• Title/Summary/Keyword: Rho A

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Predistorter Design for a Memory-less Nonlinear High Power Amplifier Using the $rho$th-Order Inverse Method for OFDM Systems ($rho$차 역필터 기법을 이용한 OFDM 시스템의 메모리가 없는 비선형 고전력 증폭기의 전치 보상기 설계)

  • Lim, Sun-Min;Eun, Chang-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.2C
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    • pp.191-199
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    • 2006
  • In this paper, we propose a method to implement a predistorter of the $rho$-th order inverse filter structure to prevent signal distortion and spectral re-growth due to the high PAPR (peak-to-average ratio) of the OFDM signals and the non-linearity of high-power amplifiers. We model the memory-less non-linearity of the high-power amplifier with a polynomial model and utilize the inverse of the model, the $rho$-th order inverse filter, for the predistorter. Once the non-linearity is modeled with a polynomial, since we can determine the $rho$-th order inverse filter only with the coefficients of the polynomial, large memory is not required. To update the coefficients of the non-linear high-power amplifier model, we can use LMS or RLS algorithms. The convergence speed is high since the number of coefficients is small, and the computation is simple since manipulation of complex numbers is not necessary.

Differentially Expressed Proteins in ER+ MCF7 and ER- MDA-MB-231 Human Breast Cancer Cells by RhoGDI-α Silencing and Overexpression

  • Hooshmand, Somayeh;Ghaderi, Abbas;Yusoff, Khatijah;Thilakavathy, Karuppiah;Rosli, Rozita;Mojtahedi, Zahra
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.7
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    • pp.3311-3317
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    • 2014
  • Background: The consequence of Rho GDP dissociation inhibitor alpha (RhoGDI${\alpha}$) activity on migration and invasion of estrogen receptor positive ($ER^+$) and negative ($ER^-$) breast cancer cells has not been studied using the proteomic approach. Changes in expression of RhoGDI${\alpha}$ and other proteins interacting directly or indirectly with RhoGDI${\alpha}$ in MCF7 and MDA-MB-231, with different metastatic potentials is of particular interest. Materials and Methods: $ER^+$ MCF7 and ER- MDA-MB-231 cell lines were subjected to two-dimensional electrophoresis (2-DE) and spots of interest were identified by matrix-assisted laser desorption/ionization time of- flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry (MS) analysis after downregulation of RhoGDI${\alpha}$ using short interfering RNA (siRNA) and upregulated using GFP-tagged ORF clone of RhoGDI${\alpha}$. Results: The results showed a total of 35 proteins that were either up- or down-regulated in these cells. Here we identifed 9 and 15 proteins differentially expressed with silencing of RhoGDI${\alpha}$ in MCF-7 and the MDA-MB-231 cells, respectively. In addition, 10 proteins were differentially expressed in the upregulation of RhoGDI${\alpha}$ in MCF7, while only one protein was identified in the upregulation of RhoGDI${\alpha}$ in MDA-MB-231. Based on the biological functions of these proteins, the results revealed that proteins involved in cell migration are more strongly altered with RhoGDI-${\alpha}$ activity. Although several of these proteins have been previously indicated in tumorigenesis and invasiveness of breast cancer cells, some ohave not been previously reported to be involved in breast cancer migration. Hence, these proteins may serve as useful candidate biomarkers for tumorigenesis and invasiveness of breast cancer cells. Conclusions: Future studies are needed to determine the mechanisms by which these proteins regulate cell migration. The combination of RhoGDI${\alpha}$ with other potential biomarkers may be a more promising approach in the inhibition of breast cancer cell migration.

ON THE MARTINGALE EXTENSION OF LIMITING DIFFUSION IN POPULATION GENETICS

  • Choi, Won
    • Korean Journal of Mathematics
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    • v.22 no.1
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    • pp.29-36
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    • 2014
  • The limiting diffusion of special diploid model can be defined as a discrete generator for the rescaled Markov chain. Choi([2]) defined the operator of projection $S_t$ on limiting diffusion and new measure $dQ=S_tdP$. and showed the martingale property on this operator and measure. Let $P_{\rho}$ be the unique solution of the martingale problem for $\mathcal{L}_0$ starting at ${\rho}$ and ${\pi}_1,{\pi}_2,{\cdots},{\pi}_n$ the projection of $E^n$ on $x_1,x_2,{\cdots},x_n$. In this note we define $$dQ_{\rho}=S_tdP_{\rho}$$ and show that $Q_{\rho}$ solves the martingale problem for $\mathcal{L}_{\pi}$ starting at ${\rho}$.

Elicitor-induced Phenylalanine-Ammonia Lyase, Cinnamic Acid 4-Hydroxylase and $rho-Coumaroyl$ transferase Activity in Ephedra Distachya Cultures

  • Song, Kyung-Sik;Yutaka Ebizuka
    • Archives of Pharmacal Research
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    • v.19 no.3
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    • pp.219-222
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    • 1996
  • Ephedra olistachya cultures have been known to accumulate $rho-coumaroylamino$ acids by elicitor treatment. Based on their chemical structures, the biosynthetic pathway of$rho-coumaroylamino$acids was postulated and phenylalanine ammonia-lyase (PAL), cinnamic acid 4-hydroxylase (4-CH) and p-coumaroyl CoA: D-Ala p-coumaroyltransferase ($rho-CT$) were supposed to be involved in the pathway. The time course inductions of these enzymes were investigated after treatment of yeast extract, yeast-derived mannan glycopeptide and D-Ala. They were detectable at only 4 hours and reached to their maximum level at 9 hours after onset of elicitor treatment. The activities of PAL and 4-CH were almost disappeared within 24 hours, however, that of $rho-CT$was remained up to 48 hours irrespective of the kind of elicitors. $rho-CT$ showed substrate specificity to D-Ala at crude enzyme extract level.

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Satisfaction of continuing education and need assessment according to job characteristics in emergency medical technicians (응급구조사의 업무 특성에 따른 보수교육 만족도 및 교육요구도)

  • Park, Jung-Hee;Yoon, Byoung-Gil
    • The Korean Journal of Emergency Medical Services
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    • v.22 no.2
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    • pp.79-91
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    • 2018
  • Purpose: To assess the satisfaction of continuing education and need assessment according to job characteristics in emergency medical technicians (EMTs). Methods: A self-reported questionnaire was completed by 222 EMTs from May 28 to July 6, 2018. It consisted of questions on the method and need of continuing education, and satisfaction regarding education time, assessed using a 5-point Likert scale. Descriptive statistics, a chi-square test, and ANOVA were used to analyze the data. Results: The responses to questions on the method of continuing education (${\rho}=.000$), satisfaction of regarding the duration of continuing education (${\rho}=.029$), method (${\rho}$< .001), and topic (${\rho}=.000$) varied according to the differences in job characteristics of EMTs. Assessment and management of patients with multiple trauma ($4.17{\pm}.735$) emerged as the most important while license examination protocol for EMTs ($3.33{\pm}.968$) was rated the least important among topics for continuing education. Separation of continuing education (${\rho}$< .001), education method (${\rho}$< .001), education topic (${\rho}$< .001), and necessity of quality management of continuing education (${\rho}$< .001) differed according to the job characteristics of EMTs. Conclusion: It is important to provide a suitable program catering to the diverse requirements of EMTs. The education programs must be tailored to the needs of level 1 and level 2 EMTs separately. To improve the quality of education, it is necessary to evaluate the continuing effects.

Correlation Development on Critical Power in a Spherical Narrow Gap (구형 간극에서의 임계 출력에 대한 상관식 개발)

  • Park, Rae-Joon;Ha, Kwang-Soon;Kim, Sang-Baik;Kim, Hee-Dong;Jeong, Ji-Hwan
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.235-240
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    • 2001
  • The CHFG (Critical Heat Flux in Gap) test results have been evaluated to quantify the critical power in hemispherical narrow gaps and a new correlation has been developed. The CHFG test results have shown that increases in the gap thickness and pressure lead to an increase in critical power. The pressure effect on the critical power was found to be much milder than predictions by CHF correlations of other researches. From the CHFG test results, a new correlation on critical power in the hemispherical gap has been developed using the non-dimensional parameters as follows: $$\frac{qCHF}{{\rho}g^hfg}{\cdot}4\sqrt{\frac{{\rho}_g^2}{g{\sigma}{\Delta}{\rho}}=\frac{0.1042}{1+0.1375({\rho}g/{\rho}l)^{0.21}(D/s)}$$ The developed correlation has been expanded to apply the spherical geometry using the Siemens/KWU's correlation.

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COMPARISON OF $\rho-ADIC$ THETA FUNCTIONS

  • Sung Sik Woo
    • Bulletin of the Korean Mathematical Society
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    • v.38 no.3
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    • pp.427-434
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    • 2001
  • In this paper we investigate how $\rho-adic\;\theta$\theta$-function$ of Neron and Tate are related. As a result, we show that the $\rho-adic$ theta function defined by Neron and that defined by Tate are differ by an analytic function whose values are units.

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THE VARIATIONAL THEORY OF A CIRCULAR ARCH WITH TORSIONAL SPRINGS AT BOTH EDGES

  • Go, Jae-Gwi
    • Journal of the Korean Mathematical Society
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    • v.44 no.3
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    • pp.707-717
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    • 2007
  • Arches are constrained with rotational resistance at both edges. An energy method is used to derive variational formulation which is used to prove the existence of equilibrium states of elastic circular arches for the torsional spring constants ${\rho}-\;{\geq}\;0,\;{\rho}+\;{\geq}\;0,\;and\;{\rho}-\;+\;{\rho}+\;>\;0$. The boundary conditions are searched using the existence of minimum potential energy.

An Experimental Study on the Flexural Ductility of Doubly Reinforced Concrete Beams with Different Concrete Strength (콘크리트 압축강도변화에 따른 철근 콘크리트 보의 휨연성 거동에 관한 실험적연구)

  • 박승종;김용부
    • Journal of the Korea Concrete Institute
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    • v.11 no.3
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    • pp.131-140
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    • 1999
  • This paper presents a study on the flexural ductility of reinforced concrete beams, 16beams with different concrete strength, reinforcement ratio, reinfo- rcement strength. For the purpose of inducing flexural failure, the reinforce ratio ($\rho$-$\rho$') was made not to be more than $0.75\rho$b in accordance with ACi code 318-89. From the test results, it is found that in case of a concrete strength increased from 240 to 650kg/$\textrm{cm}^2$, the displacement and curvature ductility factore are increased by about 31-231 percents. And also increased in case of increased from 650 to 900kg/$\textrm{cm}^2$, but the increasing ratio is gradually decreasing accoding to a concrete strength increases. And also found that as the Double Re-bar Ratio (($\rho$-$\rho$')/$\rho$b) increases, so the displacement and curvature ductility ratio would decrease, but in case of increased from 650 to /$900kg\textrm{cm}^2$ the decreasing ration is bigger than in case of increased from 240 to $650kg/\textrm{cm}^2$.

Relationship between Maximum Stem Volume and Density during a Course of Self-thinning in a Cryptomeria japonica Plantation

  • Ogawa, Kazuharu;Hagihara, Akio
    • The Korean Journal of Ecology
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    • v.27 no.1
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    • pp.27-33
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    • 2004
  • Cryptomeria japonica plantation was monitored every year during 15 years from 1983 to 1997 for stem diameter and volume. The reciprocal equation, 1/Y = A + B/N, was applied to the relationship between cumulative volume Y and cumulative number N from the largest tree in the stand each year. The parameters A and B, which means respectively the reciprocal of an asymptotic value of total stand stem volume and the reciprocal of the maximum stem volume, are related by a power function. The power functional relationship between A and B derived a linear relationship of B-points ( $N_{B}$, $V_{B}$; $N_{B}$ = B/A, $Y_{B}$ = 1/2A) of each Y-N curve on log-log coordinates. The gradient of B-point line was so steep that the Y-N curve moved parallel upward year by year. The time trajectory of mean stem volume (W) and density ($\rho$) provided evidence in favor of the 3/2 power law of self-thinning, because the gradient of W - $\rho$ trajectory on log-log coordinates approximated to -3/2 at the final stage of stand development. On the basis of the results of Y-N curves and W - $\rho$ trajectory, the time trajectory of maximum stem volume $W_{max obs}$ and $\rho$ was derived theoretically. The gradient of $W_{max obs}$ - $\rho$ trajectory on log-log coordinates is calculated to be -0.6105 at the final stage. The gradient of $W_{max obs}$ - $\rho$ trajectory was steeper than that of W - $\rho$ trajectory at the early stage, while the former is gentler than the latter at the later stage.stage.e.age.e.