• Title/Summary/Keyword: NEm

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Free Vibration and Dynamic Response Analysis by Petrov-Galerkin Natural Element Method

  • Cho, Jin-Rae;Lee, Hong-Woo
    • Journal of Mechanical Science and Technology
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    • v.20 no.11
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    • pp.1881-1890
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    • 2006
  • In this paper, a Petrov-Galerkin natural element method (PG-NEM) based upon the natural neighbor concept is presented for the free vibration and dynamic response analyses of two-dimensional linear elastic structures. A problem domain is discretized with a finite number of nodes and the trial basis functions are defined with the help of the Voronoi diagram. Meanwhile, the test basis functions are supported by Delaunay triangles for the accurate and easy numerical integration with the conventional Gauss quadrature rule. The numerical accuracy and stability of the proposed method are verified through illustrative numerical tests.

Stochastic Finite Element Aalysis of Space Truss by Neumann Expansion Method (뉴우먼 확장법에 의한 3차원 트러스의 확률유한요소해석)

  • 정영수;김기정
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1993.04a
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    • pp.117-124
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    • 1993
  • The Neumann Expansion method has been used for evaluating the response variability of three dimensional truss structure resulting from the spatial variability of material properties with the aid of the finite element method, and in conjunction with the direct Monte Carlo simulation methods. The spatial variabilites are modeled as three-dimensional stochastic field. Yamazaki 〔1〕 has extended the Neumann Expansion method to the plane-strain problem to obtain the response variability of 2 dimensional stochastic systems. This paper presents the extension of the Neumann Expansion method to 3 dimensional stochastic systems. The results by the NEM are compared with those by the deterministic finite element analysis and by the direct Monte Carlo simulation method

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An Effective Noise Estimator for Use in Noise Reduction

  • Han, Hag-Yong;Kwon, Ho-Min;Lee, Sung-Mok;Lee, Gi-Dong;Kang, Bong-Soon
    • Journal of information and communication convergence engineering
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    • v.9 no.1
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    • pp.59-63
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    • 2011
  • Conventional noise reduction filtering schemes realize limited improvements of the peak signal-to-noise ratio (PSNR) in the low-level noisy images. The flatness degree and the edge information are effectively used to estimate the noise volume. We propose a noise estimator for reducing noise in the AWGN (additive white gaussian noise) corrupted images using three intermediate image maps (FGM(flatness gray map), FIM(flatness index map), NEM(noise estimate map)). The proposed noise estimator is fed into the conventional noise reduction filters as a pre-processor. The performance of noise reduction is tested in the various AWGN corrupted images.

World Report - Levelized Cost and Levelized Avoided Cost of New Generation Resources in the Annual Energy Outlook 2017 (균등화 발전 비용과 균등화 회피 비용을 이용한 신규 발전원의 경제성 비교)

  • 한국원자력산업회의
    • Nuclear industry
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    • v.37 no.8
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    • pp.38-57
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    • 2017
  • 이 보고서는 2019년, 2022년, 그리고 2040년에 가동에 들어가는 신규 발전원들의 균등화 발전 비용과 균등화 회피 비용의 평균값이 얼마나 되는지를 보여주는 데 그 목적이 있다. 이 보고서에 나온 자료는 Annual Energy Outlook 2017(AEO2017)를 작성하는 데 이용된 National Energy Modeling System(NEMS)에 있는 것들이다. 세 가지의 시나리오 중에서 2022년 가동에 들어가는 경우에 대해서만 본문에서 다루었고, 나머지 2019년과 2040년 가동에 들어가는 경우에 대해서는 각각 부록 A와 B에서 다루었다. 계산은 NEMS의 전력시장 모듈(EMM)에 들어 있는 미국의 22개 지역에 건설되는 발전 설비들을 대상으로 하고 있다. 이 보고서는 그 22개 지역 발전 설비들의 평균 균등화 발전 비용, 설비 용량을 고려한 가중 평균 비용, 지역 간 비용 편차, 그리고 균등화 회피 비용과 균등화 발전 비용의 차이 등을 계산하여 제시하고 있다.

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NMR Signal Assignments of the Stereochemical Cycloadducts of Bicyclolactone via Diels-Alder Reaction

  • Kim, Dae-Sung;Seo, Chan-Woo;Cho, Cheon-Gyu;Won, Ho-Shik
    • Journal of the Korean Magnetic Resonance Society
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    • v.8 no.1
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    • pp.62-69
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    • 2004
  • Bicyclolactones obtained from the Diels-Alder cycloaddition of 3,5-dibromo-2-pyrone can undergo various palladium catalyzed cross coupling reactions to afford aryl bicyclolactones. The resulting coupled products can be readily converted into various 3-OH cyclohexenes via lactone ring openings, while those bearing dienyl units underwent highly diastereoselective Diels-Alder cycloadditions with selected dienophiles to funish multiply functionalized polycarbocycles. Bromo-bicyclic diene furnished two different diastereomers endo-form (62%) and exo-form (38%) upon cycloadditions with N-Et maleimide (NEM), and their stereochemistries were identified with NMR.

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Advanced two-level CMFD acceleration method for the 3D whole-core high-fidelity neutron adjoint transport calculation

  • Zhu, Kaijie;Hao, Chen;Xu, Yunlin
    • Nuclear Engineering and Technology
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    • v.53 no.1
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    • pp.30-43
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    • 2021
  • In the 2D/1D method, a global adjoint CMFD based on the generalized equivalence theory is built to synthesize the 2D radial MOC adjoint and 1D axial NEM adjoint calculation and also to accelerate the iteration convergence of 3D whole-core adjoint transport calculation. Even more important, an advanced yet accurate two-level (TL) CMFD acceleration technique is proposed, in which an equivalent one-group adjoint CMFD is established to accelerate the multi-group adjoint CMFD and then to accelerate the 3D whole-core adjoint transport calculation efficiently. Based on these method, a new code is developed to perform 3D adjoint neutron flux calculation. Then a set of VERA and C5G7 benchmark problems are chosen to verify the capability of the 3D adjoint calculations and the effectiveness of TL CMFD acceleration. The numerical results demonstrate that acceptable accuracy of 2D/1D adjoint calculations and superior acceleration of TL CMFD are achievable.

Studies on the Possible Utilization of Diplachne fusca L. as a Forage Crop II. Growth Characteristics, Forage Yield and Quality of Diplachne fusca L. (바다새 (Diplachne fusca L.) 의 사료작물화 가능성에 관한 연구 II. 바다새의 생육특성, 사초수량 및 사료가치)

  • 김창호;양주훈;이효원
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.18 no.3
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    • pp.179-186
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    • 1998
  • This experiment was conducted to study on forage utility of Diplachne fusca L. which live in reclaimed saline land of midwest region of Korea The secondary experiment was conducted to know on growth characteristics, forage yield and forage value of Diplachne fusca L. in order to get a necessary data on possible utilization of native plant as a forage crop and practical use of reclaimed saline land. The results obtained are summarized as follows; 1. The growth of Diplachne fusca L. was neary finished at heading stage. So plant height, leaf length, leaf width, stem diameter, tillering number, fresh weight and dry weight per plant were 137.5cm, 42.6cm, 4.65mm, 2.48mm, 15.3 tiller, 44.68 and 15.3g respectively. 2. Fresh weight was the highest with 4,460kg/10a at heading stage, dry weight was 1,530kg/10a at heading stage and 1,630kg/10a at 20 day after heading. The fresh weight was significantly difference between cutting height level according to cutting time, but total fresh weight was not significantly difference between cutting height level. Total dry weight was significantly difference between cutting height, so it was a large yield at cutting height of 10cm. 3. The contents of crude protein, available protein, digestible protein and TDN were the range of 12.3~3.7%, 12.3~3.7% 10.8~3.6% and 65.2~60.7% according to growth stage, respectively. The highest yield of crude protein, available protein, and digestible protein were showed at heading stage, that of TDN showed at 20 day after heading. The contents of ADF and NDF were the range of 36.4~50.0% and 62.7-80.5% according to growth stage. 4. The contents of P, Ca, K and Mg were the range of 0.31~0.20, 0.70~0.52, 1.74~1.28 and 0.19~0.18% according to growth stage, respectively. The highest yield of P, Ca and K was showed at heading stage, that of Mg showed at 20 day after heading. 5. The contents of ENE, NEL, NEM and NEG were the range of 1.42~1.29, 0.68~0.62, 0.68~0.61 and 0.40~0.35 McaVlb according to growth stage, respectively. The highest yield of ENE, NEL, NEM and NEG was showed at 20 day after heading by inuease after heading. 6. The grasseating ratio of Diplachne fusca L. of before and after heading by milk cattle was 96.5% and 95.3%, respectively.

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A Study on the Post-Receptor Mechanism of Adenosine Receptor on Acetylcholine Release in the Rat Hippocampus (흰쥐 해마에서 Acetylcholine 유리에 관여하는 Adenosine Receptor의 Post-Receptor 기전에 관한 연구)

  • Choi, Bong-Kyu;Oh, Jae-Hee
    • The Korean Journal of Pharmacology
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    • v.30 no.3
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    • pp.263-272
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    • 1994
  • Since it was been reported that the depolarization-induced ACh release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the ACh release has not been clearly elucidated yet. Therefore, it was attempted to clarify the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of ACh release in this study. Slices from rat hippocampus were equilibrated with $^3H-choline$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $VCm^{-1}$, 2ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $0.3{\sim}300\;{\mu}M$, decreased the ACh release in a dose-dependent manner, without affecting the basal rate of release. The adenosine effects were significantly inhibited by $DPCPX\;(2\;{\mu}M)$, a selective $A_1-receptor$ antagonist. The responses to N-ethylmaleimide $(10&30{\mu}M)$, a SH-alkylating agent of G-protein, were characterized by increments of the evoked ACh-release and the basal release, and the adenosine effects were completely abolished by NEM pretreatment. PDB $(1{\sim}10\;{\mu}M)$, a specific protein kinase C (PKC) activator, increased, whereas PMB $(0.03{\sim}1\;mg)$, a PKC inhibitor, decreased the evoked ACh-release, and the adenosine effects were not affected by these agents. Nifedipine $(1\;{\mu}M)$, a $Ca^{2+}\;-channel$ blocker of dihydropyridine analogue, significantly inhibited the adenosine effect, but glibenclamide, a $K^+-channel$ blocker, did not. Finally, 8-bromo cyclic AMP $(100\;&\;300{\mu}M)$, a membrane-permeable analogue of cAMP, did not alter the ACh release, but adenosine effects were inhibited by pretreatment with large dose of 8-br-cAMP $(300\;{\mu}M)$. These results indicate that the decrement of the evoked ACh-release by $A_1-adenosine$ receptor is mediated by the G-protein, and nifedipine-sensitive $Ca^{2+}-channel$ and adenylate cyclase system are coupled partly to this effect, and that protein kinase C and glibenclamide-sensitive $K{^+}-channel$ are not involved in this process.

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THE ENERGY VALUE OF RICE STRAW FOR RUMINANTS AS INFLUENCED BY TREATMENT WITH ANHYDROUS AMMONIA OR MIXING WITH ALFALFA

  • Han, I.K.;Ha, J.K.;Garrett, W.N.;Hinman, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.2 no.2
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    • pp.115-121
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    • 1989
  • A comparative slaughter feeding experiment with steer calves weighing 280 kg and a concurrent digestion trial with wether lambs was conducted to study the energy value of rice straw as influenced by ammonia treatment and mixing with alfalfa hay. Steers were ad libitum fed one of nine completely mixed experimental diets: basal (high concentrate); 25 or 50% of untreated rice straw (URS) or ammoniated (plastic covered bales, 4.6% $NH_3$ by weight) rice straw (ARS) proportionately replacing part of the basal; a 50:50 % mixture of URS or ARS and alfalfa replacing a proportion of the basal at 25 and 50%. Digestibility of the nine complete diets (pelleted to prevent sorting) was determined with four ad libitum fed lambs. Ammoniation increased crude protein level (from 3.6 to 10.8%) and in vitro dry matter digestibility of the rice straw by 15%. The improvement in DE, NEm and NEg by ammoniation of rice straw was 20, 52 and 117%, respectively. Ammoniation of rice straw fed as 50% of the diet improved gains over the diet containing 50% URS, but no significant influence on animal performance was observed when rice straw was fed at the 25% level. Each 10% addition of URS to basal diet decreased empty body gain of steers by 116 gram per day compared with a decrease of 70 gram per day when rice straw had been ammoniated. There was no beneficial effect of ammoniation when the roughage component of the diet was a 50:50 mixture of rice straw and alfalfa. Ammoniation of straw and inclusion of alfalfa generally increased the concentration of total volatile fatty acids in rumen fluid. Ammoniation resulted in reduced concentrations of acetic and propionic acid, but increased concentration of butyric acid. Digestibility of URS was improved by mixing with alfalfa. However, alfalfa hay did not influence digestibility of ARS. Diets in which ARS replaced the basal mixture at 25 and 50% had higher NEm and NEg values than comparable URS diets. The same pattern was observed in the straw: alfalfa mixtures, but differences between URS and ARS were significant only for the 50% roughage diets.

Degradations of human immunoglobulins and hemoglobin by a 60 kDa cysteine proteinase of Trichomonas vaginalis (질편모충의 60 kDa 시스테인 단백분해효소의 인체 면역글로불린 및 헤모글로빈 분해능)

  • Duk-Young MIN;Keun-Hee Hyun;Jae-Sook Ryu;Myoung-Hee AHN;Myung-Hwan CHO
    • Parasites, Hosts and Diseases
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    • v.36 no.4
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    • pp.261-268
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    • 1998
  • The present study was undertaken to investigate the role of cysteine proteinase of Trichomonas vaginalis in escaping from host defense mechanism. A cysteine proteinase of T. vaginalis was purified by affinity chromatography and gel filtration. Optimum pH for the purified proteinase activity was 6.0. The proteinase was inhibited by cysteine and serine proteinase inhibitors such as E-64, NEM, IAA, leupeptin. TPCK and TLCK, and also by $Hg^{2+}$, but not affected by serine-, metallo-, and aspartic proteinase inhibitors such as PMSF, EDTA and pepstatin A. However, it was activated by the cysteine proteinase activator, DTT. The molecular weight of a purified proteinase was 62 kDa on gel filtration and 60 kDa on SDS-PAGE. Interestingly, the purified proteinase was able to degrade serum IgA, secretory IgA, and serum IgG in time- and dose-dependent manners. In addition, the enzyme also degraded hemoglobin in a dose-dependent manner. These results suggest that the acidic cysteine proteinase of T. vaginalis may play a dual role for parasite survival in conferring escape from host humoral defense by degradation of immunoglobulins, and in supplying nutrients to parasites by degradation of hemoglobin.

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