• Journal of The Korean Association For Science Education
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• v.12 no.1
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• pp.93-101
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• 1992

The purposes of this study were; 1) to apply the network analysis to evaluation of students' laboratory reports, 2) to test the applicability of the systematic network analysis. For this purposes, 7th grade 88 students from 22 middle schools in Inchon city of Korea were selected and their laboratory reports were evaluated by a evaluation criterion network developed in this study. The evaluation criterion consisted of 4 categories and 10 subcategories. The results of this study suggested that the network analysis approach was suitable one for the evaluation of students' laboratory reports. This was supported by total score distribution, means/weight, Cronbach's ${\alpha}$ coefficient(0.70), and the subcategories' reliabilities. The resluts of the factor analysis indicated that the evaluation criterion network of this study had two factors.

• Journal of The Korean Association For Science Education
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• v.28 no.6
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• pp.633-640
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• 2008

In this study, we investigated the possibility of using science laboratory reports in identifying students' ideas about discrepant events. A specially designed science laboratory report was developed in this study, and used to collect the information about students' responses toward discrepant events. A total of 839 laboratory reports on the solubility of gas, combustion, and the electrical conductivity of a solution were analyzed. Students' responses in the laboratory reports were classified into eight types; rejection, reinterpretation, exclusion, uncertainty, peripheral theory change, theory change, maintenance of scientific conception, and regressive theory change. In addition, reinterpretation and theory change were further classified into several subcategories. The characteristics of students' responses in this study were discussed in comparison with those of previous studies.

• Journal of Science Education
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• v.36 no.2
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• pp.303-312
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• 2012

This study was to find science high school students' perception about composing laboratory reports by grade. The instrument to survey the perception of them consisted of the perception about making a lab report, and the effect of compositing laboratory reports on the scientific concept understanding and the scientific inquiry ability. Subjects were 260 students of four science high schools in Seoul metropolitan city and Kyounggi province. Most of science high school students had a little positive perception about compositing lab reports, but they had very positive perception about the effects of it on the scientific concept understanding and scientific inquiry ability. There was the significant difference between grades, because the 10th grade students showed more positive perception toward compositing lab reports than the 11th graders(p<.05). The results suggested that different educational approaches and teaching strategies be needed for science high school students considering grades.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.189.2-190
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• 2003

Methylmercury (MeHg), one of the heavy metal compounds. can cause severe damage to the central nervous system in humans. Many reports have shown that MeHg is poisonous to human body through contaminated foods and has released into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established so far. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.153-153
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• 2002

Methylmercury (MeHg), one of the heavy metal compound, can cause severe damage to the central nervous system in humans. Many reports have contributed MeHg poisoning to contaminated foods and release into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established.(omitted)

• BMB Reports
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• v.55 no.7
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• pp.360-360
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• 2022

• Journal of The Korean Association For Science Education
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• v.29 no.8
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• pp.848-860
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• 2009

This study examined the characteristics of scientists' writing on the laboratory reports written in the authentic open inquiry, and explored the possibility that the class discussion after the inquiries could influence the laboratory report writing. The samples were 131 10th graders in a science high school in Seoul. The control group (n=45) practiced traditional school science inquiries, the experimental group 1 (n=43) practiced the authentic open inquiries, and the experimental group 2 (n=43) practiced the authentic open inquiries and the class discussion after the laboratory activities. Their laboratory reports were analyzed into three parts - prediction (prediction with background and apposite description), data analysis (data transformation and critical analysis), and conclusion (objective description based on evidence). The frequency of the characteristics of scientist's writing in the experimental group was higher than the control group. Particularly, the differences of the prediction with background (p<.01) and the critical analysis of data (p<.05) were statistically significant. However, the frequency of writing the conclusion based on evidence was very low in all of the three groups. The result from comparing descriptions of reports showed that the writing prediction in experimental groups were more elaborate, and the data transformation in experimental groups were more correct, and the evaluation to data in experimental groups were more critical than the control group. And the descriptions of the critical evaluation to data and the finding flaw in methods were found in experimental groups 2, indicating that the class discussion can stimulate students' scientific thinking.

• BMB Reports
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• v.41 no.9
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• pp.670-677
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• 2008

A cDNA microarray composed of 2,028 different ESTs from two shrimp species, Penaeus monodon and Masupenaeus japonicus, was employed to identify yellow head virus (YHV)-responsive genes in hemocytes of P. monodon. A total of 105 differentially expressed genes were identified and grouped into five different clusters according to their expression patterns. One of these clusters, which comprised five genes including cathepsin L-like cysteine peptidase, hypothetical proteins and unknown genes, was of particular interest because the transcripts increased rapidly ($\leq$ 0.25 hours) and reached high expression levels in response to YHV injection. Microarray data were validated by realtime RT-PCR analyses of selected differentially expressed transcripts. In addition, comparative analysis of the hemocyte transcription levels of three of these genes between surviving and non-surviving shrimp revealed significantly higher expression levels in surviving shrimp.

• Journal of The Korean Association For Science Education
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• v.31 no.1
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• pp.115-127
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• 2011

Analysis frame for undergraduate physics laboratory reports in collecting, processing, and analyzing data was developed. Using the frame and questionaries, we analyzed what difficulties students have in the concepts of error and uncertainty in writing laboratory reports. Students considered repetitive measurement for collecting data, but they didn't express it distinctly in their reports. They also had difficulties in measuring data around the extreme value or the large slope. Especially, most students have had difficulties with error and uncertainty. They can't apply the basic formulation to propagation of error and uncertainty. They also had the difficulties in analyzing data with concepts of error and uncertainty. While most students responded that error and uncertainty is important, there were few students who analyzed the influence of the cause of error on the results quantitatively. The result of the study showed that students have difficulties in writing the laboratory reports because they didn't have the correct concept of the error and uncertainty. So, it is needed to not only teach the physics concept about experiment but to teach basic concept of data collecting, processing, and analyzing specially about error and uncertainty for students as well.

• Current Optics and Photonics
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• v.5 no.1
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• pp.59-65
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• 2021

This paper reports a tunable diode-pumped folded intracavity Q-switched singly resonant optical parametric oscillator based on multi-period MgO:PPLN. A wide tuning mid-infrared parametric light from 2.78 ㎛ to 4.17 ㎛ was obtained in real time by changing the poled periods and temperatures. The maximum output power of 1.89 W at 3.2 ㎛, 1.53 W at 3.5 ㎛, 0.87 W at 3.8 ㎛ and 0.486 W at 4.1 ㎛ were achieved. The highest optical-optical conversion efficiency was 7.89%. During experiments, a range tunable output of 2.78-4.17 ㎛ in the mid-infrared range was achieved.