• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5B
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• pp.385-394
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• 2012

The tactical mobile communication network, which comprises a part of the next-generation Tactical Information and Communication Network (TICN), provides means of communication and control for Tactical Multi-Functional Terminals (TMFT) belonging to a Mobile Subscriber Access Point (MSAP). The next-generation of MSAP is capable of constructing a backbone network via LCTR and HCTR directional antennas. At the same time, WMN modules are used to create and manage a wireless mesh backbone. When directional antennas are used in mobile environments, seamless services cannot be efficiently supported as the movement of the node prevents the angle of the antenna to constantly match. Therefore, data communication through the wireless mesh networks is required to provide direct communication between mobile MSAPs. Accordingly, mutual authentication and data encryption mechanisms are required to provide reliable data transmission in this environment. To provide efficient mutual authentication between MSAP devices, the process of verifying a certificate of the other MSAP device through its own authentication server is required. This paper proposes mutual authentication mechanisms where the MSAP requiring authentication and the MSAP that permits it initiates low-cost and efficient authentication in a distributed way. More specifically, we propose a method of applying EAP-ELS (Extensible Authentication Protocol-Transport Layer Security) in the next-generation TICN.

• Management & Information Systems Review
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• v.35 no.1
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• pp.273-286
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• 2016

This study investigated the information contents of KOSPI200 Options for intraday big market movement by using minute by minute data. The major findings are summarized as follows; First, big market movement occurred more frequently during 9:00~10:00 and 14:00~14:50. These phenomena reflect market unstability just after opening and near closing. Second, VKSOPI is most closely associated with extreme changes such as KOSPI200 jumps. Third, VKOSPI is showed more predictive power with negative KOSPI200 jumps than KOSPI200 jumps. Fourth, VKOSPI showed predictive power for the positive and negative jumps up to 30 minutes before the jumps occurs. The purpose of this study is to explore the most recent topics in the field of finance, research on market microstructure. This study is an important contribution to investigate intraday information comprehensively in terms of market microstructure effects using the 15-year long-term and the high-frequency data(minute by minute). The results of this study are expected to contribute to detect intraday true jumps, proactive development of market risk indicators, risk management, derivatives investment strategy.

• Polymer(Korea)
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• v.29 no.1
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• pp.36-40
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• 2005

Poly(amino acid) derivatives have been widely investigated as a drug carrier in drug delivery system. Particularly,polysuccinimide (PSI) is one of the most promising drug carriers since it possesses suitable physicochemical characteristics for development of macromolecular prodrugs, due to biocompatibility and biodegradability. In this study, we deal with the synthesis of polyaspartamide having various functional groups such as methoxy-poly(ethylene glycol) (MPEG) via ring closing of PSI. PSI was synthesized by polyonensation polymerization of spartic acid. The variety of average molecular weight was confirmed with reacion time and catalyst content to observe the optimum condition of synthesis. MPEG, hydrophilic chain, was bonded to fabricate polymeric micell composed of hydrophilic and hydrophobic polymer. All materials were characterized by 1H-NMR, FT-IR and GPC. In addition, the formation of nanoparticle micelle as drug carrier were also examined. Micelle size was measured by ELS and AFM. The functionalized polysparamide formed nanoparticle micelle whose size ranged from 90 to 130 nm. In conclusion, we prepared polyaspartamide functionalized with PEG examined the possibility as drug carriers.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.339-349
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• 2007

For various types of the Pungchon limestone, diverse mineral characters of the limestone including their size and morphology are investigated by using of ELS and SEM to examine the possibility of application as fillers to paper industry. Also, the measurement of zeta potential and the evaluation of coagulation properties in calcite suspension was made for fine powders of the limestone to examine the applicability and efficiency in wet-papermaking process. Fine powder of the Pungchon lime-stone, largely controlled by original mineral characters of ore in mineralogical aspects, exhibits some-what different trend in particle morphology according to ore types, and thereby, the size distribution, zeta potential and coagulation properties also become different. The examined whiteness, brightness, opacity and sheet strength in hand sheet also show remarkable differences according to ore types. These are seemed to be basically due to the results of combined effects of whiteness, site distribution, refractive index, and morphology of the limestone powder on the properties of hand sheet. Considering the investigated results, all types of the Pungchon limestone appear to be sufficiently applicable to paper industry. Especially, the mega-crystalline calcite type is evaluated to be overall suitable for the purpose of paper industry due to the higher values in whiteness and brightness. In addition the fine powder of micro-crystalline calcite type is assessed particularly to have a good quality in sheet strength by virtue of irregular particle shape.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.237-247
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• 2019

The purpose of this study was to evaluate the level and intensity of emotional labor of physical therapists and occupational therapists, and to identify the factors affecting them. Cross-sectional study was conducted on physical therapists and occupational therapists across the country using self-populated questionnaire. A total of 2,000 questionnaires were distributed to retrieve 1,500 questionnaires(75%), of which 1,374 questionnaires(68.7%) were finally analyzed, excluding 126 that answered duplicates or were missing answers. Multi-linear regression was performed to identify factors on the strength of emotional labor. According to the analysis results, high-risk groups in the areas under 'Emotional demand and regulation' and 'Overload and conflict in customer service' and 'Emotional disharmony and hurt' were 29.4%, 19.0% and 22.0% respectively, especially in 'Emotional demand and regulation', 'Overload and conflict in customer service', 'Emotional disharmony and hurt' for women working days, and 49% of daily work hours. Accordingly, we will be able to regularly screen physical therapists and occupational therapists for dangerous groups, and manage the intensity of emotional labor through the creation of a therapist's working environment, such as limiting overtime hours and assigning appropriate number of patients. Through this study, the grounds and methods for mitigating the negative effects of emotional labor and mediating emotional labor should be provided.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.35-39
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• 2010

Purpose: The aim of this study was to investigate distribution of particle size in phytate kit and compare filtered method with non-filtered method using 200 nm filter for sentinel lymphoscintigraphy (SLS). Materials and Methods: Five phytate kit of having the same available period was measured by particle size analyzer. For in-vivo experiment, $^{99m}Tc$-phytate was injected intradermally at both foot to perform lymphoscintigraphy. Imaging was acquired at 1hour after injection. Region of interest (ROI) was drawn in inguinal and background area for analysis. RAW 264.7 cells (Murine macrophage cell) were prepared for measurement of celluar uptake as a representative of macrophages. Paired t-test was performed using SPSS (SPSS Inc, USA) for statistical analysis. Results: The size of most particle in Techne phytate kit was distributed in 130~650 nm(90.5 %). In-vivo study, the ROI analysis showed similar result between filtered and non-filtered sample, and the numerical value of count/pixel were $58.3{\pm}5.97$ and $60.2{\pm}4.88$. In-vitro study, cellular uptake study also showed no difference between filtered and non-filtered sample by gamma counting. Conclusion: The present study demonstrates that there was no meaning of 200 nm filtered method for SLS using $^{99m}Tc$-phytate.