• Education of Primary School Mathematics
• /
• v.6 no.2
• /
• pp.85-91
• /
• 2002

The purpose of this study is to analyze elementary students' understanding the relationship between perimeter and area in geometric figures. In this study, the questionaries were used. In the survey, the subjects were elementary school students in In-cheon city. They were 86 students of the fifth grade, 86 of the sixth. They were asked to solve the problems which was designed by the researcher and to describe the reasons why they answered like that. Study findings are as following; Students have misbelief about the concept of the relationship between perimeter and area in geometric figures. Therefore, 1 propose the method fur teaching about the relationship between perimeter and area in geometric figures. That is teaching via problem solving.. In teaching via problem solving, problems are valued not only as a purpose fur learning mathematics but also a primary means of doing so. For example, teachers give the problem relating the concepts of area and perimeter using a set of twenty-four square tiles. Students are challenged to determine the number of small tiles needed to make rectangle tables. Using this, students can recognize the concept of the relationship between perimeter and area in geometric figures.

• Communications of Mathematical Education
• /
• v.24 no.3
• /
• pp.627-658
• /
• 2010

The introduce and accurate understanding of the concept of tangent line is very important in Mathematics education and its applications. In this study, we investigated the introduction method in the textbook for tangent line and its concepts. And we studied the effective teaching methods for the accurate understanding using Lakatos learning theory, GSP and related precedence studies. Finally we suggest the teaching plan for the equation of for the tangent line in the high school and apply to the High school students.

• Journal of the Korean Ceramic Society
• /
• v.45 no.1
• /
• pp.1-29
• /
• 2008

In last two decades, an impressive progress has been recorded in terms of developing new materials or refining existing material composition/microstructure in order to obtain better performance in biomedical applications. The success of such efforts clearly demands better understanding of various concepts, e.g. biocompatibility, host response, cell-biomaterial interaction. In this article, we review the fundamental understanding that is required with respect to biomaterials development, as well as various materials and their properties, which are relevant in applications, such as hard tissue replacement. A major emphasize has been placed to present various design aspects, in terms of materials processing, of ceramics and polymer based biocomposites, Among the bioceramic composites, the research results obtained with Hydroxyapatite (HAp)-based biomaterials with metallic (Ti) or ceramic (Mullite) reinforcements as well as $SiO_2-MgO-Al_2O_3-K_2O-B_2O_3-F$ glass ceramics and stabilized $ZrO_2$ based bioinert ceramics are summarized. The physical as well as tribological properties of Polyethylene (PE) based hybrid biocomposites are discussed to illustrate the concept on how can the physical/wear properties be enhanced along with biocompatibility due to combined addition of bioinert and bioactive ceramic to a bioinert polymeric matrix. The tribological and corrosion properties of some important orthopedic metallic alloys based on Ti or Co-Cr-Mo are also illustrated. At the close, the future perspective on orthopedic biomaterials development and some unresolved issues are presented.

• Journal of Korean Society of Rural Planning
• /
• v.16 no.2
• /
• pp.57-64
• /
• 2010

This study aims to understand the degree of inequality of surveyed amenity resources and identify which resource and region have the highest concentration by estimating Lorenz Curve and the Gini's Coefficient. The Lorenz Curve and Gini's Coefficient derived from economics are introduced as tools for investigating and quantifying regional variability of amenity resources concentration. This study describes the concepts underlying the application of the Gini's coefficient to measure the concentration of amenity resources in 11 regions, Chungbuk Province, Korea. The Lorenz Curve presents a graphical view of the cumulative distribution of amenity resources and the Gini's Coefficient provides a single-parameter measure of the distributional concentration of amenity resources. Also the Gini's Coefficient is compared to the number of amenity resource for understanding distributional difference between concentration and quantitative distribution of amenity resources. The results demonstrate significantly different regional variation according to the amenity variables: almost intact nature, interaction between nature and man, man-made.

• International Journal of Advanced Culture Technology
• /
• v.10 no.1
• /
• pp.170-179
• /
• 2022

To find out the effect of interest on chemical content, interest in chemistry, choice of science elective subjects, teaching-learning characteristics that make it difficult to understand contents, academic achievement in general chemistry according to university admission screening, etc. were surveyed on 51 students enrolled in the department of chemistry education at P college of education. As a result of the survey, it was found that the interest in Chemistry I, Chemistry II, and general chemistry increased significantly to 94.6%, 73.7%, and 66.0%, respectively. 39.3% of the students answered that they had a lot of difficulty in understanding general chemistry. The characteristics of learners who make it difficult to understand the content were found to be 'lack of willingness to learn' such as 'lack of understanding chemical concepts' and 'lack of problem solving', due to the lack of 'basic knowledge'. As a way to solve these difficulties, 'expert help' appeared the most. The grades of general chemistry of students who entered the regular admission were relatively higher than those of occasional recruitment.

• Journal of the Korean School Mathematics Society
• /
• v.25 no.1
• /
• pp.79-104
• /
• 2022

It is very important to help students learn by examining how well students solve math problems. Therefore, in this study, four methods(error analysis by problem type, schematization analysis, area graph analysis, and broken line graph analysis) were constructed to analyze how the connectivity between concepts of middle school functions affects the problem solving results. The students' learning situation was visually expressed to enable intuitive understanding. This analysis method makes it easy to understand the evaluation results of students. It can help students learn by understanding their learning situation. It will be useful in mathematics teaching and learning as it can help students to monitor their own problems and make a self-directed learning plan.

• International Journal of Computer Science & Network Security
• /
• v.22 no.5
• /
• pp.115-120
• /
• 2022

New realities of social relations are changing the understanding of certain phenomena, including the emergence of new concepts among the objects of property rights, such as: virtual assets, and the circulation of virtual assets. The rapid development of the virtual assets market involves the legislative consolidation of the status of such assets, changes in taxation, their circulation, and so on. These circumstances increase the interest in the study of virtual assets as the latest object of property rights and necessitate the study of this topic. The work aims to explore the theoretical developments and regulations on virtual assets in the modern world, as well as to summarize the conclusions about virtual assets as the latest object of property rights. The object of research is the content of the concept of "virtual asset" and its legal status. The methodology of work is represented by a set of methods and techniques that were used to achieve this goal, namely: hermeneutic, historical, extrapolation, comparative law, generalization, analysis, synthesis, and deduction. The study analyzed different approaches to understanding virtual assets, analyzed the characteristics of virtual assets, and concluded that in today's conditions there is no single unified legal regulation of virtual assets, although many countries are moving towards consolidating the status of virtual assets.

• Research in Mathematical Education
• /
• v.25 no.3
• /
• pp.201-225
• /
• 2022

This paper details case study vignettes that focus on enhancing the teaching and learning of geometry and measurement in the elementary grades with attention to pedagogical practices for teaching through problem solving with rigor and centering equitable teaching practices. Rigor is a matter of equity and opportunity (Dana Center, 2019). Rigor matters for each and every student and yet research indicates historically disadvantaged and underserved groups have more of an opportunity gap when it comes to rigorous mathematics instruction (NCTM, 2020). Along with providing a conceptual framework that focuses on the importance of equitable instruction, our study unpacks ways teachers can leverage their deep understanding of geometry and measurement learning trajectories to amplify the mathematics through rigorous problems using multiple approaches including learning by doing, challenged-based and mathematical modeling instruction. Through these vignettes, we provide examples of tasks taught through rigorous problem solving approaches that support conceptual teaching and learning of geometry and measurement. Specifically, each of the three vignettes presented includes a task that was implemented in an elementary classroom and a vertically articulated task that engaged teachers in a professional learning workshop. By beginning with elementary tasks to more sophisticated concepts in higher grades, we demonstrate how vertically articulating a deeper understanding of the learning trajectory in geometric thinking can add to the rigor of the mathematics.

• Journal of the Korean Chemical Society
• /
• v.67 no.2
• /
• pp.89-98
• /
• 2023

The cell membrane, also known as the biological membrane, surrounds every living cell. The main components of cell membranes are lipids and therefore called as lipid membranes. These membranes are mainly made up of a two-dimensional lipid bilayer along with integral and peripheral proteins. The complex nature of lipid membranes makes it difficult to study and hence artificial lipid membranes are prepared which mimic the original lipid membranes. These artificial lipid membranes are prepared from phospholipid vesicles (liposomes). The liposomes are formed when self-forming phospholipid bilayer comes in contact with water. Liposomes can be unilamellar or multilamellar vesicles which comprises of phospholipids that can be produced naturally or synthetically. The phospholipids are non-toxic, biodegradable and are readily produced on a large scale. These liposomes are mostly used in the drug delivery systems. This paper offers comprehensive literature with insights on developing basic understanding of lipid membranes from its structure, organization, and phase behavior to its potential use in biomedical applications. The progress in the field of artificial membrane models considering methods of preparation of liposomes for mimicking lipid membranes, interactions between the lipid membranes, and characterizing techniques such as UV-visible, FTIR, Calorimetry and X-ray diffraction are explained in a concise manner.

• Educational Technology International
• /
• v.9 no.2
• /
• pp.17-37
• /
• 2008

This study is to examine different views of teachers, students, parents and experts on existing mathematics textbook and ideas and alternatives for developing new textbooks. We interviewed deeply with 18 teachers, 18 students, 9 parents, and 4 experts and analyzed two analysis frame categories; Strengths and weaknesses of current textbooks and directions of mathematics textbooks that will be revised. We found that among teacher, student, parent and expert, there are some differences of meaning about mathematics textbooks, based on interview questions. The directions of new textbooks are as follows. First, 'the definitions of mathematics textbook concepts' shared and sympathized by teachers, students, parents, and experts should be considered in developing the textbooks. Second, the textbooks should be much usable in classrooms and be matched to the goals of mathematics subjects. Third, the contents and levels of difficulty of the textbooks should be based on the specific objectives and the analysis of curriculum and its contents. Fourth, understanding students should be presupposed as the external side of contents and the textbooks themselves should be associated with the image of joyful and fun mathematics. Fifth, the mathematics textbooks should reflect real daily life to their contents and be linked to other subjects.