• Title/Summary/Keyword: rate dependent

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Parametric Analysis on the Viral Infection in The Rat Circardian Control Center (흰쥐의 일주기조절중추내 바이러스 감염에 대한 매개변수 분석)

  • Kim Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.10 no.2
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    • pp.113-125
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    • 1998
  • The neurotropic psudorabies virus(PRV) to replicate within neurons is very useful pathogen for neuronal tracing. I carried out this study to investigate the parametric analysis on the viral infection in the rat circadian control center with two genetically engineered strains out of PRV. The two strains are isogenic with the attenuated Bartha strain of PRV ; in one strain a lacZ reporter gene was inserted into the gC locus (PRV-BaBlu ; $4.75\times10^8pfu/ml$) and the other strain contained a PRV envelope glycoprotein gene(PRV-D ; $2.5\times10^8pfu/ml$) theat is absent in PRV-BaBlu. simultaneous or temporally separated sequential injection of$2{\mu}l$ of each strain into the vetreous body of eye produced a course of transsynaptic infection of retinohypothalamic circuitry. The results were as follows; 1. PRV-BaBlu and PRV-D infected the suprachiasmatic nucleus in hypothalamus and intergeniculate leaflet in lateral geniculate nucleus of thalamus. 2. The rate of PRV infection was dependent upon PRV strain. 3. Pre-infected neurons by PRV-D were interfered with the replication of PRV-BaBlu. 4. Dual injection of PRV-D and PRV-BaBlu showed more virulent than the parental strain.

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A Study of Localization with Material Properties Using Numerical Method (재료의 특징에 따른 국부화에 대한 수치해석적 연구)

  • 황두순;이병섭;이용성;윤수진;홍성인
    • Transactions of Materials Processing
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    • v.9 no.4
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    • pp.395-403
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    • 2000
  • Formation of Shear Band under the adiabatic condition is widely observed In the engineering materials during rapidly forming process lot a thermally rate-dependent material. The shear band stems from evolution of a narrow region in which an intensive plastic flow occurs. The shear band often plays a role of a precursor of the ductile fracture during a forming process. The objective of this study is to investigate the localization behavior using numerical method. In this work, the implicit finite difference scheme is employed due to the ease of convergence and the numerical stability It is noted that physical and mechanical properties of materials determine how the shear band is formed and then localized. Material properties can be characterized with inertia number dissipation number and diffusion number. It is observed that the dimensionless numbers effect on localization. Using a parametric study, comparison was made between CRS-1018 steel with WHA (tungsten heavy alloy). The deformation behavior of material in this study include an isotropic hardening as well as thermal softening. Moreover, this study suggests that a kinematic hardening constitutive relation be required to predict a more accurate strain level at a shear band.

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A Study of Estimation of the Arc Stability in Short-circuition Transfer Region of GMA Welding Using Multi-layer Perceptrons (다층 신경회로망을 이용한 GMA 용접 단락이행영역에서의 아크 안정성 평가)

  • 강문진;이세헌;엄기원
    • Journal of Welding and Joining
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    • v.17 no.5
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    • pp.98-106
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    • 1999
  • In GMAW, the spatters are generated according to the variation of the arc. Of the arc is stable, Few spatters are generated. But if unstable, too many spatters are generated. So, this means the spatters are dependent on the arc state. The aim of this study is to accurately estimate the arc state. To do this, the generated spatters were captured under the some welding conditions, and the waveforms of the arc voltage and welding current were collected. From the collected signals, the waveform factors and their standard deviations were extracted. Using these factors as input parameters of multi-layer artificial neural network, the learning for the weight of the generated spatters is performed and the estimation results to the real spatter are assessed. Obtained results are as follow: the linear correlation coefficient between the estimated result and the real spatters was 0.9986. And although the average convergence error was set 0.002, the estimated error to the real spatter was within 0.1 gr/min at each welding condition. In the estimation for the weight generated spatters, the result with multi-layer neural network was far better than with multiple regression analysis. Especially, even though under the welding condition which the arc state is unstable (the spatter is generated much more), very excellent estimation performance was shown.

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Immunostimulating Effect of Mycelium Extract of Phellinus linteus (상황버섯 균사체 추출물의 면역증진 효능)

  • Lee, Byung-Eui;Ryu, Shi-Yong;Kim, Eui-Han;Kim, Young-Hee;Kwak, Kyung-A;Song, Ho-Yeon
    • Korean Journal of Pharmacognosy
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    • v.43 no.2
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    • pp.157-162
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    • 2012
  • In order to investigate the immunostimulating effect of mycelia extract of Phellinus linteus (PLM) on human monocyte THP-1 and rat peritoneal macrophage cell, we examined measuring cytokine secretion (IL-6 and TNF-${\alpha}$). The production of IL-6 and TNF-a in human monocyte THP-1 was slight increased dose-dependently when the cells were challenged with PLM for 72 hrs. It was also observed that the treatment of PLM with LPS augmented the production of IL-6 and TNF-a in human monocyte THP-1. It was also observed that the treatment of PLM with LPS augmented the production of IL-6 and TNF-${\alpha}$ in human monocyte THP-1. The production of IL-6 and TNF-${\alpha}$ in rat peritoneal macrophage was significantly enhanced when the cells were treated PLM with LPS for 72 hrs. Moreover, the proliferation rate of rat spleen cells was increased in a dose dependent manner as the cells were treated with PLM and Concanavalin A.

Locally Optimum Detection of Signals in first-order Markov Environment: 1. Test Statistics (일차 마르코프 잡음 환경에서의 국소 최적 검파: 1. 검정 통계량)

  • Lee, Ju-Mi;Park, Ju-Ho;Song, Iic-Ho;Kwon, Hyoung-Moon;Kim, Jong-Jik;Yoon, Seok-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10C
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    • pp.973-980
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    • 2006
  • In most of the studies on locally optimum detection assumes independent observations. The use of an independent observation model may cause a considerable performance degradation in detection applications of modern high data rate communication systems exhibiting dependence among interference components. In this paper, we address the detection of weak known signals in multiplicative and first order Markov additive noises. In Part 1, the test statistics of the locally optimum detectors are investigated in detail. In Part 2, the asymptotic and finite sample-size performance of several detectors are obtained and compared, confirming that the dependence among interference components need to be taken into account to maintain performance appropriately.

The Performance Evaluation of Extended Phase Recovery Algorithm for OQPSK in Satellite Channel (위성 채널에서 확장된 OQPSK 위상동기 알고리즘 성능평가)

  • 김명섭;송윤정;정지원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.5A
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    • pp.634-640
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    • 2000
  • This paper proposes a new extended decision directed-decision estimated phase recovery algorithm based on maximum likelihood parameter estimation for OQPSK. In this scheme, comparing conventional one, the data dependent noise of phase recovery loop is reduced by inserting filter with 2 taps to in-phase and quadrature-phase channel respectively before phase detector. The proposed scheme is compared to conventionalscheme and OQPSK in aspect to BER(Bit Error Rate) and phase error according to the roll-off factor of baseband filter, the output back-offs of nonlinear satellite channel, and loop bandwidth.

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Synthesis of Aniline from Nitrobenzene and Fe(CO)5 with Polyethyleneglycol as Phase Transfer Catalyst (폴리에틸렌글리콜 상이동 촉매상에서 니트로벤젠과 Fe(CO)5로부터의 아닐린 합성)

  • Oh, So-Young;Chun, Sung-Woo;Park, Dae-Won;Park, Sang-Wook;Shin, Jung-Ho
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.620-626
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    • 1992
  • PEG phase transfer catalyzed reduction of nitrobenzene with $Fe(CO)_5$ afforded aniline up to over 50% yield al room temperature. The reaction rate of nitrobenzene was dependent on the chain length and number of binding sites of PEG, and it was increased with the concentration of NaOH and solvent polarity. But the yield of aniline was maximum) with 2N NaOH solution and it was decreased at higher concentrations.

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Design of Metal Cored Wire for Erosion Resistant Overlay Welding

  • Kim, Jun-Ki;Kim, In-Ju;Kim, Ki-Nam;Kim, Ji-Hui;Kim, Seon-Jin
    • Proceedings of the KWS Conference
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    • 2009.11a
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    • pp.202-204
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    • 2009
  • Erosion is a common failure mode of materials frequently encountered in plant and power industry. Although the erosion resistance of Fe-base alloy has been inferior to the other expensive materials, it is expected that the strain-induced martensitic transformation can impart high erosion resistance to Fe-base alloy. The key technology to develop Fe-base metal cored welding wire for erosion resistant overlay welding may include the strain-induced metallurgy for hardening rate control and the welding flux metallurgy for dilution control. Sophisticated studies showed that the strain-induced martensitic transformation behavior was related to the critical strain energy which was dependent on the alloy composition. Dilution and bead shape of overlay weld were proved to be affected by metal transfer mode during gas tungsten arc welding and elements in welding fluxes. It was considered that the highly erosion resistant Fe-base overlay weld could be achieved by precise control of alloy composition to have proper level of critical strain energy for energy absorption and welding flux formulation to have small amount of deoxidizing metallic elements for dilution.

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The Adhesion Promotion of Glass Fiber Reinforced Composite Using Methacrylate Functional Silanes (메타아크릴레이트 실란을 이용한 유리섬유 강화복합재료의 물성향상)

  • Jang, Jyong-Sik
    • Applied Chemistry for Engineering
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    • v.1 no.2
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    • pp.133-139
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    • 1990
  • Methacrylate functional silanes with different methylene spacer groups have been synthesized and the orientation effect and absorption behavior of these silane coupling agent were investigated by Fourier transform infrared spectroscopy(FT-IR). The mechanical properties of glass bead/polyester composites are found to be dependent on the spacer group of treated silane coupling agent. The absorption rate of the silane coupling agent onto the fumed silica surface decreases with increasing the number of the methylene spacer in methacrylate functional silanes. Silane molecules containing long spacer groups are adsorbed onto silica slightly bowed with respect to the substrate surface. The relationship between silane molecular structure and mechanical properties of polymer composites is also investigated in order to improve hot/wet properties of glass fiber/polyester composites.

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Effects of Phytic Acid Content, Storage Time and Temperature on Lipid Peroxidation in Muscle Foods (근육식품에서 지방산화에 대한 피틴산, 저장기간 및 온도의 영향)

  • 이범준;김영철;조명행
    • Journal of Food Hygiene and Safety
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    • v.14 no.1
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    • pp.27-33
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    • 1999
  • Phytic acid, making up 1~5% of the composition of many plant seeds and cereals, is known to form iron-chelates and inhibit lipid peroxidation. Thiobarbituric acid reactive substances (TBARS), as an indication of lipid peroxidation, were measured in beef round, chicken breast, pork loin, and halibut muscle after the meats were stored for 0, 1, 3, 5, and 7 days at various temperatures [frozen (~2$0^{\circ}C$), refrigerator (4$^{\circ}C$), and room temperature ($25^{\circ}C$)]. Phytic acid effectively inhibited lipid peroxidation in beef round, chicken breast, halibut, and pork loin muscle (p<0.05). The inhibitory effect of phytic acid was dependent on concentration, storage time, and temperature. At frozen temperature, the inhibitory effect of phytic acid was minimal, whereas at room temperature, the inhibitory effect of phytic acid was maximal, probably due to the variation of the control TBARS values. At the concentration of 10 mM, phytic acid completely inhibited lipid peroxidation in all the muscle foods by maintaining TBARS values close to the level of the controls, regardless of storage time or temperature (p<0.05). The rate of lipid peroxidation was the highest in beef round muscle, although they had a close TBARS value at 0 day. Addition of phytic acid to lipid-containing foods such as meats, fish meal pastes, and canned seafoods may prevent lipid peroxidation, resulting in improvement of the sensory quality of many foods and prolonged shelf-life.

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