• Title/Summary/Keyword: smooth function

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SOLUTION TO ${\bar{\partial}}$-PROBLEM WITH SUPPORT CONDITIONS IN WEAKLY q-CONVEX DOMAINS

  • Saber, Sayed
    • Communications of the Korean Mathematical Society
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    • v.33 no.2
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    • pp.409-421
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    • 2018
  • Let X be a complex manifold of dimension n $n{\geqslant}2$ and let ${\Omega}{\Subset}X$ be a weakly q-convex domain with smooth boundary. Assume that E is a holomorphic line bundle over X and $E^{{\otimes}m}$ is the m-times tensor product of E for positive integer m. If there exists a strongly plurisubharmonic function on a neighborhood of $b{\Omega}$, then we solve the ${\bar{\partial}}$-problem with support condition in ${\Omega}$ for forms of type (r, s), $s{\geqslant}q$ with values in $E^{{\otimes}m}$. Moreover, the solvability of the ${\bar{\partial}}_b$-problem on boundaries of weakly q-convex domains with smooth boundary in $K{\ddot{a}}hler$ manifolds are given. Furthermore, we shall establish an extension theorem for the ${\bar{\partial}}_b$-closed forms.

Airway Remodelling in Asthma (기관지 천식에서의 기도 개형)

  • Lim, Dae Hyun
    • Clinical and Experimental Pediatrics
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    • v.48 no.10
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    • pp.1038-1049
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    • 2005
  • Asthma is characterized by a chronic inflammatory disorder of the airways that leads to tissue injury and subsequent structural changes collectively called airway remodelling. Characteristic changes of airway remodelling in asthma include goblet cell hyperplasia, deposition of collagens in the basement membrane, increased number and size of microvessels, hypertrophy and hyperplasia of airway smooth muscle, and hypertrophy of submucosal glands. Apart from inflammatory cells, such as eosinophils, activated T cells, mast cells and macrophages, structural tissue cells such as epithelial cells, fibroblasts and smooth muscle cells can also play an important effector role through the release of a variety of mediators, cytokines, chemokines, and growth factors. Through a variety of inflammatory mediators, epithelial and mesenchymal cells cause persistence of the inflammatory infiltrate and induce airway structural remodelling. The end result of chronic airway inflammation and remodelling is an increased thickness of the airway wall, leading to a increased the bronchial hyperresponsiveness and fixed declined lung function.

Automatic Feedrate Adjustment for 2D Profile Milling (2차원 윤곽가공에서 이송률 자동 조정)

  • 고기훈;서정철;최병규
    • Korean Journal of Computational Design and Engineering
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    • v.5 no.2
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    • pp.175-183
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    • 2000
  • Proposed in this paper is a model-bated AFA (automatic feedrate-adjustment) method for maintaining smooth cutting-loads (i.e., cutting-force) during 2D-profile milling. Before the cutting-force model was established, some assumptions were verified through a series of preliminary cutting experiments (The results found that the curving-force was independent of the cutting speed and the cutting action at the cutter bosom). From the data obtained during the main cutting experiments, a “chip-load/cutting-force model”representing the cutting-force as a function of the chip-load (i.e., effective cutting-depth) and a feedrate is proposed. Based on the model. an AFA scheme for maintaining smooth cutting-force by adjusting the feedrate (i.e., F-code) according to the changes in chip-load was proposed. To check the validity of the proposed AFA scheme. another set of cutting experiments was conducted by using feedrate-adjusted NC-data while monitoring the actual machining processes using an accelerometer. The experimental results showed that the proposed AFA-scheme was quite effective.

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BOUNDARY BEHAVIOR OF LARGE SOLUTIONS FOR QUASILINEAR ELLIPTIC EQUATIONS

  • Sun, Juan;Yang, Zuodong
    • Journal of applied mathematics & informatics
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    • v.29 no.3_4
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    • pp.969-980
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    • 2011
  • In this paper, our main purpose is to consider the quasilinear elliptic equation $$div(|{\nabla}u|^{p-2}{\nabla}u)=(p-1)f(u)$$ on a bounded smooth domain ${\Omega}\;{\subset}\;R^N$, where p > 1, N > 1 and f is a smooth, increasing function in [0, ${\infty}$). We get some estimates of a solution u satisfying $u(x){\rightarrow}{\infty}$ as $d(x,\;{\partial}{\Omega}){\rightarrow}0$ under different conditions on f.

A Data Hiding Scheme for Grayscale Images Using a Square Function

  • Kwon, Hyejin;Kim, Haemun;Kim, Soonja
    • Journal of Korea Multimedia Society
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    • v.17 no.4
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    • pp.466-477
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    • 2014
  • Many image hiding schemes based on least significant bit (LSB) transformation have been proposed. One of the LSB-based image hiding schemes that employs diamond encoding was proposed in 2008. In this scheme, the binary secret data is converted into base n representation, and the converted secret data is concealed in the cover image. Here, we show that this scheme has two vulnerabilities: noticeable spots in the stego-image, i.e., a non-smooth embedding result, and inefficiency caused by rough re-adjustment of falling-off-boundary value and impractical base translation. Moreover, we propose a new scheme that is efficient and produces a smooth and high quality embedding result by restricting n to power of 2 and using a sophisticated re-adjustment procedure. Our experimental results show that our scheme yields high quality stego-images and is secure against RS detection attack.

Bearing capacity of foundation on rock mass depending on footing shape and interface roughness

  • Alencar, Ana S.;Galindo, Ruben A.;Melentijevic, Svetlana
    • Geomechanics and Engineering
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    • v.18 no.4
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    • pp.391-406
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    • 2019
  • The aim of this paper was to study the influence of the footing shape and the effect of the roughness of the foundation base on the bearing capacity of shallow foundations on rock masses. For this purpose the finite difference method was used to analyze the bearing capacity of various types and states of rock masses under the assumption of Hoek-Brown failure criterion, for both plane strain and axisymmetric model, and considering smooth and rough interface. The results were analyzed based on a sensitivity study of four varying parameters: foundation width, rock material constant (mo), uniaxial compressive strength and geological strength index. Knowing how each parameter influences the bearing capacity depending on the footing shape (circular vs strip footing) and the footing base interface roughness (smooth vs rough), two correlation factors were developed to estimate the percentage increase of the ultimate bearing capacity as a function of the footing shape and the roughness of the footing base interface.

A VANISHING THEOREM FOR REDUCIBLE SPACE CURVES AND THE CONSTRUCTION OF SMOOTH SPACE CURVES IN THE RANGE C

  • Ballico, Edoardo
    • Communications of the Korean Mathematical Society
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    • v.34 no.1
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    • pp.105-111
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    • 2019
  • Let $Y{\subset}{\mathbb{P}}^3$ be a degree d reduced curve with only planar singularities. We prove that $h^i({\mathcal{I}}_Y(t))=0$, i = 1, 2, for all $t{\geq}d-2$. We use this result and linkage to construct some triples (d, g, s), $d>s^2$, with very large g for which there is a smooth and connected curve of degree d and genus g, $h^0({\mathcal{I}}_C(s))=1$ and describe the Hartshorne-Rao module of C.

Role of $Na^+/Ca^{2+}$ Exchange in the Control of Contractility in Rabbit Basilar Arterial Smooth Muscle

  • Kim, Eui-Yong;Han, Jin
    • The Korean Journal of Physiology
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    • v.28 no.2
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    • pp.159-167
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    • 1994
  • The contraction of rabbit basilar artery was examined as a function of changes in the $Na^+$ electrochemical gradient in order to determine the contribution of $Na^+/Ca^{2+}$ exchange to the modulation of contractility. Ouabain $(10^{-5}\;M)$ or $K^+-free$ Tyrode solution caused an increase in tonic tension even in the presence of a $Ca^{2+}$ channel blocker $(10^{-6}\;M\;verapamil)$ and an ${\alpha}-receptor$ blocker $(10^{-5}\;M\;phentolamine)$. After treatment with ouabain $(10^{-5}\;M)$, contractions were augmented by reduction of external $Na^+$ concentration. The longer the treatment with ouabain $(10^{-5}\;M)$ was, the larger the amplitude of $Na^+-free$ contracture was. $Na^+-free$ contracture wag induced by either substitution of equimolar Tris for $Na^+$ or substitution of equimolar $Li^+\;for\;Na^+$. The competition between $Na^+\;and\;Ca^{2+}$ for the $Na^+/Ca^{2+}$ exchange carrier would exist, because it was observed that contractility was dependent on the $Na^+$ electrochemical gradient or the extracellular $Ca^{2+}$ concentration (2 mM, 4 mM). Ryanodine $(10^{-7}\;M)$, the blocker of intracellular $Ca^{2+}$ release from the sarcoplasmic reticulum, did not suppress the development of $Na^+-free$ contracture. The contractile response to norepinephrine $(10^{-6}\;M)$ was augmented by reducing the extracellular $Na^+$ concentration. The relaxation rate from caffeine-induced contraction was dependent on the extracellular $Na^+$ concentration (0 mM, 140 mM). From the above results, it could be suggested that $Na^+/Ca^{2+}$ exchange can move $Ca^{2+}$ either into or out of rabbit basilar arterial smooth muscle. $Ca^{2+}$ entry or extrusion is dependent upon the $Na^+$ electrochemical gradient. $Na^+/Ca^{2+}$ exchange plays a significant role in the regulation of contractility in rabbit basilar arterial smooth muscle.

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The Effects of Smooth Pursuit Eye Movement and Saccadic Eye Movement on Balance and Muscle Activation during One Leg Standing (한 다리 서기 동안 매끈눈따라보기와 신속눈운동이 균형과 근활성도에 미치는 영향)

  • Young-Bum, Jung;Gyu-Ryeong, Kim;Myoung-Kwon, Kim
    • Journal of the Korean Society of Physical Medicine
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    • v.17 no.4
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    • pp.113-121
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    • 2022
  • PURPOSE: This study is examined the effects of vestibular stimulation through eye movement on balance and muscle activity. METHODS: In 42 healthy adults, no eye exercise was applied to both feet and one foot. The speed of smooth pursuit eye movement (.2 Hz, .3 Hz, and .5 Hz) and saccadic eye movement (.5 Hz and 1.1 Hz) were randomized. The measurements were taken three times for 30 seconds while standing on two feet and measured three times for 10 seconds while standing on one foot. The muscle activity measurement equipment was used to measure the electromyogram signals of the tibialis anterior, peroneus longus, gastrocnemius medialis, vastus medialis, vastus lateralis, biceps femoris, abdominal internal oblique, and erector spinae muscle. RESULTS: As a result of this study, when applying smooth pursuit eye movement on one leg, the pressure center movement increased, the muscle activity of the lower extremity increased, in the saccadic eye movement, and the center of pressure decreased. CONCLUSION: Accordingly, the smooth pursuit of eye movement, the intervention of this study, affects balance. Through this, the balance can be improved by applying eye movement to the target who needs to improve the balance ability.

Test for Discontinuities in Nonparametric Regression

  • Park, Dong-Ryeon
    • Communications for Statistical Applications and Methods
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    • v.15 no.5
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    • pp.709-717
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    • 2008
  • The difference of two one-sided kernel estimators is usually used to detect the location of the discontinuity points of regression function. The large absolute value of the statistic imply discontinuity of regression function, so we may use the difference of two one-sided kernel estimators as the test statistic for testing null hypothesis of a smooth regression function. The problem is, however, we only know the asymptotic distribution of the test statistic under $H_0$ and we hardly expect the good performance of test if we rely solely on the asymptotic distribution for determining the critical points. In this paper, we show that if we adjust the bias of test statistic properly, the asymptotic rules hold for even small sample size situation.