• Journal of The Korean Association For Science Education
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• v.37 no.6
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• pp.971-980
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• 2017

In this study, we explored the characteristics of instrumental genesis in high school students' scientific inquiries. Twenty-three 10th to 11th graders in a science research club participated in this study. The students in 6 groups autonomously planned and performed their own scientific inquiries for one semester. Their activities were videotaped and recorded. Semi-structured interviews were conducted. Material request papers and group worksheets were also collected for analysis. The results of the study suggested that students' practices were categorized as instrument genesis. When instrument genesis did not occur, the cases at the beginning of and during the practice were described respectively. Instrumental genesis was found to appear in three categories: instrumentation; instrumentation and instrumentalization; and instrumentalization. The characteristics and details of case represented in each category were described and discussed related to affordance as the results of the study. On the bases of the results, the implications for the reconsideration of the instruments in school science inquiries are discussed.

• School Mathematics
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• v.10 no.2
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• pp.297-317
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• 2008

This study was designed to gain insight to adopt CAS into secondary level algebra education in Korea. Most inactive usage of calculators in math and most negative effects of calculators on their achievements of Korean students were shown in International studies such as TIMSS-R. A comparative study was carried out with consideration of mathematical backgrounds and technological environments. 8 Korean students and 26 US students in Grade 11 were participated in this study. Subjects' Problem solving process and their strategies of CAS usage in classical Box-problem with CAS were analyzed. CAS helped modeling by providing symbolic manipulation commands and graphs with students' mathematical knowledge. Results indicates that CAS requires shifts focus in algebraic contents: recognition of decimal & algebraic presentations of numbers; linking various presentations, etc. The extent of instrumentation effects on the selection of problem solving strategies among Korea and US students. Instrumentation

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1684-1699
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• 2017

The deblocking filter (DF) reduces blocking artifacts in encoded video sequences, and thereby significantly improves the subjective and objective quality of videos. Statistics show that the DF accounts for 5-18% of the total decoding time in high-efficiency video coding. Therefore, speeding up the DF will improve codec performance, especially for the decoder. In view of the rapid development of multicore technology, we propose a parallel DF scheme based on a modified order of accessing the coding tree units (CTUs) by analyzing the data dependencies between adjacent CTUs. This enables the DF to run in parallel, providing accelerated performance and more flexibility in the degree of parallelism, as well as finer parallel granularity. We additionally solve the problems of variable privatization and thread synchronization in the parallelization of the DF. Finally, the DF module is parallelized based on the HM16.1 reference software using OpenMP technology. The acceleration performance is experimentally tested under various numbers of cores, and the results show that the proposed scheme is very effective at speeding up the DF.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.334-339
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• 1994

In this work, we propose a planar three degree-of-freedom parallel mechanism as another type of assembly device which utilized joint compliances. These joint compliances can be adjusted either by properly replacing the joint compliances or by actively controlling stiffness at joints, in order to generate the desired operational compliance characteristics at RCC point, The operational compliance matrix for this mechanism is explicitly obtained by symbolic manipulation and its operational compliance characteristics are examined, it is found that the RCC point exists at the center of the workspace when the mechanism maintains symmetric configurations. Compliance characteristic and its sensitivity of this mechanism is analyzed with respect to the magnitude of the diagonal compliance components and two different matrix norms measuring compliance sensitivity. It is expected that the analysis results provide the designer with a helpful information to determine a set of optimal parameters of this RCC mechanism.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.5
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• pp.441-449
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• 2021

Background: The efficacy of local anesthesia decreases in patients with symptomatic irreversible pulpitis. Therefore, it was proposed that the use of premedication with an anti-inflammatory drug might increase the success rate of pulpal anesthesia in mandibular posterior teeth with vital inflamed pulp. Methods: One hundred thirty-four patients who were actively experiencing pain willingly participated in this study. The Heft Parker (HP) visual analog scale (VAS) was used to record the initial pain intensity. Patients were randomly allocated to receive a placebo, 10 mg of ketorolac, and 650 mg of paracetamol. The standard inferior alveolar nerve block (IANB) was administered to all patients using 2% lidocaine with 1:200,000 adrenaline after one hour of medication. After 15 min, the patient was instructed to rate the discomfort during each step of the treatment procedure, such as access to remaining dentin, access to the pulp chamber, and during canal instrumentation on the HP VAS. IANB was considered successful if the patient reported no or mild pain during access preparation and instrumentation. Moderate or severe pain was classified as a failure of IANB and another method of anesthesia was used before continuing the treatment. Results: The rate of successful anesthesia in the placebo, paracetamol, and ketorolac groups was 29%, 33%, and 43%, respectively, and no statistically significant difference was found between the groups. Conclusion: Preoperative administration of paracetamol or ketorolac did not significantly affect the success rate of IANB in patients with irreversible pulpitis. No significant difference was observed between the paracetamol and ketorolac groups.

• Journal of the Korea Safety Management & Science
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• v.24 no.2
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• pp.33-39
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• 2022

In order to improve the implementation of safety and health education at the site for industrial accident prevention activities, research was conducted to minimize inconvenience and increase utilization by redesigning and developing existing education methods. To date, occupational safety and health education has been conducted without considering the general work characteristics and functional facilities (mechanical, electrical, instrumentation, chemical) of workers (mechanical: turbine, valve, pump, hydraulic system, electrical: generator, breaker, motor, etc.). In particular, plant facilities were classified as mechanical and electrical facilities to improve the methodology for industrial safety and health education for plant maintenance workers. In addition, the "One Page Education Plan" was announced as a learning case because the spread of COVID-19 infectious diseases made it impossible to reduce or control the number of people in all groups and groups. The improvement of this training method will play a major role in improving the effectiveness of safety education in power plant workplaces.

• Korean Journal of Child Studies
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• v.31 no.5
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• pp.131-149
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• 2010

The purpose of this study was to examine research trends in articles of preschooler peer relationships carried in domestic academic journals. This was done in an attempt to suggest alternative directions for peer relationship studies in the early childhood education sector and lay the foundation for future studies. 131 articles that appeared in seven domestic academic journals related to early childhood education were selected and analyzed in order to better understand the general trends in the filed and the specific trends in terms of their content and methods. Our results indicate that the observation method was most common in the quantitative studies, and participant observation was most prevailent among qualitative studies. As for instrumentation, international instruments were most widely utilized, and the most dominant analysis method was descriptive statistics. In terms of reliability, internal consistency was checked most often, however, the majority of the studies failed to provide any information on validity and post-hoc analysis.

• Journal of Engineering Education Research
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• v.15 no.1
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• pp.9-17
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• 2012

Communication skills, such as writing documents and presenting technical details, are thought to be essential for modern engineers. Engineering students usually have less interest in writing and presentation than their humanities student counterparts and their concerns are different, too. So it is necessary to teach them in a different way which is suited to them. However, teaching such subjects has been a tricky problem for educators in terms of teaching methods. Also, to teach writing and presentation effectively for engineering students, collaboration between the faculties of different disciplines is necessary because each discipline has its own specific domain knowledge and approaches. But many unsolved problems exist with regard to how to deal with the technical and administrative aspects, and so on. This paper introduces one case in the education of technical writing and presentation, which is a collaboration between an engineering faculty and a faculty of literature. The literature faculty conducts basic education and training for writing skills, while the engineering faculty teaches the technical aspects of documentation, as well as presentation skills. The focus is placed on topics such as self-introduction, searching technical literature and materials, describing and explaining things and presentation practice, etc. During the class there is cooperation in each topic domain, while the faculties collaborate in teaching and evaluation.

• The Pure and Applied Mathematics
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• v.14 no.3
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• pp.139-151
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• 2007

We introduce the concept of intuitionistic fuzzy semiprimality of a semigroup which is an extension of semiprimality in it. And we obtain a characterization of a semigroup that is a semilattice of simple semigroups in terms of intuitionistic fuzzy semiprime interior ideals.