• 대한금속재료학회지
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• 제49권5호
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• pp.362-366
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• 2011

Aluminosilicate inorganic polymer binder has been studied as an alternative to ordinary Portland cement due to its higher physical properties, chemical resistance and thermal resistance. This study has been carried out in an attempt to understand the hardening characteristics of aluminosilicate binder by varying the content of calcium. Samples with four different ratios of Al, Si, and Ca were synthesized in this study with the Al:Si:Ca mol ratio being 1.00:1.85~1.98:0.29~2.12. Furthermore, an alkali silicate solution was prepared with the sodium hydroxide (NaOH) and sodium silicate (NaSi). The hardening characteristics of the specimens were analyzed using XRD, SEM, and TG/DTA. In addition, compressive strength and sintering time of specimens were measured as a function of calcium content. The results showed that the specimen containing 2.12 mol% calcium offered the highest compressive strength. However, the compressive strength of the specimen containing 0.26 mol% calcium was lower relative to the other specimens. The results displayed a distinct tendency that as more calcium was added to the inorganic polymer, setting time became shorter. When calcium was added to the inorganic polymer structure, a second phase was not formed, indicating that the addition of calcium does not affect the crystalline structure.

• Fisheries and Aquatic Sciences
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• 제25권3호
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• pp.158-166
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• 2022

The complete mitochondrial genome of Tremoctopus violaceus was sequenced to analyze its organization and phylogenetic status within the order Octopoda. The mitochondrial genome of T. violaceus had a structure and organization similar to that of other Octopoda. The content of the nucleotides A, C, G, and T was 31.68 %, 7.71 %, 20.02 %, and 40.58 %, respectively. All protein-coding genes (PCG) began with the ATG codon, excluding ND4 and ATP6, which began with ATC and ATT, respectively, and terminated with TAG, TAA, TA, or T. Codons for isoleucine were the most used codons, whereas those for arginine were used the least. Two extra tRNAs, trnN and trnL, were found in the control region. These tRNAs have a D-armless structure. The control region had excess A + T content (83.16 %) and a stem-loop structure with two elements, which is reported for the first time in Octopoda by our study. Bayesian inference using 13 PCG revealed that Octopus and Octopodidae were polyphyletic, and that Tremoctopodidae diverged relatively earlier within Octopoda. The mitochondrial genome of T. violaceus and its characteristics may help to understand the evolutionary history of Octopoda and establish a marine biodiversity conservation strategy.

• 한국세라믹학회지
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• 제34권5호
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• pp.528-534
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• 1997

There have been many studies on the preparation of slip, forming and drying in the slip casting process. However, is has not been yet on the rheological properties of consolidated body which largely affect on the workability. It was investugated that the rheological properties of the consolidated bodies formed by slip casting in the form of cakes from well dispersed(slip C) and weakly agglomerated slip(slip B) in the clay and clay-fly ash systems. The state of dispersion of slip was found to affected the critical moisture content which was largely affected by the pore and moisture distribution of the consolidated body. The cake C show lower critical moisture content than cake B in the clay system. However, the cake B gives lower critical moisture content than cake C in the clay-fly ash system.

• The Korean Journal of Ceramics
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• 제6권1호
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• pp.68-73
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• 2000

The effects of oxygen annealing on the carbon content in MgO thin films were investigated, MgO thin films were deposited on Si(100) substrate at different temperatures of 400 to $700^{\circ}C$ and different deposition rates of 3.4 to 11.6$\AA$/min. Using rf magnetron sputtering method. Carbon content change on the surface of MgO thin films with the oxygen annealing at different temperatures was investigated using various method. The carbon content decreased as the annealing temperature increased. $Pb(Zr_{0.53}Ti_{0.47})O_3$(PZT) thin films were deposited on the MgO/Si(100) substrates. The effects of carbon content on the phase formation and the electrical properties of PZT thin films were also investigated.

• ETRI Journal
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• 제34권4호
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• pp.583-590
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• 2012

In this paper, we present a new approach for speaker diarization. First, we use the prosodic information calculated on the original speech to resynthesize the new speech data utilizing the spectrum modeling technique. The resynthesized data is modeled with sinusoids based on pitch, vibration amplitude, and phase bias. Then, we use the resynthesized speech data to extract cepstral features and integrate them with the cepstral features from original speech for speaker diarization. At last, we show how the two streams of cepstral features can be combined to improve the robustness of speaker diarization. Experiments carried out on the standardized datasets (the US National Institute of Standards and Technology Rich Transcription 04-S multiple distant microphone conditions) show a significant improvement in diarization error rate compared to the system based on only the feature stream from original speech.

• 한국구조물진단유지관리공학회 논문집
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• 제7권1호
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• pp.259-266
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• 2003

Recently, the premature corrosion for reinforced concrete structure exposed to chloride bring about a serious problem in concrete structures. Specially, the concrete structures of sea coast are exposed much to chloride which make rapid corrosion. Thus, construction activities and maintenances for marine facilities are more demanded than those for land structures. The results of this study have been analysed to identify the extent of chloride content and incidence of carbonation for construction age. After measuring chloride content in concrete, it was conclued that about 90% of all tests on concrete samples exceed the acceptable maximum limit to risk of chloride-induced carbonation. The carbonation rate coffnient by age of train structures in the east eatimated 6. 55, 4.76 grater than 3. 727. In the basis of this result, it is necessary to maintenance for the important train facilities with the regular tests of chloride and carbonation.

• 한국세라믹학회지
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• 제45권11호
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• pp.675-680
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• 2008

The effect of pore former content on both porosity and pore structure was investigated for porous sintered reaction-bonded silicon nitrides (SRBSNs). A spherical PMMA with $d_{50}=8{\mu}m$ was employed as a pore-former. Its amount ranged from 0 to 30 part. Porous SRBSNs were fabricated by post-sintering at various temperatures where the porosity was controlled at $12{\sim}52%$. The strong tendency of increasing porosity with PMMA content and decreasing porosity with sintering temperature was observed. Measured pore-channel diameter increased $(0.3{\rightarrow}1.1{\mu}m)$ with both PMMA content and sintering temperature.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2016년도 제53차 동계학술대회논문집 24권1호
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• pp.219-222
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• 2016

블록형 구조물의 구축은 완구의 목적으로 널리 사용되고 있으며 이외에도 제품 디자인을 위한 래피드 프로토타이핑 및 창의학습을 위한 도구로도 활용되고 있다. 본 논문은 블록형 구조물을 적은 비용으로 손쉽게 설계하고 구축하기 위하여 블록형 구조물 자동 생성 기능 및 편집 기능을 제공하는 소프트웨어 시스템을 개발하였다. 본 시스템을 이용하여 가상공간에서 자유롭게 블록형 구조물을 생성 및 편집할 수 있고, 실제 구조물의 조립을 위한 매뉴얼로 활용할 수 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.277-280
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• 2004

Recently, as structure is more higher and bigger, we need high strength and high performance concrete. Therefore it is necessary superplasticizer for high strength and high performance concrete. In this study, it is examined the properties of flow, air content and strength of concrete with polycarboxylate superplasticizer in comparison with existing superplasticizer. First, The slump loss of concrete used polycarboxylate superplasticizer showed 2cm until 120 minutes. Second, The air content loss of concrete used polycarboxylate superplasticizer showed $1\%$ until 120 minutes. Third, It is possible to manufacture $1000kgf/cm^2$ strength concrete using polycarboxylate superplasticizer with $806kg/m^3$ cement content, $18\%$ water-binder ratio, $15\%$ silica fume, $10\%$ fly-ash content.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.232-233
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• 2013

The unit-water content in fresh concrete determines consistency, and play an important role in condensing the structure of concrete and enhancing the durability of concrete. The capacitance measurement method measure quickly unit-water content and is the best way to apply to construction site. In this study, the unit-water content of capacitance measurement method is estimated according to types and replacemment ratio of admixture. and the field application of capacitance measurement method is reviewed.