• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.81-85
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• 1973

One hundred and thirty one health articles (as 'original articles') reported in medical journals published in Korea during the period from Jan. to Dec. 1971. were selected as the study materials for tile purpose of resumption and criticism. Of a total of 131 articles, thirty-nine were not required the statistical application for the data processing and drawing their conclusions and ninty-two, 70.2%, were needed to apply. The 92 articles were divided into three groups by the types of study: 54 for experimental study, 30 for clinical case analytic study and 8 for field study. Each report was resumed and criticised under the statistical aspects in terms of data processing and the validity of the conclusions. The results of resumption of the 92 articles needed statistical application are summarized as follow; 1. Of the 54 articles of experimental studies resumed, thirty-one articles, 57.4%, were considered acceptable. Among the 38 articles classified as clnical case analytic and field studies, only 28.9 per cent were considered acceptable. In total 45.7 per cent or less than half were considered acceptable. 2. Types of errors encountered are as shown in Table 3. 3. The most frequently encountered error was that the conclusions were drawn without having made any statistical test. This type of error was found in 14 out of 35 errors presented in experimental studies, 11 of 35 in clinical case analytic studies and 5 of 9 in field studies and 30 out of 97, 38.2%, in total.

• Journal of Environmental Health Sciences
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• v.49 no.2
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• pp.57-65
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• 2023

Background: The association between exposure to extremely low frequency-magnetic fields (ELF-MF) and childhood leukemia has been controversial. There is a need to clarify this relationship by summarizing key conclusions from systematic review articles. Objectives: The major aim of this study is to summarize key conclusions from systematic review articles on the association between exposure to ELF-MF and childhood leukemia based on childhood exposure to ELF-MF, proximity from childhood household to high voltage cables, and parental occupational exposure to ELF-MF. Methods: This study was conducted through a brief literature review focusing on systematic, meta-analysis, and pooled analysis methods. We conducted a literature search in PubMed using the key words "ELF-MF" and "childhood leukemia" singly or combined. Results: In 2002, the World Health Organization (WHO)'s International Agency for Research on Cancer (IARC) reviewed two manuscripts to conduct pooled analysis and concluded that there is a significant association between exposure to >0.3 μT or 0.4 μT and childhood leukemia. We found a total of four manuscripts for systematic or pool analysis that have been published since the IARC's conclusion. They consistently concluded that there was a significant association between exposure to >0.4 μT and childhood leukemia compared to ELF-MF exposure to below 0.1 μT. The proximity of children's households to high voltage cable lines and occupational exposure by their parents to ELF-MF during certain periods prior to or during pregnancy were inconsistently associated with childhood leukemia. The study found that many EU countries have implemented precautionary policies to prevent potential childhood leukemia due to exposure to ELF-MF. Conclusions: This study recommends implementing a precautionary policy that includes legal exposure limits for ELF-MF to minimize exposure to ELF-MF.

• Journal of the Korean Chemical Society
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• v.67 no.2
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• pp.106-115
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• 2023

The purpose of this study was to investigate the errors in science inquiry research reports written by students who won the encouragement award at the National Science Fair, and analyze the frequency of error types by school levels. The framework for analysis was constructed based on the table of contents of the students' science inquiry research reports, and the reports were analyzed for errors in six stages: Research question/hypothesis, prior research, experimental procedure, results, conclusions, and references. The study identified several types of errors at each stage, such as unreasonable research questions and wrong hypotheses in the research question/hypothesis stage, and limited considerations under certain conditions and selection of inappropriate experimental instruments in the experimental procedure stage. The study found that the frequency ratio of experimental procedure error was the highest across all school levels, and the order of errors varied by school level. Frequency ratio of error types of school level was: in the elementary school students' reports, errors were analyzed in the order of experimental procedure (36.88%), prior research (17.02%), conclusions (16.31%), research question/hypothesis (13.48%); In the middle school students' reports, experimental procedure (42.86%), conclusions (20.00%), prior research (14.28%), results (11.43%), research question/hypothesis (10.01%); In the high school students' reports, experimental procedure (45.16%), research question/ hypothesis (16.13%), conclusions (16.13%), and prior research (11.83%). The findings could be used to guide teachers in helping students conduct scientific inquiry research or write reports.

• The Journal of the Korean dental association
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• v.24 no.2 s.201
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• pp.143-152
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• 1986

The soft tissue profiles of 56 normal children were studied on their cephalograms and follow ing conclusions were made. 1. Upper facial height, Lower facial height, lower lip length were longer in female. 2. Facial convexity including the nose was convex in female. 3. Nasolabial angle, columella facial angle were larger in female. 4. Standard deviation wiggle grams were made.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.48.5-48
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• 2002

$\textbullet$ Contents 1 Introduction $\textbullet$ Contents 2 Crane Description $\textbullet$ Contents 3 Self-tuning Controller Design $\textbullet$ Contents 4 Result of Experiments $\textbullet$ Contents 5 Conclusions $\textbullet$ Contents 6 References

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.83.1-83
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• 2002

$\textbullet$ Introduction $\textbullet$ Control System Structure $\textbullet$ Coefficient Diagram Method $\textbullet$ Controller Design $\textbullet$ Experimental Results $\textbullet$ Conclusions

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.83.2-83
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• 2002

1. Introduction 2. Twin-Drive Geared Mechanical System 3. Reduced-Order Control Model 4. Model-Based Control System 5. Suppression of Transient Vibration 6. Effects of Model-Based Control 7. Conclusions

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.101.2-101
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• 2002

$\textbullet$ Introduction $\textbullet$ Preprocessing $\textbullet$ Pattern Recognition $\textbullet$ Post Processing $\textbullet$ Calibration and Coordinate Transformation $\textbullet$ Experiments and Result $\textbullet$ Conclusions

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.60.5-60
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• 2002

$\textbullet$ Introduction $\textbullet$ Bilinear system model $\textbullet$ Design of sliding control and stability analysis $\textbullet$ Design of proposed controller $\textbullet$ Simulations $\textbullet$ Conclusions $\textbullet$ References

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.34.4-34
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• 2002

1. Introduction 2. Basic Camera models and geometry 3. Projection of line widths 4. Camera calibration algorithm 5. Experimental results 6. Conclusions and future work