• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 1999.11b
• /
• pp.130-139
• /
• 1999

In order to manage the wet end chemistry on paper machines, our goal is to control sub-processes through which we can influence the entire wet end operations with maximum effect. The most important sub-processes are: consistency, ash, and chemistry. The management of these three main groups is based on on-line maesurements and automatic control. This paper presents a new wet end management platform, a new analyzer. This new analyzer utilizes a modular structure and modem software. It is part of a new paper machine concept. The controls of this concept are feedback and feedforward solutions that control retention, consistencies, ash, and charge, resulting in a more stable wet end (30...80%), more uniform paper, and better rnnability.

• Journal of the Korean Chemical Society
• /
• v.51 no.1
• /
• pp.65-72
• /
• 2007

The purpose of this study was to examine the 7th national science curriculum (chemistry domain) regarding the meanings of ‘mulgil' (Korean), the particulate nature of matter, and the state of matter. It was found that the term of ‘mulgil' was being used vaguely as representing material, matter, or substance without clear definition. This was problematic by reason that it could hinder students from having the concept of substance. Regarding the particulate nature of matter, molecule was introduced as a basic unit of matter at grade 7, prior to atom and ion, which were introduced at grade 9 and 10, respectively. It is necessary to reconsider the sequence of each particle concept to provide students with more consistent and comprehensive understanding of structure of matter. In the case of change of state, key concepts such as conservation of matter or reversibility were omitted in the curriculum document, and explanations based on various aspects of particles were somewhat insufficient. The concept of matter is fundamental to chemistry, and we must recognize it as a concept that needs to be taught clearly. Implications for curriculum revision were discussed.

• Journal of the Korean Chemical Society
• /
• v.64 no.1
• /
• pp.19-29
• /
• 2020

We analyzed the representations of acid-base models in 4 kinds of Chemistry I and 4 kinds of Chemistry II textbooks of the 2009 revised curriculum, and 9 kinds of Chemistry I textbooks and 6 kinds of chemistry II textbooks of the 2015 revised curriculum in this study. The problems of the textbook were divided into the problems of definitions and the representations of the logical thinking. As a result of the study, the lack of the concept of chemical equilibrium had a problem with the representation of reversible reactions in the definition of the Brønsted-Lowry model in the Chemistry I textbooks of 2009 revised curriculum, it also appeared to persist in Chemistry I textbooks of 2015 revised curriculum which contains the concept of chemical equilibrium. The representations of logical thinking were related to particle kinds of conservation logic, combinational logic, particle number conservation logic, and proportion logic. There were few problems related to representation of logical thinking in Chemistry I textbook in 2009 revision curriculum, but more problems of representations related to logics are presented in Chemistry I textbooks in 2015 revision curriculum. Therefore, as the curriculum is revised, the representations of chemistry textbooks related to acid and base models need to be changed in a way that can help students' understanding.

• Journal of The Korean Association For Science Education
• /
• v.22 no.3
• /
• pp.444-454
• /
• 2002

In this study, we analyzed the explanation of the concepts related to osmotic pressure and semipermeable membrane that were represented in chemistry and biology textbooks of high school and general course of college. There were 4 types of explanation in osmotic pressure and 3 types of semipermeable membrane concept. Students can understand the concepts with different meaning because there are different viewpoints on the explanations of the concepts. We must consider the various types of explanation when we design science textbooks because these confusions disturb students' understanding of the concepts.

• Journal of the Korean Chemical Society
• /
• v.51 no.2
• /
• pp.186-192
• /
• 2007

In this study, the effects of concept mapping on the preservice elementary teachers' achievement, conceptual understanding, anxiety toward science, and science teaching efficacy belief were investigated in the undergraduate general chemistry course. The aptitude-treatment interaction (ATI) between preservice teachers' learning approach and concept mapping strategy was also investigated. Sixty-nine freshmen from a university of education were assigned to a control group and a treatment group. Tests regarding students' learning approach, anxiety toward science, and science teaching efficacy belief were administered as pretests. Treatment lasted for 9 weeks. In every class, students in the treatment group constructed concept maps, while those in the control group solved the problems of the textbook after the lecture. After the instructions, tests of achievement, conceptual understanding, anxiety toward science, and science teaching efficacy beliefs were administered. The results indicated that students in the treatment group significantly outperformed those of the control group in the achievement test. In the conceptual understanding and the science teaching efficacy beliefs, however, no statistically significant differences were found between two groups. Students of the treatment group showed significantly higher anxiety than their counterpart in the test of anxiety toward science. No aptitudetreatment interaction between students' learning approach and the concept mapping strategy was found.

• Journal of the Korean Chemical Society
• /
• v.68 no.3
• /
• pp.160-175
• /
• 2024

The purpose of this study is to examine the effects of a Chemistry I class based on an artificial intelligence (AI) classification model. To achieve this, the research investigated the development and application of a class utilizing an AI classification model in Chemistry I classes conducted at D High School in Gyeongbuk during the first semester of 2023. After selecting the curriculum content and AI tools, and determining the curriculum-AI integration education model as well as AI hardware and software, we developed detailed activities for the program and applied them in actual classes. Following the implementation of the classes, it was confirmed that students' self-efficacy improved in three aspects: chemistry concept formation, AI value perception, and AI-based maker competency. Specifically, the chemistry classes based on text and image classification models had a positive impact on students' self-efficacy for chemistry concept formation, enhanced students' perception of AI value and interest, and contributed to improving students' AI and physical computing abilities. These results demonstrate the positive impact of the Chemistry I class based on an AI classification model on students, providing evidence of its utility in educational settings.

• Journal of The Korean Association For Science Education
• /
• v.29 no.8
• /
• pp.898-909
• /
• 2009

In this study, we investigated the influences of the role-playing analogy in chemistry concept learning on mapping understanding and mapping errors by analogical reasoning ability level. Seventh-graders (N=151) at a middle school were assigned to the comparison group and the experimental group. The students of the experimental group were taught with the 'running in the circle' role-playing analogy. After the students were taught about 'the relation between volume and pressure of gas', the test of mapping understanding in the next class and the retention test four weeks later were administered. The students with typical mapping errors were also interviewed to investigate their mapping processes. The results revealed that the role-playing analogy in chemistry concept learning improved mapping understanding and its retention regardless of analogical reasoning ability level. It was also found that the students in the experimental group had fewer mapping errors than those in the comparison group. However, there were similar patterns of mapping errors in both groups, and there were no significant differences in the frequencies of each type of mapping errors by analogical reasoning ability level. Educational implication of these findings are discussed.

• Journal of the Korean Chemical Society
• /
• v.55 no.1
• /
• pp.112-123
• /
• 2011

The chemistry has the academic system in which a concept is jointly developed into the single strain, so the contents of the chemistry I II of the high school are very important in the connection of the general chemistry in the university. At this moment, it is possible for high school graduates to be accepted into science or engineering majors without taking the chemistry II. These the highest intensive election subject cause problems of differences in level of understanding and difficult of quality educations. In this study, we have analyzed similarity between the contents of the chemistry I II and the general chemistry. We also analyzed the cognition level of students without taking the chemistry II in understanding the general chemistry level classes. We found that the high school level chemistry I and II introduced about 27% and 62% of the essential concepts required for the general chemistry, respectively. In a case of M university in Chonnam, about 70% of students in the general chemistry classes have no exposure to the chemistry II in their high schools, causing difficulty of understanding new subjects due to their insufficient concepts for classes. The lack of knowledge caused lowering of learning achievement and decrease of interests in chemistry.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.4 no.2
• /
• pp.121-123
• /
• 2018

Fluoride is one of most important atoms for both clinical and pharmaceutical usage. Associated with such a strong need, $^{18}F$-fluoride has been widely used as an essential radioisotope. The fluoride always suffers from strong solvation effects through strong hydrogen bonding, which reduce the reactivity of fluoride anion. To enhance the reactivity, the concept of naked fluoride was introduced in the fluorination field. In this essay, I will briefly describe the history of naked fluoride concept and development of naked fluoride sources.

• Journal of the Korean Chemical Society
• /
• v.55 no.6
• /
• pp.1030-1041
• /
• 2011

We investigated the understanding of pre-service science teacher about the chemistry concept of middle school curriculum using some items in National Assessment of Educational Achievement and analyzed the result according to background variables of pre-service science teacher. The result was that there were some pre-service science teachers who select incorrect answer at all items, pre-service science teachers don't fully understand the concept needed to solve item. And the percentage of correct answer at some items was low regardless of selection of chemistry as an elective subject at CSAT(College Scholastic Ability Test). We found some facts through the depth interviews to find the cause of the result. First, the misconception acquired in middle school days is tend not to change until college student. Second, the formation of misconception is affected by the study habit with which solve problem by simple calculation and memory without essential understanding. Third, the study habit with which solve problem by simple calculation and memory without essential understanding could not replace misconceptions acquired in middle school days with scientific concept regardless of selection of chemistry as an elective subject at CSAT.