• Fire Science and Engineering
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• v.34 no.1
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• pp.79-88
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• 2020

This study analyzes the issue of the supply of force of fire in the high-rise buildings, and proposes an efficient method to do so. The results are as follows. First, in terms of Detect fire, it is necessary to shorten force of fire supply time by diversifying fire alarms such as alarms, vibrations, and voices from outside, clarification of fire occurrence points, and marking of fire. Second, with regard to communication signals, strengthening the installation target of wireless communication auxiliary facilities, supplementing the installation of repeaters, and constructing a multicommunications network were proposed. Third, in terms of Decide action, it is necessary to supply firefighter and firefighting equipment with the method of crossing of a river in adjacent buildings. Fourth, in terms of Respond to site, helicopters and emergency elevators are used to assist in the supply of firefighting equipment using drones. Easy-to-break glass windows and identification marks are required in every floor. Finally, in terms of applying fire suppressants, water can be supplied by means of a helicopter adjacent to the structure.

• Explosives and Blasting
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• v.37 no.4
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• pp.10-16
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• 2019

Information on overpressure, positive phase duration, and impulse are required to assess the effects of shock waves or pressure waves on the structure. In this study, the overpressure and positive phase duration were determined by applying the Multi-Energy Method, which is found to be effective in analyzing the explosion of vapor clouds. Based on the total heat of combustion estimated in the cyclohexane vapor cloud explosion in the Nypro Ltd(UK), overpressure and positive phase duration at the distance of 40, 80, 120, 160, 200, 240, 280, 320, 360(m) from the source of explosion were evaluated. Overpressure was shown to decrease exponentially and positive phase duration increased almost linearly with distance. A probit function was used to assess the probability of damages for the structures at each distance using the overpressure and impact obtained at the above mentioned distances. The Analyses of probability of damages have shown that there is a high probability of collapse at distances within 120m, major damage to structures within 240m, and minor damage and breakage of window panes of structures occur over the entire distances.

• Journal of Energy Engineering
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• v.1 no.1
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• pp.66-75
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• 1992

The performance of heat transfer through double pane window has been investigated using experimental and numerical methods. The range of the gap distance between glasses are 0.5-10 cm. The convection heat transfer plays the dominant role for the case of the wide gap distance together with the large Rayleigh number and thereby, reduces the enhanced thermal resistance due to the increased air gap, while the conduction heat transfer does the major role for the case of small gap distance. In order to enhance the thermal insulation of the double pane window, the heat transfer of triple pane window, which is constructed to put one more glass at the middle of the double pane, is investigated to check the reduction of the convection heat transfer together with the effect of the radiation shield due to the presence of the additional glass. Further, a spacer is installed at the middle height of the double pane, and the effect of which on the suppression of the convective heat transfer is analyzed carefully, using experimental and numerical methods. For the case of the spacer-installation, the amount of energy saving is considered about 10%, but the energy saving increases a lot to 30-50% for the case of triple pane window, due to the substantial radiation shield effect of the presence of the additional glass.

• Journal of the Institute of Convergence Signal Processing
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• v.20 no.4
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• pp.232-237
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• 2019

It has recently been combined with advanced technologies such as AR and VR, and its application range is expanding to various forms of smart signage. However, until now, digital signage service that reaches us is installed in many floating populations such as bus stops, elevators, and banks and is used in the form of providing news, weather, and advertisements. In addition, large companies, government offices, and outdoor advertising companies occupy the market. The use of such services in small and medium-sized businesses and small retail stores is costly and expensive to manage. Also, it is difficult to generalize the market because services and solutions are being deployed in the market in the form of top-down. Therefore, in this paper, we proposed a digital signage system for transmitting a remote video advertisement that uses a show window in front of the store as a beam project screen for small retail stores, and can remotely set and manage and update it in OSGi service platform.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.131-144
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• 2018

The purpose of this study is to empirically examine the unethical information sharing by information asymmetry. I will confirm the effect of ethical dilemma, unethical intention and behavior by the information asymmetry. A research method used the structural equations. The analysis showed causal relationship that ethical dilemma and unethical intention and behaviors by the information sharing. In particular, The ethical dilemma by position level showed different from the factor between dilemma and intention. As a result, the organization should manage differently ethical issue according to position level. The contribution in this study has expended an interpretation scope of broken windows theory from social science and explained a discriminative management of the ethical dilemma by position level from the practical view. A Future study should investigate an unethical behavior reduce by information security systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.1
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• pp.18-24
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• 2007

If an error occurs in a product that contains a source of vibration, an abnormal noise vibration will occur. Recently a system that has been modified from the previous method of noise detection-a method of appraising the quality of manufactured automobile part by using human ears-is being implemented in the industries of automobile parts. This new system distinguishes the product's vibration signals by measuring and analyzing the signals. Following the recent trend, it has been concluded that the appraisal process of Window Regulator Module needed an improvement. Thus, a vibration monitoring system using LabVIEW, which measures and analyzes vibration signals from a sector gear's connected part by using an accelerometer, has been developed. By analyzing the characteristics of vibration signals of both inferior and superior goods, now the quality of the product can be evaluated much more accurately.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4121-4124
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• 2015

Near infrared blocking function in energy saving window glass is required. The design, deposition and characteristics of optical thin films for reflection of near-infrared light were studied. The optical thin film is designed as laminated film structure with low refractive index film and high index film. Deposition experiments of $SiO_2$ and $TiO_2$ thin films with designed structure using the RF sputtering method were carried out. The characteristics of the thin film with deposition conditions were analyzed. High-refractive-index thin film of $TiO_2$/low refractive-index thin film of $SiO_2$ and high-refractive-index thin film of $TiO_2$ structure for reflection of near-infrared light was designed to be simulated. Results of simulation showed reflectance of 30% or more in the range from 930nm to 1682nm. Triple layer thin films fabricated with simulated results showed wavelength bands from 930nm to 1525nm for the reflectance of 33% or more.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.24-29
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• 2003

Numerical analysis was conducted to predict the damage of indoor gas explosion for the propagation of explosion flame. Indoor gas diffusion distribution due to gas leakage was obtained by diffusion equation that adopted initial conditions from reference. Enthalpy of each gas-mixture ratio and reduced mechanism was applied to calculate flame temperature, and laminar combustion velocities with the variant of each gas concentration from reference were applied to the gas mixture. Turbulent combustion velocity was modeled by coupling of turbulent energy and laminar combustion velocity in k-$\epsilon$ model. For the analysis of flame propagation cartesian and cylindrical coordinate were used to indoor position and flame propagation respectively. The study analyzes the cause of pressure rising with the variation of flame propagation by glass damage, and the result shows that indoor pressure rising with ignition position varies window dimension.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.290-296
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• 2019

Head-up displays for vehicles play an important role in displaying various information about the safety and convenience of driving on the windshield of the vehicle. In this study, ultra-precision machining was performed and evaluated as a method for machining a large-area aspheric free-form mirror that is applicable to augmented reality technology. Precision diamond cutting is highly accurate and suitable for the production of advanced parts with excellent surface integrity, low surface roughness, and low residual stress. By using an aspheric free-form mold, it is possible to improve the optical transfer function, reduce the distortion path, and realize a special image field curvature. To make such a mold, the diamond cutting method was used, and the result was evaluated using an aspherical shape-measuring machine. As a result, it was possible to the mold with shape accuracy (PV) below $1{\mu}m$ and surface roughness (Ra) below $0.02{\mu}m$.

• Journal of Korea Water Resources Association
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• v.50 no.1
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• pp.29-35
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• 2017

A vehicle rainfall sensor is made to control the operating speed of wipers depending on rainfall. Therefore this is the apparatus to determine the velocity phase of the wipers roughly based on the amount of rainfall. However, the technology which can judge the size of rainfall amount besides determining speed level of the wipers is developing according to the development of the function of rainfall sensor due to the development of technology. In this study, a rainfall measurement by using light scattering by precipitation particles was used. This measurement is to use light signal reflection from front glass and the bigger particle is the less detection of light by light scattering. The detection area of the rainfall sensor and detection channel were extended sizes to increase the accuracy of the rainfall. Also the W-S-R relational expression was developed by using a relationship between the specific precipitation (R) and the amount of sensor detection (S) when there is speed change of the wipers (W) and an indoor rainfall apparatus was used to convert sensing signal to rainfall. The signal system of vehicle rainfall sensor can be converted to the actual rainfall amount by using this formula and if this is provided to users then the vehicle observation network can produce higher-resolution than actual observation network can be produced.