• Journal of The Korean Association For Science Education
• /
• v.43 no.6
• /
• pp.533-547
• /
• 2023

This study is an action research aimed at improving the instruction of a teacher educator who teaches science teaching methods to elementary preservice teachers. After identifying the cause of their low levels of curiosity and interest in physics, teaching plans addressing this problem were explored, applied to classes, and reflected upon. Through this process, ways to improve teaching practice in science classes for elementary preservice teachers and pique their scientific curiosity and interest were proposed. A spiral implementation structure that repeats implementation and reflection a total of three times was designed for the prospective preservice teachers who participated in elementary science textbook research physics classes. Self-reports, student participation data, and results from both peer and self-evaluations were collected and analyzed. The reasons for the preservice teachers' low levels of curiosity and interest in science were identified as their inability to recognize and express information gaps and their low levels of willingness to resolve this. Practice expressing information gaps, raising the level of knowledge to be able to recognize information gaps, and a strategy to have the will to resolve information gaps were introduced into the class. To the extent that changes can be made by improving unit classes, elementary preservice teachers can express their curiosity and interest in science through this process.

• Journal of Soil and Groundwater Environment
• /
• v.28 no.6
• /
• pp.71-89
• /
• 2023

A groundwater potential map (GPM) was built for the Nakdonggang River Basin based on ten variables, including hydrogeologic unit, fault-line density, depth to groundwater, distance to surface water, lineament density, slope, stream drainage density, soil drainage, land cover, and annual rainfall. To integrate the thematic layers for GPM, the criteria were first weighted using the Analytic Hierarchical Process (AHP) and then overlaid using the Technique for Ordering Preferences by Similarity to Ideal Solution (TOPSIS) model. Finally, the groundwater potential was categorized into five classes (very high (VH), high (H), moderate (M), low (L), very low (VL)) and verified by examining the specific capacity of individual wells on each class. The wells in the area categorized as VH showed the highest median specific capacity (5.2 m³/day/m), while the wells with specific capacity < 1.39 m³/day/m were distributed in the areas categorized as L or VL. The accuracy of GPM generated in the work looked acceptable, although the specific capacity data were not enough to verify GPM in the studied large watershed. To create GPMs for the determination of high-yield well locations, the resolution and reliability of thematic maps should be improved. Criterion values for groundwater potential should be established when machine learning or statistical models are used in the GPM evaluation process.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2023.11a
• /
• pp.72-73
• /
• 2023

As containerized maritime transport began in earnest, the size of container ships has steadily increased, and recently, the operation of 24,000 TEU-class vessels has become regular. However, concerns about the efficiency and productivity of such mega container ships from a port operational perspective have continued to be raised. The 10th Busan International Port Conference requested an in-depth study on the trends of container ship enlargement by analyzing the order status of ultra-large container ships from major global liners. Generally, the factor that drives the upsizing of ships is the realization of economies of scale that lowers transportation costs per TEU, which leads to a higher level of cost reduction per unit transportation compared to the increase in fuel consumption due to transporting large amounts of cargo with a single ship. However, it is necessary to examine whether this trend of container vessel enlargement is feasible for port operations. To this end, this study compares and analyzes the productivity and efficeiency of different ship sizes to evaluate the effect of ship size on port operations.

• Journal of The Korean Association For Science Education
• /
• v.29 no.1
• /
• pp.116-136
• /
• 2009

Since there are differences in the content, structure and functions of interpersonal communication during the practice of school science classes, it needs to articulate the difference of the modality of pedagogical practice in order to understand science teaching in detail. These characteristics of science teaching can be investigated by further insightful analysis on language in the science classroom. In this study, classroom discourse language codes using Bernstein's code theory were analyzed in the case of a middle school science class on the unit of minerals. The discourse language code was identified by the value of classification, which revealed power relations to the contexts of discourse and participants of discourse. It was also identified by the value of framing, which showed hierarchical relation between teacher and students as discourse subjects, and discursive control on the initiative of discourse. The results addressed that six types of discourse language codes were constructed and that those language codes reflected diverse modalities of science teaching from student-centered instruction to teacher-centered instruction in relation to classroom discourse. The modality of science teaching according to the transition tendencies of discourse language code showed dynamic variations of 'controlled student-centeredness inducing teaching' - 'positional student-centeredness permissive teaching' - 'controlled students' participation permissive teaching' - 'controlled student-centeredness facilitative teaching' - 'student-centeredness enhancing teaching'. In addition, results released that discursively and hierarchically weak control of discourse is necessary for enhancing student-centeredness of science teaching. Moreover, teaching practice enhancing student-centeredness can be accomplished by the harmony of a teacher's perception of discourse language code and his/her orientation to constructivist teaching and student-centered teaching.

• Journal of The Korean Association For Science Education
• /
• v.29 no.6
• /
• pp.611-625
• /
• 2009

The purpose of this research is to investigate the characteristics of beginning science teachers' subject matter knowledge (SMK) as revealed in their classroom teaching methods. In this research, we explored six beginning teachers' classroom teaching episodes on the 'work and energy' unit. Using open-ended interviews with the teachers and group discussions taking place on a regular basis to analyze and compare the classes of six beginning teachers, we extracted the features of beginning science teachers' SMK. Using grounded theory methods, the characteristics of beginning science teachers' SMK drawn from this research are: (1) beginning teachers' positivistic epistemology on science, (2) claiming the teacher's authority based on rich subject content knowledge, and (3) beginning teachers' science elitism. These epistemological characteristics are realized such PCK as (1) representational errors caused by the teacher's own science misconception, (2) doing harm to students with too much content knowledge, (3) sporadic content presentation lacking a focus, and (4) surplus class hours with lack of effective science teaching explanations. Suggestions for alternative perspectives on science SMK are presented by experienced teachers. In conclusion, science teachers' SMK is necessary, but not sufficient, for effective teaching. Science teachers' SMK does have an effect on science teaching, mediated by other types of teacher knowledge. The beginning teachers need a systematic support to transform their SMK into a viable PCK.

• Journal of The Korean Association For Science Education
• /
• v.28 no.2
• /
• pp.120-129
• /
• 2008

In this study, 17 formative assessments using cartoon were developed for studying 'genetics and evolution' chapter in textbook of third grade of junior high school. And those were applied to 73 students in experimental group and 78 students in control group. We investigated if there was positive effect on students' perception, attitude about assessment and scholastic achievement. As a result, we could find the formative assessments using cartoon were effective to change students' negative perception and attitude to positive one. Especially, those were effective to make students to understand usefulness of assessment (p<.05), and to decrease a feeling of uneasiness about assessment (p<.01). Also, we could find the developed formative assessments using cartoon had more positive effect on raising scholastic achievement than formative assessment using descriptive passage (p<.05). It was considered that this was because the abstract concepts of 'genetics and evolution' chapter were described in pictures, so contexts of textbook and assessment questions became easier to understand. So, we could conclude that formative assessment using cartoon contributed to increase students' understanding of contexts of textbook and to increase their interests about study. And if this assessment method is applied to class actively, students' feeling of uneasiness about assessment can be easily overcome and it can also give them positive perception about assessment.

• Journal of The Korean Association For Science Education
• /
• v.28 no.8
• /
• pp.901-921
• /
• 2008

The purpose of this study was to investigate elementary teachers' views on the barriers in implementing inquiry-based instruction in science education. For this, semi-structured in-depth interviews were performed with 22 elementary school teachers who have served for more than five years in the Gyeonggi province. The interview questions were developed through triangulation of Seidman's phase to achieve reliability in the interview data, then interview questions were modified and completed through an analytic induction method in pre-interviews. In-depth interviews were performed individually and all the interviews were recorded. The data of teachers' views on the barriers were categorized and analyzed into external and internal factors of teachers. The study found that the external factors referred by teachers included the following; the lack of a unit time, lack of materials and equipments, too many students in a class, problems in science curriculum management, difficulty in the assessment of students' inquiry activities, the students' learning, lack of opportunities for teaching inquiry activities, harmfulness of accidents, and so on. Internal factors included the following; lack of preparation for inquiry activities, lack of self-confidence, lack of patience, and so on. The various barriers presented and their causes were analyzed in detail, and possible efforts in activating inquiry activities in elementary science education were suggested.

• Journal of the Korean Chemical Society
• /
• v.68 no.2
• /
• pp.93-106
• /
• 2024

This study investigated differences in presence, immersion, and situational interest in small group learning using augmented reality, based on the degree of tool sharing. 84 eighth-grade students participated in small groups of four. Each group was randomly assigned to one of three environments based on marker and device sharing: the shared environment (shared marker and device usage), the mixed environment (shared marker and individual device usage), and the individual environment (individual marker and device usage). Small group learning using augmented reality was conducted for three class periods, focusing on the "Characteristics of Matter" unit. One-way ANOVA results for the dependent variables revealed that, compared to the shared environment, presence and situational interest were significantly higher in the mixed environment, while immersion and situational interest were significantly higher in the individual environment. MANOVA results for the sub-components of each dependent variable showed significant differences in realness for presence, antecedents and experiences for immersion, and instant enjoyment, novelty, and total interest for situational interest. Analysis of interviews and classroom observations indicated that students in shared and individual environments tended to use their devices individually when utilizing augmented reality. However, in mixed environments, students showed a tendency to use their devices collaboratively, leading to more active interactions. Based on these findings, environments for using tools to enhance the effectiveness of small group learning using augmented reality are discussed.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.4
• /
• pp.365-372
• /
• 2024

The South Korean marine industry is emerging as a significant market, driven by the growing popularity of various water leisure activities, including sailing. This trend suggests a rising demand for sailing yachts. Consequently, since 2022, the design and development of a 28ft sailing yacht have been ongoing, supported by the government and the Ministry of Oceans and Fisheries, to promote yachting culture in South Korea. The Velocity Prediction Program (VPP) analysis was conducted using WinDesign during the preliminary design stage to evaluate performance and determine design parameters. The hydrodynamic model used for this vessel is based on regression methods developed from years of experience in naval architecture and yacht research at the Wolfson Unit, providing reliable estimates for most modern yachts. However, owing to the lack of specific hydrodynamic data from towing tank tests or CFD numerical analysis, verification of the hydrodynamic model has faced some challenges. Additionally, an incomplete weight estimate resulted in variable VCG values, potentially affecting stability and overall performance. The optimal boat speed for this vessel was determined at true wind speeds (TWS) of 4, 8, 12, 16, and 20 knots, using both the jib (up to 120° TWA) and the spinnaker (from 80° TWA). The optimized speed of the yacht was found to be comparable to that of international similar-class yachts.

• The Journal of Korean Academy of Prosthodontics
• /
• v.62 no.3
• /
• pp.215-223
• /
• 2024

The patient in this case presented with a desire to have new dentures due to discomfort with existing ones. At the initial visit, all of teeth were missing except for the mandibular left second molar. As the patient was 65 years old, treatment with dentures and implant-supported prostheses was possible under the national health insurance system, and the patient opted for the mandibular denture using implant. Temporary prostheses were initially provided for patient adaptation, and following successful adaptation period, the treatment progressed. A maxillary complete denture and a mandibular implant-supported denture using two implants in the canines were fabricated. The mandibular denture is a Kennedy Class II removable partial denture which consists of a six-unit porcelain fused to metal fixed dental prostheses supported by the implant in the canines on both sides and left second molar serving as the abutments. Despite severe bone resorption and insufficient abutment teeth, the patient expressed satisfaction with the treatment results. In cases with economic and anatomical constraints affecting the feasibility of complete denture, implant-supported overdenture, and implant-supported fixed dental prostheses, an implant-assisted removable partial denture using implant surveyed crowns proves to be a viable and effective alternative treatment option. Nevertheless, the current dearth of scientifically rigorous studies underscores the necessity for meticulous regular check-up and occlusal assessment.