• Communications of Mathematical Education
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• v.22 no.3
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• pp.369-382
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• 2008

We discuss the effect of ability grouping calculus courses based upon student's proficiency of the subject and their collective examination of midterms and finals among mid-level and low-level classes. We assess incoming freshmen at Seoul National University of Technology(SNUT) of their proficiency in calculus and assign them to the appropriate levels within the course(i.e., high-level, mid-level, low-level). We found that this was beneficial to both students and instructors. Instructors can easily determine the pace in which each class should be kept, and students can quickly adapt to the learning environment.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.149-155
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• 2023

Since developing digital technology requires new skills in digital literacy, digital competence also has become a keystone in English classes. This study explores three aspects of English as a Foreign Language (EFL) learners' digital confidence: information and data literacy, communication and collaboration, and digital content creation, based on the European Digital Competence Framework for Citizens (DigComp). The participants were 150 Korean college students enrolled in two general English classes, and their English proficiency levels were from basic to advanced; each level consisted of 30 participants. In order to assess their digital confidence, I designed a Google survey form and collected data during two semesters. The survey results revealed that the participants had highest digital confidence in information and data literacy and overall, the female participants showed higher digital confidence than their male counterparts. It also showed that the learners' English proficiency and computer skills are important factors.

• Analytical Science and Technology
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• v.23 no.3
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• pp.284-294
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• 2010

In this study, river water-based reference materials (RMs), NIER-I08RW and NIER-I09, for trace metal analysis were prepared and certified for Pb, Cd, Cr and Cu with evaluation of uncertainties. The RMs were confirmed to be homogeneous enough to be used as proficiency testing materials since within-bottle homogenieties of the RMs were lower than 0.3 times of targeted standard deviation of proficiency testing. The RMs were distributed to environmental testing laboratories for the proficiency testing and the variation of Z scores of the proficiency testing results were compared for different assigned values. The relative bias, $B_{relative}$, deviations between reference values and consensus values, were lower than ${\pm}$1 except for cadmium of NIERI08RW. The results showed both values were in a good agreement and only 2.9% of Z scores changed by using a different assigned values such as consensus and reference values.

• Analytical Science and Technology
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• v.14 no.3
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• pp.230-237
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• 2001

In general, the pH measurement follows calibration of glass electrode system using pH standard solution. When pH is measured at constant temperature, uncertainty factors are mainly related to the accuracy of pH standard solution and the accuracy and precision of glass electrode. Participants in this proficiency test were the volunteers trying to know the distribution of the measured pH values for the same sample and the sources of error through 1998 and 1999. The samples for proficiency test are phosphate salt standard solutions specially prepared in KRISS, of which pH values were 6.860, 7.415(at $25^{\circ}C$), and the stability test was performed for the same periods of proficiency test. The results of the proficiency test were plotted according to Youden plot, which shows whether the error is random or systematic. The results of Youden plot showed that the source of error was from the systematic effect of laboratories in each year. This shows that the source of error is the standard solutions used in laboratories.

• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.105-113
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• 2017

KOLAS (KOrea Laboratory Accreditation Scheme) belongs to APLAC (Asia Pacific Laboratory Accreditation Cooperation). KOLAS manages the accreditation scheme for measurement traceability to SI units. As per June 2016, there are 22 KOLAS laboratories for liquid flow metering. Among them, 12 laboratories participated in the proficiency test (PM2015-08) for water flow metering, organized by KASTO (Korea Association of Standards and Testing Organizations). This proficiency test was performed with three kinds of flow ranges ($3.6m^3/h{\sim}12m^3/h$, $40m^3/h{\sim}80m^3/h$, $40m^3/h{\sim}200m^3/h$) considering the CMC (calibration and measurement capability) of the participating laboratories. The purpose of the proficiency test was to find out measurement equivalence of the CMC's between each participating laboratory and the reference testing laboratory (KRISS). The measurement equivalence was tested by the number of equivalence ($E_n$). If ${\mid}E_n{\mid}$ < 1, the measurement equivalence was established. All the participating laboratories passed this proficiency test.

• Analytical Science and Technology
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• v.22 no.1
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• pp.82-91
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• 2009

Preparation and evaluation of the limestone samples for a proficiency test using domestic limestone have been performed. We have used statistical method for evaluation of the XRF and instrumental analysis results. We have found that there were some outliers from XRF and ICP-OES instrumental analysis results for each sample. After removal of 5 outliers among the 50 samples we could obtain the homogeneous samples which have within a reliability of 95% from a statistical analysis result.

• Analytical Science and Technology
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• v.27 no.6
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• pp.339-346
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• 2014

The author assessed the availability of urine reference material for proficiency test provided for laboratories in occupational health. N-methylacetamide is the biomarker of exposure to N,N-dimethyl acetamide, which was used as the substitute for hepatotoxic N,N-dimethylformamide (DMF). N-methylacetamide (NMAC) urine samples of 3 different levels covering the 0.2~2 times of the exposure limit were tested. Stability test up to 180 days (0, 7, 30, 60, 180 days) at 4 different temperatures (-60, -20, 5, $25^{\circ}C$) and homogeneity test were performed for these samples. New analytical condition by GC/MSD using SIM mode (m/z 58, 59) and DB-624 column was investigated for better selectivity, sensitivity and resolution. Urinary NMAC samples showed good homogeneity for 3 levels. These samples also showed good stability up to 180 days. The data of stability and homogeneity of urinary DMAC confirmed the basis of including this item into Korean proficiency test for occupational health laboratories since 2008.

• Journal of Korean society of Dental Hygiene
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• v.15 no.1
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• pp.19-29
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• 2015

Objectives: The purpose of the study is to investigate the related factors to dental care utilization, oral health behaviors, and oral health status in immigrant workers in Korea. Methods: The subjects were 504 foreign immigrant male workers over 20 years old who visited Daegu labor consultation center for oral health survey and oral examination. The questionnaire included 5 questions of socioeconomic characteristics, 8 questions of oral health practice behavior, 6 questions of dental clinic visit, 8 questions of social relations and Korean language proficiency. The question for health behavior was measure by body mass index(BMI). Social relations and Korean language proficiency instrument was modified by Seol from "Family welfare survey in Korean international marriage" and scored by Liker 5 scale. Results: The oral health examination of the immigrant workers was as follows: decayed teeth - 76.6%, filling teeth - 27.4%, missing teeth - 69.8%, dental caries experience above five or more - 60.2%, periodontal pocket tissues - 58.9%. Simplified Oral Hygiene Index was very poor and accounted for 49.0%. Dental care utilization experience was closely associated with social relation indexes including attendance in family events, household stuff help, financial help and counseling for hard work(p<0.01). Dental care utilization experience proportionally increased with proficiency in Korean literacy including speaking, listening, and writing abilities of Korean language(p<0.01). Conclusions: In order to improve the oral health condition of the immigrant workers, it is important to provide social network, Korean language proficiency support, and health insurance coverage through economic burden reduction by the Korean government.

• Korean Journal of Environmental Agriculture
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• v.35 no.3
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• pp.223-233
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• 2016

BACKGROUND: This study was to develop a analytical reference material including twenty pesticides in tomato. To use it for proficiency test, the suitability of homogeneity, storage stability, assigned values and uncertainty for analytical reference material were important.METHODS AND RESULTS: In order to develop a analytical reference material of tomato for multi-residue analysis of pesticides, twenty-pesticides were treated in tomato and the samples were frozen and homogenized. The homogeneity, stability, assigned value and uncertainty were calculated according to the requirements of the KS A ISO Guide 35, KS Q ISO 13528 and EURL-PT protocol. The values of the within-bottle standard variation(s_wb) and the between-bottle standard variation(s_bb) were 0.9~6.5% of assigned value and the uncertainty(u*_bb) due to inhomogeneity was also calculated as 0.6~1.9% for all pesticides. This indicated that it was satisfactory to be used as a analytical reference material. The storage stabilities of twenty-pesticides at room temperature and freezing conditions were assessed according to the requirement of the KS Q ISO Guide 35. All pesticides were stable at room temperature (20~30℃) for 8 days and freezing (-20℃) for 23 days.CONCLUSION: The feasibility of analytical reference material for pesticide multi-residue analysis in a tomato matrix was investigated. Homogeneity of within/between-bottle, uncertainty and stabilities at room temperature and freezing condition were satisfactory for a use of proficiency test and quality control. From these results, a analytical reference material would be applicable to monitor the proficiency test of pesticide analysis organizations to improve the reliability and consistency.

• MALSORI
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• no.57
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• pp.31-42
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• 2006

The purpose of this study is to observe how Korean learners perceive an English weak syllable in words containing WS syllable pattern. According to the automated discrimination task using E-Prime, the ratio of correct answer(%) and reaction time of the stimuli with same syllable patterns were respectively higher and faster than those with different syllable patterns. Specifically, in the stimuli with different syllable patterns, the frequency(familiarity) of stressed word succeeding weak syllable and whether the weak syllable had coda in it were two important factors in distinguishing between a word with and without weak syllable. Even though the high English proficiency Koreans had faster reaction time than the low English proficiency Koreans, all Korean learners had a difficulty in perceiving the weak syllable at the beginning of a word.