• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 추계학술대회 논문집
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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

• 대한수학교육학회지:수학교육학연구
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• 제20권1호
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• pp.73-84
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• 2010

학교수학에서 다루는 수학적 모델링의 일반적인 특성은 하나의 실제적인 문제를 해결하기 위하여 수학적 모델을 도입하고 이를 풀어서 실제적인 문제에 답을 제시하는 일회적인 경우가 많다. 그러나 실제적인 문제는 일회적인 모델링으로는 해결되지 않거나 그 해가 충분히 정밀하지 못한 경우가 있다. 본 연구는 여러 가지 변인을 가진 실제적인 문제를 해결하기 위해 수학적 모델을 구성할 경우, 구성한 수학적 모델의 해의 의미성을 분석해 보고 필요하면 더욱 정교한 해를 구할 수 있는 모델로 나아가는 수학적 모델링의 정교화 과정 모형을 구안하였다. 또한 그것을 수학교실에서 활용할 수 있는 수학적 모델링의 예를 제시함으로써 학교수학에서 수학적 모델링의 정교화를 다룰 수 있게 하였다.

• 항공우주시스템공학회지
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• 제10권1호
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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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• 제56권2호
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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.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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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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• 제16권11호
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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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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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.

• 동아시아식생활학회지
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• 제27권3호
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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.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제25권2호
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• pp.197-211
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• 2022

본 연구의 목적은 자연수 뺄셈의 실생활 맥락 문제 상황에서 '큰 수'와 '작은 수'의 제시 순서와 관련한 교수학적 의사결정의 관례에 대한 개선 방안을 모색하는 것이다. 이를 위하여 수학 교과 전문성을 가지고 있는 초등교사 30명을 대상으로 자연수 뺄셈의 실생활 문제 상황에 등장하는 크고 작은 두 수의 제시 순서와 뺄셈 상황에 대한 교수학적 인식을 조사하였다. 설문 조사를 통해 수집한 자료는 뺄셈의 문제 상황 유형을 분석 기준으로 활용하여 양적, 질적 분석을 하였다. 연구 결과, 뺄셈에 대한 학생들의 사고의 폭을 넓힐 수 있도록 실제 상황의 크고 작은 두 수의 제시 순서를 유지하는 뺄셈의 실생활 맥락 문제 상황을 활용하여 지도할 필요가 있다. 그리고 다양한 실생활 기반의 뺄셈 문제해결 학습이 이루어질 수 있도록 '큰 수'를 먼저, '작은 수'를 나중에 생각해야 하는 문제 상황으로 변형시키는 관례적인 교수학적 조치에 대한 제고가 필요하다. 이를 위해서는 자연수 뺄셈 지도 시 '큰 수'를 먼저, '작은 수'를 나중에 생각해야 하는 뺄셈 문제 상황뿐만 아니라 실생활에서 종종 등장하는 '작은 수'를 먼저, '큰 수'를 나중에 생각하게 되는 뺄셈의 실생활 맥락 문제 상황 도입에 대한 필요성을 교사가 인식하고 이에 대한 교수학적 견해를 갖출 수 있도록 수업 반성 및 연찬의 기회를 제공해야 할 것이다.

• 농촌지도와개발
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• 제16권4호
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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.