• Title/Summary/Keyword: ANOVA(Analysis of Variance)

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Accelerated Resting-State Functional Magnetic Resonance Imaging Using Multiband Echo-Planar Imaging with Controlled Aliasing

  • Seo, Hyung Suk;Jang, Kyung Eun;Wang, Dingxin;Kim, In Seong;Chang, Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.4
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    • pp.223-232
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    • 2017
  • Purpose: To report the use of multiband accelerated echo-planar imaging (EPI) for resting-state functional MRI (rs-fMRI) to achieve rapid high temporal resolution at 3T compared to conventional EPI. Materials and Methods: rs-fMRI data were acquired from 20 healthy right-handed volunteers by using three methods: conventional single-band gradient-echo EPI acquisition (Data 1), multiband gradient-echo EPI acquisition with 240 volumes (Data 2) and 480 volumes (Data 3). Temporal signal-to-noise ratio (tSNR) maps were obtained by dividing the mean of the time course of each voxel by its temporal standard deviation. The resting-state sensorimotor network (SMN) and default mode network (DMN) were estimated using independent component analysis (ICA) and a seed-based method. One-way analysis of variance (ANOVA) was performed between the tSNR map, SMN, and DMN from the three data sets for between-group analysis. P < 0.05 with a family-wise error (FWE) correction for multiple comparisons was considered statistically significant. Results: One-way ANOVA and post-hoc two-sample t-tests showed that the tSNR was higher in Data 1 than Data 2 and 3 in white matter structures such as the striatum and medial and superior longitudinal fasciculus. One-way ANOVA revealed no differences in SMN or DMN across the three data sets. Conclusion: Within the adapted metrics estimated under specific imaging conditions employed in this study, multiband accelerated EPI, which substantially reduced scan times, provides the same quality image of functional connectivity as rs-fMRI by using conventional EPI at 3T. Under employed imaging conditions, this technique shows strong potential for clinical acceptance and translation of rs-fMRI protocols with potential advantages in spatial and/or temporal resolution. However, further study is warranted to evaluate whether the current findings can be generalized in diverse settings.

Comparison of Post Traumatic Stress Disorder according to Organizational Characteristics among Police Officers (경찰관의 조직적 특성에 따른 외상후 스트레스 장애 비교 분석)

  • Sin, Seong-Won
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.211-216
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    • 2012
  • In this study, the relationship between the organizational characteristics of police officers and the level of post-traumatic stress disorder in the comparative analysis was to check for post-traumatic stress disorder, according to the organizational characteristics affect. To accomplish this, a way ANOVA analysis of variance(One-way ANOVA) was conducted. The department in post-traumatic stress disorder level, a significant difference was found. It was more likely to be exposed to a traumatic experience if who is working in the front-line department. Post-traumatic stress disorder according to the work unit, a significant difference was found. The level of Post-traumatic stress disorder in outside job unit officers was higher than that of desk job unit offcers. Post-traumatic stress disorder according to the rank and duration of employment and the administrative district level, a significant difference was not found.

Geostatistical Interpretation of Cs-137 and K-40 Result of the Lithosphere in the Vicinity of Youngkwang Nuclear Power Plant (지구통계학적 방법에 의한 영광원전주변 토층내 Cs-137 및 K-40 측정 결과의 해석)

  • 김경웅;이재석;문승현;박철승;고일원;고은정;조병옥;정철영;전수열
    • Economic and Environmental Geology
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    • v.35 no.6
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    • pp.545-552
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    • 2002
  • In order to investigate the influence of nuclear power plant operation on its nearby environment, soil, stream and marine sediment samples were collected in the vicinity of the Youngkwang Nuclear Power Plant in Korea, and analyzed for artificial and natural radionuclide radioactivity. From the analytical result, Cs-137 was detected in most soil samples. but it may have been derived fiom past nuclear weapon tests because Cs-134 having short half-live was not detected. The radioactivities of Cs-137 in the sediment samples were also detected which are within the normal range in the sediments based upon the published literature between 1997 and 1999. For the quality control of radioactivity analysis of environmental samples, sets of marine sediments in the Gamami area were analyzed using two HPGe Gamma-ray Spectroscopes (30% and 45%) according to the geostatistical sampling strategy, and Cs-137 and K-40 results were interpreted by analysis of variance (ANOVA). In the two-way ANOVA, variances derived from the geochemical variation were significant, but errors from sampling and analytical procedures are negligible. In conclusion. all the radioanalytical procedures of this study including sampling are validated to be acceptable.

Comparative Analysis on the Levels of Stress by the Police Department Size (경찰관서 규모에 따른 스트레스 수준 비교 분석)

  • Sin, Seong-Won
    • The Journal of the Korea Contents Association
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    • v.13 no.12
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    • pp.463-469
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    • 2013
  • In this study, I examine whether differences in the levels of stress exist with regard to the police department size. To accomplish this, a way ANOVA analysis of variance(One-way ANOVA) was conducted. As a result, a significant difference was found in Job stress and traumatic stress according to the department size and grade. Specifically, first, in the job stress level on the department size, the smaller department size was, the higher job stress level was and the bigger department size was, the lower job stress level was. Second, in the traumatic stress level on the department size, the smaller department size was, the higher traumatic stress level was and the bigger department size was, the lower traumatic stress level was. Third, in the job stress level on the department grade, the lower department grade was, the lower job stress level was and the higher department grade was, the higher job stress level was. Fourth, in the traumatic stress level on the department grade, the lower department grade was, the lower traumatic stress level was and the higher department grade was, the higher traumatic stress level was.

The effects of repetitive firing processes on the optical, thermal, and phase formation changes of zirconia

  • Ozdogan, Alper;Ozdemir, Hatice
    • The Journal of Advanced Prosthodontics
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    • v.12 no.1
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    • pp.9-14
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    • 2020
  • PURPOSE. The aim of this study was to investigate the effect of different numbers of heat treatments applied to superstructure porcelain on optical, thermal, and phase formation properties of zirconia. MATERIALS AND METHODS. Forty zirconia specimens were prepared in the form of rectangular prism. Specimens were divided into four groups (n = 10) according to the number of firing at heating values of porcelain. Color differences and translucency parameter were measured, and X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) were performed. Data were analyzed with analysis of variance (ANOVA). RESULTS. There were no statistically significant differences in ∆E, TP, L, a, and b value changes of the zirconia specimens as a result of repetitive firing processes (P>.05). CONCLUSION. Although additional firing processes up to 4 increase peak density in thermal analysis, additional firing processes up to 4 times can be applied safely as they do not result in a change in color and phase character of zircon frameworks.

An Analysis of the Factors Determining Salary Level of Hospital (간호사의 임금수준 결정요인에 관한 연구)

  • Park, Hee-Ok
    • Journal of Korean Academy of Nursing Administration
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    • v.14 no.4
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    • pp.467-476
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    • 2008
  • Purpose: The purpose of this study was to examine the factors determining salary level of hospital. Methods: This study performed secondary analysis on the existing data. Data were collected from May 1, 2005 to September 30, 2005. Analysis of the results was carried out using SPSS win 12.0 program for t-test, ANOVA and multiple regression. Results: For the determinant factors on the level of nurse's salary, the R2 for this whole regression model was .72, indicating that approximately 72% of the variance in salary level of the nurses was accounted for by the linear combination of these three independent variables, the size of hospitals, the characteristics of a fund, and nursing delivery system. Conclusion: Salary is a major part of human resource management and is compensation for the labor of nurses and is a motive to nurses. Each hospital's salary needs to be more affordable to nurses.

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The Variation of Winter Buds among 10 Selected Populations of Kalopanax septemlobus Koidz. in Korea

  • Kim, Sea-Hyun;Ahn, Young-sang;Jung, Hyun-Kwon;Jang, Yong-Seok;Park, Hyung-Soon
    • Plant Resources
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    • v.5 no.3
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    • pp.214-223
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    • 2002
  • The objective of this study was to understand the conservation of gene resources and provide information for mass selection' of winter bud characters among the selected populations of Kalopanax septemlobus Koidz using analysis of variance(ANOVA) tests. The obtained results are shown below; 1. Ten populations of K. septemlobus were selected for the study of the variation of winter bud characters in Korea. The results of the analysis of variance(ANOVA) tests shows that there were statistically significant differences in all of the winter bud characters among those populations. 2. Correlation analysis shows that width between Height and DBH(Diameter at breast height) characters have negative relationship with all of the characters, as ABL(Apical branch length), ABW(Apical branch width), AWBL(Apical branch winter bud length), AWBW(Apical branch winter bud width), ABT(Apical branch No. of thorns), ABLB(Apical branch No. of lateral bud) and LBL(Lateral branch length), LBW(Lateral branch width), LBT(Lateral branch No. of thorns), LBLB(Lateral branch No. of lateral bud). 3. The result of principal component analysis(PCA) for winter buds showed that the first principal components(PC' s) to the fourth principal component explains about 78% of the total variation. The first principal component(PC) was correlated with AWBW, LWBW, and LBL and the ratio of ABL/ABW and LBL/LBW out of 16 winter bud characters. The second principal component correlated with ABL, ABW, ABLB, LWBL(Lateral branch winter bud length), and LBW and the ratio of AWBL/AWBW. The third principal component correlated with ABL, ABW, LWBL, LBL, and the ratio of LBL/LBW. The fourth principal component correlated with LBL and the ratio of LWBL/LWBW(Lateral branch winter bud width), LBL/LBW. Therefore, these characters were important to analysis of the variation for winter bud characters among selected populations of K. septemlobus in Korea. 4. Cluster analysis using the average linkage method based on 10 selected populations for the 16 winter bud characters of K. septemlobus in Korea showed a clustering into two groups by level of distance 1.1(Fig. 3). As can be seen in Fig. 3, Group I consisted of three areas(Mt. Sori, Mt. Balwang and Mt. Worak) and Group Ⅱ contisted of seven areas(Suwon, Mt. Chuwang, Mt. Kyeryong, Mt. Kaji, Mt. Jiri, Muan, and Mt. Halla). The result of cluster analysis for winter bud characters corresponded well with principal component analysis, as is shown in Fig. 2.

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A Study on the Relationship Between the Urban Homemaker's View of Homemanagement and the Domestic Courtesy and Ritual. (도시주부의 가정경영관과 가정의례와의 상관연구)

  • 이길표
    • Journal of the Korean Home Economics Association
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    • v.27 no.1
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    • pp.141-164
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    • 1989
  • The Purpose of this study is to investigate the relationship between the urban home-maker's view of homemanagement and the domestic courtesy and ritual (wedding ceremany, ancestral service, funeral rites). The data for this study was obtained from the 661 homemakers who live in Seoul, Busan, Inchon etc. The data were analyzed by the method described below with SPSS Computer programs. Such methods as frequence, percentile, analysis of variance (t-test, one-way ANOVA), Pearson's correlation and Factor analysis, Multiple regression were used. The major results the study can be summaried as follows; 1) As the result of factor analysis about view of homemanagement, 10 factors (which Eigen Value was above 1.0) out of 28 guestions were extracted. 2) In general, it can be said that the urban Homemaker's View of homemanagement varies by age, level of education, religion. 3) The domestic courtesy and ritual (wedding ceremony, ancestral servic, funeral rites) varies by age, level of education, religion. 4) There is a positive relation in analyzing the correlation between the urban homemaker's view of homemanagement and domestic courtesy and ritual (wedding ceremony, ancestral service, funeral rites)(p<.001).

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Structural Design for 2kW Class Wind Turbine Blade by using Design of Experiment (실험계획법을 이용한 2kW급 풍력발전용 블레이드에 대한 구조설계)

  • Lee, Seung-Pyo;Kang, Ki-Weon;Chang, Se-Myong;Lee, Jang-Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.28-33
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    • 2011
  • In this paper, structural design for 2kW class composite blade is performed by using design of experiment(DOE). A full factorial design is applied to meet the design specifications at the manufacturing process. The analysis of variance(ANOVA) is made in order to determine the significance of effects in an analysis. Structural analysis by using of commercial software ABAQUS is performed to compute the displacement and safety factor of filament wound composite blade. The results show that the proposed method is suitable to analyze the factors at the design of wind turbine blade.

How Derivational Prefix Instruction Impacts Incidental Vocabulary Acquisition and Reading Comprehension

  • Choi, Sung-Mook
    • English Language & Literature Teaching
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    • v.13 no.3
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    • pp.1-22
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    • 2007
  • The study examined the effects of explicit derivational morphology instruction (henceforth DMI) on the incidental vocabulary acquisition and reading comprehension of 132 Korean 1st-year high school students who responded to a battery of tests (two vocabulary tests and a reading comprehension test). Multiple statistical tools were used to analyze the data: Analysis of Covariance (ANCOVA), Analysis of Variance (ANOVA), Simple Regression Analysis, Tests of Simple Main Effects, and effect size computation using Cohen's d. The results indicated that (a) DMI enhanced students' ability to infer word meanings in context, (b) DMI promoted high proficiency students' reading comprehension, whereas it impeded intermediate proficiency students' reading comprehension, (c) vocabulary knowledge has a strong positive predictive value for reading comprehension, and (d) the gaps of vocabulary knowledge across proficiency levels were still substantial, despite the observation that DMI promoted students' vocabulary acquisition. These results have a bearing on English as Foreign Language (EFL) reading pedagogy.

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