• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.228-233
• /
• 2016

Auxetic material is a material which has negative Poisson's ratio(NPR). Auxetic material shows some distinctive property like high energy absorbing property and high shear modulus. Among these, synclastic curvature is very interesting characteristic. When synclastic-curvature-material bends, it changes its shape like dome, contrary to non-auxetic material which changes its shape like saddle(anticlastic). This distinctive property could make it easy to manufacture curved structure like nose cone or wing panel in aerospace engineering. In this study, we studied a quantitative analysis about synclastic curvature of re-entrant panel with finite element model. We suggested a concept 'Degree of Synclasticity(DOS)', which means a ratio of curvature of load-direction and load-orthogonal direction. We studied the variation of DOS with two factor, unit cell inner angle(${\theta}$) and load position angle(${\phi}$). DOS decreases as ${\theta}$ increases because the unit cell goes out of auxetic-shape. As ${\phi}$ varies, DOS changes in a large range. So proper optimization of ${\phi}$ would be needed for application.

• Journal of the Korea Furniture Society
• /
• v.19 no.4
• /
• pp.283-293
• /
• 2008

This study is intended to forecast changes in Ubiquitous technology-based residential environment since the digital revolution so as to suggest the direction of furniture design in the near future. Among Ubiquitous technologies, the intelligent digital technology applied to a residential environment is defined as "Smart Digital Technology." Ministry of Commerce, Industry and Energy named the residential environment where such technology is applied "Smart Home." Smart Home is strategically creating intelligent residential environment where interactivity is made between human, furniture and residential environment, based on home automation, home network and intelligent sensor technology. Smart furniture is based on strategic characteristics of smart home. Its convergence with IT equipments is being made. Largely, smart furniture has three characteristics as below: First, smart furniture provides users with information on home management, health management, education and fashion. not just functioning as storage space. Second, smart furniture that is a new lifestyle pattern will suggest a new aesthetic standard based on unsettled shapes and innovative structure. Finally, it gives convenience to users intelligently. Namely, smart furniture, "intelligent informative furniture", will be suggested as a new paradigm.

• Proceedings of the Korean Institute of Interior Design Conference
• /
• 2005.10a
• /
• pp.205-206
• /
• 2005

The plan for Shinseon Seolleongtang Restaurant in Kimpo has as its goal to create an environment strongly fused with the design of the modern city and the spirit of food culture craftsmanship, and it proceeded as follows. In order to carry out the goal of the plan, the direction of the design concept was set to be a harmonious blending of Ecology and Minimal. Also, for detailed plan direction, in the Minimal domain, conciseness, cleanliness, and high quality were established as the ultimate goals in order to create a spacious food and drink area in today's complicated and energy-draining society, and in the Ecology domain, ancient hieroglyphs representing the forms of natural objects were used that prayed for years of plentiful harvest and blessing, and colorfully expressed the events of the populace.

• Journal of Welding and Joining
• /
• v.7 no.4
• /
• pp.38-45
• /
• 1989

In this study, in order to evaluate the shape and the size of the plastic zone at the notch tip before stable crack growth, a newly developed technique for plastic strain measurement, that is, the recrystallization-etching technique was applied to observe the intense strain zone at the notch tip of weld HAZ. 1) The recrystallized specimens showed that the amount of the intense strain zone, more than 20% plastic zone, was quantitatively observed as the plane strain state during the growth of the plastic zone. 2) The behavior of plastic deformation at midsection are different for parent and weld HAZ. In addition, the micro crack initiation occurs at midsection, parent and weld HAZ when the crack opening displacement(COD) value is .delta.$_{t}$=0.4mm. 3) The plastic zone for parent proceeds in the forward direction at notch tip and for weld HAZ in the right and left direction at the notch tip. 4) The relation between plastic strain energy(Wp) and COD(.delta.$_{t}$) depended on yield stress, gradient and plastic strain size.ize.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.05a
• /
• pp.43-44
• /
• 2021

As drone technology advances, the cases of using drones in the construction industry are increasing rapidly. Research by the Ministry of Trade, Industry and Energy, has shown that drone use in the construction sector is expected to expand the fastest, and research has been carried out continuously to utilize drones in the construction industry. In this way, we will identify drone research trends in the construction industry as a basic data that will provide direction for future research. This paper collected papers for 10 years from 2011 to 2020 and keyword analysis through Gephi 0.9.2. This paper was classified by the study details of the paper with the upper keywords by year, through which it analyzed the changes in the direction of the study by field. The data in this paper is designed to contribute to the development of balanced drone utilization research, despite the limitations of 10-year statistics.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.2
• /
• pp.165-175
• /
• 2024

Hydrogen is being touted as one of the energy sources to combat the climate change crisis. However, hydrogen can leak into enclosed spaces, rise to the ceiling, accumulate, and cause fires and explosions if it encounters an ignition source. In particular, ships that transport hydrogen or use it as a fuel comprise multiple enclosed spaces. Therefore, the dif usion characteristics within these spaces must be understood to ensure the safe use of hydrogen. The purpose of this study is to experimentally determine the diffusion characteristics of helium, which has similar properties to hydrogen, in a closed space on board a ship, and to determine the change in the oxygen concentration along the leakage direction as the air change per hour(ACH) increases to 25, 30, 35, 40, and 45 through CFD simulation. The study, results revealed that the oxygen concentration reduction rate was 2% for leakage in the -z direction and 1% for leakage in the +x and +z directions, and the ventilation time was 15 min 30 s for leakage in the -z direction, 7 min for leakage in the +x direction, and 9 min for leakage in the +z direction, showing that differences existed in the oxygen concentration and ventilation time depending on the leakage direction. In addition, no significant difference was observed in the rate of oxygen concentration reduction and ventilation time in all leakage directions from the ACH of 35 and above in the experimental space. Therefore, because the oxygen concentration and ventilation time were not improved by increasing the ACH, 35 was noted as the optimal ACH in this experimental environment.

• Korean Chemical Engineering Research
• /
• v.53 no.5
• /
• pp.603-608
• /
• 2015

Alumina powder have been expanded its application in industry and required to control its morphology such as powder size and aspect ratio of single particle. It can be synthesized by molten - salt method which is possible to obtain various shapes of ceramic particles by controlling the growth direction because each crystal face has different growth rate. In this study, various combinations of salts such as NaCl, $Na_2SO_4$, $Na_3PO_4$ and their mixture were used for control the growth of plate like alumina particle from the initial stage of synthesis because salt having different ionic strength can control the growth direction of ceramic particle under its melting condition around $800{\sim}900^{\circ}C$, and growth behavior of plate-like alumina particle with different reaction conditions such as temperature and concentration on the crystal size and shape was studied.

• Journal of Energy Engineering
• /
• v.19 no.4
• /
• pp.251-257
• /
• 2010

Korea have a plan to enforce the Renewable Portfolio Standard(RPS) in 2012 for climate change action and effective use of energy but because of lack of renewable energy resources and limits of technology development, it will be hard to fullfill a target for RPS obligation in domestic power generation sector and woodchip biomass cofiring with coal combustion is the one of the alternative methods of the goal. Woodchip biomass cofiring with coal combustion is easy to approach technical design and has competitiveness of $CO_2$ & renewble energy certificate benefit and also has much lower generation cost than any other renewable energy resources. Because of that reason, woodchip biomass cofiring with coal combustion should be needed to fullfill the goal for RPS obligation in domestic power generation sector with midlong-term direction.

• KIEAE Journal
• /
• v.10 no.5
• /
• pp.63-69
• /
• 2010

Recently, by the increase of demand on Super High-rise mixed-use housing and it's advanced quality, the interest on it has been raised socially. In accordance with it, the matter of resident's health and energy efficiency has been controversial in terms of living in super high-rise housing. This study started from the idea that it is necessary to have an objective data which that has many residents in narrow space with high density. The purpose of this study are as follows; Firstly, with the quantitative data analysis on energy, it will confirm the objective information on the unclear negative idea of super high-rise mixed-use housing. Secondly, it will establish the fundamental data on the energy of super high-rise mixed-use housing by examining the characteristic of energy consumption of the complex which was built more than 5 years ago. There are 4 methods of this study. Firstly, it follows the steps of theoretical view, and defines concept to study on the characteristic of super high-rise mixed-use housing. Secondly, referring to the previous study, it provides better understanding on th stream of this research and the limit as well to guide the direction in terms of energy consumption. Thirdly, it evaluates the characteristic of monthly consumption by researching the use of electricity energy and heating energy of super high-rise mixed-use housing. The major conclusions of this study are as follows; Firstly, the heating use of apartment complex is same, which is not influenced by the type of the building. Secondly, the electricity use of super high-rise mixed-use housing is from 1,2 to 1.5 as high as the normal apartment.

• Korean Institute of Interior Design Journal
• /
• v.18 no.6
• /
• pp.221-228
• /
• 2009

Recently severity of ecological adaptation and climatic change due to global warming grows larger. According to the fourth report of IPCC in 2007, emission quantity of the earth greenhouse gas(GHGs) generated by activity of mankind increased with 80% since 1970. And it is forecasted that worldwide greenhouse gas will be increased with 25~90%(corresponding to $CO_2$) between 2000 and 2030. This increment of greenhouse gas($CO_2$) is expected to raise average temperature of the earth with the maximum $6.4^{\circ}C$, and sea surface with 59cm in 2090. Like this, destruction of environment by greenhouse gas is regarded as universal problem threatening the existence, not only the problem of one nation. Consequently, systematic correspondence to the global warming at the aspect of energy consumption is also needed in Korea. From the analysis result of 'Statistics of Energy Consumption' published by Green Korea in 2007, energy consumption increment of domestic universities was higher as many as 3.7 times than 22.5% of the whole energy consumption increment in our country. This says to be the direct example which shows that universities are huge sources of greenhouse gas emission. New constructing and enlarging buildings of each universities within campus are the most major reason for such a large increment of energy consumption in universities. The opinion that the possibility of causing energy waste and efficiency reduction is raised by increased buildings of universities has been propounded. That is, universities should make concrete goal and the plan for reducing emission of green house gas against climatic change, and should practice. Accordingly, there is the meaning that 2 aspects of environment-friendly design characteristics, that is application of energy utilizing technology, material usage of energy efficiency-side and environment-side, and introduction of natural element in the environmental aspect, were analyzed for facilities of university campus designed in environment-friendly point of view from initial stage of plan, and direction of environment-friendly design of university facilities in the future was groped in order to grasp environment-friendly design tendency of internal and external University facilities based on this analysis of this paper.