• 제목/요약/키워드: Paper powder

검색결과 944건 처리시간 0.025초

Optimization of Powder Core Inductors of Buck-Boost Converters for Hybrid Electric Vehicles

  • You, Bong-Gi;Kim, Jong-Soo;Lee, Byoung-Kuk;Choi, Gwang-Bo;Yoo, Dong-Wook
    • Journal of Electrical Engineering and Technology
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    • 제6권4호
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    • pp.527-534
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    • 2011
  • In the present paper, the characteristics of Mega-Flux$^{(R)}$, JNEX-Core$^{(R)}$, amorphous and ferrite cores are compared to the inductor of buck-boost converters for Hybrid Electric Vehicles. Core losses are analyzed at the condition of 10 kHz sine wave excitations, and permeability fluctuations vs. temperature and magnetizing force will be analyzed and discussed. Under the specifications of the buck-boost converter for 20 kW THS-II, the power inductor will be designed with Mega-Flux$^{(R)}$ and JNEX-Core$^{(R)}$, and informative simulation results will be provided with respect to dc bias characteristics, core and copper losses.

Barium titanate doping on superconducting perovskite YBCO

  • Soh, Deawha;Korobova, N.;Li, Ying-Mei;Cho, Yong-Joon;Kim, Tae-Wan
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2000년도 추계학술대회논문집
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    • pp.120-123
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    • 2000
  • This paper reports a newly developed sol-gel process to synthesize dense YBCO thick films with BaTiO$_3$additives using electrophoretic deposition and metal alkoxide sol/particle suspension, which we successfully produce dense $YBCO+BaTiO_3$ ceramics at a rather low temperature, compared with the sintering temperature used in conventional methods. The thick films of HTS were prepared by electrophoretic deposition, using pre-sintered powder with barium titanate addition in the form of $BaTi(OR)_6$ solution in suspension for electrophoresis. The conditions for applied voltage and deposition times for electrophoretic deposition of HTS thick films were studied in detail.

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이종병렬기계생산의 일정계획지원 시스템 (A Scheduling Support System for Non-identical Parallel Machine Lines)

  • 정남기;정민영
    • 경영과학
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    • 제17권2호
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    • pp.67-73
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    • 2000
  • This paper describes a scheduling support system for a plant where the machine environment may be modeled as non-identical parallel machine lines (NPML). That is, there are a number of stages in series with various different-capability-machines at each stage. Arriving continuously are jobs with their specific due dates, processing times and candidate processing machines. We’ve developed a real-time scheduling module in conjunction with a supporting production information system which supplies necessary data to the module. This scheduling module is one of the 9 modules in this system, and is composed of both a scheduling interface and a production monitoring interface. This module allows users to generate many candidate schedules by selecting their business policies. The selective arguments which are available consist of allocation costs, batch sizes and machine selection intervals. They are now being implemented at a powder metallurgy plant.

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A Study on the Surface Modification of the Super Alloy by Plasma Transferred Arc Overlay Welding Method

  • Kim, Young-Sik;Lim, Chang-Hoon;Hwang, Won-Seok;Choi, Young-Gook
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권7호
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    • pp.852-856
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    • 2007
  • The Plasma Transferred Arc(PTA) overlay welding method is lately introduced as one of the most useful surface overlay method of the engine component. In this paper, the overlay welding method on the Nimonic super alloy was established by the PTA overlay welding process using the same super alloy powder. The characteristics of the Co-base and Ni-base super alloy overlay layers were investigated through the metallurgical, abrasive and cavitation erosion test. The abrasive and cavitation characteristics were investigated at room and high temperature.

유용 자원식물의 진균성 신병해(I) (New Fungal diseases of Economic Resource Plants in Korea(I))

  • 신현동
    • 한국식물병리학회지
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    • 제10권3호
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    • pp.181-191
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    • 1994
  • Occurrence of diseases in economic resource plants in Korea is poorly known. This paper reports short descriptions on symptom, occurrence condition, pathogen, and some phytopathological notes for each 10 fungal plant diseases new to Korea; leaf spot of Rosa multiflora with Seimatosporium discosioides causing leaf spot and defoliation, leaf blight of Equisetum arvense with Titaeospora equiseti causing leaf spot to leaf blight, leaf blight of Setaria viridis with Phyrenochaeta setariae causing leaf spot of Aster tataricus with Septoria astericola causing leaf spot and black spot, powdery mildew of Clematis fusca var. coreana with Erysiphe ranunculi causing powdery mildew and dwarfing, powder mildew of Ligularia stenocephala with Erysiphe galeopsidis causing powdery mildew and dwarfing, powdery mildew of Phlox subulata with Erysiphe cichoracearum causing powdery mildew and defoliation tar spot of Lonicera japonica with Rhytisma lonicericola causing tar spot and dwarfing, white rust of Pharbitis nil with Albugo ipomoeae-pandulatae causing white rust and deformation, and white rust of Achyranthes japonica with Albugo achyranthis causing white rust and defoliation.

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MR 엘라스토머의 감쇠 및 강성 특성에 대한 실험조사 (Experimental Study on the Damping and Stiffness Characteristics of MR Elastomers)

  • 곽문규;정문산;배병찬;허석;송명호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 춘계학술대회논문집
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    • pp.1137-1141
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    • 2007
  • This paper is concerned with the experimental research of magnetorheological elastomers (MREs). The modulus of the MR elastomers can be controlled by an applied magnet field, so that it can be effectively used for vibration suppression applications. The MR elastomer in this experiment is a mixture of KE-1300 silicone, carbonyl iron powder (300mesh) and a silicone hardener (CAT-1300). Three specimens were manufactured and tested by using the vibration testing instruments. The magnetic field was generated by the permanent magnets. The experimental results show that the natural frequencies of the test article with MR elastomer changes by the applied magnetic field. The performance of the MR elastomer can be increased by stronger magnetic fields. This is under investigation.

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Pilot-Scale Production of Cellulase Using Trichoderma reesei Rut C-30 Fed-Batch Mode

  • Lee, Sang-Mok;Koo, Yoon-Mo
    • Journal of Microbiology and Biotechnology
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    • 제11권2호
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    • pp.229-233
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    • 2001
  • Trichoderma reesei Rut C-30 produced high levels of ${\beta}$-glucosidase, endo-${\beta}$-glucosidase, endo-${\beta}$-1,4-glucanase, and exo-${\beta}$-1,4-glucanase. In pilot-scale production (50-1 fermentor), productivity and yield of CMCase (carborymethyl cellulose) and FPase (filter paper activity) were 273 U/ml and 35 U/ml, and 162 FPU/l.h and 437 FPU/g, respectively. The fed-batch techniques were used to improve enzyme activities with constant cell concentration. The acidity was an important parameter and controlled at pH 3.9 and 5.0 by automatic addition of ammonium hydroxide. Cellulase powder was prepared by ammonium sulfate precipitation and its CMCase and FPase activities were 3,631 U/g and 407 U/g, respectively.

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1,4-Diketo-3,6-Diphenyl-Pyrrolo-[3,4c]-Pyrrole(DPP)계 유기안료의 합성 및 흡수스펙트라 (Synthesis and Absorption Spectra of 1,4-Diketo-3,6-Diphenyl-Pyrrolo-[3,4c]-Pyrrole)

  • 김성훈
    • 한국인쇄학회지
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    • 제14권1호
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    • pp.1-15
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    • 1996
  • In this paper, the preparation of lead zirconium titanate(PZT) thin film by sol-gel processing was descried. Thin film coated with thickness of 4${\mu}{\textrm}{m}$ on the stainless steel substrates using the multiple spin-coating process. The crystalline phases of PZT powder and film were investigated by X-ray diffraction pattern and PZT thin film has perovskite structure over 600 C annealing temperature. Corona charging characteristics of the ferroelectric PZT thin film at 600 C were investigated by electrophotographic measurement. A difference in the charging characteristics between positive and negative corona charging was found. The charge acceptance depended in the polarity of corona and the poling of film. According to the D-E hysteresis measurment, PZT thin film can be poled by corona charging without use of top electrode. The remnant polarization in the PZT thin film is generally in the order of 48$\mu$C/$\textrm{cm}^2$. From this results, the ferroelectric PZT thin film will be possible to apply for the add-on type imaging formation.

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Cellulase Production in Fed-Batch Culture by Trichoderma reesei Rut C30

  • Yu, Xiao-Bin;Yun, Hyun-Shik;Koo, Yoon-Mo
    • Journal of Microbiology and Biotechnology
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    • 제9권1호
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    • pp.44-49
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    • 1999
  • Cellulase production by fed-batch cultivation of Trichoderma reesei Rut C30 with various initial concentrations of Solka Floc in 1 % wheat bran-containing medium was investigated. The cellulase activity and productivity increased with initial Solka Floc concentration up to 5%. When a total Solka Floc concentration of 90 g/l was used for cellulase production, CMC (carboxymethyl cellulose) and FP (filter paper) activities, productivity, and yield were 359.7 U/ml, 30.61 U/ml, 161 FPU $L^{-1}$ $h^{-1}$, and 340 FPU $g^{-1}$, respectively. It was important to maintain a high cell concentration during cellulase production to obtain high cellulase activity and productivity. Cellulase powder was prepared by ammonium sulfate precipitation: FP activity was 396.7 U/g and CMC activity was 6481 U/g.

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메이크업 화장품용 분체에 관한 연구 (A Study on the Powders for Makeup Cosmetics)

  • 고종성;이진휘;성기천
    • 한국응용과학기술학회지
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    • 제29권2호
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    • pp.286-294
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    • 2012
  • 본 연구는 메이크업 화장품용 분체에 관한 리뷰논문이다. 분체는 피부 결함 은폐, 자외선 차단, 화장 지속성, 피부보호의 역할을 주요목적으로 한다. 이러한 기능은 분체의 형태제어, 표면처리, 캡슐화로 부여된다. 미래의 분체는 환경변화에 응답하는 스마트 형태로 진화할 것으로 보인다.