• Title/Summary/Keyword: History Effect

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Evaluation of coolant density history effect in RBMK type fuel modelling

  • Tonkunas, Aurimas;Pabarcius, Raimоndas;Slavickas, Andrius
    • Nuclear Engineering and Technology
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    • v.52 no.11
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    • pp.2415-2421
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    • 2020
  • The axial heterogeneous void distribution in a fuel channel is a relevant and important issue during nuclear reactor analysis for LWR, especially for boiling water channel-type reactors. Variation of the coolant density in fuel channel has an effect on the neutron spectrum that will in turn have an impact on the values of absolute reactivity, the void reactivity coefficient, and the fuel isotopic compositions during irradiation. This effect is referring to as the history effect in light water reactor calculations. As the void reactivity effect is positive in RBMK type reactors, the underestimation of water density heterogeneity in 3D reactor core numerical calculations could cause an uncertainty during assessment of safe operation of nuclear reactor. Thus, this issue is analysed with different cross-section libraries which were generated with WIMS8 code at different reference water densities. The libraries were applied in single fuel model of the nodal code of QUABOX-CUBBOX/HYCA. The thermohydraulic part of HYCA allowed to simulate axial water distribution along fuel assembly model and to estimate water density history effect for RBMK type fuel.

Preference of Brand History, Congruity between Country of Brand and Country of Manufacture in Accordance with Conspicuous Consumption (브랜드 역사, 브랜드 원산지와 제조원산지 일치여부, 과시적 소비성향에 따른 선호도 연구)

  • Song, Hae o Reum;Hwang, Sunjin
    • Journal of Fashion Business
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    • v.21 no.1
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    • pp.1-11
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    • 2017
  • This study investigated the effect of brand history, congruity between country of origin and conspicuous consumption of fashion brand, based on the evaluation of customers. The factorial design was constructed as a 3-way mixed design: 2(brand history: presented vs not presented) ${\times}$ 2(congruity between Country of Brand(COB) and Country of Manufacture (COM): congruent vs incongruent) ${\times}$ 2(conspicuous consumption: high vs low). A total of 302 men and women aged above 30 and living in Seoul or within the capital area, were enrolled as subjects. Of these, 26 insincere responses were excluded and a final total of 276 responses were used in the analysis. The statistical analysis included reliability analysis, three-way ANOVA, and simple interaction effect analysis with SPSS 18.0 statistics. Our results indicate that brand history, congruity between COB and COM, and conspicuous consumption had significant effect on the fashion brand preference of consumers. Furthermore, presenting the brand history resulted in higher brand preference. Second, the brand history and conspicuous consumption had a significant interaction effect on brand preference. Consumers with higher conspicuous consumption showed significantly higher brand preference than those with lower conspicuous consumption. Third, congruity between COB and COM and conspicuous consumption had a significant interaction effect on brand preference. However, when COB and COM were dissimilar no significant effect of conspicuous consumption on brand preference was observed.

For the Deconstruction of the History of Western Architecture as a Discourse - A Reflection on the Education of the Architectural History in Korea - (우리 서양건축사 교육의 반성 - 담론으로서 '서양건축사'를 해체하기 위하여 -)

  • Khang, Hyuk
    • Journal of architectural history
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    • v.20 no.6
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    • pp.57-76
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    • 2011
  • This study is on the pedagogical convention of architectural history in Korea, especially that of Western Architecture. Recent institutional change in architectural school in Korea has caused overall restructuring of academic program. In spite of extension in the field of history there was no progress of method and way of thinking. There is no change in the point of view to see the western architecture and its history as a unique and specialized phenomenon in the civilization of mankind. Because of no recognition about for what, for whom, and how to, and because of orientalism, the cultural position of western architectural history and its narrative was not asked. With the help of post-colonialism, de-constructivism and critical historiography this paper tries to show the fundamental premise of western architectural history as a myth and show its prejudice as not being justifiable. The background of the discourse there has been a representation effect with regard to knowledge as a power. we need to escape from this kind of cognitional frame With the analysis of the its premise and narrative we can find it is a historical construct that was made in the age of imperialism. In fact it has a lot of false information and problematic point of view. The Identity and originality of western architecture and its history has no logical reason or foundation if we think that it depends on the difference and comparison with other civilization. For example the explanation of its historical origin western architecture has big difference with Islamic architecture in spite of the resemblance each other. This paper try to show several reasons that discourse of western architectural history can not be survived any longer. So we need to reconstruct new pedagogy with deconstruction for the students of non western, or Korean students. Because it has important effect to see and think about architecture and its history.

A Study on Effect of Learner Centered Mathematical Club Based on Mathematics History (수학사 기반 학습자 중심 수학동아리 효과 분석 연구)

  • Boo, Deok Hoon
    • Journal for History of Mathematics
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    • v.28 no.1
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    • pp.45-62
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    • 2015
  • This study assumes alternative character of the operation of mathematical club in middle school. The case that operated the voluntary mathematics club for one year was analyzed and the educational effect was considered. First, the examination instrument for choosing the members of mathematics club was developed and used. And, diverse teaching and learning materials for improving creativity and mathematical ability of the members were used. Second, the difference of learning result between the experiment group and control one who joined the activities of mathematics club was analyzed. Finally, mathematical club activity based on mathematics history appeared to be effective in improving academic achievement and mathematics exploration activity.

Effect of Stress History on CPT-DMT Correlations in Granular Soil (응력이력이 사질토의 CPT-DMT 상관관계에 미치는 영향)

  • Lee, Moon-Joo;Choi, Sung-Kun;Kim, Min-Tae;Lee, Ju-Hyeong;Lee, Woo-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.730-739
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    • 2010
  • Stress history increases in penetration resistance due to the increase in residual horizontal stress of granular soil. This study analyzes the effect of stress history on the results of CPT and DMT from calibration chamber specimen in OC as well as NC state. Test results show that the normalized cone resistance by mean effective stress correlates well with the relative density and the state parameter, whereas the normalized cone resistance with regard to vertical effective stress is a little affected by stress history. The horizontal stress index($K_D$) in DMT more reflects the influence of stress history on granular soil than the dilatometer modulus($E_D$) and cone resistance($q_c$). The $K_D/K_0$, in which the effect of stress history on $K_D$ is compensated by the at-rest coefficient of earth pressure, $K_0$, is related to relative density, state parameter and the normalized cone resistance by mean effective stress. It is also observed that the normalized dilatometer modulus by mean effective stress($E_D/{\sigma_m}'$) is unique correlated with the state parameter, regardless of stress history.

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The Educational Effect of History Lessons on the Subject of Climate Change Regarding Environmental Awareness (기후 변화 주제를 다룬 역사 수업의 환경교육 효과)

  • Kim, Eun-Jeong;Yun, Sun-Jin
    • Hwankyungkyoyuk
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    • v.22 no.2
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    • pp.56-78
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    • 2009
  • Currently, climate change is regarded as one of the most important environmental issues in the 21st century. However, climate change education is not seriously carried out in schools. This study is concerned about enhancing students' recognition about climate change and actions responding to climate change through an history discipline. More specifically, this study tried to identify the effect of history lessons on environmental education, especially focused on climate change, by performing an experiment. The experiment was designed based on Solomon four-group design and carried out in one high school in Gwangmyeong city. Findings of the experiment are as follows. First, students who had taken the reorganized history lesson based on climate change - that is, students with experimental treatments - gained higher understanding of climate change than before and students of control groups. Second, students with experimental treatments gained higher understanding about relationship between history and climate change. Third, students with experimental treatments showed higher possibility of taking responding actions to climate change. In conclusion, history lessons reorganized with environmental issues, for instance climate change, have big potential for environmental education since they contribute to enhancing environmental recognition and prompting responding actions through exploration the effects of existing historical facts. Interdisciplinary approach like that taken in this study will provide students with more comprehensive and extended prism for the environment.

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Stability of Environmental Disposition Validated Through a Shout Term Education -The Effect of 'Interior Design History' Course on Students' Environmental Disposition- (단기교육 영향에 대한 실내환경적 성향의 안정성 규명연구 -'실내디자인 양식사' 수강경험이 실내환경적 성향에 미치는 영향-)

  • 이연숙;이선미;이경은;민지희
    • Korean Institute of Interior Design Journal
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    • no.20
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    • pp.3-9
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    • 1999
  • The purpose of this study was to verify the stability of environmental disposition through analyzing the short term effect of the 'Interior Design History' course on students environmental dispositions, especially their interior image preferences toward traditional/modern, female/masculine, and simple/complex characteristics. The pre-test post-test control group experimental design was used. The independent variable was the experience of the Interior Design History course, and the dependent variable was environmental disposition measured by IIPS(Interior Image Preference Scale). The measurements were done at both beginning and end of fall semester, 1997. Subjects were using 71 undergraduate students of Drafting course (control group) and 35 undergraduate students of Interior Design History course (experimental group) at Y University. Data were analyzed using frequency, percentage, mean, and F-test through ANOCOVA. This research revealed no effect of the Interior Design History course on students interior environmental dispositions. The stability of those environmental dispositions and also the validity of the IIPS were proved.

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A Study on Accuracy Improvement for Estimation of Vehicle Information Using BWIM Methodology (BWIM방법을 이용한 차량 정보 추정시 정밀도 향상 방안에 관한 연구)

  • Hwang, Hyo-Sang;Kyung, Kab-Soo;Lee, Hee-Hyun;Jeon, Jun-Chang
    • Journal of the Korean Society of Safety
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    • v.28 no.1
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    • pp.63-73
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    • 2013
  • Dynamic strain history curve measured in the field is influenced by various factors such as vehicle type, speed, noise, temperature and running location etc.. Because such curve is used for vehicle weight estimation methodology suggested by Moses, exact strain history curve is the most important thing for exact estimation of vehicle weight. In this paper, effect of such factors mentioned above is investigated on the measured strain history curves, and results of weight estimation of vehicles are discussed quantitatively. From this study, it was known that temperature effect contained in the strain history curve measured for long time in-site gives the biggest effect on result of weight estimation and it can be removed by using the mode value. Furthermore, gross vehicle weight can be estimated within 5% error corresponding to A class of the European classification if effects of temperature and noise are removed and vehicle properties such as speed, axle arrangement and running location are considered properly.

Reliability of Covariates in Baseline Survey of a Cohort Study: Epidemiological Investigation on Cancer Risk Among Residents Who Reside Near the Nuclear Power Plants in Korea (코호트 기반 조사 공변수 자료의 신뢰도 평가 연구: 원전주변지역주민 역학조사연구)

  • Bae, Sang-Hyuk;Park, Bo-Young;Li, Zhong-Min;Ahn, Yoon-Ok
    • Journal of Preventive Medicine and Public Health
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    • v.43 no.2
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    • pp.159-165
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    • 2010
  • Objectives: We evaluated the reliability of the possible covariates of the baseline survey data collected for the Epidemiological Investigation on Cancer Risk Among Residents Who Reside Near the Nuclear Power Plants in Korea. Methods: Follow-up surveys were conducted for 477 participants of the cohort at less than 1 year after the initial survey. The mean interval between the initial and follow-up surveys was 282.5 days. Possible covariates were identified by analyzing the correlations with the exposure variable and associations with the outcome variables for all the variables. Logistic regression analysis with stepwise selection was further conducted among the possible covariates to select variables that have covariance with other variables. We considered that these variables can be representing other variables. Seven variables for the males and 3 variables for the females, which had covariance with other possible covariates, were selected as representative variables. The Kappa index of each variable was calculated. Results: For the males, the Kappa indexes were as follow; family history of cancer was 0.64, family history of liver diseases in parents and siblings was 0.56, family history of hypertension in parents and siblings was 0.51, family history of liver diseases was 0.50, family history of hypertension was 0.44, a history of chronic liver diseases was 0.53 and history of pulmonary tuberculosis was 0.36. For females, the Kappa indexes were as follow; family history of cancer was 0.58, family history of hypertension in parents and siblings was 0.56 and family history of hypertension was 0.47. Conclusions: Most of the possible covariates showed good to moderate agreement.

Predictive Effects of Previous Fall History on Accuracy of Fall Risk Assessment Tool in Acute Care Settings (기존 낙상위험 사정 도구의 낙상 과거력 변인 효과)

  • Park, Ihn Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.19 no.4
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    • pp.444-452
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    • 2012
  • Purpose: To explore the usefulness of previous fall history as a triage variable for inpatients. Methods: Medical records of 21,382 patients, admitted to medical units of one tertiary hospital, were analyzed retrospectively. Inpatient falls were identified from the hospital's self-report system. Non-falls in 1,125 patients were selected by a stratified matching sampling with 125 patients with falls (0.59%). A comparative and predictive accuracy analysis was conducted to describe differences between the two groups with and without a history of falls. Logistic regression was used to measure the effect size of the fall history. Results: The fall history group showed higher prevalence by 9 fold than the non-fall history group. The relationships between falls and relevant variables which were significant in the non-fall history group, were not significant for the fall history group. Falls in the fall history group were 25 times more likely than in the non-fall group. Predictive accuracy of the risk assessment tool showed almost zero specificity in the fall history group. Conclusion: The presence of fall history, the fall prevalence, variables relevant to falls, and the accuracy of the risk tool were different, which support the usefulness of the fall history as a triage variable.