• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1140-1153
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• 2016

Since the inception of nuclear power as a commercial energy source, safety has been recognized as a prime consideration in the design, construction, operation, maintenance, and decommissioning of nuclear power plants. The release of radioactivity to the environment requires the failure of multiple safety systems and the breach of three physical barriers: fuel cladding, the reactor cooling system, and containment. In this study, nuclear reactor containment pressurization has been modeled in a large break-loss of coolant accident (LB-LOCA) by programming single-cell and multicell models in MATLAB. First, containment has been considered as a control volume (single-cell model). In addition, spray operation has been added to this model. In the second step, the single-cell model has been developed into a multicell model to consider the effects of the nodalization and spatial location of cells in the containment pressurization in comparison with the single-cell model. In the third step, the accident has been simulated using the CONTAIN 2.0 code. Finally, Bushehr nuclear power plant (BNPP) containment has been considered as a case study. The results of BNPP containment pressurization due to LB-LOCA have been compared between models, final safety analysis report, and CONTAIN code's results.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.62-72
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• 2017

In this study, liner unit root tests and panel unit root tests to the ratio of city to regional house price were applied to examine the ripple effects across 28 cities in the Yangtze River Delta region. Then invert LM unit root tests with two structural breaks for 10 representative cities were conducted. The results showed that there is overwhelming evidence of the existence of ripple effect in the Yangtze River Delta region, while segmentation is restricted to a small group of cities in which there is no long-run relationship with the Yangtze River Delta region average; compared to no- and one-break case, there is overwhelming evidence of a ripple effect with the LM test with two structural breaks. Furthermore, the results of the Granger causality test showed that changes in house prices in Shanghai, Nanjing and Hangzhou have led to changes in house prices in other cities. The findings of this research make certain contributions to the improvements of research system of ripple effect among regional house prices in the Yangtze River Delta Region,and could be referenced by other markets of other cities.

• Journal of the Korea Convergence Society
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• v.11 no.8
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• pp.223-228
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• 2020

The need to steadily manage healthy hair for a beautiful hairstyle is emerging, and it is time to develop hair cosmetics using natural antioxidants that are harmless to the human body according to the needs of the times. Therefore Max. Load, Max. Stress, Max. Elongation, and breakage on the hair coated with the extract of Ginkgo biloba L. According to the Break Load, Break Stress, Break Elongation, Max. Various convergence property experiments such as modulus and Tangential modulus values were conducted. As a result of research, the hairs coated with Ginkgo biloba extract had an overall increase in intrinsic properties including tensile strength compared to the control group. Through this study, we intend to study the potential of Ginkgo biloba L. as a useful material for hair cosmetics such as permanent wave preparations as well as health supplements and medicines that have been released, and we expect that it will be provided as useful research data for the subsequent development of various hair cosmetics.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.9
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• pp.1043-1048
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• 2014

As micro screws feature reduced screw lengths and pitches, the resulting clamping force diminishes because of the reduced length of the actual joints. The elements of the clamping force are material, geometry, and friction. We studied the shrinking size of the screw and the methods to improve the clamping force by changing the material. We developed a micro screw using SWCH18A and SUS XM7 materials, and obtained the precision and thickness of the pitch through three-dimensional measurement. We also measured the external resistance of the micro screw by applying the Vicker's hardness test and conducted a break surface analysis using a break torque test and SEM for obtaining the break characteristics.

• Elastomers and Composites
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• v.46 no.2
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• pp.132-137
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• 2011

In the present investigation, thermal aging behavior of H-NBR/NBR blend with various H-NBR content was investigated. Mixture of dicumyl peroxide and sulfur were used as a curing agent. The influence of the thermal aging of the H-NBR/NBR blends on the solid state properties such as tensile strength, elongation at break, hardness and abrasion resistance was investigated. Tensile strength was increased with increasing H-NBR content, while abrasion resistance was decreased. Both elongation at break and hardness were not affected by the addition of H-NBR. The properties such as hardness, tensile strength and elongation at break of the aged samples were lower than unaged samples. However, the rate of deterioration of those properties was decreased by increasing the H-NBR content, which indicated that improved thermal aging behavior was obtained by the addition of H-NBR. Abrasion loss was increased with increasing aging time, but it became less by the addition of H-NBR addition.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7091-7094
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• 2013

DNA repair capacity is crucial in maintaining cellular functions and homeostasis. However, it can be altered based on DNA sequence variations in DNA repair genes and this may lead to the development of many diseases including malignancies. Identification of genetic polymorphisms responsible for reduced DNA repair capacity is necessary for better prevention. Homologous recombination (HR), a major double strand break repair pathway, plays a critical role in maintaining the genome stability. The present study was performed to determine the frequency of the HR gene XRCC3 Exon 7 (C18067T, rs861539) polymorphisms in Saudi Arabian population in comparison with epidemiological studies by "MEDLINE" search to equate with global populations. The variant allelic (T) frequency of XRCC3 (C>T) was found to be 39%. Our results suggest that frequency of XRCC3 (C>T) DNA repair gene exhibits distinctive patterns compared with the Saudi Arabian population and this might be attributed to ethnic variation. The present findings may help in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.

• Child Studies in Asia-Pacific Contexts
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• v.3 no.1
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• pp.13-31
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• 2013

The children of sex workers in Bangladesh are denied even the most basic human rights. This article is based on recent research focused on the children of sex workers in the context of their everyday lives. The study focused on access to education and how education could be a vehicle for them to break the vicious cycle of exploitation. This was a mixed method interpretative study which employed qualitative and quantitative approaches, but in this paper only qualitative data which was generated through in-depth interviews and focus group discussions is used. Data was collected from sex workers, their children, teachers and NGO workers who participated in the study. Information has been collected for analysing the expectation of the children of sex workers and hope for the future, and the opportunities available to them during their schooling. Thematic analysis technique was used to understand the challenges and barriers faced by the children of sex workers in fulfilling their educational aspirations. The lives of the children of sex workers are marginalised by the mainstream society. Though it is very difficult to break the vicious cycle of exploitation, this research finds that education may be a stepping stone for them to create a better future. However, it is argued that the children of sex workers need income generating vocational and technical education to enable them to earn and support their family. Policy recommendations have been made in order to achieve Education For All targets and Millennium Development Goals, and to provide a second chance for these vulnerable young people to have a better life.

• Nuclear Engineering and Technology
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• v.55 no.1
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• pp.144-155
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• 2023

The core catcher is used as a passive safety system in new generation nuclear power plants to create a space in the containment for the placing and cooling of the molten corium under various severe accidents. This research investigates the role of the core catcher in the VVER-1000 reactor containment system in mitigating the effects of core meltdown under various severe accidents within the context of the Ex-vessel Melt Retention (EVMR) strategy. Hence, a comparison study of three severe accidents is conducted, including Station Black-Out (SBO), SBO combined with the Large Break Loss of Coolant Accident (LB-LOCA), and SBO combined with the Small Break Loss of Coolant Accident (SB-LOCA). Numerical comparative simulations are performed for the aforementioned scenario with and without the EX-vessel core-catcher. The results showed that considering the EX-Vessel core catcher reduces the amount of hydrogen by about 18.2 percent in the case of SBO + LB-LOCA, and hydrogen production decreases by 12.4 percent in the case of SBO + SB-LOCA. Furthermore, in the presence of an EX-Vessel core-catcher, the production of gases such as CO and CO2 for the SBO accident is negligible. It was revealed that the greatest decrease in pressure and temperature of the containment is related to the SBO accident.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.227-232
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• 1993

The temperature dependence of $Na^+-dependent$ succinate uptake was studied in brush border (BBMV) and basolateral (BLMV) membrane vesicles isolated from the rabbit kidney cortex. The succinate uptake was markedly altered by temperature in a similar fashion in both membranes. The temperature dependence was characterized by a nonlinear Arrhenius plot with a break point at 22 and $25^{\circ}C$ for BBMV and BLMV, respectively. The activation energy was 3.91 and 17.09 kcal/mole at above and below the break point respectively, far BBMV; 2.65 and 14.05 kcal/mole, respectively, for BLMV. When temperature increased f개m 20 to $35^{\circ}C$, the Vmax of succinate transport increased from $3.49{\pm}0.11\;to\;5.90{\pm}0.86\;nmole/mg/5\;sec$ for BBMV and from $2.86{\pm}0.25\;to\;3.63{\pm}0.32\;nmole/mg/5\;sec$ for BLMV, with no change in Km in both membranes. These results suggest that renal dicarboxylate transport is similarly sensitive to a change in membrane physical state in BBMV and BLMV.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1026-1035
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• 2015

Condensin is not only responsible for chromosome condensation, but is also involved in double-strand break (DSB) processing in the cell cycle. During meiosis, the condensin complex serves as a component of the meiotic chromosome axis, and mediates both proper assembly of the synaptonemal complex and DSB repair, in order to ensure proper homologous chromosome segregation. Here, we used the budding yeast Saccharomyces cerevisiae to show that condensin participates in a variety of chromosome organization processes and exhibits crucial molecular functions that contribute to meiotic recombination during meiotic prophase I. We demonstrate that Ycs4 is required for efficient DSB formation and establishing homolog bias at the early stage of meiotic prophase I, which allows efficient formation of interhomolog recombination products. In the Ycs4 meiosis-specific allele (ycs4S), interhomolog products were formed at substantial levels, but with the same reduction in crossovers and noncrossovers. We further show that, in prophase chromosomal events, ycs4S relieved the defects in the progression of recombination interactions induced as a result of the absence of Rec8. These results suggest that condensin is a crucial coordinator of the recombination process and chromosome organization during meiosis.