• Journal of the Korean Society for Precision Engineering
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• v.24 no.2 s.191
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• pp.103-109
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• 2007

In fatigue life prediction, it is important that fatigue life is affected by crack closure phenomenon in thin sheet Al alloy. In this research, we attempt to (1)analyze the characteristics of fatigue crack propagation in constant loading condition for thin sheet Al 2024-T3 alloy which is generally used in transportation structures, (2)identify the crack closure phenomenon in thin sheet comparing experimental results of thin and thick sheet specimen under same fatigue loading condition. In using the fatigue related material constants from these fatigue crack propagation analysis, we attempt to (3)operate the fatigue life estimating process with considering crack closure phenomenon and (4)analyze the experimental and prediction results of fatigue life in thin sheet Al alloy.

• Journal of Applied Reliability
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• v.6 no.1
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• pp.37-50
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• 2006

The accelerated life tests of the catalytic gas sensor were performed at three different gas concentration conditions. From the test data, the power-Weibull model was estimated and the acceleration factor between test condition 25%LEL(Lowe Explosive Limit) and use condition 5%LEL was about 3 according to this acceleration model. Using this acceleration factor, life test specification for qualifying that B10 lifetime of the catalytic gas sensor meets the goal lifetime (5 years) was designed.

• Journal of the Korean housing association
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• v.19 no.4
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• pp.89-96
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• 2008

The environment has played a key role to improve the living condition and develop the industry. In building industries, we should consider the environment and mitigate the environmental affect. For mitigating the its affect, various areas of building technology have been developed and applied into filed work. In addition, the process in applying into field requires to conduct the assessment of the environmental affect and improve its applied technology. A lot of assessment methods are proposed in evaluate the building condition such as post-occupancy evaluation, life cycle management and life cycle assessment. Among these assessment methods, life cycle assessment is effectively utilized the environmental affect in building life cycle. Therefore, this paper aimed at analyzing the energy consumption and $CO_2$ emission in building life cycle, using the life cycle assessment and application of the example in apartment housing. This study shows that the maintenance and the production of building materials stage shares most of the amount of energy consumption and $CO_2$ emission and therefore plays an important role to planning the building in terms of the life cycle. Second, the other stages brings about a very small amount. It is important to decide the building shape and contents to mitigate the environmental affect in terms of material, volume, the pattern of the energy use and others.

• The Journal of the Korean life insurance medical association
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• v.2 no.1
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• pp.260-266
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• 1985

Pregancy is a part of women's life and is common process experienced by most women. On the other hand, a few cannot be pregnant. There are many reasons of infertility and myoma uteri of pelvic mass is a rare reason of infertility. Complication of pregnancy accompanied with myoma uteri is largely affected by the size or location of mass and the incidence by myoma uteri in pregnancy rarely happened, but mass with long pedunculus causes torsion as uterus is getting bigger. In labor myoma uteri causes the abnormal condition of fetal presentation and results in the abnormal childbirth. In case of myoma uteri, maternal mortality is low and there by medical hazards also decrease, but as the life insurance medical is the extensive prediction science, we believe that the prediction of perinatal or the condition of afterbirth by knowing the location, size of myoma uteri contributes to the medical examination. We experienced one case of Elderly primigravida with myoma uteri in Med Dept of Dae Han Kyouk life Insurance Co. Ltd. which the insured with medical examination believe herself as menopause. So we report the observations with studies.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.6
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• pp.653-659
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• 2015

The aim of this study is to develop a technique for the accelerated life test of the capacitor in a propulsion control device of a traction inverter used for a high-speed train. Using this technique, the accelerated life test can possibly estimate the life cycle of a capacitor under various temperature conditions and irregularly applied voltage. The accelerated life test is conducted for the capacitor of the traction inverter. The common proceedings of this test are selection of failure mechanism, determination of accelerated stress, range determination of the accelerated stress, determination of the test condition, and distribution and determination of the sample. From this result, the continuous applied voltage was not considered for the acceleration factors anymore. Therefore, the final result having an acceleration factor of 9.4 (= 13,626/1,445) was observed. Furthermore, the life-shortening acceleration effect for the irregular applied voltage condition can be applied to various situations.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.110-110
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• 2020

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.4
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• pp.126-132
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• 2010

Carbonation is the results of the interaction of carbon dioxide gas in the atmosphere with the alkaline hydroxides in the concrete. Reinforced steel corrosion due to concrete carbonation is one of main factors on the decrease in durability of RC structure. This study investigates the influence of carbonation on the bridges under various environment condition and quantifies the effect of carbonation various domestic field data. The failure probability of durability is evaluated on the basis of reliability concept. In addition, service life of the structures is predicted based on the intended probability of durable failure in domestic concrete specification. According to experimental results of the carbonation depth, the carbonation depth increased with structural age. It is analyzed that carbonation velocity of the structures under urban area and sea condition is 1.6-1.9 times faster than the river condition. Service life of the bridges under urban area and sea condition is decreased about 2.4-3.3 times than river condition.

• Food Science of Animal Resources
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• v.18 no.2
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• pp.115-124
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• 1998

This study was carried out investigate hygienic conditions of domestic packing plant for export and the shelf-life by Japanese standards. vacuum packaged chilled port loins provided by five packers(A, B, C, D and E) were transported to Japan in the same condition, Four packers(A, B, C adn d) produced the samples as hygienic as possible and one packer produced loins in the traditional hygienic condition, In TTC(2,3,5-triphenyl tetrazolium chloride) test all samples showed the negative reaction from the date of the quarantine(14 days after slaughtering) to 50 days The numbers of total plate count(TPC) of A, B, C and D packers that were below 108CFU/g until 50 days were accepted by Japanese Standards but TPC of E packer was over 107CFU/g at 30 days. VBN values increased sig-nificantly(P<0.01) in samples of A,B and D packers in the samples of C packer and E packer at 5% and 0.1% level respectively. The pH values of the vacuum packaged chilled pork for export at 14 days after slaughtering were 5.43∼6.00 In sensory evaluation, A, B, C and D packers which improved hygi-enic condition produced the products with good color and appearance. low drip until 40 days storage at $0^{\circ}C$ But as the storage time increase off-flavor occured at 40days in A and D packer and at 50days in B and C packer. In conclusion according to the above results of microbiological physicochemical and sensory evalution the edible periods of Korean vacuum package chilled porks may be estimated to 40∼50 days for the packers who improved hygienic condition and the shelf lives were calculated as 32∼40 days from edible period by a factor of 0.8(safety coefficient) while that of the pork from E packer which was produced in the traditional hygienic condition was estimated to 30 days after slaughtering at $0^{\circ}C$ Therefore the shelf-life of the pork of E packer would be only 24 days.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.166-169
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• 2004

A fatigue test was used to evaluate the fatigue life of an actual structure. The loaded state and the constraint condition of an actual structure must be same as the specimen in order to apply the test results to an actual structure by the specimen. The loaded state and constraint conditions can't be same as the specimen in the actual structure which is complicated. In order to reduce these differences, an actual structure test with a lot of frequencies is need to get a fatigue life curve. Therefore, ten sets of accelerated test units which attached unbalanced mass were composed in this study. Acceleration history about the vibration of an actual structure was acquired. Rainflow counting was used on acceleration history, and the life curve return formula was assumed. The return formula that damage satisfied `1' was acquired in a feedback process by the Miner's rule, which was the linear cumulative damage theory. A conservative fatigue life curve was determined with a return formula to have been presumed by each set. The fatigue life of regular rpm condition was calculated by these conservative fatigue life curves.

• Journal of Korean Academy of Nursing
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• v.30 no.3
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• pp.670-681
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• 2000

The purpose of this study was to identity the level of burden, social support and quality of life of the subjects. The subjects of this study were 68 mothers of nephrotic syndrome patients whose children were hospitalized in one pediatric ward of the University Hospital in Seoul. The data was collected using questionnaires, and the period of the data collection was from Nov. 15 to Dec. 31, 1999. The instruments used for this study were the Burden Measurement Instrument developed by Montgomery et. al(1985), social support measurement instrument designed Brandt an Weinert(1978) and Quality of life scale designed by Ro,Yoo JA(1988). The data analysis was done by SPSS, t-test, ANOVA and the Pearson correlation coefficient. The results of were as follows. 1. The level of burden showed a mean score of 54.47, the level of social support, a mean score of 86.00 and the level quality of life, a mean score of 140.20. 2. The level of burden differed according to mother's religion, patient's purpose for admission and perceived patient's condition by mothers. 3. The level of social support and the level of quality of life differed according to perceived patient's condition by mothers. 4. There was a negative correlation between burden and social support(r=-.348, p<.001). Also, burden was negatively related with quality of life(r=-3.97, p<.001). Social support was positively related with quality of life(r=.064, p<.001).