• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2003년도 추계학술대회
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• pp.407-412
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• 2003

Railroad line capacity is influenced by Quantitative and Qualitative factors which is applied by parameter to calculate it. But these parameters have been used experiential value without analyzing its reasonability or appropriate level. In this paper, we introduce the concept of robustness to Quantify parameter and evaluate robustness of it. For this purpose, we develop parameter evaluation simulator and present it. If this simulator is utilized, we can find the parameter having appropriate robustness and it will be applied to calculate more reasonable and systematic railroad line capacity.

• 한국조경학회지
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• 제20권3호
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• pp.93-102
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• 1992

This study was carried out to estimate the recreation carrying capacity of lawn areas in parks. Recreation carrying capacity in this study is composed of two parts, ecological carrying capacity. This part deals with the psychological carrying capacity, based on the perception of crowding level and recreation satisfaction of users. The survey was conducted at the lawn areas of Doturag World and Seorabul Plaza in Bomun Resort Complex in Kyungju. The major results are as follows: 1. As the result of regression of regression analysis between use density of lawn area and level of perceived crowding, the capacity was estimated as 60.0㎡ man. 2. As the result of regression analysis between use density of lawn areas and total recreation satisfaction, the capacity was estimated as 48.5㎡/man. 3. As the result of regression analysis between use density of lawn areas and satisfaction to use density, the capacity was estimated as 63.2㎡/man. 4. As a conclusion, the psychological carrying capacity was estimated as 60.0㎡/man. And this value is based on user's perception of crowding and recreation satisfaction level for each use densities.

• 상하수도학회지
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• 제29권1호
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• pp.65-75
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• 2015

In this study, cation and anion exchange process for performance evaluation was conducted. A pilot plant for the ultrpure water production was installed with the capacity of $25m^3/d$. The various production rate and regeneration of ion exchange rate were tested to investigate the design parameters. The test resulst was applied to calculate the operating costs. Changing the flow rate of the ion exchange capacity of the reproduction reviewed the cation exchange process as opposed to the design value is 120 to 164% efficiency, whereas both anion exchange process is 82 to 124% efficiency, respectively. This results can be applied for more large scale plant if the scale up parameters are consdiered. The ion exchange capacity of the application in accordance with the design value characteristic upon application equipment is expected to be needed. In this study, the performance of cation and anion exchange resin process was evaluated with pilot plant($25m^3/d$). The ion exchange capacity along with space velocity and regeneration volume was evaluated. In results, the operation results was compared with design parameters.

• Geomechanics and Engineering
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• 제23권1호
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• pp.15-30
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• 2020

The probabilistic bearing capacity of a strip footing placed on the edge of a purely cohesive reinforced soil slope is computed by combining lower bound finite element limit analysis technique with random field method and Monte Carlo simulation technique. To simulate actual field condition, anisotropic random field model of undrained soil shear strength is generated by using the Cholesky-Decomposition method. With the inclusion of a single layer of reinforcement, dimensionless bearing capacity factor, N always increases in both deterministic and probabilistic analysis. As the coefficient of variation of the undrained soil shear strength increases, the mean N value in both unreinforced and reinforced slopes reduces for particular values of correlation length in horizontal and vertical directions. For smaller correlation lengths, the mean N value of unreinforced and reinforced slopes is always lower than the deterministic solutions. However, with the increment in the correlation lengths, this difference reduces and at a higher correlation length, both the deterministic and probabilistic mean values become almost equal. Providing reinforcement under footing subjected to eccentric load is found to be an efficient solution. However, both the deterministic and probabilistic bearing capacity for unreinforced and reinforced slopes reduces with the consideration of loading eccentricity.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권3호
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• pp.179-184
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• 1999

In the past ten years, $LiMn_2O_4$-based spinels have been extensively studied as positive electrode materials for lithium-ion batteries. To improve the cycle performance of spinel $LiMn_2O_4$ as the cathode of 4V class lithium secondary batteries, spinel phases $LiMn_2O_4$ were prepared at various temperatures ranging form 600-900$^{\cire}C$ in air. The results showed that charge.dischare capacity of $LiMn_2O_4$ varied at 1st temperature from $200^{\circ}C to 600^{\circ}C$ increase with increasing temperature. $LiMn_2O_4$ synthesized at 2nd temperature $750^{\circ}C$excellent charge.discharge capacity, efficiency and cyclability compared to the samplesynthesized different temperatures. The value of lst charge.discharge capacity was 121mAh/g, 118mAh/g, Also, the efficiency value was about 97%.

• KIEAE Journal
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• 제10권5호
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• pp.151-157
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• 2010

This study is connected with evaluation of the progressive collapse resisting capacity for sustainable RC super tall building design. As the progressive collapse is not considered in current design codes in Korea, differences between linear static and dynamic analysis based on the GSA guidelines was analyzed for better evaluation, and the analysis model of flat plate system was determined. Finally, the progressive collapse resisting capacity was evaluated for structural system of super tall building. According to this study, the results by linear dynamic analysis were underestimated than the results by linear static analysis. Thus, the dynamic coefficient value of 2 provides conservative approach. The Effective Beam Width's model, currently used in field, is useful for the analysis about lateral force, but this model does not consider the effect of load redistribution by the slab. Hence, finite element analysis considering slab element will be needed for progressive collapse resisting capacity of the flat plate system. Finally, analysis model of 80-story building designed based on KBC(Korea Building Code) shows the weakness against progressive collapse because the DCR value is over 2. Thus, the countermeasure for alternative loading path such as installment of spandrel beam and reinforcements around slab is required to prevent the progressive collapse.

• Structural Engineering and Mechanics
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• 제82권1호
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• pp.81-92
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• 2022

Ultra-high performance fiber reinforced concrete (UHPFRC) is a composite building material with high ductility, fatigue resistance, fracture toughness, durability, and energy absorption capacity. The aim of this study is to develop a nonlinear finite element model that can simulate the response of the UHPFRC beam exposed to impact loads. A nonlinear finite element model was developed in ABAQUS to simulate the real response of UHPFRC beams. The numerical results showed that the model was highly successful to capture the experimental results of selected beams from the literature. A parametric study was carried out to investigate the effects of reinforcement ratio and impact velocity on the response of the UHPFRC beam in terms of midpoint displacement, impact load value, and residual load-carrying capacity. In the parametric study, the nonlinear analysis was performed in two steps for 12 different finite element models. In the first step, dynamic analysis was performed to monitor the response of the UHPFRC beam under impact loads. In the second step, static analysis was conducted to determine the residual load-carrying capacity of the beams. The parametric study has shown that the reinforcement ratio and the impact velocity affect maximum and residual displacement value substantially.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권6호
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• pp.514-518
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• 2004

Many methods are used in the measurement of antioxidative capacity. These meth­ods require very complex procedures and pretreatment. Our suggestions for research will be simple and accurate methods for obtaining many kinds of samples, especially colored samples such as natural product extracts for measuring antioxidative capacities. For oxidation-reduction potential (ORP) system value, we examined the relationships between the ORP-pH system and the ORAC, FRAP methods. To evaluate ORP System value, we calculated the absolute slope/intercept from the linear regression of each standard material at different concentrations and ORP-pH system, and compared the correlations with ORAC and FRAP values.

• 태양에너지
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• 제12권3호
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• pp.126-136
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• 1992

In this paper an EGD generator of small capacity with the operating gases of $O_2,\;N_2$ and air is made and the electric characteristics in relation to energy conversion range length, corona current and gas pressure are investigated. The results are as follows: 1. There is a critical value in conversion range length for maximum open voltage and the critical value increases with fluid velocity. 2. The open voltage increases approximately linearly with corona current. 3. There is a critical value in the gas pressure for maximum open voltage and this pressure of gas decreases with fluid velocity in constant conversion range length.

• 한국항만학회지
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• 제10권2호
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• pp.69-90
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• 1996

This study is related to save the bearing capacity from using Meyerhof formula namely, static mechanics formula with the S.P.T(N value) of the soft ground and is to choose the soft ground improvement method by the using of total load for the proper method of the pile foundation and then to design the most suitable pile foundation to fit the actual circumstance. The purpose of this study is calculating the diameter of the pile foundation by static mechanics formula and introducing the optimum design condition from the result of the bearing capacity for using N value of the S.P.T obtained from the deep soft ground about the piles such as P.H.C pile, pipe and cast-in-place pile of big diameter, etc. As above-mentioned, it is considered that the use of P.H.C pile or pipe pile is advisable on the synthetical investigation and that the selection of cast-in-place pile method is desirable in terms of the constructive safety and durability.