• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1638-1643
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• 2018

Multi-layer ceramic capacitors as decoupling capacitor were fabricated by dielectric composition with a high dielectric constant. The fabricated decoupling capacitors were embedded in the PCB of the 10G RF transceiver module and evaluated for the characteristics of electrical noise by the level of AC input voltage. In order to further improve the electrical properties of the $BaTiO_3$ based composite, glass frit, MgO, $Y_2O_3$, $Mn_3O$, $V_2O_5$, $BaCO_3$, $SiO_2$, and $Al_2O_3$ were used as additives. The electrical properties of the composites were determined by various amounts of additives and optimum sintering temperature. As a result of the optimized composite, it was possible to obtain a density of $5.77g/cm^3$, a dielectric constant of 1994, and an insulation resistance of $2.91{\times}10^{12}{\Omega}$ at an additive content of 5wt% and a sintering temperature of $1250^{\circ}C$. After forming a $2.5{\mu}m$ green sheet using the doctor blade method, a total of 77 layers were laminated and sintered at $1180^{\circ}C$. A decoupling capacitor with a size of $0.6mm(W){\times}0.3mm(L){\times}0.3mm(T)$ (width, length and thickness, respectively) and a capacitance of 100 nF was embedded using a PCB process for the 10G RF Transceiver modules. In the range of AC input voltage 400mmV @ 500kHz to 2200mV @ 900kHz, the embedded 10G RF Transceiver modules evaluated that it has better electrical performance than the non-embedded modules.

• Journal of Navigation and Port Research
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• v.39 no.4
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• pp.353-360
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• 2015

The offshore oil production requires a huge amount of cost and time accompanied by multiple variables due to the peculiar nature of 'offshore'. And every process concerned is controlled by elaborate series of plans for reducing loss of lives, environment and property. This paper treats an optimization problem for offshore oil production and transportation. We present an offshore production and transportation network to define scope of the problem and construct a mixed integer linear programming model to tackle it. To demonstrate the validity of the optimization model presented, some computational experiments based on hypothetical offshore oil fields and demand markets are carried out by using MS Office Excel solver. The downstream of the offshore production and transportation network ends up with the maritime transportation problem distributing the crude oil produced from offshore fields to demand markets. We used MoDiSS(Model-based DSS in Ship Scheduling) which was built to resolve this maritime transportation problem. The paper concludes with the remark that the results of the study might be meaningfully applicable to the real world problems of offshore oil production and transportation.

• Applied Microscopy
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• v.39 no.3
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• pp.253-260
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• 2009

GM-CSF is a multipotent growth factor, which also plays an important role during the process of wound healing. rrhGM-CSF was specifically produced from rice cell culture in our laboratory (Hanson Biotech Co., Ltd, Daejeon). The rrhGMCSF contains more oligosaccharide side chains than any other types of GM-CSF. This work was taken to evaluate the influence on wound healing of rrhGM-CSF in male golden hamsters. Full thickness skin defects of 9 mm in diameter were made in the back of hamsters, and 100 ${\mu}L$ ointment containing rrhGM-CSF 50 ${\mu}g/mL$ was applied. Control groups were given ointment without rrhGM-CSF. The wound sizes were relatively reduced and skin was well regenerated in the experimental group compared with the control group. Structurally, reepithelialization and architecture of the skin following injury were well accomplished in the experimental group. And also, positive reaction of PCNA of the skin following injury was more prominent in rrhGM-CSF containing ointment treatment group. Since this type of GM-CSF has highly glycosylated side chains, the effectiveness might be retain longer and stable, regarding acceleration of wound healing in the animal model. The present study has important implications for further development of the therapeutic manipulation of wound healing using rrhGM-CSF.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.139-143
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• 2010

The relationship between ADP-glucose pyrophosphorylase (AGP) activity and the characteristics of related pod setting in developing seed of soybean cv. Pungsannamulkong, Iksannamulkong, Geumjeongkong #1 and Danpaheuk was studied. AGP activity during the accumulate of the majority of dry matter in all cultivars suggested that this enzyme might be associated with this process. At the Vn and R1 stages, AGP activity of full-grown leaves of Pungsannamulkong, Iksannamulkong, Geumjeongkong #1 was the highest and then decreased progressively. However AGP activity of Danpaheuk was the lowest and also had lower seed weight. So regulation of matter accumulation in developing soybean seeds may also depend on AGP activity. AGP capacities as expressed by AGP activity seem to have a good predicting value for the dry matter of leaf and seed at R1 to R5 stages in our series of R3 stage genotypes. Western blots probed with antibody specific to the subunit of potato AGP revealed a single 60KD immunoreactive band that changed in intensity during the growth cycle in association with changes in total AGP activity.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.176-183
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• 2012

Eukaryotic translation termination is governed by eRF1 and eRF3. eRF1 recognizes the stop codons and then hydrolyzes peptidyl-tRNA. eRF3, which facilitates the termination process, belongs to the GTPase superfamily. In this study, the effect of the MC domain of eRF1a (eRF1aMC) on the GTPase activity of eRF3 was analyzed using fluorescence spectra and high-performance liquid chromatography. The results indicated eRF1aMC promotes the GTPase activity of eRF3, which is similar to the role of eRF1a. Furthermore, the increased affinity of eRF3 for GTP induced by eRF1aMC was dependent on the concentration of $Mg^{2+}$. Changes in the secondary structure of eRF3C after binding GTP/GDP were detected by CD spectroscopy. The results revealed changes of conformation during formation of the eRF3C GTP complex that were detected in the presence of eRF1a or eRF1aMC. The conformations of the eRF3C eRF1a GTP and eRF3C eRF1aMC GTP complexes were further altered upon the addition of $Mg^{2+}$. By contrast, there was no change in the conformation of GTP bound to free eRF3C or the eRF3C eRF1aN complex. These results suggest that alterations in the conformation of GTP bound to eRF3 is dependent on eRF1a and $Mg^{2+}$, whereas the MC domain of eRF1a is responsible for the change in the conformation of GTP bound to eRF3 in Euplotes octocarinatus.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.3
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• pp.199-206
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• 2013

Electrowinning process in pyroprocessing recovers U (uranium) and TRU (Trans Uranium) elements simultaneously from spent fuels using a liquid cadmium cathode (LCC). When the solubility limit of U deposits over 2.35wt% in Cd, U dendrites were formed on the LCC surface during the electrodeposition at $500^{\circ}C$. Due to the high surface area of dendritic U, the deposits were not submerged into the liquid cadmium pool but grow out of the LCC crucible. Since the U dendrites act as a solid cathode, it prevents the co-deposition of U and TRUs. In this study, the electrodeposition of U onto a LCC was carried out at 440 and $500^{\circ}C$ to compare the morphology and component of U deposits. The U deposits at $440^{\circ}C$ have a specific shape and were stacked regularly at the center of the LCC pool, while the U dendrites (i.e., ${\alpha}$-phase) at $500^{\circ}C$ were grow out of the LCC crucible. Through the microscopic observation and XRD analysis, the electrodeposits at $440^{\circ}C$, which have a round shape, were identified as an intermetallic compound such as $UCd_{11}$. It can be concluded that the LCC electrowinning operation at $440^{\circ}C$ achieves the co-recovery of U and TRU without the formation of U dendrites.

• Resources Recycling
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• v.19 no.6
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• pp.43-50
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• 2010

The crisis of energy gives rise to the growing concerns over continuing uncertainty in the energy market. Under these circumstances, there are also increasing interests on coals. In particular, Low Rank Coal (LRC) is receiving gradual attentions from green industry. But due to is high moisture content range from 30 - 60%, drying process has to be preceded before being utilized as power plant. In this study drying kinetics of LRC is induced by using a fixed-bed reactor. The drying kinetics was evaluated in from of the particle size, the inlet gas temperature, the drying time, the gas velocity, and the LID ratio. The consideration of the reynold's number was taken for correction of gas velocity, particle size and LID was taken for correction of reactor diameter, packing height of coal. As being seen as characteristic of drying coal, it can be found that fixed-bed reactor can contributed to active drying of free water. In this sense, it could be considered that phase boundary reaction is appropriate mechanism.

• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.61-76
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• 2016

Purpose: In order to use a word as academic terminology, we must first take a look at the meaning of that word as it is commonly used and then consider whether or not the connotation of that word is suitable to be used as academic terminology. Presently, the word Pumjil(品質) is being used as academic terminology occupying an important position in the field of business administration in Korea and is usually translated into English as 'quality'. The same is true in Japan. However, as is the case with many Korean words, the meaning that the word implies has a tendency to change gradually over time. This tendency can account for the changes or additions to the meaning a word connotes. Methods: This dissertation aims to escape from such biased ideas and study the meaning of 'Pum-Jil品質' from the view of humanities and exegetics. Then the natural definition of the word as far as business administration is concerned can be considered. Results: 'Pum-Jil品質' has been used amid changes in modern times(historic texts in both Korea and China. In Korea particularly, the word was used in the royal court until comparatively modern times.), and now it is also widely used in the field of business administration. In this process of change, a notable point is that 'Pum-Jil品質', which was originally used to mean 'nature or character of a man', took on a new meaning, 'a certain quality of a thing or a good'. Conclusion: 'Pum-Jil品質' should require basic functional 'quality' of goods or services as a prerequisite. And the functional quality should meet consumers' needs, as the pledge (trust; 信賴) for quality is between suppliers and consumers. Without consumer's trust for goods, the relationship between suppliers and consumers cannot be maintained. So goods must exchange with trust, not expenses. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics.

• Journal of the Korean Vacuum Society
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• v.14 no.4
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• pp.207-214
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• 2005

This paper presents a channel structure for promising high performance pseudomorphic high electron mobility transistor(pHEMT) switching device for design and fabricating of microwave control circuits, such as switches, phase shifters, attenuators, limiters, for application in personal mobile communication systems. Using the designed epitaxial channel layer structure and ETRI's $0.5\mu$m pHEMT switch process, single pole double throw (SPDT) Tx/Rx monolithic microwave integrated circuit (MMIC) switch was fabricated for 2.4 GHz and 5 GHz band wireless local area network (WLAN) systems. The SPDT switch exhibits a low insertion loss of 0.849 dB, high isolation of 32.638 dB, return loss of 11.006 dB, power transfer capability of 25dBm, and 3rd order intercept point of 42dBm at frequency of 5.8GHz and control voltage of 0/-3V These performances are enough for an application to 5 GHz band WLAN systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.220-220
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• 2013

Surface-normal transmission electro-absorption modulator (EAM) are attractive for high-definition (HD) three-dimensional (3D) imaging application due to its features such as small system volume and simple epitaxial structure [1,2]. However, EAM in order to be used for HD 3D imaging system requires uniform modulation performance over large area. To achieve highly uniform modulation performance of EAM at the operating wavelength of 850 nm, it is extremely important to remove the GaAs substrate over large area since GaAs material has high absorption coefficient below 870 nm which corresponds to band-edge energy of GaAs (1.424 eV). In this study, we propose and experimentally demonstrate a transmission EAM in which highly selective backside etching methods which include lapping, dry etching and wet etching is carried out to remove the GaAs substrate for achieving highly uniform modulation performance. First, lapping process on GaAs substrate was carried out for different lapping speeds (5 rpm, 7 rpm, 10 rpm) and the thickness was measured over different areas of surface. For a lapping speed of 5 rpm, a highly uniform surface over a large area ($2{\times}1\;mm^2$) was obtained. Second, optimization of inductive coupled plasma-reactive ion etching (ICP-RIE) was carried out to achieve anisotropy and high etch rate. The dry etching carried out using a gas mixture of SiCl4 and Ar, each having a flow rate of 10 sccm and 40 sccm, respectively with an RF power of 50 W, ICP power of 400 W and chamber pressure of 2 mTorr was the optimum etching condition. Last, the rest of GaAs substrate was successfully removed by highly selective backside wet etching with pH adjusted solution of citric acid and hydrogen peroxide. Citric acid/hydrogen peroxide etching solution having a volume ratio of 5:1 was the best etching condition which provides not only high selectivity of 235:1 between GaAs and AlAs but also good etching profile [3]. The fabricated transmission EAM array have an amplitude modulation of more than 50% at the bias voltage of -9 V and maintains high uniformity of >90% over large area ($2{\times}1\;mm^2$). These results show that the fabricated transmission EAM with substrate removed is an excellent candidate to be used as an optical shutter for HD 3D imaging application.