• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.443-446
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• 1991

In the conventional current control methods for the current-type reactive power compensators, it is usual to compare the reactive reference current signal with the triangular wave and hence to generate the ON-OFF signals for the semiconductor reactive power compensator. To improve the response as well as the control capability, the delta modulated current control technique is proposed in this paper and studied theoretically.

• Bulletin of the Korean Mathematical Society
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• v.49 no.6
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• pp.1199-1211
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• 2012

In this paper we give an introduction to the theory of universal central extensions of perfect Lie algebras. In particular, we will provide a model for the universal coverings of Lie tori and we show that automorphisms and derivations lift to the universal coverings. We also prove that the universal covering of a Lie ${\Lambda}$-torus of type ${\Delta}$ is again a Lie ${\Lambda}$-torus of type ${\Delta}$.

• Journal of Life Science
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• v.27 no.11
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• pp.1369-1375
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• 2017

The purpose of this study was to investigate the cellular characterization of phospholipase C-${\delta}1$ in olive flounders (Paralichthys olivaceus). In general, phospholipase C signaling pathways are distributed in nuclei at plasma membranes and in cytoplasms, although the pathways' nuclear localization mechanisms are unclear. P. olivaceus duplicates type-A PoPLC-${\delta}1$ (PoPLC-${\delta}1A$), which has a high similarity to the human isoform PLC-${\delta}$; type-B PoPLC-${\delta}1$ (PoPLC-${\delta}1B$ [Sf]), which has a low similarity to the human isoform PLC-${\delta}$ and the alternative splice variant PoPLC-${\delta}1B$ (Lf), which has a nuclear localization signal (NLS) and a nuclear export signal (NES) for nuclear imports and exports, respectively. This study confirmed the effects of the cellular localization and translocation of GFP-tagged PoPLC-${\delta}1A$, PoPLC-${\delta}1B$ (Sf) and PoPLC-${\delta}1B$ (Lf). It administered treatments of $Ca^{2+}$ ionophore ionomycin and endoplasmic reticulum (ER)-$Ca^{2+}$ pump inhibitor thapsigargin to hirame natural-embryo (HINAE) cells. A laser-scanning confocal microscope was used. GFP-tagged PoPLC-${\delta}1A$ was distributed to the cellular organelles, rather than to the cytoplasms and cytomembranes, when PoPLC-${\delta}1B$ (Lf) and PoPLC-${\delta}1B$ (Sf) were localized at the plasma membranes. The treatments of ionomycin and thapsigargin showed the accumulation of PoPLC-${\delta}1A$ in the nuclei when PoPLC-${\delta}1B$ (Lf) nucleocytoplasmic shuttling and PoPLC-${\delta}1B$ (Sf) nucleocytoplasmic shuttling were not observed. The results were the first evidence that PoPLC-${\delta}1A$, which contains functional, intact NES sequences, has a main role in nucleocytoplasmic shuttling and translocation in fish.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.358-374
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• 1999

This study measured the relative displacements of the five-unit fixed partial dentures as cast with the same fixed partial dentures sectioned and assembled by investment-soldering, solder-ing stand-soldering, and cast-joining techniques A total of fifteen specimens using a type IV gold alloy were one-piece cast as control and then sectioned and assembled five test specimens for each method were prepared. A computerized three dimensional coordinate measuring machine and specially designed cylinder for this study were used. Displacement was defined by six displacement variables for the each of cylinders incorporated in each casting: three component displacements(${\Delta}Lx,\;{\Delta}Ly,\;and\;{\Delta}Lz$) and rotational displacements(${\Delta}{\theta}x,\;{\Delta}{\theta}y,\;{\Delta}{\theta}z$). The global displacement was computed using the mathematical formula ${\Delta}R$ = Global displacement =$\sqrt{{(x'-x)}^2+{(y'-y)}^2+{(z'-z)}^2}$ Under the conditions of this study, the following conclusions were drawn: 1. The investment-soldering group showed the largest mean value of final global displacements, followed by stand-soldering group, cast-joining group and one-piece cast group. However, between the mean values of final global displacement for the cast-joining group and one-piece cast group, there was no significant difference. 2. For investment-soldering and stand-soldering groups, the greater global displacements were recorded in soldering phase than in indexing or investing phase. 3. For one-piece cast group, the displacements occured mostly in the casting phase. And for cast-joining group, there was no significant difference in global displacements among the fabricating procedures. 4. Intercentroidal distance decreased in framework-patterning, solder-indexing, solder-standing, and soldering phases, but increased in investment block-investing and casting phases. 5 Specially designed cylinder for touch-trigger type coordinate measuring machine was validated.

• Current Optics and Photonics
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• v.1 no.3
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• pp.175-185
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• 2017

The aerosol optical properties such as depolarization ratio (${\delta}$) and aerosol extinction-to-backscatter ratios (S, LIDAR ratio) and ${\AA}ngstr{\ddot{o}m$ exponent (${\AA}$) derived from measurement with AERONET sun/sky radiometer at Gangneung-Wonju National University (GWNU), Gangneung, Korea ($37.77^{\circ}N$, $128.87^{\circ}E$) during a winter season (December 2014 - February 2015) are presented. The PM concentration measurements are conducted simultaneously and used to identify the high-PM events. The observation period was divided into three cases according to the PM concentrations. We analysed the ${\delta}$, S, and ${\AA}$ during these high PM-events. These aerosol optical properties are calculated by the sun/sky radiometer data and used to classify a type of aerosols (e.g., dust, anthropogenic pollution). The higher values of ${\delta}$ with lower values of S and ${\AA}$ were measured for the dust particles. The mean values of ${\delta}$, S, and ${\AA}$ at 440-870 nm wavelength pair (${\AA}_{440-870}$) for the Asia dust were 0.19-0.24, 36-56 sr, and 0.48, respectively. The anthropogenic aerosol plumes are distinguished with the lower values of ${\delta}$ and higher values of ${\AA}$. The mean values of spectral ${\delta}$ and ${\AA}_{440-870}$ for this case varied 0.06-0.16 and 1.33-1.39, respectively. We found that aerosol columnar optical properties obtained from the sun/sky radiometer measurement are useful to identify the aerosol type. Moreover, the columnar aerosol optical properties calculated based on sun/sky radiometer measurements such as ${\delta}$, S, and ${\AA}$ will be further used for the validation of aerosol parameters obtained from LIDAR observation as well as for quantification of the air quality.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.526-530
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• 2010

Isopentenyl diphosphate(IPP) isomerization to dimethylallyl diphosphate(DMAPP) is an important step for the efficient production of isoprenoids such as lycopene, ${\beta}$-carotene, astaxanthin, etc. The type II isopentenyl diphosphate isomerase gene from Synechocystis sp. PCC6803(sll1556, Syidi2) was cloned and expressed in Escherichia coli $DH5{\alpha}$. When E. coli $DH5{\alpha}$ harboring lycopene synthesis genes, crtE, crtB, and crtI and mevalonate pathway genes, MvK1, MvK2, and Mvd, was cultured on LB medium containing mevalonate, the strain grew very slowly be due to the toxicity of isopentenyl diphosphate derived from mevalonate. When Syidi2 was introduced to E. coli $DH5{\alpha}$ harboring the lycopene synthesis genes and mevalonate pathway genes, growth on mevalonate medium was fully restored and the colony showed red color indicating lycopene formation. The growth rate of the mutant strain, E. coli $DH5{\alpha}$(idi::${\Delta}km$), was very slow because of IPP accumulation and DMAPP deprivation. Ultimately the idi mutant was complemented by introducing the Syidi2 gene.

• Transactions on Electrical and Electronic Materials
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• v.7 no.3
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• pp.149-153
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• 2006

An attempting to produce a p-type diluted magnetic semiconductor (DMS) using $Ti_{1-x}Co_xO_{2-\delta}-based$ thin films was made by suitable control of the deposition parameters including deposition temperature, deposition pressure, and doping level using a pulsed laser deposition method. T$Ti_{0.97}Co_{0.03}O_{2-\delta}-based$ (TCO) films deposited at $500^{\circ}C$ at a pressure of $5\times10^{-6}$ Torr showed an anomalous Hall effect with p-type characteristics. On the other hand, films deposited at $700^{\circ}C$ at $5\times10^{-6}$ Torr showed n-type behaviors by a decreased solubility of cobalt. The charge carrier concentration in the p-type TCO films was approximately $7.9\times10^{22}/cm^3$ at 300 K and the anomalous Hall effect in the p-type TCO films was controlled by a side-jump scattering mechanism. The magnetoresistance (MR), measured at 5 K in p-type TCO films showed a positive behavior in an applied magnetic field and the MR ratio was approximately 3.5 %. The successful preparation of p-type DMS using the TCO films has the potential for use in magnetic tunneling junction devices.

• Progress in Medical Physics
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• v.8 no.1
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• pp.3-15
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• 1997

Adrenal chromaffin cells secrete catecholamine in response to acetylcholine. The secretory response has absolute requirement for extracellular calcium, indication that $Ca^{2+}$ influx through voltage dependent $Ca^{2+}$ channel (VDCC) is the primary trigger of the secretion cascade. Although the existence of various types of $Ca^{2+}$ channels has been explored using patch clamp technique in adrenal chromaffin cells, the contribution of different types of $Ca^{2+}$ channels to catecholamine secretion remains to be established. To investigate the quantative contribution of different types of $Ca^{2+}$ channels to cate-cholamine secretion, $Ca^{2+}$ current($I_{Ca}$) and the resultant membrane capacitance increment($\Delta{C}_{m}$) were simultaneoulsy measured. Software based phasor detector technique was used to monitor $\Delta{C}_{m}$. After blockade of L type VDCC with nicardipine (1$\mu$M), $I_{ca}$ was blocked to 43.85$\pm$6.72%(mean$\pm$SEM) of control and the resultant ㅿC$_{m}$ was reduced ot 30.10$\pm$16.44% of control. In the presence of nicardipine and $\omega$-conotoxin in GVIA(l$\mu$M), an N type VDCC antagonist, $I_{ca}$ was blocked to 11.62$\pm$2.96% of control and the resultant $\Delta{C}_{m}$ was reduced to 26.13$\pm$8.25% of control. Finally, in the presence of L, N, and P type $Ca^{2\pm}$ channel antagonists(nicardipine, $\omega$-Conotoxin GVIA, and $\omega$-agatoxin IVA, respectively), $I_{ca}$ and resultant $\Delta{C}_{m}$ were almost completely blocked. From the observation of parallel effects of $Ca^{2+}$ channel antagonists on $I_{ca}$ and $\Delta{C}_{m}$, it was concluded that L, N, and also P type $Ca^{2+}$ channels served and $Ca^{2+}$ source for exocytosis and no difference was observed in their efficiency to evoke exocytosis amost L, N, and P type $Ca^{2+}$ channels.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.67-74
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• 2018

Thermoelectric thin film modules were fabricated by electroplating p-type $Sb_2Te_3$and n-type $Bi_2Te_3$ thin film legs with the same thickness of $20{\mu}m$ and different diameters of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$, respectively. The output voltage and output power of thin film modules were measured and compared as a function of the leg diameter. The modules processed with thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter exhibited open circuit voltages of 365 mV at ${\Delta}T=36.7K$, 142 mV at ${\Delta}T=37.5K$, and 53 mV at ${\Delta}T=36.1K$, respectively. Maximum output powers of $845{\mu}W$ at ${\Delta}T=36.7K$, $631{\mu}W$ at ${\Delta}T=37.5K$, and $276{\mu}W$ at ${\Delta}T=36.1K$ were obtained for the modules fabricated with the thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.991-994
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• 2009

This paper reports of camera detection of Mura. The type, location, size, orientation and amplitude are found. As the luminance variation in Mura is down to less than app. 0.3 %, measurement apparatus, techniques and algorithms are developed to measure low noise data and to extract the Mura from data with the residual noise in the same magnitude as the Mura.