• Journal of the Korean School Mathematics Society
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• v.23 no.1
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• pp.129-158
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• 2020

In this study, we presented two geometric tasks to three 11th grade students to identify the characteristics of the images that the students had at the beginning of problem-solving in the problem situations and investigated how their images changed during problem-solving and effected their problem-solving behaviors. In the first task, student A had a static image (type 1) at the beginning of his problem-solving process, but later developed into a dynamic image of type 3 and recognized the invariant relationship between the quantities in the problem situation. Student B and student C were observed as type 3 students throughout their problem-solving process. No differences were found in student B's and student C's images of the problem context in the first task, but apparent differences appeared in the second task. In the second task, both student B and student C demonstrated a dynamic image of the problem context. However, student B did not recognize the invariant relationship between the related quantities. In contrast, student C constructed a robust quantitative structure, which seemed to support him to perceive the invariant relationship. The results of this study also show that the success of solving the task 1 was determined by whether the students had reached the level of theoretical generalization with a dynamic image of the related quantities in the problem situation. In the case of task 2, the level of covariational reasoning with the two varying quantities in the problem situation was brought forth differences between the two students.

• Journal of Elementary Mathematics Education in Korea
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• v.20 no.4
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• pp.601-625
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• 2016

In this study, I hoped to reveal the understanding of pre-service elementary teachers about proportional reasoning and the traits of proportional reasoning strategy used by pre-service elementary teachers. The results of this study are as follows. Pre-service elementary teachers should deal with various proportional reasoning tasks and make a conscious effort to analyze proportional reasoning task and investigate various proportional reasoning strategies through teacher education program. It is necessary that pre-service elementary teachers supplement the lacking tasks such as qualitative reasoning and distinction between proportional situation and non-proportional situation. Finally, It is suggested to preform the future research on teachers' errors and mis-conceptions of proportional reasoning.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.1
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• pp.63-69
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• 1999

To offer a general guideline for the quantitative analysis of airborne pollutants, we designed and conducted a comprehensive QA/QC test using two different strategic approaches, namely (1) field-based comparative measurement and (2) laboratory-based comparative analysis. The former task was performed to make meaningful comparison of combined errors occurring from both sampling and analytical techniques in the measurements of such components as: (1) criteria pollutants, (2) volatile organic compounds (VOCs), and (3) particulate matters with the associated metals and ions. The latter task was also conducted to compare various types of bias arising mainly from the laboratory analytical procedures of (1) gaseous standards of VOCs and (2) of aqueous standards of metals and ions. The concentration data derived from each of these two different types of major tasks were evaluated per chemical species categorized as above. While the very details of these studies are to be reported on an individual basis according to the above classification of the project, this paper is presented to provide an overview of the whole project - its aim and direction.

• English Language & Literature Teaching
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• v.15 no.3
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• pp.223-248
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• 2009

Previous research on the impact of pretask planning on subsequent second language (L2) production has mainly focused on the linguistic quality of planned production, while learners' thought processes and perceptions about planning have been relatively less explored. In addition, few previous planning studies have examined whether the learners did in fact follow the pretask instructions, thus leaving the role of pretask instructions in the planning process unexplored. Therefore, the present study investigated whether pretask instructions affect attentional allocation as well as what cognitive operations planners engage in and what their perceptions about planning are. Forty-three Korean EFL classroom learners were divided into two groups: before having time to plan for an oral story retelling task, one group received general instructions, while the other group received specific instructions. The findings, based on both quantitative and qualitative data analysis, indicated no large effects of pretask instructions on the planners' attentional focus. Rather, the qualitative analysis identified a number of other factors that influenced learners' decision making as well as their general processes and approaches to planning and their perceptions about planning and thinking aloud while planning. Implications for L2 teaching as well as limitations of the study are discussed.

• Proceedings of the KSPS conference
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• 2007.05a
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• pp.78-83
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• 2007

The purpose of present study was to investigate the characteristics of disfluency between the Korean-English bilingual and Korean monolingual children, matched by their chronological age with the bilingual children. Twenty-eight children, 14 bilingual children and 14 monolingual children participated in this study. The experimental tasks consisted of the play situation and the task situation. The conclusion is (a) The score of total disfluency of the bilingual was significantly higher than that of the monolingual. The score of normal disfluency of the bilingual was significantly higher than that of the monolingual. The most frequent type is Interjection in both groups. All shows higher score in the task situation than the play situation. The bilingual children have quantitative and qualitative differences in disfluency score and types from the monolingual. (b) The bilingual were divided into two groups such as 6 Korean-dominant bilingual and 8 English-dominant bilingual. All shows more disfluency in their non-dominant language. The most frequent type is Interjection in both groups. (c) The higher the chronological age and the expressive language test score is, the lower the disfluency score is. The earlier the exposure age to the 2nd language is, the higher the disfluency score is. There is no correlation between resident month at foreign country and the disfluency.

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.4
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• pp.263-270
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• 2004

Recently, wavelet transform have been applied to various kinds of problems in many fields. In this paper, we propose method of Daubechies wavelet to detect several kinds of important characteristic waves in tasks EEG that are needed to diagnose EEG. We show that our system could be attained higher performance in detecting characteristic waves than the other methods. In this system, the architecture of the neural network is a three layered feed-forward networks with one hidden layer which implements the error back propagation teaming algorithm. Applying the algorithms to 4 subjects show 92% classification rates. The proposed system shows a little more accurate diagnosis for task EEG by Wavelet and neural network. From the simulation results by the implemented system, we demonstrated this research can be reduce doctor's labors and quantitative diagnosis of task EEG.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.3
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• pp.2140-2146
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• 2020

Background: Stroke patients exhibit arm global synkinesis (GS), involuntary movement due to muscle weakness and irregular muscle tension. But currently there are few studies examined the effects of GS on activates of daily living in stroke patients. Objectives: To investigate the effects the effects of task-oriented bilateral movements, which promote brain plasticity and are based on neurological theory, using the unaffected arm and the affected arm. Design: Quasi-randomized trial. Methods: Twenty stroke patients were randomly assigned to experimental group I (n=10) and experimental group II (n=10). Before the intervention, arm GS was measured using surface electromyography, and the Motor Activity Log evaluated the quantitative and qualitative uses of the affected arm in daily life. The same items were measured four weeks later. Results: The changes in the GS of the arm of experimental group I showed statistically significant differences only in bending motions (P<.05). Both groups showed statistically significant differences in the amount of use (AOU) and the quality of movement (QOM) scores (P<.01). Comparing the groups, statistically significant differences in GS appeared during bending motions (P<.05), and in the AOU (P<.01) and the QOM scores (P<.05). Conclusion: The intervention in GS reduced the abnormal muscle tension of the affected side by increasing the use of the ipsilateral motor pathway, indicating its effectiveness in improving upper limb functions with smooth contraction and relaxation of the muscles.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.1025-1032
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• 2021

The study investigates factors affecting the loyalty of Food Delivery Application (FDA) service in Thailand. This study employs quantitative research methodology with a non-probability sampling method to draw 510 FDA samples from the FDA users in Thailand. The online questionnaires with a Cronbach's alpha coefficient of 0.886 were used as a research tool to collect data from samples. By using the Structural Equation Modeling (SEM) to analyze data, the results show that trustworthiness, social influence, system design, and task-technology fit affect the user's technology acceptance, which also show the significant relationship with the loyalty of FDA users in Thailand. The study checks the harmony with the statistics; χ2 = 258.686, df. =160, χ2/df. = 1.616, p-value = 0.050, CMIN/DF = 1.616, GFI = 0.960, AGFI = 0.969, TLI = 0.953, CFI = 0.965, RMSEA = 0.047, significant level at 0.05, along with testing the weight factor. In conclusion, the research model was harmonious with the empirical data at the significant level 0.05. The finding of this study suggested that the FDA service provider might apply this research finding to develop a greater understanding of the FDA's customer loyalty, as well as determine marketing strategies, identify opportunities, and create a competitive advantage in the future.

• Smart Structures and Systems
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• v.29 no.6
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• pp.777-783
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• 2022

Even though several deep learning-based methods have been applied in the field of acoustic source localization, the previous works have only been conducted using the two-dimensional representation of the beamforming maps, particularly with the planar array system. While the acoustic sources are more required to be localized in a spherical microphone array system considering that we live and hear in the 3D world, the conventional 2D equirectangular map of the spherical beamforming map is highly vulnerable to the distortion that occurs when the 3D map is projected to the 2D space. In this study, a 3D deep learning approach is proposed to fulfill accurate source localization via distortion-free 3D representation. A target function is first proposed to obtain 3D source distribution maps that can represent multiple sources' positional and strength information. While the proposed target map expands the source localization task into a point-wise prediction task, a PointNet-based deep neural network is developed to precisely estimate the multiple sources' positions and strength information. While the proposed model's localization performance is evaluated, it is shown that the proposed method can achieve improved localization results from both quantitative and qualitative perspectives.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.3
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• pp.535-546
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• 2024

This research aims to develop a model to objectively and quantitatively measure the skill level of aircraft body assembly workers. Because aircraft body assembly is predominantly a manual process, skills management is a key factor of manufacturing competitiveness. Currently, skills management relies on the subjective judgment of supervisors, which lacks objectivity and reliability. As a remedy, this study proposed a systematic skill management model based on objective and quantitative evaluation criteria. By considering prior research, we developed an evaluation model that takes into account both expertise and versatility of a worker. The model selected five major tasks required for aircraft body assembly and established evaluation criteria considering the difficulty and maturity of each task. We then conducted a pilot evaluation with over 200 workers in four SMEs to validate the practicality and effectiveness of the model. Consequently, we identified and addressed the limitations of the existing evaluation method, subdivided the skill levels based on the performance capabilities of each task, and proposed a career growth path. The developed evaluation model offers critical data for executives and managers to determine work assignments, education, training, performance incentives, and wages. It is expected to enhance the attraction of new talent and systematize skills management in aviation manufacturing in the future.