• Molecules and Cells
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• v.25 no.2
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• pp.224-230
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• 2008

Ceramides are well-known second messengers that induce apoptosis in various kinds of cancer cells, and their effects are closely related to radiation sensitivity. Phytoceramides, the yeast counterparts of the mammalian ceramides, are also reported to induce apoptosis. We investigated the effect of a novel ceramide derivative, N-acetylphytosphingosine (NAPS), on the radiosensitivity of NCI-H460 human lung carcinoma cells and its differential cytotoxicity in tumor and normal cells. The combination of NAPS with radiation significantly increased clonogenic cell death and caspase-dependent apoptosis. The combined treatment greatly increased Bax expression and Bid cleavage, but not Bcl-2 expression. However, there was no effect on radiosensitivity and apoptosis in BEAS2B cells, which derive from normal human bronchial epithelium. Cell proliferation and DNA synthesis were significantly inhibited by NAPS in both NCI-H460 and BEAS2B cells, but only the BEAS2B cells recovered by 48h after removal of the NAPS. Furthermore, the NCI-H460 cells underwent more DNA fragmentation than the BEAS2B cells in response to NAPS. Our results indicate that NAPS may be a potential radiosensitizing agent with differential effects on tumor vs. normal cells.

• Journal of Radiation Protection and Research
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• v.19 no.2
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• pp.97-98
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• 1994

• Journal of Radiation Protection and Research
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• v.20 no.3
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• pp.169-179
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• 1995

• Journal of Advanced Navigation Technology
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• v.23 no.5
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• pp.444-451
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• 2019

In this paper, we introduce the design consideration of the EMI and lightning induced transient protection circuit for RS-170a video signal on the avionics equipment. Avionics equipment is subject to the risk of malfunction or physical damage due to indirect lightning effect from lightning strike or electromagnetic interference from external environment. So in order to protect the avionics equipment from these effects, we should analyze the effect of electromagnetic interference and lightning strike on aircraft and apply protection design for each avionics device, but protection circuit may cause signal distortion if signal level is low and frequency is high. In this paper, we introduce common protection design for EMI and indirect lightning effect, and consideration for minimize signal distortion caused by protection circuit for RS-170a. In addition, we show some example of improvements to the actual equipment design using consideration discussed in this paper.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.87-92
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• 2001

Reinforced concrete have defect in durability due to carbonation, freezing and thawing, and penetration of chloride ions with time in spite of superb structure. Especially steel corrosion in concrete due to penetration of chloride ions have result in a marked decline in service life. The principal purpose in this study is to see effect of sacrificial anode cathodic system, one of the electrochemical methods in order to the control of steel corrosion in concrete. There are chloride content in concrete in cracked and no cracked specimen with cathodic protection. To recognize the effect of sacrificial anode cathodic protection, Instant-off potential are measured. We have the excellent effect for control steel corrosion adaption sacrificial anode cathodic system.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1483-1490
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• 2011

The protection effect of a $ZrO_2$ coating layer on a $LiCoO_2$ thin film was characterized. A wide and smooth $LiCoO_2$ thin film offers sufficient opportunity for careful observation of the reaction at the interface between cathode (coated and uncoated) and electrolyte. The formation of a $ZrO_2$ coating on a $LiCoO_2$ thin film was confirmed by secondary ion mass spectrometry. Scanning electron and atomic force microscopy were used to characterize the surface morphologies of coated and uncoated films before and after cycling. A $ZrO_2$-coated $LiCoO_2$ film showed a higher discharge capacity and rate capability than an uncoated film. This may be associated with a surface protection effect of the coating. The surface of a pristine film was damaged during cycling, whereas the coated film maintained a relatively clear surface under the same measurement conditions. This result clearly demonstrates the protection effect of a $ZrO_2$ coating on a $LiCoO_2$ thin film.

• Journal of Korean society of Dental Hygiene
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• v.22 no.5
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• pp.443-450
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• 2022

Objectives: This study was conducted to investigate the effect of professional self-concept and ethical awareness of dental hygiene (department) students attending a university located in Gwangju and Jeollanam-do on patients' willingness to protect personal information. Methods: Professional self-concept, ethical disposition, and patients' personal information protection intention according to general characteristics were analyzed using t-tests and one-way ANOVA. After confirming the correlation through Pearson's correlation analysis, the effect on the patient's personal information protection intention was confirmed using multiple regression analysis. Results: Professional self-concept, ethical disposition, and the patients' willingness to protect personal information all showed positive correlations. The higher the communication skills of professional self-concept and the higher the idealism of ethical orientation, the higher the patients' willingness to protect personal information. Conclusions: This study, ascertained the effect of dental hygiene students' professional self-concept and ethical consciousness on patients' personal information protection practices. The results suggest that it is necessary to develop an educational program that can enhance the practice of dental hygienists to protect patients' personal information, and to develop and conduct continuous policy development and research.

• Journal of Families and Better Life
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• v.24 no.6 s.84
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• pp.95-116
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• 2006

The purpose of this study was to validate a hypothetical path model of maternal childhood attachment, emotions, parenting behaviors, and child behavioral problems. The research was conducted with 240 sets or mothers and their children 70 mother-child teams from seven counseling organizations including the Children's Counseling Clinic, Community Social Welfare Service Center, and Welfare Service Center for the Disabled in Seoul, Incheon, and Pyeongtaek, and 170 elementary school children from Seoul and their mothers. Consequently, a total of 200 mother-child teams were selected for this study. The data in this study were analyzed with SPSS 12.0 program and LISREL 8.3 program. The result of this study is as follows: (1) Examining the path of paternal attachment and the internalizing and externalizing behavioral problems, it was noted that paternal attachment had the indirect effect of anxiety and over-protection on the path to internalizing problems and the indirect effect of anxiety also noted is that there is a full-mediation of anxiety and over-protection between paternal attachment and the internalizing problems. (2) Examining the path of maternal attachment and the internalizing problems, it was noted that maternal attachment has direct effect on the internalizing problems. Maternal attachment has the indirect effect of self-esteem depression, anxiety and over-protection on the Path, and the indirect effect of self-esteem, anxiety and over-protection. (3) Examining the path of maternal attachment and the externalizing problems, it was noted that maternal attachment has direct effect on the externalizing problems and on the path to the externalizing problems, and maternal attachment has the indirect effect of depression, the indirect effect of self-esteem and authoritarian control, and the indirect effect of self-esteem and depression.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.6
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• pp.91-98
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• 2014

For the purpose of designing and applying the optimum surge protection scheme, multi-stage coordinated surge protective device(SPD) system is suitable to successfully fulfill its tasks; first, to divert a large amount of the transient energy, second, to clamp the overvoltage to the level below the withstand impulse voltage of the equipment to be protected. The length of SPD connecting leads shall be as short as possible. Long connecting leads will degrade the protection effect of SPDs. In this paper, the influences of the length of connecting leads on the energy sharing in a coordinated SPD system were investigated experimentally, and the simulation of determining the energy sharing and protection voltage level of each SPD depending on the length of connecting leads was carried out by using P-spice program. It was confirmed that the protection voltage level and energy sharing in coordinated SPD systems are strongly influenced by the length of connecting leads.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.11a
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• pp.78-81
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• 2010

In this paper, we propose an efficient and effective selective protection scheme to SVC that exploit the propagation of protection effect by protecting significant frames that can give the maximum visual quality degradation. We model SVC dependency coding structure as a directed acyclic graph which is characterized with an estimated visual quality value as the attribute at each node. The estimated visual quality is calculated by using our model based on the proportions of intra- and inter-predicted MBs, amounts of residual, and estimated visual quality of reference frames. The proposed selective protection scheme traverses the graph to find optimal protection paths that can give maximum visual quality degradation. Experimental results show that the proposed selective protection scheme reduces the required number of frames to be protected by 46.02% compared to the whole protection scheme and 27.56% compared to the layered protection scheme.