• Journal of Chest Surgery
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• v.13 no.3
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• pp.274-279
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• 1980

A 21 years old male student was admitted because of mediastinal mass that was noticed in routine physical examination. He complained progressive hoarseness, mild dysphagia, and anterior chest pain on deep respiration. This mediastinal mass was diagnosed as aortic aneurysm involving ascending, transverse, and descending thoracic aorta with aid of aortogram. Total prosthetic replacement of aneurysm was performed successfully using extracorporeal circulation and hypothermia. For myocardial protection during aortic cross clamping, cardioplegic solution was used and topical myocardial cooling was also adapted For simplicity of cardiopulmonary bypass, Y-shaped connectors took cerebral perfusion catheters to the main perfusion line beyond the arterial pump. Total bypass time was 219 minutes, and aortic cross clamp time was 104 minutes. Recovery was uneventful except respiratory insufficiency for first 4 days. Isotope aortogram checked on post operative 30th day showed normal aortic configuration. He was discharged on post operative 35th day. A follow-up chest X-ray study 5 months later showed nearly normal anatomy.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.257-262
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• 2004

A series of preliminary model tests are performed to find out the wave attenuating effect of the pneumatic breakwater of environment friendly type, which is a bubble screen generated by releasing compressed air from a submerged multiple parallel manifold Rising bubbles induce vertical current, which produces horizontal currents flowing away from the bubble-screen area in both directions. Near bottom, the corresponding currents flow toward the bubble screen, thus completing the circulation pattern. The surface current moving against the direction of wave propagation causes some attenuation of the waves. It becomes more effective as the relative depth (d/ L) increases (short-period waves in deep water). With the same air-discharge, the multiple parallel manifold can be more effective for the attenuation of longer waves through optimum arrangement of manifold number. installation depth, manifold gap, etc. The pneumatic breakwater will give a wide utilization as a device for protecting harbor facilities and as a simple, mobile breakwater.

• Ocean Science Journal
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• v.41 no.1
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• pp.1-10
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• 2006

Total sea surface temperature (SST) in a coupled GCM is diagnosed by separating the variability into signal variance and noise variance. The signal and the noise is calculated from multi-decadal simulations from the COLA anomaly coupled GCM and the interactive ensemble model by assuming both simulations have a similar signal variance. The interactive ensemble model is a new coupling strategy that is designed to increase signal to noise ratio by using an ensemble of atmospheric realizations coupled to a single ocean model. The procedure for separating the signal and the noise variability presented here does not rely on any ad hoc temporal or spatial filter. Based on these simulations, we find that the signal versus the noise of SST variability in the North Pacific is significantly different from that in the equatorial Pacific. The noise SST variability explains the majority of the total variability in the North Pacific, whereas the signal dominates in the deep tropics. It is also found that the spatial characteristics of the signal and the noise are also distinct in the North Pacific and equatorial Pacific.

• Journal of Agricultural Extension & Community Development
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• v.4 no.1
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• pp.211-229
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• 1997

An environmental problem is the greatest barrier to pursuit of mankinds existence and development. The major traits of this problem are totality and complexity, therefore the finding of environmental problem's solutions is very difficult. The eco-friendly development that pursuing the ecological principles is the direction of environmental problem's solutions. Environmentally sound and sustainable development, deep ecological thought or environmentalism, the following of god's creation order and the old oriental thought are patterns and principles of eco-friendly development. Every creature has one ecological niche from the ecological principles of adoption, competition, evolution, variety, circulation, harmony and equilibrium. Ecological niche means that every creature has ecological status and duty. Therefore finding the mankinds ecological niche is important because it is desirable directions for eco-friendly development to solve environmental problems.

• Transactions of Materials Processing
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• v.16 no.1 s.91
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• pp.20-24
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• 2007

Polypropylene substrate with hair-like nano features(aspect $ratio{\sim}10$) on the surface is fabricated by injection molding process. Pure aluminum plate is anodized to have nano pore array on the surface and used as a stamper for molding nano features, The size and the thickness of the stamper is $30mm{\times}30mm$ and 1mm. The fabricated pore is about 120nm in diameter and 1.5 um deep. For molding of a substrate with nano-hair type of surface features, the stamper is heated up over $150^{\circ}C$ before the filling stage and cooled down below $70^{\circ}C$ after filling to release the molded part. For heating the stamper, stamper itself is used as a heating element by applying electrical power directly to each end of the stamper. The stamper becomes cooled down without circulation of coolant such as water or oil. With this new stamper heating method, nano hairs with aspect ratio of about 10 was successfully injection molded. We also found the heating & cooling process of the stamper is good for releasing of molded nano-hairs.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.136-143
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• 2002

Warm draw die technique which is one of the new forming technologies to improve formability of sheet metal is applied to the cylindrical and square cup drawing of stainless-aluminum clad sheets. In experiments the temperature of die and blank holder is varied from room temperature to $180^{\circ}C$, while the punch is cooled by circulation of coolant to increase the fracture strength of workpiece on the punch comer area. Test materials chosen for experiments are STS304-A1050-STS304 clad sheets. Teflon film as a lubricant is used on both sides of a workpiece. The limit drawing ratio and relative drawing depth as well as quality of drawn cups(distribution of thickness)are investigated and validity of warm drawing process is also discussed. No separation between each laminated material after drawing occurred through inspection by microscope as well as application of penetrant remover and bond strength test. Therefore, warm forming technique was confirmed to give better results in deep drawing of stainless clad sheet metal.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.1
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• pp.55-63
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• 1997

A numerical investigation has been made for flows in an axisymmetric circular cylinder with an impulsively rotating cone located at the bottom of the container. The axisymmetric container is completely filled with a viscous fluid. Major parameter for the present research is only the vertex angle of the cone, otherwise Reynolds number and aspect ratio of the vessel are fixed. Main interest concerns on the vortex breakdown of meridional circulation by impulsive rotation of the cone with respect to the longitudinal axis of the cylinder. Numerical method has been used to integrate momentum and continuity equations on a generalized body-fitted grid system. The pattern of vortex breakdown is quite different from that in a right circular cylinder with flat endwall disks. The flow visualization photograph of the preceeding work by Escudier is compared with the present numerical results and the two results are in good agreements. Also flow data are plotted to gain a deep understanding for the present phenomena of the vortex breakdown. The conclusions of this work are clearly explained by the classical theory of the vortex flows in a finite geometry.

• Journal of Korean Society on Water Environment
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• v.31 no.4
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• pp.367-376
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• 2015

The momentum and kinetic turbulent energy carried by the wind to a stratified lake lead to basin-scale motions, which provide a major driving force for vertical and horizontal mixing. A three-dimensional (3D) hydrodynamic model was applied to Lake Tahoe, located between California and Nevada, USA, to simulate the dominant basin-scale internal waves in the deep lake. The results demonstrated that the model well represents the temporal and vertical variations of water temperature that allows the internal waves to be energized correctly at the basin scale. Both the model and thermistor chain (TC) data identified the presence of Kelvin modes and Poincare mode internal waves. The lake was weakly stratified during the study period, and produced large amplitude (up to 60 m) of internal oscillations after several wind events and partial upwelling near the southwestern lake. The partial upwelling and followed coastal jets could be an important feature of basin-scale internal waves because they can cause re-suspension and horizontal transport of fine particles from nearshore to offshore. The internal wave dynamics can be also associated with the distributions of water quality variables such as dissolved oxygen and nutrients in the lake. Thus, the basin-scale internal waves and horizontal circulation processes need to be accurately modeled for the correct simulation of the dissolved and particulate contaminants, and biogeochemical processes in the lake.

• Journal of Microbiology
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• v.43 no.spc1
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• pp.65-84
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• 2005

Invasive candidiasis is associated with high morbidity and mortality. Clinical diagnosis is complicated by a lack of specific clinical signs and symptoms of disease. Laboratory diagnosis is also complex because circulating antibodies to Candida species may occur in normal individuals as the result of commensal colonization of mucosal surfaces thereby reducing the usefulness of antibody detection for the diagnosis of this disease. In addition, Candida species antigens are often rapidly cleared from the circulation so that antigen detection tests often lack the desired level of sensitivity. Microbiological confirmation is difficult because blood cultures can be negative in up to 50% of autopsy-proven cases of deep-seated candidiasis or may only become positive late in the infection. Positive cultures from urine or mucosal surfaces do not necessarily indicate invasive disease although can occur during systemic infection. Furthermore, differences in the virulence and in the susceptibility of the various Candida species to antifungal drugs make identification to the species level important for clinical management. Newer molecular biological tests have generated interest but are not yet standardized or readily available in most clinical laboratory settings nor have they been validated in large clinical trials. Laboratory surveillance of at-risk patients could result in earlier initiation of antifungal therapy if sensitive and specific diagnostic tests, which are also cost effective, become available. This review will compare diagnostic tests currently in use as well as those under development by describing their assets and limitations for the diagnosis of invasive candidiasis.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.867-881
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• 1998

The studies were carried out to investigate the phygiological changes in deep hypothermia in rabbits. Sixty rabbits were continuously cooled with femoral arterio-venous bypass circulation to rectal temperatures of $34.0{\pm}0.3^{\circ}C$(mild hypothermia), $30.0{\pm}0.3^{\circ}C$(moderate hypothermia), and $25.0{\pm}0.3^{\circ}C$(deep hypothermia). The results obtained in these experiments were summarized as follows : In mild, moderate, and deep hypothermia, MAP, HR, RR, pH, $pCO_2$, $pO_2$, $Na^+$, $K^+$, HCT, PLT, glucose, L-lactate, BUN, and creatinine were analyzed. During hypothermia, a statistically significant decrease of MAP occurred between $30^{\circ}C$ and early $25^{\circ}C$(Start) of rectal temperature while significant increases occurred between baseline($38.7^{\circ}C$) and $30^{\circ}C$. Significant decreases of HR and RR were observed in the rabbits, particularly those changes appeared to similar patterns in proportion to hypothermia. Significant decreases of pH occurred between $34^{\circ}C$ and $25^{\circ}C$, and significant increases of $pO_2$ and $pCO_2$ were observed continuously in the hypothermic rabbits. The hypothermia had no significant effect on blood $Na^+$ and serum creatinine. Blood $K^+$ significantly decreased from $3.1{\pm}0.5$(baseline) to $2.6{\pm}0.6mmol/l$($34^{\circ}C$) with the hypothermia for about 30 minutes, and significantly increased from $2.4{\pm}0.6$($25^{\circ}C$(S)) to $2.7{\pm}0.5mmol/l$($25^{\circ}C$(E)) with the hypothermia for 2 hrs. HCT significantly increased to $34^{\circ}C$, thereafter, continuously increased to $25^{\circ}C$(Start, End). PLT increased to $34^{\circ}C$, thereafter, continuously decreased to $25^{\circ}C$(Start, End). Also PLT decreased significantly from 414.3($30^{\circ}C$) to $308.8{\times}103/mm^3$($25^{\circ}C$, Start). Significant increases of blood glucose and L-lactate occurred between $30^{\circ}C$ and $25^{\circ}C$ (Start, End). Slight increase of serum BUN continuously appeared with the hypothermia. These results, such as characteristic changes of the significant decrease of pH and PLT at $34^{\circ}C$, the significant decrease of MAP at $30^{\circ}C$, and the significant increase of glucose and l-lactate at $30^{\circ}C$, suggest that homeostasis of rabbits to hypothermia rapidly decreases at $34{\sim}30^{\circ}C$ of rectal temperature. Therefore, we suggest that, during the period with the rapidly decreased homeostasis, the very carefully control and treatment need to recover hypothermic animals under the circumstances of the various hypothermic experiments and emergency medicine.