• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.6
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• pp.761-768
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• 1999

This paper is studied to find the optimum condition of double-inlet Sirocco fan installed in an indoor PAC for low noise operation by the Taguchi method. The goal of this study is to obtain the best combination of each control factor which results in a desired flowrate of Sirocco fan with minimum variability. In this study, the parameter design of the Taguchi method is adopted for robust design by the dynamic characteristic analysis using orthogonal arrays and S/N ratios. The flowrate measurements are conducted by using a multiple-nozzle-type fan tester according to the orthogonal array L9($3^4$). The results of this study can be summarized as follows ; (i) The optimum condition of control factor is a set of where A is an inner to outer diameter ratio($D_1/D_2$), B is a width to outer diameter ratio($L/D_2$), C is a blade attachment angle(${\theta}$) and D is a number of blade(Z), (ii) The flowrate under the optimum condition satisfies the equation $y=0.0384{\cdot}M$ where M is a signal factor, namely number of revolution. The flowrate performance improves about 7.3% more largely as compared with the current condition, which results in about 35RPM reduction of number of revolution for the target flowrate $18.5m^3/min$, and (iii) The sensitivity analysis shows that the major factors in contribution to flowrate performance are A, B, and D ; the percentage contributions of each control factor are 44.01%(Z), 26.77%($D_1/D_2$) and 20.42%($L/D_2$).

• The Korean Journal of Pain
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• v.34 no.1
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• pp.19-26
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• 2021

Background: Prolotherapy is a proliferation therapy as an alternative medicine. A combination of dextrose solution and lidocaine is usually used in prolotherapy. The concentrations of dextrose and lidocaine used in the clinical field are very high (dextrose 10%-25%, lidocaine 0.075%-1%). Several studies show about 1% dextrose and more than 0.2% lidocaine induced cell death in various cell types. We investigated the effects of low concentrations of dextrose and lidocaine in fibroblasts and suggest the optimal range of concentrations of dextrose and lidocaine in prolotherapy. Methods: Various concentrations of dextrose and lidocaine were treated in NIH-3T3. Viability was examined with trypan blue exclusion assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Migration assay was performed for measuring the motile activity. Extracellular signal-regulated kinase (Erk) activation and protein expression of collagen I and α-smooth muscle actin (α-SMA) were determined with western blot analysis. Results: The cell viability was decreased in concentrations of more than 5% dextrose and 0.1% lidocaine. However, in the concentrations 1% dextrose (D1) and 0.01% lidocaine (L0.01), fibroblasts proliferated mildly. The ability of migration in fibroblast was increased in the D1, L0.01, and D1 + L0.01 groups sequentially. D1 and L0.01 increased Erk activation and the expression of collagen I and α-SMA and D1 + L0.01 further increased. The inhibition of Erk activation suppressed fibroblast proliferation and the synthesis of collagen I. Conclusions: D1, L0.01, and the combination of D1 and L0.01 induced fibroblast proliferation and increased collagen I synthesis via Erk activation.

• Microbiology and Biotechnology Letters
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• v.24 no.5
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• pp.553-559
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• 1996

We have designed nucleotide sequences of hEGF structural gene to eliminate the N-terminal methionine residue incorporated during the translation initiation step, and constructed recombinant human epidermal growth factor (rhEGF) secretion plasmids pYHB101, and pYHB2 in which pelB signal sequence-hEGF gene was expressed under the control of the T7, and tac promoter, respectively. We also constructed pYHB1 vector which contains rhEGF gene controlled by T7 promoter. The transformant with pYHB101 showed relatively slow growth pattern compared to the transformant with pYHB1. However, we observed that the transformant with pYHB101 secreted rhEGF of 13 mg/l significantly after 5 hr induction with 1 mM IPTG and that the T7 promoter was more effective than tac promoter when connected to pelB signal sequence. The amount of rhEGF was 14 mg/l under the sub-optimized condition.

• Journal of Sensor Science and Technology
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• v.8 no.2
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• pp.148-153
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• 1999

In this paper, we developed and implemented the geological magnetic filter for the improvements of the signal to noise ratio of the magnetic detection system. Using the geological magnetic filter, we can remove the coherent noises in the time domain and improve the signal to noise ratio of the magnetic detection system. Numerical simulation results show that geological magnetic filter can excellently remove the sensor misalignment effects and the regular short range local noise as well as it delete the coherent noises. We confirmed that the geological magnetic filter improved the signal to noise ratio about 19dB and deleted the coherent noises with restoring the source magnetic signal through experiments by implemented system.

• Development and Reproduction
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• v.19 no.2
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• pp.61-67
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• 2015

The immediate early gene c-fos has long been known as a molecular marker of neural activity. The neuron's activity is transformed into intracellular calcium influx through NMDA receptors and L-type voltage sensitive calcium channels. For the transcription of c-fos, neural activity should be strong enough to activate mitogen-activated protein kinase (MAPK) signaling pathway which shows low calcium sensitivity. Upon translation, the auto-inhibition by Fos protein regulates basal Fos expression. The pattern of external stimuli and the valence of the stimulus to the animal change Fos signal, thus the signal reflects learning and memory aspects. Understanding the features of multiple components regulating Fos signaling is necessary for the optimal generation and interpretation of Fos signal.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.213-223
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• 2009

Lipid transfer proteins (LTPs) are widely distributed in the plant kingdom, but their functions remain elusive. The proteins AlLTP2-4 were isolated from three related Allium plants: garlic (A. sativum L.), Welsh onion (A. fistulosum L.), and Nanking shallot (A. ascalonicum L.). These novel proteins comprise a new class of LTPs associated with the Ace-AMP1 from onion (A. cepa L.). The AlLTP genes encode proteins harboring 132 common amino acids and also share a high level of sequence identity. Protein characteristics and phylogenetic analysis suggest that LTPs could be classified into five distinct groups. The AlLTPs were clustered into the most distantly related plant LTP subfamily and appeared to be restricted to the Allium species. In particular, the number of amino acids existing between the fourth and fifth Cys residue was suggested as a conserved motif facilitating the categorization of all the LTP-related proteins in the family. Unlike other LTPs, AlLTPs harboring both the putative C-terminal propeptide and N-terminal signal peptide were predicted to be localized to cytoplasmic vacuoles. When a chimeric GFP protein fused with both N-terminal and C-terminal AlLTP2 signal peptides was expressed in rice cells, the fluorescence signal was detected in the endomembrane compartments, thereby confirming that AlLTPs are an unprecedented intracellular type of LTP. Collectively, our present data demonstrate that AlLTPs are a novel type of LTP associated with the Allium species.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.317-325
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• 2015

Peach (Prunus persica L.) is a model species for stone fruit studies within the Rosaceae family. Auxin plays an important role in the development of peach fruit. To reveal the distribution of auxin in the tissues of peach fruit, immunohistochemical localization of IAA was carried out in the seed, mesocarp, and endocarp in developing peach fruit using an anti-indole-3-acetic acid (anti-IAA) monoclonal antibody. A strong IAA signal was observed throughout the outer and inner integument during peach fruit development, and the distribution was zonal. The IAA signal was mainly focused in mucilage layers in the outer integument. The outer integument may function to produce or store IAA in the seed; a strong IAA signal was detected in the cells around the vascular tissue, whereas a weak IAA signal was located in the vascular tissues. In the mesocarp, the cells around the vascular bundle tissue gave rise to an IAA signal that increased in the late phase of fruit growth, which coincided with a significant increase in fruit growth. The distribution of IAA, however, was changed when fruit was treated with auxin transport inhibitors NPA (1-N-naphthylphthalamic acid) or TIBA (2, 3, 5-triiodobenzoic acid); in mesocarp tissues, an IAA signal was detected mainly in vessels of the treated fruit. During the critical period of endocarp lignification, the vessel lignification process was negatively correlated with IAA signal. The present results confirmed that the distribution of IAA was different in various tissues of peach fruit according to the developmental stage. This research provides cytological data for further study of the regulatory mechanism of auxin in peach fruit.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9C
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• pp.914-920
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• 2006

In this paper, we introduce a new partial transmit sequence (PTS) orthogonal frequency division multiplexing (OFDM) scheme with low computational complexity. In the proposed scheme, $2^n$-point inverse fast Fourier transform (IFFT) is divided into two parts. An input symbol sequence is partially transformed using the first l stages of IFFT into an intermediate signal sequence and the intermediate signal sequence is partitioned into a number of intermediate signal subsequences. Then, the remaining n - l stages of IFFT are applied to each of the intermediate signal subsequences and the resulting signal subsequences are summed after being multiplied by each member of a set of W rotating vectors to yield W distinct OFDM signal sequences. The one with the lowest peak to average power ratio (PAPR) among these OFDM signal sequences is selected for transmission. The new PTS OFDM scheme reduces the computational complexity while it shows almost the same performance of PAPR reduction as that of the conventional PTS OFDM scheme.

• Korean Journal of Optics and Photonics
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• v.7 no.3
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• pp.196-199
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• 1996

The amplitude LSF(Line spread function, $C_1e^{{o^2}{x^2}}$ or amplitude impulse) of the Gaussian apodized annular pupil is found to be same to that of the full aperture LSF($C_0e^{{o^2}{x^2}}$). $C_0$ and $C_1$ depending on $\sigma$, ${\omega}_0=\frac{2{\pi}}{\lambda}\;\frac{a_0}{l}$ and ${\omega}_0'=\frac{2{\pi}}{\lambda}\;\frac{a_0'}{l}$ which are the geometric parameter and pupil coordinates of the annular pupil. The important inequality relation among ${\omega}_0,\;{\omega}_0'$, a (fraction of diffraction amplitude) and $\sigma$ is obtained. It is $\frac{{\omega}_0}{\sqrt{2}}<{\sigma}{\le}(\frac{1-a}{2a})^{1/2}\;{\omega}_0$, and in the case of $a=e^{-1},\;a_0'{\le}0.34a_0$. The case of λ=0.013${\mu}{\textrm}{m}$, l=20 cm, $a_0=5cm$ and $a_0=0.34a_0=1.7cm$ give a Gaussian apodized superresolution ${\Delta}=\frac{\sqrt{log2}}{\sigma}=0.008{\mu}m$ annular pupil with the intensity signal equal to $e_{-2}$ times the signal obtainable by using the full aperture system(a=1)

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.40.1-40.1
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• 2021

Gwacheon National Science Museum(GNSM) has a 7.2m radio telescope, which is only one possessed by a science museum in Korea. In 2020, performance of the telescope had been improved in the way of a new antenna control system, receiver system, control and analysis software. New AC motors, limiters and encoders was installed and the new receive system can observe L-band(1.4GHz) and S-band(2.8GHz), L-band and Ka-band(33GHz) equipped previously. Using theses upgraded system we have developed educational programs, which are 'The Sun seen in radio' and 'The Universe seen in radio'. In the former, the sun is observed with several methods and show analysed data to participants. In the latter, various radio sources, the moon, supernova remnants and HI gas, and even signal from artificial satellites are observed. In addition, SETI demo data can be shown and demonstrates how to find artificial signal extraterrestrial intelligence could send.