• Korean Journal of Remote Sensing
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• v.36 no.2_2
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• pp.351-363
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• 2020

It is well known that alluvial sediment located in coastal region has been easily affected by geohazard like ground subsidence, marine or meteorological disasters which threaten invaluable lives and properties. The subsidence is a sinking of the ground due to underground material movement that mostly related to soil compaction by water extraction. Thus, continuous monitoring is essential to protect possible damage from the ground subsidence in the coastal region. Radar interferometric application has been widely used to estimate surface displacement from phase information of synthetic aperture radar (SAR). Thanks to advanced SAR technique like the Small BAseline Subset (SBAS), a time-series of surface displacement could be successfully calculated with a large amount of SAR observations (>20). Because the ALOS-2 PALSAR-2 L-band observations maintain higher coherence compared with other shorter wavelength like X- or C-band, it has been regarded as one of the best resources for Earth science. However, the number of ALOS-2 PALSAR-2 observations might be not enough for the SBAS application due to its global monitoring observation scenario. Unfortunately, the number of the ALOS-2 PALSAR-2 Stripmap images in area of our interest, Busan which located in the Southeastern Korea, is only 11 which is insufficient to apply the SBAS time-series analysis. Although it is common that the radar interferometry utilizes multiple SAR images collected from same acquisition mode, it has been reported that the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application could be possible under specific acquisition mode. In case that we can apply the Stripmap-ScanSAR interferometry with the other 18 ScanSAR observations over Busan, an enhanced time-series surface displacement with better temporal resolution could be estimated. In this study, we evaluated feasibility of the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometric application using Gamma software considering differences of chirp bandwidth and pulse repetition frequency (PRF) between two acquisition modes. In addition, we analyzed the interferograms with respect to spectral shift of radar carrier frequency and common band filtering. Even though it shows similar level of coherence regardless of spectral shift in the radar carrier frequency, we found periodic spectral noises in azimuth direction and significant degradation of coherence in azimuth direction after common band filtering. Therefore, the characteristics of spectral bandwidth in the range and azimuth direction should be considered cautiously for the ALOS-2 PALSAR-2 Stripmap-ScanSAR interferometry.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.6 s.312
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• pp.65-84
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• 2006

In this paper, we present an improved image formation model and propose a color image enhancement based on the model. In the presented image formation model, an input image is represented as a product of global illumination, local illumination, and reflectance. In the proposed color image enhancement, an input RGB color image is converted into an HSV color image. Under the assumption of white-light illumination, the H and S component images are remained as they are and the V component image only is enhanced based on the image formation model. The global illumination is estimated by applying a linear LPF with wide support region to the input V component image and the local illumination by applying a JND (just noticeable difference)-based nonlinear LPF with narrow support region to the processed image, where the estimated global illumination is eliminated from the input V component image. The reflectance is estimated by dividing the input V component image by the estimated global and local illuminations. After performing the gamma correction on the three estimated components, the output V component image is obtained from their product. Histogram modeling is next executed such that the final output V component image is obtained. Finally an output RGB color image is obtained from the H and S component images of the input color image and the final output V component image. Experimental results for the test image DB built with color images downloaded from NASA homepage and MPEG-7 CCD color images show that the proposed method gives output color images of very well-increased global and local contrast without halo effect and color shift.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.3
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• pp.221-231
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• 1997

This paper presents an analysis of a hybrid direct-sequence/slow frequency hopped code division multiple access(DS/SFH-CDMA) system employing noncoherent M-ary frequency shift keying(MFSK) modulation in a multiple m-distribution fading environment. Multipath interfer- ence(MPI) and multiuser interference(MUI) is taken into accout and the spectral efficiency is calculated for uncoded as well as simple channel coding systems. The predetection multipath CCI canceller in conjunction with convolution coding is employed for improving the bit error rate(BER) performance. The BER of noncoherent hybrid system is obtained using a Gaussian interference approximation. From the results, we know that the error performance more deteriorates as the depth of fading becomes deeper. The DS part of the modulation combats the multipath interference, whereas the FH part is a predetection against large multiuser interference. It is shown that, for the con- sidered types of a channel coding, the use of a predetection coding is still essential for obtained a satisfactory bit error performance. The results show that the capacity of the DS/SFG-CDMA MFSK communication system increases in proportion to the length of PN code sequence in the presence of AWGN and MUI. In m-distribution fading environment the capacity increases in proportion to the fading index. The capacity is increased and error performance is improved when the CCI Canceller and Convolution code technique are adopted, respectively. From the results, it is known that the error performance of $4\times10^{-2}$ by adopting Canceller technique. Also convolutional coding technique is the improvement of error performance attains about $10^{-5}$ in code rate 1/2.

• KSBB Journal
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• v.11 no.4
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• pp.411-419
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• 1996

In this research, an extractive production system for alkaloids, where production and some degree of separation occur simultaneously, was developed in a way that the fast removal of alkaloid produced from the suspension cultures was done by capturing alkaloid with cyclodextrins. The alkaloid production was substantially enhanced up to 40 fold when the solid cultures of E. califonica cells treated with ${\beta}$-cyclodextrin compared to the control. The enhancement of alkaloid production was also observed in the suspension cultures. Interestingly, the production pattern seemed to change when the cultures were treated with ${\beta}$-cyclodextrin so that the major part of the alkaloids in the treated cultures was present in the medium, while the non-treated cultures produced the alkaloids intracellularly. ${\beta}$-cyclodextrin was the most effective one in terms of the alkaloid production among the cyclodextrilns(${\alpha}$-cylodextrin, ${\beta}$-cyclodextrin and ${\gamma}$-cyclodextrin) tested in the suspension cultures. ${\beta}$-cyclodextrin showed no adverse effect on the cell growth. The most effective concentration of ${\beta}$-cyclodextrin was observed around 1.5% (w/v) in the suspension cultures. The formation of the inclusion complex of the alkaloids with ${\beta}$-cyclodextrin in the suspension cultures was confirmed by detecting the shift of UV absorbance from 274 nm to 282 nm with a UV spectrophotometer.

• Journal of the Korean Society of Radiology
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• v.11 no.3
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• pp.123-129
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• 2017

Compton suppression apparatus using the Compton scattering response, by inhibiting part of the spectrum Compton continuum Compton continuum in the area of the peak analysis of the gamma rays that enables a clearer device. In order to find out the geometry structure of high-purity germanium detector(HPGe) -NaI(TI) and to optimize the effect of movement, Monte Carlo simulation was used to grasp the behavioral characteristics of Compton suppression and compare several layout structures. And applied to the cylinder beaker used for the environmental measurement by using the efficiency according to the distance. For the low-energy source such as 81 keV, the Compton continuum is scarcely developed and the suppression effect is also insignificant because the scattering cross-section of the Compton effect is relatively low. In the spectrum for the remaining energy, it can be seen that the Compton continuum part is suppressed in a certain energy range. Compton suppression effect was not significantly different from positional shift. average reduction factor(ARF) value was about 1.08 for 81 keV and about 1.23 for 1332.4keV energy at the highest value. It can be seen that suppression over the Compton continuum region of the energy spectrum is a more appropriate arrangement. Therefore, it can be applied to various environmental sample measurement through optimized structure.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.508-514
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• 2013

2Department of Marine Molecular Biotechnology, College of Life Science, Gangneung-Wonju National University Recently, we reported that diarylheptanoid hirsutenone (HST) effectively inactivated T lymphocytes. However, it has not been evaluated whether HST is involved in calcineurin or calmodulin inactivation. In the present study, cells were treated with T-cell inhibitors with or without HST. Our results revealed that HST successfully inhibited expression of T-helper type I (Th1) and Th2 cytokines. Co-treatment with HST and nuclear factor-activated T cell (NFAT) activation inhibitor III (INCA-6) showed a more sensitive effect than that with other inhibitors, suggesting that HST contributes to inhibition of dephosphorylation of NFAT in the cytosol. HST up-regulated cell cycle arrest genes and inhibited the growth of Staphylococcus aureus. These effects were confirmed in an NFAT electrophoretic-mobility shift assay via successful inhibition of NFAT translocation and in the histological recovery in a 2,4-dinitrochloro benzene-induced in vivo model. Taken together, HST was shown to effectively inhibit T-cell activation via inhibition of cytosolic NFAT dephosphorylation, similar to INCA-6.

• Journal of Acupuncture Research
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• v.21 no.6
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• pp.19-36
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• 2004

Objective : The purpose of this study was to investigate the effect of Bee Venom and Melittin Solution on the lipopolysaccharide(LPS) and sodium nitroprusside(SNP)-induced expression of prostaglandin $E_2(PGE_2)$, cyclooxygenase-2(COX-2), nuclear factor kappa B($NF-{\kappa}B$) and nuclear factor kappa B($NF-{\kappa}B$) dependent luciferase activity in RAW 264.7 cells, a murine macrophage cell line. Methods : The expression of PGE2 was determined by determination of $PEG_2$, COX-2 was by western blotting with corresponding antibodies, $NF-{\kappa}B$ was by gel mobility shift assay method and $NF-{\kappa}B$ dependent luciferase activity was investigated by luciferase assay in RAW 264.7 cells. Results : 1. LPS and SNP-induced expression of $PEG_2$ was significant after 24hour. 2. The 0.5, 1 and $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly LPS-induced expression of $PEG_2$ and, the $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly SNP-induced expression of $PEG_2$ compared with control, respectively. The 0.5 and $1{\mu}g/mL$ of bee venom could not significantly inhibit SNP-induced expression of $PEG_2$ compared with control. 3. The $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly LPS and SNP-induced expression of COX-2 compared with control, respectively. The 0.5 and $1{\mu}g/mL$ of bee venom inclined to decrease LPS and SNP-induced expression of COX-2 compared with control. 4. The 0.5, 1 and $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly LPS and SNP-induced expression of $NF-{\kappa}B$ compared with control, respectively. 5. The 0.5, 1 and $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly LPS-induced expression of $NF-{\kappa}B$ dependent luciferase activity and the 1 and $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly SNP-induced expression of $NF-{\kappa}B$ dependent luciferase activity compared with control, respectively. The $NF-{\kappa}B$ inhibitor also inhibited significantly LPS and SNP-induced expression of $NF-{\kappa}B$ dependent luciferase activity compared with control. 6. The 0.5, 1 and $5{\mu}g/mL$ of bee venom and the 5 and $10{\mu}g/mL$ of melittin solution inhibited significantly LPS + IFN-${\gamma}$, TNF-${\alpha}$ and LPS + TNF-${\alpha}$-induced expression of $NF-{\kappa}B$ dependent luciferase activity compared with control, respectively. The $NF-{\kappa}B$ inhibitor also inhibited significantly LPS and SNP-induced expression of $NF-{\kappa}B$ dependent luciferase activity compared with control. Conclusions : These results suggest the inhibitory action of bee venom and melittin solution on the inflammatory mediators such as $PEG_2$, COX-2 and $NF-{\kappa}B$.

• Food Science and Preservation
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• v.18 no.3
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• pp.294-301
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• 2011

The aim of this study was to investigate the changes in identification markers of irradiated foods after treatment of the full-overlapped gravitational field energy (FGFE). Wheat and soybean samples were irradiated at 0-5 kGy of Co-60 gamma energy, and analyzed for photostimulated and thermo luminescence characteristics (PSL and TL) and sprouting rate at 0 and 6th month after FGFE treatment. As a screening method for irradiated samples, PSL photon counts (PCs) for the non-irradiated samples appeared negative (<700 PCs), while irradiated samples gave positive (>5,000 PCs). But FGFE-treated irradiated samples appeared intermediate (700-5,000 PCs), showing decreased PCs during storage. The TL analysis on irradiated samples exhibited glow curve peaks in range of $150-200^{\circ}C$ and TL ratio ($TL_1/TL_2$) was also >0.1. Therefore, identification of irradiated samples was possible using thermoluminescence. But the glow curve range of FGFE-treated irradiated samples shifted from $150-200^{\circ}C$ to $180-230^{\circ}C$ and TL intensity was decreased 37-60% resulting from FGFE treatment. After 6 months of storage, all the samples showed a decrease in TL intensity, but identification was still possible. The sprouting rate of irradiated samples decreased by about 72%, whereas that of FGFE-treated irradiated samples showed by about 85%, as compared to non-irradiated samples. More detailed study is required to investigate sprouting phenomena for FGFE-treated samples.