• 제목/요약/키워드: retraction

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Surgical Treatment of Chronic Constrictive Pericarditis -Report of 4 ases- (만성 교약성 심낭염의 외과적 치료 -4례 보고-)

  • 전희재
    • Journal of Chest Surgery
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    • v.27 no.9
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    • pp.793-797
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    • 1994
  • Constrictive pericarditis is often accompanied with ~brothorax and deterioration of cardiac, hemodynamic functions. Surgical relief of fibrous peel causes remarkable improvement in pulmonary, cardiac, hemodynamic function, and subjective symptoms. We experienced 4 cases of constrictive pericarditis combined with bilateral ~brothorax after bilateral pleural effusion caused by tuberculosis and non-specific inflammation. Pleural decortication and pericardiectomy were done at the same time through anterolateral thoracotomy with sternal transection[3 patients] and median sternotomy incision[l patient]. Low cardiac output was the most common complication. With left anterolateral thoracotomy, we could prevent the hypotension from massive retraction for dissecting by median sternotomy, which was good for dissecting from anterior wall of left ventricle to posterior wall of left ventricle and surrounding phrenic nerve. It was enough to dissect the portion being through hard to dissect, right atrium, SVC and IVC.

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Continuous Tool-path Generation for High Speed Machining

  • Lee, Eung-Ki;Hong, Won-Pyo;Park, Jong-Geun
    • International Journal of Precision Engineering and Manufacturing
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    • v.3 no.4
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    • pp.31-36
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    • 2002
  • A continuous tool-path, that is to cut continuously with the minimum number of cutter retractions during the cutting operations, is developed in order to minimise the fluctuation of cutting load and the possibility of chipping on the cutting edge in HSM (high-speed machining). This algorithm begins with the offset procedure along the boundary curve of the sculptured surface being machined. In the of offset procedure, the offset distance is determined such that the scallop height maintains a constant roughness to ensure higher levels of efficiency and quality in high-speed machining. Then, the continuous path is generated as a kind of the diagonal curve between the offset curves. This path strategy is able to connect to neighbor paths without cutter retractions. Therefore, the minimum tool retraction tool-path can be generated And, it allows the sculptured surface incorporating both steep and flat areas to be high-speed machined.

Free Vibration and Dynamic Stability of the Axially Moving Continuum with Time-varying Length (축방향으로 이동하며 길이가 변하는 연속체의 자유 진동 및 동적 안정성)

  • 사재천;이민형;이승엽
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.4
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    • pp.272-279
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    • 2002
  • The time-dependent frequency and energy of free vibration of the spagetti problem, that is the axially moving continuum with time-varying length, are investigated. Exact expressions for the natural frequency and time-varying vibration energy are derived by dealing with traveling waves. The vibration period increases with increasing length, but the free vibration energy decreases. When the string undergoes retraction, the vibration energy increases with time. The free response of the time-varying string is represented by superposing two traveling waves.

Development of a Gripper for Robotic Transplanter and Evaluation of Its Transplanting Performance (육묘용 로봇이식기 그리퍼의 개발 및 이식 성능 평가)

  • 류관희;김기영;박정인
    • Journal of Biosystems Engineering
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    • v.23 no.3
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    • pp.271-276
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    • 1998
  • A gripper mechanical design using a pneumatic system was developed to successfully grip, hold, and release a seedling plug for transplanting it. The gripper comprised of two air cylinders and shovel-type fingers. The gripper can grasp and hold a seedling by sliding the two fingers attached to the two separate air-cylinders, mounted at an angle of 15$^{\circ}$ When releasing a plug, retraction of the fingers gives a seedling little attachment to the gripper. To prevent seedling from attaching to the fingers, press-plates were attached to the end of the gipper. Transplanting performance of the developed gripper was tested with cucumber seedlings at different soil moisture contents. Overall transplanting performance of developed gipper was higher than the performance of the previously developed gripper. Best transplanting result was achieved at medium level of soil moisture content.

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Endodermal Cyst of the Posterior Fossa

  • Lee, Chul-Woo;Yoon, Seok-Mann;Kim, Yoon-Jung;Yun, Il-Gyu
    • Journal of Korean Neurosurgical Society
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    • v.37 no.4
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    • pp.310-312
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    • 2005
  • We report a case of endodermal cyst of the posterior fossa. A 44-year-old man presented with headache for three months. Computed tomography and magnetic resonance imaging revealed a $6{\times}2.5{\times}2cm$ sized extra-axial non-enhancing cystic lesion on the ventral aspect to brain stem. To avoid retraction injury to brain stem, far lateral transcondylar approach was selected. Right suboccipital craniotomy and partial removal of occipital condyle with resection of C-1 and C-2 hemilaminae exposed the extra-axial cyst well. The cyst has a whitish thick membrane. It was not adherent to brain stem and lower cranial nerves. Total removal of the cyst was done without difficulty. Histological analysis disclosed a layer of pseudostratified columnar epithelium with basement membrane. The result of immunohistochemical study was consistent with endodermal cyst.

Treatment of the infant with bilateral cleft lip and palate (양측성 구순구개열 신생아의 치료)

  • Kim Su Jung;Kang Seung Goo;Lee Young Jun;Park Young Guk
    • Korean Journal of Cleft Lip And Palate
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    • v.6 no.2
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    • pp.107-115
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    • 2003
  • The case unveils an early orthodontic intervention on 3-week old infant innately with bilateral cleft lip and palate. Presurgical Nasoalveolar Molding(PNAM) procedures were carried out for 2 months for the sake to diminish the anticipated strain of postsurgical scar by means of the retraction of protruded premaxilla and the extension of collapsed columella. The gap on the alveolar cleft decreased by 2,5 mm, and the columella manifested 1. 5 mm increase of its length, which yielded the consequent downward and backward movement of premaxilla, and expected to bring down the technical complexity of primary lip surgery. PNAM with sophisticated technical procedures at an optimal timing disclosed the passive molding of the alveolar segments and the formation of nasolabial soft tissue integuments and permitted one-time primary lip surgery.

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PHASE VARIATION IN DOPPLER SIGNAL FOR VARIOUS OPTICAL PARAMETERS

  • Son, Jung-Young;Kim, Myung-Sik;Oh, Myung-Kwan
    • Proceedings of the KIEE Conference
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    • 1989.07a
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    • pp.629-632
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    • 1989
  • The scattered light intensity from a spherical particle passing through the cross-over region of two coherent laser beams, varies periodically. Photodetection of this light beams produces a periodic signal of varying amplitude. The phase of the signal varies with the particle size and refractive index, the beam crossing angle and wavelength, and the position and size of the scattered ligth collecting aperture. In this paper the phase variation with respect to the particle absorptive index of retraction, collecting lens size and beam crossing angle is calculated using both Mie scattering theory and reflection theory. The two theories show good agreement in phase predictions, especially for large absorptive indices and for small collection lenses. Both theories predict phase to be inversely proportional to the beam crossing angle.

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Vibration Characteristics of the Axially Moving Continuum with Time-Varying Length: Spagetti Problem (축방향으로 이동하며 길이가 변하는 연속체의 진동특성: 스파게티 문제에 응용)

  • 사재천;이승엽;이민형
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.385-392
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    • 2001
  • Time-dependent frequency and energy of free vibration of the Spagetti problem, that is the axially moving continuum with time-varying length, are investigated. Exact expressions for the natural frequency and time-varying vibration energy are derived by dealing with traveling waves. When the string length is increased, the vibration period increases, but the free vibration energy varies as a function of both translating velocity and boundary velocity of the continuum. However, when the string undergoes retraction, the vibration energy increases with time, String tension together with non-zero instantaneous velocity at the moving boundary results in energy variation.

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The p110${\gamma}$ PI-3 Kinase is Required for the Mechanism by Which the EphA8-induced Neurites are Modulated by Ephrin-A5 Engagement

  • Park, Soo-Chul
    • Animal cells and systems
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    • v.8 no.1
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    • pp.57-63
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    • 2004
  • This study provides evidence that expression of EphA8 receptor in NG108-15 cells results in a substantial increase in the number of neurite-bearing cells. However, the EphA8-induced neurite outgrowth does not require either ephrin-A5 stimulation or ectopic expression of $p110{\gamma}$ PI-3 kinase. In contrast, co-expression of a lipid kinase-inactive $p110{\gamma}$ mutant together with EphA8 causes neurite retraction in the presence of ephrin-A5 stimulation. This effect was not observed in the absence of ephrin-A5 stimulation. Significantly, the tyrosine kinase activity of EphA8 is not important for either of these processes. Taken together, our results strongly suggest that $p110{\gamma}$ PI-3 kinase is critically involved in the regulatory process by which ephrin-A5 exerts effects on the EphA8-induced neurite outgrowth.

A Modified Technique for the Correction of Funnel Chest (함몰흉 교정의 변형수기)

  • 이상호
    • Journal of Chest Surgery
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    • v.33 no.10
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    • pp.806-811
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    • 2000
  • Background : The authors have modified the method of Ravitch technique. Material and Method ; This technique was applied to 6 patients out of 18 patients who underwent corrective surgery from May 1987 to July 1999. The technique is quite different from that of Ravitch. We did not divide the intercostal muscle bundles from the laterals of sternum and the Akin's struts were placed retrosternally crossing the chest horizontally to prevent flail motion during immediate post-operative period and retraction of the sternum afterwards. Anterior sternal osteotomy instead of the posterior one was performed for the latest 3 cases which made operative procedure more simple and easy. The struts were removed one year later. Result : Compared to the hospital stay of the patients who received standard Ravitch method that of the six cases who received our modification was definitely shortened from 13.1 days to 8.3 days(p<0.0000). Flail motion was not noted in any patient and chest wall stability was obtained more easily with this technique. Conclusion : Our modification is recommendable for correction of funnel chest in regards to shorter operation time better chest wall stability shorter hospital stay and less complication.

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