• Tunnel and Underground Space
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• v.22 no.5
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• pp.330-338
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• 2012

Though the uniaxial compressive strength (UCS) of rock material is one of the key properties for rockmass characterization purposes, core samples for the test cannot always be obtained from the field. Indirect tests such as the point load test (PLT) can be a useful alternative. In this study, correlation between the UCS and the point load strength index of limestone of Imgye area was analyzed, and the linear regression equation obtained from regression analysis of two variables was suggested. The results of this study were also compared with previous studies on limestone. It was suggested that conversion factors for the same rock type from diverse areas in Korea may have different values, and more data should be obtained to increase the accuracy of regression analysis.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1614-1628
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• 2016

The purpose of this study was to examine the relationship between the safety awareness and safety practice of international marriage woman in Kimhae and Changwon city. We carried out a questionnaire survey that was targeted at 138 subjects. Data collected were analyzed with SPSS 21.0 statistical program. Analysis methods were t-test, one way ANOVA, Scheffe test, Perarsons correlation coefficient, and multiple linear regression. The results were as follows. First, safety awareness point was an average of 4.10 point which was higher level. Safety practice point was an over intermediate level of an average of 3.23 point. Second, safety awareness had statistically significant difference according to age, year of Korea residence, born Nation, whether or not Korean citizenshilp, monthly income, temper, satisfaction of marriage. Third, safety practice had statistically significant difference according to housing, monthly income, health state, satisfaction of marriage. Fourth, safety Practice had a positive correlation with home safety awareness, traffic safety awareness, fire safety awareness, and emergency care awareness. Therefore, a higher safety awareness results in having a very well safety practice. Fifth, International Marriage Women from Japan had the highest the level in the Safety Awareness and Safety Practice. From now on, two cities should have a major concern for safety education of fire and emergency care. And the safety education based on learning need analysis need to be done substantially.

• Journal of KIISE:Information Networking
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• v.37 no.1
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• pp.8-15
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• 2010

In this study, we present an extended complex event model by considering both of the complex event and the aspect-oriented programming. We propose an advanced scheme for the event specification suited for the event correlation based network management systems by merging these two models. Specifically, we extend the model to support hierarchical event structures and let the model recognize point-cuts of aspect-oriented programming as events. We provide the event operators designed to specify the events on instances and handle temporal relations of the instances. Lastly, we compare the proposed model with other event models and present the benefits of it.

• Journal of Smart Tourism
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• v.3 no.1
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• pp.9-21
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• 2023

This study investigated whether the Point of attachment (POA) theory can be used to measure the consumption intention on go and watch offline eSports games. The admiration for players, social interaction, and on-site consumption requirements for viewing offline eSports competitions are prioritized. In addition, eSports fans in various regions may have distinct consumption concepts and consumption patterns. Thus, this study surveyed China (n = 156) and South Korea (n = 127) eSports fans who subjectively perceive themselves to be fans of eSports player(s) and who have observed at least one offline eSports game. The results demonstrate that player attraction and socialization have positive and significant effects on offline consumption factors. There is no correlation between previous consumption behavior and satisfaction, but dining shows a significant positive effect on satisfaction. Moreover, there is a strong relationship between satisfaction and future attendance intention. In addition, effect of eSports fan attachment on future visit intentions are measured and there is no correlation between the two variables. The front end of the path in the new model's varied between Chinese and Korean supporters. Finally, theoretical and practical implications of this study are discussed.

• 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.

• Publications of The Korean Astronomical Society
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• v.19 no.1
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• pp.1-10
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• 2004

On the framework of a linearly perturbed Friedmann-Robertson-Walker spacetime, we derive an expression for the cosmological angular diameter distance affected by scalar and tensor perturbations. Our expression is applicable in linear order to distances in general FRW models. We study the effect of a stocastic gravitaional wave background on the two-point correlation function of the angular diameter distance fluctuations and, on the basis of this we also derive an expression for the power spectrum of the angular diameter distance fluctuations.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1264-1281
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• 2008

Around two years have passed since the beginning of aptitude test required by 2006 Rail Safety Act. At this point, it is necessary to evaluate the validity of the aptitude test. Through this study, the structural system for all the tests would be overviewed, which will show the correlation among each tests or its importance. Also, although it is rough, reliability and validity of the tests would be overviewed by their retest and education materials. This would contribute, in the future, to setting up for the standard of upgrading or integrating the tests.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.264-273
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• 2015

This presentation describes an experimental approach for the detection of cavitation in hydraulic machines by use of ultrasonic signal analysis. Instead of using the high frequency pulses (typically 1MHz) only for transit time measurement different other signal characteristics are extracted from the individual signals and its correlation function with reference signals in order to gain knowledge of the water conditions. As the pulse repetition rate is high (typically 100Hz), statistical parameters can be extracted of the signals. The idea is to find patterns in the parameters by a classifier that can distinguish between the different water states. This classification scheme has been applied to different cavitation sections: a sphere in a water flow in circular tube at the HSLU in Lucerne, a NACA profile in a cavitation tunnel and two Francis model test turbines all at LMH in Lausanne. From the signal raw data several statistical parameters in the time and frequency domain as well as from the correlation function with reference signals have been determined. As classifiers two methods were used: neural feed forward networks and decision trees. For both classification methods realizations with lowest complexity as possible are of special interest. It is shown that two to three signal characteristics, two from the signal itself and one from the correlation function are in many cases sufficient for the detection capability. The final goal is to combine these results with operating point, vibration, acoustic emission and dynamic pressure information such that a distinction between dangerous and not dangerous cavitation is possible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.985-990
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• 2004

Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband noise from a leak location and can be propagated to both directions of water pipes. This sound propagation due to leak in water pipelines is not a non-dispersive wave any more because of the surrounding pipes and soil. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300m.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.798-803
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• 2004

Leak noise is a good source to identify the exact location of a leak point of underground water pipelines. Water leak generates broadband sound from a leak location and this sound propagation due to leak in water pipelines is not a non-dispersive wave any more because of the surrounding pipes and soil. However, the necessity of long-range detection of this leak location makes to identify low-frequency acoustic waves rather than high frequency ones. Acoustic wave propagation coupled with surrounding boundaries including cast iron pipes is theoretically analyzed and the wave velocity was confirmed with experiment. The leak locations were identified both by the acoustic emission (AE) method and the cross-correlation method. In a short-range distance, both the AE method and cross-correlation method are effective to detect leak position. However, the detection for a long-range distance required a lower frequency range accelerometers only because higher frequency waves were attenuated very quickly with the increase of propagation paths. Two algorithms for the cross-correlation function were suggested, and a long-range detection has been achieved at real underground water pipelines longer than 300m.