• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.258-263
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• 2001

In this paper, the real-time prediction of high temperature creep life was carried out for the friction welded joints of dissimilar heat resistintg steels (CulCr0.5Zr-STS316L). Various life prediction methods such as LMP (Larson-Miller Parameter) and ISM (initial strain method) were applied. The creep behaviors of those steels and the welds under static load were examined by ISM combined with LMP at 300, 400 and 50$0^{\circ}C$, and the relationship between these two methods was investigated. A real-time creep life (tsub/r/, hr) prediction equation by initial strain ($\varepsilon_0$, %) under any creep stress ($\sigma$, MP$\alpha$) at any high temperature (T, K) was developed

• Journal of Educational Research in Mathematics
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• v.20 no.1
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• pp.73-84
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• 2010

Mathematical modeling is an important part of mathematics education since it can be used or created to find mathematical models to understand real life various situations. Most of mathematical modeling tasks taught and learned currently in secondary school mathematics classes need simple mathematical modelling with one or two variables and produce fixed solutions to the real life problems. But many real life problems involve various and complex variables which can be used to get more proper solutions. Constructing mathematical models to get more appropriate solutions from the real problems having various and complex variables is not easy. In this paper the researcher suggested a model to fit mathematical models to get more appropriate solutions and showed three examples to apply the model in solving real life problems which can be treated in the secondary school mathematics classrooms.

• Journal of Aerospace System Engineering
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• v.10 no.1
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• pp.51-58
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• 2016

In this paper, we present some results on No-failure accelerated life test of aerial vehicle for reliability demonstration. The design of general accelerated life test consists of the three phases: 1) Estimating normal life test time of a single product from Weibull distribution model; 2) Determining the acceleration factor (AF) by utilizing the relation between the life of mechanical components and the applied torque; 3) Calculating the accelerated life test time, which comes from dividing the estimated normal life test time into AF. Then, we applied the calculated life test time to the real reliability test of the flap actuating system, while considering the requirement specification for mechanical components and operating environment of the actuation system. Real experimental processes and results are presented to validate the theory.

• Structural Engineering and Mechanics
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• v.56 no.2
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• pp.201-221
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• 2015

The fatigue damage problems are frequently encountered in the design of civil engineering structures. A realistic and accurate fatigue life prediction is quite essential to ensure the safety of engineering design. However, constructing a reliable fatigue life prediction model can be quite challenging. The use of traditional deterministic approach in predicting the fatigue life is sometimes too dangerous in the real practical designs as the method itself contains a wide range of uncertain factors. In this paper, a new fatigue life prediction method is going to be proposed where the residual strength is been utilized. Several cumulative damage models, capable of predicting the fatigue life of a structural element, are considered. Based on Miner's rule, a randomized approach is developed from a deterministic equation. The residual strength is used in a one to one transformation methodology which is used for the derivation of the fatigue life. To arrive at more robust results, fuzzy sets are introduced to model the parameter uncertainties. This leads to a convoluted fuzzy based fatigue life prediction model. The developed model is illustrated in an example analysis. The calculated results are compared with real experimental data. The applicability of this approach for a required reliability level is also discussed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1691-1694
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• 2005

The fatigue characteristic of a material or a structure is derived from fatigue tests of standard specimens. However test results of standard specimens are very different from those of real structures or components. Therefore, to calculate more accurate fatigue life, the geometrical effect and surface condition must be considered by comparing test results of standard specimens with those of real structures or components. Thus the object of this paper is to evaluate the fatigue characteristic of a real waterwork pipe by conducting fatigue tests with standard specimens and non-standard(plate-shaped) specimens of base metal and weld metal. Also, to evaluate fatigue characteristic based on life distribution, statistical fatigue characteristic was analyzed by the normal distribution and related data of P-S-N curve.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1778-1783
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• 2006

Event-specific PCR detection methods are the primary trend in genetically modified (GM) plant detection owing to their high specificity based on the flanking sequence of the exogenous integrant. Therefore, this study describes a real-time PCR system for event-specific GM canola GT73, consisting of a set of primers, TaqMan probe, and single target standard plasmid. For the specific detection of GT73 canola, the 3'-integration junction sequence between the host plant DNA and the integrated specific border was targeted. To validate the proposed method, test samples of 0, 1, 3, 5, and 10% GT73 canola were quantified. The method was also assayed with 15 different plants, and no amplification signal was observed in a real-time PCR assay with any of the species tested, other than GT73 canola.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.161-163
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• 2012

Recently on Value Engineering(VE) and Life Cycle Cost(LCC) social interests is increasing. The government Turn Key, BTL projects and public works projects, such as VE and LCC Analysis on the value and economic analysis is mandatory. And accordingly the VE and LCC analysis is underway for the various studies. However, there is a problem existing in the LCC analysis. Worth the cost varies according to the flow of time. However, the real interest rate during the LCC analysis of buildings in calculation time for interest rates and inflation are not considering the value of the flow. In other words, a few years using the average value of the deterministic analysis method has been adopted. These costs for the definitive analysis of the cost of an uncertain future, unforeseen changes resulting hazardous value. In this study of the last 15 years interest rates and inflation targeting by using Monte-Carlo Simulation is to perform probabilistic analysis. This potential to overcome uncertainties of the cost of building a more scientific and LCC Estimation of the probability value of the real interest rate is presented.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.3
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• pp.268-279
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• 2017

The purpose of this study was to analyze the effects of dietary life application according to preferred dietary life education type on quality of life of participants in dietary life education programs and to provide basic data necessary to enhance dietary life education. The results of the analyses conducted to classify the types of preferred dietary life education and types of dietary life application and to verify the validity and reliability of the factors are as follows. In terms of the types of preferred dietary life education, health-oriented type, knowledge-oriented type, and experience-oriented type were derived. In terms of types of dietary life application, proactive application and emotional application were derived. Knowledge-oriented type and experience-oriented type were found to affect proactive application and emotional application in terms of real-life application, and proactive application and emotional application were found to affect quality of life. Therefore, in order to enhance the dietary life education for adults in general, it is necessary to improve accessibility by initiating and promoting various programs along with continuous support from central and local governments. Moreover, in order to increase the real-life application and utilization of such programs, the importance of practical and theoretical education must be recognized, and efforts should be made in training specialized instructors.

• Education of Primary School Mathematics
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• v.25 no.2
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• pp.197-211
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• 2022

In this study, we tried to find a way to improve the pedagogical decision-making practices related to the presentation order of 'large number' and 'small number' in problem situations of subtraction of the natural number. For this purpose, the elementary school teachers' perception about problem situations in real-life context of subtraction of natural numbers was investigated, and the collected data were analyzed qualitatively and quantitatively to identify teachers' pedagogical perceptions. As a result of this study, it was confirmed the need for consideration on how to set up a problem situations in real-life context of subtraction so that students can develop their ability to solve various types of problems. To this end, not only in a problem situation of subtraction where you have to think of 'large number' first and 'small number' later, but also about the introduction of problem situations in real-life context of subtraction in which you think about 'small number' first and 'large number' later, which often appears in real-life. You will need to recognize the need. And you should have a pedagogical view on this. The results of this study will be able to contribute to the preparation of pedagogical method that can expand the understanding of various problem situations where subtraction is applied from the lower grades of elementary school.

• Journal of Agricultural Extension & Community Development
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• v.16 no.4
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• pp.1021-1048
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• 2009

Based on Rural living indicator -2005 survey data, in RDA this study attempted to investigate Rural Residents' real life satisfaction or identity model by the types of leisure consumption depending on each generation and explored the relationship between leisure consumption and the enhancement of self-identity/ interpersonal relationship, and that between leisure consumption satisfaction and real life satisfaction. Based on systematic random sampling with constructed questionnaires, 1,870 data were collected and analyzed. Overall, the results of this study showed that there are statistically significant differences between generation in leisure consumption. In detail, the findings of this study are as follows. The types of Rural Residents' leisure consumption can be divided into three styles including Semi-leisure type, Passive leisure type and Total leisure type consumption. The preferred types of leisure consumption of Rural Residents' were Semi-leisure type, Passive leisure type and Total leisure type in order. Except for times-pending leisure culture consumption, Semi-leisure type and Passive leisure type influenced on the enhancement of self-identity and interpersonal relationship, then the enhancement of self-identity and interpersonal relationship influenced on leisure consumption-satisfaction, and finally leisure consumption satisfaction influenced on real life satisfaction.