• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.115-126
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• 2017

This paper proposes an accelerated life evaluation of drive shaft for the power train parts of special purpose vehicle. It is necessary the real load data of usage level driving load condition for life evaluation of power train parts, but we can't get the load spectrum data for evaluation in many case of special purpose vehicle. So, in this paper, the road load spectrum data for evaluation is created by modeling and simulation based on vehicle data and special road condition. The inverse power model is used for accelerated life test. The equivalent torque of load spectrum is achieved using the Miner's Rule. This paper also proposes the calibrated acceleration life test method for drive shaft. The fatigue test is performed through three stress levels. The lifetime at normal stress level is predicted by extrapolation, and is verified through comparison of experimental results and load spectrum data.

• Journal of Life Science
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• v.9 no.6
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• pp.704-708
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• 1999

This research was carried out for evaluating diagnostic value of antibody test in Fragile X syndrome. In antibody test of control individuals and carriers with a premutation, FMRP were detected in the lymphocytes, whereas the lymphocytes of male Fragile X syndrome patients were devoid of FMRP. Five Fragile X syndrome male patient, two Fragile X syndrome female patients, three carriers were diagnosed by southern blot. Five boys who were diagnosed as the patients by antibody test were turned out full mutation and having multiple smear beside normal single band. However, fragile site of X chromosome was not expressed in Fragile X syndrome patients by chromosome analysis. These results showed that antibody test was a fast and simple method, but the diagnostic power was "perpect" for males, whereas the results were less specific for females.r females.

• International Journal of Reliability and Applications
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• v.9 no.1
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• pp.71-78
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• 2008

Based on the goodness of fit approach, a new test is presented for testing exponentiality versus exponential better (worse) than used (EBU (EWU)) class of life distributions. The new test is much simpler to compute, asymptotically normal, enjoys good power and performs better than previous tests in terms of power and Pitman asymptotic efficiencies for several alternatives.

• Transactions of Materials Processing
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• v.22 no.2
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• pp.86-92
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• 2013

When stamping ultra-high-strength steel (UHSS), the phenomenon of galling, which corresponds to a transfer of material from the sheet to the tool surface, occurs because of the high contact pressure between tool and workpiece. Galling leads to increased friction, unstable interface conditions, scratches on the sheet and the tool surfaces and, eventually, premature tool surface failures. Therefore, a simple and accurate evaluation method for tool scratching is necessary for the selection of tool material and coating, as well as for a better optimization of process conditions such as blank holder force and die radius. In this study, the pin-on-disc (PODT) and pin-on-flat surface (POFST) tests are conducted to quantitatively evaluate scratch-related tool life for stamping of UHSS. The variation of the friction coefficient is used as an indicator of scratch resulted from galling. The U-channel ironing test (UCIT) is performed in order to validate the results of the friction tests. This study shows that the POFST test provides a good quantitative estimation of tool life based on the occurrence of scratch.

• Journal of Applied Reliability
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• v.15 no.4
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• pp.270-275
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• 2015

Purpose : UHMWPE (Ultra-high-molecular-weight-polyethylene) is one of the most widely used material in knife protection clothes because of high strength, elasticity, and light weight. The purpose of this study is to develop the accelerated life test method and predict the lifetime for the knife protection fabric composed by UHMWPE. Methods : In this study, degradation characteristics of UHMWPE fibers and knife protection fabric for cut resistance were evaluated under the hydrolysis and photo-degradation conditions. It was found out that the degradation rate of retained tensile strength was more significant in the photo-degradation than hydrolysis. Therefore, the failure time was determined as the time that the retained tensile strength in photo-degradation is less than 50%. Considering an acceleration factor for irradiance and exposure time, the lifetime was predicted from the calculated failure time. Results : As a result of the accelerated life test, the $B_{10}$ lifetime of knife protection fabric composed by UHMWPE fibers is estimated as 2.8 years for a 90% statistical confidence level. Conclusion: Since the lifetime is predicted by the view-point of radiant exposure in this study, there is a possibility that the estimated lifetime may differ from the actual lifetime. However, it is considered as an useful methodology to estimate the long-term lifetime of knife protection fabrics.

• The KSFM Journal of Fluid Machinery
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• v.19 no.3
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• pp.53-56
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• 2016

In this study, experiments and finite element method analysis were used to determine the autofrettage pressure that is optimal and then maximizes the cycling life of Type3 composite cylinders used in self-contained breathing apparatus. For both approaches, the cylinders were pressurized at 100, 110, ${\ldots}$, 290 % of the test pressure, respectively. The stresses were computed by the FEM analysis; while the strains of cylinders were recorded and the failure modes were monitored during the cycling test. As a result, from the good agreements between the simulations and experiments, it was concluded that at least 70 % of the test pressure should be applied as the autofrettage pressure in order to takes visible effect on the cycling life, and 160 % of the test pressure induces the maximum cycling life and the desired failure mode.

• The Journal of Korean Physical Therapy
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• v.33 no.2
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• pp.114-121
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• 2021

Purpose: This study examined the effects of therapeutic massage (TMP) and home exercise program (HEP) on pain, range of motion (ROM), depression, and quality of life (QOL) after arthroscopic rotator cuff repair in middle-aged women. Methods: Nineteen middle-aged women who underwent arthroscopic rotator cuff repair were enrolled in the study. All subjects were assigned randomly to the experimental group (n=9) or the control group (n=10). The subjects in both groups performed HEP for 30 minutes, three times per day, for eight weeks. The subjects in the experimental group also performed HEP, with TMP being performed for 30 minutes, 16 sessions for eight weeks. All subjects were evaluated with a visual analogue scale (VAS), shoulder ROM, self-rating depression scale (SDS), and Korean brief version of WHO quality of life scale (WHOQOL-BREF). A paired t-test was performed to test the significant differences between before and after the intervention. An independent t-test was conducted to test the significant differences between the groups. Results: Following the intervention, both groups showed significant differences than before the intervention in the VAS, shoulder ROM, SDS, and WHOQOL-BREF (p<0.05). There were significant differences in the ROM of shoulder flexion, SDS, and WHOQOL-BREF between the groups (p<0.05). Conclusion: These findings suggest that intensive TMP is an effective method for improving shoulder flexion mobility, depressive symptom, and QOL in middle-aged women after arthroscopic rotator cuff repair.

• Journal of Korean Public Health Nursing
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• v.19 no.2
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• pp.316-327
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• 2005

Purpose: This study intends to clarify the relative importance and character of the college student's attachment to their parents. We examined the effect that the father and mother attachments have en their self-efficacy and adjustment to their college life. Method: The subjects were 271 students who attendee a university. For this study, we used the inventory of the Parent Attachment-Revised version by Armsden and Greenberg, a self-efficacy test by Sherer et al. and the investigation far adjustment to college life by Barker & Siryk. The data were analyzed by t-test, ANOVA, Duncan test and simple multiple regression analysis on an SPSS WIN 10.0 program. Results: There was a significant differences in the attachment to the father according to their grades and in the attachment to the mother according to their type of residence. There was a significant difference in the adjustment to their college life according to their grades. Regression analysis on attachment and self-efficacy suggested that attachment has an influence on self-efficacy. Regression analysis on attachment and adjustment to college life suggested that attachment has influence on the adjustment to college life. Attachment also has an influence on academic adjustment, social adjustment, personal-emotional adjustment and institutional adjustment on the subscale of adjustment to college life. Regression analysis on self-efficacy and adjustment to college life suggested that self-efficacy has an influence on adjustment to college life. Further, self-efficacy has an influence on academic adjustment, social adjustment, personal-emotional adjustment and institutional adjustment on the subscale of adjustment to college life. Conclusion: This study shows that there are relationships among attachment, self-efficacy and adjustment to college life. Especially, self-efficacy is a very important factor influencing the adjustment to college life. So, a plan designed to increase students' self-efficacy should be created based on the results of this study.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.3 s.116
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• pp.66-71
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• 2006

The objective of this study was to find in what color Hanji(Korean hand-made paper) is dyed when it is dyed with a pigment extracted from clove tree using different kinds of mordant, and how the paper is discolored and variety of strength under the condition of accelerated aging test. The results of this experiment are as follows. The Hanji dyed with aluminum acetate mordant was colored yellowish brown at pH 4.82, discoloration after aging was as much as a slight difference of color was recognized, and the decrease of strength after aging test was small. Thus, the method using aluminum acetate mordant was usable in coloring Hanji. The second most useful Hanji dyeing moth of was using distilled water and ferrous sulfate mordant, which dyed Hanji light brown at pH 6.03. However, when pigment was extracted using distilled water and copper sulfate mordant was used, discoloration was satisfactory but strength decreased too much and pale brown was obtained. Thus, this method was not usable.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.4 s.117
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• pp.24-30
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• 2006

Formation which is an indicator of nonuniformity in fiber distribution is concerned with small scale variation in roughness, optical properties, print density, and so on. This study evaluated the formation of sheets which were made usning handsheet former and paper-machine with hydraulic headbox. Optical method and ${\beta}-ray$ method were used for formation test. The fiber type, freeness and basis weight of sheet were considered as variables. The formation of handsheet was affected by fiber type and freeness, and floe size distribution was influenced by basis weight. For machine made sheet, its formation seemed to be dependent on the hydraulic forces in headbox and former. When two formation test methods were compared, there was the highest relationship between optical formation index and normalized standard deviation from ${\beta}-ray$ method.