• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.127-135
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• 2020

The purpose of this paper is to classify individual startups by growth stage based on data-based quantitative criteria. This is to provide a basis for systematic support for government startups based on accurate statistics on the startup growth process. This startups were the TIPS (Tech Incubator Program for Startup) support company, which used a relatively reliable startup. We found seed money to complete MVP (Minimum Viable Product) within 1.5 years after establishment, verified PMF (Product-Market Fit) within 1 year, attracted Series A investment within 2.5 years after establishment, and successfully commercialized it. It attracted Series B investment for stable growth within 1.5 years (Series B investment within 4 years from start-up). The results of the study, the division of government programs that support stage-based startup commercialization, that is, within three years and within seven years of establishment, is significant to date. Three directions are suggested for future research. First, develop indicators for monitoring startup growth stages. Second, it continuously updates the annual changes and tracks the growth stages of individual startups. Third, we discover the successful growth law of technology-based startups by applying in-depth case analysis of successful startups to the model.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.29 no.3
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• pp.134-149
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• 2016

Objectives : Gal-Geun-Tang (GT) has been described from SANGHAN in Korean traditional medicine and known to act against cold, fever, hypertension, and nasal catarrh. However, little has yet been learned about the effect of GT on immune function. In the current study, in vitro and in vivo immunomodulatory activity of GT (water extract) was investigated.Methods : Water extract of GT induced in vitro proliferation of spleen cells and significantly increased their proliferative responses during anti-CD3 activation. Using purified splenic T and B cells, it was revealed that GT has a mitogenic activity to B cells and promotes their proliferation induced by lipopolysaccharide, whereas T cell proliferation was not triggered and GT was rather inhibitory to T cell activation caused by anti-CD3 antibody. In the presence of antigen presenting cells (APC), GT addition resulted in a significant increase of IFNγ and IL-4, but not IL-2, production. However, addition of high concentration (1,000㎍/㎖) of GT led to a marked reduction in T cell cytokine production and under such condition, GT facilitated apoptosis of T cells when examined by flow cytometry with propidium iodide staining.Results : In vivo immunomdulation of GT was also investigated using a mouse model. Following keyhole limpet hemocyanin (KLH) immunization, GT (1 ㎎/day) was orally administered for 9 days. Cell numbers in thymus, spleen and peripheral blood were not altered by GT administration, indicating that such dose is not immunotoxic. Cell numbers in draining lymph nodes (LN) and ex vivo Ag-specific proliferation of LN cells were significantly elevated by GT administration. However, any preferential stimulation of T or B and CD4⁺ or CD8⁺ T cell subpopulations was not observed in a flow cytometric analysis of LN cells. This result shows that GT does not promote in vivo B cell proliferation while GT enhances Ag-specific proliferation of LN cells, unlike what was observed in vitro.Conclusions : For a further understanding of in vivo immunomodulatory activity of GT, ex vivo cytokine production of LN cells obtained from KLH-immunized mice was evaluated. Ag-specific IFNγ production was significantly higher in GT-treated mice when compared to PBS-treated control mice. In contrast, IL-4 production in GT-treated group was comparable to control group unlike to in vitro data. In addition, GT administration did not result in any significant differences in serum levels of Ig (IgM, IgG1 and IgG2a) between GT-treated and control groups. Taken together, these data strongly support that GT promotes immune response, more profoundly type 1 helper T cell (Th1) activity and GT may be applicable for treatment of intracellular parasite infection such as viral diseases.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1183-1189
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• 2014

The accuracy of the resistive-sheet technique in calculating the RCS(Radar Cross Section) of a deciduous leaf is examined in this paper for various thicknesses and dielectric constants, and a range of thicknesses for the resistive sheet technique is proposed. At first, a leaf was assumed to be a lossy dielectric disk, and the dielectric disk was again assumed to be a resistive sheet with an appropriate resistivity for a given thickness, a dielectric constant, and a frequency. Then, the RCS of the leaf was computed using the physical optics(PO) method, and was compared with the calculation results of a numerical analysis: i.e., a commercial tool based on the FEM (Finite Element Method) technique. It was shown that the error increases as the thickness increases. The error was 0.1 dB, for example, when the thickness is 1.2 mm and 3.7 dB when the thickness is 3 mm with a dielectric constant of(21.4, 9.7) at 9.6 GHz. It was also found that the error decreases as the dielectric constant increases. This study will be very useful for calculating the scattering characteristics of numerous leaves in a vegetation canopy for estimating its radar backscatter using scattering model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.307-314
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• 2011

A new predistortion technique for dynamic spectrum allocation systems such as cognitive radio (CR) is proposed. The system model considered in this paper occupies a small band at a time, but the center frequency can be changed in the wide range of frequency. In this scenario. the front-end filter may not eliminate the harmonics of the power amplifier (PA) output. The proposed PD reduces the spectral regrowth of the fundamental signal at the carrier frequency (${\omega}_0$) and removes the harmonics ($2{\omega}_0$, $3{\omega}_0$, ...) at the same time. The proposed PD structure is composed of multiple predistorters (PDs) centered at integer multiples of ${\omega}_0$. The PD at ${\omega}_0$ is for removing spectral regrowth of the fundamental signal, and the others are for harmonic reduction. In the proposed PD structure, parameters of PDs are found jointly. Simulation results show that the spectral regrowth can be reduced by 20dB, and the 2nd and 3rd harmonics can be reduced down to -70dB from the power of the fundamental signal.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.53-56
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• 1998

Electroluminescent(EL) devices based on organic materials have been of great interest due to their possible applications for large-area flat-panel displays, where they are attractive because of their capability of multicolor emission, and low operation voltage. In this study, glass substrate/ITO/Eu(TTA)$_3$(Phen)/Al(A), glass substrate/ITO/TPD/Eu(TTA)$_3$(p-hen)/Al(B) and glass substrate/ITO/TPD/Eu(TTA)$_3$(phen)/AlQ$_3$/Al(C) structures were fabricated by vacuum evaporation method. where aromatic diamine(TPD) was used as a hole transporting material, Eu(TTA)$_3$(phen) as an emitting material. and tris(8-hydroxyquinoline)Aluminum(AlQ$_3$) as an electron transporting layer. Electroluminescent(EL) and I-V characteristics of Eu(TTA)$_3$(Phen) with a various thickness were investigated. This structure shows the red EL spectrum, which is almost the same as the PL spectrum of Eu(TTA)$_3$(phen). I-V characteristics of this structure show that turn-on voltage was 9V and current density was 0.01A/$\textrm{cm}^2$ at a dc operation voltage of 9V. Electrical transporting phenomena of these structures was explained using the trapped- charge-limited current model with I-V characteristics.

• Food Science of Animal Resources
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• v.42 no.6
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• pp.1046-1060
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• 2022

This study aimed to investigate the effects of the metabolites of Latilactobacillus curvatus BYB3 and indole-activated aryl hydrocarbon receptor (AhR) to increase the tight junction (TJ) proteins in an in vitro model of intestinal inflammation. In a Western blot assay, the metabolites of L. curvatus BYB3 reduced the TJ demage in lipoploysaccharide (LPS) stimulated-Caco-2 cells. This reduction was a result of upregulating the expression of TJ-associated proteins and suppressing the nuclear factor-κB signaling. Immunofluorescence images consistently revealed that LPS disrupted and reduced the expression of TJ proteins, while the metabolites of L. curvatus BYB3 and indole reversed these alterations. The protective effects of L. curvatus BYB3 were observed on the intestinal barrier function when measuring transepithelial electrical resistance. Using high-performance liquid chromatography analysis the metabolites, the indole-3-latic acid and indole-3-acetamide concentrations were found to be 1.73±0.27 mg/L and 0.51±0.39 mg/L, respectively. These findings indicate that the metabolites of L. curvatus BYB3 have increasing mRNA expressions of cytochrome P450 1A1 (CYP1A1) and AhR, and may thus be applicable for therapy of various inflammatory gut diseases as postbiotics.

• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.170-177
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• 2005

This study was conducted in order to assess whether the form of the shade guide affects in deciding the color of the teeth using the shade guide Eight shade light cured composite resins (Esthet-X, Dentsply, Milford, USA) were used in this study. Shade guides including the model of maxillary central incisors, teeth-form shade guide, doughnut form shade guide, and shade guide with perforated gray shield were prepared with eight shade composite resins and provided the codes randomly After arranging the models of teeth, 19 dentists working at the clinic of the Dentistry of Chonnam University Hospital and 65 students of college of dentistry, Chonnnam University selected the shade guides corresponding to the color of each tooth on the gray board under the D$_{65}$ standard illuminant. Bl shade showed highest accuracy of about 95% among all shade guides of 3 forms applied to the test and regardless of observer, tooth form shade guide showed the highest accuracy (p < 0.05) , and the doughnut form showed the lowest accuracy (p < 0.05). At the time of deciding on the color of the teeth using the shade guides as a result of above, the forms of the shade guides can affect the accuracy, and it suggests that the development of the diversified forms of shade guides, which may obtain more accurate results, is required.

• Restorative Dentistry and Endodontics
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• v.31 no.5
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• pp.359-370
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• 2006

The objective of this study was to investigate the effect of excessive occlusal loading on stress distribution on four type of cervical lesion, using a three dimensional finite element analysis (3D FEA). The extracted maxillary second premolar was scanned serially with Micro-CT. The 3D images were processed by 3D-DOCTOR. ANSYS was used to mesh and analyze 3D FE model. Four different lesion configurations representative of the various types observed clinically for teeth were studied. A static point load of 500N was applied to the buccal and lingual cusp (Load A and B). The principal stresses in lesion apex, and vertical sectioned margin of cervical wall were analyzed. The results were as follows 1. The patterns of stress distribution were similar but the magnitude was different in four types of lesion 2. The peak stress was observed at mesial corner and also stresses concentrated at lesion apex. 3. The compressive stress under load A and the tensile stress under load B were dominant stress. 4. Under the load, lesion can be increased and harmful to tooth structure unless restored.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.96-112
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• 2002

In the present study, we have investigated the effects of centrally administered ginsenoside Rc or Rgl on the modulation of NMDA receptor and $GABA_A$ receptor binding in rat brain. The NMDA receptor binding was analyzed by quantitative autoradiography using $[^3H]MK-801$ binding, and $GABA_A$ receptor bindings were analyzed by using $[^3H]muscimol\;and\;[^3H]flunitrazepam$ in rat brain slices. Rats were infused with ginsenoside Rc or Rg1 ($10\;{\mu}g/10{\mu}l/hr$, i.c.v.) for 7 days, through pre-implanted cannula by osmotic minipumps (Alzet, model 2ML), The levels of $[^3H]MK-801$ binding were highly decreased in part of cortex and cingulated by ginsenoside Rc and Rgl. The levels of $[^3H]muscimol$ binding were strongly elevated in almost all regions of frontal cortex by the treatment of ginseoside Rc but decreased by ginsenoside Rg 1. However, the $[^3H]flunitrazepam$ binding was not modulated by ginsenoside Rc or ginsenoside Rgl infusion. These results suggest that prolonged infusion of ginsenoside could differentially modulate $[^3H]MK-801\;and\;[^3H]muscimol$ binding in a region-specific manner. Also, we investigated the influence of centrally administered ginsenoside on the regulation of mRNA levels of the family of NMDA receptor subtypes (NR1, NR2A, NR2B, NR2C) by in situ hybridization histochemistry in the rat brain. The level of NR1 mRNA is significantly increased in temporal cortex, caudate putamen, hippocampus, and granule layer of cerebellum in Rgl-infused rats as compared to control group. The level of NR2A mRNA is elevated in the frontal cortex. In contrast, it was decreased in CAI area of hippocampus in Rgl-infused rats. However, there was no significant change of NR1 and NR2A mRNA levels in Rc-infused rats. The level of NR2B mRNA is elevated in cortex, caudate putamen, and thalamus in both Rc- and Rg-infused rats. In contrast, NR2B level is decreased in CA3 in Rgl-infused rats. The level of NR2C mRNA is increased in the granule layer of cerebellum in only Rg1 but not Rc infused rats. These results show that structure difference of ginsenoside may diversely affect the modulation of expression of NMDA receptor subunit mRNA after infusion into cerebroventricle in rats.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.343-352
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• 2008

Frankincense, the gum resin derived from Boswellia species, is complex mixtures composed of about $5{\sim}9%$ highly aromatic essential oil, $65{\sim}85%$ alcohol-soluble resins, and the remaining water-soluble gums. The anti-inflammatory properties of frankincense, alcohole-soluble resins, are well-recognized, but the question of whether aromatic essential oil also plays a role in the allergic asthma remains unanswered. This study was performed to evaluate anti-inflammatory effects of Boswellia sacra essential oil (BSEO) on ovalbumin (OVA)-induced asthma mouse model. BALB/c mice after intraperitoneal OVA sensitization were challenged with intratracheal OVA. One experimental group was inhaled with 0.3% BSEO for the later 8 weeks. BALB/c mice were sensitized and challenged with OVA and developed airway eosinophilia, mucus hypersecretion, and airway hyperresponsiveness. In contrast, the BSEO treated mice had reduced a number of eosinophils among BALF cells, goblet cell hyperplasia, and airway hyperresponsiveness. Cytokine analysis of BALF revealed that BSEO caused an increase in Th1 cytokine (interferon-$\gamma$ (IFN-$\gamma$)) and a decrease in Th2 cytokines (interleukin-4 (IL-4), IL-5 and IL-13) levels. In addition, the OVA-specific serum IgE and eotaxin levels were also reduced. In mice inhaled BSEO, $CD4^+$, $CD3^+/CCR3^+$, and $B220^+/CD23^+$ mediastinal lymph nodes cells were also decreased. These results suggest that inhaled BSEO as a immunomodulator in Th1/Th2 mediated asthma may have therapeutic potential for the treatment in allergic airway inflammation by a simple, cost-effective way.