• Title/Summary/Keyword: within-condition

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Identification of indirect effects in the two-condition within-subject mediation model and its implementation using SEM

  • Eujin Park;Changsoon Park
    • Communications for Statistical Applications and Methods
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    • v.30 no.6
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    • pp.631-652
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    • 2023
  • In the two-condition within-subject mediation design, pairs of variables such as mediator and outcome are observed under two treatment conditions. The main objective of the design is to investigate the indirect effects of the condition difference (sum) on the outcome difference (sum) through the mediator difference (sum) for comparison of two treatment conditions. The natural condition variables mean the original variables, while the rotated condition variables mean the difference and the sum of two natural variables. The outcome difference (sum) is expressed as a linear model regressed on two natural (rotated) mediators as a parallel two-mediator design in two condition approaches: the natural condition approach uses regressors as the natural condition variables, while the rotated condition approach uses regressors as the rotated condition variables. In each condition approach, the total indirect effect on the outcome difference (sum) can be expressed as the sum of two individual indirect effects: within- and cross-condition indirect effects. The total indirect effects on the outcome difference (sum) for both condition approaches are the same. The invariance of the total indirect effect makes it possible to analyze the nature of two pairs of individual indirect effects induced from the natural conditions and the rotated conditions. The two-condition within-subject design is extended to the addition of a between-subject moderator. Probing of the conditional indirect effects given the moderator values is implemented by plotting the bootstrap confidence intervals of indirect effects against the moderator values. The expected indirect effect with respect to the moderator is derived to provide the overall effect of moderator on the indirect effect. The model coefficients are estimated by the structural equation modeling approach and their statistical significance is tested using the bias-corrected bootstrap confidence intervals. All procedures are evaluated using function lavaan() of package {lavaan} in R.

Heat/Mass Transfer and Flow Characteristics Within a Film Cooling Hole of Square Cross Sections (II) - Effects of Asymmetric Inlet Flow Condition - (정사각 막냉각홀 내부에서의 열/물질전달 및 유동 특성 (II) - 비대칭 입구조건 효과 -)

  • Rhee, Dong-Ho;Kang, Seung-Goo;Cho, Hyung-Hee
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.7
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    • pp.937-944
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    • 2002
  • An experimental study has been conducted to investigate the heat/mass transfer characteristics within a square film cooling hole with asymmetric inlet now condition. The asymmetric inlet now condition is achieved by making distances between side walls of the secondary now duct and the film cooling hole different; one side wall is $2D_h$ apart from the center of the film cooling hole, while the other side wall is $1.5D_h$ apart from the center of the film cooling hole. The heat/mass transfer experiments for this study have been performed using a naphthalene sublimation method and the now field has been analyzed by numerical calculation using a commercial code. Swirl now is generated at the inlet region and the heat/mass transfer pattem with the asymmetric inlet now condition is changed significantly from that with the symmetric condition. In the exit region, the effect of mainstream on the inside hole now is reduced with the asymmetric condition. The average heat/mass transfer coefficient is higher than that with the symmetric condition due to the swirl now generated by the asymmetric inlet condition.

Relationship between dental caries and oral health behavior in middle and high school students: The Ninth(2013) Korean Youth Risk Behavior Web-based Survey (중·고생의 치아우식증과 구강건강행태와의 관련성 연구: 제9차(2013년) 청소년 건강행태 온라인 조사)

  • Lee, Jong-Hwa;Baek, Ji-Min;Yoo, Jin-Yeong
    • Journal of Korean society of Dental Hygiene
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    • v.15 no.1
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    • pp.119-127
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    • 2015
  • Objectives: The purpose of the study is to investigate the relationship between dental caries and oral health behaviors in middle and high school students by web-based survey of the ninth(2013) Korean youth risk behavior. Methods: The subjects were 75,149 students from 400 middle schools and 400 high schools. Finally, the survey participation rate was 96.4%(72,435 students from 799 schools) by complex sample design. The questionnaire consisted of general characteristics of the subjects, oral health behaviors, and oral health status. General characteristics included gender, types of schools, economic condition, and residential types. Oral health behaviors included subjective oral health condition, frequency of tooth brushing, tooth brushing after meal within recent 7 days, sealant within 12 months, fluoride application within 12 months, scaling within 12 months, and oral health education experience within 12 months. Oral health condition included dental caries incidence within 12 months. Results: Oral health behavior influenced on dental caries in the middle and high school students in Korea. This study showed the relationship between the sociodemographic characteristics, tooth brushing frequency, sealant experience, dental caries and halitosis experience, and scaling within 12 months. Scaling is the best prevention method for dental caries and halitosis in the students. Conclusions: The study showed the necessity for practical oral health education and the effect of fluoride application for dental caries prevention.

Heat/Mass Transfer and Flow Characteristics within a Film Cooling Hole of Square Cross Sections with Asymmetric Inlet Flow Condition (비대칭 입구조건을 갖는 정사각 막냉각홀 내부에서의 열/물질전달 및 유동 특성)

  • Rhee, Dong-Ho;Kang, Seung-Goo;Cho, Hyung-Hee
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.14-21
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    • 2001
  • An experimental study has been conducted to investigate the heat/mass transfer characteristics within a square film cooling hole with asymmetric inlet flow conditions. The asymmetric inlet flow condition is achieved by making distances between side walls of secondary flow duct and film cooling hole different; one side wall is $2D_h$ apart from the center of film cooling hole, while the other side wall is $1.5D_h$ apart from the center of film cooling hole. The heat/mass transfer experiments for this study have been performed using a naphthalene sublimation method and the flow field has been analyzed by numerical calculation using a commercial code. Swirl flow is generated at the inlet region and the heat/mass transfer pattern with the asymmetric inlet flow condition is changed significantly from that with the symmetric condition. At the exit region, the effect of mainstream on the inside hole flow is reduced with asymmetric condition. The average heat/mass transfer coefficient is higher than that with the symmetric condition due to the swirl flow generated by the asymmetric inlet condition.

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The Cortical representation in Korean-English picture naming: fMRI study (한국어-영어 그림 명명 시 나타나는 대뇌 영역: fMRI 연구)

  • Choi Wonil;Cho Kyungdnk;Nam Kichun
    • Proceedings of the KSPS conference
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    • 2003.05a
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    • pp.93-96
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    • 2003
  • The present study was conducted to investigate the difference of cortical activation in naming the picture in Korean and English. Experimental design was 2(Korean, English) language condition x 4(no distractor, semantic related distractor, semantic unrelated distrator, corresponding distractor) distractor condition. language condition was between subject factor and distractor condition was within subject factor. The result was that Korean naming condition showed less cortical activation than English naming condition. The activation region was reported in each condition.

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Mercury-Induced Light-Dependent Alterations of Chlorophyll a Fluorescence Kinetics in Barley Leaves

  • Lee, Choon-Hwan
    • Journal of Plant Biology
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    • v.38 no.1
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    • pp.11-18
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    • 1995
  • Mercury-induced changes in Chl a fluorescence induction kinetics of scratched barley leaf segments were dependent on the presence of light. By the treatment of 50$\mu$M HgCl2 under light condition, Fm and Fp were decreased. However, they were not significantly reduced under dark condition even after 2 h of mercury treatment. Under dark condition the decrease in variable fluorescence (Fv) after P transient was blocked within 20 min of the treatment. The analysis of fast fluorescence rise curve suggests that the inhibitory site of mercury under both light and dark conditions is not at QB binding site and the inhibition does not involve the increase in inactive PSII centers. Under light condition the decrease in Fp was partially recovered by addition of 50 $\mu$M NH2OH. These results suggest that a major inhibitory site of mercury under dark condition is at the reducing side of PSII and the site under light condition is at the oxidizing side of PSII possibly in addition to the one under dark condition. Under both light and dark conditions, energy-dependent quenching(qE) was alomost completely repressed within 20 min of mercury treatment and noticible change in Fo was not observed. The qE repression is probably due to the blockage of transthylakoid ΔpH formation.

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The Effect of Retrieval Difficulty and Association Strength on Memory Inhibition (자극의 인출난이도와 연합강도가 기억억제에 미치는 효과)

  • Yoonjae Jung
    • Korean Journal of Cognitive Science
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    • v.34 no.1
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    • pp.21-38
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    • 2023
  • The present study was designed to investigate the effect of the difficulty level of retrieval practice and the association strength of categories and stimuli within categories on memory inhibition. Most of the studies have investigated whether inhibition was occurred by manipulating the degree of association strength, emotion value or physical characteristics of non-retrieval practice words within the retrieval practice category. Therefore, it was necessary to study how inhibition occurs according to the degree of difficulty of retrieval stimuli during retrieval practice. The difficulty of retrieval was manipulated into three levels: difficult condition, normal condition, and easy condition through the degree of presentation of consonants and vowels of words during retrieval learning. Additionally, the strength of association between categories and words within categories was manipulated. In previous studies, retrieval-induced forgetting occurred under conditions where the association strength between categories and words within the categories was strong. On the other hand, retrieval-induced forgetting did not occur under conditions where the association strength between categories and words within the categories was weak. The present study, if the inhibition process differs according to the difficulty of retrieval, the possibility of different results from previous studies was explored according to the difference in the strength of association with the category. As a result of the study, in the condition of strong association strength, retrieval-induced forgetting was observed under normal and difficult retrieval difficulty conditions. Whereas retrieval-induced forgetting was not observed under conditions of easy retrieval difficulty condition. In the condition of weak association strength, retrieval-induced forgetting tended to occur under difficult retrieval difficulty conditions. Whereas retrieval-induced forgetting was not observed under conditions of normal and easy retrieval difficulty condition. These results suggest that memory inhibition may appear differently depending on the difficulty of retrieval.

Control of Hydrocracking Temperature in Ebulated Recycle Reactor (유동화 재순환 반응기에서 석유의 수소첨가 반응시 이탈된 온도제어)

  • 이창우;홍영호;함영민
    • Journal of the Korean Society of Safety
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    • v.13 no.2
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    • pp.76-87
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    • 1998
  • This study was carried out to investigate the effect of on temperature control from actuating method, recycling ratio and the position (top, middle and bottom) of set and controlled temperature within the reactor in adiabatic ebullated recycling condition, when the disturbance was occurred. Estimation of the solution were performed numerically using the finite difference method. It was assumed that the reaction is in constant with heat of reaction and the physical properties(density, heat capacity and viscosity, etc) of the reactants are same condition within the reactor.

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Effect of Kinetically Processing Conditions on Ink Transfer Ratio for Transfer Printing

  • Park, Sung-Ryool;Kim, Se-Min;Ryu, Gi-Seong;Lee, Chang-Bin;Song, Chung-Kun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.910-913
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    • 2009
  • This paper examines attaching speed, detaching speed and contact time which affected in the ink transfer ratio and presents the best conditions for fabrication process of electrodes with Ag-ink using microcontact printing method. In conclusion, it shows the best printing characteristic by two conditions. One of condition is the attaching speed have to within less than 1mm/s and the detaching speed is high velocity as 1000mm/s and the contact time is taken about the minimum time when inking process. Another condition is the attaching speed have to within more than 100mm/s and the detaching speed have to within less than 1mm/s and the contact time is longer than 30second when the printing process. As using these condition and the stamp sized 5cm${\times}$5cm, it was possible for printing equally until $30{\mu}m$ of width. The printed thickness of a electrode was about 300 to 500 nm, the surface roughness was about dozens nm under 50 nm.

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Reorganization of Chromatin Conformation from an Active to an Inactive State After Cessation of Transcription

  • Lee, Myeong-Sok
    • Journal of Microbiology
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    • v.34 no.1
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    • pp.54-60
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    • 1996
  • Taking advantage of the heat inducible HSP82 gene in yeast, chromatin structure after transcription cessation was investigated. Alteration of chromating conformation within the HSP82 gene transcription unit into an active state has been shown to correlate with its transcriptional induction. It was thus of interest to examine whether the active chromatin state within the HSP82 mRNA analysis, the gene ceased its transcription within a few hours of cultivation at a normal condition after heat induction. In this condition, an active chromatin conformation in the HSP82 gene body was changed into an inactie state which was revealed by DNase I resistance and by typical nucleosomal cutting periodicity in the corresponding chromatin. These results thus ruled out the possibility of a long-term maintenance of the DNase I sensitive chromatin after transcription cessation. DNA replication may be a critical event for the chromatin reprogramming.

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