• Structural Engineering and Mechanics
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• v.29 no.2
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• pp.187-201
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• 2008

Earthquake induced hysteretic energy demand for a structure can be used as a limiting value of a certain performance level in seismic design of structures. In cases where it is larger than the hysteretic energy dissipation capacity of the structure, failure will occur. To be able to select the limiting value of hysteretic energy for a particular earthquake hazard level, it is required to define the variation of hysteretic energy in terms of probabilistic terms. This study focuses on the probabilistic evaluation of earthquake induced worst failure probability and approximate confidence intervals for inelastic single-degree-of-freedom (SDOF) systems with a typical steel moment connection based on hysteretic energy. For this purpose, hysteretic energy demand is predicted for a set of SDOF systems subject to an ensemble of moderate and severe EQGMs, while the hysteretic energy dissipation capacity is evaluated through the previously published cyclic test data on full-scale steel beam-to-column connections. The failure probability corresponding to the worst possible case is determined based on the hysteretic energy demand and dissipation capacity. The results show that as the capacity to demand ratio increases, the failure probability decreases dramatically. If this ratio is too small, then the failure is inevitable.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2008.05a
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• pp.159-160
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• 2008

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.05a
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• pp.223-224
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• 2017

• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.130-135
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• 2000

We have analyzed characteristics for the structure of $Al_{0.25}/Ga_{0.75}/As/In_{0.15}/Ga_{0.85}$/AS/GaAS pseudomorphic high electron mobility transistor (PHEMT) by photoluminescence (PL) and photoreflectance (PR) measurements. By the PL measurement at 10 K, we observed el-hl transition peak at 1.322 eV and e2-hl transition peak at 1.397 eV in the InGaAs quantum well. We calculated value of 23 meV, the difference between the first energy level and the second energy level of a valence band by dependence of temperatures. Also, (e2-h2) transition signal was observed at 300 K by PR measurement. From the PR measurement, we recognized that the transition was dominated the second energy level of conduction band than the first energy level of conduction band due to band filling. The other hand, PL signal of the first energy level of conduction band was dominated because of the electron screening effect.

• Journal of the Korean Home Economics Association
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• v.44 no.8
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• pp.79-87
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• 2006

The purpose of this study was to estimate the minimum monthly food cost for the low income population. The food consumption data of 9,311 individuals from the 2001 Korean National Health and Nutrition Survey was used. The monthly food cost was calculated using the Consumer Food Price Database for the year 2001 provided by the Public Health Nutrition Laboratory, Seoul National University. The low income population (n = 1,310) was characterized as older age, lower income, smaller family size, lower education level, and lower energy intake as compared with the total population (n = 8,001). The estimated food cost showed that men in the low income population needed 15% more money for purchasing food to maintain the energy intake level at the average energy intake level of men in the total population. It was also estimated that women in the low income population needed 9% more money for purchasing food to maintain the energy intake level at the average energy intake level of women in the total population. There were differences in monthly food costs depending on the sex and age, and family size. The results of this study could be used as basic information to establish minimum food cost for the low income population in Korea.

• Structural Engineering and Mechanics
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• v.86 no.6
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• pp.739-750
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• 2023

This study examines the two-level behavior of the toggle brace damper within a steel frame having a yielding pipe damper and rotational friction damper. The proposed system has two kinds of fuse for energy dissipation in two stages. In this mechanism, rotational friction damper rather than hinged connection is used in toggle brace system, connected to a pipe damper with a limited gap. In order to create a gap, bolted connection with the slotted hole is used, such that first a specific movement of the rotational friction damper solely is engaged but with an increase in movement, the yielding damper is also involved. The performance of the system is such that at the beginning of loading the rotational friction damper, as the first fuse, absorbs energy and with increasing the input load and further movement of the frame, yielding damper as the second fuse, along with rotational friction damper would dissipate the input energy. The models created by ABAQUS are subjected to cyclic and seismic loading. Considering the results obtained, the flexibility of the hybrid two-level system is more comparable to the conventional toggle brace damper. Moreover, this system sustains longer lateral displacements. The energy dissipation of these two systems is modeled in multi-story frames in SAP2000 software and their performance is analyzed using time-history analysis. According to the results, permanent relocations of the roof in the two-level system, in comparison with toggle brace damper system in 2, 5, and 8-story building frames, in average, decrease by 15, 55, and 37% respectively. This amount in a 5-story building frame under the earthquakes with one-third scale decreases by 64%.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.129-138
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• 1992

The effects of dietary levels of lysine and energy on growth performance, the content of DNA, RNA and protein in liver, thigh muscle composition and nutrient utilization in broiler chicks were investigated in an experiment involvies with 2 levels of dietary energy : 3,200 (2900) 2,900 (2700) kcal ME/kg) and 6 levels of lysine : 0.6(0.5), 0.8(0.7), 1.0(0.9), 1.2(1.1), 1.4(1.3), and 1.6(1.5)% was carried out. A total number of 384 male broiler chicks was used for a period of 7 weeks. Body weight gain of 1.0(0.9)% lysine level group was significantly (p < 0.01) higher than that of any other groups. Interaction between lysine and energy in the feed intake was observed (p < 0.05). Present data indicate that the content of DNA in liver tissues was significantly (p < 0.05) different by the levels of lysine, namely, 1.0(0.9)% or 1.2(1.1)% lysine level groups showed higher content than other groups (p < 0.01). Dietary levels of 1.2(1.1)% or 1.6(1.5)% lysine groups showed the highest protein content in thigh muscle tissues than that of any other groups (p < 0.05). Interaction between energy and lysine in the content of protein of thigh muscle tissues was shown (p < 0.01). The level of 0.6% lysine group showed the highest fat content in thigh muscle tissues than any other groups. Interaction between lysine and energy in the content of crude ash and crude fat of thigh muscle tissues was observed (p < 0.01). Apparent amino acid availability of arginine, glycine and threonine (p < 0.01), phenylalanine (p < 0.05) were significantly affected by the levels of lysine and interaction between lysine and energy was found only in arginine (p < 0.01).

• The Journal of the Convergence on Culture Technology
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• v.3 no.1
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• pp.43-48
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• 2017

We are confirmed to the variation of the transfer condition and the functional penetration by the permitted conversion energy on the skin. The given conversion energy is consist of the flow level of penetration control and go to the processing transfer in the skin that is to create the modeling for algorithm. The energy level of control processing was achieved effectively modeling system that was the composition of auto and local control level in the epidermis-dermis layer. Their penetration pulse control system was consisted of conversion energy with reference of fixing situation and recreation of designed apparatus for the energy control function that was converted to capacity by the size, form and combination. Also, the system was shown accurately distribution of conversion at the depth of skin correction. Therefore, conversion modeling was established effectively to separate the division parts for conversion system. We will be possible to progress the improvement effectiveness of the skin and to consist of the continuous penetration control system for functional energy on the skin.

• Journal of IKEEE
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• v.26 no.1
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• pp.1-9
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• 2022

In order to secure the reliability of the power system and to increase the penetration level of distributed energy resources (DERs), requirements such as IEEE 1547 have been revised to strengthen the grid connection standards for DER. This paper proposes a control scheme for smart inverter functions based on IEEE 1547-2018 that satisfy these standards, and introduces a power HILS-based test platform built for verification of smart inverter. Among the smart inverter functions, Volt-var and Frequency-watt allow the curve to be set from the upper level to comply with the interoperability and operation time of enable signals for each function are controlled by references from the upper level. According to the requirement, Volt-var and Frequency-watt are performed via power HILS platform and verified through the measurement results that all of the specified type tests were satisfied.

• Geotechnical Engineering
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• v.8 no.1
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• pp.59-66
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• 1992

The SPT If value has been known to be influenced by various factors, among which the actually delivered energy level of the falling ram has the most significant effect. If N values of different energy levels are to be applied in the general analysis which is based on N values of standard energy levee the safety of the foundation might be in danger or the design might be overestimated. In this study the actual falling velocity of the ram has been measured so that the energy level could be estimated. The results Indicated that the energy level should be considered in the analysis or the design in this country, since the measured values are different from the internationally accepted scandard value, N60