• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.12
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• pp.1846-1854
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• 2022

The sophistication and diversification of mission equipment for surveillance and reconnaissance is leading to a demand for large-capacity public data links. Overseas, a T4 class(274Mbps) common data link was applied to the Global hwak, a high-altitude unmanned aerial vehicle, and various research and development are being conducted in Korea. In this paper, we propose a structure in which pilot is additionally applied to improve SNR performance while minimizing data transmission rate loss in the DVB-S2 frame structure, which is a european satellite broadcasting standard, for high-capacity transmission of T4 class or higher in the common data link. For the performance evaluation of the proposed structure, the performance of the DVB-S2 was compared and analyzed by simulating the UAV data link channel environment. As a result of simulation, 0.15% of transmission rate loss occurred at T4 class transmission rate compared to DVB-S2 in the proposed structure, but improved SNR reception performance of 0.2~0.3dB was confirmed in the UAV channel environment.

• Journal of Periodontal and Implant Science
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• v.37 no.3
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• pp.479-488
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• 2007

In spite of the attention given to the study of mesenchymal stem cells derived periodontal ligament (PDL), there is a lack of information about canine PDL cells. In this study, we characterized canine PDL cells to clarify their stem cell properties, including self renewal, proliferate rate, stem cell markers and multipotency. PDL cells were obtained from extracted premolars of canines, following a colony forming assay and proliferation rate of sub-confluent cultures of cells for self-renewal, immunostaining for STRO-1 and CD146/MUC18 and a differentiation assay for multipotency. Canine PDL cells formed single-cells colonies and 25% of the PDL cells displayed positive staining for BrdU. The cells expressed the mesenchymal stem-cell markers, STRO-1 and CD146/MUC18. Under defined culture conditions, the cells differentiated into osteoblasts and adipocytes, but the cells didn't differentiated into chondrocytes. The findings of this study indicated that the canine PDL cells possess crucial stem cells properties, such as self-renewal and multipotency, and express the mesenchymal stem cell markers on their surface. The isolation and characterization of canine PDL cells makes it feasible to pursue preclinical models of periodontal regeneration in canine.

• Journal of IKEEE
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• v.19 no.3
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• pp.371-377
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• 2015

This paper is about the RF transceiver designed and implementation for common data link. The trasmitter is configured as a frequency up-converter, a power amplifier and a duplexer. The receiver is configured as a duplxer, a frequency down-converter and a low noise amplifier. The maximum transmission distance, the reception sensitivity is designed to meet the electrical and temperature characteristics and the like. Using a modeling and simulation in order to meet the requirements of the RF transceiver has been designed and implemented. Transmitting output power and Noise Figure has been measured with 38.58dBm and 5.5dB, respectively. All of the electrical and temperature specifications was meet. Was confirmed all of the requirement specification by electrical characteristics test and temperature characteristics test.

• Journal of the Korea Society of Computer and Information
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• v.22 no.8
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• pp.63-72
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• 2017

In this paper, we propose a security architecture for HDLC-based T4 class common data link. The common data links are composed of point-to-point, multi-to-point, and point-to-multi mode. For multi-to-point mode, one node has a bundle of point-to-point links with different end-point on the other side of the links. Thus multi-to-point mode can be considered as a bundle of point-to-point mode. Point-to-multi mode is broadcasting link. For point-to-point mode we adopted robust security network scheme to establish a secure data link, and for multi-to-point mode we use broadcast encryption scheme based on ID-based cryptography to distribute encryption key for broadcasting message encryption. We also included MACsec technology for point-to-point data link security. Computational and communicational complexity analysis on the broadcast encryption have been done.

• The Mathematical Education
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• v.52 no.2
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• pp.149-161
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• 2013

This study was to focus on analyzing about the composition of storytelling in the first graders' math textbooks of the middle school, which were recently implemented. The textbooks published by three well known publishing companies were chosen and three graduate students had scored the frequency of the problems according to three types of storytelling. As the results, in areas of mathematics, Number & Operation(44.23%), Letters & Formula(44.53%), Function(46.53%), Probability(41.67%), Geometry(46.23%) showed to have storytelling in balance. The type of 'explosion of mathematical history(EMH)' was shown in geometry most, the type of 'connection to daily life(CDL)' in statistics most, and the type of integration of disciplines(ID)' in geometry most in 5 math areas. Among three types of storytelling, the type of EMH was shown fewer that other 2 types. If we develop more problems in this type, students would study mathematics in-depth according to Freudenthal's principle of historical reinvention.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.227-241
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• 2005

Objective & Methods : The purpose of this study is to observe the effects of Asari Herba Cum Radice herbal-acupuncture solution(AHCR-HAS) on arthritis of mice induced by Collagen II at Joksamni(ST36). The author performed several experimental items. First, it is the cell survival rate of mice lung fibroblasts and expression of TNF-${\alpha}$ in synovial cells. Second, it is the incidence rate of arthritis and the weight of spleen. Third, it is the levels of IL-6, TNF-${\alpha}$, INF-${\gamma}$, IgG, IgM and anti-collagen II in serum Fourth, it is histological analysis of the mice joint. Fifth, it is expression ratio of CD3e+ to CDl9+ cell, CD4+ to CD8+ cell, CD69+/CD3e+ cells, CD11+/CD19+ cells and CD11b+/Gr-1+ cells. Result : 1. The highest survival rate of mice lung fibroblasts were measured in the 1% AHCR-HAS, and the expression of TNF-${\alpha}$ in synovial cells were significantly decreased in the 1% AHCR-HAS. 2. In the AHCR-HA I & AHCR-HAII groups, the incidence of arthritis and the weight of spleen were significantly decreased. 3. In AHCR-HAI & AHCR-HAII groups, the levels of IL-6, INF-${\gamma}$, TNF-${\alpha}$, IgG, IgM and anti-collagen II in serum of CIA mice were significantly decreased. 4. In histology, the cartilage destruction and synovial cell proliferation were decreased in the AHCR-HA I & AHCR-HAII groups, and the collagen fiber expressions in the AHCR-HA I & AHCR-HAII groups were similar with that of the Normal group. 5. In the AHCR-HA I & AHCR-HA II groups, the expression ratio of CD3e+ to CD19+ cell and CD4+ to CD8+ cell were similarly maintained as Normal group in lymph nodes, and CD69+/CD3e+ cells and CD11a+/CD19+ cells were decreased in Iymph nodes, and CD11b+/Gr-1+ cells were decreased in synovium. Conclusion : Taking all these observations into account, AHCR-HA is considered to be effective in prophylaxis and treatment of rheumatoid arthritis, and then more effective in prophylaxis than treatment, so put to practical use in future rheumatoid arthritis clinic.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.21-30
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• 2020

In this paper, we predicted the propagation loss for the air-to-ground (A2G) channel between the ground control system and the unmanned aerial vehicle (UAV) using the prediction model for the aircraft recommended by the International Telecommunication Union (ITU). We analyzed the network coverage of the aerial relay system based on the medium altitude UAVs by expanding it into the air-to-air (A2A) channel. Climate and geographic factors in Korea were used to predict propagation loss due to atmospheres. We used the measured data published by the Telecommunication Technology Association (TTA) for regional rainfall-rate and effective earth radius factors to increase accuracy. In addition, the aerial relay communication system used the key parameter of the common data link (CDL) system developed in Korea recently. Prediction results show that the network coverage of the aerial relay system broadens at higher altitude.

• The Transactions of the Korea Information Processing Society
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• v.7 no.12
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• pp.3840-3847
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• 2000

Electronic Industries Association has set a standard format called CDIF(CASE Data Interchange Format) for exchanging information between CASE tools from 1991. If data used on a CASE tool is represented in CDIF format, then any other CASE tools can use the data by translating CDlF format into their own format. In order to do so, each CASE vendor must provide a translator program from CDIF to its own data format or from its own data to CDIF format. In this thesis, we have implemented a source code generator for translating CASE data format into CDIF format only if they provide how data is stored. This automatic program generator generates CDIF statements using data format used in CASE tools, meta information about stored data and CDIF meta information. In the thesis, the automatic program generator has been implemented with Java and Oracle DBMS with JOBC interface in Sun O/S environment.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.254-254
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• 1996

Eosinophils are known to be important effector cells in pathogenesis of asthma. The elucidation of mechanism by which eosinophil survival is regulated in vivo at sites of inflammation is critical tn our understanding of asthma pathogenesis. The maintenance of these cells at site of inflammation depends upon tile balance between its tendency to undergo apoptosis and tile local eosinophil-viability enhancing activity, Qualitative and quantative phenotypic differences have been observed between bronchoalveolar lavage (BAL) and peripheral blood (PB) eosinophils (EOS). We hypothesize that BAL EOS Possess altered functional feature compared to PB EOS. BAL and PB EOS were obtained from ragweed allergic asthmatics after segmental antigen challenge (SAC) at 24 hour or one week, and purified over percoll and CDl6 negative selection. Cells were cultured in duplicate in RPMI, 15% FCS and 1% penicillin/streptomycin without exogenous cytokines. Eosinophil purity and viability was >92%. BAL. EOS viability was 69${\pm}$4.4% versus 39${\pm}$1.6% for PB EOS (p<0.005) at 48 hour time point, and this difference was maintained through day 5 (32${\pm}$7.6% vs. 3.0${\pm}$ 1.4%, p<0.05), Among BAL EOS, those harvested one week after SAC appeared to have an prolonged survival compared to those harvested at 24 hour. Coculture of BAL and PB EOS resulted in significant viability enhancement than expecteed. Direct neutralization of GM-CSF activity, not IL-3 and EL-5, markedly decreased tile survival of BAL EOS in culture, and abrogated tile viability enhancing activity of their culture supernatants in a dose dependent manner. We conclude that BAL EOS activated in vivo possess enhanced viability compared to PB EOS. Mixing and neutralization experiments suggest a role for autocrine production of GM-CSF.

• Journal of Chest Surgery
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• v.38 no.7 s.252
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• pp.514-517
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• 2005

Gastrointestinal stromal tumor is documented on every part of the gastrointestinal tract. It develops in the stomach and the small intestine most commonly, and also in the esophagus. A 44 year-old male patient was admitted due to dysphagia and weight loss. Chest CT showed about $15\times11\times11cm$ sized, well-defined, and lobulated soft tissue mass with central necrosis was noted in the posterior wall of lower esophagus throughout the lesser curvature of upper stomach. We performed the distal esophagectomy and total gastrectomy using thoracoabdominal incision. The tumor was positive at CD117 (c-kit) and CD 34, and was diagnosed as malignant GIST of the distal esophagus and upper stomach. The patient is on routine follow up at the out patient department for nineteen months up to now.