• Journal of the Korean Society for Precision Engineering
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• v.27 no.2
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• pp.40-49
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• 2010

The Purpose of this paper is to weld a rapid palatal expander using a continuous wave Nd:YAG laser. The rapid palatal expander has become a useful treatment method for severe maxillary transverse deficiencies and posterior crossbites. Rapid maxillary expansion is a well-established method to correct transverse maxillary deficiency and arch length discrepancy. The major process parameters studied in the present laser welding experiment were the positions of focus, laser power and travel speed of laser beam. We measured the fusion zone size and its shape using an optical microscope for the observation of cross-sectional area and tension stress of a rapid palatal expander welded. Through the experimental investigation, the optimum speeds and power of laser without deficiencies of weld cross-sectional area were obtained.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.48-64
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• 2002

The primary recognized health risk from common deficiencies in glucose-6-phosphate dehydrogenase (G6PD), a cytoprotective enzyme for oxidative stress, is red blood cell hemolysis. Here we show that litters from untreated pregnant mutant mice with a hereditary G6PD deficiency had increased prenatal (fetal resorptions) and postnatal death. When treated with the anticonvulsant drug phenytoin, a human teratogen that is commonly used in pregnant women and causes embryonic oxidative stress, G6PD-deficient dams had higher embryonic DNA oxidation and more fetal death and birth defects. The reported G6PD gene mutation was confirmed and used to genotype fetal resorptions, which were primarily G6PD deficient. This is the first evidence that G6PD is a developmentally critical cytoprotective enzyme for both endogenous and xenobiotic-initiated embryopathic oxidative stress and DNA damage. G6PD deficiencies accordingly may have a broader biological relevance as important determinants of infertility, in utero and postnatal death, and teratogenesis.-Nicol, C. J., Zielenski, J., Tsui, L.-C., Wells, P. G. An embryoprotective role for glucose-6-phosphate dehydrogenase in developmental oxidative stress and chemical teratogenesis.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.123-126
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• 1999

A successful outcome of pregnancy requires an efficient uteroplacental vascular system. Since this system may be compromised by disorders of haemostasis associated with a prothrombotic state, maternal thrombophilia might be a risk factor for fetal loss. Hereditary deficiencies of the naturally occuring anticoagulants are well recognized conditions predisposing to recurrent venous thromboembolism. Since thrombotic phenomena have been implied as a cause of abortion and stillbirth, these deficiencies might increase the risk of fetal demise. We have experienced a case of antiphospholipid syndrome associated with protein C deficiency in patient with recurrent spontaneous abortion. So we report this case with a brief review of literatures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.213-216
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• 2005

The distress communication system in the maritime mobile service had almost depended on the wireless telephony or telegraphy technique. The GMDSS (Global Maritime Distress and Safety System) which was introduced in 1992 brought a lot of changes in the maritime distress communication service such as the automatic transmission of distress signals and implementation of global search and rescue networks. However, there are some deficiencies in the GMDSS distress communication system such as a lack of compatibility in the maritime distress communication between GMDSS ships and Non-GMDSS ships, increasing deceptive or false distress alerts generated by GMDSS installations, lack of understanding about the GMDSS installations for the operators. In this paper, the problems of distress communication system in the maritime mobile service are analyzed and the methods to solve or minimize these problems are suggested.

• Journal of the Korean Society of Safety
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• v.37 no.2
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• pp.43-53
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• 2022

This paper describes an attempt to improve and optimize the operational safety level of a domestic research reactor by conducting a probabilistic safety assessment (PSA) under full-power operating conditions. The PSA was undertaken to assess the level of safety at an operating research reactor in Korea, to evaluate whether it is probabilistically safe and reliable to operate, and to obtain insights regarding the requisite procedural and design improvements for achieving safer operation. The technical objectives were to use the PSA to identify the accident sequences leading to core damage, and to conduct sensitivity analyses based thereon to derive insights regarding potential design and procedural improvements. Based on the dominant accident sequences identified by the PSA, eight types of sensitivity analysis were performed, and relevant insights for achieving safer operation were derived. When these insights were applied to the reactor design and operating procedure, the risk was found to be reduced by approximately ten times, and the safety was significantly improved. The results demonstrate that the PSA methodology is very effective for improving reactor safety in the full-power operating phase. In particular, it is a highly suitable approach for identifying the deficiencies of a reactor operating at full power, and for improving the reactor safety by overcoming those deficiencies.

• Journal of Fashion Business
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• v.26 no.2
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• pp.83-94
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• 2022

The purpose of this study was to analyze the reality of clothes-wearing among physically disabled women and propose trouser designs. As a research method, an in-depth interview method was adopted for 10 women in their 30s and 50s with lower limb disabilities who could wear trousers and use wheelchairs. The study results identified the following factors that should be considered in the design of trousers. First, a semi-casual design that could hide physical deficiencies, was not different from ready-made clothes and enabled various looks was desirable. Second, the proper material would have little transformation in the form, have remarkable durability and laundry fastness, two-directional stretch, and hide deficiencies with a sense of thickness and density. Third, an "L-frame" pattern in a sitting position, and a straight fit were desirable. Finally, pockets can impose pressure according to their form, size, position, and sewing method, highlighted the need for a sewing approach to minimize seams in the fabric. For adjustment, an elastic band would be a good choice in terms of type, length, position, and material as it could satisfy both the convenience of putting on and taking off and comfort in wearing at the same time. Decorative design details can also impose pressure according to a sense of thickness, which means that they should be avoided in parts that are close to the body or can impose pressure according to posture.

• Structural Engineering and Mechanics
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• v.82 no.5
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• pp.557-569
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• 2022

The retrofit of existing structures in high seismic zones is a crucial issue in the earthquake engineering field. The interest of the research community is particularly high for the structures that do not respect current seismic codes and present structural deficiencies such as poor detailing and lack of capacity design provisions. A reinforced concrete (RC) school building is used as case study to show the influence of different knowledge levels on the seismic retrofitting cost assessment. The safety assessment of the case study building highlights deficiencies under both vertical and seismic loads. By considering all the possible knowledge levels defined by the Italian such as by the European codes in order to derive the mechanical properties of the school building constitutive materials, the retrofit operations are designed to achieve different seismic safety thresholds. The retrofit structural costs are calculated and summed up to the costs for in-situ in tests. The paper shows how for the case study building the major costs spent for a large number of in-situ tests allows to save a consistent amount of money for retrofit operations. The hypothesis of demolition and reconstruction of the building is also compared in terms of costs with all the analyzed retrofit options.

• Nuclear Engineering and Technology
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• v.26 no.2
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• pp.265-276
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• 1994

Several improvements to the RELAP5/MOD3 reflood model hate been made. These improvement were made to correct deficiencies in the reflood model identified by the assessment of the RELAP5/MOD3 code against FLECHT-SEASET experiments. The improvements consist of modification of reflood wall heat transfer package and adjusting the droplet size in dispersed flow regime. The time smoothing of wall vaporization and level tracking of transition flow are also added to eliminate the pressure spikes and level oscillation during reflood process. Assessment of the improved model against FLECHT-SEASET experimental data and application of LBLOCA analysis for plant shows that the deficiencies have been corrected.

• International Journal of Advanced Culture Technology
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• v.12 no.3
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• pp.396-405
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• 2024

This study analyzed the practical issues in the Serious Accident Punishment Act (SAPA) for construction sites and proposed measures to improve provisions that are detached from reality. The Act aims to prevent major accidents across various industries, with a particular emphasis on the construction sector. While the Act's intention is commendable, several significant legal flaws have emerged during its implementation. These issues were critically analyzed and strategic recommendations were proposed. Key issues include ambiguous legal definitions, the differential impact of the law on small and large businesses, and the increased administrative and managerial burdens. This study proposed specific measures to enhance the clarity of legal terminology and technology, balance the responsibilities between small and large businesses, and streamline administrative processes. Additionally, methods for effectively revising the regulations and reasonably complying with them on-site were proposed. By addressing these issues, we aim to improve the effectiveness of the law, ensure fair application, and ultimately create a safer working environment in the construction industry. The recommendations are expected to serve as valuable resources for future revisions and improvements to SAPA and contribute to the broader goal of sustainable industrial safety and development.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.327-337
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• 2019

The purpose of the current study was to examine dual mediation effect of executive function deficiencies and adaptive cognitive emotion regulation strategies in the relation of smartphone addiction and subjective well-being and to suggest implications for adult smartphone addiction intervention programs. A self-report survey was conducted to 148 adults(71 males and 77 females) and the mediation effect was evaluated by regression analyses. Key findings are as follows. First, executive function deficiencies showed mediation effect on the relationship between smartphone addiction and adaptive cognitive emotion regulation strategies. Second, significant mediation effect of adaptive cognitive emotion regulation strategies was not found on the relationship between smartphone addiction and subjective well-being. Finally, the relation of smarphone addiction and subjective well-being was mediated by executive function deficiencies and adaptive cognitive emotion regulation strategies. These results imply that it would be helpful to train executive function and foster emotion regulation strategies to the adult smartphone addiction groups. Finally, limitations of this study and suggestions for future research of the entire adult age group were discussed.