• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.1
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• pp.125-133
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• 2012

This study aims at structural analysis with fatigue on the shock absorber mount of automobile. Two kinds of mount as original model 1 and reinforced model 2 are applied. Among the cases of nonuniform fatigue loads at both models, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'SAE bracket history' or 'SAE transmission', the maximum fatigue life at model 2 is 5 to 6 times as much as model 1 and the minimum damage at model 2 is decreased 5 to 6 times as much as model 1. In case of 'Sample history' as slow fatigue loading history, the minimum damage at model 2 becomes same as model 1 but the maximum fatigue life at model 2 is decreased more than 17 times as much as model 1. In case of 'Sample History' with the average stress of -$10^4MPa$ to $10^4MPa$ and the amplitude stress of 0MPa to $10^4MPa$, the possibility of maximum damage becomes 3%. This stress state can be shown with 5 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. Safe and durable design of shock absorber can be effectively improved by using this study result on mount frame.

• Korean Journal of Social Welfare
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• v.65 no.1
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• pp.83-107
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• 2013

The purpose of this study is to understand the life experiences of an adult adoptee. For this purpose, the data were collected through in-depth interviews with an adult adoptee, observation, and documents and analyzed using life history approach. Results of analysis were composed of summarized life history, thick description of life history, theme analysis, and issues for intervention. The themes generated from analysis are 'a slub', 'a larva that want to be a butterfly', 'I am okay. No, I am not okay', 'because it is not my fault', 'love, the critical determinant leading my life'. Researchers, also, examined intervention issues of adoption, post-adoption service, closed adoption or open adoption, searching root, intervention for adult adoptee. Based on the results of this study, the policies and practical guidelines for adult adoptees were suggested.

• Journal of Korean Society of Steel Construction
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• v.8 no.4 s.29
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• pp.19-29
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• 1996

In this paper, it is presumed that the stress time history was generated by simulation method and investigated compatibility in regard to the reappearance of stress time history. In this procedure, the identified frequency distribution of stress range of the steel railroad bridge varies with the rational values of cut off point and bar width. Thus, we show variable aspect of the equivalent stress range results from change of cut off point and bar width. In addition, we analyze the variable of RMC and RMS model due to the cut off point and bar width of the measured stress history which influencs the prediction of fatigue life in the steel railroad bridge. The simulated stress time history is carried out by the superposition method incorporating the vertical load with rotation moment obtained from the Hermition interpolation function, and compared with developing stress results from measured maxi mum stress. Through this study, we can estimate the remaining fatigue life from a safety point of view and comparative accuracy.

• Ocean and Polar Research
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• v.34 no.3
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• pp.275-286
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• 2012

Over the last 20 years there have been more than 3000 peer-reviewed papers relating to climate change and biodiversity published, and still the numbers are increasing. However, most studies focused on the impacts of climate change at population or community levels, and the results invariably reveal that there has been, or will be, a negative effect on the structure and pattern of biodiversity. Moreover, the climate change models and statistical analyses used to test the impacts are only newly developed, and the analyses or predictions can often be misled. In this review, I ask why an individual's life history is considered in the study how climate change affects biodiversity, and what ecological factors are impacted by climate change. Using evidence from a range of species, I demonstrate that diverse life history traits, such as early growth rate, migration/foraging behaviour and lifespan, can be shifted by climate change at individual level. Particularly I discuss that the optimal decision under unknown circumstance (climate change) would be the reduction of the ecological fitness at individual level, and hence, a shift in the balance of the ecosystem could be affected without having a critical impact on any one species. To conclude, I summarize the links between climate changes, ecological decision in life history, the revised consequence at individual level, and discuss how the finely-balanced relationship affects biodiversity and population structure.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.120-139
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• 2017

The purpose of this research was to explore life history of an elderly woman who fled from North Korea and to understand and provide interventions for female North Korean Defector. The participant of this research is an 81-year-old woman who escaped from North Korea and has lived in South Korea for over 14 years. This life history study followed the analysis of Mandel baum(1973) pointing three perspectives of life: dimensions, turnings, and adaptations. This study concluded that the participant of the research study had no protection while staying in China and North Korea and had experience of Homo Sacer. And even after arriving to South Korea the participant had to live her life with the past negative experiences in North Korea and China. Based on the research results discussions and implications were suggested.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.319-324
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• 2007

To investigate the impacts of transgenic rice on freshwater organisms, we conducted two life table experiments using Daphnia magna for fifteen and twenty days, respectively. We examined life history traits such as population growth rates (r), reproductive rates ($R_0$), generation times, and survivorship. In the first experiment, we used non-drought-stressed transgenic and non-transgenic rice harvested in 2005. In the second study, we used non-transgenic and transgenic rice harvested in 2006 following drought stress. Each experiment involved three treatments in which D. magna neonates were fed with Selenastrum capricornutum (control treatment) and S. capricornutum with 5% aqueous extracts of non-transgenic rice (N-T) and transgenic rice (T). In the first experiment, D. magna showed reduced population growth rates and lowered fecundity in the N-T and T treatments. In the second experiment, D. magna receiving both transgenic and non-transgenic rice extracts showed very high mortality, low population growth rates and reproduction rates. We could not detect any significant negative effects of extracts from transgenic rice on D. magna life history traits at 95%.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.997-1002
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• 2007

A guideway vehicle is used in automobile, semiconductor and LCD manufacturing industries to transport products efficiently. Since the operating speed of the guideway vehicle should be increased for maximum productivity, the weight of the vehicle has to be reduced. This may cause parts in the system to fail before the life of the system. Therefore estimation of the fatigue life of the parts becomes an important problem. In this study, the fatigue life of the driving wheel in the guideway vehicle is estimated using a S-N curve. To obtain the fatigue life of a part, the S-N curve, load time history applied on a driving wheel and material property are required. The S-N curve of the driving wheel is obtained using the fatigue experiment on wheels. Load time history of the wheel is obtained from multibody dynamics analysis. To obtain the material properties of the driving wheel, which is composed of aluminum with urethane coating, a compression hardware testing has been done with the static analysis of the FE model. The fatigue life prediction using computational analysis model guarantees the safety of the vehicle at the design stage of the product.

• Journal of KSNVE
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• v.10 no.4
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• pp.686-691
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• 2000

In this paper a computer aided analysis method is proposed for durability assessment in the early design stages using dynamic analysis, stress analysis and fatigue life prediction method. From dynamic analysis of a vehicle suspension system, dynamic load time histories of a suspension component are calculated. From the dynamic load time histories and the stress of the suspension component, a dynamic stress time history at the critical location is produced using the superposition principle. Using linear damage law and cycle counting method, fatigue life cycle is calculated. The predicted fatigue life cycle is verified by experimental durability tests.

• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.210-226
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• 2018

This study was to explore the life history of an elderly woman who had six times of imprisonment and entered a Samchung re-education camp. This study of life history followed the analysis of Mandelbaum(1973) pointing three perspectives of life: dimensions, turnings, and adaptations. Participant's dimensions of life were exploitation of labor, hostess life for U.S. military, prison life, Samchung re-education camp, marriage with the disabled, life of a farm worker. Turnings of life were serving as a maid, confinement of prison, life of hostess for living, being remanded to Samchung re-education camp by state violence, marriage and divorce, denial of social welfare service. Adaptations of life were downright adaptation in early life, exaggerated act in juvenile reformatory, prostituted women as a simple fortune-maker, adaption as a good wife and wise mother after marriage, resistive adaption as a self-employed. and farm worker. Based upon this results outcome, discussions and implications were suggested.

• The Korean Journal of Archival Studies
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• no.80
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• pp.129-165
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• 2024

This study aims to emphasize the importance and activation of citizen oral history. As is well known, research on oral history gradually began in earnest in Korea from the 1980s. Until now, citizen interviews by researchers and elite interviews by researchers have steadily increased in quantity. However, citizen interviews by citizens are insignificant. The "Digital Life-history Archiving" project, which has been under the supervision of the Ministry of Culture, Sports and Tourism since 2021, is a new and meaningful attempt. Citizens are educated on archiving and oral history to conduct interviews and produce archives. It is producing high-quality oral archives, securing citizens' archiving capabilities, and building local cultural resources. Based on the experience of participating in this project in 2021, I evaluated the performance and limitations and looked at the implications. I expect it to help reduce trial and error in the future. I also proposed a plan to actively produce and utilize citizen oral archives. To this end, specific cooperation between oral-history institutions and oral archives platforms were also proposed.