• The Journal of Korean Physical Therapy
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• v.22 no.6
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• pp.21-28
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• 2010

Purpose: The purpose of this study was to investigate the kinematic adaptation of head and trunk to ascend stairs and a ramp. Subjects were healthy young adults. Three-dimensional kinematic patterns of head and trunk movements were examined during stair climbing and steeper ramp climbing. Methods: Fourteen young subjects with no history of chronic or acute musculoskeletal, cardiovascular or respiratory disorders took part in this experiment. Kinematic data were collected using a 6 camera Vicon system (Oxford Metrix, Oxford, England). Repeated measures ANOVA analyses were used to investigate the effect of gait mode on kinematics of the head and trunk. Results: The angle of the trunk while ascending stairs or a ramp was modified in three human planes (p<0.05). The angle of head and neck during the ascending of stairs or a ramp was not changed in the sagittal plane but was changed in the frontal and transverse planes (p<0.05). Conclusion: This study describes and discusses some basic kinematic mechanisms underlying the pattern of head and trunk changes during stair and ramp climbing and showed that postural adaptation of the head and trunk is necessary to maintain balance.

• Journal of the Korean Society of Visualization
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• v.8 no.4
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• pp.48-53
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• 2010

Water-uptake through roots, is an essential process of the water flow in plants. Its visualization is very useful for understanding sap flow dynamics at whole plant level. In this study, the tips of Arabidopsis' root hairs were excised and exposed to repeated dehydration and rehydration processes. The water-refilling through individual xylem vessels was visualized using the synchrotron X-ray micro-imaging technique. The high temporal resolution ($2\;{\mu}m$) and beam intensity of the X-ray source allowed to acquisition of consecutive X-ray images of the water-refilling process up to 10 frames/sec. Various flow patterns were observed and the ascending speed of the water-air interfaces was analyzed. The relation between the water-rising height and ascending speed was also analyzed. The present results would provide better alternative for investigating sap flows in roots.

• Journal of Chest Surgery
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• v.25 no.8
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• pp.877-884
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• 1992

From October, 1986, to June, 1992 16 patients, 13 male and 3 female patients ranging in age 28 to 70 years, were operated on for thoracic aortic aneurysm, The etiology of these patients was atherosclerotic in 10, cystic medial necrosis in 4, and trauma in 2 cases, All patients were treated by use of CPB and circulatory arrest was applicated in one patient, Ten patients had aneurysms involving ascending aorta and six patients had descending aortic aneurysm, Among ten patients with ascending aortic aneurysm, annuloaortic ectasia with aortic regurgitation were seven and all underwent surgery with composite technique [Bentall operation], The other six patients with descending thoracic aneurysm were performed graft replacement. There was no early mortality but two late deaths occurred due to cerebral hemorrhage and renal problems at POD 3mo and 39mo respectively, We obtained satisfactory long-term results and overall survival rate at 5 year was 74.7%.

• Journal of Chest Surgery
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• v.33 no.9
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• pp.748-751
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• 2000

The diffuse form of supravalvar aortic stenosis represents a surgical challenge when the ascending aorta, aortic arch, proximal descending thoracic aorta and arch arteries are involved. It can be treated by a variety of surgical approaches. We report a case of severe diffuse supravalvar aortic stenosis combined with an aortic valve anomaly and occlusion of the right coronary artery ostium in a 14-year-old boy with Williams syndrome. We enlarged the aortic root(Nick's procedure), ascending aorta, aortic arch, proximal descending thoracic aorta, and innominate artery with patches and replaced aortic valve with 19 mm St. Jude valve. Deep hypothermic circulatory arrest and retrograde cerebral perfusion were used during repair of the arch and arch artery.

• Journal of Chest Surgery
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• v.21 no.1
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• pp.158-163
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• 1988

12 Patients with thoracic aortic aneurysm were operated between May 1985 to Sept. 1987 at the our department, Hanyang University Hospital. We retrospectively evaluated the surgical results and considered diagnosis, surgical approach and perioperative problems of thoracic aortic aneurysm. There are 9 males and 3 females in the patients. The age ranged from 23 to 61 years with the mean age at 40.6 years. The cause of the aneurysm was atherosclerosis in 5, Marfan`s syndrome in 4, syphilis In 1, trauma in 1 and annuloaortic ectasia in 1 case. According to DeBakey`s classification, Type I was 1 case, Type II was 5 cases and Type III was 6 cases. Among 6 patients with ascending aortic aneurysm, Bentall`s operation in 4 cases and ascending aorta reconstruction using to Dacron Tube Graft in 2 cases were performed successfully. 6 cases with descending aortic aneurysm were managed by prosthetic graft replacement. Chylothorax was observed in 1 patient and postoperative hemorrhage necessitating reopening of the chest occurred in 4 of operative survivors. There were 2 hospital deaths; one patient was dead during the operation and one patient was dead during the post-operative course due to low cardiac output syndrome

• Journal of Chest Surgery
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• v.28 no.1
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• pp.65-68
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• 1995

Pectus excavatum occasionally occurs in patients who have underlying cardiac disease, especially Marfan syndrome. This report describes a patient with pectus excavatum who had ascending aortic aneurysm with aortic regurgitation and anterior leaflet prolapse of mitral valve. This patient underwent replacement of aortic valve and ascending aorta with 25 mm SJM valved conduit graft[Bentall operation with Cabrol shunt , and mitral valve replacement with SJM 31 mm, the pectus excavatum was corrected at the time of completion of the intracardiac operation with the modified sternal turnover. This procedure offered excellent operative exposure for the inracardiac operation with prevention of low cardiac output after operation due to depressed sternum and maintained chest wall stability resulting good cosmetic chest wall appearance. This patient recovered and discharged in good postoperative result with minimal temporary peroneal nerve palsy in his left leg.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.6
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• pp.525-529
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• 2016

In the case of a motor system that converts electrical energy into mechanical energy, the region of the motor and that of the generator coexists. In the case of an escalator, the ascending escalator is operated by the motor, whereas the descending escalator is operated by the generator according to the load. To evaluate the proposed method, this study reduces the power of the ascending escalator up to approximately 35% by sharing the regeneration power of the descending escalator. The loss of transfer power nearly exists in the case of the proposed method. Furthermore, the lifetime of the DC link condenser can be extended because it is connected in parallel, thus leading to a twofold increase in capacity.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.413-421
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• 1997

This paper presents the comparison and evaluation of the existing test results and empirical formulas of high-strength concrete available in the literature for various types of models to describe the stress-strain relationship. The range of concrete compressive strength taken into account in this study was 400 to 1200kg/㎠ and the comprehensive assessment of each linearly varying ascending part and brittle type of descending one of each model was carried out. The results show that the fixed curve equation seems to be recommended to well describe the ascending part and so does Fafitis' exponential equation for the descending part in the stress-strain relationship of the high and ultra high-strength concrete.

• Carbon letters
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• v.7 no.4
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• pp.271-276
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• 2006

Porous carbon materials were prepared with a thermal treatment of coal tar pitch at 550 in the Ar gas. Growth, merger, and distribution of pore were characterized with scanning electron microscopy as variation ascending temperature gradient and chamber pressure. After graphitizing at the 2600 (1 hr.), walls and connecting parts between pores were investigated with X-ray diffraction patterns. Wall thickness and pore size decreases as increasing ascending temperature gradient, and pore size becomes homogeneous. Graphite quality and thermal conductivity become higher due to the enhanced orientation of walls and connecting parts between pores.

• Journal of Chest Surgery
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• v.25 no.5
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• pp.550-554
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• 1992

The selection of an appropriate surgical technique for repair of aneurysm of the ascending aortia with aortic insufficiency is unsettled. The etiology of the disease process has been the best indicator for the type of repair. Placement of a supracoronary graft[seperate graft and valve] is a compromise if the coronary ostia are displaced cephalad by the aneurysm, where as insertion of a valved conduit is difficult and unnecessary if the coronary ostia are normally placed. A 53 year old female patient underwent primary repaiar of proximal dissected layer and aortic valve replacement with 24mm carbomedics, The operative findings consisted of a supravalvular intimal tear, cicumferential dissection, dilated aortic annulus and normal position of coronary ostia. She is good physical activity now llmonths posoperatively.