• Journal of Korean Elementary Science Education
• /
• v.31 no.3
• /
• pp.298-310
• /
• 2012

The purpose of this study was to analyze the characteristics of elementary school students' prediction changes by the suggestion types in a multiple anomalous situation. We investigated the responses, the rate and time of changing prediction, and cognitive conflicts of the students when repeated anomalous situation was suggested in experimental or logical way in science classes focused on buoyancy. As the anomalous situation was repeated, the students to change the prediction increased in number and also the rates to choose the correct prediction became higher. The group who was exposed in experimental way changed their prediction more than in logical way. In addition, when we classified the students to change the prediction by types, the group in experimental way showed higher rate of NM, MM type and FFT type. With anomalous situation repeated, cognitive conflicts of the students has been gradually declining in both groups. But it seemed that the group in experimental way experienced higher mental conflicts. In particular, as students changed the prediction more and arrived at the correct answer after changing their prediction, all the more so. It is concluded that the degree of students' changing prediction and experiencing cognitive conflict can be different according to the suggestion types for situation. Therefore the correlation with cognitive conflict factors can be also observed with the types of students' reactions.

• Journal of The Korean Association For Science Education
• /
• v.19 no.4
• /
• pp.635-644
• /
• 1999

The effect of cooperative learning in a heuristic approach (four stage-problem solving strategy) that also emphasized molecular level representation was studied. Three high school classes (N=130) were randomly assigned to St group (using strategy individually), St-Co group (using strategy in cooperative group), and control group. After instruction, students' multiple-choice problem solving ability, strategy performing ability, and the perception of involvement were compared. Students' preferred instruction type was also examined. Although multiple-choice problem solving ability were not different significantly, a significant interaction between the treatment and the previous achievement level was found in strategy performing ability. Analysis of simple effects indicated that the medium-level students in the St group performed better than those in the St-Co group. In the perception questionnaire of involvement. however, the scores of the St group were significantly lower than those of the control group. The instruction type that students most preferred was also St-Co.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.12
• /
• pp.1208-1218
• /
• 2012

Disseminating broadcast information stably and reliably in IEEE 802.11-like CSMA wireless networks requires that a source should seek collision-free transmission to multiple receivers and keep track of the reception state of the multiple receivers. We propose a simple yet efficient feedback scheme for stable reliable broadcast in wireless networks, called 2-polling feedback, where the state of two receivers are checked by a source before its broadcast transmission attempt We present a performance analysis of the class of reliable broadcast feedback schemes in terms of two performance metrics (packet transmission delay and packet stable time). The analysis results show that the proposed 2-polling feedback scheme outperforms the current existing classes of feedback schemes in the literature, i.e., all-polling feedback and 1-polling feedback. The 2-polling feedback scheme has lower asymptotic complexity than the all-polling feedback, and has the same asymptotic complexity as the 1-polling feedback but exhibits almost 50 % reduction in packet stable time.

• Journal of The Korean Association For Science Education
• /
• v.20 no.4
• /
• pp.519-526
• /
• 2000

In this study, the effects of visual organization and cooperative learning in problem-solving strategy were investigated. Three classes (N=127) at a high school were assigned to SV (Strategy-Visual organization) group, SVC (Strategy-Visual organization-Cooperative learning) group, and control group. After instructions, students' multiple-choice problem-solving ability, strategy performing ability, anxiety about chemistry learning, perception of involvement, and motivation to learning science were examined. Although multiple-choice problem-solving ability was not different significantly, there was a significant main effect in strategy performing ability. The scores of the SV and SVC groups were significantly higher than those of the control group, especially in the subcategories of problem understanding and recalling related principles. In the tests of perception of involvement and motivation to learning science, the scores of the SV and SVC groups were also significantly higher than those of the control group. However, problem-solving strategy using visual organization could not alleviate anxiety about chemistry learning.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.8B
• /
• pp.1371-1382
• /
• 2000

IMT-2000 system is the third generation mobile communication system which aims at mobile multimedia services with global roaming. Like 2nd generation system, the IMT-2000 system is also under strong influence of interferences among active subscribers in the multiple access environment. That is, in multiple access environment, signals from one subscriber could interfere with others in the same cell or in the neighboring cells. The interference control in the IMT-2000 systems is much more difficult then the interference control in the 2ndgeneration CDMA cellular systems, since the transmitted power of a subcriber might be different that of others in the IMT-2000 system. In this paper, a parallel interference cancellation with traffic discrimination is proposed which can effectively cancel interferences by grouping the subscribers into several equi-power classes. As a conclusion, simulation results show that the proposed method outperforms the conventional partial PIC scheme in several aspects.

• Korean Journal of Remote Sensing
• /
• v.20 no.6
• /
• pp.419-425
• /
• 2004

This study has proposed a data fusion method based on the Dempster-Shafer evidence theory The Dempster-Shafer fusion uses mass functions obtained under the assumption of class-independent Gaussian assumption. In the Dempster-Shafer approach, uncertainty is represented by 'belief interval' equal to the difference between the values of 'belief' function and 'plausibility' function which measure imprecision and uncertainty By utilizing the Dempster-Shafer scheme to fuse the data from multiple sensors, the results of classification can be improved. It can make the users consider the regions with mixed classes in a training process. In most practices, it is hard to find the regions with a pure class. In this study, the proposed method has applied to the KOMPSAT-EOC panchromatic image and LANDSAT ETM+ NDVI data acquired over Yongin/Nuengpyung. area of Kyunggi-do. The results show that it has potential of effective data fusion for multiple sensor imagery.

• Journal of the Korean Society of School Health
• /
• v.24 no.1
• /
• pp.61-70
• /
• 2011

Purpose: To identify factors associated with children's discriminatory attitudes towards fully recovered children who contracted the 2009 Influenza A (H1N1), in order to provide fundamental information to improve health education for children. Methods: Cross-sectional data were collected from the entire 6th grade classes (N=2,323) of 11 elementary schools randomly selected from 11 school districts in the Seoul Metropolitan Area of South Korea. Questionnaires were used to assess participants' knowledge of and attitudes towards the Influenza A (H1N1) virus. Results: Multiple regression analyses were used to investigate the factors associated with children's discriminatory attitudes toward fully recovered children who had contracted the 2009 Influenza A (H1N1). Multiple regression analysis revealed that perceived risk of contracting and knowledge of 2009 influenza A (H1N1) were significant factors in predicting a child's attitude toward fully recovered Influenza A (H1N1) patients, after controlling for socioeconomic variables. Conclusion: The findings suggests that perceived risk and knowledge play important roles in formulating children's appropriate attitudes towards Novel influenza A (H1N1) patients who are fully recovered from the disease. To promote and maximize children's attitudes in this area, health education needs to be directed at children to reduce excessive concern about contracting the virus and to improve their overall health knowledge.

• Journal of The Korean Association of Information Education
• /
• v.24 no.6
• /
• pp.539-550
• /
• 2020

This study establishes the scientific basis for the use of digital learning materials through the education-neurological research method and derives implications for education based on education-neurological understandings. The main findings of the education-neurological analysis of digital learning materials are as follows: First, various sensory stimuli go through multiple sensory neurons and deep sections of the upper sphere and make possible the cooperative processing of information. Second, indirect experience from digital learning materials helps students understand the learning contents vividly through the mirror neuron system. Third, positive emotions originating from digital learning materials promote functions of dopamine, the reticular activating system, frontal-striatal circuit, cerebrum cortex. Based on the findings, the study suggests the following educational implications. First of all, when selecting digital learning materials, teachers should consider expression forms, learning contents, the flow of classes, and the adverse effects of digital learning materials. Next, it is effective to utilize digital learning materials in the lecture for provoking curiosity and enjoyment, maintaining interest and effort, and reviewing what students learned.

• The Plant Pathology Journal
• /
• v.37 no.2
• /
• pp.99-114
• /
• 2021

Tan spot of wheat, caused by Pyrenophora tritici-repentis (Ptr), results in a yield loss through chlorosis and necrosis of healthy leaf tissue. The major objective of this study was to compare gene expression in resistant and susceptible wheat cultivars after infection with Ptr ToxA-producing race 2 and direct infiltration with Ptr ToxA proteins. Greenhouse experiments included exposure of the wheat cultivars to pathogen inoculum or direct infiltration of leaf tissue with Ptr-ToxA protein isolate. Samples from the experiments were subjected to RNA sequencing. Results showed that ToxA RNA sequences were first detected in samples collected eight hours after treatments indicating that upon Ptr contact with wheat tissue, Ptr started expressing ToxA. The resistant wheat cultivar, in response to Ptr inoculum, expressed genes associated with plant resistance responses that were not expressed in the susceptible cultivar; genes of interest included five chitinases, eight transporters, five pathogen-detecting receptors, and multiple classes of signaling factors. Resistant and susceptible wheat cultivars therefore differed in their response in the expression of genes that encode chitinases, transporters, wall-associated kinases, permeases, and wound-induced proteins, among others. Plants exposed to Ptr inoculum expressed transcription factors, kinases, receptors, and peroxidases, which are not expressed as highly in the control samples or samples infiltrated with ToxA. Several of the differentially expressed genes between cultivars were found in the Ptr resistance QTLs on chromosomes 1A, 2D, 3B, and 5A. Future studies should elucidate the specific roles these genes play in the wheat response to Ptr.

• The Journal of the Korea Contents Association
• /
• v.22 no.10
• /
• pp.392-403
• /
• 2022

The purpose of this study is to investigate the effect of interpersonal relationships and communication skills of nursing students who received blended learning classes on adjustment to college Life. The subjects of this study were 133 first and second year nursing students. The survey was conducted from november 22th to december 3th. 2021. The data was analyzed with the SPSS/WIN 26.0 program. Descriptive statistics and meen differences were analyzed using an t-test, ANOVA, Pearson's correlation coefficient, Multiple regression. The result adjustment to college life of interpersonal relationship, communication competence it was found that there was a significant positive correlation between. The factors of communication competence, interpersonal relationship, Nursing and admissions motivation were impact on the adjustment to college life level of nursing students. The explanatory power of this was 44.3%. In conclusion, a strategy for improving communication skills and smooth interpersonal relationships is needed so that nursing students who have received blended learning can adjustment to college life.