• 제목/요약/키워드: Confidence Evaluation

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A Study on the Transport-related Impacts of Flexible Working Policy using Activity-Based Model (활동기반모형을 이용한 유연근무제의 교통부문 영향 연구)

  • CHO, Sung-Jin;BELLEMANS, Tom;JOH, Chang-Hyeon;CHOI, Keechoo
    • Journal of Korean Society of Transportation
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    • v.35 no.6
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    • pp.511-524
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    • 2017
  • This study aims to evaluate the availability of ABM (Active-Based Model), FEATHERS, as a policy evaluation tool. To achieve the goal, scenario analysis on flexible working policy was conducted to measure its impact on activity-travel behavior. As a consequence, there seems no significant change in worker's daily life, other than mitigating traffic congestion due to decreasing commuting travel in the rush hour. The result of VKT (vehicle kilometers traveled) shows an opposite pattern according to given household/individual constraints. The scenario analysis on telecommuting indicates a decreasing trend in both travel frequency and distance because of the diminished number of commuting trips. As the activity space of telecommuters is shifted to a residential area, there are more short-distance trips by using non-motorized transport, which leads to decrease in VKT (using a private vehicle). Thus, the sensitivity of VKT by population groups varies due to transport mode shift (between personal and another mode) and growing non-work trips (using a private mode). This study found few things. First, it is necessary to evaluate the details of policy impact by population groups since it can be varied depending on household/individual characteristics. Second, the case study shows a promising performance of ABM as policy measurement that provides reality in policy evaluation. Third, ABM allows us to do more accurate analysis (i.e. time-series analysis by population groups) of policy assessment than those of FSM (Four-Step Model). Lastly, a further effort in data collection, literature review, and expert survey should be made to enhance the accuracy and confidence of future research.

Feature-based Non-rigid Registration between Pre- and Post-Contrast Lung CT Images (조영 전후의 폐 CT 영상 정합을 위한 특징 기반의 비강체 정합 기법)

  • Lee, Hyun-Joon;Hong, Young-Taek;Shim, Hack-Joon;Kwon, Dong-Jin;Yun, Il-Dong;Lee, Sang-Uk;Kim, Nam-Kug;Seo, Joon-Beom
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.237-244
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    • 2011
  • In this paper, a feature-based registration technique is proposed for pre-contrast and post-contrast lung CT images. It utilizes three dimensional(3-D) features with their descriptors and estimates feature correspondences by nearest neighborhood matching in the feature space. We design a transformation model between the input image pairs using a free form deformation(FFD) which is based on B-splines. Registration is achieved by minimizing an energy function incorporating the smoothness of FFD and the correspondence information through a non-linear gradient conjugate method. To deal with outliers in feature matching, our energy model integrates a robust estimator which discards outliers effectively by iteratively reducing a radius of confidence in the minimization process. Performance evaluation was carried out in terms of accuracy and efficiency using seven pairs of lung CT images of clinical practice. For a quantitative assessment, a radiologist specialized in thorax manually placed landmarks on each CT image pair. In comparative evaluation to a conventional feature-based registration method, our algorithm showed improved performances in both accuracy and efficiency.

Basic Evaluation of Analytical Performance and Clinical Utility of Immunoradiometric TSH Assay (면역방사 계수측정법 (Immunoradiometric, Assay)에 의한 혈청 TSH 측정의 기본적 검토 및 임상적 의의)

  • Suh, Kyo-Il;Cho, Bo-Youn;Lee, Hong-Kyu;Koh, Chang-Soon;Min, Hun-Ki;Lee, Mun-Ho
    • The Korean Journal of Nuclear Medicine
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    • v.21 no.2
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    • pp.143-150
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    • 1987
  • To assess the analytic performance of immunoradiometric TSH assay (IRMA TSH), assay precision determined by intra and interassay variance, assay accuracy determined by dilution and recovery study, were evaluated by using two commercial kit $(Abott^{(R)}\;and\;Daichi^{(R)})$. Normal range of basal serum TSH and TRH stimulated TSH increment were also determined in 234 healthy subjects (male 110, female 124; age 20-70) and 30 voluteers (male 10, female 20; age 21-26). In addition, basal TSH levels of 70 patients with untreated hyperthyroidism, 50 untreated hypothyroidism, and 60 euthyroidism were measured to assess the clinical utility of IRMA TSH. The detection limit of IRMA TSH was 0.04 mU/l and 0.08 mU/l by Abott Kit and Daichi kit respectively. Using Abott kit, intra assay variance were 2.0, 3.1 and 1.4% in mean TSH concentration 2.4, 31.6 and 98.2 mU/l repectively and interassay variance were 2.0 and 3.2% in mean TSH concentration 2.3 and 31.3 mU/l. Mean recovery rate was 92.5% and dilution study showed nearly straight line. When Daichi kit was used, intrasssay variance were 5.6, 5.2 and 6.2% in mean TSH concentration of 2.4, 31.6 and 98.2 mU/l respectively and interassay variance were 7.1 and 7.4% in mean TSH of 2.3 and 31.3 mU/l. Mean recoveray rate was 89.9%. Normal range of basal TSH and TRH stimulated peak TSH were 0.38-4.02 mU/l and 2.85-30.8 mU/l repectively (95% confidence interval, Abott kit used). Sensitivity and specificity of basal TSH levels for diagnosing hypothyroidism as well as specificity for diagnosing hyperthyroidism were 100% by using both kit. Sensitivity of basal TSH level for diagnosing hyperthyroidism was 100% when TSH levels were measured by Abott kit while that was 80.9% when measured by Daichi kit. These results suggest that IRMA TSH was very precise and accurate method and might be used as a first line test in the evaluation of thyroid function.

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Validation and Uncertainty Evaluation of an Optimized Analytical Method Using HPLC Applied to Canthaxanthin, a Food Colorant (식품 색소 Canthaxanthin의 HPLC 최적 분석법 확인 및 타당성과 측정불확도 평가)

  • Suh, Hee-Jae;Kim, Kyung-Su;Hong, Mi-Na;Lee, Chan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.3
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    • pp.342-351
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    • 2016
  • This study was carried out to develop an optimized analytical method using high-performance liquid chromatography (HPLC) applied to canthaxanthin, which is not yet designated as a food colorant in Korea, as well as to perform validation and uncertainty evaluation of this method. Official methods of AOAC, UK, and Japan with HPLC-UV detection were evaluated for the analysis of canthaxanthin by comparison of linearity, resolution, selectivity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision, recovery, inter-laboratory tests, and uncertainty measurement. The calibration curves showed high linearity with an $R_2$ value of over 0.999 for canthaxanthin standard solutions in all three official methods. The official method of Japan exhibited the best results in terms of resolution and selectivity, including the lowest LOD and LOQ. The average coefficients of variation were calculated as less than five of three institutes with a precision value less than 1, accuracy near 100%, and recovery ratio between $100{\pm}10%$. The expanded uncertainty for canthaxanthin was estimated to be $39.5{\pm}5.29mg/kg$ (95% confidence level, k=2), and the uncertainty of measurement was 13.4%. In this study, official methods of canthaxanthin were compared and the validities verified. The results will be further applied to establish an authorized analytical method for canthaxanthin in Korea.

A Study of the Effectiveness of Basic CPR (Cardiopulmonary Resuscitation) Education of Primary School Children (일부 초등학생의 기본심폐소생술 교육효과에 대한 연구)

  • Kang, Hea-Eun;Kim, Hyeon-Suk;Kim, Yun-Shin
    • Journal of the Korean Society of School Health
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    • v.24 no.1
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    • pp.118-128
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    • 2011
  • Purpose: This research is based on experiments practiced with 6th grade students in primary school as subjects. They were trained in basic cardiopulmonary resuscitation theory and received actual training in CPR. Methods: The subjects were randomly sorted into two classes of the 6th grade students. The experimental group was composed of 35 students. The control group was composed of 32. The experimental group received basic CPR theoretical and practical education once and received a practical evaluation three times, with 4 weeks in between evaluations. The control group received CPR theoretical education before the study. The data was analyzed by ${\chi}^2$-test and t-test using the SPSS/WIN 12.0 program. Results: Hypothesis 1 was that the basic CPR knowledge score would begin to decrease right after the education and continue to decrease as time passed. The experimental group's knowledge score continued to increase 12 weeks after education, but there was no decrease in the control group's knowledge score (F=5.870, p=.000). Hypothesis 2 was that the basic CPR attitude score would decrease right after the education and continue as time passed. There was no significant difference in the experimental group's score after education, nor was there any change in the control group's score on this measure (F=3.986, p=.004). Hypothesis 3 was that the subjects' confidence in practicing CPR would decrease right after education and continue as time passed. There was a significant decrease in the experimental group's score, but no significant change in the control group's score on this measure (F=75.574, p=.000). Hypothesis 4 was that the practical accomplishment evaluation score of CPR would decrease as time passed. There was a significant decrease in the experimental group's score on this measure right after education (F=38.368, p=000). Conclusion: Retraining for basic CPR education will be needed in all aspects of the education/training at least every 4 weeks, to preserve the students' retention of learned material/training. This is because students' scores fell significantly four weeks after education/training.

The Analysis and Implication of Link Integrity of Korean Public Institution Website from a Web Usability Perspective (웹 사용성 관점에서 공공기관 웹 사이트의 링크 유효성 분석 및 개선 과제)

  • Moon, Hyun Ju;Kim, Suk Il
    • 재활복지
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    • v.17 no.4
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    • pp.291-309
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    • 2013
  • Web usability is utilized as a standard for constructing and managing website to be useful by people of all abilities and disabilities. Link integrity is one of main criteria for web usability evaluation. Links that are found to be broken or pointing to irrelevant information lead gradual degradation of link integrity over time. This study has conducted investigation for link integrity of Korean public institution website. Among 49 website that are accessible by an automatic link checker software, 91.8% of the website has more than one broken links. Also average number of broken links is 50.5 that is 0.33% of the number of links. 29 websites consist of internal broken links. And 22 website do not provide any information on the missing page. Broken links enlower website confidence by reducing web usability as well as they prohibit web search engine not to provide information on the website. Therefore, web developers and managers need to be aware of importance of link integrity and prohibit web usability degradation by performing link validation as a web management task or periodically.

A Study on Early Childhood Teachers' Perception and Practice on Technology Leadership (테크놀로지 리더십에 대한 유아교사의 중요도 및 실행도 인식)

  • Jung, Ji-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.82-90
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    • 2019
  • The purpose of this study was to examine early childhood teachers' importance and performance of technology leadership. A survey was conducted on 205 early childhood teachers. Borich's needs model was used to calculate their needs. In the area of director leadership and vision, the early childhood teachers felt the most need for opportunities to participate in conferences or training programs related to the educational utilization of technology. In the area of teaching-learning methods, they called the most for better ways to take advantage of technology considering the characteristics of the activity areas and activity types. In the area of teaching professionalism, the items they asked for the most were building confidence over the educational utilization of technology and case studies of superior teaching and learning. In the area of institutional support, they felt the most need for assistant human resources who could assist in solving possible problems using technology. In the area of evaluation, they called the most for the development of a variety of evaluation tools and methods. Finally, the item they called for the most in the area of social, ethical, and legal support from the institutions to which they belonged was the preparation of guidelines on how to be in good health in times of using technology.

Exploring Factors Influencing Affective Characteristics in Elementary School Students: Focusing on School Mathematics Education and Social Environment (초등학생의 정의적 특성에 영향을 미치는 요인 탐색: 학교에서의 수학 교육 및 사회적 환경을 중심으로)

  • Kwon, Jeom-Rae;Kwon, Misun
    • Education of Primary School Mathematics
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    • v.26 no.3
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    • pp.199-217
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    • 2023
  • Affective characteristics have been consistently emphasized in mathematics education, but students' confidence or interest in mathematics has not changed significantly. This study analyzes the factors affecting the affective characteristics according to students' academic achievements, which have not been studied so far. The study was surveyed 593 students in the 5th and 6th grades, divided into school mathematics education and social-environmental factors. As a result of the study, students cited 'mathematics class at school' as the factor that had the most influence on their affective characteristics, regardless of academic achievement. Excluding 'mathematics classes at school', upper level students said that 'private education' and 'college entrance exams and jobs', had the most influence on their affective characteristics. Middle level students said that 'assessment at school' and 'private education' had the most influence on their affective characteristics. Lower-level students said that 'school evaluation' and 'mathematics textbook' had the most influence on the affective characteristics. In particular, as the academic achievement level decreased, students' participation in classes decreased rapidly. Most students said that the mathematics content they were learning was too difficult for that reason. Considering these research results, it would be effective to apply methods according to students' academic achievement to some extent in order to improve affective characteristics.

The Monitoring of some heavy metals in oriental herbal medicines and their intake rates (한약재 중 중금속의 모니터링 및 가용 섭취율 분석 연구)

  • Yim, Okkyoung;Han, Eunjung;Chung, Jaeyeon;Park, Kyungsu;Kang, Inho;Kang, Sinjung;Kim, Yunje
    • Analytical Science and Technology
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    • v.22 no.2
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    • pp.128-135
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    • 2009
  • This paper is the monitoring results of some heavy metals (lead, cadmium, arsenic, mercury) in herbal medicines and their intake rates. The monitoring of lead, cadmium, arsenic and mercury was carried out on 600 samples with 60 kinds of herbal medicines. And the transfer ratio of heavy metals in the water-boiled drinks w as calculated. The results show that lead was detected over the Maximum Residue Limits (MRL) in 10 samples (7 species). Cadmium was detected over the MRM in 69 samples (19 species). Arsenic was detected over the MRM in 3 samples (3 species). Mercury was detected over the MRM in 13 samples (10 species). We need continuously monitoring to ensure confidence and safety for these herbal medicines. In case of the water-boiled drink, average intake rates of lead, cadmium, arsenic and mercury are 9.77%, 6.72%, 26.1% and 6.79%, respectively.

Comparison of CT Volumetry and RECIST to Predict the Treatment Response and Overall Survival in Gastric Cancer Liver Metastases (위암 간전이 환자의 반응평가와 생존율 예측을 위한 종양 부피 측정과 RECIST 기준의 비교 연구)

  • Sung Hyun Yu;Seung Joon Choi;HeeYeon Noh;In seon Lee;So Hyun Park; Se Jong Kim
    • Journal of the Korean Society of Radiology
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    • v.82 no.4
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    • pp.876-888
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    • 2021
  • Purpose The aim of this study was to compare the diameter and volume of liver metastases on CT images in relation to overall survival and tumor response in patients with gastric cancer liver metastases (GCLM) treated with chemotherapy. Materials and Methods We recruited 43 patients with GCLM who underwent chemotherapy as a first-line treatment. We performed a three-dimensional quantification of the metastases for each patient. An independent survival analysis using the Response Evaluation Criteria in Solid Tumors (RECIST) was performed and compared to volumetric measurements. Overall survival was evaluated using Kaplan-Meier analysis and compared using Cox proportional hazard ratios following univariate analyses. Results When patients were classified as responders or non-responders based on volumetric criteria, the median overall survival was 23.6 months [95% confidence interval (CI), 8.63-38.57] and 7.6 months (95% CI, 3.78-11.42), respectively (p = 0.039). The volumetric analysis and RECIST of the non-progressing and progressing groups showed similar results based on the Kaplan-Meier method (p = 0.006) and the Cox proportional hazard model (p = 0.008). Conclusion Volumetric assessment of liver metastases could be an alternative predictor of overall survival for patients with GCLM treated with chemotherapy.