• The Korean Journal of Nuclear Medicine
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• v.19 no.1
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• pp.67-72
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• 1985

The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload(that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients(that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.2
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• pp.13-24
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• 1988

A geometrically nonlinear analysis procedure for plane frame structures in order to study the static and dynamic post-buckling behavior of these structures subjected to circulatory forces is presented. The elastic and geometric stiffness matrices, the mass matrix and load correction stiffness matrix are derived from the extended virtual work principle, where the tangent stiffness matrix becomes non-symmetric due to the effects of non-conservative circulatory forces. The dynamic analysis of plane frame structures subjected to circulatory forces in pre- and post-buckling ranges is carried out by integrating the equations of motion directly by the numerically stable Newmark method. Numerical results are presented in order to demonstrate the vality and accuracy of the proposed procedure.

• Journal of Chest Surgery
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• v.30 no.12
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• pp.1247-1250
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• 1997

A 13-year-old boy presented with anterior chest wall depression and dyspnea on exertion(NYHA II). He underwent Ravitch operation for pectus excavatum 7 years ago. A preoperative echocardiographic study revealed secundum atrial septal defect. He had no other abnormality of laboratory test, except FVC and FEVI were decreased into 2.03 L(7 %) and 1.82 L(71 %). He underwent repair of secondary anterior chest wall deformity and secundum atrial septal defect. We used unique method, raising sternum at right angle to secure good operative field for open heart surgery. Acute respiratory insufficiency was developed on postoperative day 1. Mechanical ventilation was applied which could be weaned on postoperative day 6 and thereafter hospital course was uneventful without any other sequale. He was discharged on postoperative day 19.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.2
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• pp.163-171
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• 2020

A model test for assessment of towing stability and seakeeping of a multi-purpose mobile base (MMB) was performed in calm water and wave conditions. Scale ratio of the MMB was 1/48. Tension of the towing line was measured during tests to estimate effective power to tow the full scale MMB. The tests were repeated with towing speed. In addition, an inertial measurement unit was used to measure six DOF motion of the model. Seakeeping performance was assessed through the captive model test.

• Korean Journal of Psychosomatic Medicine
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• v.5 no.1
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• pp.118-122
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• 1997

We experienced a case of 51-year-old female patient who showed symptoms of persecutory delusion, auditory hallucination and hallucinatory behavior, severe insomnia, psychomotor retardation and social withdrawal, along with some clinical signs of the deficiency of various hormones those gradually progressed after massive postpartum vaginal bleeding 13 years ago. She was admitted to a psychiatric ward under the impression of psychotic depression. However careful history taking and evaluation of clinical feature gave rise to the possibility of underlying medical condition. Laboratory work-up revealed panhypopituitarism, hypoglycemia and hyponatremia. After replacement of thyroid hormone and cortisol for 1 week, her clinical symptoms including psychiatric symptoms were improved. Taken together, these findings were compatible with the diagnosis of Sheehan's syndrome. On reporting this case, we would like to emphasize again the importance of differential diagnosis of medical problems causing psychiatric symptoms those are easily neglected in the clinical approach toward psychiatric patients.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.724-728
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• 2001

In this study, the dielectric breakdown of epoxy composites used for transformers was experimented and then its data were simulated by Weibull distribution probability. The dielectric breakdown characteristics origin in epoxy composites were examined and various effects of dielectric breakdown on epoxy composites were also discussed. As a result, first of all, speaking of dielectric breakdown properties, the more hardener increased the stronger breakdown strength at low temperature because of cross-linked density by the virtue of ester radical. And the breakdown strength of specimens with filler was lower than it of non-filler specimens because it is believed that the adding filler forms interface and charge is accumulated in it, therefore the molecular motility is raised, the electric field is concentrated, and the acceleration of electron and the growth of electron avalanche are early accomplished. In the case of filled specimens with treating silane, the breakdown strength become much higher since this suggests that silane coupling agent improves interfacial combination and relaxs electric field concentration. Finally, from the analysis of weibull distribution, it was confirmed that as the allowed breakdown probability was given by 0.1%, the applied field value needed to be under 21.5㎹/cm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.779-783
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• 2002

The dielectric breakdown of epoxy composites used for transformers was experimented and then its data were simulated by Weibull distribution probability. As a result, first of all, speaking of dielectric breakdown properties, the more hardener increased the stronger breakdown strength at low temperature because of cross-linked density by the virtue of ester radical. And the breakdown strength of specimens with filler was lower than it of non-filler specimens because it is believed that the adding filler forms interface and charge is accumulated in it, therefore the molecular motility is raised, the electric field is concentrated, and the acceleration of electron and the growth of electron avalanche are early accomplished. In the case of filled specimens with treating silane, the breakdown strength become much higher since this suggests that silane coupling agent improves interfacial combination and relaxs electric field concentration. Finally, from the analysis of weibull distribution, it was confirmed that as the allowed breakdown probability was given by 0.1%, the applied field value needed to be under 21.5MVcm.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.1
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• pp.80-88
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• 2018

The function of a vehicle holding device (VHD) is to securely hold a launch vehicle on the launch pad and release the launch vehicle at maximum thrust after engine ignition to allow lift-off of the launch vehicle. During the release of the launch vehicle, to prevent the Ka doing a doing a doing mode, which is the vertical oscillation of the entire liquid propellant, the release of the launch vehicle should be gradual. In this study, for the gradual release of a launch vehicle, a hydraulic system comprising an accumulator and pyro valve to operate a hydraulic cylinder and control the speed of the cylinder with an orifice is introduced. Through a test, the influence of design variables on the cylinder speed is analyzed. Based on this, the design values of the hydraulic cylinder are determined. Through this study, the engineering basis for developing a VHD releasing a launch vehicle at maximum thrust is provided.

• Bulletin of the Society of Naval Architects of Korea
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• v.6 no.1
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• pp.1-24
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• 1969

Added masses of two-dimensional cylinders of curvilinear-element sections with chines, which are similar to marked V character ship sections with either single or double chines, oscillating at high frequency in a free surface of an ideal fluid are calculated for both vertical and horizontal vibration by employing two particular two-parameter families of the conformal transformation. The numerical results are graphically presented in the forms of added mass coefficient curves in terms of the sectional area coefficient and the half beam-draft ratio together with the section contours derived with the employed transformations, and discussed in comparision with those of the Lewis forms and of straightline-element sections with single chine for vertical vibration, and, for horizontal vibration, with those of the Lewis forms.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.525-534
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• 2022

This investigation used two different geophysical logging techniques to confirm the depth to which a sheet pile was driven. Depth was estimated through analysis of the movement speed and three-component movement directions of a P-wave transmitted through the ground. It was also estimated by pole-pole and pole-dipole methods using electrical data logging to measure apparent resistivity. The two methods' respective results were 9.0 m (±1.5 m) and 7.5 m. As field ground conditions will include mixtures of various materials, electrical data logging is judged to be suitable for assessing depth due to its low signal-to-noise ratio.