• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.12
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• pp.9-16
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• 2011

Most of the current mobility management protocols such as MIPv4/6 and its variants standardized by the IETF do not support global seamless handover. This is because they require comprehensive changes of the existing network infrastructure. In this article, we propose a simple mobility management protocol (SMMP) which can support global seamless handover between homogeneous or heterogeneous wireless networks. The idea is that the SMMP employs separate location management function as done in SIP to support global user and service mobility. In addition, the bidirectional tunnels are dynamically constructed to support seamless IP mobility by extending the IEEE 802.21 MIH standards. The detailed architecture and functions of the SMMP have been designed. Finally, the simulation results, using NS-2, show that the proposed SMMP outperforms the existing MIPv6 and HMIPv6 in terms of handover latency, packet loss, pear signal noise ratio (PSNR).

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.201-214
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• 2005

We have designed and developed novel luminescent lanthanide complexes for advanced photonics applications. Lanthanide(III) ions (Ln$^{3+}$) were encapsulated by the luminescent ligands such as metalloporphyrins and naphthalenes. The energy levels of the luminescent ligands were tailored to maintain the effective energy transfer process from luminescent ligands to Ln$^{3+}$ ions for getting a higher optical amplification gain. Also, key parameters for emission enhancement and efficient energy transfer pathways for the sensitization of Ln$^{3+}$ ions by luminescent ligands were investigated. Furthermore, to enhance the optophysical properties of novel luminescent Ln$^{3+}$ complexes, aryl ether-functionalized dendrons as photon antennas have been incorporated into luminescent Ln$^{3+}$ complexes, yielding novel Ln(III)-cored dendrimer complex. The novel Ln(III)-cored dendrimer complex has much higher PL intensity than the corresponding simple complex, due to the efficient site-isolation effect. In this article, we will deal with recent progress in the synthesis and photophysical studies of inert and stable luminescent Ln$^{3+}$ complexes for advanced photonics applications. Also, our review will include the exploratory investigation of the key parameters for emission enhancement and the effective energy transfer pathways from luminescent ligands to Ln$^{3+}$ ions with Ln(III)-chelated prototype complexes.

• Elastomers and Composites
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• v.47 no.1
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• pp.23-29
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• 2012

The silica-silica interaction parameter (${\alpha}_F$) of the silane treated silica filled natural rubber (NR) compound was investigated. As silane (TESPT) concentration increased from 2 to 12% (2, 4, 6, 8, 10, 12%), the ${\alpha}_F$ value increased at the same silica concentration (10, 20, 30, and 40 phr). It seemed the sulfur atoms in TESPT acted as a crosslinking agent in the compound. As silica concentration increased from 10 to 40 phr, the ${\alpha}_F$ value increased at the same silane concentration due to increased silica-silica interaction.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.34.1-34.1
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• 2017

The GMT-Consortium Large Earth Finder (G-CLEF) is the very first light instrument of the Giant Magellan Telescope (GMT). The instrument is a fiber feed, optical band echelle spectrograph that is capable of extremely precise radial velocity measurement, and has been being developed through the international consortium consisted of five astronomical institutes including Smithsonian Astrophysical Observatory (SAO), Observatories of the Carnegie Institution of Washington (OCIW), and Korea Astronomy and Space Science Institute (KASI). The Preliminary Design Review (PDR) for the G-CLEF was held in Cambridge, Massachusetts in April 2015. It is scheduled to have Critical Design Review (CDR) in March 2018. Flexure Control Camera (FCC) is one of the KASI's major contributions to the G-CLEF project. In this presentation, we describe the current critical design status, and structural and thermo-elastic analyses results on the G-CLEF FCC.

• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.71-81
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• 2013

This study was executed to give a help in planning and implementing online learning. For this purpose this study investigated the effect of contents presentation types, levels and metacognition on concept map composition and learning process in online learning. Learning contents types were two, meaning-centered or context-centered. Contents levels were divided into two; basic or deficient. Metacognition was divided into two levels according to the scores of scale. Results showed that meaning-centered type(M=45.00, SE=1.97) got better scores in concept map than context-centered(M=34.71, SE=1.98), Presentation levels and metacognition had no significant influence on concept map. There were interaction effect(F=.002, p>.05) between presentation levels and metacogntion levels. The upper group in metacognition got higher score in deficient types whereas the lower group got higher score in basic type. In online learning process, learner's metacognition was an important factor to complement the contents' defect and lack.

• Korean Journal of Adult Nursing
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• v.28 no.4
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• pp.459-469
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• 2016

Purpose: This comparative descriptive study was to identify gender differences in delay seeking treatment and related experiences in patients with acute myocardial infarction (AMI). Methods: Ninety-seven participants were recruited from a tertiary hospital. Results: Mean age of 47 women was $71.5{\pm}13.3$ while that of men was $55.0{\pm}10.9$ (p<.001). More women lived alone and were jobless, less educated, and poorer than men. Men were likely to be 'current smokers' and drink alcohol, however viewed themselves healthier than women (p=.030). Women's hospital stay was $9.23{\pm}21.04$ days while men's was $4.86{\pm}2.72$ days (p=.014). More women had been diagnosed with hypertension (p=.040). Women appeared to report significantly less pain ($6.46{\pm}3.1$) than men ($8.44{\pm}1.8$). More men described their pain as sudden onset (p=.015) and chest pain as major symptom (p=.034) than women. More women were found alone upon onset of symptoms (p=.023) and had important reasons for delay seeking treatment (p=.021) than men. Median time from onset of symptoms to seeking medical service was 1.5 hours for men and 5.1 hours for women (p=.003). Median time taken from onset of symptoms to hospital for therapy was 3.5 hours for men and 9.1 hours for women (p=.019). Conclusion: This study findings that women reported less pain and delayed in seeking treatment, suggest needs for strategies targeting women at risk of AMI.

• Korean Journal of Adult Nursing
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• v.22 no.1
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• pp.60-69
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• 2010

Purpose: The aim of this study was to investigate the level of resilience and related factors in patients with Parkinson's disease (PD) in Korea. Methods: Data were obtained from 148 patients using the Resilience Scale (RS), Beck's Depression Inventory (BDI), and Spielberger's Anxiety Inventory (AI). Results: The mean scores of the RS, BDI, and AI were $127.7{\pm}21.6$, $12.9{\pm}9.3$, and $41.9{\pm}11.1$, respectively. The RS score was strongly correlated with the BDI score (r=-.531, p<.001) and the AI (r=-.572, p<.001). The resilience was significantly revealed by household income (F=4.002, p=.009) and presence of a hobby (t=-3.300, p=.001). In addition, resilience was significantly correlated with age of disease onset (r=.164, p=.046), years of living with PD (r=-.262, p=.001), and the length of treatment with levodopa (r=-.283, p<.001). From the stepwise multiple regression analysis, the most important factors related to the RS score were the AI score, household income, and length of treatment with levodopa. Conclusion: Understanding these factors is essential for developing effective interventions to improve resilience in patients with PD.

• Korean Journal of Adult Nursing
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• v.28 no.6
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• pp.701-708
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• 2016

Purpose: This study investigated Korean women in between age 30 to 60 who were obese or overweight in order to explore their self-perception based on lifetime phase. Methods: Focus group interviews were performed four times with six to eight participants in each group (a total of 27). Data were analyzed using inductive thematic analysis. Results: The data analysis from the interviews revealed recurring common themes: heavy heart, heavy body, resigned acceptance of their own condition, and compromise. The study also found that each age group had different concerns: concerning others' gaze on their obese appearances (30s), realizing their aging obese appearances (40s), recognizing red flags of their health with obesity (50s), and becoming ambivalent about their obese appearances (60s). Overall, their perceptions of being overweight were negative and stressful. Women in their 30s and 40s were more interested in their appearances, and thus were more obsessive about weight gain. In contrast, women in their 50s and 60s were more accepting of their physical appearances, and thus were more concerned about living healthy than losing weight. Conclusion: These results may be useful to consider when developing tailored weight-control programs for obese and overweight Korean women. Additionally, strategic approaches for successful and effective programs targeting healthy weight should be based on better understanding about women's self-perceptions and motivations.

• Journal of Korean Academy of Nursing
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• v.41 no.5
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• pp.663-672
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• 2011

Purpose: Purpose of this study was to investigate the status of depression in academic high school students and path analysis model for exploring the mediating role of entrapment to depression in relation to academic stress and perceived social support. Methods: Measurements were four reliable questionnaires measuring academic stress, social support, entrapment, and depression. Data were collected from students in 17 high schools in Seoul. Results: Students (n=5,346) completing the questionnaires indicated depression & entrapment from academic stress. Depression was more prevalent in girls, those whose parents' household income was less than two million won, who did not live with father or mother or both due to divorce, separation, or death, and those who smoked or used alcohol. Entrapment was more prevalent in students similar to cases of depression and in seniors. According to the proposed path model, 48.6% of depression was explained by academic stress, social support, and entrapment. The indirect effect of entrapment as a mediator between academic stress and depression was verified and larger than the direct effect of academic stress on depression. Conclusion: Considering levels of depression and entrapment demonstrated by these students, better mental health programs with diverse strategies should be developed for their psychological well-being.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.1
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• pp.27-38
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• 1995

The organ or tissue doses were determined with head and neck phantom measurement for multiple axial scans (36 slices), multiple coronal scans (13 slices), 3 types of single axial scans(orbit, maxillary sinus and mandibular canal) and single coronal scan (maxillary sinus). For each scan sequence 30 TLDs were placed in selected sites(16 internal sites and 14 external sites) in a tissue-equivalent phantom. The exposure was made at 120kVp, 500mAs with 5 mm slice width. The results were as follows : 1. In multiple axial scans, the greatest effective dose recorded was that delivered to the thyroid glands(2.77 mSv) and the least was that received by the skin(0.05 mSv). From these data, stochastic effects were 202.2x10/sup -6/ and 3.7×10/sup -6/, respectively. 2. In multiple coronal scans, the greatest effective dose recorded was that delivered to the salivary glands(0.58 mSv) and the least was that received by the skin(0.01 mSv). From these data, stochastic effects were 42.2×10/sup -6/ and 0.7×10/sup -6/, repectively. 3. Among single axial scans, the greatest effective dose recorded was that delivered to the salivary gland(0.38 mSv) in maxillary sinus scan. From this data, stochastic effect was 27.7×10/sup -6/. 4. In single coronal scan, the greatest effective dose recorded was that delivered to the salivary gland(0.01 mSv). From this data, stochastic effect was 1.0×10/sup -6/. 5. The equivalent dose measured that delivered to the lens of the eyes was 69.64 mSv in multiple axial scan, 39.32 mSv in multiple coronal scan and 36.77 mSv in single axial scan(orbit).