• 제목/요약/키워드: sequential properties

검색결과 274건 처리시간 0.026초

Development and Verification of an Optimum Composition Model for a Synbiotic Fermented Milk Using Sequential Quadratic Programming Techniques

  • Chen, Ming-Ju;Chen, Kun-Nan;Lin, Chin-Wen
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제19권10호
    • /
    • pp.1490-1495
    • /
    • 2006
  • The purpose of this research was to develop an optimum composition model for a new synbiotic fermented dairy product with high probiotic cell counts, and to experimentally verify this model. The optimum composition model indicated the growth promoter ratio that could provide the highest growth rate for probiotics in this fermented product. Different levels of growth promoters were first blended with milk to improve the growth rates of probiotics, and the optimum composition model was determined. The probiotic viabilities and chemical properties were analyzed for the samples made using the optimal formula. The optimal combination of the growth promoters for the synbiotic fermented milk product was 1.12% peptides, 3% fructooligosaccharides (FOS), and 1.87% isomaltooligosaccharides (IMO). A product manufactured according to the formula of the optimum model was analyzed, showing that the model was effective in improving the viability of both Lactobacillus spp. and Bifidobacterium spp.

압전-구조-음향 연성계의 압전 액츄에이터 최적설계 (Shape Optimization of Piezoelectric Materials for Piezoelectric-Structure-Acoustic System)

  • 왕세명;이강훈
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2000년도 춘계학술대회논문집
    • /
    • pp.1627-1632
    • /
    • 2000
  • Recently, piezoelectric materials have attracted considerable attention because of its self-sensing and actuating properties. To model smart structures, numerical modeling of structures with piezoelectric devices is essential. As many factors affect the performance of smart structures, optimization of these parameters is necessary. In this paper, the shape design sensitivity analysis of the 3D piezoelectric and structural elements is developed and shape optimization is performed. For the evaluation of the sensitivity, the finite element method is used. For the shape sensitivity, the domain velocity field is calculated. An acoustic cavity model is presented as a numerical example to study the feasibility of the formulation. The continuum sensitivity is compared with the results of the finite difference method by ANSYS. And the sequential linear programming (SLP) algorithm is used as the optimization algorithm.

  • PDF

The Detection and Testing of Multiple Outliers in Linear Regression

  • Park, Jin-Pyo;Zamar, Ruben H.
    • Journal of the Korean Data and Information Science Society
    • /
    • 제15권4호
    • /
    • pp.921-934
    • /
    • 2004
  • We consider the problem of identifying and testing outliers in linear regression. First, we consider the scale-ratio tests for testing the null hypothesis of no outliers. A test based on the ratio of two residual scale estimates is proposed. We show the asymptotic distribution of test statistics and investigate the properties of the test. Next we consider the problem of identifying the outliers. A forward procedure based on the suggested test is proposed and shown to perform fairly well. The forward procedure is unaffected by masking and swamping effects because the test statistics used a robust scale estimate.

  • PDF

Fabrication of Organic-Inorganic Hybrid Thin Film by Molecular Layer Deposition

  • 한규석;김수환;한기복;성명모
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
    • /
    • pp.251-251
    • /
    • 2010
  • Organic-inorganic hybrid materials have attracted because of its combined properties, such as flexibility and high electrical performance. In addition, the hybrid materials are expected to have synergic effect which are not shown in just one component. Here, we fabricated organic-inorganic hybrid thin film. Organic-inorganic hybrid thin film have been deposited from diethyl zinc and 1, 2, 4-trihydroxybenzene (THB) by molecular layer deposition (MLD). UV-VIS, Using Infrared spectrum and X-ray photoelectron spectroscopy confirm that Zinc and THB hybrid film (ZnTHB) consist of Zn-O and THB - oxide units and the micro structure and composition of hybrid film. hat the sequential surface reactions of diethyl zinc and ethylene glycol are sufficiently self-limiting and saturating to enable well-controlled MLD growth. Transmission electron microscopy image shows lamination growth of ZnTHB film according to cycle.

  • PDF

Poly(Styrene/Acrylate) Core-Shell 라텍스 입자의 제조와 물성에 관한 연구 (Preparation and Physical Properties of Poly(Styrene/Acrylate) Core-Shell Latex Particles)

  • 이경구;박근호
    • 한국응용과학기술학회지
    • /
    • 제20권1호
    • /
    • pp.27-32
    • /
    • 2003
  • The core-shell latex particles were prepared by sequential emulsion polymerization of alkyl methacrylate and styrene(ST) by using an water-soluble initiator(APS) after preparing monomer pre-emulsion in the presence of an anionic surfactant(SDBS). In organic/organic core-shell polymerization, the pre-emulsion method, which minimized required quantity of sulfactant, has been used to increase the conversion rate and the stability of core-shell latex particles as well as to reduce the formation of secondary particle that cause problems of soap-free emulsion during shell polymerization. We used several methods to observe the core-shell structure. The core-shell structure was studied by measuring pH change during hydrolysis by NaOH, glass transition temperature($T_g$) by differential scanning calorimeter(DSC), morphology of latex by transmission electron microscope(TEM) and change of particle size and distribution by a particle analyzer.

Number of Graphene Layers As a Modulator of the Open-circuit Voltage of Graphene-Based Solar Cell

  • 임규욱;이경재;임종태;강태희;정석민;홍병희;염근영
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
    • /
    • pp.113-113
    • /
    • 2011
  • Impressive optical properties of graphene have been attracting the interest of researchers, and, recently, the photovoltaic effects of a heterojunction structure embedded with few layer graphene (FLG) have been demonstrated. Here, we show the direct dependence of open-circuit voltage (Voc) on numbers of graphene layers. After unavoidably adsorbed contaminants were removed from the FLGs, by means of in situ annealing, prepared by layer-by-layer transfer of the chemically grown graphene layer, the work functions of FLGs showed a sequential increase as the graphene layers increase, despite of random interlayer-stacking, resulting in the modulation of photovoltaic behaviors of FLGs/Si interfaces.

  • PDF

Catalyst-Free and Large-Area Deposition of Graphitic Carbon Films on Glass Substrates by Pyrolysis of Camphor

  • Nam, Hyobin;Lee, Woong
    • 한국재료학회지
    • /
    • 제25권7호
    • /
    • pp.341-346
    • /
    • 2015
  • The feasibility of obtaining graphitic carbon films on targeted substrates without a catalyst and transfer step was explored through the pyrolysis of the botanical derivative camphor. In a horizontal quartz tube, camphor was subjected to a sequential process of evaporation and thermal decomposition; then, the decomposed product was deposited on a glass substrate. Analysis of the Raman spectra suggest that the deposited film is related to unintentionally doped graphitic carbon containing some $sp-sp^2$ linear carbon chains. The films were transparent in the visible range and electrically conductive, with a sheet resistance comparable to that of graphene. It was also demonstrated that graphitic films with similar properties can be reproduciblyobtained, while property control was readily achieved by varying the process temperature.

Magnetic Characterization of the Nd Based Permanent Magnet by Newly-Developed Bipolar Pulse-Type Hysteresis Loop Tracer

  • Rhee, J.R.
    • Journal of Magnetics
    • /
    • 제4권3호
    • /
    • pp.73-75
    • /
    • 1999
  • By appliying an slternate pulsed magnetic field -generated by using a sequential ignition circuit and a magnet exciting circuit- with peak value of about 10 T to the rod type Nd based magnet Nd2Fe12.7Cr1.3B with length of 5 mm and diameter of 3.6 mm, the basic magnetic properties such as saturation magnetization, residual magnetization, coercivity, maximum energy products, magnetic anisotropy and anisotropic field are investigated with obtaining the major and minor J-H loops of the magnet. The increase in coercivity due to eddy currents in ac measurement of coercivity is calculated considering eddy current loss by analyzing a wave of generating magnetic field. The average coercivity calculated for the magnet is about 12.2 kOe, anisotropy magnetic field and anisotropic constant are measured as 60 kOe 2.43 Mj/$m^3$, respectively.

  • PDF

구조물의 자유진동특성 추정을 위한 실험적 연구 (Experimental Study on Modal Parameter Estimation of Structures)

  • 윤정방;이형진
    • 전산구조공학
    • /
    • 제7권4호
    • /
    • pp.137-144
    • /
    • 1994
  • 기존 대형구조물의 안전진단에 관련하여 구조계의 동적계수를 실험적으로 추정하는 방법이 연구되었다. 시간영역방법인 순차적 예측오차방법과 주파수영역의 방법인 주파수응답함수 추정법이 비교검토되었다. 기법의 검증은 2 Bay 3층 구조물 모형에 대해서 수행되었는데, 각 실험적 방법에 의한 추정결과는 일관된 추정치를 보이었다. 그러나, 유한요소법에 의한 결과와는 차이를 보이었다. 이 차이는 구조해석시 절점조건에 대한 부적절한 모형화에 기인한 것으로 사료된다.

  • PDF

두 단계 열처리에 의해 제작된 다결정 실리콘 박막트랜지스터의 전기적 특성의 분석 (Analysis of electrical properties of two-step annealed polycrystalline silicon thin film transistors)

  • 최권영;한민구;김용상
    • 대한전기학회논문지
    • /
    • 제45권4호
    • /
    • pp.568-573
    • /
    • 1996
  • The amorphous silicon films deposited by low pressure chemical vapor deposition are crystallized by the various annealing techniques including low-temperature furnace annealing and two-step annealing. Two-step annealing is the combination of furnace annealing at 600 [.deg. C] for 24 h and the sequential furnace annealing at 950 [.deg. C] 1h or the excimer laser annealing. It s found that two-step annealings reduce the in-grain defects significantly without changing the grain boundary structure. The performance of the poly-Si thin film transistors (TFTs) produced by employing the tow-step annealing has been improved significantly compared with those of one-step annealing. (author). 13 refs., 6 figs., 1 tab.

  • PDF