• Title/Summary/Keyword: critical difference

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Distorted Bounding Surface of Clay with Consideration of the Effect of Temperature on Shearing Response (전단시 온도 영향을 고려한 점성토의 왜곡 경계면 모델 개발)

  • Woo, Sang Inn;Yune, Chan-Young
    • Journal of the Korean Geotechnical Society
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    • v.36 no.12
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    • pp.117-124
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    • 2020
  • The present research focuses on a methodology to describe shearing response of clay with respect to temperature. An increase of temperature shifts the normal consolidation line to move down in the plane of void ratio and mean effective stress. The critical state line, however, does not move as much as the normal consolidation line in accordance with temperature increase. As temperature increase, therefore, the difference between the critical state mean effective stress and the pre-consolidation pressure reduces. To reflect this easily, the present study applies a bounding surface consisting of two parts divided by the critical state mean effective stress. This study calibrated a bounding surface for the soft Bangkok clay and performed elemental simulation for undrained triaxial compression tests. The elemental simulation showed that the model can describe the mechanical response upon temperature of clay without complex hardening and evolution rules compared to the experimental data.

Experimental study and analysis of design parameters for analysis of fluidelastic instability for steam generator tubing

  • Xiong Guangming;Zhu Yong;Long Teng;Tan Wei
    • Nuclear Engineering and Technology
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    • v.55 no.1
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    • pp.109-118
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    • 2023
  • In this paper, the evaluation method of fluidelastic instability (FEI) of newly designed steam generator tubing in pressurized water reactor (PWR) nuclear power plants is discussed. To obtain the parameters for prediction of the critical velocity of FEI for steam generator tubes, experimental research is carried out, and the design parameters are determined. Using CFD numerical simulation, the tube array scale of the model experiment is determined, and the experimental device is designed. In this paper, 7 groups of experiments with void fractions of 0% (water), 10%, 20%, 50%, 75%, 85% and 95% were carried out. The critical damping ration, fundamental frequency and critical velocity of FEI of tubes in flowing water were measured. Through calculation, the total mass and instability constant of the immersed tube are obtained. The critical damping ration measured in the experiment mainly included two-phase damping and viscous damping, which changed with the change in void fraction from 1.56% to 4.34%. This value can be used in the steam generator design described in this paper and is conservative. By introducing the multiplier of frequency and square root of total mass per unit length, it is found that the difference between the experimental results and the calculated results is less than 1%, which proves the rationality and feasibility of the calculation method of frequency and total mass per unit length in engineering design. Through calculation, the instability constant is greater than 4 when the void fraction is less than 75%, less than 4 when the void fraction exceeds 75% and only 3.04 when the void fraction is 95%.

Effect of Virtual Reality Women Health Nursing Practicum on Meta-cognition and Critical Thinking: Mixed Method Study (가상현실 기반 여성건강간호학 실습교육이 메타인지와 비판적 사고에 미치는 효과: 혼합연구 방법)

  • Hyun Kyoung Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.481-486
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    • 2023
  • This study applied virtual reality to women health nursing practicum for nursing students and analyzed the educational effect on meta-cognition and critical thinking. The study design was a convergent mixed method using single-group pre-post test design and individual in-depth interviews. After applying the virtual reality program, the post-score (104.16±12.98) was statistically significantly higher than the pre-score (98.59±18.09) (t=1.85, p=.030). There was no statistically significant difference in critical thinking after the program, with the post-score of 101.66±7.18 and the pre-score of 99.18±15.13 (t=1.00, p=.108). Therefore, women health nursing practice education using virtual reality can help improve the meta-cognition of nursing students.

Relationship between Problem Solving Ability, Critical Thinking Disposition, Creativity, Self Efficacy and Nursing Process Competence of Nursing Students (간호대학생의 문제해결능력, 비판적 사고 성향, 창의성, 자기효능감과 간호과정 수행능력과의 관계)

  • Yang, Sun-Hee;Sim, In-Ok
    • The Journal of the Korea Contents Association
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    • v.16 no.5
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    • pp.612-622
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    • 2016
  • The purpose of this study was to identify the relationship between problem solving ability, critical thinking disposition, creativity and nursing process competence of nursing students. The participants in the study were 246 nursing students enrolled in 2nd year of a BSN program in S city, Korea. Data were collected from June 10 to June 20, 2015 using a structured questionnaire. Relationship between general characteristics and solving ability, critical thinking disposition, creativity and nursing process competence was analyzed by t-test, ANOVA and Kruskal-wallis. Correlation among problem solving ability, critical thinking disposition, creativity and nursing process competence was analyzed by pearson correlation coefficient. There was a statistically significant difference in problem solving with the reason for application, major satisfaction. There was a significant positive correlation between problem solving ability, critical thinking disposition, creativity and self efficacy. Nursing process competence was't a significant between problem solving ability, critical thinking disposition, creativity and self efficacy. These findings show that there is a need to develop strategies to improve self efficacy and nursing process competence for student nurses.

Critical Thinking Disposition, Problem Solving Process, and Simulation- Based Assessment of Clinical Competence of Nursing Students in Pediatric Nursing (간호대학생의 비판적 사고성향, 문제해결과정 정도 및 아동간호 시뮬레이션 기반 임상수행능력)

  • Kim, Sunghee;Nam, Hyuna;Kim, Miok
    • Child Health Nursing Research
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    • v.20 no.4
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    • pp.294-303
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    • 2014
  • Purpose: The purpose of this study was to identify the correlation of critical thinking disposition and problem solving process, and the simulation- based assessment of clinical competence based on a survey of college nursing students. Methods: In this descriptive correlation study, data for 214 nursing students were analyzed using t-test and Pearson correlation coefficients. Results: Critical thinking disposition, problem solving process, and simulation-based assessment of clinical competence averaged $3.76{\pm}0.46$ (out of 5), $3.67{\pm}0.47$ (5), and $1.51{\pm}0.17$ (2), respectively. A significant difference in scores for simulation-based assessment of clinical competence was found between the high-scoring group and low-scoring group in critical thinking disposition. A significant positive correlation was found between critical thinking disposition and nursing assessment, a sub-domain of clinical competence. Conclusion: The results suggest that success in simulation-based learning requires critical thinking disposition in the nursing students, and their critical thinking disposition plays a positive role in nursing assessment, which evaluates the patient's status in a complex situation. Simulation-based learning programs help assess the students' levels in their clinical judgement and performance, and identify their strengths and weaknesses so that the instructor can evaluate and improve the current teaching method.

Diagnostic Value of Interleukin 21 and Carcinoembryonic Antigen Levels in Malignant Pleural Effusions

  • Bunjhoo, Hansvin;Wang, Zheng-Yun;Chen, Hui-Long;Cheng, Sheng;Xiong, Wei-Ning;Xu, Yong-Jian;Cao, Yong
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3495-3499
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    • 2012
  • The aim of this study was to evaluate the diagnostic value of interleukin 21(IL-21) and carcinoembryonic antigen (CEA) in tuberculous pleural effusions (TPEs) and malignant pleural effusions (MPEs). Pleural effusion samples from 103 patients were classified on the basis of diagnosis as TPE (n=51) and MPE (n=52). The concentration of IL-21 was determined by ELISA. Lactate dehydrogenase (LDH), adenosine dehydrogenase (ADA) and CEA levels were also determined in all patients. A significant difference was observed in the levels of ADA and CEA (P<0.01), but not in the levels of LDH (P>0.05) between TPE and MPE. The concentration of IL-21 in MPE was significantly higher compared to TPE (P<0.01). With a threshold value of 4.32 pg/ml, IL-21 had a sensitivity of 76.9% (40/52) and a specificity of 80.4% (41/51). Combined detection of IL-21 and CEA had a sensitivity of 69.2% (36/52) and a specificity of 92.2% (47/51). These two markers can contribute to the differential diagnosis of MPEs.

Association between Critical Thinking Disposition and Grade Point Average Score in Dental Hygiene Students (치위생(학)과 학생의 학업성적에 따른 비판적 사고 성향)

  • Hwang, Hye-Rim;Kim, Eung-Kwon;Cho, Young-Sik
    • Journal of dental hygiene science
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    • v.12 no.1
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    • pp.7-13
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    • 2012
  • Critical thinking is a essential competency for dental hygiene education and practice. The purpose of this study was to examine critical thinking disposition between groups classified by GPA score in two dental hygiene educational program. A total 252 dental hygiene students responded. The study extracted six dimensions(intellectual eagerness/curiosity, prudence, healthy skepticism, intellectual integrity, objectivity, self-confidence) derived from 27 items with the exception of systematicity using factor analysis. The mean score for critical thinking disposition was 3.47 on a 5 point scale. The result showed a statistically significant correlation critical thinking disposition and age. Multivariate analysis of covariance(MANCOVA) was used to compare six subscales between the three groups. MANCOVA results revealed that intellectual eagerness/curiosity for three groups were significantly different(Wilks's lamda=0.914, F(6, 24)=1.869), p=0.01, partial eta square=0.044). Multiple comparison for intellectual eagerness/curiosity by Scheffe's method showed differences between high score group and mid score group(p=0.027), high score group and low score group(p=0.002). In this study, academic achievement and critical thinking tends to show significant correlations is known. Critical thinking skills by examining the actual grade compares the difference in propensity scores according to a case study in intellectual curiosity, passion, and could tell the difference to appear.

Stability analysis of Au/YBCO film (Au/YBCO 박막의 안정성 해석)

  • 김진석;설승윤
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.245-248
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    • 2002
  • One dimensional conduction equation is solved by finite difference method, to analyse the stability of Au/YBCO film deposited on a sapphire substrate. Jolue heat is included in the case of current sharing state. The analysis shows the quench and recovery of superconductor depending on the amount of thermal disturbance release on the center surface of superconductor. The critical disturbance energies for different filling factor and operating current are calculated.

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