• Journal of Chest Surgery
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• v.19 no.3
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• pp.457-463
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• 1986

Truncus Arteriosus is uncommon, accounting for 0.4%-2.8% of all congenital cardiac malformations. Truncus arteriosus has a poor prognosis in early infancy and defined as "a single arterial trunk that leaves the heart by way of a single arterial valve and that gives rise to the coronary, systemic and one or both pulmonary arteries directly." Through antemortem study of patients with truncus arteriosus the development of surgical techniques for palliation and correction was established. Recently we had surgical experience of truncus arteriosus - Collett '||'&'||' Edwards type 2. The main pulmonary artery was originated from truncus at right posterolateral aspect. Truncal valve was tricuspid with good coaptation. Ventricular septal defect was subarterial type of 2.0 cm in diameter. After detachment of the main pulmonary artery from truncus, truncus was repaired directly. Ventricular septal defect was closed with Dacron patch. Extracardiac valved conduit [Carpentier-Edwards: 16mm] was employed for making continuity between right ventricular outflow tract and pulmonary artery. Postoperatively, incomplete right bundle branch block on electrocardiogram was continued. Patient was died due to respiratory failure in postoperative 40 days.s.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.490-495
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• 1998

In this paper an asymmetric hydraulic actuator which consists of single acting cylinder and servo valve is modeled for a quarter car active suspension system. This model regards the force as an internal state rather than a control input. The control input of the model is the sum of oil flows that pass through the valve's orifices. The resulting dynamic equation in the state space ap-pears a feedback connection of a nominal linear time in-variant term with a nonlinear bounded uncertain block. Since this model makes it possible to eliminate the force control phase, analysis and controller design are made straightforward and simple. Well known LQR method is then applied. Simulation and test rig experiment show the effectiveness of this approach in modeling and control.

• Computers and Concrete
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• v.24 no.5
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• pp.437-444
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• 2019

PLC and its expansion module, electric ball valve and cooling pipe, electric heating steel plate and various components of the system, which is used to control test and process data. By automatically adjusting the opening of the valve, the system makes the top temperature and cooling speed develop along the ideal temperature diachronic curve. Moreover, the system enables the temperature difference between inside and surface of test block limited in a given range by automatically controlling the surface board heating. The method of physical simulation test by sandbox with built-in cooling water pipe and heating rod is adopted. On the premise of a given standard value, the operation of the system is checked under different working conditions. Further, an extension of this system is proposed, which enables its application to obtain some thermal parameters when cooperating with numerical simulation.

• Journal of Veterinary Clinics
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• v.25 no.3
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• pp.195-199
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• 2008

A 2-year-old female Maltese dog was referred with primary complaints of exercise intolerance and abnormal heart sound. Clinical and diagnostic investigation revealed split S2 and S4 gallop in the cardiac auscultation, tall P wave and left anterior fascicular block in the electrocardiogram, left atrial enlargement on the thoracic radiography, ostium primum atrial septal defect and cleft of the anterior leaflet of the mitral valve on the echocardiography. Based on those findings, the dog was diagnosed as the partial atrioventricular canal defect. Since the dog showed mild exercise intolerance, enalapril and furosemide were prescribed.

• Journal of Chest Surgery
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• v.23 no.1
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• pp.41-48
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• 1990

Thirteen patients underwent repair of atrioventricular septal defect [AVSD] from January 1980 to July 1989 at Kyungpook National University Hospital. Two patients had complete AVSD [Rastelli type A] and eleven patients had partial AVSD [ostium primum atrial septal defect and cleft of anterior mitral leaflet]. In all the patients of partial AVSD, atrial septal defect was closed with Dacron patch and the mitral cleft was approximated with interrupted simple sutures. In one patient of complete AVSD, one patch technique was used to close the atrial and ventricular septal defect, and in the other patient of complete AVSD, two patch technique was used. In six patients, there were associated anomalies; four had isolated ostium secundum ASD, two had patent foramen ovale. Postoperative complete A-V block was noted in a patient of partial AVSD, but it was returned to 1st degree A-V block 30 months later and in another case of partial AVSD, severe congestive heart failure [NYHA functional class IV] due to residual mitral insufficiency was developed postoperatively, but this patient was recovered to the state of functional class I after receiving mitral valve replacement. There was one hospital death [8 %] resulting from low cardiac output.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.647-650
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• 2001

In case of bent axis type axial piston hydraulic pump or motor, hydrostatic bearing used to achieve the lubrication effect on the mechanical sliding contact areas between the following pairs ; piston shoe and swash plate, valve plate and cylinder block, piston and cylinder block, etc. In this research, we designed two pairs of spherical ball joint in witch connecting rod piston end. The one is not hydrostatic bearing, the other is designed with spherical hydrostatic bearing in point of view minimum pumping power loss. By varying supply pressure on the piston, we can know that it is possible to reduce the friction torque by using hydrostatic bearing designed one. Finally, by comparing the results of driving torque between the two models, it was verified that the spherical hydrostatic bearing is well designed.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.34-35
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• 2002

CoCrPt alloy films are attracting wide attention for applications to high-density magnetic recording media and hard magnetic layer in spin valve structure due to their high coercivity and strong magnetocrystalline anisotropy. Diblock copolymer templates are one of the most promising candidates for nanoscale patterning otherwise inaccessible by lithographic procedures [1]. In this study, we have investigated magnetic properties of Co$\sub$68/Cr$\sub$18/Pt$\sub$14/ nanodot arrays made by self-assembling polystyrene-block-methyl methacrylate ((PS-b-PMMA), (Mn = 82.5 Kg/mol, with a 1.12 polydispersity)) diblock copolymer. (omitted)

• Journal of Chest Surgery
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• v.26 no.5
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• pp.403-408
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• 1993

The atrioventricular node reentrant tachycardia[AVNRT] is a common type of supraventricular tachycardias. Recently we experienced two cases of AVNRT. One is AVNRT with severe aortic regurgitation[grade IV] and the other is AVNRT with patent ductus arteriosus. Dissection of perinodal tissue has been successfully carried out in the beating heart under the normothermic cardiopulmonary bypass, and aortic valve replacement and ligation of patent ductus arteriosus were also performed, respectively. Postoperatively, permanent atrioventricular block was not occured and AVNRT was not developed during the follow up. We propose that the surgical dissection of perinodal tissue is a simple and effective treatment for the patient with refractory AVNRT.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.213-219
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• 2013

This study examined the static characteristics of a spool valve with a hybrid lap between the spool land and the sleeve. The static equation for the pressure characteristics was derived from flow equations that depend on the spool displacement, and the final model was derived from $q_a=q_b=0$ because the pressure characteristics test needs to block the control port in the valve. The static equation for the flow characteristics was derived from the pressure characteristics when the control port is open ($q_a=q_b$, $p_a=p_b$). The characteristic equation in the shifted region was assumed from the proportional relationship between the pressure-flow characteristics and the spool displacement.

• Journal of Chest Surgery
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• v.36 no.9
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• pp.633-637
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• 2003

Sometimes temporary tricuspid valve detachment is applied for closure of ventricular septal defect to facilitate good exposure and avoiding ventriculotomy, but most surgeons hesitate to do it in the fear of tricuspid incompetence. Moreover in recent textbooks the technique of temporary tricuspid detachment is only described for exceptional situations and is not further analysed or commented on. Material and Method: Retrospective study was carried out in all 11 patients operated between 1985 to 1994, with preoperative data and postoperative course and recent echocardiographic and electrocardiographic data. Result: On the basis of the area of the color flow jet, tricuspid valvular regurgitation was graded as none in 9 and trivial in 2, and significant electrocardiographic heart block did not developed in any patients. Conclusion: Takedown and attachment of the tricuspid valve is a safe and effective technique that improves exposure for ventricular septal defect, and does not adversely effect tricuspid valve competence and electrocardiography.