• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2166-2171
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• 2023

In the present study, six silicone rubber doped by tellurium borate oxides were fabricated using the casting method. The densities of the fabricated silicon rubber-doped by tellurium borate oxides samples were measured using the Archimedes Method. Moreover, the linear attenuation coefficient of silicone rubber doped tellurium borate oxides samples was evaluated experimentally using the hyper pure germanium, and the recorded linear attenuation coefficient values were affirmed using the theoretical Phy-X program. The experimental measurements were performed using the narrow beam transmission method with radioactive isotopes Am-241, Cs-137, and Co-60 with energies of 59, 661, 1173, and 1332 keV. The linear attenuation coefficient values showed an enhancement by 4.73 times, 1.20 time, 1.17, time, and 1.17 time, respectively at gamma photon energies of 59, 661, 1173, and 1332 keV, when the TeO₂ concentration increased in the fabricated composites from 0 to 50 wt%. The enhancement of the linear attenuation coefficient values has a positive effect on the transmission rate values where the half-value thickness and transmission rate were decreased accompanied by an increase in the RPE.

• Structural Engineering and Mechanics
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• v.75 no.1
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• pp.33-47
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• 2020

In this paper the dynamic behavior of an isolated building subjected to idealized near-fault pulses is investigated. The building is represented with a simple 2-DOF model. Both linear and non-linear behavior of the isolation system is considered. Using dimensional analysis, in conjunction with closed form mathematical idealized pulses, appropriate dimensionless parameters are defined and self-similar curves are plotted on dimensionless graphs, based on which various conclusions are reached. In the linear case, the role of viscous damping is examined in detail and the existence of an optimum value of damping along with its significant variation with the number of half-cycles is shown. In the nonlinear case, where the behavior of the building depends on the amplitude of the excitation, the benefits of dimensional analysis are evident since the influence of the dimensionless 𝚷-terms is easily examined. Special consideration is given to the normalized strength of the non-linear isolation system that appears to play a complex role which greatly affects the response of the 2-DOF. In the last part of the paper, a comparison of the responses to idealized pulses between a linear fixed-base SDOF and the respective isolated 2-DOF with both linear and non-linear damping is conducted and it is shown that, under certain values of the superstructure and isolation system characteristics, the use of an isolation system can amplify both the normalized acceleration and displacement of the superstructure.

• Journal of the Korea Computer Industry Society
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• v.10 no.4
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• pp.167-176
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• 2009

In this paper, we propose an improved SHACAL-1 of the same encryption and decryption with a simple symmetric layer. SHACAL-1 has 4 rounds, and each round has 20 steps. Decryption is becoming inverse function of encryption, In this paper, we proposed SHACAL-1 are composed of the first half, symmetry layer and the last half. The first half with SHACAL-1 encryption algorithm 1 round does with 10 steps and composes of 4 round. The last half identically with SHACAL-1 decryption algorithm, has a structure. On the center inserts a symmetry layer, encryption and decryption algorithm identically, composes. In the experiments, the proposed SHACAL-1 algorithm showed similar execution time to that of the SHACAL-1. Thanks to the symmetric layer, the proposed algorithm makes it difficult for the attacks which take advantages of high probability path such as the linear cryptanalysis, differential cryptanalysis. The proposed algorithm can be applicable to the other block cipher algorithms which have different encryption and decryption and useful for designing a new block cipher algorithm.

• Journal of the Korea Fashion and Costume Design Association
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• v.14 no.2
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• pp.11-21
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• 2012

The purpose of this study is to understand of future image in fashion for 20C, to suggest a guideline's role in the development on fashion designs study. The methods of this study are used academic literatures as well as practical study. Futuristic image in fashion is to introduce about the future period, as fashion goes ahead times. Trends and formative characteristics of future image in 20C fashion are summarized as follows. First, futuristic images in fashion for 20C had emerged strongly futurism, space look, kinetic look, glitter look, techno look, cyber look. Second, perspectives on response for future society's changes are summarized as follows. Attitude of futuristic images of fashion, futurism, space look, kinetic look and glitter look, had been favorable about future society's changes until 1980. In 1990, techno look had been defensive and cyber look had been aggressive about future society's changes. Third, formative characteristics of future image in 20C fashion are studied shape, material, color, pattern. Shape was preferred linear and geometric form in the first half of the 20C, but body conscious type had appeared often in the second half of 20C. Material maintained the luster or the metal touch. Color was based image of colorless and preferred the gold, silver or color feels like metal. Pattern was preferred clarity with geometric type in the first half of the 20C. On the other hand in the second half of 20C pattern of future image was dominated by vague and abstract chaotic type.

• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.673-683
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• 2016

This paper analyzes the accuracy of the methods used in calibrating the thermal power of Nigeria Research Reactor-1 (NIRR-1), a low-power miniature neutron source reactor located at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. The calibration was performed at three different power levels: low power (3.6 kW), half power (15 kW), and full power (30 kW). Two methods were used in the calibration, namely, slope and heat balance methods. The thermal power obtained by the heat balance method at low power, half power, and full power was $3.7{\pm}0.2kW$, $15.2{\pm}1.2kW$, and $30.7{\pm}2.5kW$, respectively. The thermal power obtained by the slope method at half power and full power was $15.8{\pm}0.7kW$ and $30.2{\pm}1.5kW$, respectively. It was observed that the slope method is more accurate with deviations of 4% and 5% for calibrations at half and full power, respectively, although the linear fit (slope method) on average temperature-rising rates during the thermal power calibration procedure at low power (3.6 kW) is not fitting. As such, the slope method of power calibration is not suitable at lower power for NIRR-1.

• Journal of the Korean Mathematical Society
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• v.55 no.1
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• pp.211-224
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• 2018

We consider a certain three dimensional Euler flow with infinite energy, which is sometimes called the columnar or two and half dimensional flow. We prove the global smoothness of such flow in ${\mathbb{R}}^3$ when the initial data is in some Sobolev or Besov spaces and ${\partial}_3u_3$ is nonnegative.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.513-517
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• 1995

In this paper, a relation of matrix Q in cost function to distances between the closed-loop and open-loop poles of a multi input controllable systems is studied. Futhmore, the state feedback gain with exact desired eigenvalues in the LQR is computed. The proposed scheme is applied to designing automotive active suspension control system for a half-car model and its performance is compared with the existing LQR control system design methodology.

• YAKHAK HOEJI
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• v.29 no.4
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• pp.216-219
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• 1985

The phormacokinetics of acetaminophen were investigated in rabbits with folate-induced renal failure. The blood level, the area under the blood concentraction curve(AUC) and the biological half-life were increased significantly, and the urinary excretion was decreased significantly as compared with those of normal rabbits. Serum creatinine concentration and AUC, creatinine clearance and renal clearance have linear relationship respectively. Dosage regimen of acetaminophen was considered to be adjusted in renal failure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.10A
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• pp.1598-1603
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• 2000

In this paper, an efficient pulse shaping filter architecture for SSB/BPSK-DS/CDMA is proposed. The filter satisfies the specifications in IS-95. The proposed architecture is based on polyphase decomposition and look-up table method. By exploiting the linear phase property of the decomposed filter coefficients, the chip area required for look-up table can be reduced by half compared with the conventional methods. By Synopsys simulations, it is shown that the use of the proposed method can result in reduction in the number of gates by 40%.

• Communications of the Korean Mathematical Society
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• v.16 no.3
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• pp.399-404
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• 2001

We examine plane waves of the elastic reduced wave equation in the half-space, and show that linear combinations of them can cover all plane waves on the boundary. The proof is based on the complex analysis for the symbol in the (dual) variable in the normal direction to the boundary.