• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.303-306
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• 2009

High temperature solid oxide fuel cells (SOFCs) offer a clean, pollution-free technology to electrochemically generate electricity at high efficiencies. Solid oxide fuel cells in several different designs have been investigated; these include planar and tubular geometries. The tubular type cell is widely researched due to it have advantages about thermal expansion and sealing issues. Unfortunately, lab scale tubular cell for testing has thermal expansion and sealing problems. The previous Jig for lab scale tubular cell testing has many sealing problems. When we feed fuel gas to jig inlet, ceramic glue sealant has amount of gas expansion pressure, because temperature of feeding gas changes ambient temperature to high temperature ($700{\sim}900^{\circ}C$). Furthermore, when we carry out long time test, something like degradation test, crack of ceramic glue sealant due to weakness of mechanical properties can make stop working the test. Additionally, we reduce setting process for assembling, because micanite is not required drying or debinding process.

• Electrical & Electronic Materials
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• v.9 no.9
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• pp.949-953
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• 1996

In this paper, the cathode materials of solid oxide fuel cell were fabricated, and the analysis of TG/DTA, XRD, thermal expansion and electric conductivity were investigated. As a result, thermal expansion coefficient of LSM was not quite different from that of electrolyte. And the performance of LSM(x=0.4) was more excellent than the others.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.39-44
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• 2013

Long Term Evolution (LTE) - Advanced has developed Heterogeneous Network (HetNet) that consists of a mix of macrocells and low-power nodes such as picocells to improve the system performance. Also, to encourage data offloading in HetNet, Cell Range Expansion (CRE) have been introduced. In this paper, we propose a cell selection scheme based on Signal to Interference plus Noise Ratio (SINR) for optimal offloading effect. And we manage the interference for user located in cell range expanded region using Almost Blank Subframe (ABS) with flexible ABS ratio to improve the spectrum efficiency in time domain. Simulation results show that proposed scheme can improve spectrum efficiency of macrocell and picocell user. Eventually, proposed scheme can imporve overall user performance.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.943-945
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• 2013

The study of Schwann cell myelination has been facilitated by the availability to isolate and establish pure population of primary Schwann cells. Dorsal root ganglia (DRG) of mouse embryo as source of Schwann cells were used in this study. This method includes three steps: first step of dissociation of the embryonic DRG, second step of expansion of Schwann cell precursors, followed by mechanical separation of the Schwann cell-neuronal network from the underlying fibroblasts, and third step of purification of Schwann cells from the associated neurons and subsequent expansion of the purified Schwann cells. We made a highly purified population of Schwann cells and Schwann cell-neuron networks in a short period using this procedure.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.475-478
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• 2001

Ex vivo hematopoietic cells can treat patients suffering from hematopoietic malignancies using bone marrow transplantation therapies. A initial cell density of $1.5{\times}10^6cells/ml$ and a growth factors of IL-3(5ng/ml), SCF(5ng/ml) and FL(25ng/ml) result in a 3.6-fold expansion of LTC- IC but a unexpansion of total cells.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.760-763
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• 2010

The expansion of 1D numerical code to 2D or 3D is needed in order to improve the analysis accuracy of the interior ballistics. The cut cell method has been imposed for the code expansion to multi dimensions. The MUSCL-Hancock scheme as a high resolution method has been selected. A feasibility of the cut cell method has been verified by analyzing the free piston problem.

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.95-96
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• 2007

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.243.1-243.1
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• 2014

For two-dimensional grid electrodes immersed in plasmas, sheath expansion due to negative high-voltage pulse applied to the electrode generates high-energy pseudowave. The high-energy pseudowave can be used as ion beam for ion implantation. To estimate ion dose due to high-energy pseudowave, investigation on sheath expansion of grid electroes is necessary. To investigate sheath expansion, an analytic model was developed by Vlasov equation and applying the 1-D sheath expansion model to 2-D. Because of lack of generalized 2-D Child-Langmuir current, model cannot give solvable equation. Instead, for a given grid electrode geometry, the model found the relations between ion distribution functions, Child-Langmuir currents, and sheath expansions. With these relations and particle-in-cell (PIC) simulations, for given grid electrode geometry, computation time was greatly reduced for various conditions such as electrode voltages, plasma densities, and ion species. The model was examined by PIC simulations and experiments, and they well agreed.

• BMB Reports
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• v.45 no.1
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• pp.51-56
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• 2012

The purpose of this study was to determine the effects of duration and timing of glucocorticoid treatment on the expansion and differentiation of porcine neonatal pancreas cell clusters (NPCCs) into ${\beta}$-cells. After transplantation of NPCCs, the ductal cyst area and ${\beta}$-cell mass in the grafts both showed positive and negative correlations with duration of dexamethasone (Dx) treatment. Pdx-1 and HNF-3${\beta}$ gene expression was significantly downregulated following Dx treatment, whereas PGC-1${\alpha}$ expression increased. Pancreatic duct cell apoptosis significantly increased following Dx treatment, whereas proliferation did not change. Altogether, transdifferentiation of porcine NPCCs into ${\beta}$-cells was influenced by the duration of Dx treatment, which might have been due to the suppression of key pancreatic transcription factors. PGC-1${\alpha}$ plays an important role in the expansion and transdifferentiation of porcine NPCCs, and the initial 2 weeks following transplantation of porcine NPCCs is a critical period in determining the final ${\beta}$-cell mass in grafts.

• The Journal of Korean Institute of Next Generation Computing
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• v.13 no.5
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• pp.104-112
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• 2017

The CRE (Cell Range Expansion) that selects the small cell with more efficient uplink resources has been developed by 3GPP to relieve the problem of the traffic imbalance due to the power differences between macro and small cells in HetNet. In addition, ABS (Almost Blank Subframes) has been proposed to resolve the signal interference problem due to the operation CREs. This paper proposes an effective method to calculate the ABS ratio by considering the proportion of the number of UEs in CRE and macro cell ranges, as well as the number of small cells in a macro cell. The proposed method has been implemented on the LTESim simulator, and compared with previously proposed methods. The experimental results show that the proposed method can improve the throughput and packet loss ratio performances. In particular, it is also shown that CRE bias values affect those performances, and there exist effective CRE bias values to derive the best performances.