• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.98-104
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• 1987

Studies were carried out to determined the optimal conditions of processing and changes in trypsin indigestible substrate(TIS) and in vitro protein digestibility of paddy grasshopper(Oxya chinensis formosana) under various drying conditions. The multienzyme assy and amino acid compositions were used to predict the quality changes of dried products. The in vitro protein digestidility of defatted products were higher than that of sun and hot air dried products. This results indicated that heat processing is decreased the digestibility, but is increased the TIS contents of dried samples. Amino acid composition of the products was comparable to the ANRC casein scoring pattern. The protein was espeoially low in the amount of lysine, tryptophan and methionine, but high in the quantity of aspartic acid, glutamic acid and arginine indicating that it could be a difference of the dry processing. C-PER and DC-PER were 2.65 and 2.44, respectively, in the defatted and freeze dried products and 2.49 and 2.30, respectively, in hot air dried products. From the these results, it could be confirmed that defatted and freeze dried products might be utilized with feed or foodstuff, unless the toxic substances were no longer detectable.

• Journal of IKEEE
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• v.23 no.2
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• pp.743-746
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• 2019

In this paper we proposed a new ocean radiation automatic monitoring system. The proposed system has the following characteristics: First, using NaI + PVT mixed detectors, the response speed is fast and precision analysis is possible. Second, the application of temperature compensation algorithm to scintillator-type sensors does not require additional cooling devices and enables stable operation in the changing ocean environment. Third, since cooling system is not needed, electricity consumption is low, and electricity can be supplied reliably by utilizing solar energy, which can be installed at the observation deck of ocean environment. Fourth, using GPS and wireless communications, accurate location information and real-time data transmission function for measurement areas enables immediate warning response in the event of nuclear accidents such as those involving neighboring countries. The results tested by the authorized testing agency to assess the performance of the proposed system were measured in the range of $5{\mu}Sv/h$ to 15mSv/h, which is the highest level in the world, and the accuracy was determined to be ${\pm}8.1%$, making normal operation below the international standard ${\pm}15%$. The internal environmental grade (waterproof) was achieved, and the rate of variation was measured within 5% at operating temperature of $-20^{\circ}C$ to $50^{\circ}C$ and stability was verified. Since the measured value change rate was measured within 10% after the vibration test, it was confirmed that there will be no change in the measured value due to vibration in the ocean environment caused by waves.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.458-464
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• 2006

The Pd-Ni-Ag alloy composite membrane using modified porous stainless steel (PSS) as a substrate was prepared by a electroless plating technique. In this work, we have introduced the intermediate layer between Pd-based alloy and a metal substrate. As an intermediate layer, the mixtures of nickel powder and inorganic sol such as $SiO_{2}$ sol, $Al_{2}O_{3}$ sol, and $TiO_{2}$ sol were used. The intermediate layers were coated onto a PSS substrate according to various membrane preparation conditions and then $N_{2}$ fluxes through the membranes with different intermediate layers were measured. The surface morphology of the intermediate layer in the mixture of nickel powder and inorganic sol was analyzed using scanning electron microscope (SEM). Finally, the Pd-Ni-Ag alloy composite membrane using the support coated with the mixture of nickel powder and silica as an intermediate layer was fabricated and then the gas permeances for $H_{2}$ and $N_{2}$ through the Pd-based membrane were investigated. The selectivity of $H_2/N_2$ was infinite and the $H_{2}$ flux was $1.39{\times}10^{-2}mol/m^2{\cdot}s$ at the temperature of $500^{\circ}C$ and trans-membrane pressure difference of 1 bar.

• Korean Journal of Heritage: History & Science
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• v.51 no.4
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• pp.108-119
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• 2018

"The Collection of Yi Chungmugong" manuscript is a hand-written manuscript of the volume 1 consisting of the Collection, published in 1795 and it seems to have completed the contents of the book by correcting the first part of the book before print. The book adopted a form of Seonjangbon(線裝本) of Ochimanjeongbeop(五針眼訂法) and was urgently needed some measures to preserve because it has been much damaged by stains, loss and oxidation due to moisture on the bottom of it. In addition, a scientific investigation was applied to find out the features of the quality of paper and fiber used for the book, which would be reflected in the process of the preservation. The characteristics of paper were measurmented for size(cm), thickness(mm), weight(g), basis weight($g/m^2$), density($g/cm^3$), chain line and laid lines($3{\times}3cm$). The measurement showed that the characteristics of paper used in royal books published in the late Joseon Dynasty. For the paper-fiber of the book, C stain was used and the technique revealed that the book is made of bast fibre of paper mulberry and its binding strings are cotton. SEM-EDS analysis was performed to verify the existence of additives in paper. As a result of the analysis, The crystallized calcium was detected in addition to the main components carbon(C) and oxygen(O). This artifact is the unique final version of "The collection of Yi Chungmugong", which has considerable value in terms of academic research, besides it helps to understand how to print books of Joseon Dynasty. And it also has a very accurate information of when and where the book was made, which primarily could be resources to conserve and restore for other book heritage.

• Journal of Biomedical Engineering Research
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• v.21 no.3 s.61
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• pp.273-277
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• 2000

The galvanostatic anodization of commercially Pure titanium plate (c.p.Ti, grade 2) was investigated in various concentrations of aqueous $H_3PO_4$ from 0.05M to 0.7M. The surfaces of anodic oxide films, formed by the current density in the range between 0.3 and $l.0 A/dm^2$. were analyzed by SEM and XRD. The voltage-time (V-T) curves displayed an initial linear part and a subsequent parabolic part, and the initial slopes increased with an increase in the current density in 0.05M $H_3PO_4$. As the concentration of the electrolyte increased, the V-T corves exhibit no change but the final voltage decreased. The anodic oxide film of titanium developed from fine grains to snowflake-like grains in a layered structure with an increase in the concentration of the electrolyte and current density. Sparking at the interface of the oxide/electrolyte accompanied the local deposition and dissolution of the oxide film through discharging. The crystallinity of the anodic oxide film increased with the anodizing voltage and decreased with an increase in the concentration of the electrolyte.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.71-80
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• 2001

To understand paleoceanographic environmental changes in the Esat Sea during the transitional period between Holocene and last glacial maximum, geochemical high resolution study was conducted by using a piston core(95PC-1) samples collected from the southernmost part of the Ulleung Basin. Geochemical results reveal that major distinctive paleoceanographic variations in transitional period are prominent. Major elemental concentrations show distinctive variations between glacial and Holocene suggesting changes in sediment supply. $TiO_2/Al_2O_3$ ratio of the sediment indicates different sediment composition between Holocene and glacial period. The content of total organic carbon ranging from 0.5% to 4% during transitional period. These vslues showed 2-4 times and two times higher than those of last glacial and Holocene, respectively. The C/N ratios deduced from organic matters exceed10 during transitional period suggesting terrigenous organic matter are supplied from continent, especially during last glacial maximum. Carbonate contents are relatively stable during Holocene and last glacial maximum with gradual decrease during glacial period with high fluctuation during transitional period. The variations of chemical index of weathering (CIW) also show a distinctive variation between glacial and Holocene, which is coincident with those of carbonate and organic carbon. The grain size distribution indicates that the difference content of silt fraction during Holocene and glacial period is closely related with climatic effect during glacial period. Therefore geochemical differences in sediment composition between Holocene and last glacial maximum is thought to be related to paleoceanographic, sea-level change and local paleoclimatic changes.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.46-52
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• 2009

Statement of problem: Recently, titanium has become popular as superstructure material in implant dentistry because titanium superstructure can be easily milled by means of computer-aided design and manufacture (CAD/CAM) technique. But retention form such as nail head or bead cannot be cut as a result of technical limitation of CAD/CAM milling and bond strength between titanium and porcelain is not as strong as that of conventional gold or metal alloy. Purpose: The objective of this study was to evaluate the shear bond strength of three different materials: heat curing resin, composite resin, porcelain which were bonded to grade II commercially pure Titanium (CP-Ti). Material and methods: Thirty seven CP-Ti discs with 9 mm diameter, 10 mm height were divided into three groups and were bonded with heat curing resin (Lucitone 199), indirect composite resin (Sinfony), and porcelain (Triceram) which were mounted in a former with 7 mm diameter and 1 mm height. Samples were thermocycled for 1000 cycles at between $5-55^{\circ}C$. Shear bond strength (MPa) was measured with Instron Universal Testing Machine with cross head speed of 1 mm/min. The failure pattern was observed at the fractured surface and divided into adhesive, cohesive, and combination failure. The data were analyzed by one-way ANOVA and Scheffe's multiple range test (${\alpha}=0.05$). Results: Lucitone 199 ($17.82{\pm}5.13\;MPa$) showed the highest shear bond strength, followed by Triceram ($12.97{\pm}2.11\;MPa$), and Sinfony ($6.00{\pm}1.31\;MPa$). Most of the failure patterns in Lucitone 199 and Sinfony group were adhesive failure, whereas those in Triceram group were combination failure. Conclusion: Heat curing resin formed the strongest bond to titanium which is used as a CAD/CAM milling block. But the bond strength is still low compared with the bond utilizing mechanical interlocking and there are many adhesive failures which suggest that more studies to enhance bond strength are needed.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1723-1725
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• 1999

This paper is the study for piezoelectric properties of PMN-PT-PZ composition for high power piezoelectric device. It needs the properties such as high mechanical quality factor(Qm), high electromechanical coupling coefficient(kp) and high dielectric strain constant$(d_31)$, and the stable electromechanical properties under high vibration level. For acquiring this results, the value of x is changed in 0.1Pb$(Mn_{1/3}Nb_{2/3})O_3$+(0.9-x)$PbZrO_3+xPbTiO_3$ composition to find MPB(morphotropic phase boundary), and the piezoelectric constants is measured by resonance-antiresonance frequency method, based on IRE Standard. Also, it is measured as a function of the amount of additive, $Nb_2O_5$. When the composition is applied to high power device, the electromechanical properties is measured by laser vibrometer to confirm the reliablity under high vibration level. From these results, PMN-PT-PZ composition is shown excellent properties and capacity of application to high power device.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.255-255
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• 2015

국제핵융합실험로(ITER)의 3대 목표 중 하나는 핵융합로 개발을 위한 삼중수소증식블랑켓 개념을 시험하고 검증하는 것이며, 이를 위해 시험증식블랑켓(TBM, Test Blanket Module) 프로그램을 마련, 각국이 참여할 수 있도록 하고 있다. 한국도 2012년 국가핵융합위원회 결정에 따라, EU, 일본, 중국, 인도와 함께 TBM 프로그램에 참여하고 있으며, 2021년 설치를 목표로 헬륨냉각 고체증식재 개념의 HCCR (Helilum Cooled Ceramic Reflector) TBM을 설계, 개발하고 있다. 한국형 TBM은 총 4개의 서브모듈과 하나의 후벽(Back Manifold, BM) 으로 구성되며, 각 서브모듈은 플라즈마와 대면하는 일차벽(First Wall, FW), 증식재와 증배재, 반사재를 담고 있는 증식영역(Breeding Zong, BZ), 냉각재 매니폴드 및 구조물 역할을 하는 측벽(Side Wall, SW) 등의 기능부품으로 구성되어 있다. 냉각재는 8 MPa, $300-500^{\circ}C$의 고온고압헬륨을 사용하고, Li2SiO4 혹은 Li2TiO4 형태의 Li 세라믹 증식재를 사용하며, 중성자 증배를 위해 Be 증배재 및 흑연 반사재를 사용한다 [1-3]. 2015년 2월 개념설계검토(CDR, Conceptual Design Review)를 위해, TBM-shield를 포함한 TBM-set 설계가 완료되었으며, 열수력, 구조, 지진, 전자기, 복합하중에 대한 평가가 진행되었다. 본 논문에서는 이 중 H/He-phase에 시험될 EM-TBM과 D-T phase에 시험될 INT-TBM에 대한 열수력 성능 결과를 소개하였다[5]. 각각의 열부하 조건은 0.17과 $0.3MW/m^2$이며, 중성자 조사는 D-T phase 에서만 고려되었다. 구조재 및 사용된 기능소재별 온도 요건을 정의하고, 성능해석 결과와 비교하였으며, 이를 통해 모든 온도 요건을 만족함을 최종 확인하였다. 이러한 온도 분포는 열응력 평가를 위해 구조해석 입력자료로 활용되었다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1587_1588
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• 2009

In this paper, PCB embedded balanced-to-unbalamced duplexer using coupled LC resonator was introduced for low cost dualband WiMax front-end-module application. In order to obtain the function of bandpass filter and balun transformer, proposed duplexer was configured by using magnetically coupled LC resonator. Out-of-band suppression was enhanced by applying two m-Derived transform circuits to obtain transmission zeros at 2GHz and 4.8GHz. In order to reduce the size of embedded duplexer, BaSrTiO3 (BST) composite high Dk RCC film was applied to improve the capacitance density. This high Dk film provided the capacitance density of 12.2 pF/mm2. The simulation results shows that fabricated duplexer had an insertion loss of 2.9dB and 5.5dB and return loss of 15dB and 16dB for 2.5GHz~2.6GHz and 3.5GHz~3.6GHz, respectively. The maximum magnitude and phase imbalance were 0.01dB and 0.17dB, and 1degree and 2degree in its passband, respectively. The out-of-band suppression was observed approximately 29dB and 40dB below 1.9GHz and over 4.5GHz, respectively. It has a volume of 6 mm $\times$ 7 mm $\times$ 0.7 mm (height).