• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.5
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• pp.1755-1777
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• 2022

The development of wireless communication technology has led to the underutilization of radio spectra. To address this limitation, an intelligent cognitive radio network was developed. Specific emitter identification (SEI) is a key technology in this network. However, in realistic non-cooperative scenarios, the system may detect signal classes beyond those in the training database, and only a few labeled signal samples are available for network training, both of which deteriorate identification performance. To overcome these challenges, a meta-learning-based open-set identification system is proposed for SEI. First, the received signals were pre-processed using bi-spectral analysis and a Radon transform to obtain signal representation vectors, which were then fed into an open-set SEI network. This network consisted of a deep feature extractor and an intrinsic feature memorizer that can detect signals of unknown classes and classify signals of different known classes. The training loss functions and the procedures of the open-set SEI network were then designed for parameter optimization. Considering the few-shot problems of open-set SEI, meta-training loss functions and meta-training procedures that require only a few labeled signal samples were further developed for open-set SEI network training. The experimental results demonstrate that this approach outperforms other state-of-the-art SEI methods in open-set scenarios. In addition, excellent open-set SEI performance was achieved using at least 50 training signal samples, and effective operation in low signal-to-noise ratio (SNR) environments was demonstrated.

• English Language & Literature Teaching
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• v.12 no.3
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• pp.79-98
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• 2006

As one way of changing a teacher-fronted, grammar-based reading class into a meaningful, fun-creating one, this paper compared teacher- fronted reading with student-centered reading framed upon cooperative learning. In a study in which each type of reading method was conducted for college students in an EFL reading course for a period of one semester, data were gathered via questionnaires. The results showed that though each type of reading instruction came with its own strengths and weaknesses, student-centered reading instruction was preferred for various reasons. Most important, through an active participation in cooperative work, subjects were motivated and interested in L2 reading much, were exposed to various reading strategies and skills, and practiced them in a friendly, low-anxiety learning climate.

• Journal of the Korean earth science society
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• v.27 no.3
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• pp.279-288
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• 2006

We incorporated cooperative learning focusing on the 'Crustal Deformation' in five classes of second grade students, at an all-girls' middle school of Gimje city. The groups of cooperative learning were composed of four members of students each, according to the heterogeneous level. We conducted a pretest on the students' preference before incorporating the cooperative learning. After ten weeks of cooperative school work, the students took a post test with the same questions as the pretest. The result of this method greatly impacted the change on the students' scientific preference. It means that the students showed a positive change in their awareness of and participation in science classes, compared to before. However it is difficult to distinguish the differences in their scientific attitude on the recognition about scientists and habits which make them think scientifically. This resulted from the short period of ten weeks which is not sufficient to carry out the study strategy effectively. Surveys of the students on cooperative learning indicates that the middle level students prefer this method unlike the higher or lower level students. we are convinced that they can learn from the students of higher level and are able to help the lower level with the interaction through cooperative learning. According to the result of the survey, the method has some weaknesses; it arouses the high noise levels and consequent disturbance due to verbal interaction and of conflicts due to disagreements when they discuss the process. On the contrary, advantages are developing the students's interest in science class, helping them to learn, creating positive participation in class, and fostering mutual collaboration with other students through cooperative learning.

• Journal of the Korean Chemical Society
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• v.49 no.4
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• pp.417-425
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• 2005

• Journal of Korean Home Economics Education Association
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• v.12 no.3
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• pp.171-181
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• 2000

The purpose of this study is to compare and analyze on the result of learning accomplishment and attitude between two groups to certify the application possibility of the cooperative learning method in home economics education. This inquiry was investigated by two classes 95 students. of the first glade in high school a commercial girl’s high school located in Anyang city of Kyonggi province, and then classified in a cooperative learning group and a traditional learning group respectively, then the 6th lessons progressed, and the difference of results of the learning accomplishment and the learning attitude according to each group was analysed with the post tests of the learning accomplishment and the learning attitude of two groups. The results of this study are summarized as follows. (1) Three subordinate positions, which are knowledge, understanding and application field of learning accomplishment between the cooperative learning group and the traditional learning group. it highly and the traditional learning group it highly showed in comparison with the traditional learning group. (2) There are not any statistically significant difference in the attention- concentration field of learning attitude between the cooperative learning and the traditional learning groups, but the cooperative learning group in the learning method and the self learning field highly showed.

• Journal of Korean Elementary Science Education
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• v.25 no.2
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• pp.141-148
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• 2006

The purpose of this study is to examine the efforts of cooperative loaming through a student team-achievement division(STAD) model on elementary school students' learning achievements and science ,elated attitudes toward the field of astronomy. This study was conducted using 72 students of the fifth-grade class in a elementary school in Busan. The 18 science lessons of the 'Family of the sun' were executed over 6 weeks in the fifth-year students classes. In this study, the experimental group were exposed to cooperative learning through STAD and the contrast group were exposed to a traditional teacher-centered class. The results show that the STAD class of the experimental group had a greater effect upon the elementary school students' science learning achievement and science related attitudes toward the field of astronomy than those of the comparison group. Additionally, the students recognized that cooperative learning provokes both interest in loaming and in their studies generally and also they expressed a desire to continue with cooperative teaming methods.

• Journal of Korean Society of Forest Science
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• v.53 no.1
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• pp.56-61
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• 1981

Total 183 private forest owners in Chungnam-Do were surveyed in order to analyse the attitudes toward cooperative forest management and to find out the relationship of the attitudes with such socio-economic variables as owners' socio-economic status(SES), age and educational level. Major findings of the study are summarized as follows:- 1. Only 17.5 percent of the owners regards the cooperative management as a desirable alternative for the management of private forests. Significant difference of their attitudes is recognized only among the classes of the educational level. 2. About one-third of the owners wishes to participate to a cooperative, if established. The owners' intention of participating is positively related to the degree of S.E.S. and educational level, but negatively associated with that of age variable, and the differences among the classes of all variables are significant at the 0.01 or 0.05 levels. 3. More than half of the owners desires to have limited cooperatives, in which the members themselves manage their forest land with some management aspects being handled by the cooperative such as procurement of seedlings, protection measures, and marketing. The difference of responses among the classes of educational level is significant at the 0.01 level. 4. The owners, who agree with the idea of voluntary membership in the cooperative, are about 45 percent of the total. Significant difference is found only among the classes of the S.E.S. variable. 5. Nearly 60 percent of the owners wants to have self-help cooperative organizations. Significant difference of responses is recognized only among the classes of the age variable.

• Journal of the Korean earth science society
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• v.27 no.2
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• pp.121-129
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• 2006

The purpose of this study was to investigate the effects of the group reward and cooperative skill training on science achievement and learning motivation of elementary students. 3 classes of the 6th grade students were selected from an elementary school in Busan. Group I took traditional cooperative learning (TCL), group II took cooperative learning with competitive group reward (GR), and group III was trained in cooperative skill (CS) before cooperative learning. Students were taught about 'weather forecast' for thirteen periods and problem-based learning steps were applied in each class. The results from this study were as follows: First, there was an interactive effect between the treatment and achievement level in the science achievement test scores. In the case of high-level students the group reward was more effective than cooperative skill training on the science achievement; on the other hand, in the case of low-level students the cooperative skill training was more effective than the group reward on the science achievement. Second, there was no interactive effect between the treatment and achievement level in the motivation scores.

• Journal of the Korean Applied Science and Technology
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• v.40 no.1
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• pp.160-167
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• 2023

The purpose of this study was to find out the learning effect of applying problem-based learning in esthetic major education at universities and to provide basic data for developing teaching and learning methods that can strengthen competitiveness in esthetic education. Therefore, this study conducted an empirical educational effect analysis by applying PBL classes to 15 students taking oriental therapy, a esthetic major course opened at H University. As a result, the average value of learners' problem-solving ability and cooperative self-efficacy increased after participating in PBL classes, and the effectiveness of PBL teaching and learning methods was confirmed, suggesting effective teaching and learning methods to increase learners' problem-solving ability and cooperative self-efficacy in the field of esthetic.

• Journal of The Korean Association For Science Education
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• v.18 no.2
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• pp.201-208
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• 1998

Although cooperative learning strategies in many subject areas have been found to be effective, the effect of cooperative learning on academic achievement in science laboratory setting is not clear. Reported results on the effects of the strategies for higher achieving students are not also consistent. In this study, the cooperative learning strategies emphasizing student-centered learning which included higher order thinking activities were used in a elementary school science course. The cooperative and traditional learning groups were selected from fifth-grade classes, and taught about dissolution and solution for 16 class periods. The effects of the cooperative learning strategies upon students' academic achievement, science process skill, the attitude toward science instruction, and the perceptions of classroom environment were investigated. Two-way ANCOVA results revealed that the test scores of academic achievement and science process skill for the cooperative learning group were significantly higher than those of the traditional learning group. No interaction between the instruction and the level of previous achievement was found. The perceptions of confliction were higher in cooperative learning group. In the attitude toward science instruction and the perceptions of participation, however, no significant difference between the two groups was found. Educational implications are discussed.