• Title/Summary/Keyword: Confidence Evaluation

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Uncertainty Analysis of Dynamic Thermal Rating of Overhead Transmission Line

  • Zhou, Xing;Wang, Yanling;Zhou, Xiaofeng;Tao, Weihua;Niu, Zhiqiang;Qu, Ailing
    • Journal of Information Processing Systems
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    • v.15 no.2
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    • pp.331-343
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    • 2019
  • Dynamic thermal rating of the overhead transmission lines is affected by many uncertain factors. The ambient temperature, wind speed and wind direction are the main sources of uncertainty. Measurement uncertainty is an important parameter to evaluate the reliability of measurement results. This paper presents the uncertainty analysis based on Monte Carlo. On the basis of establishing the mathematical model and setting the probability density function of the input parameter value, the probability density function of the output value is determined by probability distribution random sampling. Through the calculation and analysis of the transient thermal balance equation and the steady- state thermal balance equation, the steady-state current carrying capacity, the transient current carrying capacity, the standard uncertainty and the probability distribution of the minimum and maximum values of the conductor under 95% confidence interval are obtained. The simulation results indicate that Monte Carlo method can decrease the computational complexity, speed up the calculation, and increase the validity and reliability of the uncertainty evaluation.

Influence of Social Presence on Consumer Purchase Decision at a Retail Store -Shopping Companions, Other Consumers, and Sales Associates- (리테일 매장에서 소비자 구매결정에 미치는 사회적 존재의 영향 -쇼핑동반자, 다른 고객, 판매원-)

  • Park, Kyungae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.42 no.6
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    • pp.962-976
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    • 2018
  • This study examined: 1) the influence of 3 social presence types including shopping companions, other consumers, and sales associates on the consumer's purchase decision at a retail store; 2) the difference in the influence by shopping situation involving shopping together or shopping alone; and 3) the differences by consumer susceptibility to social influence and self-confidence. The study conducted three experiments with the retail shopping scenario manipulating consumer's positive self-evaluation, but lack of confidence after trying on a clothing product. Experiment 1 and Experiment 2 examined the positive influence of social presence while Experiment 3 examined the negative influence. The results showed that the positive comment of a shopping companion had the highest influence on the purchase decision. Such impact was more observable under the low susceptibility to normative influence. The negative comments of sales associate and shopping companion lowered the purchase decision. There was no difference by shopping situation. The results imply that influences of social presence on the consumer's purchase decision are different by positive or negative comments and such influences are not different by shopping situation.

Convergence Effect of Simulation Training on Bleeding Amount Estimation in Trauma (시뮬레이션 교육이 외상성 출혈의 출혈량 추정에 미치는 융합적 영향)

  • Yang, Hyun-Mo;Kim, Gyoung-Yong
    • Journal of the Korea Convergence Society
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    • v.12 no.4
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    • pp.69-76
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    • 2021
  • The purpose of the study is to examine the visual evaluation of bleeding amount in hemorrhagic shock in paramedic students. Through manikin simulation training, paramedic students were able to have confidence with estimation of bleeding amount in the prehospital settings. Three rescue training manikins were placed in supine position and artificial blood was poured between the abdomen and pelvis. The bleeding evaluations of 700 mL, 1200 mL, and 1700 mL were performed before and after simulation training. Paramedic students underestimated the amount of bleeding in the trauma situation, and it was found that it was difficult for the students to evaluate the accurate amount of bleeding with a single simulation.

Development and evaluation of a neonatal intensive care unit medication safety simulation for nursing students in South Korea: a quasi-experimental study

  • Son, Mi Seon;Yim, Minyoung;Ji, Eun Sun
    • Child Health Nursing Research
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    • v.28 no.4
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    • pp.259-268
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    • 2022
  • Purpose: Nursing students are susceptible to medication safety incidents in the neonatal intensive care unit (NICU) related to a lack of communication experience. The purpose of the present study was to investigate the impact of a NICU medication safety simulation (NMSS) focusing on communication clarity, patient hand-off confidence, and patient safety competency in senior-year nursing students. Methods: The study utilized a nonequivalent control group pretest-posttest design. In total, 60 nursing students were assigned to two groups. The experimental group participated in the NMSS, which included three medication error scenarios. Pairs of students completed the scenarios together in 10 to 20 minutes. Data were analyzed using the chi-squared test, independent t test, and ANCOVA. Results: The experimental group showed significant improvements in communication clarity (p=.015), and patient safety competency (p<.001) compared to the control group. Using the pretest values as covariates, patient hand-off confidence scores significantly increased (p=.027). Conclusion: Implementing the NMSS focusing on communication in the pediatric nursing curriculum helped students to communicate clearly and concisely about medication errors, and its use is recommended to promote patient safety competency in the NICU.

The Patient Specific QA of IMRT and VMAT Through the AAPM Task Group Report 119 (AAPM TG-119 보고서를 통한 세기조절방사선치료(IMRT)와 부피적세기조절회전치료(VMAT)의 치료 전 환자별 정도관리)

  • Kang, Dong-Jin;Jung, Jae-Yong;Kim, Jong-Ha;Park, Seung;Lee, Keun-Sub;Sohn, Seung-Chang;Shin, Young-Joo;Kim, Yon-Lae
    • Journal of radiological science and technology
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    • v.35 no.3
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    • pp.255-263
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    • 2012
  • The aim of this study was to evaluate the patient specific quality assurance (QA) results of intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) through the AAPM Task Group Report 119. Using the treatment planning system, both IMRT and VMAT treatment plans were established. The absolute dose and relative dose for the target and OAR were measured by using an ion chamber and the bi-planar diode array, respectively. The plan evaluation was used by the Dose volume histogram (DVH) and the dose verification was implemented by compare the measured value with the calculated value. For the evaluation of plan, in case of prostate, both IMRT and VMAT were closed the goal of target and OARs. In case of H&N and Multi-target, IMRT was not reached the goal of target, but VMAT was reached the goal of target and OARs. In case of C-shape(easy), both were reached the goal of target and OARs. In case of C-shape(hard), both were reached the goal of target but not reached the goal of OARs. For the evaluation of absolute dose, in case of IMRT, the mean of relative error (%) between measured and calculated value was $1.24{\pm}2.06%$ and $1.4{\pm}2.9%$ for target and OAR, respectively. The confidence limits were 3.65% and 4.39% for target and OAR, respectively. In case of VMAT the mean of relative error was $2.06{\pm}0.64%$ and $2.21{\pm}0.74%$ for target and OAR, respectively. The confidence limits were 4.09% and 3.04% for target and OAR, respectively. For the evaluation of relative dose, in case of IMRT, the average percentage of passing gamma criteria (3mm/3%) were $98.3{\pm}1.5%$ and the confidence limits were 3.78%. In case of VMAT, the average percentage were $98.2{\pm}1.1%$ and the confidence limits were 3.95%. We performed IMRT and VMAT patient specific QA using TG-119 based procedure, all analyzed results were satisfied with acceptance criteria based on TG-119. So, the IMRT and VMAT of our institution was confirmed the accuracy.

The Effect of Self-reported Evaluation on Students' Mathematics Learning Styles (자기평가가 학습자의 수학 학습 성향에 미치는 영향)

  • Lee, Seon Jae;Ko, Ho Kyoung
    • Communications of Mathematical Education
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    • v.31 no.4
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    • pp.457-485
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    • 2017
  • The Self-reported Evaluation tool developed in this study allows the learners to check and evaluate their own learning by determining the details that are self-assessed. Also this tool allows learners to receive feedback on their self - evaluation results. In this study pre - post test was performed to investigate the effect of self - assessment on the learners' tendency of studying math. The result showed that Self-reported evaluation improved self - confidence, self - strategy on learning mathematics, and meta-cognitive ability. Also by conducting a qualitative analysis of the Self-reported evaluation, students practiced the cognitive activities such as summarizing the contents they have learned that day. They also tried to understand and improve the learning habit, attitude, and learning state. Teachers were also able to communicate with students by providing individual questions and feedback through student's individual Self-reported Evaluation.

A Framework for Quality Evaluation of Geospatial Data (Geospatial Data의 품질평가를 위한 Framework)

  • Cho, Gi-Sung
    • Journal of Korean Society for Geospatial Information Science
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    • v.4 no.2 s.8
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    • pp.123-136
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    • 1996
  • Lately, the demand for data standardization become increased to obtain various data jointly along with development of information technology and diversity of society. Thus the research on tile definition and evaluation of data quality indicating accuracy and confidence of geospatial data, is required for this standardization. In this study, by virtue of comparison of definitions and evaluation methods of data quality element being selected from representative countries, the following results were obtained: (1) Application of ISO/TC211's Draft having accepted evaluation standard to KSDTS(Korea Spatial Data Transfer Standard) is desirable for definitions of data quality elements. (2) This study presented the quality evaluation of much more resonable geospatial data accompaning with quality element. Furthermore, this study suggests that this evaluation be applicable to KSDTS and be contained in the digital map product specification of National Geography Institute with more clearness of a report form of data quality evaluation result. (3) Studies on various sampling methods, establishment of AQL(Acceptable Quality Level) suitable for our country, and computer programming which can rapidly and automatically evaluate mass much of data are required.

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An Analysis of the Properties of Affective Achievement in Science Based on TIMSS and Science Teachers' Perception (TIMSS 결과에 기초한 과학의 정의적 성취 특성 및 과학 교사의 인식 분석)

  • Kim, Miyoung;Cho, Jimin
    • Journal of The Korean Association For Science Education
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    • v.33 no.1
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    • pp.46-62
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    • 2013
  • In this study, nations with high academic achievement but disparate affective achievement in science according to the results of the TIMSS 2007 were selected and students' responses in the main survey for affective properties from those nations were analyzed. In addition, Korean science teachers' perception of affective achievement and the properties of teaching and learning science was explored by an online survey. According to the results of the analysis of students' responses in the main survey, the percentage of those with high levels of confidence in, pleasure in, and value perception of science was large for Hong Kong, Singapore, and England but small for Korea, Taiwan, and Japan. When the properties of teaching and learning in actual science classes were observed in Korea, actual classes focused little on experimentation, research activities, and the context of everyday life. According to the results of surveys conducted on science teachers, students' low confidence in science was due to difficult and uninteresting curricula and the absolute lack of time to study science and their low interest in the subject was due to difficult curricula and the view that science was unrelated to their future academic or professional careers. In addition, according to the teachers, students' low value perception of science curricula was due to the fact that there was no need to excel in science for academic or professional careers and the idea that the subject was of no help to daily life.

Uncertainty-based Decision on Mitigation of Nitrous Oxide Emissions in Upland Soil (불확도 기반 밭토양 아산화질소 배출 저감 여부 판정)

  • Ju, Okjung;Kang, Namgoo;Lim, Gapjune
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.4
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    • pp.307-316
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    • 2019
  • In the agricultural sector, greenhouse gas emissions vary depending on the interaction of all ecosystem changes such as soil environment, weather environment, crop growth, and anthropogenic farming activities. Agricultural sector greenhouse gas emissions resulting from many of these interactions are highly variable. Uncertainty-based evaluation that defines the interval with confidence level of greenhouse gas emission and absorption is necessary to take account of the variance characteristics of individual emissions, but research on uncertainty evaluation method is insufficient. This study aims to decide on the effect of reducing N2O emissions from upland soils using an uncertainty-based approach. An uncertainty-based approach confirmed whether there was a difference between confidence intervals in the 5 different fertilizer treatment groups to reduce greenhouse gas emissions. Unlike the statistically significant test with three repetition averages, the uncertainty-based approach method estimated in this study is able to estimate the confidence interval considering the distribution characteristics of the emissions, such as the dispersion characteristics of individual emissions. Therefore, it is considered that the reliability of emissions can be improved by statistically testing the variance characteristics of emissions such as the uncertainty-based approach. It is hoped that the direction of the uncertainty-based approach for the effect of reducing greenhouse gas emissions in agriculture will be helpful in the future development of agricultural greenhouse gas emission reduction technology, adaptation to climate change, and further development of sustainable eco-social system.

Statistical Approach for Determination of Compliance with Clearance Criteria Based upon Types of Radionuclide Distributions in a Very Low-Level Radioactive Waste (극저준위 방사성폐기물의 방사성핵종 분포유형에 기초하여 자체처분기준 만족여부를 판단하기 위한 통계학적 접근방법)

  • Cheong, Jae-Hak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.2
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    • pp.123-133
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    • 2010
  • A statistical evaluation methodology was developed to determine the compliance of candidate waste stream with clearance criteria based upon distribution of radionuclide in a waste stream at a certain confidence level. For the cases where any information on the radionuclide distribution is not available, the relation between arithmetic mean of radioactivity concentration and its acceptable maximum standard deviation was demonstrated by applying widely-known Markov Inequality and One-side Chebyshev Inequality. The relations between arithmetic mean and its acceptable maximum standard deviation were newly derived for normally or lognormally distributed radionuclide in a waste stream, using probability density function, cumulative density function, and other statistical relations. The evaluation methodology was tested for a representative case at 95% of confidence level and 100 Bq/g of clearance level of radioactivity concentration, and then the acceptable range of standard deviation at a given arithmetic mean was quantitatively shown and compared, by varying the type of radionuclide distribution. Furthermore, it was statistically demonstrated that the allowable range of clearance can be expanded, even at the same confidence level, if information on the radionuclide distribution is available.