• Title/Summary/Keyword: covariance response

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On Securing Continuity of Long-Term Observational Eddy Flux Data: Field Intercomparison between Open- and Enclosed-Path Gas Analyzers (장기 관측 에디 플럭스 자료의 연속성 확보에 대하여: 개회로 및 봉폐회로 기체분석기의 야외 상호 비교)

  • Kang, Minseok;Kim, Joon;Yang, Hyunyoung;Lim, Jong-Hwan;Chun, Jung-Hwa;Moon, Minkyu
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.3
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    • pp.135-145
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    • 2019
  • Analysis of a long cycle or a trend of time series data based on a long-term observation would require comparability between data observed in the past and the present. In the present study, we proposed an approach to ensure the compatibility among the instruments used for the long-term observation, which would allow to secure continuity of the data. An open-path gas analyzer (Model LI-7500, LI-COR, Inc., USA) has been used for eddy covariance flux measurement in the Gwangneung deciduous forest for more than 10 years. The open-path gas analyzer was replaced by an enclosed-path gas analyzer (Model EC155, Campbell Scientific, Inc., USA) in July 2015. Before completely replacing the gas analyzer, the carbon dioxide ($CO_2$) and latent heat fluxes were collected using both gas analyzers simultaneously during a five-month period from August to December in 2015. It was found that the $CO_2$ fluxes were not significantly different between the gas analyzers under the condition that the daily mean temperature was higher than $0^{\circ}C$. However, the $CO_2$ flux measured by the open-path gas analyzer was negatively biased (from positive sign, i.e., carbon source, to 0 or negative sign, i.e., carbon neutral or sink) due to the instrument surface heating under the condition that the daily mean temperature was lower than $0^{\circ}C$. Despite applying the frequency response correction associated with tube attenuation of water vapor, the latent heat flux measured by the enclosed-path gas analyzer was on average 9% smaller than that measured by the open-path gas analyzer, which resulted in >20% difference of the sums over the study period. These results indicated that application of the additional air density correction would be needed due to the instrument heat and analysis of the long-term observational flux data would be facilitated by understanding the underestimation tendency of latent heat flux measurements by an enclosed-path gas analyzer.

Effects of gradual loaded exercise on antioxidative enzymes response in normal and obese men (비만인과 정상인간 일회성 점증부하 훈련이 항산화 효소에 미치는 효과)

  • Kim, Jin-Woo;Cho, Byung-Jun;Han, Gun-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.10
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    • pp.3820-3825
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    • 2010
  • The purpose of this study was to identify the effects of acute exercise on antioxidative enzymes in noramal and obese men. The written informed consent was obtained from 16 participants of eight normally healthy persons and eight obesity ones. The baseline level of obesity was determined at 25 % of the body fat. Any subjects had no experiences in participating in exercise and did not take vitamin or mineral supplement. Blood was sampled at five minutes before exercise, at exhaustion, and after 30 minutes of recovery. All statistical analyses and description methods were computed by SPSS window 14.0. Analysis of Covariance(ANCOVA) was performed to know the differences in values between pre- and post- exercise in each group. We found that after exhaustion, the normal group showed higher erythrocyte superoxide dismutase (SOD) activity compared to the obesity group. At exhaustion, the normal group had lower HSP activity compared to the obesity group. Based on the results, an acute exercise of normally healthy people induced an up-regulation of superoxide dismutase (SOD) activity. This plays an important role in the protection of extra-cellular fluid components against peroxide-mediated damage.

A Study on the Factors Affecting the Consumption of Coffee and Tea among Female in Seoul (여성의 커피와 다류의 섭취에 영향을 주는 요인에 관한 연구)

  • Sohn, Kyung-Hee;Lee, Min-June;Min, Sung-Hee;Lee, Hyun-Jou
    • Journal of the Korean Society of Food Culture
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    • v.15 no.5
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    • pp.398-412
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    • 2000
  • The purposes of this study are : (a) to investigate the attitude to various coffee and tea of women, (b) to analyze the characteristics of each classified group according to eating frequency, and (c) to abstract the factors which can influence the consumption of coffee and tea. Questionnaires were hand delivered to 1,200 women residing in Seoul. A total of 1012 was usable: resulting in 84% response rate. Statistical data analysis was completed using SAS Package program for the one way-analysis of variance(ANOVA), Duncan's multiple comparison test, factor analysis and analysis of covariance (ANOCOVA). (a) Instant coffee was most consumed(22.1 times a month), green tea in tea bag(8.7), Donggulre tea(8.3), Coffee (72) in order of frequency. Among Korean traditional tea Donggulre tea(8.3) and Yuja tea (2.0) were most prefered but still a minute quantity of Korean traditional tea was enjoyed. (b) Coffee and Black tea was regarded unhealthful but habitual, delicious and familiar beverage. Green tea was regarded good for health but not so habitual, practical and familiar. The consumer awareness can be grouped into 3 clases : Healthy factor, Habitual Practical factor, Familiar factor. (c) The sociodemographic characteristics of women influenced the beverage consumption. Women in their 30s and 40s consumed much of instant coffee and coffee. 10s and 20s consumed much of canned coffee. Working women drank much of instant coffee and green tea in tea bag. Women in highest income group$({\geq}\;4,000,000\;won/month)$ consumed much of coffee. (d) The factors which influenced the eating frquency of those beverages were various. The eating frequency of instant coffee was influenced by the age, familiar factor and habitual practical factor. And coffee were influenced by income level, habitual practical factor. The frequency of green tea in tea bag was influenced by habitual practical factor and familiar factor, green tea was influenced by healthy factor and habitual practical factor, Donggulre tea was influenced by habitual practical factor.

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Error analysis on factorization and the effect of online individualization classes (인수분해에 대한 오류 분석과 온라인 개별화 수업의 효과)

  • Choi, Dong-won;Heo, Haeja
    • Journal of the Korean School Mathematics Society
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    • v.24 no.1
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    • pp.83-105
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    • 2021
  • In this paper, we analyzed the misconceptions and errors incurred during factorization learning. We also examined whether online individualization classes had a positive effect on students' mathematical achievement. The experiment was conducted for 4 weeks (16 times in total) on middle school juniors in rural areas of Gyeonggi Province, where the influence of private extra education was small. In the class, the 'Google Classroom' was used as a LMS, the video lecture was uploaded to YouTube, and the teacher interacted with the students through "Zoom" and "Facetalk". In the online class situation, students' assignments and test answers were checked in real time through 'Google Classroom', and immediate feedback was provided to the experimental class group's students. However, for the control group students, feedback was provided only to those who desired. A total of 7 achievement evaluations were conducted in the order of pre-test, formative evaluation (5 times), and post-test to confirm the change in students' ability improvement and achievement. Through the formative evaluation analysis, it was possible to grasp the types of errors and misconceptions that occured during the factorization process. Students' errors were divided into four types: theorem or definition distortion error, functional errors such as calculation, operation, and manipulation, errors that do not verify the solution, and no response. As a result of ANCOVA, the two groups did not show any difference from the 1st to 4th formative assessment. However, the 5th formative assessment and post-test showed statistically significant differences, confirming that online individualization classes contributed to improvemed achievement.

Neural Bases of Empathy in Competitive vs. non-Competitive situation (경쟁과 비경쟁 상황에서 공감의 신경학적 기제)

  • Hwang, Su-Young;Yoon, Mi-Sun
    • Korean Journal of Cognitive Science
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    • v.27 no.3
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    • pp.441-467
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    • 2016
  • This fMRI study is aim to investigate effects of competitive environment in cognitive empathic process in human brain. Empathy is known as a crucial factor for human's adaptive behavior in aspects of social cognition and it is almost automatic process, on the other hand competitive situation is psychologically devastated environment to win someone for getting rewards. We hypnotized that reading and understanding of other person's mind are a specific characteristic related to survival evolutionarily, however competition would have an effect on the empathic cognitive process because of mechanisms of competition. To manipulate the competitive atmosphere, one researcher took a role of competitor against participants and they were instructed to get monetary rewards when their performance was better than a competitor. 21 participants(9 males and 12 females) performed to judge the emotional valence of the empathic task consisted of illustrated images with various situation could be experienced in real world as on $1^{st}$ person perspective in both competitive and non-competitive condition, and did same performance with objects stimulus in control condition. In order to examine the competition effects on empathic process,, hemodynamic response were obtained during fMRI session and the imaging data were analyzed to identify brain regions where responses to each condition across the two consecutive runs. Participants' reaction time in competitive condition was faster statistically significant than non-competitive one. Activation for competitive condition increased in the following areas: ACC, mPFC, SMG, thalamus extended caudate and Nacc, parahippocampal gyrus, and for non-competitive condition increased paracingulate gyrus, temporal pole, vmPFC, superior occipital gyrus. As a result of regression analysis using empathic scores as covariance, the rSMG, IFG, fusiform gyrus, thalamus, putamen were correlated with higher empathic levels, and TPJ were correlated with lower empathic scores. We suggest that these observations could mean competitive environment have an effect on neural base of cognitive empathic process.