• 제목/요약/키워드: H.235

검색결과 480건 처리시간 0.031초

Hardening Properties of Activated Calcium Dialuminate Clinker with Phosphoric Acid Solution

  • Song, Tae-Woong;Kim, Sei-Gi
    • The Korean Journal of Ceramics
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    • 제3권4호
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    • pp.235-238
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    • 1997
  • Basic properties of new cement pastes based on the system $CaO-Al_2O_3-P_O_5-H_2O$were studied Phosphoric acid solutions and calcium dialuminate clinkers synthesized by the hydration-burning method were used for liquid and powder components of the paste, respectively Variation in the compositions of the paste was achieved by changing the liquid/powder ratio and the concentration of phosphoric acid solution. The hardening rate of the paste was so largely affected by the amount of phosphoric acid that hardening was inhibited with the low-concentrated solution but was explosively accelerated with the high-concentrated solution. The phosphoric acid solutions of concentration of 45~50% and the liquid/powder ratio of 0.5~1.5 were favoured for the high early-strength cement paste with the reasonable hardening rate and high strength. The binding phase of hardened paste was the dense amorphous gel of the system $CaO-Al_2O_3-P_O_5-H_2O$. in which the unreacted calcium dialuminate grains were embeded.

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Back-Propagation 신경 회로망을 이용한 비선형 시스템의 자기 학습 제어 (Self-learning control of nonlinear system using Back-propagation neural networks.)

  • 박철영;송호신;이준탁;박영식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.231-235
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    • 1992
  • A new algorithm is proposed to identify the structure and the parameters of the nonlinear discrete-time plant with only the unknown dynamics and the weak informations about its structure. The proposed algorithm is constructed with the compensation method of weghing values using its previous derivatives and with the efficient technique updating self-learning coefficients. The result in this application is thought to prove the effectiveness of the algorithm proposed in this paper and its superiority to the conventional ones.

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정지궤도 위성의 열해석 모델 보정 (THERMAL MODEL CORRELATION OF A GEOSTATIONARY SATELLITE)

  • 전형열;김정훈
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2011년 춘계학술대회논문집
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    • pp.230-235
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    • 2011
  • COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and was developed by KARI for communication, ocean and meteorological observations. COMS was tested under vacuum and very law temperature conditions in order to correlate thermal model and to verify thermal design. The test was performed by using KARI large thermal vacuum chamber. The COMS S/C thermal model was successfully correlated versus the 2 thermal balance test phases. After model correlation, temperatures deviation of all individual unit were less than $5^{\circ}C$ and global deviation and standard deviation also satisfied the requirements, less than $2^{\circ}C$ and $3^{\circ}C$. The final flight prediction was performed by using the correlated thermal model.

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유한요소해석을 통한 전기 커넥터의 압착 품질 향상 (Quality Improvement for Crimping Process of Electrical Connector Using FEM Analysis)

  • 윤철호;박진기;최현순;김영석
    • 소성∙가공
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    • 제18권3호
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    • pp.229-235
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    • 2009
  • This paper covers finite element simulations to evaluate the terminal crimping process of automobile electrical connector. Crimping is a classical technology process to ensure the electrical and the mechanical link between a wire and a terminal. Numerical modeling of the process is helpful to choose and to optimize the dimensions of the crimping part of the connector. In this paper, we discuss a 2D simulation of the crimping process, using explicit finite element methods (ABAQUS/Explicit) and we compare the results with experimental data from the industrial process of crimping (crimping height, crimping width and compressibility). The explicit method is preferred for the modeling of multi-contact problems, in spite of the quasi-static process of crimping. As compared with CAE analysis, a performance improvement makes certain of the truth of the matter.

Bi-arc법을 이용한 평면 캠의 정밀 가공 기술에 관한 연구 (A Study on Precision Machining Technology for Disk Cams using Bi-arc Method)

  • 신중호;권순만;조인영;김종찬;강한성
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.235-236
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    • 2006
  • The disk cam mechanism can produce a positive motion with relatively few components. This paper introduce a shape design of cam using the relative velocity method and a precision machining technology for using Bi-arc method. The paper gives a machining information at each point using the Bi-arc method and the analysis method of the cutting error due to the moving path of the cutter, so that we can lead to the optimum design in a disk cam mechanism.

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Antitumor and Antioxidant Activities of the Extracts from Fruiting Body of Phellinus linteus

  • Lee, June-Woo;Baek, Seong-Jin;Bae, Woo-Chul;Park, Jeong-Min;Kim, Yong-Seok
    • Mycobiology
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    • 제34권4호
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    • pp.230-235
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    • 2006
  • Fruiting bodies of Phellinus linteus were extracted by hot water and alkali methods. Sugar contents of PL-H (hot water extract) and PL-A (alkali water extract) were 81.1%, 37.4% and protein contents were 6.2%, 21.8%, respectively. Amino acid pattern showed that two extracts contained large amount of aspartic acid and alanine. Two extracts showed characteristic IR absorption pattern for glycosidic bond at $890\;cm^{-1}$. PL-H was divided two fractions by gel filtration chromatography and the molecular weights of each fraction were estimated to be about 10 kD and 225 kD, respectively and also PL-A was estimated 10 kD. Two extracts showed strong antitumor, immunomodulating and antioxidant activities, and were compared with commercialized glycopeptide anticancer drugs.

Species Dependence of Neurofilament Structures: Monte Carlo Simulation studies of Residue-Based Neurofilament Models

  • 김선옥
    • EDISON SW 활용 경진대회 논문집
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    • 제3회(2014년)
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    • pp.225-235
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    • 2014
  • 6종의 Intermediate filament 중 type IV인 Neurofilaments (NFs)는 신경세포에 존재하는 세포골격세사로 heavy NF(NF-H), medium NF(NF-M), light NF(NF-L) 세가지의 분자 질량 단백질로 구성되어 있다. NF의 side arm은 interfilament spacing과 axonal caliber를 조절하는 중요한 역할을 한다고 생각되어왔다. 또한 이에 대해서 각각의 protein의 역할은 알아내기 위해 isolated NF의 형태와 구조에 대해 많은 연구가 이루어졌는데, NF의 구조적 특성은 NF sidearm의 tail 부분에서 phosphorylation의 정도에 따른 Lys-Ser-Pro(KSP) repeats의 charge distribution을 통해 알 수 있다. 지금까지 NF에 대한 많은 연구가 이루어졌지만 인간에 한해서만 진행되었다. 그렇기 때문에 본 연구에서는 주어진 amino acid sequence와 각 species의 NF-H:NF-M:NF-L의 비율의 정보를 이용하여 The constant-NVT ensemble MC simulation을 통해 인간뿐만이 아닌 다른 species에 대한 NF의 구조적 특성을 알아보고자 한다.

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2분할 전류유입 공진 회로를 이용한 PFC회로의 설계 (Design of the Circuit for a Power Factor Correction using the Two-Input Current Resonant)

  • 장우신;고강훈;서기영;이현우;곽동걸
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.233-235
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    • 2001
  • On the active filter converter for power factor correction is used inverter for a air-conditioner's power supply to meet IEC standard In the active filter topology for power factor correction, extra switch only control the input current indirectly to satisfied with the IEC standard for reducing the cost and size. In this paper, by dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be canceled between the two modes. Hence, the harmonics characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theoretical and experimental implementations.

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H 의원 실내디자인을 위한 대안 및 적용에 관한 연구 (A Study on the Alternatives and Application for H clinic interior design)

  • 박상현;신인선
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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    • pp.235-236
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    • 2005
  • Recently the small medical clinics designed well are appearing even in the small and medium city. Especially in the rural area, these clinics have the role not only as medical facilities but also as community place for their fellowship. This project was launched by order of a female doctor, an otolaryngologist. Her order is focused on otolaryngology but I also proposed the design alternatives such as plastic surgery and dental surgery clinic designed under the same conditions. This project was also related with the classwork of interior architecture course of our faculty and I tried to let the students understand the relation between theory and practice. The design goal was to join together harmoniously two stories which were completely separated and I consistently concentrated on the expression of immateriality and superimposition of space.

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가정용 하이브리드 배전시스템에 대한 연구 (The Study on Residential Hybrid Distribution System)

  • 변병주;서현욱;이영진;최중묵;김승열;김동진;최규하
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2012년도 전력전자학술대회 논문집
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    • pp.234-235
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    • 2012
  • 본 연구는 가정에서 사용하는 부하는 IT 직류 부하가 증가함에 따라서 기존의 배전망이 내재하고 있는 변환 손실을 줄이고자 직류와 교류를 동시에 사용하는 Hybrid 배전을 적용하여 실제 데이터 분석을 통하여 Hybrid 배전시스템에 대한 연구하였다.

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