• Smart Media Journal
• /
• v.9 no.2
• /
• pp.51-62
• /
• 2020

Starting with the "Smart Grid National Road Map" in 2010, the Smart Grid 2030 was introduced through the basic plan and implementation plan of the intelligent power grid with the goal of building the world's first national smart grid. In this paper, we intend to build a power domain ontology based on the power business platform based on the upper and lower conceptual models of the "Smart Grid Interoperability Standard Framework and Roadmap", the standard of implementation plan. Ontology is suitable for expressing and utilizing the smart grid conceptual model because it considers hierarchical structure as knowledge defines the properties of entities and relationships between entities, but there is no research related to them. Therefore, in this paper, the upper ontology was defined as a major category for smart grid-related fields, and the lower ontology was defined as detailed systems and functions for the upper ontology to construct the ontology. In addition, scenarios in various situations that could occur in the power system were constructed and significant inference results were derived through inference engines and queries.

• Journal of Oral Medicine and Pain
• /
• v.37 no.2
• /
• pp.93-105
• /
• 2012

Let me introduce a teaching method to improve practice capacity in dental laboratary work. I applied theories of layers of modeling and reflection constituting cognitive apprenticeship and peer tutoring to my class. At internet uploading a file showing a practice procedure a week before the class of a course, I let students preview it. During the class I demonstrated the practice procedure in front of students. A superior student and an inferior student paired according to the previous practice grade and a feedback between a peer tutor and a peer tutee was activated. Late in the class, a student self-evaluated his own practice result and had a check of a professor. Finally he compared his own practice result with that in the file uploaded at internet and reflected. This teaching method led to improvement in students' satisfaction and efficiency of learning.

• Journal of Korean Home Economics Education Association
• /
• v.31 no.4
• /
• pp.81-95
• /
• 2019

This study examined the research trends of sustainable development education in the family life area, focusing on papers published in journals specialized in the Practical Arts (Technology & Home Economics) subject from 1989 to 2018. The papers from three journals were selected based on the titles, abstracts, and keywords for their contents related to sustainable development education. The results were analyzed by frequency analysis and cross-tabulation. Sustainable development education has surged since the mid-2000s when national interest on this topic sharply increased. Rather than focusing on particular content areas in home economics, most research was conducted through an integrated approach. More than half of the studies were conducted in experimental studies, with the largest number of studies involving elementary school students. Of the three components of ESD, research on society was most frequently conducted, followed by the environmental area. The contents of the home economics curriculum and the details of sustainable development were related. More related research should be conducted so that various sustainable development education can improve students' practical problem-solving ability through Practical Arts (Technology & Home Economics) curriculum.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.2D
• /
• pp.237-245
• /
• 2011

Asphalt Plug Joint(APJ) is a new type of expansion joint that it's application are increased in USA as well as several European countries. APJ's' advantages are cheap construction and maintenance costs, and simple construction and securing of excellent flatness. However, APJ's usability is hindered because it showed a problem of premature failure. Research for solving this problem has been progressed, and FEM analysis among existing researches was peformed. However, the behavior of APJ was insufficiently analyzed and the reliability of the analysis was much low, since the material showing complicated behavior was oversimplified, Therefore, a material model was proposed and its effectiveness was confirmed by comparing it with actual behavior in order to improve the reliability of FEM analysis in this paper. ABAQUS program was used for FEM analysis, and an elasto-plastic model and a viscous-plastic model as the material model of APJ were suggested on the base of experiment results of APJ material performed by Bramel et al. The elasto-plastic model was defined by time-independent analysis since it didn't consider time and strain rate, and the viscous-plastic model was defined by time-dependent analysis since it considered. Influence of various elements affecting the behavior of APJ was investigated, and it was confirmed that the time-dependent analysis showed better result closed to actual behavior than the time-independent analysis.

• The Journal of Bigdata
• /
• v.5 no.1
• /
• pp.155-180
• /
• 2020

It takes the most important role the problem of assigining vehicles and desigining optimal routes for each vehicle in order to enhance the logistics service level. While solving the problem, various cost factors such as number of vehicles, the capacity of vehicles, total travelling distance, should be considered at the same time. Although most of logistics service providers introduced the Transportation Management System (TMS), the system has the limitation which can not consider the practical constraints. In order to make the solution of TMS applicable, it is required experts revised the solution of TMS based on their own experience and intuition. In this research, different from previous research which have focused on minimizing the total cost, it has been proposed the methodology which can enhance the efficiency and fairness of asset utilization, simultaneously. First of all, it has been adopted the Cluster-First Route-Second (CFRS) approach. Based on the location of customers, we have grouped customers as clusters by using four different clustering algorithm such as K-Means, K-Medoids, DBSCAN, Model-based clustering and a procedural approach, Fisher & Jaikumar algorithm. After getting the result of clustering, it has been developed the optiamal vehicle routes within clusters. Based on the result of numerical experiments, it can be said that the propsed approach based on CFRS may guarantee the better performance in terms of total travelling time and distance. At the same time, the variance of travelling distance and number of visiting customers among vehicles, it can be concluded that the proposed approach can guarantee the better performance of assigning tasks in terms of fairness.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.1
• /
• pp.321-326
• /
• 2020

This paper is to analyze the language education policy in the context of multilingualism. As the majority of the population are multilingual, language policy should be centered on the multilingual speakers as the norm, and multilingual language policy is the best route which we can follow as a language policy in education. The motivation and legitimacy of the multilingual policies are suggested in terms of 6 different perspectives: identity, sustainability, equity, World Englishes, machine translation, and Universal Grammar (UG). As a model of language policy, the English-Plus (i.e., English+n) policy and similarly the Korean-Plus (i.e., Korean+n) policy are suggested to be the most appropriate language policies in the field of education in America and Korea respectively. These plus policies aim at bilingual fluency in both the native language and other foreign languages that are constitutive of the multilingualism of the country in which the bilingualism is treated as a variant of multilingualism. In a period of convergence and diversity in the 4^th Industrial Revolution, language diversity and multilingual policy should be considered as a right to be protected or as a resource to be conserved rather than as a problem to be solved.

• Journal of The Korean Association For Science Education
• /
• v.32 no.10
• /
• pp.1613-1626
• /
• 2012

The purpose of this study was to develop an effective mentoring program model. In order to develop an effective mentoring program, we identified four elements of mentoring program based on the analysis of secondary science teachers perceptions of in-service science teacher training program and mentoring. For the study, a questionnaire was developed by the authors and it was administrated to 114 secondary science teachers participated in science teacher training program. The interviews were conducted with 14 secondary science teachers. The results of this study are as follows: Most of the secondary science teachers recognized that in-service science teacher training program, which they had taken, positively affected their teaching. However, there are some aspects needed for improvements in the current teacher training program. They wanted to take the opportunities to interact with their colleagues and researchers, sharing their experiences on teaching within the teachers' community, and reflecting on their own teaching. Based on these analysis we suggest four elements for effective mentoring program. These are 'Communication,' 'Reflection for Mentor,' 'Reflection for Mentee,' and 'Evaluation.' In addition, the mentoring program is proposed to consist of four activities such as 'Feedback on teaching', 'Seminar and Workshop', 'Conference', and 'Self-evaluation'.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.3
• /
• pp.109-119
• /
• 2011

The virtual reality (VR) technology has been used as the application of architectural presentation or simulation tool in the field of industry. The high immersion and intuitive visual information are the great merits of design evaluation or environmental simulation when we are using the virtual environments. But the distortion of distance perception in VR is still a big problem when the accuracy of distance presentation is strictly required. For example, distance estimation is especially important when the virtual environments are applied to the presentational tool for evaluation the space design or planning in the field of architecture. If there are some perception error between the built space in real and represented space in virtual, the accurate design evaluation or modification of design is hard to be carried out during the design development stage. In this paper, we have carried out some experiments about distance estimation in the immersive virtual environments to verify the factors and their influence. We made a hypothesis that the lack of the information for the user in VR causes the different distance estimation from the real world because users are usually comfortable with moving fast and long distance in VR environments compared with moving slow and short distance in real space. So, we carried out basic experiment to prove our hypothesis that the lack of information makes subjects estimate the distance of walking in VR shorter compared with the same distance in real. Also, among the factors that probably affect the distance estimation in VR, we have verified the influence of the image resolution. The influence of resolution degradation of image on the distance estimation was verified with the condition of static and dynamic images. The results showed that the resolution has deep relation with the distance estimation. For example, the subject underestimated the distance at the lower resolution condition. We also found the methods of the making the lower resolution image could affect on the visual perception of subjects.

• Journal of Korea Water Resources Association
• /
• v.39 no.2 s.163
• /
• pp.161-178
• /
• 2006

Heathcote (1998) identified a systematic, seven-step approach to general watershed planning and management. It consists of 1) understanding watershed components and processes, 2) identifying and ranking problems to be solved, 3) setting clear and specific goals, 4) developing a list of management options, 5) eliminating infeasible options 6) testing the effectiveness of remaining feasible options, and 7) developing the final options. In this study the first five steps of that process were applied to the Anyangcheon watershed in Korea, which experiences streamflow depletion, frequent flood damages, and poor water quality typical of highly urbanized watersheds. This study employed four indices: Potential Flood Damage(PFD), Potential Streamflow Depletion(PSD), Potential Water Quality Deterioration(PWQD) and Watershed Evaluation Index(WEI) to identify and quantify problems within the watershed. WEI is the integration index of the others. Composite programming which is a method of multi-criteria decision making is applied for the calculation of PSD, PWQD and WEI (Step 2). The primary goal of the study is to secure instreamflow in the Anyangcheon during dry seasons. The second management goals of flood damage mitigation and water quality enhancement are also set (Step 3). Management options include not only structural measures that can alter the existing conditions, but also nonstructural measures that rely on changes in human behavior or management practices (Step 4). Certain management options which are not technically, economically, and environmentally feasible, are eliminated (Step S). Therefore, this study addresses a Pre-feasibility study, which established a master plan using Steps 1 through 5.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.6
• /
• pp.1726-1732
• /
• 2008

Injection molding is one of plastic forming technology which can easily mass-produce plastic parts with various and even complex shape. The technology has lots of difficulties in making a good part due to phase change of material, high applied pressure, and fast melt flow speed in the cavity. To overcome the problems, they had to make trial and error method until the CAE(Computer Aided Engineering) could be a tool for concurrent engineering. In this paper, we investigate the optimal design for a plastic DVD tray part by systematic approach of the commercial CAE program. In design, we should consider two objectives which are both dimensional stability and cost-down. The dimension of the part is crucial because the tray should carry a DVD correctly, but the part is too thin to injection-mold easily. In order to improve the moldability, the mold is designed in the form of stack mold which is a kind of 4 hot runner system. In first, we changed the stack-mold system with one hot-runner to cost down, and decided the optimal position of the gate. After that, we investigate the effect of both the layout of cooling channels and the cooling temperature on the shrinkage of the DVD tray. A optimal simulation approach, the gate design is 2Gate#3 and the layout is Case2 cooling line as the optimal temperature of $70^{\circ}C$. The Moldflow and PC+ABS are used for the CAE program and material respectively.