• Title/Summary/Keyword: spectral peak

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Synthetic Strategy and Optical Property Characterization of Complex Nanorods: Plasmon Wave Guide and Solar Cell

  • Park, Sung-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.111-111
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    • 2012
  • In this talk, we represent a novel approach to investigating intra-nanorod surface plasmon coupling with control over block compositions. The multi-component rod-like nanostructures, which consist of optically active components (Au and Ag) and optically less active component (for example, Ni) in UV-vis-NIR spectral window, showed interesting optical response depending on each block length and the total length of the structure. By controlling the composition and relative lengths of the blocks that comprise these structures, we can tailor the overall optical properties. Depending on the relative fraction of Au and Ag blocks, the intensity of the transverse modes varied without noticeable peak shifts. However, the strong intraparticle surface plasmon coupling resulted in the collective appearance of longitudinal LSP modes, including higher-order modes. The experimental observations were confirmed by theoretical calculation, using a discrete dipole approximation method. In addition, we will briefly discuss how single nanorod solar cells can be synthesized by using by using electrochemical deposition and AAO hard templates.

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A Study On Arbitrary Artificial Earthquake Acceleration Generation -Based On Design Response Spectrum of Arbitrary Damping Value- (임의의 인공지진 가속도 발생에 관한 연구 -설계응답 스펙트럼에 기초하여 -)

  • 우운택;김영문;노재선
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1989.04a
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    • pp.5-10
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    • 1989
  • In this study, the basic concept of design response spectrum is briefly revi-ewed. To generate the artificial earthquake acceleration, the method of superpo-sition of cosine waves is used. Theoretical developments using F.F.T. and spect-ral density function are compared. The amplitude was derived by use of the peak factor and the phase angle is d-erived by use of Monte Carlo simulation. To smoothen the match, the calculated pseudo velocity respon-se spectrum is compared with input pseudo velocity response spectrum at a set of control frequencies. With the modified spectral density function, a new acceleration and pseudo velocity response spectrum are generat-ed.

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A Comparison of Front-Ends for Robust Speech Recognition

  • Kim, Doh-Suk;Jeong, Jae-Hoon;Lee, Soo-Young;Kil, Rhee M.
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.3E
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    • pp.3-11
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    • 1998
  • Zero-crossings with Peak amplitudes (ZCPA) model motivated by human auditory periphery was proposed to extract reliable features form speech signals even in noisy environments for robust speech recognition. In this paper, the performance of the ZCPA model is further improved by incorporating conventional speech processing techniques into the model output. Spectral and cepstral representations of the ZCPA model output are compared, and the incorporation of dynamic features with several different lengths of time-derivative window are evaluated. Also, comparative evaluations with other front-ends in real-world noisy environments are performed, and result in the superiority of the ZCPA model.

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A Continuous Wavelet Study on Approach Wind and Building Pressure (접근풍속과 건물 변동풍압력에 대한 연속파동변화법의 적용)

  • Ham, Hee-Jung
    • Journal of Industrial Technology
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    • v.25 no.B
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    • pp.89-97
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    • 2005
  • Application of proper orthogonal decomposition (POD) and continuous wavelet transform (CWT) is introduced to study wind speed and building roof pressures of flow separation region. In this study, a detailed analysis of the approach wind flow, wind-induced building pressure and the relation between the two fields was carried out using the POD technique and CWT analysis. The results show potential of the application of POD and CWT in characterization of spatio-temporal and spectral properties of the approach wind and its induced dynamic pressure events. Some of findings resulting from the application of this analysis can be summarized as follows: (1) The POD first principal coordinate of the roof pressure in the separated shear layer is closely correlated with the longitudinal component of oncoming flow. (2) The CWT analysis suggests that the extreme peak pressure in the separated shear layer is due to condensed large-scale eddy motions.

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Artifical Neural Network for In-Vitro Thrombosis Detection of Mechanical Valve

  • Lee, Hyuk-Soo;Lee, Sang-Hoon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.06a
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    • pp.762-766
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    • 1998
  • Mechanical valve is one of the most widely used implantable artificial organs, Since its failure (mechanical failures and thrombosis to name two representative example) means the death of patient, its reliability is very important and early noninvasive detection is essential requirement . This paper will explain the method to detect the thrombosis formation by spectral analysis and neural network. In order quantitatively to distinguish peak of a normal valve from that of a thrombotic valve, a 3 layer backpropagation neural network, which contains 7,000 input nodes, 20 hidden layer and 1output , was employed. The trained neural network can distinguish normal and thrombotic valve with a probability that is higher than 90% . In conclusion, the acoustical spectrum analysis coupled with a neural network algorithm lent itself to the noninvasive monitoring of implanted mechanical valves. This method will be applied to be applied to the performance evaluation of other implantable rtificial organs.

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Thermal denaturation analysis of protein

  • Miyazawa, Mitsuhiro
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1628-1628
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    • 2001
  • Near infrared (NIR) spectroscopy is a powerful technique for non-destructive analysis that can be obtained in a wide range of environments. Recently, NIR measurements have been utilized as probe for quantitative analysis in agricultural, industrial, and medical sciences. In addition, it is also possible to make practical application on NIR for molecular structural analysis. In this work, Fourier transform near infrared (FT-NIR) measurements were carried out to utilize extensively in the relative amounts of different secondary structures were employed, such as Iysozyme, concanavalin A, silk fibroin and so on. Several broad NIR bands due to the protein absorption were observed between 4000 and $5000\;^{-1}$. In order to obtain more structural information from these featureless bands, second derivative and Fourier-self-deconvolution procedures were performed. Significant band separation was observed near the feature at $4610\;^{-1}$ ,. Particularly the peak intensity at $4525\;^{-1}$ shows a characteristic change with thermal denaturation of fibroin. The structural information can be also obtained by mid-IR and CD spectral. Correlation of NIR spectra with protein structure is discussed.

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Initial-phase Sensitivity Analysis of Harmonic Measurements via Windowed DFT

  • Song, Shuping;Wang, Fuzong;Cheng, Guozhu
    • Transactions on Electrical and Electronic Materials
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    • v.15 no.4
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    • pp.182-188
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    • 2014
  • When the windowed DFT algorithm is applied in harmonic measurements, the problem of initial-phase sensitivity will be encountered, this has an effect on harmonic amplitude accuracy. In this paper, the origin of initial-phase sensitivity is analyzed and the main factors that influence the level of initial-phase sensitivity are demonstrated. A method of reducing initial-phase sensitivity is proposed to increase the stability of harmonic measurements. We found that initial-phase sensitivity is determined by the side lobe peak level of the window functions when synchronous deviation is fixed. In addition, increasing the length of the time recorded can be used to remove initial-phase sensitivity. The correctness and validity of our conclusions have been confirmed through numerical results and field tests.

A stability on the solvents of 9-Phenyl-5,5'-Diphenyl-3,3'-Bis-(3-sulfopropy)-benzoxazolo carbocyanine triethyl ammonium salt (9-Phenyl-5,5'-Diphenyl-3,3'-Bis-(3-sulfopropy)-Benzoxazolo Carbocyanine Triethyl Ammonium Salt의 용매에 대한 안정성)

  • Kim, Yeoung-Chan
    • The Journal of Information Technology
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    • v.7 no.2
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    • pp.1-5
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    • 2004
  • The symmetric 9-phenyl-5,5'-diphenyl-3,3'-bis-(3-sulfopropyl)-benzoxazolo carbocyanine triethyl ammonium salt is of industrial importance as green-sensitizing dye in the spectral sensitization of emulsion microcrystals in negative film and positive paper-making. The stability on the solvents of benzoxazolo carbocyanine dye was measured by UV-Vis spectrophotometer, and then dye was stabilized in various solvents. The maximum absorption peak range in various solvents was 507nm~515nm. It was identified that the solvents can be used to photographic emulsion.

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Stochastic response spectra for an actively-controlled structure

  • Mochio, Takashi
    • Structural Engineering and Mechanics
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    • v.32 no.1
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    • pp.179-191
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    • 2009
  • A stochastic response spectrum method is proposed for simple evaluation of the structural response of an actively controlled aseismic structure. The response spectrum is constructed assuming a linear structure with an active mass damper (AMD) system, and an earthquake wave model given by the product of a non-stationary envelope function and a stationary Gaussian random process with Kanai-Tajimi power spectral density. The control design is executed using a linear quadratic Gaussian control strategy for an enlarged state space system, and the response amplification factor is given by the combination of the obtained statistical response values and extreme value theory. The response spectrum thus produced can be used for simple dynamical analyses. The response factors obtained by this method for a multi-degree-of-freedom structure are shown to be comparable with those determined by numerical simulations, demonstrating the validity and utility of the proposed technique as a simple design tool. This method is expected to be useful for engineers in the initial design stage for structures with active aseismic control.

Scientific Studies on Ancient Silk Fibers Used for Textiles Excavated at Archaeological Sites in Japan, Using Microscopic Fourier Transform Infrared Spectroscopy

  • SATO, Masanori
    • Journal of Conservation Science
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    • v.5 no.2 s.6
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    • pp.45-50
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    • 1996
  • Silk fibers excavated at Fujinoki mounted tomb, Shimoikeyana mounted tomb and Kuriyama site were examined using FT-IR microscope and two peaks called amide I and II present in modern silk fibers were compared with those of excavated fibers. It was found that amide ground in a polymer molecule decreased with the progress of degradation and peak intensity of amide group in infrared spectrum decreased correspondingly. The advantages of FT-IR microscopy for the analysis of organic remains in archaeological view point were evaluated and it was concluded that the systematic investigation of spectral change due to the degradation of respective material is essential.

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