• 대한기계학회논문집B
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• 제22권7호
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• pp.1022-1029
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• 1998

The relation of the inlet fuel distribution, velocity, and overall equivalence ratio to the stability of a lean burning no-swirl dump combustor was examined. Premixed or partially premixed natural gas was introduced into the air stream, which flowed to the dump region through an annular inlet pipe. Inlet air was preheated upto 400 deg.C. Combustion instability was observed to occur at higher value of equivalence ratio (> 0.6) as the degree of unpremixedness was increased. Instabilities exhibited a dominant frequency of ~ 500 Hz, which corresponded to a half wave mode of combustor. CH chemiluminescence and pressure fluctuations were in-phase when combustion instabilities occurred. Acetone LIF images revealed that there was a strong fuel concentration gradient across the inlet annulus. Phase resolved OH LIF images showed that inlet fuel distribution was affected by the combustion instabilities.

• The Journal of Korean Physical Therapy
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• 제2권1호
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• pp.103-112
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• 1990

The intervertebral disc in the anterior portion of the function unit gives the spine its flexibility. The disc is attached closely to the vertebral endplates. Between these endplates and the annulus fibrosus, the nucleus pulposus of the lumbar disc is enclosed in a circle of unyielding tissues. Compressive pressure placed on the disc is dissipated circumferentially in a passive manner In response to the greater axial forced exerted on the lumbar spine in comparison to the cervical and thoracic spines, the nucleus pulposus has its greatest surface area in the lumbar spine. The intervertebral disc is not only structure that helps diss pate stresses placed on the spine. With flexion, extension, rotation, or shear stress, the load distribution on the function unit is shared by the intervertebral disc, anterior and posterior longitudinal ligaments, the facet joints and capsules, and other ligamentous structures like the ligamentum flavum, interspinous and supraspinous ligaments, which attach to the posterior elements of the functional unit.

• Journal of Chest Surgery
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• 제25권5호
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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.

• Journal of Chest Surgery
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• 제27권6호
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• pp.472-476
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• 1994

The incidence of single coronary artery is extremely rare in a review of congenital anomalies of the coronary arteries. This 27-year-old male patient was referred for the evaluation of cardiac condition showing exertional dyspnea[NYHA class II-III] and chest discomfort for about 1 year. A complete catheterization study including angiogram disclosed large single coronary artery arising from left aortic sinus [Ogden classification L-4] associated with bicuspid aortic valvular stenosis and low grade supravalvular aortic stenosis. Calcified stenotic aortic valve was fully removed with caution and the 19mm St. Jude Medical valve was then implanted in the small nortic annulus. The patient had an uneventful recovery and was discharged on 13th postoperative day.

• Journal of Chest Surgery
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• 제44권1호
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• pp.58-60
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• 2011

A seventeen-month-old male baby, who had received conventional biventricular repair for congenitally corrected transposition of the great arteries, underwent excision of supratricuspid ring. Although tricuspid valve annulus was marginally small on direct inspection in the operating theater, circumferential excision of supratricuspid ring alone completely relieved the right ventricular inflow obstruction.

• Journal of Welding and Joining
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• 제29권6호
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• pp.45-48
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• 2011

In this research, laser welding of automotive transmission components was investigated to replace electron beam welding which is normally conducted under vacuum condition. Fiber laser welding was applied to the automotive transmission components - hub clutch and annulus gear. In the component welding, the laser welding parameters were optimized to eliminate spatters and the end crater. By applying laser welding to the transmission parts, the process time could be reduced up to 70% compared with the current electron beam welding process.

• Parasites, Hosts and Diseases
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• 제25권2호
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• pp.207-209
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• 1987

A systematic mosquito taxonomic study in Korea was established by Lee in 1971. Since then, many species have been recorded as new to Korea. However, much of this taxonomic information has been distributed in a number of scientific publications. This fork attempts to combine this information into a single document, as well as to synthesize revised taxonomic synonyms of species cccurring in Korea. Four species, Culex vora.x, Culex kangi, Aedes kobayashii and Culiseta kanayamensis listed in our previous paper, are synonyms of Culex kalifaxii, Cutex jackseni, Aedes alehtorowi and Culiseta bergrothi, respectively. Culex annulus is a misidentified species of Culex pseudovishnui. The subspecies Cutes pipiens quinquefassiatus and subgenus Manscnia (Ccquillettidia) were treated as full species and genus respectively in a catalog of the mosquitoes of the world. However, not all current authors agree to those specific and generic treatment. Based on available publications the total number of mosquito species recorded in Korea is now 52 representing 9 genera. Forty-five of these 52 are confirmed species with preserved specimen representation. As collection of specimen continues, there is a possibility that representative of 7 unconfirmed species will be found. 1 hope this paper will provide useful information for entomology workers who are interested in mosquito taxonomy in Korea.

• 설비공학논문집
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• 제18권4호
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• pp.370-376
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• 2006

The paper concerns an experimental study of fully developed laminar flow of a Newtonian and non-Newtonian liquid in concentric annuli with combined bulk axial flow and inner cylinder rotation. Pressure losses and skin friction coefficients have been measured for Newtonian fluid, water and non-Newtonian fluids, 0.2% aqueous of sodium carboxymethyl cellulose (CMC) and 5% bentonite solutions, when the inner cylinder rotates at the speed of $0{\sim}500$ rpm. The influences of rotation, radius ratio and working fluid on the annular flow field are investigated. And the new correlations among the skin friction coefficient, the Reynolds number and the Rossby number are presented with reasonable limits of accuracy in laminar flow regime.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.291-295
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• 1996

In CANDU reactor, each pressure tubes contain twelve fuel bundles and provide the inlet and outlet for the primary coolant. If a leak develops in the pressure tube, it is detected by Annulus Gas System which contains circulating dry $CO_2$ gas. Since the leaks caused by the flaws are resulted in pressure tube break, establishment of flaw assessment method is very significant in view of the fracture mechanics. In this paper, various criteria for assessing the flaws are presented to prevent the tube rupture and ensure the integrity of reactor operating.

• 대한수의학회지
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• 제59권3호
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• pp.165-169
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• 2019

A 6-year-old Dachshund was presented with acute, non-localized pain without neurological dysfunction. Radiography revealed multiple calcifications of intervertebral discs and narrowing of disc space in the thoracolumbar region. Computed tomography and magnetic resonance imaging revealed calcified disc-like material entrapped in the left extraforaminal area and showed a displaced nerve root. Fenestration and removal of the extruded disc material were performed in a routine manner. Histopathological examination showed degenerative disc materials with severe calcification both in the nucleus pulposus and around the annulus fibrosis. Based on imaging, surgical, and histopathologic results, the dog was diagnosed with far lateral lumbar disc extrusion.