• Journal of Ocean Engineering and Technology
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• v.18 no.1
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• pp.69-74
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• 2004

In general, the protection method of Shell and Tube Type heat exchanger for a vessel has been applied as a sacrificial anode, which is attached at the inner side of the shell. However, this is an insufficient protection method for tube. Therefore, a more suitable method, such as the impressed current cathodic protection for tube protection, is required. Al-brass is the raw material of tubes for heat exchanger of a vessel where seawater is used for cooling the water. It has a high level of heat conductivity, excellent mechanical properties, and a high level of corrosion resistance, due to a cuprous oxide (Cu$_2$O) layer against th seawater. However, in actuality, it has been reported that Al-brass tubes for heat exchanger of a vessel can produce local corrosion, such as stress corrosion cracking (SCC). This paper studied the effect of impressed potential on the stress corrosion cracking of Al-brass for impressed current cathodic protection in 3.5% NaCl +0.1% NH$_4$OH solution, under flow by a constant displacement tester. Based on the test results, the latent time of SCC, stress corrosion crack propagation, and the dezincification phase of Al-brass are investigated.

• Convergence Security Journal
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• v.23 no.1
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• pp.3-8
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• 2023

Multi-domain optical transport networks are not fundamentally interoperable and require an integrated orchestration mechanism and path provision mechanism at the entire network level. In addition, ensuring network survivability is one of the important issues. MPLS-TP (Multi-Protocol Label Switching-Transport Profile) defines various protection/recovery methods as standards, but does not mention how to calculate and select protection/recovery paths. Therefore, an algorithm that minimizes protection/recovery collisions at the optical circuit packet integrated network level and calculates and sets a path that can be rapidly protected/recovered over the entire integrated network area is required. In this paper, we proposed an algorithm that calculates and sets up a path that can be rapidly protected and restored in a T-SDN network composed of multiple ring-mesh topology.

• Korean Journal of Adult Nursing
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• v.28 no.6
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• pp.680-690
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• 2016

Purpose: This study was designed to identify knowledge, attitude, environment, and self-efficacy among perioperative nurses in terms of radiation protection and to describe those factors affecting radiation protection behaviors. Methods: The sample was comprised of 128 perioperative nurses who agreed to participate in this descriptive study. Data were collected from a self-administered questionnaire and were analyzed using the t-test, analysis of variance, Mann-whitney U test, Kruskal-Wallis test, Pearson's correlation, and multiple regression analyses. Results: Radiation protection behaviors were significantly different by participant's gender, length of career as a perioperative nurse, educational level and prior experience with radiation protection education. Radiation protection behaviors were significantly correlated with radiation protection environment and self-efficacy in terms of radiation protection behaviors. In the multiple linear regression models, radiation protection environment and self-efficacy on radiation protection behaviors were statistically significant predictors of radiation protection behaviors, which accounted for 50.3% of variance in dependent variable. Conclusion: This study concluded that radiation protective environment in operating room is important to promote radiation protective behaviors and radiation safety management program to enhance self-efficacy is highly recommended.

• KIEE International Transactions on Power Engineering
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• v.3A no.1
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• pp.7-16
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• 2003

A new method to evaluate the protection capability of distribution systems is reported in this paper. This work describes the fuzzy evaluation attributes and aggregation method of evaluation results based on a hierarchical model and the modified combination rule. An evaluation grade index called "protectability" is proposed and is expected to be a very uscful tool in defining an optimal protection and realizing the adaptive protection.rotection.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.293-298
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• 2003

The rockfall protection fences are installed to reduce rockfall damage in roads side slopes. The energy absorbing capacity of widely used rockfall protection fences is about 50kJ, But in many cases, rockfall protection fences are easily damaged even by a low level of rockfall energy. The objective of this paper is to verify the energy absorbing capacity of rockfall protection fences and investigate the behavior of them by rockfall. The LS-DYNA3D, a finite elements analysis program for dynamic movement of three dimensional objects, is used to perform the numerical simulations. In the result it is shown that rockfall protection fences absorb half of standard absorbing energy or less than it. It is inadquate for the rockfall protection fences to perform the principal function. To improve the performance of the fences, new rockfall proctection fence is proposed and numerical simulation is performed.

• Journal of the Society of Disaster Information
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• v.5 no.1
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• pp.66-74
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• 2009

As building heights increase, so do these challenges in Korea. High-rise buildings present a variety of challenges to fire safety and protection. The fire protection technology in our country is still on a weak situation which is mainly due to the lack of concerns by the government, companies and citizen. This paper provides general guidance regarding fire-related property protection system for high-rise building performance based design. The importance of high-rise building in of the number of occupants, the value of property, and the a catastrophic loss would have on the community all warrant an increased level of protection and life safety. Because, We have to prepare a new spacial code and standard guidance for fire protection at the stage of the high-rise building design.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.461-466
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• 2003

The rockfall protection fences are installed to reduce rockfall damage in roads side slopes. The energy absorbing capacity of widely used rockfall protection fences is about 50kJ. But in many cases, rockfall protection fences are easily damaged even by a low level of rockfall energy. The objective of this paper is to verify the energy absorbing capacity of rockfall protection fences and investigate the behavior of them by rockfall. The LS-DYNA3D, a finite elements analysis program for dynamic movement of three dimensional objects, is used to perform the numerical simulations In the result, it is shown that rockfall protection fences absorb half of standard absorbing energy or less than it. It is inadquate for the rockfall protection fences to perform the principal function. To improve the performance of the fences, new rockfall proctection fence is proposed and numerical simulation is performed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6161-6164
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• 2014

Background: We have reported the radiation could activate STAT3, which subsequently promotes the invasion of A549 cells. We here explored the dose- and time-response of STAT3 to radiation and the effect of radiation on upstream signaling molecules. Materials and Methods: A549 cells were irradiated with different doses of ${\gamma}$-rays. The expression of and nucleus translocation of p-STAT3 in A549 cells were detected by immunoblotting and immunofluorescence, respectively. The level of phosphorylated EGFR was also assessed by immunoblotting, and IL-6 expression was detected by real time PCR and ELISA. Results: Radiation promoted the phosphorylation of STAT3 at Y705 in a dose- and time-dependent manner and nuclear translocation. The level of phosphorylated EGFR in A549 cells increased after radiation. In additional, the mRNA and protein levels of IL-6 in A549 cells were also up regulated by radiation. Conclusions: STAT3 is activated by radiation in a dose-and time-dependent manner, probably due to radiation-induced activation of EGFR or secretion of IL-6 in A549 cells.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.3
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• pp.349-355
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• 2019

In the trend of continuously increasing collection and use of personal information, there are legal grounds for protecting personal information and various policies and systems are implemented, but there is insufficient analysis about education and its effect of personal information protection. In this study, we surveyed and analyzed the degree of awareness and actual perception level in the protection of personal information of college students, and investigated the satisfaction of personal information protection education. The results of the analysis showed that students' interest in privacy protection and concern about personal information exposure was very high, but the efforts to protect personal information and the perception level of rights and systems for protecting personal information was very low. In addition, the experience and satisfaction of education for personal information protection were found to be very low. Students felt that the necessity of education for personal information protection was strongly agreed and preferred regular and continuous education rather than one-time education.

• Convergence Security Journal
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• v.12 no.4
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• pp.25-31
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• 2012

The SSE-CMM model is how to verify the level of information protection as a process-centric information security products, systems and services to develop the ability to assess the organization's development. The CMM is a model for software developers the ability to assess the development of the entire organization, improving the model's maturity level measuring. However, this method of security engineering process improvement and the ability to asses s the individual rather than organizational level to evaluate the ability of the processes are stopped. In this research project based on their existing research information from the technical point of view is to define the maturity level of protection. How to diagnose an information security vulnerabilities, technical security system, verification, and implementation of technical security shall consist of diagnostic status. The proposed methodology, the scope of the work place and the current state of information systems at the level of vulnerability, status, information protection are implemented to assess the level of satisfaction and function. It is possible that measures to improve information security evaluation based on established reference model as a basis for improving information security by utilizing leverage.