• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1605-1608
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• 2004

Single phase $CuInS_2$ thin film with a highest diffraction peak (112) at a diffraction angle ($2{\theta}$) of 27.7$^{\circ}$ was well made by SEL method at annealing temperature of 250 $^{\circ}C$ and annealing hour of 60 min in vacuum of $10^{-3}$ Torr or in S ambience for an hour. And the peak of diffraction intensity at miller index (112) of $CuInS_2$ thin film annealed in S ambience was shown a little higher about 11 % than in only vacuum. Single phase $CuInS_2$ thin films were appeared from 0.85 to 1.26 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated in S ambience were all over 50 atom%. Also when Cu/In composition ratio was 1.03, $CuInS_2$ thin film with chalcopyrite structure had the highest XRD peak (112). And lattice constant a and grain size of the thin film in S ambience were appeared a little larger than those in only vacuum. The largest lattice constant of a and grain size of $CuInS_2$ thin film in S ambience was 5.63 ${\AA}$ and 1.2 ${\mu}$m respectively. And the films in S ambience were all p-conduction type with resistivities of around $10^{-1}{\Omega}cm$.

• The Korean Journal of Ceramics
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• 제3권2호
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• pp.116-123
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• 1997

A chemically stabilized $\beta$-cristobalite, which is stabilized by stuffing cations of $Ca^{2+}$ and $Al^{3+}$, was prepared by a solution-polymerization route employing Pechini resin or PVA solution as a polymeric carrier. The polymeric carrier affected the crystallization temperature, morphology of calicined powder, and particle size distribution. In case of the polyvinyl alcohol (PVA) solution process, a fine $\beta$-cristobalite powder with a narrow particle size distribution (average particle size : 0.3$\mu\textrm{m}$) and a BET specific surface area of 72 $\m^2$/g was prepared by an attrition-milling for 1 h after calcination at 110$0^{\circ}C$ for 1h. Wider particle size distribution and higher specific surface area were observed for the $\beta$-cristobalite powder derived from Pechini resin. The cubie(P1-to-tetraganalb) phase transformation in polynystalline $\beta$-cristobalite was induced at approximately 18$0^{\circ}C$. Like other materials showing transformation toughening, a critical size effect controlled the $\beta$-to-$\alpha$ transformation. Densifed cristobalite sample had some cracks in its internal texture after annealing. The cracks, occurred spontaneoulsy on cooling, were observed in the sample with an average grain sizes of 4.0 $\mu\textrm{m}$ or above. In case of the sintered cristobalite having a composition of CaO.$2Al_2O_3$.40SiO$_2$, small amount of amorphous phase and slow grain growth during annealing were observed. Shear stress-induced transformation was also observed in ground specimen. Cristobalite having a composition of CaO.2Al2O3.80SiO2 showed a more sensitive response to shear stress than the CaO.$2Al_2O_3$.40SiO$_2$ type cristobalite. Shear-induced transformation resulted in an increase of volume about 13% in $\alpha$-cristobalite phase on annealing for above 10 h in the case of the former composition.

• 한국초지조사료학회지
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• 제33권3호
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• pp.177-184
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• 2013

This work was conducted to assess the use of Near-infrared reflectance spectroscopy (NIRS) as a technique to analyze nutritional constituents of Distillers dried grain with solubles (DDGS) and corn quickly and accurately, and to apply an NIRS-based indium gallium arsenide array detector, rather than a NIRS-based scanning system, to collect spectra and induce and analyze calibration equations using equipment which is better suited to field application. As a technique to induce calibration equations, Partial Least Squares (PLS) was used, and for better accuracy, various mathematical transformations were applied. A multivariate outlier detection method was applied to induce calibration equations, and, as a result, the way of structuring a calibration set significantly affected prediction accuracy. The prediction of nutritional constituents of distillers dried grains with solubles resulted in the following: moisture ($R^2$=0.80), crude protein ($R^2$=0.71), crude fat ($R^2$=0.80), crude fiber ($R^2$=0.32), and crude ash ($R^2$=0.72). All constituents except crude fiber showed good results. The prediction of nutritional constituents of corn resulted in the following: moisture ($R^2$=0.79), crude protein ($R^2$=0.61), crude fat ($R^2$=0.79), crude fiber ($R^2$=0.63), and crude ash ($R^2$=0.75). Therefore, all constituents except for crude fat and crude fiber were predicted for their chemical composition of DDGS and corn through Near-infrared reflectance spectroscopy.

• Advances in materials Research
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• 제5권2호
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• pp.93-105
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• 2016

KNN-based ceramics modified with small amounts of $Bi_4Zr_3O_{12}$ (BiZ) has been synthesized using high-throughput experimentation (HTE). The results from X-ray diffraction show that for samples with base composition $(K_{0.5}Na_{0.5})NbO_3$ (KNN), the phase present changes from orthorhombic to pseudo-cubic with more than 0.2 mol% BiZ addition; for samples with base composition $(K_{0.48}Na_{0.48}Li_{0.04})(Nb_{0.9}Ta_{0.1})O_3$ (KNNLT), the phase present changes from a mixture of orthorhombic and tetragonal symmetry to pseudo-cubic with more than 0.4 mol % while for samples with base composition $(K_{0.48}Na_{0.48}Li_{0.04})(Nb_{0.86}Ta_{0.1}Sb_{0.04})O_3$ (KNNLST), the phase present is tetragonal with <0.3 mol% BiZ addition and transforms to pseudo-cubic with more dopant addition. The microstructures of the samples show that addition of BiZ decreases the average grain size and increases the volume of pores at the grain boundaries. The values of dielectric constant for KNN and KNNLT compositions increase slightly with BiZ addition while that for KNNLST decreases gradually with BiZ addition. The dielectric loss values are between 0.02 and 0.04 for KNNLT and KNNLST compositions while they are ~ 0.05 for KNN samples. The resistivity values increases with BiZ addition and values in the range of $10^{10}{\Omega}cm$ and $10^{12}{\Omega}cm$ are obtained. The piezoelectric charge coefficient ($d{^*}_{33}$) is highest for KNNLST samples and decreases gradually from ~400 pm/V to ~100 pm/V with BiZ addition.

• 한국작물학회지
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• 제21권1호
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• pp.87-91
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• 1976

개간지에서 대두를 재배함에 있어서 시비의 효과를 구명하기 위하여 개간지에는 10a당 N.P.K:4.10.8 kg의 시용구를 비롯하여 무비구를 포함한 6개 처리구를 설치하고 효과를 비교하고저 따로 숙전에다 N.P.K:4.10.8 kg의 시비구를 설치하여 수량과 성분함량을 조사한 결과를 요약하면 다음과 같다. 1. 개간지는 같은 수준의 시비에서도 숙전보다 청예수량이나 자실수량이 극히 적었고 자실의 단백질함량도 적었다. 2. 같은 개간지내에 있어서는 질소의 시용량이 많을수록 자실수량이 많았다. 3. 자실성분에 있어서 숙전은 단백질과 지방함량이 개간지보다 많았고 탄수화물은 개간지가 숙전보다 많은 경향이었다. 4. 개간지에 있어서 자실성분함량은 처리간에 유의성이 인정되지 않았다. 5. 수량과 밀접한 관계가 있는 100입중, 1주협수 간장 간중등은 자실수량과 정의 상관을 나타냈으며 1%수준의 유의성이 인정되었다.

• 한국토양비료학회지
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• 제25권4호
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• pp.357-363
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• 1992

본(本) 시험(試驗)은 1954년(年)부터 동일비료연용(同一肥料連用)이 토양(土壤)의 양분변동(養分變動) 양상(樣相) 및 생산력에 미치는 효과를 구명(究明)하기 위(爲)하여 실시(實施)한 시험(試驗)에서 생산된 현미중(玄米中)의 화학성분(化學成分)을 분석(分析)하고 이들 성분(成分)과 미질(米質)과의 관계(關係)를 검토(檢討)한 것으로 이를 요약(要約)하면 다음과 같다. 1. 질소유형별(窒素類型別) 현미중(玄米中)의 복백미(腹白米) 생성량(生成量)은 질소(窒素)를 유안(硫安)으로 시용(施用)한 삼요소구(三要素區)에서 가장 많았고 유안단용구(柳安單用區), 요소단용구(尿素單用區), 완전무비구(完全無肥區)의 순(順)으로 낮았다. 2. 삼요소(三要素)를 시용(施用)하고 규산(珪酸) 또는 석회(石灰)를 각각(各各) 시용(施用)하였거나 이들 규산(珪酸) 및 석회(石灰)를 혼용(混用)하였을 때에는 삼요소(三要素)만을 시용(施用)하였을 때보다 복백미(腹白米) 생성량(生成量)이 크게 감소(減少)되었다. 그 정도(程度)는 석회시용구(石灰施用區)보다 규산시용구(珪酸施用區)에서 유의(有意)한 감소(減少)를 보였다. 3. 삼요소(三要素)를 동일(同一)하게 시용(施用)한 후(後) 퇴비(堆肥)를 시용(施用)하였거나 각(各) 개량제(改良劑)를 퇴비(堆肥)와 혼합(混合) 처리(處理) 하였을 때에는 삼요소(三要素) 단용구(單用區)에 비(比)하여 현미중(玄米中)의 복백미(腹白米) 생성량(生成量)이 크게 증가(增加)하였다. 특(特)히 삼요소(三要素)＋석회(石灰)＋퇴비구(堆肥區)에서는 삼요소(三要素) 단용구(單用區)에 비(比)하여 2배이상(培以上)의 높은 복백미(腹白米)가 생성(生成)되었다. 4. 복백미(腹白米) 생성량(生成量)이 적은 구(區)에서는 질소유형별(窒素類型別) 및 삼요소처리구(三要素處理區) 공(共)히 현미중(玄米中)의 전질소함량(全窒素含量)이 낮았으며 이들 각(各) 처리중(處理中)에서도 복백미(腹白米) 생성량(生成量)이 많았던 구(區)에서는 현미중(玄米中)의 전질소함량(全窒素含量)도 높았다. 5. 현미중(玄米中) Mg/K비율(比率)이 낮을 수록 복백미(腹白米) 생성량(生成量)은 많아지는 경향(傾向)이었으며, $Mg/K{\cdot}N$비율(比率) 역시(亦是) 낮은 구(區)에서 복백미(腹白米) 생성량(生成量)이 많았다.

• 한국재료학회지
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• 제5권6호
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• pp.682-689
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• 1995

Mg-Zn합금계의 입자미세화를 위하여 0.5-6 wt.% 조성범위의 Cu 및 Si를 첨가하였다. 합 잉곳트는 4 $\times$ $10^{-4}$ Torr의 진공의 BN을 내벽에 바른 석영관내에서 제조하였다. 제조된 합금을 435$^{\circ}C$에서 8시간 용체화처리한 후 결정립크기와 경도를 측정하였다. 측정결과 Mg-6wt.%Zn합금의 입자미세효과는 Cu가 2wt.%첨가될때, Si은 1.5wt.%가 첨가될 때가 최적의 조건이었다. Mg-6wt.% Zn과 Mg-6wt.%Zn-2wt.%Cu 및 Mg-6wt.%Zn-1.5wt.%Si합금을 시효열처리하여 시효거동을 조사하였다. 입자미세화에 의한 경도증가효과는 Mg-Zn-Cu합금계에서 크게 나타났으며 시효에 의한 경도증가 효과는 Mg-Zn-또합금계에서 크게 나타났다.

• 한국재료학회지
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• 제29권11호
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• pp.684-689
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• 2019

Single crystals, which have complexed composition, are fabricated by solid state grain growth. However, it is hard to achieve stable properties in a single crystal due to trapped pores. Aerosol deposition (AD) is suitable for fabrication of single crystals with stable properties because this process can make a high density coating layer. Because of their unique features (nano sized grains, stress inner site), it is hard to fabricate single crystals, and so studies of grain growth behavior of AD film are essential. In this study, a $BaTiO_3$ coating layer with ${\sim}9{\mu}m$ thickness is fabricated using an aerosol deposition method on (100) and (110) cut $SrTiO_3$ single crystal substrates, which are adopted as seeds for grain growth. Each specimen is heat-treated at various conditions (900, 1,100, and $1,300^{\circ}C$ for 5 h). $BaTiO_3$ layer shows different growth behavior and X-ray diffraction depending on cutting direction of $SrTiO_3$ seed. Rectangular pillars at $SrTiO_3$ (100) and laminating thin plates at $SrTiO_3$ (110), respectively, are observed.

• 한국음향학회지
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• 제23권4호
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• pp.296-302
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• 2004

해저면 분류를 위한 음향실험을 2003년 5월 19일부터 23일까지 5일간 남해에서 실시하였다. 실험 해역은 해저 구성물질이 각기 다른 6개의 정점을 선정하였으며 5개의 주파수 (30, 50, 80, 100, 120 kHz)를 이용하여 해저면 반사 신호를 측정하였다. 지음향 인자의 측정은 피스톤 코어를 이용하여 해저 퇴적물 샘플을 채취 후 입도분석을 하였다. 측정된 결과는 퍼지 이론을 이용하여 정점별 해저 퇴적물을 분류하였다. 반사손실 모델로 구성된 입력 소속 함수를 이용하여 측정결과를 평가 후, 그 결과를 Wentworth 입자 크기를 이용하여 출력 가능하도록 구성하였다. 퍼지 이론을 이용한 해저면 분류 기법과 잘 일치하였으며, 퍼지 이론을 통한 해저면 분류 기법의 가능성을 확인하였다.

• 한국주조공학회지
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• 제8권3호
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• pp.271-281
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• 1988

Al-bronze has a good mechanical property, corrosion resistance and castability, so being highlighted for the new copper alloy. So, effects of alloy composition and cooling rate in the mechaincal properties and solidification behavior have been investigated. The results obtained are as follows; 1) Change in volume on solidification is larger in metal mold casting than in sand mold casting. And it decreases by the addition of Al. 2) The mechanical property in metal mold casting is superior to the one in sand mold casting, and the inclination is obvious up to 9% Al, after heat-treatment ($885^{\circ}C$, $1.5hrs\;{\rightarrow}\;W\;{\cdot}\;Q\;{\rightarrow}\;540^{\circ}C$, 3hrs) 3) By adding Al, the mechanical property is slightly increased up to 9% Al, Above 9% Al, it is increased rapidly, and is accelerated by adding Fe. 4) Cooling rate and hardness, and grain size and cooling rate are related as follows in the range of $1100^{\circ}C$ to $1200^{\circ}C$ pouring temperature. Grain size(${\mu}m$)=$929.6422{\times}cooling\;rate(^{\circ}C\;/\;sec)^{-0.51537}$ Hardness(BHN)=$765.45713{\times}grain\;size({\mu}m)^{-0.31058}$.