• Journal of the Korean GEO-environmental Society
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• v.25 no.4
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• pp.13-20
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• 2024

In this paper, a parallel analysis algorithm for Smoothed Particle Hydrodynamics (SPH), one of the numerical methods for fluidic materials, is introduced. SPH, which is a meshless method, can represent the behavior of a continuum using a particle-based approach, but it demands substantial computational resources. Therefore, parallel analysis algorithms are essential for SPH simulations. The domain decomposition algorithm, which divides the computational domain into partitions to be independently analyzed, is the most representative method among parallel analysis algorithms. In Discrete Element Method (DEM) and Molecular Dynamics (MD), the Cartesian coordinate-based domain decomposition method is popularly used because it offers advantages in quickly and conveniently accessing particle positions. However, in SPH, it is important to share particle information among partitioned domains because SPH particles are defined based on information from nearby particles within the smoothing length. Additionally, maintaining CPU load balance is crucial. In this study, a highly parallel efficient algorithm is proposed to dynamically minimize the size of orthogonal domain partitions to prevent excess CPU utilization. The efficiency of the proposed method was validated through numerical analysis models. The parallel efficiency of the proposed method is evaluated for up to 30 CPUs for fluidic models, achieving 90% parallel efficiency for up to 28 physical cores.

• Journal of Korean Elementary Science Education
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• v.43 no.2
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• pp.219-232
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• 2024

This study aims to determine the perspectives of pre-service elementary school teachers on the science curriculum in the fourth industrial revolution era. In this study, 128 pre-service elementary school teachers were asked to express their perspectives on the Saber-toothed Tiger Curriculum through photovoice activities. The resulting images were classified into three types: conservative, progressive, and radical perspectives. The number of both conservative and progressive perspectives was similar and high, whereas the number of radical perspectives was l ow. Those who had conservative perspectives on the Saber-toothed Tiger curriculum regarded "Inquiry" as the basis of the science curriculum, which should be maintained regardless of the time period and environment. Similarly, older teachers believed that this curriculum was based on eternal truth, which should be protected. Those who showed progressive perspectives on the Saber-toothed Tiger curriculum regarded a progressive person as someone succeeding to the blood of "New fist," and they showed positive attitudes toward AI-based education such as coding and meta-verse, regarding these practices as part of the teaching and learning method that could replace the existing inquiry-based education. Those who showed radical perspectives on the Saber-toothed Tiger Curriculum assumed critical attitudes toward the rapidly changing political circumstances of science education and criticized conflicts between different social classes formed through progressive curriculum. Based on these results, this study found that pre-service elementary school teachers needed to consider the science curriculum from several different perspectives rather than just one.

• Journal of The Korean Association For Science Education
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• v.44 no.2
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• pp.195-207
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• 2024

The purpose of this study was to explore high school science teachers' perceptions and practices regarding the implementation of achievement standards-based assessment (ASA) in their science teaching. To achieve this, semi-structured individual interviews were conducted with 20 science teachers who had implemented ASA. The participating teachers were asked to share their opinions on ASA implementation, the effects of ASA on changes in their teaching, and students' reactions to ASA. The results were as follows. Most of the teachers recognized that the initial intention behind ASA implementation began to be realized in schools only after course rankings were no longer required to be indicated. Some teachers felt that ASA allowed them to focus on students' progress, rather than evaluating them by achievement scores. It also helped some teachers identify students who were experiencing learning difficulties and offer appropriate support. In addition, some teachers acknowledged being able to reorganize their science lessons according to the essential goals of science subjects in the curriculum and provide more detailed feedback on students' achievements. However, some teachers expressed difficulties in setting an appropriate level of achievement for their lessons or in evaluating students' progress using qualitative methods. Lastly, the teachers expressed concerns about the remarkably lower motivation of some students for learning science after the indication of course ranking was no longer required.

• Journal of The Korean Association For Science Education
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• v.44 no.2
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• pp.219-229
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• 2024

The purpose of this study is to analyze the concerns and difficulties encountered by authors involved in the development of integrated science textbooks. Specifically, it focuses on their experiences with understanding and implementing the 2022 revised science curriculum. We collected 89 opinions from textbook authors and categorized them into several key areas: understanding the terminology and descriptors provided in the curriculum, structuring learning content, inquiries and activities, and the depth and scope of learning content. The analysis revealed that the most difficulty encountered by the textbook authors was in defining the level and scope of learning content. Many also expressed concerns and difficulties related to the ambiguity of terms and predicates. In terms of the composition of learning content, difficulties were identified in concerning the repetitive descriptions of achievement standards and the discrepancy between the arrangement of achievement standards and the flow of learning. Regarding inquiries and activities, there were experiments presented that were difficult to experience or actually implement, along with limitations in activity composition due to the need to optimize learning volume. Given the importance of high-quality textbooks for effective science education at the national level, it is crucial to establish effective communication channels between curriculum developers and textbook authors. Additionally, a robust support system for textbook development should be established.

• The Transactions of the Korea Information Processing Society
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• v.13 no.3
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• pp.148-155
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• 2024

Despite the increasing importance of irony and sarcasm detection in the field of natural language processing, research on the Korean language is relatively scarce compared to other languages. This study aims to experiment with various models for irony detection in Korean text. The study conducted irony detection experiments using KoBERT, a BERT-based model, and ChatGPT. For KoBERT, two methods of additional training on sentiment data were applied (Transfer Learning and MultiTask Learning). Additionally, for ChatGPT, the Few-Shot Learning technique was applied by increasing the number of example sentences entered as prompts. The results of the experiments showed that the Transfer Learning and MultiTask Learning models, which were trained with additional sentiment data, outperformed the baseline model without additional sentiment data. On the other hand, ChatGPT exhibited significantly lower performance compared to KoBERT, and increasing the number of example sentences did not lead to a noticeable improvement in performance. In conclusion, this study suggests that a model based on KoBERT is more suitable for irony detection than ChatGPT, and it highlights the potential contribution of additional training on sentiment data to improve irony detection performance.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.13-17
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• 2024

A color sensor is an optical sensor used to take pictures of objects, including the human body, and reproduce them on a monitor. A color sensor quantifies the red, green, and blue light coming from an object and expresses it as a digital number, and can judge the state of the object by comparing the values ​​or the ratio.In this study, the standard colors displayed on the monitor were measured using a color sensor, and the magnitudes of the red, green, and blue components, or RGB values, were compared with the values ​​indicated by the computer. When measured with the TCS 34725 color sensor, even when the light generated by the computer consists of only one or two of red, green, and blue light, the color sensor detected all three components. Additionally, when the colors of two monitors with the same RGB values ​​were measured using a color sensor, different RGB values ​​were measured. These results can be attributed to the imperfection of the color filters used to express colors on the monitor and the imperfect optical characteristics of the photodiodes used in the color sensor. When photographing an object and judging its condition based on its color, you must use the same type of camera or smartphone.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.891-899
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• 2024

The Fourth Industrial Revolution is centered on a personalized demand fulfillment economy and is all about transformation and flexible processing that can deliver what customers want in real time across space and time. This paper implements the construction and operation of a packaging platform that can instantly procure the required packaging products based on real-time orders and evaluates its performance. The components of customer satisfaction are flexible and dependent on the situation which requires efficient management of enterprise operational processes based on an e-SCM platform. An OMS optimized for these conditions plays an important role in maximizing and differentiating the efficiency of a company's operations and improving its cost advantage. OMS is a system of mass customization that provides efficient MOT(Moment of Truth) logistics services to meet the eco-friendly issues of many individual customers and achieve optimized logistics operation goals to enhance repurchase intentions and sustainable business. OMS precisely analyzes the collected data to support information and decision-making related to efficiency, productivity, cost and provide accurate reports. It uses data visualization tools to express data visually and suggests directions for improvement of the operational process through statistics and prediction analysis.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1110-1122
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• 2023

Purpose This study aimed to assess the variability of transrectal shear wave elastography (SWE) using a designed phantom. Materials and Methods In a phantom, the SWE values were examined by two radiologists using agarose and emulsion silicone of different sizes (1, 2, and 3 cm) and shapes (round, cubic) at three depths (1, 2, and 3 cm), two region of interest (ROI) and locations (central, peripheral) using two ultrasound machines (A, B from different vendors). Variability was evaluated using the coefficient of variation (CV). Results The CVs decreased with increasing phantom size. Significant changes in SWE values included; agarose phantom at 3 cm depth (p < 0.001; machine A), 1 cm depth (p = 0.01; machine B), emulsion silicone at 2 cm depth (p = 0.047, p = 0.020; both machines). The CVs increased with increasing depth. Significant changes in SWE values included; 1 cm agarose (p = 0.037, p = 0.021; both machines) and 2 cm agarose phantom (p = 0.047; machine A). Significant differences in SWE values were observed between the shapes for emulsion silicone phantom (p = 0.032; machines A) and between ROI locations on machine B (p ≤ 0.001). The SWE values differed significantly between the two machines (p < 0.05). The intra-/inter-operator agreements were excellent (intraclass correlation coefficient > 0.9). Conclusion The phantom size, depth, and different machines affected the variability of transrectal SWE.

• The Journal of the Acoustical Society of Korea
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• v.43 no.3
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• pp.361-367
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• 2024

Ultrasound in the air is widely used in industry as a measurement technique to prevent abnormalities in the machinery. Recently, the use of airborne ultrasound imaging techniques, which can find the location of abnormalities using an array transducers, is increasing. A beamforming method that uses the phase difference for each sensor is used to visualize the location of the ultrasonic sound source. We exploit a random sparse ultrasonic array and obtain beamforming power distribution on the source in a certain distance away from the array. Conventional beamforming methods inevitably have limited spatial resolution depending on the number of sensors used and the aperture size. A high-resolution ultrasound imaging technique was implemented by applying functional beamforming as a method to overcome the geometric constraints of the array. The functional beamforming method can be expressed as a generalized beam forming method mathematically, and has the advantage of being able to obtain high-resolution imaging by reducing main-lobe width and side lobes. As a result of observation through computer simulation, it was verified that the resolution of the ultrasonic source in the air was successfully increased by functional beamforming using the ultrasonic sparse array.

• Communications of Mathematical Education
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• v.38 no.2
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• pp.121-144
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• 2024

This study analyzes how the academic achievement of students in Korea changes as they transition from 4th grade of elementary school to 2nd grade of middle school, considering that the 4th graders in the previous TIMSS cycle become 2nd graders in the next cycle. In particular, this study selects and compares the eight main countries in the TIMSS math evaluation (Korea, Singapore, Taiwan, Japan, USA, UK, Australia, and Russia) to analyze the trend of change in academic achievement of Korean students according to school grade transition. The trend of change in academic achievement of students was analyzed not only overall but also by content area (number, geometry and measurement, data representation (data and probability/data and probability), gender, and regional scale. The analysis focused on the average score and the proportion of students by achievement level. The results of the study are as follows. First, there was no significant change in the average score of Korean students' academic achievement as the school grade transitioned, but the achievement gap widened in terms of the proportion by achievement level. Second, there were differences in students' academic achievement by content area according to school grade transition, and the pattern differed depending on the evaluation cycle. Third, there was a significant gap in students' math academic achievement depending on gender and regional scale of school location. This study reveals that the achievement gap among students in our country widens as they transition between school levels. The gap is found to vary in terms of achievement level, math content area, student gender, and school location. To alleviate these disparities, more substantial research and support are proposed in addition to policy implementation by the government or provincial offices of education.