• 한국물환경학회지
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• 제31권1호
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• pp.49-54
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• 2015

Acute toxicity test with Daphnia magna has a variety of factors such as incubation condition of test species, food quality and proficiency of laboratory workers. Therefore, proper proficiency testing samples were required for evaluating the competence of laboratory workers. This study aims to propose some appropriate proficiency testing samples for laboratory workers of acute toxicity test with Daphnia magna. Proposed four kinds of standard samples (Sample A, B, C, and D) for proficiency testing were selected from reference materials which were recommended from Canada and USA WET(Whole Effluent Toxicity) authorities. Proposed standard samples were tested by trial application of proficiency testing, homogeneity and stability checks using repeatability test. Sample A, C and D were estimated ad the suitable candidates for proficiency test standard samples except for Sample B. In addition, Sample A was proved to be the most suitable sample.

• 품질경영학회지
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• 제45권3호
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• pp.447-462
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• 2017

Purpose: This study aims to develop distributable samples that can be used for proficiency testing to verify the ability of the testing laboratory to perform high temperature and low temperature tests. Method: In this study, the temperature-resistance characteristics of the NTC thermistor were used to develop samples. The homogeneity and stability of samples were examined according to the proficiency testing requirements. Results: Thirty samples with homogeneity and stability were developed and used for the proficiency testing. Thus, it was possible to distinguish between the test laboratories that showed satisfactory results and those that did not. Conclusion: It was the first time to develop samples that can be used for proficiency testing in high temperature and low temperature tests. and it was proved that the proficiency test program can be operated using the characteristics of NTC thermistor.

• 한국산업보건학회지
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• 제30권1호
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• pp.58-66
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• 2020

Objectives: The objective of this study was to develop formaldehyde samples for quality control (QC) and to test the applicability of proficiency analytical testing in Korea. Methods: We made formaldehyde samples with certified standard solutions (formaldehyde in water or acetonitrile) and 2,4-dinitrophenylhydrazine (2,4-DNPH)-coated silicagel tubes. Four levels of formaldehyde concentration were tested for storage stability at room temperature and at 4℃ over three months. Analytical proficiency testing was performed with four or 36 institutes. Results: Formaldehyde sample tubes were easily made through the injection of standard solutions and the average efficiencies of recovery were 95-101%. The coefficients of variation (CV) of the formaldehyde samples were 1.39-2.55%. The recovery efficiencies fell between 90% and 110% at the concentration range of 1-10 ㎍/sample over three months storage at refrigerated and room temperature. The CVs were less than 5% in the proficiency analytical testing. By adjusted proficient ranges, 64% of the results of the second proficiency analytical testing were acceptable. Conclusions: The formaldehyde samples made by injection on 2,4-DNPH-coated silicagel tubes were stable and applicable for quality control.

• Journal of Pharmaceutical Investigation
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• 제37권1호
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• pp.27-37
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• 2007

Proficiency test is an essential tool far ensuring analytical ability of analytical chemists and analytical institutes. Usually, the standard protocol for proficiency test is focused on acceptability of reported analytical results of participants by calculating z-scores and related diagnostic parameters. The ultimate goal of this process is to reveal the sources of variability of analytical results and to find the way to reduce their influence. In this study, the method of analysis of variance (ANOVA) was applied to the analytical data collected from qualify control departments of pharmaceutical companies in KyungIn province in Korea in the year of 2000. As influencing factors of variability of analytical results, the use of internal standards for liquid and gas chromatograpy, the educational and professional background of participants, geological locations and yearly production sizes of participating companies were evaluated. To evaluate the variability in accuracy of analytical results, absolute differences from sample mean and sample median were used and to evaluate variability in precision of individual participants, the reported standard deviation of each participant was used. As a result, the use of internal standards in gas chromatographic analysis, participants' academic background and the yearly production sizes of pharmaceutical companies showed statistically significant influence to the accuracy and the precision of the reported analytical results used in this study.

• 수산해양교육연구
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• 제26권3호
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• pp.597-610
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• 2014

The purpose of this study was to inquiry of influence of Meister high school and specialized vocational high school' students on career maturity in problem solving ability domain of test for enhanced employ ability & upgraded proficiency. Research subjects and region were sophomore students of each one of Meister high schools and specialized vocational high schools in Gwangju region. The sample(N=481) was drawn from 2 high schools and collected data were analyzed with SPSS using t-test, Pearson correlation and Levene's test. Items of problem solving ability domain of test for enhanced employ ability & upgraded proficiency were used test items developed in 2012. Career maturity test in Careernet site was used test items developed in 2001 which was made up 3 domains such as attitude, ability and action and 8 sub-regions such as planning, attitude on the vocation, independence, self-understanding, rational decision-making, explore of information, knowledge of hope vocation and career exploration and preparation of action, and constituted 64 items. The results were as follows. Findings of the analysis in specialized vocational high school students demonstrated the positive results of rational decision-making and explore of information in problem solving ability test for enhanced employ ability & upgraded proficiency. Comparing career maturity influence on Meister high school with specialized vocational high school students about problem solving ability domain of test for enhanced employ ability & upgraded proficiency, Meister high school students' score were more high grade than specialized vocational high school students grade.

• 수산해양교육연구
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• 제27권4호
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• pp.948-962
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• 2015

The purpose of this study was to inquiry of outcomes and challenges of Meister high school' and specialized vocational high school' teachers and industrial workers on problem solving ability domain of test for enhanced employ ability & upgraded proficiency, and what were outcomes and challenges of main factor by Meister high school and specialized vocational high school' teachers and industrial workers. Research subjects and region were teachers of Meister high schools and specialized vocational high schools in Gyeongsangnamdo and industrial workers in Gyeonggido. The sample(N=147) was drawn from Meister high school' teachers(N=90), specialized vocational high school' teachers(N=25) and industrial workers(N=32), and collected data were analyzed with SPSS using average, standard deviation, cross analysis, verification F. The results are as follows: The biggest outcomes of problem solving ability domain of test for enhanced employ ability & upgraded proficiency was change of educational direction for promoting core competency on specialized high school & Meister High School's students. The biggest positive ripple effects of the outcomes was also change of educational direction for promoting core competency on specialized high school & Meister High School's students. The biggest challenges of problem solving ability domain of test for enhanced employ ability & upgraded proficiency was importance of challenges was expansion of teacher training and lecture on the Test for Enhanced Employ ability & Upgraded Proficiency.

• 한국군사과학기술학회지
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• 제17권6호
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• pp.828-835
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• 2014

GC-TSQ CI technique was applied for analysis of samples for the $32^{nd}$ OPCW proficiency test. Eight chemical weapon convention(CWC) related chemicals were identified by product ion mode analysis with GC-TSQ in the samples. Choice of specific precursor ion made it possible to supply selective total ion chromatograms(TICs) of target molecule. GC-TSQ CI anaylsis technique was useful method for chemical warfare agent verification because analysis selectivity was improved by choice of mother molecule as precursor ion and gave mass spectra.

• 분석과학
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• 제20권1호
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• pp.78-83
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• 2007

식품 중 발기부전치료 성분 및 유사물질의 분석능력을 평가하기 위하여 실험실간 정도관리를 시도하였다. 평가대상물질은 실데나필, 타다라필, 바데나필, 호모실데나필, 하이드록시호모실데나필, 슈도바데나필 6종이었으며, 참여기관은 식품위생검사를 담당하고 있는 13개 기관이었다. 표준시료는 이중맹검을 위하여 평가대상물질 중 임의의 3종을 함유하도록 조제한 인삼음료 13개이었다. 분석방법은 식품공전의 일반시험법에 제시되어 있는 발기부전치료제 유사물질 시험법에 따라 일정량을 취하여 물에 희석한 후 유기용매로 추출하여 HPLC/UV로 분석하고 LC/MS로 확인하는 방법을 적용하였다. 분석기간은 표준시료를 수령한 날로부터 60일이었다. 검사능력관리규정에 따라 Z-값 및 RSZ를 종합평가한 결과 10기관이 만족한 수준이었다.

• 영어어문교육
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• 제15권4호
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• pp.177-197
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• 2009

This study investigated the effects of dictation practice, in terms of listening proficiency and the use of listening strategy. The research was implemented for 15 weeks with 89 freshmen and sophomores at a Korean university. The subjects were divided into an experimental group and a control group. All conditions were the same in both groups, except that the experimental group had dictation practice on a regular basis in their listening classes through one semester. For the purpose of the study, two research questions were set; 1) Does dictation practice improve listening proficiency? 2) What are the differences in the use of listening strategies between the two groups? Does dictation practice make the participants use different listening strategies? A sample TOEIC listening test was conducted as a pre-test and post-test. A questionnaire was used to find out the differences in the use of listening strategies between the two groups. The results of this study reveal that there was no statistically difference in improvement between the two groups; however, the experimental group scored much higher on the post-test than the pre-test compared with the control group. In regard to listening strategies, among 6 listening strategies, the use of metacognitive listening strategies had a significant difference between the two groups. On the basis of the results, the study suggested some guidelines for dictation practice in EFL listening classes and called for more studies on its effects.

• International Journal of Advanced Culture Technology
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• 제11권3호
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• pp.156-162
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• 2023

The purpose of this study was to examine the effects of peer scaffolding on the writing fluency of English language learners. This study was intended to confirm that peer scaffolding in English as a foreign language (EFL) writing classes can improve students' English proficiency. An analysis of 20 EFL learners studying at a university in Gyeonggi Province was conducted based on the English Proficiency Test. In this study, 20 intermediate learners with similar proficiency levels were included in the sample. Randomly, 10 students were designated as members of the control group, and 10 students were designated as members of the experimental group. In the experimental group, students practiced essay writing, while a skilled student provided scaffolding for a less skilled student. A variety of tools were used to gather data, including tests, questionnaires, and interviews Statistical analyses of quantitative data were conducted using t-tests for independent samples, whereas analyses of qualitative data were conducted based on themes. Pre-test results indicated a significant value of sig. =0.87, which was higher than α = 0.05. According to the results of this study, the writing performance of both experimental and control groups of students was equal and homogeneous prior to treatment. However, there were significant differences between the writing of students in the two groups after the completion of the program. Due to the post-test analysis of the writing test, the test resulted in a sig. =0 .043, a value lower than α = 0.05. As a result, the experimental group participants showed a marked improvement in their writing abilities after treatment.