• Title/Summary/Keyword: ${\tau}_m$

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Evaluation of three-dimensional cole-cole parameters from spectral IP data

  • Yang Jeong-Seok;Kim Hee Joon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.383-389
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    • 2003
  • Clay minerals show a distinct induced-polarization phenomenon, which is one of the most important factors for predicting groundwater flow and contaminant transport. This paper presents a step-by-step process to estimate Cole-Cole parameters from spectral induced-polarization (IP) data measured on the surface of three-dimensional earth. First, the inversion of low-frequency resistivity survey data is made to identify the dc resistivity ${\rho}_dc$ of a volume having IP effects. The other parameters, chargeability m, time constant $\tau$, and frequency dependence c, are sought for the polarizable volume. Next, using multi-frequency data, c can be obtained as high or low asymptotes of the slope of log phase vs. log frequency. Further, for low m, intrinsic $\tau$ is approximated by apparent one, ${\tau}_a$, which is derived from the relation ${{\omega}{\tau}}_a$=1 at an angular frequency $\omega$, where the imaginary component of spectral IP data has an extreme value. Finally, to obtain intrinsic m a two-step linearized procedure has been derived. For a body of given $\tau$ and c, forward modeling with a progression of m values yields a plot of observed vs. intrinsic imaginary components for a frequency. Since this plot is essentially linear, to extract the intrinsic imaginary component is quite simple with an observed value. Using the plot of intrinsic imaginary component vs. m, intrinsic m is determined. We present a synthetic example to illustrate that the Cole-Cole parameters can be recovered from spectral IP data.

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TWISTED HOPF COMODULE ALGEBRAS (2)

  • Park, Jun Seok
    • Journal of the Chungcheong Mathematical Society
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    • v.14 no.1
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    • pp.85-103
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    • 2001
  • Suppose that Hand K are paired Hopf algebras and that A is an H - K - bicomodule algebra with multiplication which is a left H-comodule map and is a right K-comodule map. We define a new twisted algebra, $A^{\tau}$ and define $M^{\tau}$ for $M{\in}M_A^K$. We find an equivalent condition for $M^{\tau}{\in}M_{A^{\tau}}^K$. We show that the above defined twisted multiplication is the special case of Beattie's twist multiplication. We show that if K is commutative, then A is an H-module algebra and show that if $H^*$ is cocommutative then the construction of smash product appears as a special case of the new twist product.

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Measurement of the coherence time of the light from a quasi-thermal source (준열광원의 결맞음시간 측정)

  • Kim, Hyun-Oh;Ha, Yang;Shin, Jong-Tae;Kim, Tae-Soo
    • Korean Journal of Optics and Photonics
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    • v.7 no.4
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    • pp.341-347
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    • 1996
  • The photocount distribution from a quasi-thermal light source, a moving ground glass disk (surface roughness; 9 ${\mu}{\textrm}{m}$) illuminated by a well-stabilized He-Ne laser, is measured by a photon counting system, and analyzed with theoretical calculations. The distribution approaches the Poisson distribution for the long coherence time ${\tau}_c$ compared to the measuring time T. The coherence time ${\tau}_c$ of the quasi-thermal source can be changed by controlling the velocity v of the motor driving the glass disk. By the comparison of experimental results and theory for the condition of T/ ${\tau}_c$ >>1, the coherence time ${\tau}_c$ of the quasi-thermal source is turned out to be in the range of 31.43 $mutextrm{s}$~2.48 $mutextrm{s}$ according to the circumferential velocity of the disk, and compared with the simple calculation of $\sigma$/v.

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Mobility Management of M2M Devices with Grouping in the LTE System (LTE 시스템에서 그룹 기반 M2M 단말 이동성 관리)

  • Roh, Hee-Tae;Lee, Jang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.12
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    • pp.1119-1127
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    • 2012
  • The one of features of M2M communications, which are recently attracted attention as a future business of mobile communications, is that there is a large number of devices compared with traditional communication services. Hence, the control signal that are generated by the M2M devices may cause a significant congestion in the network and in order to solve this problem, a standardization is progressing for reducing the redundant signaling by managing M2M devices as a group in 3GPP standardization. In this paper, we propose a method of group based mobility management by managing M2M devices that have the same mobility as a group. In the proposed method, M2M devices that have the same mobility are grouped by the Mobility Management Entity (MME) and the MME elects a group header among the M2M devices in the group. Then, the group header performs the Tracking Area Update (TAU) on behalf of the group members to reduce the signaling overhead of mobility management. With the proposed method, we can achieve 80% decrease of the signaling overhead of mobility management compared with the case where each M2M device individually performs its TAU procedure.

Comparison of an Analytic Solution of Wind-driven Current and all (x-$\sigma$) Numerical Model (취송류의 해석위와 (x-$\sigma$) 수치모형과의 비교)

  • 이종찬;최병호
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.4 no.4
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    • pp.208-218
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    • 1992
  • Analytic solutions for the gradient of surface elevation and vertical profiles of velocity driven by the wind stress in the one-dimensional rectangular basin were obtained under the assumption of steady-state. The approach treats the bottom frictional stress $\tau$$_{b}$ as known and includes vertically varying eddy viscosity $textsc{k}$$_{M}$, which is constant, linear and quadratic of water depth. When the $\tau$$_{b}$ is param-terized with surface stress, depth averaged velocity and bottom velocity, the result shows the relation of the no-slip bottom velocity condition and the bottom frictional stress $\tau$$_{b}$. The results of a mode splitted, (x-$\sigma$) coordinate, numerical model were compared with the derived analytic solutions. The comparison was made for the case such that $textsc{k}$$_{M}$ is the constant, linear and quadratic function of water depth. In the case of constant $textsc{k}$$_{M}$, the gradient of surface elevation and vertical profiles of velocity are discussed for a uniform depth, a mild slope and a relatively steep slope. When $textsc{k}$$_{M}$ is a linear and quadratic function of water depth, the vertical structures of velocities are discussed for various $\tau$$_{b}$. The result of the comparison shows that the vertical structure of velocities depends not only on the value of $textsc{k}$$_{M}$ but also on the profile of $textsc{k}$$_{M}$ and bottom stress $\tau$$_{b}$. Model results were in a good agreement with the analytic solutions considered in this study.his study.y.his study.

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Tau mis-splicing in the pathogenesis of neurodegenerative disorders

  • Park, Sun Ah;Ahn, Sang Il;Gallo, Jean-Marc
    • BMB Reports
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    • v.49 no.8
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    • pp.405-413
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    • 2016
  • Tau proteins, which stabilize the structure and regulate the dynamics of microtubules, also play important roles in axonal transport and signal transduction. Tau proteins are missorted, aggregated, and found as tau inclusions under many pathological conditions associated with neurodegenerative disorders, which are collectively known as tauopathies. In the adult human brain, tau protein can be expressed in six isoforms due to alternative splicing. The aberrant splicing of tau pre-mRNA has been consistently identified in a variety of tauopathies but is not restricted to these types of disorders as it is also present in patients with non-tau proteinopathies and RNAopathies. Tau mis-splicing results in isoform-specific impairments in normal physiological function and enhanced recruitment of excessive tau isoforms into the pathological process. A variety of factors are involved in the complex set of mechanisms underlying tau mis-splicing, but variation in the cis-element, methylation of the MAPT gene, genetic polymorphisms, the quantity and activity of spliceosomal proteins, and the patency of other RNA-binding proteins, are related to aberrant splicing. Currently, there is a lack of appropriate therapeutic strategies aimed at correcting the tau mis-splicing process in patients with neurodegenerative disorders. Thus, a more comprehensive understanding of the relationship between tau mis-splicing and neurodegenerative disorders will aid in the development of efficient therapeutic strategies for patients with a tauopathy or other, related neurodegenerative disorders.

ON GENERALIZED LIE IDEALS IN SEMI-PRIME RINGS WITH DERIVATION

  • Ozturk, M. Ali;Ceven, Yilmaz
    • East Asian mathematical journal
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    • v.21 no.1
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    • pp.1-7
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    • 2005
  • The object of this paper is to study($\sigma,\;\tau$)-Lie ideals in semi-prime rings with derivation. Main result is the following theorem: Let R be a semi-prime ring with 2-torsion free, $\sigma$ and $\tau$ two automorphisms of R such that $\sigma\tau=\tau\sigma$=, U be both a non-zero ($\sigma,\;\tau$)-Lie ideal and subring of R. If $d^2(U)=0$, then d(U)=0 where d a non-zero derivation of R such that $d\sigma={\sigma}d,\;d\tau={\tau}d$.

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Neural Transdifferentiation: MAPTau Gene Expression in Breast Cancer Cells

  • Lara-Padilla, E;Miliar-Garcia, A;Gomez-Lopez, M;Romero-Morelos, P;Bazan-Mendez, CI;Alfaro-Rodriguez, A;Anaya-Ruiz, M;Callender, K;Carlos, A;Bandala, C
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1967-1971
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    • 2016
  • Background: In tumor cells, aberrant differentiation programs have been described. Several neuronal proteins have been found associated with morphological neuronal-glial changes in breast cancer (BCa). These neuronal proteins have been related to mechanisms that are involved in carcinogenesis; however, this regulation is not well understood. Microtubule-associated protein-tau (MAP-Tau) has been describing in BCa but not its variants. This finding could partly explain the neuronal-glial morphology of BCa cells. Our aim was to determine mRNA expression of MAP-tau variants 2, 4 and 6 in breast cancer cell lines. Materials and Methods: Cultured cell lines MCF-10A, MDA-MB-231, SKBR3 and T47D were observed under phase-contrast microscopy for neural morphology and analyzed for gene expression of MAP-Tau transcript variants 2, 4 and 6 by real-time PCR. Results: Regarding morphology like neural/glial cells, T47D line shown more cells with these features than MDA-MB-231 and SKBR. In another hand, we found much greater mRNA expression of MAP-Tau transcript variants 2, and to a lesser extent 4 and 6, in T47D cells than the other lines. In conclusion, regulation of MAP-Tau could bring about changes in cytoskeleton, cell morphology and motility; these findings cast further light on neuronal transdifferentiation in BCa.

τ-CENTRALIZERS AND GENERALIZED DERIVATIONS

  • Zhou, Jiren
    • Journal of the Korean Mathematical Society
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    • v.47 no.3
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    • pp.523-535
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    • 2010
  • In this paper, we show that Jordan $\tau$-centralizers and local $\tau$-centralizers are $\tau$-centralizers under certain conditions. We also discuss a new type of generalized derivations associated with Hochschild 2-cocycles and introduce a special local generalized derivation associated with Hochschild 2-cocycles. We prove that if $\cal{L}$ is a CDCSL and $\cal{M}$ is a dual normal unital Banach $alg\cal{L}$-bimodule, then every local generalized derivation of above type from $alg\cal{L}$ into $\cal{M}$ is a generalized derivation.

On a Class of γ*-pre-open Sets in Topological Spaces

  • Krishnan, G. Sai Sundara;Saravanakumar, D.;Ganster, M.;Ganster, M.
    • Kyungpook Mathematical Journal
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    • v.54 no.2
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    • pp.173-188
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    • 2014
  • In this paper, a new class of open sets, namely ${\gamma}^*$-pre-open sets was introduced and its basic properties were studied. Moreover a new type of topology ${\tau}_{{\gamma}p^*}$ was generated using ${\gamma}^*$-pre-open sets and characterized the resultant topological space (X, ${\tau}_{{\gamma}p^*}$) as ${\gamma}^*$-pre-$T_{\frac{1}{2}}$ space.