• Journal of the Korean Solar Energy Society
• /
• v.36 no.2
• /
• pp.53-63
• /
• 2016

Building Integrated Photovoltaic (BIPV) is one of the best ways to generate electric power using the solar energy, which is clean and inexhaustible energy resources. The most of BIPV modules have the form of GtoG (Glass to Glass) photovoltaic in building applications. Degradation leading to failure in photovoltaic modules is very important factor in BIPV modules. This paper analyzed the performance of various BIPV modules through outdoor exposure tests. Performance of three BIPV modules(c-Si type, a-Si type and DSSC type) with three installation angles influenced by sun light, outdoor temperature, and wind velocity was monitored and analyzed. As a result, c-Si type BIPV module outperforms other BIPV modules(a-Si type). In terms of power efficiency of the module, the installed angle of $45^{\circ}$ is better than others(90 degree, 0 degree). In addition, more realistic data of various BIPV system performance could be available through the field test and integrated building test. In this study, relationship of the BIPV system is identified module's installation angle, power generation, architectural performance, etc.

• Journal for History of Mathematics
• /
• v.20 no.3
• /
• pp.147-166
• /
• 2007

This study is about the law of cosines. It dealt with its historical origin and the developmental process of the age of Greece, Islam and Modern age. Especially, we tried to find out how the extension of the law of cosines for spherical triangles and tetrahedron from the law of cosines for plane was done. On the basis of this analysis, we investigated how the law of cosines was generated and proved it through the logical demonstration and mathematical induction. This made us find out the mathematical meaning of mathematical concepts.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2003.11a
• /
• pp.411-420
• /
• 2003

An advanced spent fuel conditioning process (ACP) is developing for the safe and effective management of spent fuels which arising from the domestic nuclear power plants. And its demonstration facility is under design. This facility will be prepared by modifying IMEF's reserve hot cell facility which reserved for future usage by considering the characteristics of ACP. This study presents a basic structural architecture design and analysis results of ACP hot cell including modification of the IMEF. The results of this study will be used for the detail design of ACP demonstration facility, and utilized as basic data for the licensing of the ACP facility.

• Korean Journal of Applied Biomechanics
• /
• v.23 no.1
• /
• pp.19-24
• /
• 2013

The aim of the study was a quantitative analysis of elite athlete's $540^{\circ}$ Dwihuryeochagi and effects of ground movements to the jumping height and kicking velocity. Eleven elite players(Taekwondo demonstration team) participated in this study. In order to get the kinetic and kinematic variables, ten Vicon cameras and a force plate were used. Foot segment velocity(FSV), vertical ground reaction force(GRF), impulse, ground time(GT) in phase 1, trunk angular velocity(TAV), vertical center of gravity(COG), flight time(FT) in phase 2 and kicking leg segment velocity(KSV) in phase 3 were measured and analyzed. Results indicated that there were similar patterns of variables among phases between subjects. Non-significant correlation(r=.145) between flight time(FT) and impulse was found. Also non-significant correlation(r=.119) between center of gravity(COG) and impulse was found. In conclusions, there were similar strategies in phase 1, phase 2, and phase 3 between subjects.

• Journal of Family Resource Management and Policy Review
• /
• v.11 no.2
• /
• pp.67-83
• /
• 2007

The purpose of this study was to evaluate the childcare support demonstration services and direct policy. The participants for the study were three childcare (IDOLBOMI), three parents who were provided with IDOLBOMI, two practitioners, and three professors related to IDOLBOMI. The data was collected by interview and a phone survey and analyzed qualitatively. The results and several suggestions were follows: First, IDOLBOMI loved to take care of children, felt proud of the job, and thought the work was worthy. The result can help future IDOLBOMI when they are recruited and trained; Second, IDOLBOMI wanted income security at least, which means that the basic activity fee for the IDOLBOMI should be compensated by government; Third, most of the parents who experienced the service were generally satisfied with that, but they wanted the quality of nutrition, hygiene and the quality of play to be developed for children. Therefore, the management of the center and maintenance of education are needed constantly for the IDOLBOMI system; Fourth, the parents who needed the service thought the cost of IDOLBOMI was expensive. Expenditure support should be sought for the parents; Finally, the group of professionals had difficulty in securing the quality of childcare support services. For the future, it is necessary to increase the educational budget, manpower resources, and PR budget for IDOLBOMI.

• Korean Journal of Artificial Intelligence
• /
• v.9 no.2
• /
• pp.15-21
• /
• 2021

This paper conducted a feasibility study by applying an Internet of Things and Artificial intelligence-based management system for the elderly living alone in an aging society. The number of single-person families over the age of 50 is expected to increase, and problems such as health, safety, and loneliness may occur due to aging. Therefore, by establishing an IoT-based care system for the elderly living alone, a stable service was developed through securing a rapid response system for the elderly living alone and automatically reporting 119. The participants of the demonstration test were subjects under the jurisdiction of the "Seongnam Senior Complex," and the data collection rate between the IoT sensor and the emergency safety gateway was high. During the demonstration period, as a result of evaluating the satisfaction of the IoT-based care system for the elderly living alone, 90 points were achieved. We are currently in the COVID-19 situation. Therefore, the number of elderly living alone is continuously increasing, and the number of people who cannot benefit from care services will continue to occur. Also, even if the COVID-19 situation is over, the epidemic will happen again. So the care system is essential. The elderly care system developed in this way will provide safety management services based on artificial intelligence-based activity pattern analysis, improving the quality of in-house safety services.

• Nuclear Engineering and Technology
• /
• v.51 no.7
• /
• pp.1842-1852
• /
• 2019

The AP1000 reactor coolant pump is a vertical shielded-mixed flow pump, is the most important coolant power supply and energy exchange equipment in nuclear reactor primary circuit system, whose steadystate and transient performance affect the safety of the whole nuclear island. Moreover, safety demonstration of reactor coolant pump is the most important step to judge whether it can be practiced, among which software simulation is the first step of theoretical verification. This paper mainly introduces the fluid-solid coupling simulation method applied to reactor coolant pump, studying the feasibility of simulation results based on workbench fluid-solid coupling technology. The study found that: for the unsteady calculations of the pure liquid media, the average head of the reactor coolant pump with bidirectional fluid-solid coupling decreases to a certain extent. And the coupling result is closer to the real experimental value. The large stress and deformation of rotor under different flow conditions are mainly distributed on impeller and idler, and the stress concentration mainly occurs at the junction of front cover plate and blade outlet. Among the factors that affect the dynamic stress change of rotor, the pressure load takes a dominant position.

• Journal of Korean Elementary Science Education
• /
• v.43 no.1
• /
• pp.64-80
• /
• 2024

This study aims to investigate the characteristics of verbal interaction in science class demonstrations conducted by elementary school pre-service teachers. Specifically, the study intends to examine the use of elements of verbal interaction and the progression of these interactions. Additionally, the study intends to analyze the perception of pre-service teachers about effective questioning and feedback and to determine the correlation between the proportions of the types of questioning and feedback positively perceived by the pre-service teachers and of the types of questioning and feedback used during class demonstration. Toward this end, the study analyzed the science class demonstration videos and class evaluation sheets submitted by 38 fourth-year students at the S University of Education. The results are as follows. First, pre-service elementary school teachers generally use close-ended questions during science class demonstrations. Moreover, they predicted that students would primarily provide the correct responses and would not engage in extended interaction by providing immediate feedback for the responses of the majority of the students. Second, pre-service elementary school teachers perceived the utilization of close-ended questions and immediate feedback in science class demonstrations more favorably than they did that of open-ended questions and delayed feedback. The study observed a weak positive correlation between the positive perception of specific types of questions and feedback and the use of such types in class demonstration. The results demonstrated that pre-service elementary school pre-service teachers tend to engage in fragmented verbal interactions during science class demonstrations. They primarily use close-ended questions and immediate feedback. This tendency is seemingly related to their perception of questions and feedback. Therefore, education institutions for training pre-service teachers need to provide opportunities for reflecting on verbal interactions, which tend to involve close-ended questions and immediate feedback. Lastly, assessing the perception of pre-service teachers of questions and feedback is also necessary.

• The Journal of Engineering Geology
• /
• v.28 no.2
• /
• pp.193-206
• /
• 2018

In this study, as part of the "Small-scale $CO_2$ Injection-Demonstration Project in Offshore Pohang Basin", we performed drilling and completion of a $CO_2$ injection well from the offshore platform installed in the Yeongil Bay, Pohang city, Gyeongsang buk-do. The drilling of injection well was carried out from an offshore platform installing on the sediment formations of the Pohang Basin. Drilling diameters were reduced by stages, depending on the formation pressure and groundwater pressure along a depth and the casing installation and cement grouting in drilled hole were performed at each stage. The injection well was drilled to a final depth of 816.5 m with a hole diameter of 4 7/8 inches (${\Phi}124mm$) and the perforated casing for an injection section was installed in a depth of 746.5~816.5 m. Injection tubing, packer, and christmas tree were installed for the completion of an injection well for $CO_2$. The validation project of the $CO_2$ injection was accomplished successfully by drilling the injection well and installing the injection facilities, and through the suitable $CO_2$ injection process. The current injection facility is a facility for small-scale injection demonstration of 100 tons. In the case of large-scale demonstration facility test of a capacity of 10,000 tons, research is underway through the upgrading of the injection facilities.

• Land and Housing Review
• /
• v.12 no.2
• /
• pp.1-12
• /
• 2021

The purpose of this study is to provide implications for the demonstration and the spread of smart cities. For this, the European Lighthouse project, a well-known smart city initiative, is analyzed. This article investigates agendas, applied solutions, stakeholders and cooperation, and expansion strategies in the 18 Lighthouse projects implemented by the EIP-SCC Smart City Demonstration Project. Four implications are discussed for Korean smart city projects. First, in promoting smart cities, clear philosophies and principles should be established in response to global issues such as climate change. Second, smart cities should be understood as the approaches for problem-solving rather than simply applying advanced technology. Third, a business system should be established in a way to meet the needs of the actors participating in the smart city demonstration project. Finally, an evaluation framework should be established to verify the performance of the project. High-performing best-practice projects should be supported by articulating their standards for their lessons to be spread into other cities. The implications presented here can contribute to developing smart city models along with follow-up studies.