• Journal of Radiation Protection and Research
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• v.37 no.4
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• pp.197-201
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• 2012

Annual dose at the boundary of the interim storage facility at normal condition was calculated to estimate the site area of the facility of PWR spent nuclear fuel. In this work, source term was generated by ORIGEN-ARP for 4.5 wt% initial enrichment, 45,000 MWd/MTU burnup and 10 years cooling time. Modeling of the storage facilities and radiation shielding evaluations were conducted by MCNP code depending on the storage capacity. In the case of the centralized storage system, the required site area was found to have the radius of more than 700 m.

• Journal of the Korean Institute of Gas
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• v.7 no.3 s.20
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• pp.44-50
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• 2003

The axisymmetric methane-air counterflow flame was simulated to investigate changes in the flame structure due to the fuel concentration and to evaluate the numerical method. The global strain rates $a_g=20,\;60,\;90\;s^{-1}$ and the mole fractions of methane $x_m=20,\;50,\;80\%$ in the fuel stream were taken to be numerical parameters. The axisymmetric simulation was conducted by using the Fire Dynamics Simulator (FDS) which employed a mixture fraction combustion model, and the results were compared with those of OPPDIF, which is an one-dimensional flamelet code and includes detail chemical reactions. In all the cases tested, there was good agreement in the temperature and axial velocity profiles between the axisymmetric and one-dimensional simulations. It was shown that the flame thickness and peak flame temperature increase and the flame radius decreases as the fuel concentration increases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.403-410
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• 2009

This study was conducted to investigate the hygienic quality of commercial Kwamegi, a Korean traditional food, made from semi-dried Pacific saury. The hygienic qualities of 10 Kwamegi samples were examined from the 15 commercially available types. Samples with code 3, 4, 6, 11 and 12 were acceptable based on criteria suggested by Ministry for Food, Agriculture, Forestry and Fisheries (i.e. moisture below 50%, total mercury below 0.5 ppm, lead below 2.0 ppm, viable cells below $1.0{\times}10^5$ CFU/g and coliform count below $1.0{\times}10^3$ MPN/100g. Peroxide value of commercial Kwamegi ranged from 15.3-104.1 meq/kg. Agmatine sulfate, cadaverine, histamine, tyramine, spermidine, dopamine and spermine were found in all of the 15 commercially available Kwamegi, while tryptamine and 2-phenylethylamine were not detected. Putrescine dihydrochloride was only detected in 7 samples. The histamine content of commercial Kwamegi ranged from 33-124mg/kg, which is believed to be an acceptable limit according to guidelines from other countries. Cadaverine can be used as a potential index for freshness of commercial Kwamegi as there is a good correlation between volatile basic nitrogen and biogenic amine contents.

• Earthquakes and Structures
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• v.12 no.1
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• pp.135-144
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• 2017

Near-fault ground motions are characterized by high values of the ratio between the peak of vertical and horizontal ground accelerations, which can significantly affect the nonlinear response of a base-isolated structure. To check the effectiveness of different base-isolation systems for retrofitting a r.c. framed structure located in a near-fault area, a numerical investigation is carried out analyzing the nonlinear dynamic response of the fixed-base and isolated structures. For this purpose, a six-storey r.c. framed building is supposed to be retrofitted by insertion of an isolation system at the base for attaining performance levels imposed by current Italian code in a high-risk seismic zone. In particular, elastomeric (e.g., high-damping-laminated-rubber bearings, HDLRBs) and friction (e.g., steel-PTFE sliding bearings, SBs, or friction pendulum bearings, FPBs) isolators are considered, with reference to three cases of base isolation: HDLRBs acting alone (i.e., EBI structures); in-parallel combination of HDLRBs and SBs (i.e., EFBI structures); FPBs acting alone (i.e., FPBI structures). Different values of the stiffness ratio, defined as the ratio between the vertical and horizontal stiffnesses of the HDLRBs, sliding ratio, defined as the global sliding force divided by the maximum sliding force of the SBs, and in-plan distribution of friction coefficient for the FPs are investigated. The EBI, EFBI and FPBI base-isolation systems are designed assuming the same values of the fundamental vibration period and equivalent viscous damping ratio. The nonlinear dynamic analysis is carried out with reference to near-fault earthquakes, selected and scaled on the design hypotheses adopted for the test structures.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.75-92
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• 1999

In this paper, the seismic analysis model for seismically isolated KALIMER reactor structures is developed and the modal analysis and the seismic time history analysis are carried out for seismic isolation and non-isolation cases. To check the seismic stress limit according to the ASME Code, the equivalent seismic stress analyses are preformed using the 3-D finite element model. From the seismic stress analysis, the seismic margins are calculated for structural members. The limit of seismic load is defined to show that the maximum input acceleration ensures the structural safety for seismic load. In comparison of seismic responses between seismic isolation and non-isolation cases, the seismic isolation design gives significantly reduced acceleration responses and relative displacements between structures. The seismic margin of KALIMER reactor structure is high enough to produce the limit seismic load 0.8g.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.45-55
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• 2010

While Long Term Evolution-Frequency Division Duplexing (LTE-FDD) is regarded as one of the strong candidates for "4G" wireless broadband access in FDD field, LTE-Time Division Duplexing (TDD) is emerging as one possible migration path for WiMAX-TDD in some cases as well as the migration path for Time Division-Synchronous Code Division Multiple Access (TD-SCDMA). In this paper, we analyze the feasibility of dual mode with LTE-TDD in two combinations: dual mode LTE-FDD/TDD and dual mode Worldwide Interoperability for Microwave Access (WiMAX)-TDD/LTE-TDD. Thanks to the commonality in numerology, terminology, and frame structure between LTE-FDD and LTE-TDD, dual mode LTE-FDD/TDD looks feasible in a cost-effective manner. Thanks to the commonality in scheduling algorithm, control mechanism, and supported spectrum bands, it is shown that dual mode WiMAX-TDD/LTE-TDD looks feasible as well. It should be also noted that the commonality in numerology and frame structure is critical for building a chip while the commonality in algorithms and control mechanisms is critical to make it work.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.9
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• pp.1000-1009
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• 2008

The purpose of this paper is to analyze the performance of MB-OFDM UWB system when the interference signal that can be WIMAX signal or 4 G system signal is received by detection limit of -80 dBm/MHz proposed in Korea for DAA(Detect And Avoid) to permit UWB in $3.1{\sim}4.8$ GHz. MB-OFDM UWB system supports two transmission modes; one is TFI(Time frequency Interleaving) mode that transmits OFDM symbols using different carrier frequency from symbol to symbol according to Time Frequency(TF) codes, the other is FFI(Fixed Frequency Interleaving) mode that transmits OFDM symbols using a specific carrier frequency. In this paper, we considered the TX average power and the synchronization structure to reflect the effect of frequency hopping according to TFC. Interference analysis results show that the WiMAX system is fenced thoroughly from UWB interference in domestic DAA regulation, but the performance of MB-OFDM UWB system is degraded seriously by an interference signal with the DAA detection limit even in frequency Hopping mode that can get frequency diversity effect.

• Korean Journal of Clinical Pharmacy
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• v.27 no.3
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• pp.127-135
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• 2017

Background: Kawasaki disease (KD) is an acute febrile, systemic vasculitis as a leading cause of acquired heart disease in children. Intravenous immunoglobulin G (IVIG) and aspirin are the standard initial therapy in the treatment of acute KD. The purpose of this study was to investigate drug utilization in children with KD, and to compare "IVIG + high-dose aspirin" and "IVIG + moderate-dose aspirin" in preventing cardiac complications. Methods: We analyzed pediatric patient sample data compiled by the Health Insurance Review & Assessment Service from 2010 to 2015. We identified patients with KD using the KCD-6 code of M30.3. We excluded patients in chronic phase or ${\geq}1$0 years. We also excluded patients who were diagnosed KD in November or December. Drug utilization pattern were assessed in acute KD patients and 30-day and 60-day cardiac complications were investigated between "IVIG + high-dose aspirin" group and "IVIG + moderate-dose aspirin" group. Results: In acute phase, IVIG was administered to 95.8% patients, and 57.1% patients were prescribed moderate-dose aspirin and 25% patients were with high-dose aspirin. Steroid use was rapidly increased from 4.0% in 2010 to 11.3% in 2015. Both 30-day and 60-day cardiac complications occurred less in "IVIG + high-dose aspirin" group compared to "IVIG + moderate-dose aspirin" group, but not statistically significant (0.9% vs 1.8%, p=0.252 for 30-day complication rate; 1.5% vs 2.7%. p=0.073 for 60-day complication rate). Conclusion: We were not able to demonstrate which aspirin therapy is superior for preventing cardiac complications in acute KD patients and further research is warranted.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.4
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• pp.80-87
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• 2007

In this paper, link-level performance of a OFDMA technique, which has been considered as a standard for 802.16, 802.20, 3G-LTE, WiMax, and WiBro, is evaluated for next-generation wireless communication systems. While many researches have focused on uncoded forward-link performances, this paper provides a coded performance of a reverse-link OFDMA system. Performance degradation due to time offset among reverse-link users and frequency offset during FFT process is investigated. Transmitter and receiver antenna diversity techniques are used to overcome performance degradation. Performance of a OFDMA system is compared with a CDMA system in terms of FER and throughput to emphasize the advantage of OFDMA system for a reverse-link. Finally, under given specification, Eb/No required to achieve the maximum throughput of a reverse-link is proposed considering various coded rates and antenna permutations.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.78-87
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• 1988

This article suggests the radionuclides which should be considered more important to the offsite consequence assesment during a nuclear power plant accident. For this purpose, the relative importance to the early health effects of released radionuclides on the major organs during the accident is estimated under the assumption of the same release fraction. The inventories of the 25 elements, 54 nuclides selected in the Reactor Safety Study are calculated by ORIGEN 2 code. The organs of interest in the estimation are G. I. track, bone marrow, thyroid and lung. The result shows the relative potential importance of radionuclides as follows: For G.I. track, Np, Ce, Ru, Y, and Zr are of importance in sequence, Np, I, La, Sr, Ba for bone marrow, I and Te for thyroid, Cm, Ce, Ru, Pu, Zr for lung. In addition to iodine and noble gases, therefore, the potential contribution of those nuclides listed above to the offsite consequences should not be overlooked for some accidents of particular sequence.