• Title/Summary/Keyword: T-test analysis

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Dynamic Analysis and Experimental Verification of Brake Judder considering Quality (품질을 고려한 브레이크 저더의 동역학 해석 및 시험 검증)

  • 김효식;임홍재
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.365-370
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    • 2003
  • The problem of brake judder is typically caused by quality defects in manufacturing. This quality problem, however, can't be controlled deterministically and requires analyses and designs considering uncertainties. This paper presents a method for dynamic analysis of a brake judder considering uncertainties. Firstly, quality defects, which come from the uncertainties, are determined by examination of symptoms of the brake judder quality problem. Effective quality defects are selected by investigation of process capability and comparison of sensitivity of each quality defects and noise levels of the effective quality defects are determined. Secondly, flexible multibody dynamic analysis and finite element analysis according to the proposed method are carried out. Finally, The analysis results are compared with the test results with noise levels of the effective quality defects.

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The Effects of Perception of gender in People with Developmental Disabilities on Life Satisfaction

  • JungHyun Kim
    • International Journal of Advanced Culture Technology
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    • v.12 no.3
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    • pp.271-277
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    • 2024
  • The purpose of this study was to empirically analyze the effect of gender perception on the life satisfaction of people with developmental disabilities. Based on the results, it was intended to suggest practical measures to improve the developmentally disabled's awareness of their gender and quality of life. To achieve the purpose of the study, a survey was conducted with a significant sample of people with developmental disabilities aged 30 or older in Ulsan City. It was done. Of the collected questionnaires, 58 copies were used as final analysis data, excluding unfaithful responses. The collected data were factor analysis, reliability analysis, frequency analysis, Pearson correlation analysis, t/F-test, and regression analysis using SPSS 20.0 It was implemented. Based on the analysis results, the development of gender education programs for people with developmental disabilities to provide knowledge and information about gender and developmental disabilities. It suggested establishing experts and counseling institutions dedicated to gender and implementing and promoting social education for the general public.

Comparison of longitudinal treatment effects with facemask and chincup therapy followed by fixed orthodontic treatment on Class III malocclusion (상악전방견인장치와 이모장치 및 고정식 교정장치 치료를 받은 III급 부정교합 환자의 치료효과에 대한 종단적 비교)

  • Lee, Nam-Ki;Baek, Seung-Hak
    • The korean journal of orthodontics
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    • v.39 no.6
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    • pp.362-371
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    • 2009
  • Objective: The purpose of this study was to compare the longitudinal treatment effects of facemask with rapid maxillary expansion (FM/RME) and chincup (CC) therapy followed by fixed orthodontic treatment (FOT) in Class III malocclusion (CIII) patients. Methods: The samples consisted of twenty-one CIII patients who had similar skeletal and dental characteristics before FM/RME or CC therapy and good retention results (Class I molar/canine relationship and positive overbite/overjet) after FOT (Group 1, FM/RME, n = 11; Group 2, CC, n = 10). Lateral cephalograms were taken before (T0) and after FM/RME or CC therapy (T1), and after FOT and retention (T2). Skeletal and dental variables were measured. Mann-Whitney U-test and Wilcoxon signed-rank test were used for statistical analysis. Results: During T0-T1, FM/RME therapy induced forward movement of point A, and labioversion of the upper incisors. Both groups showed posterior repositioning of the mandible. FM/RME resulted in increase of the vertical dimension; however, CC caused an increase in articular angle and decrease in gonial angle. During T1-T2, both groups exhibited forward growth of point A. Group 1 showed forward growth and counterclockwise rotation of the mandible and increase of IMPA; however, Group 2, showed increase of ANS-Me/N-Me and decrease of overbite. Conclusions: The key factor for successful FM/RME and CC therapy and good retention results might be a harmonized forward growth of the maxilla that could keep pace with the growth and rotation of the mandible.

The effect of zirconia surface architecturing technique on the zirconia/veneer interfacial bond strength

  • Her, Soo-Bok;Kim, Kyoung Hun;Park, Sang Eun;Park, Eun-Jin
    • The Journal of Advanced Prosthodontics
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    • v.10 no.4
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    • pp.259-264
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    • 2018
  • PURPOSE. The purpose of this study was to evaluate the effect of the zirconia surface architecturing technique (ZSAT) on the bond strength between veneering porcelain and zirconia ceramic. MATERIALS AND METHODS. 20 sintered zirconia ceramic specimens were used to determine the optimal surface treatment time, and were randomly divided into 4 groups based on treatment times of 0, 1, 2, and 3 hours. After etching with a special solution, the surface was observed under scanning electron microscope, and then the porcelain was veneered for scratch testing. Sixty 3 mol% yttria-stabilized tetragonal zirconia polycrystal ceramic blocks were used for tensile strength testing; 30 of these blocks were surface treated and the rest were not. Statistical analysis was performed using ANOVA, the Tukey post-hoc test, and independent t-test, and the level of significance was set at ${\alpha}=.05$. RESULTS. The surface treatment of the zirconia using ZSAT increased the surface roughness, and tensile strength test results showed that the ZSAT group significantly increased the bond strength between zirconia and veneering porcelain compared to the untreated group (36 MPa vs. 30 MPa). Optimal etching time was determined to be 2 hours based on the scratch test results. CONCLUSION. ZSAT increases the surface roughness of zirconia, and this might contribute to the increased interfacial bond strength between zirconia and veneering porcelain.

A Study on the Characteristics of Creativity Factors Found in Elementary and Middle School Creative Gifted Student Selection Test (초.중학생 창의성 영재 선발 검사에 나타난 창의성 요인별 특성 연구)

  • Son, Chung-Ki;Kim, Myeong-Cheol
    • Journal of Gifted/Talented Education
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    • v.17 no.2
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    • pp.307-337
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    • 2007
  • The purpose of this study is to verify the validity of a creativity measurement tool and to discover the creativity characteristics of creative gifted students by assessing the difference in the creativity characteristics of creative gifted students, who were selected from gifted students in elementary and middle schools through the Torrance Test of Creative Thinking(TTCT), according to school level and the type of the students (gifted student in mathematics, gifted student in science). To this research purpose, creative gifted students were selected by the Torrance Test of Creative Thinking(TTCT) on 594 students, who had applied for super gifted education, from 17 gifted students institutes under the jurisdiction of Jeollabukdo office of education, Then, t-tests and multiple regression analysis were performed to analyze the creativity factors between elementary students and middle school students and between mathematics-gifted students and science-gifted students. From the research, the following results were obtained. Although TTCT is effective in distinguishing gifted students with and without creativity, correlation coefficient values between creativity factors(the correlation coefficients between 'fluency' and 'originality' and between 'fluency' and 'elaboration' were .78 and .50 respectively) suggested the possibility of low uniqueness of creativity factors. In addition, compared with elementary students, middle school students showed significantly lower fluency (circles), elaboration(picture construction, picture completion), and the abstractness of titles(picture structure). In the meantime, science-gifted students displayed significantly higher originality(picture construction), and elaboration(picture construction, picture completion, circles) than mathematics-gifted students. Therefore, continuous study is required to enhance the validity of the test for the selection of creativity gifted students. Besides, efforts should be made to find ways to enhance the creativity of gifted students and to resolve the problem of decreasing creativity with student academic level increasing.

A Experimental Study on the Visual Effect of Details on Ensemble Suits (I) -for Elderly Women- (앙상블 수트의 의복형태구성요인의 시각효과에 대한 실험연구 (제1보) -노년층 여성을 중심으로-)

  • 조훈정;손영미
    • Journal of the Korean Society of Costume
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    • v.52 no.6
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    • pp.51-69
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    • 2002
  • The purpose of this study was to classify the body shapes. exclusive of size and corpulence factors of more than 60-year old elderly women by distinctions, and to investigate the visual effects of combination of ensemble suit details. For the body shape classification, the factor analysis and cluster analysis were performed : the mean value difference of numeral values for classified types were tested by ANOVA : and the follow-up test was conducted by the Duncan's multiple ranged test. The data analysis for visual effects evaluated by a multiple ranking test was analysed by mean. paired t-test, ANOVA and Duncan's multiple ranged test. The results are summarized as follows : 1. The followings are the types of body shape according to the shape factors of the front line of body for elderly women. The distinctions of the front li e of elderly women's body could be presumed; that was, Body typeⅠ was a comparatively well-balanced body type, Body type Ⅱ was close to an average body type. and Body type In was a severely corpulent body type. 2. The followings are the results on the physical visual effects inducing the constituents of clothing type. 1) The neckline·collar types of a jacket have a great influence on the visual effects of the upper body, and orderly. the tailored collar. soutien collar, and round neckline had positive influence on the visual effects in the upper body. 2) The pleat types of one-piece dress had positive influence on the visual effects in the lower body in the order of gored type, pleats type, and gathered type. Also. the balance in the lower body had more influence on the overall balance of the clothing compared to the constituents of clothing type such as neckline collar type or opening line. 3) It showed that whether there is the front opening line of a jacket influenced on the visual effects of all categories.

Development and Effectiveness of Practice Application Program of Intravenous Infusion Evidence-Based Nursing Practice Guideline - for Small and Medium Sized Hospitals (근거기반 정맥주입요법 간호실무지침 실무적용 프로그램 개발 및 평가 - 중소병원을 대상으로)

  • Hong, Inhwa;Eun, Young
    • Journal of Korean Academy of Nursing
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    • v.50 no.6
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    • pp.863-875
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    • 2020
  • Purpose: This study was conducted to develop and test the effects of a program for practice application of intravenous infusion evidence based nursing practice (EBP) guidelines in small and medium-sized hospitals. Methods: A mixed method research design was used, combining non-equivalent control group pre-post test design with qualitative study analysis. The subjects consisted of 55 nurses. The practice application program was developed based on the Advancing Research and Clinical practice through close Collaboration (ARCC) model. Data were collected for analysis in the following areas: nurses' EBP organizational culture and readiness, EBP beliefs, EBP implementation, importance about intravenous infusion, and performance about intravenous infusion, with data assessed using valid and reliable instruments. Patient outcomes were collected from the hospital's medical records. Data were analyzed using t-test, χ2-test, and Shapiro-Wilk test, with qualitative content analysis used for interview data. Results: Following the intervention, nurses' EBP organizational culture and readiness, EBP beliefs, EBP implementation, and performance of intravenous infusion and perceptions of its importance showed significant improvement in the experimental group. Phlebitis rates decreased in the experimental group compared to the control group. Conclusion: This program is effective to improve nurse's perception and practice of evidence based nursing. Therefore we recommend to use this program at same levels of hospitals.

Mediating Effects of Resilience on the Relation between Emotional Intelligence and Self-Efficacy on Career Decision-Making in Nursing Students (간호대학생의 감성지수가 진로결정자기효능감에 미치는 영향: 회복탄력성의 매개효과 중심으로)

  • Lim, Hyun-Suk;Ryu, Jeong-Lim
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.11
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    • pp.151-160
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    • 2020
  • The purpose of this study was to investigate the moderating mediation effect of resilience, on the relationship between emotional intelligence and self-efficacy in career decision-making of nursing students. The participants were 136 nursing college students in the Jeonbuk region. Data was collected in September 2020 via a structured questionnaire survey. The data was analyzed using the SPSS/23.0 program. The analysis used descriptive statistics, Pearson's correlation coefficient, independent t-test, one-way ANOVA, multiple regression analysis, and Sobel's tests. The results showed that emotional intelligence was a circle activity (F=3.13, p=.047), and motivation to nursing (F=4.16, p=.008). Resilience was a circle activity (F=5.50, p=.005), and nursing major satisfaction (t=2.19, p=.031). Career decision-making self-efficacy showed significant differences in grade (F=3.12, p=.048) and major satisfaction (t=2.36, p=.020). Emotional intelligence and resilience (r=.63, p<.001), emotional intelligence and career decision-making self-efficacy (r=.67, p<.001), resilience and career decision-making self-efficacy (r=.76, p<.001) showed significant static correlation. In emotional intelligence and career decision-making self-efficacy, resilience had a partial mediating effect (Z=6.48, p<.001), and explanatory power was 62.2%. Based on the results of this study, to improve the emotional intelligence and career decision-making self-efficacy of nursing students, it is necessary to develop a personalized and resilience-enhanced education program.

Estimation of Weaning Age Effects on Growth Performance in Berkshire Pigs

  • Do, C.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.2
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    • pp.151-162
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    • 2012
  • Analysis for back fat thickness (BFAT) and daily body weight gains from birth to the end of a performance test were conducted to find an optimal method for estimation of weaning age effects and to ascertain impacts of weaning age on the growth performance of purebred Berkshire pigs from a closed population in Korea. Individual body weights were measured at birth (B), at weaning (W: mean, 22.9 d), at the beginning of the performance test (P: mean, 72.7 d), and at the end of the performance test (T: mean, 152.4 d). Further, the average daily gains in body weight (ADG) of 3,713 pigs were analyzed for the following periods: B to W (DGBW), W to P (DGWP), P to T (DGPT), B to P (DGBP), B to T (DGBT), and W to T (DGWT). Weaning ages ranged from 17 to 34 d, and were treated as fixed (WF), random with (WC) and random without (WU) consideration of an empirical relationship between weaning ages in the models. WF and WC produced the lowest AIC (Akaike Information Criterion) and least fractions of error variance components in multi-traits analysis, respectively. The fractions of variances due to diverse weaning age and the weaning age correlations among ADGs of different stages (when no overlapping allowed) by WC ranged from 0.09 to 0.35 and from -0.03 to 0.44, respectively. The maximum weaning age effects and optimal back fat thicknesses were attained at weaning ages of 27 to 32 d. With the exception of DGBW, the effects of weaning age on the ADGs increased (ranging from 1.50 g/d to 7.14 g/d) with increased weaning age. In addition, BFAT was reduced by 0.106 mm per increased day in weaning age. In conclusion, WC produced reasonable weaning age correlations, and improved the fitness of the model. Weaning age was one of crucial factors (comparable with heritability) influencing growth performance in Berkshire pigs. Further, these studies suggest that increasing weaning age up to 32 d can be an effective management strategy to improve growth performance. However, additional investigations of the costs and losses related to extension of the suckling period and on the extended range of weaning age are necessary to determine the productivity and safety of this practice in a commercial herd and production system.

A Study on Effectiveness of Inclusive Education Program in Social Welfare Institutions for Handicapped Children (장애아동복지시설에서의 통합교육 프로그램 효과성에 관한 연구)

  • Han, Kyung-Sung;Kim, Tae-Baik
    • Korean Journal of Social Welfare
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    • v.59 no.1
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    • pp.55-85
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    • 2007
  • This study analyzed the effect of the inclusion program executed in a social welfare institution for handicapped children of community in order to support inclusive education of elementary school. The statistical analyses adapted in this study were the Frequency Analysis, T-test, One-Way ANOVA, Correlation Analysis, Two-Way ANOVA, and ANCOVA. As the results of the analyses, there was significant difference of the increase in the scores between pre-test attitude and attitude improvement of normal children (nonhandicapped children) by intervention of the inclusion program. Secondly three variables such as the sex, the experience of integrated class, and the school environment gave influence on attitude improvement of normal children, but two variables such as the school year and the religion didn't give influence on attitude improvement of normal children. However, as the results of the ANCOVA, it was appeared that both the school year variable and the religion variable didn't give influence on attitude improvement of normal children. Consequently, as the attitude improvement of normal children was irrelevant to the characteristic variables such as the school year and the religion, it is verified that the inclusion program gives still significant impact in the difference between pre-test attitude and attitude improvement of normal children. In conclusion, As the pure effectiveness of the inclusion program executed in social welfare institutions for handicapped children in order to support inclusive education of elementary school was confirmed, it was suggested in this study that the inclusion program in the field of social work practice based community can be an important tool of social integration through inclusive education between handicapped children and normal children.

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