• Fire Science and Engineering
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• v.34 no.1
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• pp.89-102
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• 2020

Chemical terrorism using toxic and flammable gases, which could be fatal to the health of the human body, poses a serious threat to the security of most advanced countries, as well as those that are suffering from local disputes, due to the asymmetric information that exists between terrorist actors and victims. The countermeasures against chemical terrorism can be roughly divided into three stages: prevention, response, and probation. The critical factors for each professional response agency, and the personnel that determine the degree and range of chemical terrorism damage, are performing missions successfully in the process of the prevention and the response stage against chemical terrorism. To do this, conducting objective and systematical assessments on facilities that could potentially be the subject of chemical terrorism is more important than anything. In this study, we compared the existing domestic and foreign vulnerable classification systems for chemical terrorism, reviewed the current direction of improvement in domestic classification systems, and suggested more scientific and systematic methodologies through the vulnerability assessment on an actual public facility sample.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.5
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• pp.596-604
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• 2016

In this study, we used a stochastic approach for guaranteeing the reliability and robustness of the performance with regard to the design of polymer components, while taking into consideration the degradation properties and operating conditions in automobiles. Creep and tensile tests were performed for obtaining degradation properties. The Prony series, which described the viscoelastic models, were calculated to use the creep data by the Maxwell fluid model. We obtained the stress data from the frequency response analysis of the polymer components while considering the degradation properties. Limit state functions are generated by using these data. Reliability assessments are conducted under the variation of the degradation properties and area of frequency at peak response. For this study, the input parameters are assumed to be a normal distribution, and the reliability under the yield stress criteria is evaluated by using the Monte Carlo Simulation. As a result, the reliabilities, according to the three types of polymer materials in automotive components, are compared to each other and suggested the applicable possibility of polymeric materials in automobiles.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.6
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• pp.401-409
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• 2020

Seismic fragility assessments include a procedure to combine the random variables of response and capacity to produce the relationship between failure probability and seismic intensity. The evaluation of the failure probability of simultaneous multiple failures of two or more components assumes that the failure probability of each component is independent of those of the others. However, a correlation is expected to exist because several random factors have the same cause. The multiple-failure probability can differ depending on this correlation and may be unconservative without considering the seismic correlation. Therefore, a practical methodology for fragility assessment should be evaluated using the seismic correlation and correlation coefficient for each random variable. In this study, several random variables were selected for numerical evaluation of the correlation coefficient. The correlation coefficient was then compared with each variable and the combined variables. The correlation coefficient using simplified and complex models were also compared to determine and analyze the differences between each of the approaches.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.1949-1958
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• 2023

The International Commission on Radiological Protection (ICRP) Publication 116 was released to provide a comprehensive dataset of the dose coefficients (DCs) for external exposures produced with the adult reference voxel phantoms of ICRP Publication 110. Although an advanced skeletal dosimetry method for photons and neutrons using fluence-to-dose response functions (DRFs) was introduced in ICRP Publication 116, the ICRP-116 skeletal DCs were calculated by using the simple method conventionally used (i.e., doses to red bone marrow and endosteum approximated by doses to spongiosa and/or medullary cavities). In the present study, the photon and neutron DRFs were used to produce skeletal DCs of the ICRP-110 reference phantoms, which were then compared with the ICRP-116 DCs. For photons, there were significant differences by up to ~2.8 times especially at energies <0.3 MeV. For neutrons, the differences were generally small over the entire energy region (mostly <20%). The general impact of the DRF-based skeletal DCs on the effective dose calculations was negligibly small, supporting the validity of the ICRP-116 effective DCs despite their skeletal DCs derived from the simple method. Meanwhile, we believe that the DRF-based skeletal DCs could be beneficial in better estimates of skeletal doses of individuals for risk assessments.

• Structural Monitoring and Maintenance
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• v.10 no.3
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• pp.207-220
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• 2023

The safety of bridges are critical in our transportation infrastructure. Bridge design and analysis require complex structural analysis procedures to ensure their safety and stability. One common method is to calculate the maximum moment in the girders to determine the appropriate bridge section. Girder distribution factors (GDFs) provide a simpler approach for performing this analysis. A GDF is a ratio between the response of a single girder and the total response of all girders in the bridge. This paper explores the significance of GDFs in bridge analysis and design, including their importance in the evaluation of existing bridges. We utilized Bridge Weigh-in-motion (B-WIM) measurements of five simple supported girder bridge in Indonesia to develop a simple GDF provisions for the Indonesia's bridge design code. The B-WIM measurements enable us to know each girder strain as a response due to vehicle loading as the vehicle passes the bridge. The calculated GDF obtained from the B-WIM measurements were compared with the code-specified GDF and the American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) bridge design specification. Our study found that the code specified GDF was adequate or conservative compared to the GDF obtained from the B-WIM measurements. The proposed GDF equation correlates well with the AASHTO LRFD bridge design specification. Developing appropriate provisions for GDFs in Indonesian bridge design codes can provides a practical solution for designing girder bridges in Indonesia, ensuring safety while allowing for easier calculations and assessments based on B-WIM measurements.

• Journal of The Korean Association For Science Education
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• v.35 no.5
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• pp.907-917
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• 2015

Response to Intervention (RTI), which is focused on the gap between pre-interventions and post-interventions, provides an effective intervention program. This study takes under-achievement factors into consideration to determine the overall characteristics of underachievers. The under-achievement factors include cognitive learning factors, affective factors, and environmental factors. This study conducted curriculum-based assessments, achievement tests, and assessments on attitudes toward science and science learning motivation to verify the effects of individually tailored teaching according to the types of under-achievement in science. The experimental group was composed of six students in fourth grade, and the comparison group had 23 students. The findings of the study were as follows. First, the performance and progress of underachievers in the first-stage showed little progress and did not reach grade-level performance. Second, the underachievers in the second-stage greatly improved. In particular, the average of eight sessions in the second-step demonstrated performance beyond that of the regular child. Third, individually tailored teaching according to the types of under-achievement in science positively affected attitudes toward science and science learning motivation. This study will contribute to the improvement of the underachiever by applying individually tailored teaching according to the types of under-achievement in science.

• Journal of the Earthquake Engineering Society of Korea
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• v.16 no.3
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• pp.35-42
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• 2012

We propose a probabilistic method to evaluate the uniform hazard spectra (UHS) of the soil of nuclear power plant(NPP) sites corresponding to that of a bedrock site. To do this, amplification factors on the surface of soil sites were estimated through site response analysis while considering the uncertainty in the earthquake ground motion and soil deposit characteristics. The amplification factors were calculated by regression analysis with spectral acceleration because these two factors are mostly correlated. The proposed method was applied to the evaluation of UHS for the KNGR (Korean Next Generation Reactor) and the APR1400 (Advanced Power Reactor 1400) nuclear power plant sites of B1, B4, C1 and C3. The most dominant frequency range with respect to the annual frequency of earthquakes was evaluated from the UHS analysis. It can be expected that the proposed method will improve the results of integrated risk assessments of NPPs rationally. We expect also that the proposed method will be applied to the evaluation of the UHS and of many other kinds of soil sites.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1025-1031
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• 2008

S-Adenosyl-L-methionine (SAM) exerts several beneficial effects on depression, chronic diseases, and cognitive impairments. Bifidobactrium bifidum BGN4 reportedly produces higher amounts of SAM than any other lactic acid bacterium used in yogurt. The aim of this study was to develop a SAM-reinforced probiotic yogurt using Bifidobacterium. The sensory aspects of the yogurt via response surface methodology (RSM) and the texture and SAM content of the yogurt were assessed. Based on the sensory assessments for sweetness, sourness, and thickness evaluated by 48 panelists, the optimized conditions for preparation of SAM-reinforced yogurt were 4.0-4.4%(w/w) sugar, 3.2-3.5%(w/w) skim milk, and a pH of 4.7-4.8. The SAM content of the developed yogurt was 0.05 nmol/mL. In conclusion, SAM-reinforced probiotic yogurt may provide a vehicle for the potential exploitation of the benefits of increased dietary SAM.

• Journal of Navigation and Port Research
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• v.28 no.6
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• pp.491-496
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• 2004

The paper describes measurement techniques for an acoustic transfer characteristic of ship's bridge stimulated by a whistle sound The response sounds, according to the opening-shutting conditions of bridge doors for Training Ship ‘SAENURI’, are measured by B＆K 2260D equipment, and then the frequency responses are extracted by B＆K 7830 software. To evaluate the measured transfer characteristic, the 128th order FIR (Finite Impulse Response) filters, containing the different frequency characteristics, are constructed based on the frequency sampling-based design method Using evaluation indexes with six scales, psychological assessments by five subjects are carried out with test sounds which are obtained from convolving the source signal with FIR filters. As results of tests, the test sounds gives $A_S$ 3.3∼4.7 which means the psychological sense of ‘it is almost similar sound as original ones in a real world’, and thus it is clearly seen that the proposed method can be used for the measurement of an acoustic transfer characteristic of ship’s bridge.

• The Journal of Korean Medicine
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• v.25 no.2
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• pp.207-219
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• 2004

Objectives : We investigated to find the relationship between single-nucleotide polymorphism (SNP) of IL4R, IL-10 and bee venom therapy efficacy in patients with RA treated with bee venom for 8 weeks. Methods : Korean RA patients (n=114) and healthy subjects (n=109) were included in this prospective study. Korean bee venom was dissolved in saline (diluted 1:3000) and administrated into acupuncture points. Bee venom therapy was applied twice a week and continued for 8 weeks. The clinical response was evaluated using various assessments before and after treatment. Disease severity was measured by determining the number of tender joints and swollen joints. Laboratory studies included ESR, CRP, and rheumatoid factor. Genotyping for IL-4R and IL-10 polymorphism was done by pyrosequencing analysis. Results : 1. In IL4R genotypes, there was significant difference between RA ptitients tind controls group. 2. In IL4R genotypes, there was significant difference among Good, Mild and Bad responders to in RA patients, but in the frequency of alleles and carriers, there were no significant difference. 3. There was no significant difference between RA patients and controls group in IL-10 gene genotypes. 4. In IL-10 genotypes, there was no significant difference among Good, Mild and Bad responders to in RA patients. 5. There was no significant difference in the improvement of ESR, CRP and KHAQ scores after bee venom therapy in RA patients among the IL4R or IL-10 genotypes. Conclusions : In IL-4R genotypes, there was significant difference between RA patients and control group, and among Good, Mild and Bad responders in RA patients. However, in IL-10 genotypes, there was no significant difference between RA patients and controls group and among Good, Mild and Bad responders in RA patients.