• Clean Technology
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• v.30 no.3
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• pp.159-174
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• 2024

The rapid increase in energy consumption based on fossil fuels is accelerating global warming. In particular, the road transportation sector has high carbon dioxide emissions, so transitioning towards electric vehicles is recommended. Thus, the importance of secondary batteries is increasing. Secondary batteries are reversible batteries that use energy and can be reused through a charging and discharging process. Currently, lithium-ion batteries are widely used. Secondary batteries place importance on six major factors: energy, output, lifespan, environmental friendliness, cost, and stability. Research is actively being conducted to satisfy all six factors by understanding the material characteristics of each component of the battery. As it is difficult to move away from lithium as a cathode material, researchers are investigating higher performance materials that mix materials such as cobalt, nickel, manganese, and aluminum with lithium and use graphite, silicon, and lithium metal to increase capacity. In the case of electrolytes, liquid electrolytes are still mainly used. However, solid electrolytes are being studied due to their stability, but additional research must be conducted to satisfy the energy and output factors. This review paper aims to provide an understanding of secondary batteries through an overview of secondary batteries, the materials and characteristics of their components, their technological trends, and their associated companies.

• Journal of the Korean earth science society
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• v.27 no.1
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• pp.15-19
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• 2006

In this study, the meteorology terms in the geography text books of North Korea which includes all of the meteorology educational contents in secondary school curriculum are compared with those in the earth science text books in South Korea. Forty science terms which are the same meaning but composed of different words are picked up to investigate the degree for 89 high school students in Chonnam province to perceive the meanings correctly. High school students' perceptions is on the average 30% higher in terminology of South Korea textbooks than in those of North Korea. But, students' perceptions on 9 North Korean terms is rather higher compared to South Korean terms. Twenty six (83.9%) terms which are difficult for high school students to perceive correct meanings are those lately composed of North Korean native words. Most of meteorology terms in South Korean textbooks are derived from the Chinese characters or imported from foreign language terms are easier for high school students to perceive correct meanings than those of North Korean terms derived from North Korean native language.

• Journal of fish pathology
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• v.29 no.1
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• pp.1-5
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• 2016

Isopods are parasitic crustaceans that pose serious threat to fisheries. Several studies have tried to explore the host-pathogen relationship between marine fishes and isopods. The present study aims to understanding the secondary infections in marine fishes pertaining to isopods. To assess the secondary infection in infected fishes, parasite infested and healthy tissues of fishes were collected. The samples were subjected to standard microbiological procedure to identify the presence of pathogenic bacteria and fungi. Our results showed the branchial region had the higher microbial load of non-sporulating cenocytic fungi in infected fishes. Moreover, fungal strains isolated from the parasitic lesion confirmed that the parasitation and body lesion facilitates the entry of several pathogenic microbes at the damaged host tissue. More over the immune regulation of fish fights back by producing minute cysts, trying to encapsulate the growing fungus. But this may eventually lead to systemic infestation and death of the fish.

• Journal of The Korean Association For Science Education
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• v.26 no.2
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• pp.177-190
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• 2006

Numerous aims of laboratory activities have been suggested by a number of researchers in science education; however the lists of aims very according to researcher. As such, there is still no agreement educational goals on the in science laboratory activities by experts in science education. The purpose of this study was to obtain a consensus using the Delphi technique on the aims of laboratory activities from expert community. This expert community consisted of four scientists, four science educators, six elementary school teachers, and seven secondary school teachers. The list of aims obtained from the expert community were tested with the Wilcoxon Signed Rank Test to determine whether IQR between 2nd and 3rd was convergent. Results of this study produced, lists of aims of laboratory activities according to school science level. There were seven aims for elementary school science, nine aims for secondary school science, and thirteen aims for university science.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.457-458
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• 2008

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.493-499
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• 1997

Many science teachers can be able to miswrite the vocabularies for seven kinds of experimental tool names on blackboard of secondary school in Korean language. The diagnosis test for the miswriting possibility was carried out by science teachers in secondary school. We questioned "How can you write each of Korean vocabulary for seven experimental tools?" to each of one hundred and fourty science teachers in three class of physics, chemistry, and biology during inservice training course of Gyeongsang National University on August in 1997. First of all, for the investigation we showed the real things of seven tools to the teachers and they wrote each vocabulary for each tool name on blackboard in English. In addition we explained the general use of each tool name. And then the teachers answered the vocabularies of them on one written paper. The miswriting results for seven tools were as follows. There appeared various miswriting vocabularies for each tool name. For examples, meas cylinder was miswritten two kinds of Korean name and the miswriting ratio of 4%, Mortar & pestle was miswritten four kinds of name and the ratio of 12%, Beaker & desiccator were miswritten one kind of name and the ratio of 51% and 36%, separately. Separatory funnel & spuit were miswritten two kinds of name and the ratio of 54% and 58%, separately. Schale was miswritten four kinds of name and the ratio of 51%. We might conclude that the cause of miswriting vocabularies for the tool name could be due to the original miswriting in Korean-English or English-Korean dictionaries as well as the seience teachers by themselves.

• Journal of Korean Library and Information Science Society
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• v.49 no.3
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• pp.55-75
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• 2018

The purpose of this study is to identify characteristics of secondary school teachers' perceptions and experiences of school libraries and to suggest strategies for its' activation. In order to achieve this aim, the questionnaire survey was conducted for 229 secondary school teachers who participated in K university qualification training in 2017. As a result, they recognize that school libraries are an essential facility and that continuous support and investment are needed. They think that the effectiveness of the school library is very helpful for creating a leisure and cultural life and for stimulating reading atmosphere and education, and this perception is stronger at lower ages. The number of school library use of them is as low as once a month, and the purpose of use is mainly for cultivation and leisure. The discomfort of the school library is mostly due to lack of materials and space for them. In particular, they have a lack of knowledge and necessity about the method of library-based instruction and insufficient preparation time and poor materials. Teachers are highly aware of the need and utility of training, and prefer training with peers. Therefore, it is necessary to develop strategies such as remodeling space and increasing collections for their study and instruction, and foster peer supervision so that they can actively utilize school library in subjects management.

• Journal of Electrochemical Science and Technology
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• v.11 no.1
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• pp.26-32
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• 2020

In this study, the side reactions that greatly affect the coulombic efficiency of a zinc-air secondary battery are quantitatively analyzed on the basis of the charging-discharging characteristics, open circuit self-discharge characteristics, and a series of calculations. In particular, the charge amounts consumed by water electrolysis and self-discharge during charging process are separately determined so that the charging efficiency (the amount of charge used in actual charging with respect to the applied charge amount) can be estimated, which would enable systematic understanding of the cause of coulombic efficiency degradation. Using two cells with different charging overvoltages, the validity of the proposed method can be assessed.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.224-238
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• 2019

The purpose of this study is to analyze the perception of integrated school education and education for sustainable development of secondary school science teachers, judging that the existence of a common science teacher qualification certificate is related to the expertise of the common science map. To that end, the survey was conducted for three months from June to August 2018 for secondary school science teachers, and multiple choice questions were analyzed as statistical processing and descriptive questions as topical modeling. According to the analysis, teachers with a common science teacher qualification certificate had a high awareness of integrated school education, and the response average was high in all areas of value, direction and success condition of integrated school education. In addition, the average response of teachers with a common science teacher qualification certificate was also found to be higher than those with a common science teacher qualification. There were no major differences in perception between the two groups on the strength of science education and ESD integration, but the difference was that teachers with a common science teaching certificate focused on science in all topics and recognized science as a medium for each topic compared to teachers who did not.

• Journal of The Korean Association For Science Education
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• v.9 no.1
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• pp.75-89
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• 1989

Secondary schools in Korea have been faced with several critical problems with regard to science education. Among them one of the most fundamental problems is associated with laboratory-based science education. There fore as a part of research project for the improvement of science education in secondary schools, this study had its abjectives to inquire into the following areas related to laboratory experiment. ${\circ}$Survey and analysis of theoretical backgrounds for science teaching focused on laboratory experiments. ${\circ}$Status survey of experiment-based science teaching in high schools. ${\circ}$Development of model for improving experiment-based science teaching. In order to fulfill these objectives this study used methods of eiterature review, survey, and interviews. The major finding are as follows : ${\circ}$Some topic for laboratory experiments as oppeared in the textbooks are not appropriate in the light of sience curricular operations in high schools. ${\circ}$In some schools equipments and facilities of school laboratories are for from sufficiency. ${\circ}$Laboratory experiments are not financially supportel for ideal science teach in both middle schools and high schools. These are not on exhaustive list of findings from this study More finding and teaching model for improvement of science education are also described in this paper.