finally, based on the test and the analysis, the static strength of test article was substantiated and the reliability and effectiveness of analysis math model were obtained.