• Journal of Chest Surgery
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• 제10권1호
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• pp.7-17
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• 1977

The increasing frequency of post-tracheostomy stenosis parallels the increase in the incidence of tracheostomy. The development of stenosis of trachea following the operation of tracheal tumor or tracheostomy is a very serious complication. The continuing need for an adequate tracheal substitute has not been answered, despite the necessities of excision and reconstruction of the trachea to keep for effective ventilation. Experimental tracheal reconstuction, with a prosthesis of heavy Marlex mesh and pericardium, _ vas performed in twelve dogs. Five to six tracheal ring circumferential defects were created and were bridged with heavy Marlex mesh fashioned into a tube of suitable diameter. Group A: A prepared cylinder of Marlex mesh was anastomosed outside the cut ends of the trachea. Group B: The external surface of the prepared cylinder of Marlex mesh was completely covered with suitably sized patch of pericardium and overlapped all margin of the Marlex mesh by 2 to 3 mm in each direction. Group C: The internal surface of the prepared cylinder of Marlex mesh was covered with suitably sized patch of pericardium and overlapped all margin of the Marlex mesh by 2 to 3 mm in each direction. The results of this exepriment were as follow: 1. In group A and B, the graft was well bridged with new granulation and fibrous tissue, and the lumen of trachea kept good patency for effective ventilation.. The interstices of Marlex became uniformly infiltrated with young well vasculated connective tissue. Epithelization has not yet occurred at 4 weeks in each group, but there were evidences of new growing mucosa at grafted site in 6 weeks. The remainder of the prosthesis was completely covered with glistening epithelium and the underlying fibrous tissue became more matured with little inflammation. These findings were more striking in group B than group A. 2. In group C, the covered pericardium was necrotized with stenosis of the lumen of grafted site due to poor blood supply.

• Advances in pediatric surgery
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• 제7권1호
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• pp.21-25
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• 2001

Congenital diaphragmatic hernia (CDH) in the past was considered a surgical emergency requiring immediate operation. Several groups now advocate preoperative stabilization and delayed surgery. The treatment strategy for CDH in this institution is delayed surgery after preoperative stabilization. The aim of this study was to evaluate the results of delayed surgery. A retrospective review of 16 neonates with CDH was performed. Surfactant. conventional mechanical ventilation. high frequency oscillation. and nitric oxide were utilized for preoperative stabilization as necessary. The difference in outcome between two groups differentiated by the duration of the preoperative stabilization periods with mechanical ventilation (${\leq}$ 8 hours and > 8 hours) was determined. Chi-square test was used to analyze the data. There were 7 right-sided hernias and 9 left. The average duration of stabilization was 32.4 hours. Hepatic herniation through the defect was found in 6 cases and all died. The most common postoperative complication was pneumothorax. The mortality rate of the right side hernia was higher than the left (85.7% vs. 33.3%. p=0.036). Mortality rate of the group (N=8) whose preoperative stabilization period was 8 hours or less was better than that (N=6) whose preoperative stabilization period was more than 8 hours (25.0% vs. 83.3%. p=0.031). The overall mortality rate was 56.3%. The better prognosis was noticed in left side hernia. no liver herniation, or shorter preoperative stabilization period.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.378-384
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• 2008

This Paper presents dynamic analysis of HVAC(Heating Ventilation & Air Condition) Heater Case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC Heater Case. finite element model which consists of shell elements is constructed for modal analysis and experimental Modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model After identifying node shape and natural frequency of HVAC Heater Case, local stiffness of HVAC Case is evaluated through point mobility using finite element analysis and experiment.

• 한국유체기계학회 논문집
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• 제13권2호
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• pp.18-23
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• 2010

This paper presents a procedure for the aerodynamic and aeroacoustic characteristics of a sirocco fan. For the aerodynamic and aeroacoustic analyses of the sirocco fan, three-dimensional steady and unsteady Reynolds-averaged Navier-Stokes equations are solved with a shear stress transport turbulence model for turbulence closure. The flow analyses were performed on a hexahedral grid using a finite-volume solver. The validation of the numerical results is performed by comparing with experimental data for the pressure, efficiency and power. The internal flow analyses of the sirocco fan are performed to understand the unstable flow phenomenon on the casing for the wall pressure and internal flow characteristics at each position. It was found that fluctuation of pressure and locally concentrated noise source are observed near the cut-off and expansion regions of the casing.

• Journal of Yeungnam Medical Science
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• 제24권2호
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• pp.97-106
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• 2007

Functional electrical stimulation (FES) has developed over the last 35 years to become a scientifically, technologically and clinically recognized field of interest in clinical medicine. FES has been applied to locomotion, grasping, ventilation, incontinence, and decubitus healing. However, all of these achievements illustrate the initial applications of FES; its true potential has not yet been realized. Recently, FES systems, which are miniaturized stimulation devices, have been utilized in the clinical setting. However, because the stimulating electrodes of the current FES devices are percutaneous electrodes, which are susceptible to wire breakage, and skin infection an implantable FES stimulating electrode has been introduced in the U.S. and Japan. In the present study, an external power supply method using radio frequency (RF) coupling and data transmission was developed for the control of the implantable FES device. In addition, we review the current understanding of FES devices and their application in clinical medicine.

• 중환자간호학회지
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• 제2권1호
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• pp.15-25
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• 2009

Purpose: This study investigated the effects of chest physiotherapies on intensive care unit patients mechanical ventilated. Methods: Good lung down position, chest percussion, postural drainage was applied to patients who admitted to ICU. Each patients divided into four groups and each group received different treatments. Sputum amount, lung compliance, tidal volume and oxygen saturation were measured before treatment and immediately, and time flowing. Data was analyzed with frequency, percentage, ANOVA and paired t-test using via SPSSWIN 12.0 program. Results: There were significant differences in variables each characteristics of subjects. Chest percussion increased tidal volume, static lung compliance for the mean time. Desaturation related to suction. Conclusion: Chest percussion influences on lung compliance. Based on this study results and limitation, this study suggests repeated studies in various groups

• 한국의류학회지
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• 제28권3_4호
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• pp.403-413
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• 2004

The purpose of this study was to investigate to wearing practices and consumer needs for stockings. 503 subjects were surveyed in 2002. Data were analyzed by frequency, $\chi$$^2$, ANONA(LSD) and factor analysis. The results were as follows; 1) Many subjects considered the colors, but a very few of them considered the components and handling signs when purchase their stockings. These tendencies show meaningful differences according to their ages, jobs and the status of whether they are married or single. The wearing rates of stockings show differences according to their physical characteristics and social demographical variables. 2) They demand that the exact fiber contents and the mixture ratios which the stockings have should be indicated, and also want the sizes of the stockings to be indicated by three steps according to their body sizes, and they ask that the stockings have more various colors. They required that the stockings should have good ventilation, durability, warmth-keeping, hygroscopicity and elasticity in leg parts, and anti static electricity or bacteria.

• 한국소음진동공학회논문집
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• 제19권1호
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• pp.101-108
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• 2009

This paper presents dynamic analysis of HVAC(heating ventilation & air conditioning) heater case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC heater case, finite element model which consists of shell elements is constructed for modal analysis and experimental modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model. After identifying mode shape and natural frequency of HVAC heater case, local stiffness of HVAC case is evaluated through point mobility using finite element analysis and experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1012-1013
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• 2006

Marine technology must advance to meet the needs of a wealthier and more demanding public while at the same time provide greater environmental protection. Pollution noise and vibration is the specific issue being discussed in this paper Noise is of course due to vibration from high speed engines driving generators, entilators, winch and other gear, while underwater noise pollution results from the propellers and the resistance produced by the hull of the ship moving through the water. Vibration is also a factor in potential damage to sensitive electronic gear and metal fatigue. The issue of noise pollution does not cease when a vessel enters her berth and the main engines shut down. There is still the matter of ventilation and other mechanical factors at work to maintain a comfortable, efficient environment. We measured the noise level and vibration displacement in the training ship A-Ra at underway and Berth. The authors analyzed the frequency of noise and maximum vibration displacement in the position.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2008년도 춘계학술대회
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• pp.11-18
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• 2008

This research modified the checklist used in the universities in USA, England and Korea considering the current situation of Korea, and conducted case studies upon each section of appointed chemical laboratories based on 4M criteria, which stands for Machine, Media, Man and Management. The purpose of the studies is to assess how dangerous the laboratories are and to contribute to prevention of accidentsin the laboratories as well as reducing loss of lives and property. The result of this research found out the harmful and hazardous factors based on the 4M-type checklist and predicted the dangerousness as it multiplies possible frequency by intensity. Protective equipment, safety facilities in laboratories, emergency exit and compressed gas cylinder are found to be more dangerous, so the result shows that it is desirable to improve ventilation, safety facilities and circumstances of the laboratory through the investment.