• Bulletin of the Korean Chemical Society
• /
• v.19 no.11
• /
• pp.1227-1232
• /
• 1998

The frequency response on the tip-sample distance in scanning electrochemical microscopy (SECM) that is combined with an electrochemical quartz crystal microbalance (EQCM) is described. The oscillation frequency of the EQCM increases rapidly when the SECM tip is very close to the substrate electrode surface. This frequency increase is reproducible regardless of the current feedback in SECM, which is attributed to the stress caused by the tip pressing the quartz crystal. It is useful to calibrate the tip-sample distance with respect to the frequency change when a combined system of SECM and EQCM (SECM-EQCM) is used. This method could be applied to several cases such as rigid metal electrode and non-conducting or partially conducting polymer coating prepared on the quartz crystal regardless of the feedback current.

• Restorative Dentistry and Endodontics
• /
• v.49 no.1
• /
• pp.3.1-3.8
• /
• 2024

This article is a narrative review that discusses the recommended sample size requirements to design a pilot study to assess the reliability of a questionnaire. A list of various sample size tables that are based on the kappa agreement test, intra-class correlation test and Cronbach's alpha test has been compiled together. For all calculations, type I error (alpha) was set at a maximum value of 0.05, and power was set at a minimum value of 80.0%. For the kappa agreement test, intra-class correlation test, and Cronbach's alpha test, the recommended minimum sample size requirement based on the ideal effect sizes shall be at least 15, 22, and 24 subjects respectively. By making allowances for a non-response rate of 20.0%, a minimum sample size of 30 respondents will be sufficient to assess the reliability of the questionnaire. The clear guideline of minimum sample size requirement for the pilot study to assess the reliability of a questionnaire is discussed and this will ease researchers in preparation for the pilot study. This study provides justification for a minimum requirement of a sample size of 30 respondents specifically to test the reliability of a questionnaire.

• Korean Management Science Review
• /
• v.33 no.3
• /
• pp.65-87
• /
• 2016

Being the FinTech technologies rapidly developed, the non face-to-face private loan market is also growing dramatically. While the real-world interests in this market are keen, the empirical studies on the issue are few compared to its prospective impact on credit loan market. This paper suggests a credit scoring model for the non face-to-face private loan employing the ratings approach (the absolute measurement method) of AHP. Analyzing a sample of data consisting of 460,000 transaction records over an 8-year period in the United States, we develop a scoring model for the non face-to-face private loan screening, and validate the model for the practical usage. Conducting sensitivity analysis, we suggest customized cut-off points for the loan execution to suit each individual loan institution's need.

• Journal of radiological science and technology
• /
• v.44 no.6
• /
• pp.679-688
• /
• 2021

This study is a questionnaire about the lesson environment that radiation major students prefer in a non-face-to-face live online lesson environment for a total of 133 students, 65 second graders and 68 third graders who are enrolled in the department of radiology at a university located in the Seoul metropolitan area. And checked the satisfactory level by grade. The questionnaire consists of three categories: 1st real-time non-face-to-face lectures, 2nd professor lectures, and 3rd corona lectures. A total of 14 questions, with multiple choice and descriptive response methods. As an evaluation method, in the case of a multiple-choice question, the average was calculated using a 5-point Likert scale. As a result of conducting the independent sample T-test of the SPSS program, the response by grade was P > 0.05, and no significant result was shown by the contents of the questionnaire survey of the second grade. As for the lecture method of the department of radiology after the end of Covid-19 virus, it is better to promote face-to-face lessons in radiation training subjects and non-face-to-face real-time education in subjects centered on radiation theory.

• The Journal of Asian Finance, Economics and Business
• /
• v.9 no.5
• /
• pp.507-518
• /
• 2022

This study aimed to measure the monetary and non-monetary effects on brand awareness at hypermarkets in Riyadh. The independent variable consists of three sub-variables: price reductions, free samples, and purchasing vouchers. The research population has all Saudi and non-Saudi buyers in Riyadh. The figures show that the population size reached 3.87 million in 2019. The proportional stratification sampling technique and the recommended sample size were 387 buyers. The five-point Likert scale with the fully structured questionnaire was used. The study concldes the effect of free samples on brand awareness while there was no effect of monetary instruments. The results show that the three sales promotion incentives (price reduction, free samples, and purchasing vouchers) moderately affected brand awareness and a key role in explaining consumer behavior, so the significant impact was proved. In summary, this study showed that price reductions have the power of creating the perception of buyers at hypermarkets in Riyadh. Non-cash instruments were more effective than cash instruments in enhancing brand awareness at the hypermarkets in the Saudi market. So, the price reductions and purchasing vouchers have less power in conducting communication-based awareness. Building awareness and improving brand image through free samples were most visible in communication strategy.

• Mass Spectrometry Letters
• /
• v.3 no.1
• /
• pp.25-28
• /
• 2012

Paint Spray is developed as a direct sampling ionisation method for mass spectrometric analysis of additives in polymer-based surface coatings. The technique simply involves applying an external high voltage (5 kV) to the wetted sample placed in front of the mass spectrometer inlet and represents a much simpler ionisation technique compared to those currently available. The capabilities of Paint Spray are demonstrated herein with the detection of four commercially available hindered amine light stabilisers; TINUVIN${(R)}$770, TINUVIN${(R)}$292, TINUVIN${(R)}$123 and TINUVIN${(R)}$152 directly from thermoset polyester-based coil coatings. Paint Spray requires no sample preparation or pre-treatment and combined with its simplicity requiring no specialised equipment makes it ideal for use by non-specialists. The application of Paint Spray for industrial use has significant potential as sample collection from a coil coating production line and Paint Spray ionisation could enable fast quality control screening at high sensitivity.

• Geomechanics and Engineering
• /
• v.35 no.4
• /
• pp.437-447
• /
• 2023

The failures of tailing dams have caused irreparable damage to human lives, assets and environment and this has ultimately resulted in great economic, social and environmental challenges worldwide. Due to this, investigation into mechanical behaviour of tailings has received some attention. However, the knowledge and understanding of mechanics of behaviour in iron tailings is still limited. This study investigates the mechanics of iron tailings from Nigeria considering grading, effects of fabric resulting from different sample preparations and the possibility of non-convergent behaviour. This was achieved by conducting series of one-dimensional compression tests in conjunction with index, microstructural, chemical and mineralogical tests. The materials are predominantly poorly graded, non-clayey and non-plastic. The tailings are characterised by angular particles with no obvious particle aggregations and dominated by silicon, iron, aluminium, haematite and quartz. The compression paths do not converge and unique normal compression lines are not found and this is an important feature of the transitional mode of behaviour. The behaviour of these iron tailings therefore depends on initial specific volume. The preparation methods also have effect on the compression paths of the samples. The gradings of the samples have an influence on the degree of transitional behaviour but the preparation methods do affect the degree of convergence. The transitional mode of behaviour in these iron tailings investigated is very strong.

• Journal of Technologic Dentistry
• /
• v.42 no.4
• /
• pp.379-387
• /
• 2020

Purpose: This study aimed to explore methods to improve the quality recognition and satisfaction level of non-face-to-face lectures among students in the departments of dental technology and dental hygiene. Methods: This survey was conducted to assess the status and preference of non-face-to-face lectures and the level of awareness and satisfaction regarding the quality of these lectures among 179 students of dental technology and 295 students of dental hygiene. Statistical analyses were performed using frequency analysis, independent sample t-test, one-way ANOVA (post-hoc Duncan), Welch analysis (post-hoc Games-Howell), and hierarchical multiple regression analysis. Results: Factors that affected the ability to assess the quality of non-face-to-face lectures were the department, the method of non-face-to-face lectures, the most preferred method for conducting lectures, the level of awareness regarding the quality of face-to-face lecture, and satisfaction level. It has 71.5% explanatory power. Moreover, factors that influenced the satisfaction level of non-face-to-face lectures included the department, grade, the highest satisfied non-face-to-face teaching method, the most effective theoretical non-face-to-face teaching method, the most preferred teaching methods, and the ability to assess quality of face-to-face lectures. It has 46.8% explanatory power. Conclusion: Non-face-to-face classes should be designed and developed for web-based programs to improve the motivation and achievement level of the students and encourage interaction between the professors and students. Our findings suggest that educators should strive to achieve optimal educational effects by efficiently combining face-to-face and non-face-to-face lectures.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.7 no.1
• /
• pp.231-246
• /
• 1994

A major problem for information retrieval research in the past three decades has been methodology, even though some progress has been made in obtaining useful results from methodologically sound experiments. Within a methodology, potential problems include artificial data generated by the researcher, small sample size interpretation of findings. Critics have pointed out that some room exists for improving methodology of information retrieval research; using existing data, having big enough sample size, including large numbers of search queries, introducing more control in relation to variables, utilizing more appropriate performance measures, conducting rests carefully and evaluating findings properly. Relevance judgments depend entirely on the perception of the user and on the situation of the moment. In an experiment, the best judge of relevance is a user with a well defined information need. Normally more than two categories for relevance judgments are desirable becase there are degrees of relevance. In experimental design, careful control of variables is meeded for internal validity. When no single database exists for comparison, existing operational databases should be used cautiously, Careful control for the variations of search queries, inter-searcher sonsistency, intra-searcher consistency and search strategies is necessary. Parametric statistics requiring rigid assumptions are not appropriate in information retrieval research and non-parametric statistics requiring few assumptions are necessary. Particularly, the sign test and the Wilcoxon test are good alternatives.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.3
• /
• pp.763-768
• /
• 2024

This study utilized Q methodology to analyze subjectivity and understand the various factors contributing to the employment difficulties faced by college students majoring in digital content, particularly focusing on practical education. The original data was obtained by administering a Q sample, designed around employment stress and job anxiety, to a purposively selected P sample of 31 individuals, who sorted and classified the statements. The analysis yielded four distinct types: 'lack of practical experience,' 'lack of employment and practical skills,' 'impaired career decision-making and weak will,' and 'lack of mentors and employment information.' Based on these types, the study suggests several implications and solutions, including facilitating student participation in internship programs, offering induction and non-curricular program education, conducting career exploration workshops, and expanding senior mentoring opportunities.