• Title/Summary/Keyword: Structure Enhancement

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Simultaneous Spectral Resolution and Sensitivity Enhancement in MR spectrum: Maximum Likelihood Deconvolution Reconstruction

  • Jeong, Gwang-Woo;Jeong, Jenny Eunice;Kang, Heoung-Keun
    • Journal of the Korean Magnetic Resonance Society
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    • v.15 no.2
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    • pp.157-174
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    • 2011
  • Although the use of apodization functions in connection with postprocessing of a 2D NMR spectrum proves improved spectral quality, there is usually a trade-off between resolution enhancement and noise suppression due to a classical "uncertainty principle." In this study, therefore, a mathematical deconvolution technique called "Maximum Likelihood Deconvolution (MLD)" was adopted to achieve the spectral resolution and sensitivity enhancement simultaneously. The MLD technique greatly facilitates visualization and restoration of the genuine spectral information from complex 2D NMR spectra that would be problematic with the conventional apodization/FT processing. In particular, application of the MLD to the 2D-NOE spectrum would be very useful to derive the important proton connectivities, which are essential to achieve elucidating the 3D molecular structure.

A study on the Image Edge Enhancement Detection of the Hybrid FCNN using the Morphological Operations (형태학 연산자를 이용한 하이브리드 FCNN의 영상 에지 고양 검출에 관한 연구)

  • 홍연희;변오성;조수형;문성룡
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.1025-1028
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    • 1999
  • After detecting the edge which is applying the morphological operators to the hybrid FCNN, we could analyze and compare. The hybrid FCNN is completely removed to the noise in the image, and worked in order to obtain the result image which is closest to the original image. Also, the morphological operator is applied to the image as the method in order to detect more good the edge than the conventional edge. FCNN which is the pipeline type is completely suitable to detecting the image processing as well as the hardware size. In this paper. we would make the structure elements of the morphological operator the variable template and the static template, and compare with the edge enhancement of two images. After being the result which is applying the variable template morphological operator and the static template morphological operator to the image, we could know that the edge images applying the variable template is superior in a edge enhancement side.

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Researches on the Enhancement of Plasticity of Bulk Metallic Glass Alloys

  • Kim, Byoung Jin;Kim, Won Tae
    • Applied Microscopy
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    • v.45 no.2
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    • pp.52-57
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    • 2015
  • Bulk metallic glass (BMG) shows higth strength, high elastic limit, corrosion resistance and good wear resistance and soft magnetic properties and has been considering as a candidate for new structural materials. But they show limited macroscopic plasticity and lack of tensile ductility due to highly localized shear deformation, which should be solved for real structural application. In this paper researches on the enhancement of plasticity of BMG were reviewed briefly. Introducing heterogeneous structure in glass is effective to induce more shear transformation zones (STZs) active for multiple shear band initiation and also to block the propagating shear band. Several methods such as BMG alloy design for high Poisson's ratio, addition of alloying element having positive heat of mixing, pre-straining BMG and variety of BMG composites have been developed for homogenous distribution of locally weak region, where local strain can be initiated. Therefore enhancement of plasticity of BMG is normally accompanied with some penalty of strength loss.

Securitization and Monitoring Incentives (자산유동화와 모니터링 유인간의 관계)

  • Han, Jae-Joon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.37 no.2
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    • pp.17-29
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    • 2012
  • We examine a mortgage bank's incentive distortion problem when the bank sells its existing loan through MBS(Mortgage-Backed Security), considering the mortgage market structure and varying investors' risk attitude. Main findings in our comparative statics are the followings. The bank's monitoring incentive on the loan sold is distorted downwards when the deposit interest rate is lower than the coupon rate of MBS. Credit enhancement associated with the loan sale may mitigate the incentive distortion problem. However, the downward distortion of monitoring incentive does not disappear unless the credit enhancement, a loan guarantee, is provided up to 100%. Finally as the investors' risk preference changes from risk-neutral to risk-averse type, the incentive distortion problem becomes more severe. At the end, we recommend the introduction of covered bond in order to mitigate the incentive distortion problem, which is inevitable to current pass-through MBS.

CNTs Electric Field Enhancement of CIGS Solar Cells

  • Han, Seong-Hwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.67-67
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    • 2011
  • Compound semiconductor/CNTs composites have shown considerably improved efficiency improvement in photovoltaic devices, which is often attributed to two different factors. One is the formation of efficient electronic energy cascade structures. The other effect of CNTs on the performance of photovoltaic devices is the decrement of interfacial resistance. The interfacial resistances at n-type/ p-type materials and/or n-type materials/TCO electrode are reduced by an outstanding electrical property of CNTs. In addition to the effects of CNTs, we report the third reason for increment of efficiency in photovoltaic devices by CNT's well-known electrical field enhancement effects. The improved ${\beta}$ values in reverse-FE currents of CIGS electrode with SWNTs layers indicate the enhancement of electrical field in photovoltaic devices, which implies the acceleration of the electron transfer rate in the cell. Due to the formation of an efficient electronic energy cascade structure and the decrease of the interfacial resistance as well as the improvement of the electrical field in the photovoltaic devices, the power conversion efficiency of electrochemically deposited superstrate-type CIGS solar cells was increased 24.3% in the presence of SWNTs and showed 10.40% conversion efficiency.

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A Study on the Design of Integrated Speech Enhancement System for Hands-Free Mobile Radiotelephony in a Car

  • Park, Kyu-Sik;Oh, Sang-Hun
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.2E
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    • pp.45-52
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    • 1999
  • This paper presents the integrated speech enhancement system for hands-free mobile communication. The proposed integrated system incorporates both acoustic echo cancellation and engine noise reduction device to provide signal enhancement of desired speech signal from the echoed plus noisy environments. To implement the system, a delayless subband adaptive structure is used for acoustic echo cancellation operation. The NLMS based adaptive noise canceller then applied to the residual echo removed noisy signal to achieve the selective engine noise attenuation in dominant frequency component. Two sets of computer simulations are conducted to demonstrate the effectiveness of the system; one for the fixed acoustical environment condition, the other for the robustness of the system in which, more realistic situation, the acoustic transmission environment change. Simulation results confirm the system performance of 20-25dB ERLE in acoustic echo cancellation and 9-19 dB engine noise attenuation in dominant frequency component for both cases.

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Sensitivity Enhancement of Surface Plasmon Resonance Biosensor with Colloidal Gold

  • Kibong Choi;Hee
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.3 no.1
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    • pp.19-23
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    • 1998
  • We enhanced the sensitivity of surface plasmon resonance biosensor by the conversion of the real-time direct binding immunoassay into the sandwich immunoassay, in which colloidal gold particles coated with anti-mouse IgG was used. By the immobilization of anti-mouse IgG onto the carboxymethyl dextran surface of thin gold film, the direct binding of analyte(mouse IgG) onto the sensor chip, and the injection of colloidal gold particles coated with anti-mouse IgG, about 100 times of sensitivity enhancement was obtained. This result suggests that nanoparticles, which has a high refractive index, homogeneous ultrafine structure and capability of size control, would be applicable for the detection of very small quantity of biomaterial.

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Optimization of multiple-quantum-well structures in 1.55.$\mu$ InGaAsP/InGaAsP SL-MQW DFB-LD for high-speed direct modulation (고속직접변조를 위한 1.55.$\mu$. InGaAsP/InGaAsP SL-MQW DFB-LD의 양자우물구조의 최적화)

  • 심종인;한백형
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.3
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    • pp.60-73
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    • 1997
  • By introducing a compressive-strained quanternary InGaAsP quantum-wells instead of a conventional ternary InGaAs quantum-wells in 1.55.mu.m DFB-LD, the lasing performances canb e improved and the problems caused by the thickness non-uniformity and the compositional abruptness among the hetero-interpaces canb e relaxed. In this paper, we investigated an iptimum InGaAsP/InGaAsP multiple-quantum-well(MQW) structure as an active layer in a direct-modulated 1.55.mu. DFB-LD from the view point of threshold current, chirping charcteristics, and resonance frequency. The optimum compressive-strained MQW structure was revealed as InGaAsP/InGaAsP structure with strain amount of about 1.2%, number of wells $N_{w}$ of 7, well width $L_{w}$ of 58.agns.. The threshold current density J of 500A/c $m^{2}$, the linewidth enhancement factor a of 1.8, and differential resonance frequency of d $f_{r}$/d(I-I)$^{1}$2/=2GHz/(mA)$^{1}$2/(atI=2 $I_{th}$) were expected in 1.55.mu.m .gamma./4-shifted DFB-LD with the cavity length of 400.mu.m long and kL value of 1.25. These values are considerably improved ones compared to those of 1.55um DFB-LD with InGaAs/InGaAsP MQW which have enhancement factor and the resonance frequence frequency by the detuning of lasing wavelength and gain-peak wavelength. It was found that the linewidth enhancement factor of 20% and differential resonance frequency of 35% without the degradation of the threshold current density could be enhanced in the range of -15nm~-20nm detuning which can be realized by controlling the thickness and Incomposition of InGaAsP well. well.and Incomposition of InGaAsP well. well.

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A Confirmatory Factor Analysis on the Performance Enhancement Attitude Scale-Korean version for Elite Athletes (확인적 요인분석을 통한 엘리트 선수들의 한국형 운동수행능력 향상에 대한 태도 척도에 관한 연구)

  • Park, Jaemyoung;Kim, Taegyu
    • Journal of Digital Convergence
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    • v.16 no.11
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    • pp.599-604
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    • 2018
  • This study aimed to examine the various factors structure of Performance Enhancement Attitude Scale (PEAS) by using confirmatory factor analysis and to provide a suitable questionnaire for elite athletes to measure attitudes toward doping. Three hundred and fifty-five handball players participated in this study and they filled out a self-administrated 17-items PEAS. And 17-items, 11-items, 9-items, 8-items and 6-items PEAS were examined by using confirmatory factor analysis, respectively. 6-items PEAS was suitable to measure attitudes toward doping for adult athletes, and PEAS for adolscent should be developed by being consisted of suitable questions for adolscent athletes.

Fundamental Study on Heat Transfer Enhancement Effect of Microscale Surface Wrinkles (마이크로 표면주름 형상에 따른 열전달 촉진효과 기초연구)

  • Park, Hee-Jin;Park, Sang-Hu
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.9
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    • pp.447-452
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    • 2014
  • We evaluated heat transfer characteristics of microscale wrinkles using a CFD (computational fluid dynamics) analysis. In order to verify the heat transfer effect of wrinkles having various shapes, we introduce wrinkling processes to generate few different shapes of wrinkles such as macroscale ($200{\sim}400{\mu}m$ width), microscale ($10{\sim}30{\mu}m$ width), and hierarchical (microscale on macroscale wrinkle) wrinkles, using repetitive-dividing-volume (RDV) method for single-shape of wrinkles and connected method of UV-weakly polymerization with thermal curing for hierarchical structure of winkles. The analysis results of simplified CFD model showed that heat flux on heated plate was changed by the shape of wrinkles on the plate. The increase in heat flux of about 2.6 times was achieved in the case where hierarchical wrinkle structure was used.