• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.473-480
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• 2012

In order to develop an effecive seismic strengthening metghod for existing concrete structure, structural tests of aramid FRP reinforced RC columns are performed. The test variables were strengthening methods of aramid sheet and strip. The test results were evaluated by comparing strength and energy dissipation capacities of non-reinforced and reinforced specimens. The test result comparison showed that aramid sheet reinforcement on RC column was evaluated as the most efficient way to increase strength and energy dissipation capacity.

• Journal of Ocean Engineering and Technology
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• v.30 no.2
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• pp.100-108
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• 2016

A high-pressure ball valve was developed, and both the structural strength and sealing performance were assessed based on a nonlinear finite element analysis. Different parts were modeled with solid elements and assembled, taking into account both contact and sliding effects. Three different loading scenarios were analyzed, including a high-pressure closure test and fire and shell test conditions. The structural safety of each part was checked under each loading condition, and the sealing performance was also investigated to validate the performance of the valve.

• CELLMED
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• v.10 no.2
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• pp.10.1-10.5
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• 2020

Ayurveda is the science of life. It guides about the protection of health of the healthy and alleviation of ailments of diseased person. In Ayurveda Upavasa (fasting) is one among all Daivavyapashraya (spiritual) therapies and one among ten Langhana (that which produces lightness of the body) therapies. It is also stated in Ayurveda that fasting increases digestive fire and causes digestion of Ama-dosha (metabolic toxins). On religious grounds, Upavasa is a way to get closer to the almighty. Scientists have found fasting activates autophagy. Yoshinori Ohsumi, a Japanese cell biologist won the Nobel Prize in Medicine in 2016 for his research on how cell recycle and renew their content, a process called autophagy. Many published studies indicate positive effects of fasting on neuroprotection and longevity.

• International Journal of Safety
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• v.1 no.1
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• pp.18-23
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• 2002

A mixture fraction formulation is used to numerically simulate the structure of diluted axisymmetric methane-air nonpremixed counterflow flames. The effects of global strain rate and gravity wert! investigated and results were compared. Fuel of a mixture of 20% methane and 80% nitrogen by volume and oxidizer of pure air at low and moderate global strain rates $a_g= 20, 40, 80 s^{-1}$ in normal and zero gravity were computed. It is shown that the numerical method is capable of predicting the structure of counterflow flames in normal and microgravity environments at low and moderate global strain rates.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1299_1300
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• 2009

We show results that examine about electrical properties of XLPE insulated 6.6kV cable termination by mechanical damage. The cable used to produce the cable termination is 6/10kV tray XLPE fire retardant electric cable (6/10kV TFR-CV $35SQMM{\times}1C$) which is domestically made. We apply force to XLPE insulator and made mechanical defect using knife. Defected samples go through the withstand voltage test according to the IEEE std. 48 test regulations and lighting impulse (hereunder, IMP) withstand voltage test regulations. Then the effects of the scars shown during the construction process on electric accidents at the end part are analyzed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.4
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• pp.580-584
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• 2012

The insulating oils perform a cooling and insulation action in electric power transformer. The mineral oil has immanent fire dangerousness and environmental contamination problem. Vegetable insulating oil has higher ignition point, flash point and more excellent biodegradability than conventional mineral oil. In a real oil-filled transformers, some of the power is dissipated in the form of heat. And transformer require the heat to be removed from the winding and insulator by forced convection of the insulating oil. The flow electrification occurs when insulating oil was forced to be circulated. In this paper, influence of temperature, velocity of flow, and insulating pipe and diameter on streaming electrification of vegetable insulating oil was investigated using forced circulation apparatus. Temperature effects were most significant, and it showed a peak in the temperature $30^{\circ}C$ to $35^{\circ}C$ at insulating and copper pipe. The change of flow electrification according to area variety could be checked by change of diameter.

• International Journal of Safety
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• v.2 no.1
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• pp.7-11
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• 2003

Structure of the counterflow nonpremixed flames were investigated by using Fire Dynamics Simulator(FDS) and OPPDIF to evaluate FDS for simulations of the diffusion flame. FDS, employed a mixture fraction formulation, were applied to the diluted axisymmetric methane-air nonpremixed counterflow flames. Fuel concentration in the mixture of methane and nitrogen was considered as a numerical parameter in the range from 20% to 100% increasing by 10% by volume at the global strain rates of $a_g = 20S^{-l} and 80S^{-1}$ respectively. In all the computations, the gravity was set to zero since OPPDIF is not able to compute the buoyancy effects. It was shown by the axisymmetric simulation of the flames with FDS that increasing fuel concentration increases the flame thickness and decreases the flame radius. The centerline temperature and axial velocity, and the peek flame temperature showed good agreement between the both methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.1
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• pp.88-93
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• 2005

In this study, the operational characteristics on heating performance and energy consumption for intermittent hot water heating system in apartment buildings were research by simulation. The effects of apartment inlet hot water temperature and operation time per day on energy consumption and indoor thermal environment are investigated. The strategy of energy saving and thermal environment improvement is suggested in comparison with the existing ones.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.468-475
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• 2001

It can be seen through the previous earthquake damages that indirect damages such as those by fire are much greater rather than direct (firsthand) damage by earthquakes. Recently, gas is used very popularly all over the country but no measures have been taken against hazards (or dangers), for instance, such as fires caused by leaking gas pipes when earthquakes occur. Earthquake-Actuated Automatic Gas Shutoff Devices (Shutoff Device) are used to prevent such disaster in other countries. ChungJung Engineering. Co. is making a sample of a Shutoff Device for the first time in Korea. In this study, a derivation of mathermatical model and the important effects of various variables on the shutoff device are mentioned.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.477-478
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• 2009

The objective of this study is to increase the insight of the mechanical behaviour of high-strength concrete prepared with fiber reinforcement after exposure to elevated temperatures. In particular, the result of the effects of contents of polypropylene fiber and level of preload on the residual compressive strength, load bearing and stress-strain curve of concrete are discussed