• Title/Summary/Keyword: multi-resonance

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Remodeling of Infarcted Myocardium with Contrast-Enhanced Magnetic Resonance Imaging

  • 최병욱;최규옥;김영진;정남식;임세중
    • Proceedings of the KSMRM Conference
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    • 2003.10a
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    • pp.92-92
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    • 2003
  • To evaluate remodeling of infarcted myocardium with contrast-enhanced MRI (co-MRI) at true end-diastole (ED) MRI was performed with a Gyroscan Intera (1.5 Tesla, Philips, Netherlands) in 13 patients with acute subendocardial myocardial infarction. The First exam was done 0-15 days (mean 5.2days) after symptom onset and the second exam 28-88days (mean 49 days) after the first exam. Ce-MRI encompassing the entire left ventricle was peformed with a multi-shot, turbo-field-echo, breath-hold sequence and a non-selective, inversion prepulse 10 minutes after the intravenous injection of Gd-DTPA at a dose of 0.2 mmol/kg body weight. To allow the long TD, ECG synchronization should use two RR-intervals for one acquisition of a segment of k-space by setting the heart rate to half that of the true heart rate. Trigger delay time (TD) was adjusted to the RR-interval for true end-diastolic imaging. The other typical parameters were TR=5.4ms, TE=1.6ms, voxel size=1.37$\times$1.37$\times$10mm, k-space data segmented into 8 segments with 32 lines of segment per two cycles over 16 cardiac cycles. The thickness of hyperenhanced myocardium and epicardially nonenhanced myocardium were followed.

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Fast Cardiac CINE MRI by Iterative Truncation of Small Transformed Coefficients

  • Park, Jinho;Hong, Hye-Jin;Yang, Young-Joong;Ahn, Chang-Beom
    • Investigative Magnetic Resonance Imaging
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    • v.19 no.1
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    • pp.19-30
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    • 2015
  • Purpose: A new compressed sensing technique by iterative truncation of small transformed coefficients (ITSC) is proposed for fast cardiac CINE MRI. Materials and Methods: The proposed reconstruction is composed of two processes: truncation of the small transformed coefficients in the r-f domain, and restoration of the measured data in the k-t domain. The two processes are sequentially applied iteratively until the reconstructed images converge, with the assumption that the cardiac CINE images are inherently sparse in the r-f domain. A novel sampling strategy to reduce the normalized mean square error of the reconstructed images is proposed. Results: The technique shows the least normalized mean square error among the four methods under comparison (zero filling, view sharing, k-t FOCUSS, and ITSC). Application of ITSC for multi-slice cardiac CINE imaging was tested with the number of slices of 2 to 8 in a single breath-hold, to demonstrate the clinical usefulness of the technique. Conclusion: Reconstructed images with the compression factors of 3-4 appear very close to the images without compression. Furthermore the proposed algorithm is computationally efficient and is stable without using matrix inversion during the reconstruction.

The Power Supply for High Frequency Induction Heating by using the Current Resonance (전류공진을 이용한 고주파 유도가열용 전원장치)

  • Ra, B.H.;Lee, E.Y.;Song, D.H.;Suh, K.Y.;Lee, H.W.
    • Proceedings of the KIEE Conference
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    • 2002.11d
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    • pp.263-266
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    • 2002
  • In this paper, It is indicating that an issues of the conventional boost converter for high frequency induction heating. To improve those issues, it is proposed, simulated and analyzed that the current resonant circuit, simulated. As the result, we knew that the proposed circuit has a good point to improve the waveform of input current and to make high efficiency. On the other side, in the inverter for the high current power supply, it is proposed that the high frequency inverter of the half bridge topology, be done the circuit analysis to extract the optimal circuit parameter. It is making sure of the soft switching operating by the inductor to reverse parallel connected on the inverter main switch, decreasing the surge voltage when the switch is turn-off by compulsion, and repressing the switch current and bringing the high current amplitude operation by the multi resonance.

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연속 파장 가변시 현상론적인 비 선형 이득 포화 효과가 다전극 DBR 레이저의 변조 특성에 미치는 영향

  • Lee, S.;Park, N.;Park, H. L.;Choi, W. J.;Han, I. K.;Lee, J. I.;Kang, K. N.
    • Korean Journal of Optics and Photonics
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    • v.4 no.3
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    • pp.301-308
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    • 1993
  • Phenomenological nonlinear gain saturation effect on the modulation characteristics in a multi-electrode DBR laser, when the lasing wavelength changes, continuously is analized theoretically. FM efficiency, 3 dB bandwidth, and resonance frequency decrease with increasing bias current to the passive section, except increasing the flat FM response. It is found that the nonlinear gain saturation effect severely affects the modulation characteristics such as FM/IM response, 3 dB bandwidth, resonance frequency and CPR, but hardly affects the behavior of continuous frequency tuning.

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The Conceptual Framework of Building Fashion Brand Equity; Focused on casual wear brand (패션브랜드자산의 형성과정에 관한 연구: 캐주얼 브랜드를 중심으로)

  • 김혜정;임숙자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.2
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    • pp.252-261
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    • 2004
  • In this complex marketing world, marketers find themselves having to grapple with difficult issues about branding and their brand management. In many cases, a deeper understanding of how consumers feel, think, and act could provide valuable guidance to address these brand-management challenges. The objective of this study is to conceptualize and test the framework of building fashion brand equity, utilizing Keller's CBBE Model as a theoretical framework and Kim and Lim's (2002) scale as a measurement model of fashion brand equity. We conducted a survey toward 696 university students using Kim and Lim's fashion brand equity scale. To test the hypothesized building paths of fashion brand equity, statistical analyses were performed with AMOS 4.1 program using confirmatory factor analysis and structural equation model. The results of this study were as follows. First, fashion brand equity was defined in terms of six components; customer-brand resonance, customer feeling, customer judgment, brand imagery. brand performance and brand awareness. Fashion brand equity was multi-dimensional brand attitude, which could be measured by 16 items. Consequently, Kim and Lim's scale acquired a statistical validity. Second, the proposed conceptual framework of this study was partially significant. We can provide an effectiveness of Keller's CBBE model to conceptualize the building process of fashion brand equity. Third, it was different between two brands to build fashion brand equity.

How to Measure Customer Based Brand Equity of Casual wear (캐주얼 브랜드 자산의 측정에 관한 연구)

  • 김혜정;임숙자
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.11
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    • pp.1660-1671
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    • 2002
  • The purpose of this study is to develop and test the casual brand equity measurement, utilizing Heller 5(2001) ‘CBBE(Customer Based Brand Equity) Model' as a theoretical framework. The research was conducted in three steps from May to November in 2001. In the exploratory step, focus-group interview was conducted 5 times for gathering responses related to fashion equity. In Pilot study, 945 university students were surveyed and the data were analyzed to identify the components of fashion brand equity and to develop questionnaires. In the main research, 696 university students evaluated three brands in order to compare their equity that were formed in customers' perception. Statistical analyses were performed with SAS and LISREL 8.12 program using factor analysis and covariance structural equation model. The results were as follows: First, casual brand equity was defined in terms of six components; customer-brand resonance, customer feeling, customer judgment, brand imagery, brand performance and brand awareness. Second, casual brand equity was multi-dimensional brand attitude, which could be measured by 23 items that were different from previous measurement such as Aaker's ‘Brand Equity Ten' and K-BPI.

The polymer waveguide type SPR sensor using a multi-wavelength light source (다파장 광원을 이용한 폴리머 광도파로형 SPR 센서)

  • Park, Chang-Sub;Yeom, Se-Hyuk;Kim, Do-Eok;Kang, Byoung-Ho;Kim, Kyu-Jin;Kim, Hak-Rin;Kang, Shin-Won
    • Journal of Sensor Science and Technology
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    • v.16 no.6
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    • pp.401-406
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    • 2007
  • In this paper, we fabricated the polymer waveguide type surface plasmon resonance (SPR) sensor using a white light source and optical spectrum analyzer (OSA). Fabricated sensor uses the principle of phase matching between evanescent wave and surface plasmon wave. According to the measuring result, the shift of resonance wavelength conducts the change of the refractive index. The proposed SPR sensor is expected to apply the integrated multichannel SPR sensor and the realtime monitoring system.

Solution Structure and Backbone Dynamics of the Biotinylation Domain of Helicobacter pylori Biotin-carboxyl Carrier Protein

  • Jung, Jin-Won;Lee, Chul-Jin;Jeon, Young-Ho;Cheong, Chae-Joon;Lee, Weon-Tae
    • Bulletin of the Korean Chemical Society
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    • v.29 no.2
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    • pp.347-351
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    • 2008
  • Acetyl-CoA carboxylase (ACC) is an excellent candidate for antibiotics drug target, which mediates malonyl-CoA synthesis from acetyl-CoA through acetylation process. It is also involved in the committed step of fatty acid synthesis which is essential for living organisms. We have determined the three dimensional structure of C terminal domain of HP0371, biotin-carboxyl carrier protein of H. pyroli, in solution state using heteronuclear multi-dimensional NMR spectroscopy. The structure of HP0371 shows a flatten b-sheet fold which is similar with that of E. coli. However, the sequence and structure of protruding thumb are different with that of E. coli and the thumb shows different basis of structural rigidity based on backbone dynamics data.

Resonance and Response of the Submerged Dual Buoy/Porous-Membrane Breakwaters in Oblique Seas

  • Kee, S.T.
    • Journal of Ocean Engineering and Technology
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    • v.15 no.2
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    • pp.22-32
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    • 2001
  • The numerical investigation of obliquely incident wave interactions with fully submerged dual buoy/porous-membrane floating breakwaters placed in parallel with spacing is studied based on linear potential theory and Darcy's law. The numerical solutions are obtained by using a discrete-membrane dynamic model and second-kind modified Bessel function distribution over the entire boundaries of fluid regions. First, numerical solutions for an idealized dual submerged system without buoys are obtained. Second, a more practical dual submerged system with membrane tension provided by buoys at its tops is investigated by the multi-domain boundary element method particularly devised for dual buoy/porous-membrane problems with gaps. The velocity potentials of wave motion are coupled with porous-membrane deformation, and solved simultaneously since the boundary condition on porous-membrane is not known in advance. The effects of varying permeability on membranes and wave characteristics are discussed for the optimum design parameters of systems previously studied. The inclusion of permeability on membrane eliminates the resonances that aggravate the breakwater performance. The system is highly efficient when waves generated by the buoys and membranes were mutually canceled and its energy at resonance frequency dissipates through fine pores on membranes.

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The Components of Consumer-Based Fashion Brand Equity (고객평가에 기초한 패션브랜드 자산의 구성요소에 관한 연구)

  • 김혜정;임숙자
    • The Research Journal of the Costume Culture
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    • v.10 no.6
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    • pp.680-696
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    • 2002
  • The aim of this study was to identify the components of customer-based fashion brand equity which was built from customers´perception to equity. As a method, both literature review and empirical research were made. This study performed in three stages from May to November in 2001. In the exploratory step. focus-group interview was conducted 5 times for gathering responses related to fashion brand equity, and free association test of 17 respondents was additionally conducted. In pilot study, 40 university students were surveyed and the data were analyzed in order to identify the components of fashion brand equity and to develop questionnaire. In the main research, 905 university students evaluated fashion brand equity in order to analyze the components of fashion brand equity in customers´perception. Statistical analyses were performed with SAS program using factor analysis, cronbach´α, frequency, and mean. The results of this study was as fellows. First, fashion brand equity was defined in terms of four components; customer-brand resonance, brand imagery/customer feeling, brand performance/customer judgment and brand awareness. Second, fashion brand equity was multi-dimensional brand attitude, which could be measured by 29 variables that were different from uni-dimensional evaluation of previous studies.

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