• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.56-64
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• 2018

In recent years, imbalanced data is one of the most important and frequent issue for quality control in industrial field. As an example, defect rate has been drastically reduced thanks to highly developed technology and quality management, so that only few defective data can be obtained from production process. Therefore, quality classification should be performed under the condition that one class (defective dataset) is even smaller than the other class (good dataset). However, traditional multi-class classification methods are not appropriate to deal with such an imbalanced dataset, since they classify data from the difference between one class and the others that can hardly be found in imbalanced datasets. Thus, one-class classification that thoroughly learns patterns of target class is more suitable for imbalanced dataset since it only focuses on data in a target class. So far, several one-class classification methods such as one-class support vector machine, neural network and decision tree there have been suggested. One-class support vector machine and neural network can guarantee good classification rate, and decision tree can provide a set of rules that can be clearly interpreted. However, the classifiers obtained from the former two methods consist of complex mathematical functions and cannot be easily understood by users. In case of decision tree, the criterion for rule generation is ambiguous. Therefore, as an alternative, a new one-class classifier using hyper-rectangles was proposed, which performs precise classification compared to other methods and generates rules clearly understood by users as well. In this paper, we suggest an approach for improving the limitations of those previous one-class classification algorithms. Specifically, the suggested approach produces more improved one-class classifier using hyper-rectangles generated by using Gaussian function. The performance of the suggested algorithm is verified by a numerical experiment, which uses several datasets in UCI machine learning repository.

• Journal of Ship and Ocean Technology
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• v.9 no.2
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• pp.29-36
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• 2005

A hull form of Baltic ice class IA Aframax tanker has been developed taking into consideration of powering performance in brash ice channels based on IA class rules. Speed performance of the ship hull form in normal seagoing has been validated through model tests in a towing tank. The hull form design developed in this work has demonstrated good speed performance in normal seagoing although the ship design is entitled to ice class IA.

• Human Ecology Research
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• v.58 no.4
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• pp.561-583
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• 2020

This study developed and implemented a teaching · learning process plan for Home Economics in middle school by converging Habermas's three systems of action. It also examined the effect of the class through the evaluation of students and teachers who participated in the class. This study developed 10 sessions for a teaching and learning process plan by converging three systems of action and reconstructing learning elements related to 'balanced meal plan' and 'food choice' according to the practical action teaching model. After class, we surveyed the degree of help for students, analyzed the learning activity sheets, and analyzed the reflection journals of teachers to evaluate the effects of the class. This class was found to be the most helpful in practicing the healthy dietary life of students, expanding their thoughts, understanding learning contents, and helping them change their lives. As a result of analyzing the learning activity sheet, students gained enlightenment by reflecting and evaluating their action through the class; in addition, changes in interest, awareness, and action appeared. Through the convergence of three systems of action, teachers who practiced the class criticized and realized the act that students were unconsciously accepted. In addition, it confirmed the possibility that students could change their lives, family and society by promoting optimal nutrition and health for a good life that pursues the best good.

• Hwankyungkyoyuk
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• v.22 no.1
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• pp.1-11
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• 2009

Environmental Literacy is needed to establish a sustainable society and can be very well developed through Outdoor Environmental Education(OEE). However, establishing OEE in Korea is a very difficult. Thus, it is very important to find out which factors influence the sustainability of OEE. The purpose of this study is to identify those factors. Participatory observation research and some interviews were used in "The Whale Class" of the University of Georgia in the United States. Major findings and recommendations were as follows: (1) OEEs give participants good experiences about the environment; (2) Program operators of OEEs are enthusiastic about education and environmental conservation; (3) Good educational practices such as cooperative education and participation in conversation foster learning; (4) Good organizations with guest lectures from various environmental fields would be beneficial; (5) Public information about environmental programs would be helpful; (6) Administrative support for those organizations connected to environmental programs would be useful; and (7) OEE provide reflection activities to foster Environmental Literacy.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.66-72
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• 2023

Little attention appears to have been paid to the relevance of learning a good representation function in solving long tail tasks. Therefore, we propose a new loss function to ensure a good representation is learnt while learning to classify. We call this loss function Triplet Class-Wise Difficulty-Based (TriCDB-CE) Loss. It is a combination of the Triplet Loss and Class-wise Difficulty-Based Cross-Entropy (CDB-CE) Loss. We prove its effectiveness empirically by performing experiments on three benchmark datasets. We find improvement in accuracy after comparing with some baseline methods. For instance, in the CIFAR-10-LT, 7 percentage points (pp) increase relative to the CDB-CE Loss was recorded. There is more room for improvement on Places-LT.

• Journal of the Korean Chemical Society
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• v.66 no.3
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• pp.218-227
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• 2022

The purpose of this study is to analyze the opinions of students by using the text mining to the good points and improvements among the descriptive course evaluation written by the students who participated in the university chemistry laboratory class, and to derive the improvement for the class. We analyzed the frequency of occurrence, co-occurrence and network of key words. As a result of the study, in the network of good points in the class, the most frequent mentions were made between class and professor, along with explanation, understanding, student, passion, fun, TA, experiment, help, etc. In the network of improvements in the class, the most frequent mentions were made between class and student, along with professor, content, explanation, exam, wish, experiment, understanding, difficult, thought, problem, etc. In other words, the students suggested the opinion that the contents of the class were well understood and that they felt fun and satisfied with the experimental process due to 'easy and detailed explanation' and 'TA's assistance' as good points of the class. On the other hand, the students suggested the negative opinions that the understanding and concentration in the class was decreased due to 'difficulty of content and exam', 'excessive assignments', and 'class environment' as improvements of the class.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.269-279
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• 2018

The purpose of this research is to investigate how an elementary English class is presented in terms of communicative properties using COLT and TALOS because previous studies mainly used COLT. A lack of TALOS has shown on the previous studies. Also, this study takes a close look into whether the English class is communicative or not communicative since previous studies criticized in that elementary English classes are not communicative. For the purposes of this research, COLT part B and TALOS low-inference were used to analyze one elementary English class which had won the grand prize at English class contest. The result of this study revealed that the class is communicative in terms of high quantity and quality of students utterances, high ratio of students' discourse initiation, students' unpredictable information giving utterances and extension of utterances. Findings from this study revealed the good elementary English class characteristics of this class: students' participation, focus on affective atmosphere, students-directed activities, and unconscious internalization of target expressions through repetition.

• Journal of Creative Information Culture
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• v.6 no.3
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• pp.169-177
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• 2020

In this study, the satisfaction level of the class between 'Content utilization and task performance class' and 'real-time interactive class' was compared and analyzed among the types of online classes conducted in elementary schools. The researchers conducted a study to compare and analyze the satisfaction level of classes in 'Content utilization and task performance class' and 'Real-time interactive class', and the research group selected 98 elementary school students in Hwaseong. As a result of the analysis, the satisfaction level of classes for "real-time interactive classes" was high. The satisfaction level of students' characteristics was analyzed, students who were not good at performing their task and those who were not good at concentrating on their classes were more satisfied with 'content utilization and task performance classes.'

• Journal of Engineering Education Research
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• v.13 no.6
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• pp.72-79
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• 2010

The purpose of this study was to explore good college instructional practice in the industrial teacher education in order to improve the quality of instruction. The study that what is the good instructional practice have been relatively more researched on elementary and middle school than colleges. Research methods used in this study were an individual interview and focus group interview. Research results and analyses were three directions in good instructional practice to be in teacher's college, engineering college and teacher's graduate school. Based on the result of the study, some recommendations for future researches were made as follows: First, good instructional practice in teacher's college were to be interested in students and be enthusiastic class and practical training. Second, good instructional practice in engineering colleges were class to be a faithful college program for teaching profession orientation and practical training. Third, good instructional practice in teacher's graduate school were class to allow for an academic standard and subjects of special study of each students.

• Journal of Korean Elementary Science Education
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• v.29 no.4
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• pp.451-464
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• 2010

This study examined the perception of teachers and students on the practice of elementary science class. For this study, an examination tool was made by extracting characteristics of good science class through precedent study investigation and revising it in a questionnaire form of a Likert scale, and conducted to 194 elementary teachers and 320 elementary students. As a result of the study, teachers generally perceived science class positively and teachers with career more than 6 years thought it more positively than them with career less than 5 years. Consequently students have a substantially positive perception level about the practice of the elementary science class, and students of 3th and 4th grade perceived science class positively than 5th and 6th grade in all domains. Finally when analyzing perception difference between teachers and students about the practice of the elementary science class, it appeared that students perceived science class more positively than teachers in most questions.