• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.3
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• pp.343-353
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• 1997

This paper presents a theoretical model for predicting transient behaviors during storage process of the cool storage system using the R141b clathrate. Introduction of the lumped capacitance method along with a brine reservoir having large thermal capacity yields a set of simplified energy equations. Based on the Arrhenius equation and the known experimental findings, the formation rate of clathrate for which the degree of subcooling is properly accounted is newly developed. An effective nondimensionalization of the model equations facilitates the closure of modeling as well as parametric study. Calculated results for a specific case not only simulate a typical pattern of temperautre variation in the tank successfully, but also agree reasonably well with available data. The effect of each characteristic parameter on the system performance is also investigated. It is revealed that the dominant among relevant parameters are the activation energy of reaction, the degree of subcoling and the initial mass fraction of refrigerant. Finally, the uncertainty associated with modeling of the shaft work variation appears to need further studies.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.7-12
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• 2016

This paper deals with a parametric study on cooling channel configurations to enhance the cooling effect. As a cooling effect has been increased, the exhaust gas by the plant from a manufacture is becoming deceased. To solve this problem, the design of a efficient cooling system is needed. In this paper, the cooling channel was analyzed to improve the cooling performance. The heat transfer rates depending on the number of baffle and the heiht of fin were obtained by using numerical simulation method. Three-dimensional Reynolds-averaged Naiver-Stokes equations were used to estimate flow and heat transfer in cooling channel, and the $k-{\varepsilon}$ model for turbulence closure was employed.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.364-367
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• 1999

Background: The efficacy of the hemostasis of prophylactic aprotinin after cardiac valve replacement was evaluated from January 1994 to December 1996 at Pusan National University Hospital. Material and Method: In a randomized study, 20 patients received aprotinin(2${\times}$106 KIU as a loading dose for 30 minutes after anesthesia, 1${\times}$106 KIU for priming and 5${\times}$105 KIU/hr as a maintenance dose from the completion of loading dose till skin closure) and another 20 untreated patients served as controls. Result: Aprotinin produced a significant reduction in postoperative blood loss compared with controls and significantly decreased total exposure to allogenic blood products compared with the control group(p<0.05). Conclusion: We conclude that aprotinin effectively reduces postoperative blood loss and trasfusion in patient undergoing cardiac valve replacement.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.147-152
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• 2017

The external reactor vessel cooling (ERVC) is well known strategy to mitigate a severe accident at which nuclear fuel inside the reactor vessel is molten. In order to compare the heat removal capacity of ERVC between the nuclear reactor designs quantitatively, numerical method is often used. However, the study for ERVC using computational fluid dynamics (CFD) is still quite scarce. As a validation study on the numerical prediction for ERVC using CFD, the subcooled boiling flow and natural circulation of coolant at the ULPU-V experiment was simulated. The commercially available CFD software ANSYS-CFX was used. Shear stress transport (SST) model and RPI model were used for turbulence closure and wall-boiling, respectively. The averaged flow velocities in the downcomer and the baffle entry under the reactor vessel lower plenum are in good agreement with the available experimental data and recent computational results. Steam generated from the heated wall condenses rapidly and coolant flows maintains single-phase flow until coolant boils again by flashing process due to the decrease of saturation temperature induced by higher elevation. Hence, the flow rate of coolant natural circulation does not vary significantly with the change of heat flux applied at the reactor vessel, which is also consistent with the previous literatures.

• Women's Health Nursing
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• v.14 no.1
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• pp.44-55
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• 2008

Purpose: This study was done to assess the personal experiences of the coping process during pregnancy for single mothers. Methods: The participants were 17 single mothers who had stayed in a social welfare facility. Data was collected with an in-depth unstructured interview. Data analysis was done by the grounded theory method. Results: One-hundred twelve concepts and 49 sub-categories were confirmed in the analysis. The sub-categories were grouped into 19 categories; escape from a miserable family, wrong meeting, openness of sex, defenseless state of pregnancy, inevitable result of pregnancy, heartbreak by herself, closure, isolation, difficult situation of being alone, stigma, supporting & protecting, helplessness, seeking, empowering, feeling of loss, conflict, facing issues, assuring a fresh start and becoming-mature. "Being driven over the edge of a cliff" was the key phenomenon which the single mothers experienced during the process of pregnancy. Conclusion: The above results will help nurses assessing single pregnancy mothers' needs and developing a nursing intervention program for supporting them. Therefore, nurses will be able to stop them from "being driven over the edge of cliff". A more vigorous nursing intervention is suggested for the research of the vulnerable classes of medical health care including single pregnant mothers.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.2
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• pp.100-106
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• 2013

There are many challenges for reconstruction after intraoral tumor resection. Especially, palatomaxillary reconstruction has two primary goals: closure of the oronasal communication and re-creation of proper myomucosal function. Prosthodontic treatment using obturator and several surgical procedures are selected depending on the size and site of the defect, the difficulty of operative procedure, operation time and donor site problem. Above all, it is considered that radial forearm free flap is the first choice for palatal reconstruction. Our department introduces a novel method using tunnelized-facial artery myomucosal island flap for palatomaxillary defect reconstruction, which can successfully reduce donor-site morbidity, and duration of surgery and hospitalization.

• Journal of Biomedical Engineering Research
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• v.13 no.2
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• pp.87-96
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• 1992

In thIns paper, a numerical simulation of steady laminar and turbulent flow in a two dimensional model for the total artificial heart is'presented. A trlleaflet polyurethane valve was simulated at the outflow orifice while the Inflow orifice had a trileaflet or a flap valve. The finite analytic numerical method was employed to obtain solutions to the governing equations in the Cartesian coordinates. The closure for turbulence model was achieved by employing the k-$\varepsilon$-E model. The SIMPLER algo rithm was used to solve the problem in primitive variables. The numerical solutions of the slulated model show that regions of relative stasis and trapped vortices were smaller within the ventricular chamber with the flap valve at the Inflow orifice than that with the trileaflet valve. The predicted Reynolds stresses distal to the inflow valve within the ventricular chamber were also found to be smaller wlth the flap valve than with the trlleaflet valve. These resu1ts also suggest a correlation be- tween high turbulent stresses and the presence of thrombus In the vicinity of the valves in the total artificial hearts. The computed velocity vectors and trubulent stresses were comparable with previ ously reported in vitro measurements in artificial heart chambers. Analysis of the numerical solo talons suggests that geometries similar to the flap valve(or a tilting disc valve) results in a better flow dynamics within the total artificial heart chamber compared to a trileaflet valve.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.223-228
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• 2008

Purpose: V.A.C. is a new concept which is closed dressing with negative pressure to promote wound healing. It has been widely used as the treatment of chronic and acute wounds such as pressure sores, burns, stasis ulcers, and other complicated wounds. However It has disadvantages such as high cost and the need of specific equipment. In this article, we described new method to overcome these disadvantages. Methods: We made newly innovated equipment with 50 cc syringe and spring to create negative pressure. From May 2006 to May 2007, we applied it to two patients with chronic wound. Results: The treatment period was 5 weeks for one case and 3 weeks for the other case. Both patients were healed completely without admission and wound healing was accelerated. During follow-ups, there were no complications. The mean cost for single dressing was 9,590 won. Conclusion: Modified portable negative therapy using newly innovated equipment could accelerate wound healing better than conventional dressing. It lowers the number of dressings, saves cost of treatment, and enables treatment as outpatient basis.

• Journal of Chest Surgery
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• v.30 no.1
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• pp.83-87
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• 1997

Taussig-Bing anomaly is infrequently associated with interrupted aortic arch and size discrepancy of great arteries makes it difficult to undergo arch reconstruction and arterial switch operation. A 20-day old male infant was admitted with the diagnosis of Taussig-Bing anomaly with type B Interrupted aortic arch. Multi-organ failure, due to the diminution of ductal flow, was stabilized after 3 weeks of prostaglandin El and controlled ventilatory support. The surgical correction consisted of VSD closure, arterial swtich and extended aortic arch reconstruction. The marked disparity between the hypoplastic ascending aorta and the dilated main pulmonary artery was overcome by constructing distal neoaorta using both native ascending and descending aortic tissue. The patient was extubated on postoperative 2nd day Postoperative catheterization showed no left ventricular outflow obstruction, no intracardiac shunt, and no incompetence of neoaortic valve.

• The Korean Fashion and Textile Research Journal
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• v.18 no.2
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• pp.194-206
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• 2016

This study analyzed jackets by Alexander McQueen that have always pleased customers with traditional tailoring via every season's collection. This study categorized and then analyzed jackets by components such as silhouette, jacket length, collar, lapel, sleeve, shoulder line, and closure methods. To achieve the research goal, the study referred to photographs of 501 jackets introduced in signature brand collections by Alexander McQueen between 1996 and 2010. The analysis results on McQueen's jackets with the general components of the clothes indicated that the frequency of traditional tailoring components (such as lapels, tight sleeves, natural shoulder lines, and a button closing method) was higher than the frequency of designs of dramatic, deconstructive patterns examined by previously-conducted research. This shows that Alexander McQueen was cognizant to the responsibilities as a tailor and the basics of tailoring when developing jacket designs. This study also confirmed how McQueen enjoyed adding exaggerated jacket design components by making various use of details that emphasize drastic shapes like the hourglass silhouette, wing collar (that covers the shoulders), peaked lapel collar, kimono sleeve, bell sleeve, crescent shoulder, and pagoda shoulder.