• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.6
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• pp.763-773
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• 2022

Industrial and environmental facilities, which are national growth engine, must sustain their structural safety and maintain their process to continue production activities under various load conditions including natural hazards. In this study, by improving existing design codes which aim to secure the structural safety only, new structural and seismic design codes are proposed to secure both the structural safety and the operability of facilities. In the proposed structural design code, a variety of loads to reflect the characteristics of industrial and environmental facilities are considered and load combinations for the ultimate strength design and the allowable stress design of structures are suggested. Considering the importance of a unit industrial facility and that of a unit process, the seismic design class, design earthquake, and seismic performance level of a unit component are determined to achieve the dual seismic performance objectives for securing both the structural safety and the operability. Also, the proposed design code are applied to an example of an environmental facility in order to examine its applicability.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.267-279
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• 2023

The purpose of this study is to find out the experience and meaning of discrimination among Korean-Chinese part-time job international students. To this end, after in-depth interviews with nine Korean-Chinese part-time job international students from May to June 2022, the data were analyzed using Colaizzi's phenomenological research method. The findings were as follows: New challenges for living expenses and efficient adaptation, this road full of thorns, efforts to adapt beyond discrimination, growth and relationships through part-time jobs turned out to be opportunities. This experience became a process for Korean-Chinese part-time international students to grow further as well as solve economic problems. However, they are subject to multiple discrimination due to their dual status as international students and ethnic Korean-Chinese. Their Korean identity gives a more directed differential experience in the process of working part-time. But in the process, they are still overcoming difficulties. Korean-Chinese international students are growing up by accepting discrimination experiences and adapting to their international life. As a result of the above research, we need education and help to guarantee working human rights for Korean-Chinese part-time students with the development of a multicultural society in the future.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.343-356
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• 2016

The Korea Radioactive Waste Agency (KORAD) has developed a dual-purpose metal cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. The metal cask was designed in compliance with international and domestic technology standards, and safety was the most important consideration in developing the design. It was designed to maintain its integrity for 50 years in terms of major safety factors. The metal cask ensures the minimization of waste generated by maintenance activities during the storage period as well as the safe management of the waste. An activation evaluation of the main body, which includes internal and external components of metal casks whose design lifetime has expired, provides quantitative data on their radioactive inventory. The radioactive inventory of the main body and the components of the metal cask were calculated by applying the MCNP5 ORIGEN-2 evaluation system and by considering each component's chemical composition, neutron flux distribution, and reaction rate, as well as the duration of neutron irradiation during the storage period. The evaluation results revealed that 10 years after the end of the cask's design life, $^{60}Co$ had greater radioactivity than other nuclides among the metal materials. In the case of the neutron shield, nuclides that emit high-energy gamma rays such as $^{28}Al$ and $^{24}Na$ had greater radioactivity immediately after the design lifetime. However, their radioactivity level became negligible after six months due to their short half-life. The surface exposure dose rates of the canister and the main body of the metal cask from which the spent nuclear fuel had been removed with expiration of the design lifetime were determined to be at very low levels, and the radiation exposure doses to which radiation workers were subjected during the decommissioning process appeared to be at insignificant levels. The evaluations of this study strongly suggest that the nuclide inventory of a spent nuclear fuel metal cask can be utilized as basic data when decommissioning of a metal cask is planned, for example, for the development of a decommissioning plan, the determination of a decommissioning method, the estimation of radiation exposure to workers engaged in decommissioning operations, the management/reuse of radioactive wastes, etc.

• Journal of the Korea Institute of Building Construction
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• v.3 no.1
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• pp.107-114
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• 2003

This study aims to find methods that prevents aging of buildings paint coating and that limits defects in construction. Defects in painting can occur in four stages: pure paint, during painting, after the paint coating has dried, and after some period of time has passed after coating. Paint may become bad due to precipitation of pigments, formation of membranes, and seeding during manufacturing. Therefore, it is important that the paint is well mixed and kept airtight at a cool, dark place. Indents, paint brush strokes, orange peel, separation of colors, and paint running and spreading during the paint work process can be prevented by using high quality materials and applying a high-level of construction method. After the paint coating has dried, boiling, yellowing, poor drying, poor bonding, and/or glen deficiency may occur. These are influenced by the levels of cleanness of the dried product, drying temperature and hydration. Then, when the coating has been left dried for some period of time, cracking, peeling, scaling, swelling, discoloring, and/or rusting may develop due to the ultraviolet and contaminants in the air. Since these defects occur due to inappropriate construction schedule and/or hot and humid condition, one must use weatherproof materials. Furthermore, poor paint color may be caused by contamination in the sample plate, discoloration, and/or discrepancies in colors which are due to material differences, level of glossiness, degree of dispersion, dual color property of metallic colors, precipitation of pigments, etc. One should achieve reduction in construction cost and effectiveness in paint work by limiting contaminations in the construction site and strictly observing to construction regulations.

• Journal of Sasang Constitutional Medicine
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• v.18 no.2
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• pp.34-40
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• 2006

1. Objectives We are going to develope 3D Face Recognition Apparatus to analyse the facial characteristics of the Sasangin. In the process, we should identify the recognition rate of the three dimensional position using this Apparatus. 2. Methods We took a photograph of calibrator($280{\times}400mm$) with interval of 20mm longitudinal direction of 10 times using 3D Face Recognition Apparatus. In the practice, we obtained 967 point to the exclusion of points deviating from the visual field of dual camera. And we made a comparison between measurement values and three dimensional standard values to calculate the errors. 3. Results and Conclusions In this test, the average error rate of X axis values was 0.019% and the maximum error rate of X axis values was 0.033%, the average error rate of Y axis values was 0.025% and the maximum error rate of Y axis values was 0.044%, the average error rate of Z axis values was 0.158% and the maximum error rate of Z axis values was 0.269%. This results exhibit much improvement upon the average error rate 1% and the maximum error rate 2.242% of the existing 3D Recognition Apparatus. In conclusion, we assessed that this apparatus was adaptable to abstract the facial characteristic point from three dimensional face shape in the mechanical aspects.

• Journal of Digital Convergence
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• v.11 no.2
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• pp.43-50
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• 2013

Recently, Cyber threats that is doing intelligence and sophistication from the organization's information assets to secure order technical disciplines, as well as managerial and environmental sectors, such as mind-response system is must established. In this paper, possible to analyze the case for the theory in network security, such as the logical network and physical network separation suitable for the corporate environment and constantly respond and manage the Information Security Management Model A secure network design is proposed. In particular, the proposed model improvements derived from the existing network, network improvements have been made in order to design improved ability to respond to real-time security and central manageability, security threats, pre-emptive detection and proactive coping, critical equipment in the event of a dual hwalreu through applied features such as high-availability, high-performance, high-reliability, ensuring separation of individual network security policy integrated management of individual network, network security directional.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.723-732
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• 2013

We investigated the inducing effects of Rubus coreanus extract (RCE) on apoptosis and its related gene expressions in human breast cancer cells. MDA-MB-231 cells were cultured in the presence of 0, 200, 300, and $400{\mu}g/mL$ RCE for 24h. MTT assay demonstrated that relative cell viability measured a decrease in a dose-dependent manner (p<0.05). This dependency was also found in the increasing levels of cell death by a dual staining with Hoechst 33322 and propidium iodide (p<0.05). These close associations was also observed by different stages of apoptotic processes, as shown by an Apoptosis Detection Kit. To determine whether the alterations in such cell activities obtained above cause the induction of apoptotic genes, PT-PCR was performed expressions of both Bcl-2 and Bax mRNAs. The Bcl-2/Bax ratio which is an important indicator of apoptosis, was found to have significantly decreased dose dependence (p<0.05). Western blot analysis also demonstrated that Caspase-3 significantly increases in a dose-dependent manner (p<0.05) in addition to similar alterations of other proteins examined. Taken these results together, the ethanolic RCE used induces a reduction in cell viability along with increased membrane permeability. This leads to a precautious apoptotic process and, subsequently, cell death through the apoptotic pathway involving Bax and Caspase-3 in human breast cancer MDA-MB-231 cells.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.123-131
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• 2002

Solvolyses rate constant of 1- and 2- naphthoyl chlorides (1 and 2) are reported for aqueous binary mixtures with methanol, ethanol, fluorinated alcohol, acetonitrile and dioxane. Kinetic solvent isotope effects (KISE) in methanol and product selectivities (S) of 2-naphthoyl chloride (2) in alcohol-water are also reported. Dispersions in Grunwald-Winstein correlations $(r{\leq}0.901)$ are discussed by multiple regression analysis incorporating ionizing power $(Y_{Cl})$ scale and rate-rate profiles. Major causes for these phenomena are investigated as an aromatic ring solvation effects, in conjunction with weakly nucleophilic solvation effects ($S_N2$ character), for solvolyses of 1 and for solvolyses of 2, as dual reaction channels, described as $S_N1$-$S_N2$ and $S_AN$-$S_N2$ processes. Distinct border lines between the two pathways are derived from solvolyses rates of 2 in 18 solvent using the results of $log(k/k_o)=mY_{Cl}+lN_T+hI$ plot with values of 1.13 for m, 0.37 for l and 0.15 for h value in 5 aqueous fluorinated alcohol mixtures. Using rate-product correlation, the validity of a third order model based on a general base catalyzed by solvent and contribution from these rate constants, $k_{aa},\;k_{aw}$ and $k_{aw}$, are investigated for $S_AN$-$S_N2$ solvolyses of 2 favored in more rich alcohol media and gradual addition of water to alcohol solvent shows a great shift away from stoichiometric solvation to predominantly medium effects. Rate-rate correlation between solvolyses of 2 and trimethyl acetylchloride (5) with alkyl group in the 29 aqueous solvent mixtures shows appreciable linearity (slope = 0.84, r = 0.987), caused by the same pathway ($S_N1$-$S_N2$ process), even if this correlation coincides with appreciable dispersion (different solvation effect).

• The Journal of Advanced Prosthodontics
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• v.9 no.2
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• pp.85-92
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• 2017

PURPOSE. The aim of this study was to evaluate the effect of tooth surface pre-treatment steps on shear bond strength, which is essential for understanding the adhesive cementation process. MATERIALS AND METHODS. Shear bond strengths of different cements with various tooth surface treatments (none, etching, priming, or etching and priming) on enamel and dentin of human teeth were measured using the Swiss shear test design. Three adhesives (Permaflo DC, Panavia F 2.0, and Panavia V5) and one self-adhesive cement (Panavia SA plus) were included in this study. The interface of the cement and the tooth surface with the different pre-treatments was analyzed using SEM. pH values of the cements and primers were measured. RESULTS. The highest bond strength values for all cements were achieved with etching and primer on enamel ($25.6{\pm}5.3-32.3{\pm}10.4MPa$). On dentin, etching and priming produced the highest bond strength values for all cements ($8.6{\pm}2.9-11.7{\pm}3.5MPa$) except for Panavia V5, which achieved significantly higher bond strengths when pre-treated with primer only ($15.3{\pm}4.1MPa$). Shear bond strength values were correlated with the micro-retentive surface topography of enamel and the tag length on dentin except for Panavia V5, which revealed the highest bond strength with primer application only without etching, resulting in short but sturdy tags. CONCLUSION. The highest bond strength can be achieved for Panavia F 2.0, Permaflo DC, and Panavia SA plus when the tooth substrate is previously etched and the respective primer is applied. The new cement Panavia V5 displayed low technique-sensitivity and attained significantly higher adhesion of all tested cements to dentin when only primer was applied.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1798-1807
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• 2017

The differentiations in nitrogen-converting activity and microbial community structure between granular size fractions in a continuous completely autotrophic nitrogen removal over nitrite (CANON) reactor, having a superior specific nitrogen removal rate of $0.24g/(g\;VSS{\cdot}h)$, were investigated by batch tests and high-throughput pyrosequencing analysis, respectively. Results revealed that a high dissolved oxygen concentration (>1.8 mg/l) could result in efficient nitrite accumulation with small granules (0.2-0.6 mm in diameter), because aerobic ammonium-oxidizing bacteria (genus Nitrosomonas) predominated therein. Meanwhile, intermediate size granules (1.4-2.0 mm in diameter) showed the highest nitrogen removal activity of $40.4mg/(g\;VSS{\cdot}h)$ under sufficient oxygen supply, corresponding to the relative abundance ratio of aerobic to anaerobic ammonium-oxidizing bacteria (genus Candidatus Kuenenia) of 5.7. Additionally, a dual substrate competition for oxygen and nitrite would be considered as the main mechanism for repression of nitrite-oxidizing bacteria, and the few Nitrospira spp. did not remarkably affect the overall performance of the reactor. Because all the granular size fractions could accomplish the CANON process independently under oxygen limiting conditions, maintaining a diversity of granular size would facilitate the stability of the suspended growth CANON system.