• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2174-2183
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• 2000

In this paper, the evaluation method of interfacial fracture toughness to apply the fracture toughness was investigated in adhesively bonded joints of AI/Ced./A1. Four types of adhesively bonded double-cantilever beam(DCB) joints with the interface crack were prepared for the test of interfacial fracture toughness. The experiments to measure the interfacial fracture toughness were performed under the various mixed-mode conditions. The critical energy release rate, Gc, was obtained by the experimental measurement of compliances. From the experimental results, the interfacial fracture toughness for the mixed-mode specimens is well characterized by the energy release rate, and the method of strength evaluation by the interfacial fracture toughness was discussed in adhesively bonded joints.

• 연구논문집
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• s.33
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• pp.67-79
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• 2003

The life of oilless bearing affects the durability of scroll compressor. The main shaft of the scroll compressor is supported by oiiless bearing. Some of the major parameters which influence the life of oilless bearing are rotational speed, normal load, environment of refrigerant and oil film thickness. The reliability evaluation of oiiless bearing is performed through the acceleration life test for reduction of experimental time and costs. In this study, the experimental and computational investigations were performed to verify the effects of various parameters on the life of oilless bearing. The acceleration factor was achieved with the lubrication analysis between the scroll compressor and the developed reliability tester. the expected life of oilless bearing was guaranteed by reliability evaluation accompanied with the acceleration life test.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.3 no.1
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• pp.6-12
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• 1989

Methods of voice rehabilitation in laryngectomees include training of esophageal speech, use of electrolarynx and pneumatic speech aid and surgical methods, etc. In this paper, we introduce the experimental model of obturator-type electrolarynx which has several advantages for use such as ease of learning, no disagreeable appearance, and both hands not being occupied. We compared it to normal voice and other voice rehabilitation methods such as esophageal voice, japanese pneumatic speech aid and cervical electrolarynx in intelligibility and sonagraphic evaluation. The results are as follows; 1) Obturator-type electrolarynx exhibited the lowest intelligibility. 2) In sonagraphic evaluation, the spectrogram produced by the obturator-type electrolarynx was the most different from those of normal voice.

• Geomechanics and Engineering
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• v.29 no.3
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• pp.349-357
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• 2022

Abnormal climate events are occurring frequently around the world. In particular, cold waves and heavy snow lead to damage and deterioration of facilities, which can cause loss of life or property damage, such as shortening the lifespan of facilities. Therefore, it is very important to prepare an appropriate maintenance system and to establish a strategy to cope with abnormal weather conditions. In this study, laboratory freezing experiments were performed to analyze the freeze-thaw characteristics affecting the tunnel concrete lining, and heat flow analysis was carried out based on the test results. Based on these experimental and theoretical analysis results, quantitative freeze-thaw evaluation criteria for tunnel concrete linings were proposed.

• Journal of Korean Elementary Science Education
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• v.26 no.2
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• pp.161-170
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• 2007

This study aims at helping us improve the methods used to teach elementary school students how to handle experimental apparatus by examining their manual skills and their understanding of the alcohol lamp, spuit and thermometer. To evaluate their ability to handle each experimental apparatus, a practical skills test and knowledge evaluation sheets were developed. The evaluation was carried out with 270 students from 2 classes each in the 3rd, 4th, 5th and 6th grade of D Elementary School located in Daejeon City. For their handling ability of the alcohol lamp, the results for the practical skills test showed that the students had a very low ability in placing objects in the center of the apparatus for safe use and also in adjusting the height of the trivet to place objects so that they contact the outer flames correctly. For the spuit, the pass rate of the skills test was generally low in regards to how students should grasp a spuit and the timing and method of depressing the rubber part before dipping it into liquid. For the thermometer, on the other hand, the pass rate was relatively high in every respect. The knowledge evaluation results for the use of experimental apparatus showed a very high rate of correct answers for alcohol lamps and thermometers. The test results for spoils also produced a relatively high rate of correct answers, with the exception of the test item regarding the way that students should grasp them.

• Proceedings of the Safety Management and Science Conference
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• 2009.11a
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• pp.557-563
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• 2009

The research develops measurement processes for estimating and evaluating the gauge R&R(Reproducibility & Repeatability) using ANOVA(Analysis of Variance) of experimental design tools. The ten-step processes developed include experimental goal setting, the selection of characteristics(factors, levels), data model, ANOVA, EMS(Expected Mean Square), estimation of gauge precisions, and evaluation indexes. The three-factor combined measurement models are presented to show the processes developed in this paper.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.243-250
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• 2004

This paper reports on the evaluation of the initial stiffness of steel joints using component method as well as experimental tests. The so-called component method corresponds precisely to a simplified mechanical model composed of extensional springs and rigid links, whereby the joint is simulated by an appropriate choice of rigid and flexible components. An application to a cantilever beam-to-column steel joint is presented and compared to the experimental results obtained under cyclic loading condition. Comparison between numerical and experimental results allows to conclude that the numerical model is able to simulate, with a good level of accuracy for initial stiffness, the behaviour of beam-to-column joints.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.42-45
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• 2017

In this letter, we present an experimental comparative study of background subtraction algorithms for soccer video analysis. We investigated five different background subtraction algorithms under the same experimental setup. For the quantitative comparison, we employed the precision, recall, and F-measure. We believe that this comprehensive comparative study serves as a reference point and guide for developers and practitioners in choosing an appropriate background subtraction algorithm adopted for building intelligent soccer video analysis systems.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.533-544
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• 2002

The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

• Nuclear Engineering and Technology
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• v.34 no.4
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• pp.370-381
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• 2002

The neutron induced nuclear data for Pr-141, Nd-143, Nd-145, Sm-147 and Sm-149 were calculated and evaluated from 10 keV to 20 MeV. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated. Spherical optical model , statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were introduced in Empire calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files. The model calculated total and capture cross sections were in good agreement with the reference experimental data. The capture cross sections in pre-equilibrium were enhanced in recent released Empire version. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.