• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.415-420
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• 2010

This paper describes the design overview of shared file system $SANique^{TM}$ and analyzes the performance evaluation results of I/O intensive stress test based on various cluster file system architectures. Especially, we illustrate the performance analysis for the comparison results between the $SANique^{TM}$ and the Linux file system EXT3 system that is used to generally in Unix world. In order to perform our evaluation, Oracle 10g database system is operated on the top of cluster file system, and we developed the various kinds of testing tools which are compiled by ESQL/C from Oracle. Three types of architectures are used in this performance evaluation. Those are the cluster file system $SANique^{TM}$, EXT3 and the combined architecture of $SANique^{TM}$ and EXT3. In this paper, we present that the results of $SANique^{TM}$ outperforms other cluster file systems in the overhead for providing the true sharing over the connecting server nodes.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.4
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• pp.439-445
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• 2020

In this paper, the seismic performance evaluation was performed on 100 existing open-cut power cable tunnels, including ones that did not consider seismic design, in order to verify that the government's demand level (seismic special grade, 0.22 g). The results of the seismic performance evaluation show that most of the tunnels have seismic performance of 0.3 to 1 g, satisfying the level of the seismic special grade and securing the seismic safety. Meanwhile, the earthquake response analysis and structural test were performed to verify the validity of the method and the results of the seismic performance evaluation of the tunnels by the response displacement method, and to verify their seismic safety. As a result, the relative displacement due to the response displacement method under the 0.22 g earthquake was conservative than the results of the earthquake response analysis, and the results of load-displacement curves and response modification coefficient calculation by real scale structural tests showed the safety of the tunnels.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.932-938
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• 2002

In structural applications, brittle materials such as soda-lime glasses and ceramics are usually subjected to multiaxial stress state. Brittle materials with cracks or damage by foreign object impacts are apt to fracture abruptly from cracks, because of their properities of very high strength and low fracture toughness. But in most cases, the residual strength of structural members with damage has been tested under uniaxial stress condition such as the 4-point bend test. Depending upon the crack pattern developed, the strength under multiaxial stress state might be different from the one under uniaxial. A comparative study was carried out to investigate the influence of stress state on the residual strength evaluation. In comparable tests, the residual strength under biaxial stress state by the ball-on-ring test was greater than that under the uniaxial one by the 4-point bend test, when a small size indendation crack was introduced. In the case that crack having an angle of 90deg. to the applied stress direction, the ratio of biaxial to uniaxial flexure strength was about 1.12. The residual strength was different from crack angles to loading direction when it was evaluated by the 4-point bend test. The ratio of residual strength of 45deg. crack to 90deg. one was about 1.20. In the case of specimen cracked by a spherical impact, it was shown that an overall decrease in flexure strength with increasing impact velocity, and the critical impact velocity for formation of a radial and/or cone crack was about 30m/s. In those cases that relatively large cracks were developed as compared with the case of indented cracks, the ratio of residual strength under biaxial stress state to one uniaxial became small.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.223-229
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• 2016

In this study, a cold forging process was developed for the roller tappet housing of an engine valvetrain system. A tappet sample was manufactured and subjected to an endurance test. The material properties were obtained from a compression test, and forging analysis was carried out to design a forging process using a commercial program, Deform-3D. The forging process was set up based on the analysis results, and a die set and sample tappet housing were manufactured. To evaluate the sample, the dimensional accuracy, surface roughness, parallelism, and concentricity were measured and confirmed. To evaluate the actuation and durability, a special test rig was developed to simulate the valvetrain system of the engine. An actuation test was performed based on the idle speed of a general diesel engine, and an endurance test was done based on the maximum speed. The results show minor wear of 0.002 mm. The developed test rig will be used to evaluate the actuation and durability of other valvetrain parts.

• Journal of the Korean Society of Physical Medicine
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• v.17 no.3
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• pp.51-58
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• 2022

PURPOSE: This study aimed to evaluate the correlation between executive function and gait evaluations for the elderly, and validate the obstacle gait evaluation as a cognitive impairment test tool. METHODS: This study was a cross-sectional design. 79 people aged 65 years or older were selected as subjects. The Korean version of the Mini-Mental State Examination (MMSE-KC) to evaluate overall cognitive function and the Trail Making Test (TMT) A, B to measure executive function were performed. The 4-meter walking speed test and the walking speed test while crossing over an obstacle were carried out to evaluate gait. The Spearman's correlation was used to measure the correlation between cognition and gait speed. RESULTS: There was no significant correlation between the 4 m gait speed and executive function( TMT-A (p = .056), TMT-B (p = .115)). However, there was a significant correlation between the 4 m gait speed and MMSE-KC (r = .277, p < .05). There was also a significant correlation between walking speed while crossing over an obstacle and all tests (MMSE-KC (r = .382, p < .01). TMT-A (r = -.327, p < .01), TMT-B (r = -.283, p < .05)). CONCLUSION: It was found that the gait speed while crossing over an obstacle was correlated with all cognitive function tests. Therefore, we suggest the use of the gait speed test while crossing over an obstacle rather than the simple gait test to diagnose cognitive decline.

• The Research Journal of the Costume Culture
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• v.17 no.3
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• pp.523-534
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• 2009

The purpose of this study is to categorize the dimensions of the visual evaluation of the costume details of the retro romantic fashion and to research on the costume details and the visual evaluation by evaluators' gender, age, and major, and on their preferences. Quantitative research were conducted for this study. Based on the pictures, 10 costume details were selected for the survey questions and data were collected. All 446 subjects who participated in this research were college students(males and females) residing in or near Seoul. Data were collected in September, 2008. The collected data were statistically analyzed using SPSS which included: factor analysis, Cronbach's $\alpha$ reliability analysis, three-way ANOVA, two-way ANOVA, one-way ANOVA, Duncan's multiple range tests, and the t-test. The results of visual evaluation of retro romantic fashion are as follows: First, as a result of the factor analysis of the costume detail evaluation, five factors including attractiveness, decorativeness, cuteness, retro, and femininity surfaced. Second, the gender difference in the results of the research revealed that women rated decorative, cute, retro, and feminine characteristics higher than men did. Third, there were significant interactive effects in attractiveness and femininity depending on costume details and evaluators' gender. Fourth, subjects majoring in fashion valued attractiveness and femininity of the stimulus over non-fashion majoring subjects. Fifth, there were significant differences in the preferences of costume details depending on gender.

• The KSFM Journal of Fluid Machinery
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• v.3 no.4 s.9
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• pp.7-14
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• 2000

This paper provides integrity evaluation and root cause analysis for defects observed at volute tongue, or cutwater, of the operating centrifugal pump in power plant. The cause of the cracks are analyzed and reviewed from the viewpoint of the operation and maintenance of the pumps, and the sample obtained from the cracked volute tongue of the pump are examined. At first, in-situ hardness test and microstructure examination were performed to understand the cause of cracking at volute tongue. The evaluation of structural integrity and the possibility of the crack propagation is also evaluated. Cracks were typical intergranular cracking and propagated along with prior austenite grain boundary. At easing volute tongue, the hardness was higher than ASTM requirement and a large amount of intergranular Cr carbide was precipitated. These were due to high C content in material. P content was also higher than ASTM requirement. Therefore, Cr carbide precipitation and P segregation at grain boundary, caused by higher C and P content in material, resulted in intergranular cracking of casing volute tongue. This procedure for integrity evaluation and root cause analysis is used to guide, and support the pump designer and manufacturer's material selection and process design to avoid a costly, unplanned outage of plant.

• Journal of the Korean Society for information Management
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• v.29 no.1
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• pp.211-229
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• 2012

This study aims to enhance the usability of eBook reader programs on personal computers through heuristic evaluation in order to learn users' perceptions and derive key elements for interface design. For this purpose, the traditional usability evaluation and heuristic evaluation method were studied. A total of 22 evaluators of the heuristic evaluation were taken by purposive sampling to test the interface of eBook reader on PCs. This study suggested ten heuristics that focus on improving and specializing the usability aspects of reading digital materials.

• Fashion & Textile Research Journal
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• v.21 no.1
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• pp.75-87
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• 2019

The purpose of the study was to suggest a cycle wear top jersey improved in mobility. The study developed a new cycle wear with improvement in dissatisfaction factors by planning design, pattern and the functionality of fabric. Considering the amount of sweat and the necessities of compression part, the basic material, the additional compression material, and the mesh material were arranged differently according to areas. The assessment of the developed cycle wear was composed of wearing comfort evaluation by female cyclist, photo analysis and garment pressure evaluation. The developed cycle wear was evaluated and compared with the current cycle wear. As a result of wearing comfort evaluation, the developed cycle wear was evaluated as better than the existing ones in all part, particularly in the areas of reflection tape and materials, partial pressure, pocket size, and prevention of loss. Photo analysis was in agreement with the appearance evaluation of the participants. As a result of garment pressure evaluation, the front neck part was more comfortable and the upper arm, abdomen, and waist area showed higher pressure, so it partially supported the body. This study has significant meaning for developing a new cycle wear top, protecting the body and improving the exercise effect.

• Journal of Korean Academy of Nursing
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• v.33 no.5
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• pp.643-650
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• 2003

Purpose: This study was conducted to examine the effect of a posture training program, including posture education and spinal exercise as implemented on the elementary school students with scoliosis. Method: The design of this study is nonequivalent sample control group pretest-posttest design. The study subjects were elementary school students attending 7 elementary schools located in G city in Gyungsangbuk-Do. Among them, those who had the Cobb angle between 4～10$^{\circ}$ in spine x-ray who agreed to participate in the study program were selected as the study subjects. The research instruments included the degree of spinal scoliosis(cobb angle), the level of knowledge on posture, and an evaluation following the posture training program. The data were collected from March 1, 2002 to July 30, 2002. The collected data were analyzed by frequency, percentile, mean, standard deviation, t-test, i test and Mann-Whitney U test were using SPSS WIN10.0 program. Result: The elementary school students with scoliosis who received the posture training program have a lower Cobb angle and higher level of knowledge of posture than the elementary school students with scoliosis who did not receive the posture training program. Conclusion: The posture training program was effective on the on Cobb angle and Knowledge of posture in the elementary school students with scoliosis in this study. Therefore, the program training program can be usefully utilized for the students with mild scoliosis in the field of school health.