• Title/Summary/Keyword: CMr

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Colossal Magnetoresistance in Chalcogenide Spinels $Ni_xFe_{1-x}Cr_2S_4(X = 0.05, 0.1, 0.2)$ (Spinel 유화물 $Ni_xFe_{1-x}Cr_2S_4(X = 0.05, 0.1, 0.2)$의 초거대자기저항(CMR)현상에 관한 연구)

  • 박재윤
    • Journal of the Korean Magnetics Society
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    • v.11 no.4
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    • pp.151-156
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    • 2001
  • Recently many studies on manganese oxides Ln$_{1-x}$A$_{x}$MnO$_3$(Ln=La, Pr, Nd lanthannide; A=Ca, Sr, Ba, Pb +2 ions) reported CMR properties. CMR have been also found in chalcogenide spinels. We have investigated that Ni ion substitutions for Fe ion have effects on CMR properties in chacogenide spinels Ni$_{x}$Fe$_{1-x}$Cr$_2$S$_4$. It was found that with increasing Ni concentration Jahn-Teller distortion was strengthened and Curie temperature T$_{c}$ was increased. CMR properties could be explained with Jahnl-Teller effect, half-metallic electronic structure, and the alignment of magnetic domain due to the strong magnetic field, which is different in that double exchange interactions dominate CMR properties in manganese oxides.

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Study on the Palatability, Digestibility and Feeding Behavior in Spotted Deer (Cervus nippon) Fed Forest by-product Silage (육림부산물 발효사료 급여 꽃사슴에 있어서 채식기호성, 소화율 및 채식행동에 관한 연구)

  • 전병태;문상호;이상무;권영재
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.22 no.3
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    • pp.177-186
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    • 2002
  • This experiment was conducted to examine possibility and suitability of forest by-product as a roughage source of deer. As a experimental diet, forest by-product silage(FPS) and commercial mixed ration(CMR) were prepared to compare dry matter intake, digestibility, nitrogen balance and feeding behavior in feeding trials with spotted deer. The digestibility of dry matter was higher(P<0.05) in CMR than in FPS. The digestibility of crude protein was higher in CMR than in FPS and there was significant difference(P<0.05). CMR had more digestibility of crude fiber than FBS but the difference was not significant. Dry matter intake were similar in both diets. Digestible dry matter intake was higher in CMR than FPS, however, there was no significant difference between experimental diets. Nitrogen intake, urinary and digestible nitrogen were significantly higher(P<0.05) in CMR than FPS. The efficiency of nitorgen utilization was higher for FPS than for CMR. Feeding behavior were similar in FPS and CMR. Consequently. It would be expected that FPS that composed with various feed sources can be used as a good roughage source of deer. Because it has high digestibility, dry matter intake and internal availability of nitrogen.

Optimal Cardiac Magnetic Resonance Contrast-Enhanced Timing Robust Angiography (CMR-CENTRA) for the Three-Dimensional Reconstruction of the Bilateral Atria in the Electroanatomic Mapping (EAM) of Atrial Fibrillation

  • Kim, Jun Seong;Oh, Yu-Whan;Shim, Jaemin;Kim, Young-Hoon;Hwang, Sung Ho
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.3
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    • pp.131-138
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    • 2017
  • Purpose: To optimize the timing of scans using cardiac magnetic resonance contrast-enhanced timing robust angiography (CMR-CENTRA) for electroanatomic mapping (EAM) of the right atrium (RA) and left atrium (LA) in patients with atrial fibrillation (AF). Materials and Methods: Fifty patients with AF (38 men; mean age, $59.6{\pm}9.3years$) underwent CMR-CENTRA in preparation for EAM. The CMR-CENTRA data were acquired at five different scan times: 0 seconds, 5 seconds, 10 seconds, 15 seconds, and 20 seconds after an intravenous injection of contrast media. To evaluate the degree of contrast enhancement, right atrial relative contrast (RA-RC) and left atrial relative contrast (LA-RC) on the CMR-CENTRA scans were assessed at each time point. The three-dimensional (3D) reconstruction of the RA and LA for the EAM system was performed using the CMR-CENTRA data. Results: A CMR-CENTRA at a scan time of 10 seconds showed significantly greater LA-RC (P < 0.05) compared with all other scan times. A CMR-CENTRA at a scan time of 15 seconds showed significantly greater RA-RC (P < 0.05) compared with all other scan times. In the 3D reconstruction of the RA, the success rates of CMR-CENTRA at scan times of 10 seconds and 15 seconds were 18% and 100%, respectively. In the 3D reconstruction of the LA, the success rates of CMR-CENTRA at 10- and 15-second scan times were 100%. Conclusion: The CMR-CENTRA data acquired at 15 seconds after the injection of contrast media is appropriate for the preparation of an EAM system that is focused on the RA and LA in patients with AF.

Characteristics on Room temperature CMR Magnetic Material of $La_{2/3-x}{\cdot}Nd_x{\cdot}Sr_{1/3}{\cdot}MnO_3$ ($La_{2/3-x}{\cdot}Nd_x{\cdot}Sr_{1/3}{\cdot}MnO_3$의 상온CMR자기재료(常溫CMR磁氣材料) 특성(特性))

  • Zhe, XianYu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.258-259
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    • 2005
  • 현재 실온특대자기저항효과(室溫特大磁氣抵抗效果(CMR))재료에 관한 연구가 주목 받고 있다. 본 연구는 $LaSrMnO_3$ Magnetite에서 일부 La를 Nd로 치환(置換)한 결과, 사방정 구조를 갖는 실온 CMR 자기재료로써 현저한 CMR 효과가 있음을 확인하였고, 실온범위에서 실용적 응용가치가 있는 평탄한 MR-T 특성을 얻을 수 있음이 관찰되었다.

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Study on Development of Construction Management Module based on Risk factor classification system at Construction Phase (시공단계 위험요소 분류체계 구축을 통한 건설 프로젝트 관리모듈 개발에 관한 연구)

  • Lee, Joo-Sung;Moon, Sung-Kon;Jun, Yeong-Jin;Kim, Ju-Hyung;Kim, Jae-Jun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.05b
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    • pp.199-202
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    • 2009
  • Turn-key and CMF(CM for Fee) have been selected as procurement paths of large public projects in Korea. However, recently, researches and discussions on CMR(CM at Risk) have been popular as the Korean government seeks for alternative procurement paths to enhance the performance. In the CMR projects, the part who is responsible for construction management should predict and control the potential risks for guaranteeing benefits. In this research, CMR projects in which a general contractor plays the role as CMr is mainly analyzed. We give attentions to risk management during construction process given that subcontractors, main parts in this phase, work in various ways and thus more chances for faults exist. In this case, CMr manages risks to control the procedure of project. So, potential risk factors can constitute the database, and that database can be matched to following activity. And construction manager can forecast measures of risk using the result of matching. This chain of activities increase efficiency in roles of CMr on CMR(CM at Risk). Furthermore this study will propose one of the solution of Construction Management Module.

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Application of Carbon-13 NMR spectroscopy to the chemistry of natural products

  • Yamasaki, Kazuo
    • Archives of Pharmacal Research
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    • v.3 no.1
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    • pp.57-64
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    • 1980
  • Carbon-13 NMR spectroscopy(abbreviated CMR) is an extremely powerful strategy for the study of natural organic molecules. The information derivable from CMR is often complementary to that obtianed form proton NMR spectroscopy (PMR). Because of low natural abundance of $^{13}C$ nucleus (1.1%) coupled with low inherent sensitivity relative to $^{1}H$ (about 1/64), CMR experiment is approximately 6000 times less sensitive than PMR. Despite of this, now it is possible to measure CMR of small amount of compound by the development of three significant ingenious techniques, i. e. a) computer time-averaging, b) wide-band (or noise modulated) proton decoupling, and c) pulsed Fourier transform (FT) NMR : For general recognition of CMR, its fundamental aspects of CMR are briefly reviewed.

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Asymmetric Flankers in Comodulation Masking Release

  • Pourbakht, Akram;Faraji, Leila
    • Journal of Audiology & Otology
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    • v.23 no.1
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    • pp.27-32
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    • 2019
  • Background and Objectives: Detection of auditory signals may be improved when maskers far from the frequency of the target signal are coherently amplitude-modulated. This improvement of signal detection is called comodulation masking release (CMR). In the CMR experiments, flankers have been usually arranged symmetrically. In practice, we will be confronted with a problem by using symmetric flankers due to the limited output of clinical audiometers, especially at high-frequency. We aimed to check whether flanker arrangement has any effect on the amount of CMR, especially when there is no flankers with a frequency higher than the signal. Subjects and Methods: Eighteen normal hearing listeners ranging in age from 20 to 46 years old participated. Symmetric (2-2) and asymmetric (3-1 and 4-0) flankers were used and then the amount of CMR compared among them. Results: Our results showed in the same numbers of flankers, there were no statistically CMR differences between symmetric and asymmetric arrangement. Also when we did not have a flanker at a frequency higher than the signal and all flankers were placed below the signal, there was no statistically difference with the symmetric arrangement. Conclusions: The asymmetry of the flankers and also omitting the flankers with a frequency higher than the signal, have no effect on CMR results. We concluded that CMR can be considered by using clinical audiometer.

Asymmetric Flankers in Comodulation Masking Release

  • Pourbakht, Akram;Faraji, Leila
    • Korean Journal of Audiology
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    • v.23 no.1
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    • pp.27-32
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    • 2019
  • Background and Objectives: Detection of auditory signals may be improved when maskers far from the frequency of the target signal are coherently amplitude-modulated. This improvement of signal detection is called comodulation masking release (CMR). In the CMR experiments, flankers have been usually arranged symmetrically. In practice, we will be confronted with a problem by using symmetric flankers due to the limited output of clinical audiometers, especially at high-frequency. We aimed to check whether flanker arrangement has any effect on the amount of CMR, especially when there is no flankers with a frequency higher than the signal. Subjects and Methods: Eighteen normal hearing listeners ranging in age from 20 to 46 years old participated. Symmetric (2-2) and asymmetric (3-1 and 4-0) flankers were used and then the amount of CMR compared among them. Results: Our results showed in the same numbers of flankers, there were no statistically CMR differences between symmetric and asymmetric arrangement. Also when we did not have a flanker at a frequency higher than the signal and all flankers were placed below the signal, there was no statistically difference with the symmetric arrangement. Conclusions: The asymmetry of the flankers and also omitting the flankers with a frequency higher than the signal, have no effect on CMR results. We concluded that CMR can be considered by using clinical audiometer.