• Title/Summary/Keyword: closure function

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Surgical Management of Esophageal Perforation due to Fish Bone: A Report of Four Cases (생선뼈'에 의한 식도천공의 외과적 치료: 4례 보고)

  • 지행옥;김근호
    • Journal of Chest Surgery
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    • v.6 no.1
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    • pp.95-100
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    • 1973
  • This is a report on a total of four cases of esophageal perforation due to fish bone in the Department of Thoracic Surgery, Hanyang University Hospital. The perforated portions of esophagus were upper third of esophagus, that is, cervical esophalgus principally. The complications after esophageal perforation were acute mediastinitis with mediastinal emphysema in 2 cases, acute mediastinitis with both pyothorax in one case and cervical subcutaneous abscess alone in one case. Collar mediastinostomy was required to control disturbance of cardiopulmonary function as emergency procedure. Gastrostomy was of worthy for the various purposes, that` is, for feeding, absolute rest of the esophagus, and for prevention against continuous infection from esophageal leakage. After the gastrostomy. 3 cases were healed by spontaneous closure of esophageal perforation between one to four weeks. One case expired from severe septic shock due to acute diffuse mediastinitis and both pyothorax.

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Relations of Visual Perception and Hand Dexterity using Computer Keyboard (컴퓨터 타자속도에서 시지각 및 손 민첩성의 상관성)

  • Roh, Hyo-Lyun;Kang, Shin-Wook
    • Journal of Korean Clinical Health Science
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    • v.2 no.4
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    • pp.209-215
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    • 2014
  • Purpose. The purpose of this study was to determine the relationship between typing speed required dexterity of hand and visual perception. Method. We studied 50 people who were not experience of hand injury in K university. Typing speed, hand dexterity and visual perception were measured using purdue pegboard test, MVPT-3 and 'Cheongsando' in Hancom typing program. Results analysis was used Pearson correlation coefficient of the SPSS 10.0. Result. In this study, the typing speed showed a positive correlation with the figure ground, but there was no correlation visual closure and visual discrimination. Conclusion. Typing speed was correlated with hand dexterity and figure ground. Therefore, utilizing a computer keyboard at treatment can be expected to enhance hand function and visual perception.

INCLUSION PROPERTIES OF A CLASS OF FUNCTIONS INVOLVING THE DZIOK-SRIVASTAVA OPERATOR

  • Devi, Satwanti;Srivastava, H.M.;Swaminathan, A.
    • Korean Journal of Mathematics
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    • v.24 no.2
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    • pp.139-168
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    • 2016
  • In this work, we rst introduce a class of analytic functions involving the Dziok-Srivastava linear operator that generalizes the class of uniformly starlike functions with respect to symmetric points. We then establish the closure of certain well-known integral transforms under this analytic function class. This behaviour leads to various radius results for these integral transforms. Some of the interesting consequences of these results are outlined. Further, the lower bounds for the ratio between the functions f(z) in the class under discussion, their partial sums $f_m(z)$ and the corresponding derivative functions f'(z) and $f^{\prime}_m(z)$ are determined by using the coecient estimates.

AN ERROR ANALYSIS OF THE DISCRETE GALERKIN SCHEME FOR NONLINEAR INTEGRAL EQUATIONS

  • YOUNG-HEE KIM;MAN-SUK SONG
    • Communications of the Korean Mathematical Society
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    • v.9 no.2
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    • pp.423-438
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    • 1994
  • We employ the Galerkin method to solve the nonlinear Urysohn integral equation (1.1) x(t) = f(t) + $∫_{D}$ k(t, s, x(s))ds (t $\in$ D), where D is a bounded domain in $R^{d}$ , the function f and k are known and x is the solution to be determined. We assume that D has a locally Lipschitz boundary ([1, p. 67]). We can rewrite (1.1) in operator notation as x = f + Kx. We consider (1.1) as an operator equation on $L_{\infty$}$(D) and assume that K is defined on the closure $\Omega$ of a bounded open set $\Omega$$L_{\infty}$(D). Throughout our analysis we put the following assumptions on (1.1).(omitted)(1.1).(omitted)

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Turbulent Flow through a Square Straight and Curved Duct with Reynolds Stress Models (정사각 직관과 $180^{\circ}$ 곡관내 난류유동의 레이놀즈응력모형 적용)

  • Chun, Kun-Ho;Choi, Young-Don
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.771-776
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    • 2000
  • Fine grid calculations are reported for the developing turbulent flow in a straight duct and a curved duct of square cross-section with a radius of curvature to hydraulic diameter ratio ${\delta}=R_c/H_H=3.357$ and a bend angle of 180 deg. A sequence of modeling refinements is introduced; the replacement of wall function by a fine mesh across the sublayer and a low Reynolds number second moment closure up to the near wall sublayer in which the non-linear return to isotropy model and the cubic-quasi-isotropy model for the pressure strain are adopted; and the introduction of a multiple source model for the exact dissipation rate equation. Each refinement is shown to lead to an appreciable improvement in the agreement between measurement and computation.

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Optimization of a Wire-Spacer Fuel Assembly of Liquid Metal reactor

  • Ahmad, Imteyaz;Kim, Kwang-Yong
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.240-243
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    • 2005
  • This study deals with the shape optimization of a wire spacer fuel assembly of Liquid Metal Reactors (LMRs). The Response Surface based optimization Method is used as an optimization technique with the Reynolds-averaged Navier-Stokes analysis of fluid flow and heat transfer using Shear Stress Transport (SST) turbulence model as a turbulence closure. Two design variables namely, pitch to fuel rod diameter ratio and lead length to fuel rod diameter ratio are selected. The objective function is defined as a combination of the heat transfer rate and the inverse of friction loss with a weighting factor. Three level full-factorial method is used to determine the training points. In total, nine experiments have been performed numerically and the resulting datas have been analysed for optimization study. Also, a comparison has been made between the optimized surface and the reference one in this study.

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Design Optimization of Pin-Fin Sharp to Enhance Heat Transfer

  • Li, Ping;Kim, Kwang-Yong
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.185-190
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    • 2005
  • This work presents a numerical procedure to optimize the elliptic-shaped pin fin arrays to enhance turbulent heat transfer. The response surface method is used as an optimization technique with Reynolds-averaged Navier Stokes analysis of flow and heat transfer. Shear stress transport (SST) turbulence model is used as a turbulence closure. Computational results for average heat transfer rate show a reasonable agreement with the experimental data. Four variables including major axis length, minor axis length, pitch and the pin fin length nondimensionalized by duct height are chosen as design variables. The objective function is defined as a linear combination of heat transfer and friction-loss related terms with weighting factor. D-optimal design is used to reduce the data points, and, with only 28 points, reliable response surface is obtained. Optimum shapes of the pin-fin arrays have been obtained in the range from 0.0 to 0.1 of weighting factor.

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A Single Left Lung Transplantation in Dog -One Case Report- (황견에서 좌측 폐이식수술 -1례 보고-)

  • 이두연
    • Journal of Chest Surgery
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    • v.27 no.3
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    • pp.238-240
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    • 1994
  • We performed post-operative hemodynamic evaluation and lung perfusion scan after left lung transplantation in dog. The heart & lungs were extracted from donor dog while the both lungs were flushed with 4oC Euro-Collin`s solution after heparinization & infusion of prostaglandin E1.In the recipient dog, anastomosis of the left atrial cuff was performed by continuous 4-0 Prolene everted suture, and bronchial anastomosis by telescope method with 4-0 Prolene continuous suture. The end-to-end anastomosis of left main pulmonary arteries was performed with continuous 6-0 Prolene suture. After closure of left thoracotomy incision, the lung perfusion scan was performed post operative 2 days for evaluation of the function of the transplanted lung which showed good perfusion. The dog was sacrificed in the post-operative 5 days for autopsy.

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Retroperitoneal Approach for the Surgical Treatment of Abdominal Aortic Aneurysm; One Case Report (복막후방접근방법을 이용한 상복부 대동맥류의 외과적 치료;1례 보고)

  • 홍순필
    • Journal of Chest Surgery
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    • v.26 no.6
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    • pp.492-495
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    • 1993
  • We experienced one case of surgical treatment of abdominal aortic aneurysm using retroperitoneal approach. The transperitoneal route has been the standard surgical approach for elective and emergency treatment of aneurysmal or occlusive disease. Among its cited advantages for aortic reconstruction are familarity with the exposure, easy access to the infrarenal aorta and iliac vessels, possibility of simultaneous inspection of the intra-abdominal viscera, and speed of opening and closure.Despite the proved versatility of the transperitoneal approach, it is commonly associated with prolonged ileus, increased third space fluid loss, and significant pulmonary complications. The retroperitoneal approach, on the other hand, has many advantages; excellent exposure for the repair of juxtarenal or suprarenal abdominal aortic aneurysms and visceral vessel occlusive disease, fewer postoperative complications, decreased postoperative third-space fluid losses from intraoperative evaporation and ileus, and improved postoperative pulmonary function. Atherosclerosis was most common cause of abdominal aortic aneurysm. Dacron graft[18mm] was replaced successfully.Postoperative course was uneventful and he was discharged in good condition.

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Proliferation of Keratinocytes Induced by Adipose-Derived Stem Cells on a Chitosan Scaffold and Its Role in Wound Healing, a Review

  • Gomathysankar, Sankaralakshmi;Halim, Ahmad Sukari;Yaacob, Nik Soriani
    • Archives of Plastic Surgery
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    • v.41 no.5
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    • pp.452-457
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    • 2014
  • In the field of tissue engineering and reconstruction, the development of efficient biomaterial is in high demand to achieve uncomplicated wound healing. Chronic wounds and excessive scarring are the major complications of tissue repair and, as this inadequate healing continues to increase, novel therapies and treatments for dysfunctional skin repair and reconstruction are important. This paper reviews the various aspects of the complications related to wound healing and focuses on chitosan because of its unique function in accelerating wound healing. The proliferation of keratinocytes is essential for wound closure, and adipose-derived stem cells play a significant role in wound healing. Thus, chitosan in combination with keratinocytes and adipose-derived stem cells may act as a vehicle for delivering cells, which would increase the proliferation of keratinocytes and help complete recovery from injuries.