• Title/Summary/Keyword: smooth

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AN INVERSE PROBLEM OF THE THREE-DIMENSIONAL WAVE EQUATION FOR A GENERAL ANNULAR VIBRATING MEMBRANE WITH PIECEWISE SMOOTH BOUNDARY CONDITIONS

  • Zayed, E.M.E.
    • Journal of applied mathematics & informatics
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    • v.12 no.1_2
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    • pp.81-105
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    • 2003
  • This paper deals with the very interesting problem about the influence of piecewise smooth boundary conditions on the distribution of the eigenvalues of the negative Laplacian in R$^3$. The asymptotic expansion of the trace of the wave operator (equation omitted) for small |t| and i=√-1, where (equation omitted) are the eigenvalues of the negative Laplacian (equation omitted) in the (x$^1$, x$^2$, x$^3$)-space, is studied for an annular vibrating membrane $\Omega$ in R$^3$together with its smooth inner boundary surface S$_1$and its smooth outer boundary surface S$_2$. In the present paper, a finite number of Dirichlet, Neumann and Robin boundary conditions on the piecewise smooth components (equation omitted)(i = 1,...,m) of S$_1$and on the piecewise smooth components (equation omitted)(i = m +1,...,n) of S$_2$such that S$_1$= (equation omitted) and S$_2$= (equation omitted) are considered. The basic problem is to extract information on the geometry of the annular vibrating membrane $\Omega$ from complete knowledge of its eigenvalues by analysing the asymptotic expansions of the spectral function (equation omitted) for small |t|.

Study on the Precise Controlling of Fracture Plane in Smooth Blasting Method (SB발파에서 파단면 제어의 고도화에 관한 연구)

  • Cho, Sang-Ho;Jeong, Yun-Young;Kim, Kwang-Yum;Kaneko, Katsuhiko
    • Tunnel and Underground Space
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    • v.19 no.4
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    • pp.366-372
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    • 2009
  • Recently, in order to achieve smooth fracture plane and minimize the excavation damage zone in rock blasting, controlled blasting methods which utilize new technologies such as electronic delay detonator (EDD) and a notched charge hole have been suggested. In this study, smooth blastings utilizing three wing type notched charge holes are simulated to investigate the influence of explosive initial density on the resultant fracture plane and damage zone using dynamic fracture process analysis (DFPA) code. Finally, based on the dynamic fracture process analyses, novel smooth blasting method, ED-Notch SB (Electronic Detonator Notched Charge Hole Smooth Blasting) is suggested.

Bronchodilator Effect of Higenamine in Isolated Guinea-pig Tracheal Smooth Muscle (Higenamine의 Guinea pig 기관 평활근 이완작용)

  • Yun, Hyo-in;Chang, Ki-chorl;Hong, Seong-geun;Lee, Chang-eop
    • Korean Journal of Veterinary Research
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    • v.27 no.1
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    • pp.35-40
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    • 1987
  • Higenamine, a benzyltetrahydroisopuinoline analog isolated from aconite tuber, has potent isotropic action. Recent studies suggest it may have beta receptor agonistic property in that its inotropic action is blocked by propranolol in isolated rabbit heart. However, no study has been carried out on other organs than heart. Higenamine is expected to have pharmacological actions on smooth muscle on the ground that it has catecholamine moiety and tetrahydrosioquinoline nucleus in its chemical structure, both of which are well known to have smooth muscle relaxation effects. Therefore present study was aimed at determining whether higenamine has bronchodilating effect in isolated guinea pig trachea smooth muscle rich in adrenergic beta receptor and if any, it has agonistic effect on beta receptor. The results were summarized as follows : 1. Higenamine had remarkable bronchodilating effect in guinea pig tracheal smooth muscle in a dose-dependent manner. 2. Bronchodilator effect of higenamine in isolated guinea pig tracheal smooth muscle was blocked competitively by propranolol. The $pD_2$ value of higenamine in isolated guinea pig tracheal smooth muscle was 5.65 and the $pA_2$ value of propranolol against higenamine in the same preparation was 7.97.

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The Effects of Gamimahwangtang(加味麻黃湯) extract on the Contraction of Isolated Rat Tracheal Smooth Muscle (가미마황탕(加味麻黃湯)이 흰쥐의 기관지(氣管支) 평활근(平滑筋) 수축성(收縮性)에 미치는 영향(影響))

  • Tak, Eui Soo;Kang, Yoon Ho
    • The Journal of Dong Guk Oriental Medicine
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    • v.4
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    • pp.211-236
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    • 1995
  • This study was carried out to investigate the effects of Mahwangtang and Gamimahwangtang extract and its constituent herbs on the contractile force of rat tracheal smooth muscle treated with acetylcholine and to elucidate its mechanism. The results of this study were follows ; 1. Mahwangtang and Gamimahwangtang significantly inhibited the contractile response of isolated rat tracheal smooth muscle by acetylcholine, and Gamimahwangtang more significantly effects than Mahwangtang. 2. Gamimahwangtang without Ephedrae Herba significantly inhibited the contractile response of isolated rat tracheal smooth muscle by acetylcholine and less inhibited the contractile force than Gamimahwangtang. 3. Gamimahwangtang without Fritillariae Roylei Bulbus, Platycodi Radix, Cinnamomi Ramulus, significantly inhibited the contractile response of isolated rat tracheal smooth muscle by acetylcholine and less inhibited the contractile force than Gamimahwangtang. 4. Gamimahwangtang without Armeniacae Amarum Semen, Glycyrrhizae Radix significantly inhibited the contractile response of isolated rat tracheal smooth muscle by acetylcholine and its difference did not to the Gamimahwangtang. 5. Gamimahwangtang without Ginseng Radix significantly inhibited the contractile response of isolated rat tracheal smooth muscle by acetylcholine and more significantly effects than Gamimahwangtang.

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TESTING FOR SMOOTH TRANSITION NONLINEARITY IN PARTIALLY NONSTATIONARY VECTOR AUTOREGRESSIONS

  • Seo, Byeong-Seon
    • Journal of the Korean Statistical Society
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    • v.36 no.2
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    • pp.257-274
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    • 2007
  • This paper considers the tests for the presence of smooth transition non-linearity in the partially nonstationary vector autoregressive model. The transition parameters cannot be identified under the null hypothesis of linearity, and therefore this paper develops the tests for smooth transition nonlinearity, the associated asymptotic theory and the bootstrap inference. The Monte Carlo simulation evidence shows that the bootstrap inference generates moderate size and power performances.

MULTIPLE PERIODIC SOLUTIONS FOR EIGENVALUE PROBLEMS WITH A p-LAPLACIAN AND NON-SMOOTH POTENTIAL

  • Zhang, Guoqing;Liu, Sanyang
    • Bulletin of the Korean Mathematical Society
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    • v.48 no.1
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    • pp.213-221
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    • 2011
  • In this paper, we establish a multiple critical points theorem for a one-parameter family of non-smooth functionals. The obtained result is then exploited to prove a multiplicity result for a class of periodic eigenvalue problems driven by the p-Laplacian and with a non-smooth potential. Under suitable assumptions, we locate an open subinterval of the eigenvalue.

A Study on the Mobilization of Calcium by Ginseng Alcohol Extract in Rabbit Vascular Smooth Muscle (가토 대동맥 평활근에서 인삼 알콜 추출물에 의한 Calcium 동원에 관한 연구)

  • Kim, Yong-Bae;Lee, Young-Ho;Kang, Bok-Soon;Kang, Doo-Hee
    • The Korean Journal of Physiology
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    • v.24 no.1
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    • pp.77-90
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    • 1990
  • There have been conflicting reports concerning the effect of Panax ginseng on the contractility of vascular smooth muscle, i.e., Panax ginseng extract has been reported to cause relaxation, contraction or to have no effect on the tension of vascular smooth muscle. A further investigation of $Ca^{++}$ stores which supply $Ca^{++}$ for contraction of vascular smooth muscle is needed to understand the underlying mechanisms of this conflicting effect of ginseng alcohol extract (GAE). The present study was intended to examine the sources of calcium mobilized for contraction of vascular smooth muscle by GAE. Aortic ring preparations were made from the rabbit thoracic aorta and endothelial cells were removed from the ring. The contractility of the aortic ring was measured under various experimental conditions and $Ca^{++}$ flux across the membrane of aortic ring and the sarcoplasmic reticulum and mitochondria were measured with a calcium selective electrode. The result were summarized as follows; 1) At low concentration of extracellular $Ca^{++}$, GAE increased the contractility of vascular smooth muscle in dose-dependent fashion except high concentration $Ca^{++}$ (1 mM). 2) In the presence of ryanodine, GAE still increased contractility of vascular smooth muscle as much as control group, but in the presence of caffeine, GAE increased it significantly. i.e. Their effects seemed to be additive. 3) In the presence of verapamil+lanthanum, and verapamil+lanthanum+ryanodine, the contractility of the vascular smooth muscle was decreased, but a dose dependent increase in vascular tension was still demonstrated by GAE although total tension was low. 4) GAE increased $Ca^{++}$ efflux from vascular smooth muscle cells, but have no effect on $Ca^{++}$ influx. 5) GAE increased $Ca^{++}$ efflux from sarcoplasmic reticulum and mitochondria vesicles. From the above results, it may be concluded that GAE increased the release of $Ca^{++}$ from sarcoplasmic reticulum, mitochondria or other intracellular $Ca^{++}$ stores of vascular smooth muscle, but it does not increase $Ca^{++}$ influx across the plasma membrane.

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Spatial Characteristics Shown in Landscape Design -Focusing on Five Winning Design Proposals for the Seoul City Hall Plaza Design Competition (조경설계에 나타난 공간의 특성 -시청 앞 광장 현상공모 입상작을 중심으로-)

  • 김정호
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.2
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    • pp.1-11
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    • 2003
  • The purpose of this study is to investigate how five winning design proposals for the Seoul City Hall Plaza Design Competition have shown the spatial characteristics by comparing and reviewing them. Each design proposal shown different approaches that reveal the spatial characteristics. Through scrutinizing these design proposals, some similar and different aspects among them were identified. In order to examine these aspects, the winning design proposals were analysed and compared based on five categories such as design concepts, main facilities, representation of historical images, spatial connection, and event programs. Gilles Deleuze explained the spatial characteristics as striated space and smooth space. Striated space could be defined as sedentary space. It is distant vision-optical space that has dimensional, metric, and centered characteristics, whereas smooth space is defined as nomadic, close vision-haptic space that has directional and acentered characteristics. This study focused on the analysis of spatial characteristics according to smooth space and striated space. Based on the analysis of the spatial characteristics according to the smooth and striated space, some design proposals shown more characteristics of striated space while other proposals shown more characteristics of smooth space. Those design proposals that shown more characteristics of smooth space reveal flexible or changeable shape and void space, whereas the others that shown more characteristics of striated space try to suggest apparent guidelines for the future use by retaining the idea of a plaza through the concrete shape. This study, which analyzed the winning design proposals based on the spatial characteristics according to the smooth and striated space, can be used to analyze the designs and could help to develop a new methodology with a different perspective. furthermore, it could provide practical and creative design strategies for landscape design.

Smooth Muscle Relaxation by the Herbal Medicine Ssanghwatang associated with Nitric Oxide Synthase Activation and Nitric Oxide Production

  • Kim, Joong-Kil;Shim, Ha-Na;Lee, Seung-Hee;Yoo, Kwan-Suk;Song, Bong-Keun
    • The Journal of Korean Medicine
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    • v.27 no.4
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    • pp.74-83
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    • 2006
  • Ssanghwatang (SHT) has been known to prove effective in the treatment for erectile dysfunction (ED), and its modified formula is widely used in clinical practice. However, its fundamental mechanism of action is not clearly known. It is well known that endothelial cells can achieve the relaxation of vascular smooth muscles by the release of nitric oxide (NO). NO is synthesized by the enzyme NO synthase (NOS) from L-arginine and oxygen. It is widely accepted that NO plays an important role in the relaxation of corpus cavernous smooth muscle and vasculature. In addition, in terms of the penile erection, the NO/cGMP pathway is more potent than the PCE1/cAMP pathway. The main purpose of the present study was to investigate the mechanism of the erectile effects of SHT by focusing on its direct effects on corpus cavernous smooth muscle cells. We investigated the NOS activity, nitrite concentration and cGMP levels in rat corpus cavernous smooth muscle cell lines activated by SHT extracts. Furthermore, we evaluated the effect of SHT extracts on penile smooth muscle relaxation following oral administration of SHT extract powder to rats by the dosage of 1 g/kg over fifteen days. As a result, we found that SHT stimulated NO release. NOS activity and cGMP levels were increased by SHT respectively. Furthermore, SHT relaxed the corpus cavernous smooth muscle. These results are consistent with the concept that penile erection by SHT is carried out through the NO/cGMP pathway. In conclusion, the present study shows that SHT increases the NOS activity, synthesizes NO and augments the cGMP, which mediates penile erection. Further determination of the SHT mechanism related with the NO/cGMP pathway strongly indicates that SHT can be used as a remedy for erectile impotence.

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