• Title/Summary/Keyword: sharp estimate

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Estimation of the Interface of Seawater Intrusion in a Coastal Aquifer System with SHARP Model (SHARP 모델을 이용한 해안 대수층의 해수침투 경계면 추정)

  • 심병완;정상용
    • Journal of Soil and Groundwater Environment
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    • v.8 no.1
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    • pp.68-74
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    • 2003
  • SHARP numerical model was used to estimate the interface, ranges and seasonal variations of seawater intrusion. The interface obtained from the SHARP model represented more sensitive to seasonal variations than that estimated from the monitoring wells. When TDS and groundwater velocity vector distributions generated by SUTRA simulations are compared to the interfaces obtained from SHARP simulation, the difference of the range on seawater intrusion is less than 50 m, and the range of seawater intrusion from seasonal variations has the difference of about 12 m. These differences are small for the numerical simulation of the coastal aquifer at regional scale. Therefore, the model with sharp interface is very useful to estimate the interface at this study site, where is regional aquifer system in the scale of seawater infusion. However the SHARP model have some limitations in simulating the range of seawater intrusion, when the hydrodynamic dispersion is significant for seawater intrusion at local aquifer system.

SHARP COEFFICIENT INEQUALITIES FOR CERTAIN SUBCLASSES OF BI-UNIVALENT BAZILEVIČ FUNCTIONS

  • Patil, Amol Bhausaheb
    • Communications of the Korean Mathematical Society
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    • v.37 no.1
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    • pp.113-123
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    • 2022
  • In the present paper, we introduce the subclasses 𝔅(𝜇), B(𝜇, 𝛾) and UΣ(𝜇, 𝛾) of bi-univalent Bazilevič functions which are defined in the open unit disk 𝔻. Further, we obtain sharp estimates on initial coefficients a2, a3, a4 and also sharp estimate on the Fekete-Szegö functional a3 - ka22 for the functions belong to these subclasses.

SHARP FUNCTION AND WEIGHTED $L^p$ ESTIMATE FOR PSEUDO DIFFERENTIAL OPERATORS WITH REDUCED SYMBOLS

  • Kim, H.S.;Shin, S.S.
    • East Asian mathematical journal
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    • v.6 no.2
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    • pp.133-144
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    • 1990
  • In 1982, N. Miller [5] showed a weighted $L^p$ boundedness theorem for pseudo differential operators with symbols $S^0_{1.0}$. In this paper, we shall prove the pointwise estimates, in terms of the Fefferman, Stein sharp function and Hardy Littlewood maximal function, for pseudo differential operators with reduced symbols and show a weighted $L^p$-boundedness for pseudo differential operators with symbol in $S^m_{\rho,\delta}$, 0{$\leq}{\delta}{\leq}{\rho}{\leq}1$, ${\delta}{\neq}1$, ${\rho}{\neq}0$ and $m=(n+1)(\rho-1)$.

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MIXED RADIAL-ANGULAR INTEGRABILITIES FOR HARDY TYPE OPERATORS

  • Ronghui Liu ;Shuangping Tao
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.5
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    • pp.1409-1425
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    • 2023
  • In this paper, we are devoted to studying the mixed radial-angular integrabilities for Hardy type operators. As an application, the upper and lower bounds are obtained for the fractional Hardy operator. In addition, we also establish the sharp weak-type estimate for the fractional Hardy operator.

Problems Occurred with Histogram and a Resolution

  • Park, Byeong Uk;Park, Hong Nae;Song, Moon Sup;Song, Jae Kee
    • Journal of Korean Society for Quality Management
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    • v.18 no.2
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    • pp.127-133
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    • 1990
  • In this article, several problems inherent in histogram estimate of unknown probability density function are discussed. Those include so called sharp comers and bin edge effect. A resolution for these problems occurred with histogram is discussed. The resulting estimate is called kernel density estimate which is most widely used by data analysts. One of the most recent and reliable data-based choices of scale factor (bandwidth) of the estimate, which has been known to be most crucial, is also discussed.

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SHARP BOUNDS FOR INITIAL COEFFICIENTS AND THE SECOND HANKEL DETERMINANT

  • Ali, Rosihan M.;Lee, See Keong;Obradovic, Milutin
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.4
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    • pp.839-850
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    • 2020
  • For functions f(z) = z + a2z2 + a3z3 + ⋯ belonging to particular classes, this paper finds sharp bounds for the initial coefficients a2, a3, a4, as well as the sharp estimate for the second order Hankel determinant H2(2) = a2a4 - a23. Two classes are treated: first is the class consisting of f(z) = z + a2z2 + a3z3 + ⋯ in the unit disk 𝔻 satisfying $$\|\(\frac{z}{f(z)}\)^{1+{\alpha}}\;f^{\prime}(z)-1\|<{\lambda},\;0<{\alpha}<1,\;0<{\lambda}{\leq}1.$$ The second class consists of Bazilevič functions f(z) = z+a2z2+a3z3+⋯ in 𝔻 satisfying $$Re\{\(\frac{f(z)}{z}\)^{{\alpha}-1}\;f^{\prime}(z)\}>0,\;{\alpha}>0.$$

Toward Occlusion-Free Depth Estimation for Video Production

  • Park, Jong-Il;Seiki-Inoue
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1997.06a
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    • pp.131-136
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    • 1997
  • We present a method to estimate a dense and sharp depth map using multiple cameras for the application to flexible video production. A key issue for obtaining sharp depth map is how to overcome the harmful influence of occlusion. Thus, we first propose to selectively use the depth information from multiple cameras. With a simple sort and discard technique, we resolve the occlusion problem considerably at a slight sacrifice of noise tolerance. However, boundary overreach of more textured area to less textured area at object boundaries still remains to be solved. We observed that the amount of boundary overreach is less than half the size of the matching window and, unlike usual stereo matching, the boundary overreach with the proposed occlusion-overcoming method shows very abrupt transition. Based on these observations, we propose a hierarchical estimation scheme that attempts to reduce boundary overreach such that edges of the depth map coincide with object boundaries on the one hand, and to reduce noisy estimates due to insufficient size of matching window on the other hand. We show the hierarchical method can produce a sharp depth map for a variety of images.

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Terminal Reliability Evaluation in RBN and MANET (RBN과 MANET에서의 터미널 간 신뢰도 평가)

  • Lee Jun-Hyuk;Kim Kyung-Mok;Oh Young-Hwan
    • Journal of Applied Reliability
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    • v.6 no.2
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    • pp.187-194
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    • 2006
  • In this paper, We presented the algorithm for estimating a reliability between nodes in wireless communication network such as RBN and MANET To estimate the reliability between nodes, we first modeled RNB and MANET as probability graph. Branches of the graph are always reliable and the probability of node failure is independent. After all possible simple path which can be established between two nodes are examined, we perform sharp arithmetic to remove repetition event between two nodes. Using probability for each variable of the minimized Boolean equation, we present the reliability formula.

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