• 대한두개안면성형외과학회지
• /
• 제21권4호
• /
• pp.253-256
• /
• 2020

Parotid gland plays the most critical role in saliva secretion in the oral cavity. Parotid gland injuries due to facial trauma can cause various complications such as formation of a fistula or sialocele. Thus, such saliva-related complications can interfere with wound healing and increase the risk of infection. Several previous studies have discussed the treatment of fistula or sialocele. Nonetheless, prevention of such complications is of utmost importance. We present a case of parotid gland injury due to trauma to the cheeks that was surgically treated, with early postoperative management involving oral administration of nortriptyline and closed drainage, without complications.

• 한국정밀공학회지
• /
• 제28권10호
• /
• pp.1196-1203
• /
• 2011

Statistical optimum methodology of table of orthogonal array, ANOM, ANOVA and RSM are applied to formulate optimum allocation design with design variables. It can be minimized average SPL of control volume, the objective function in closed system by optimal allocated positions of absorbing material. Structural natural frequency and acoustic natural frequency of cavity are analyzed by FEM and BEM in the closed system. Using BEM, average SPL of specific control volume is calculated according to the condition before using absorbing material and after using it. It is shown that noise is reduced by $5.02dB_{RMS}$ by absorbing material located at optimal position and minimum $1.83dB_{RMS}$ and maximum $3.47dB_{RMS}$ by the table of orthogonal array.

• Journal of Medicine and Life Science
• /
• 제17권1호
• /
• pp.16-20
• /
• 2020

Spontaneous hemopneumothorax is a rare disease, and it can cause life threatening condition. It is characterized by the accumulation of more than 400 mL of blood and air in the pleural cavity without any other apparent causes. A previously healthy 22-year-old female patient presented with acute chest pain and dyspnea. Chest X-ray and computed tomography revealed a massive hemopneumothorax in the left hemithorax. The images showed a completely collapsed left lung with right-sided tracheal deviation, several pleural adhesion bands, and fluid collection with air-fluid level. We emergently performed a closed thoracostomy, and then 560 mL of fresh bloods were initially drained. We considered an emergent video-assisted thoracoscopic surgery for pulmonary wedge resection and bleeding control because of the massive hemothorax. However, the patient's vital signs were stabilized after blood transfusion and supportive cares for re-expansion pulmonary edema. The patient discharged from the hospital on 11^th in-hospital day after removal of the chest tube, and there had not been any recurrence of the pneumothorax for 10 months. We suggest that treatment strategy should be decided upon individually based on the patient's condition and clinical course of the disease.

• 소성∙가공
• /
• 제22권4호
• /
• pp.183-188
• /
• 2013

Scroll compressors are widely used in air conditioning systems and in automobiles due to their low pressure loss, minimal vibrations, and light-weight. Open-die forging with back pressure is used to forge the rotating scroll, and it requires special care since the forging die can be severely damaged at the fixed end of the spiral cavity similar to a fracture of a cantilever beam. To overcome the inevitable weakness of the forging die due to such damage, an innovative design is necessary. In this study, structural analysis using the finite element method was conducted to determine the reason for the fracture of the forging die. A novel design to avoid stress concentrations and vertical deflection, causing serious damage to the die, is suggested.

• 한국주조공학회지
• /
• 제42권1호
• /
• pp.61-66
• /
• 2022

Hydraulic units are important components of agricultural and construction machinery, and thus require high-quality castings. However, gas defects occurring inside the sand cores of the castings due to the resin used is a problem. This study therefore aimed to develop a casting simulation method that can clarify the gas defect positions. Gas defects are thought to be caused by gas generated after the molten metal fills up the mold cavity. The gas constant is the most effective factor for simulating this gas generated from sand cores. It is calculated by gas generating temperature and analysis of composition in the inert gas atmosphere modified according to the mold filling conditions of molten metal. It is assumed that gases generated from the inside of castings remain if the following formula is established. [Time of occurrence of gas generation] + [Time of occurrence of gas floating] > [Time of occurrence of casting surface solidification] The possibility of gas defects is evaluated by the time of occurrence of gas generation and gas floating calculated using the gas constant. The residual position of generated gases is decided by the closed loops indicating the final solidification location in the casting simulation. The above procedure enables us to suggest suitable casting designs with zero gas defects, without the need to repeat casting tests.

• 한국수소및신에너지학회논문집
• /
• 제20권5호
• /
• pp.378-383
• /
• 2009

Hydrogen is the primary fuel in fuel cell systems. Because of high inflammation and explosion possibility of hydrogen, fuel cell systems require safety measures to prevent hydrogen hazard upon leakage. In this study, a model enclosure was made by referring to a commercial residential fuel cell system and hydrogen leakage experiments and computational simulations were conducted therein. Hydrogen was injected into the cavity through leakage holes located at the bottom while its flow rate was precisely controlled using MFC. The transient sensor signals from hydrogen sensors installed inside the enclosure were recorded and analyzed. The hydrogen sensor signals showed different delay times depending on their position relative to a leakage point, which indicated that hydrogen generally moves upward and accumulates at the upper region of a closed cavity. The inflammable regions with hydrogen concentration over 4% LEL were observed to locate near the leakage hole initially, and broaden towards the upper cavity region afterward. The simulation result showed that detection time at the hydrogen sensor was similar to the pattern of experimental results. However, the maximum concentration of hydrogen had a gap between experiment and simulation at detect point due to measurement errors and reaction rate.

• Journal of Chest Surgery
• /
• 제31권5호
• /
• pp.540-543
• /
• 1998

본 례는 65세 남자 환자에서 전폐절제술후에 발생한 기관지 늑막루 및 농흉의 치험례로 일차적으로 만성화하게한 다음 정중흉골절개하 심낭절개로 좌 주기관지를 노출후 자동봉합기(TA 4.8-30)로 좌 주기관지를 이중 결찰 봉합하여 좌측 늑막강내의 염증을 일으키는 원인인 기관지 늑막루를 차단한 다음, 늑막강내의 농흉을 치료함에 있어 흉강경을 이용하여 변형된 Clagett술식으로 내면을 깨끗하게 세척한 후 민감한 항생제를 이용하여 늑막강을 채우고 흉강삽관을 뽑고 그 부위를 봉합하는 방법을 시행하여 잔존 농흉강을 폐쇄하였다.

• 화훼연구
• /
• 제18권4호
• /
• pp.238-243
• /
• 2010

본 연구는 직삽 양액재배에 의한 '백마' 품종의 줄기공동화를 경감하고 절화품질 향상시키고자 양액 pH조정 비료종류와 에세폰 살포 효과를 알아보고자 실시하였다. 양액 pH조정 비료종류에 따른 pH 경시적 변화는 수산화칼륨 처리에서 pH 5.65에서 시작하여 큰 변화 없이 안정적으로 유지되었다. 화아분화기 이후 양액 pH조정 비료종류에 따른 절화장, 엽수, 절화중, 및 꽃잎수는 수산화칼륨 처리가 가장 좋았다. 중탄산칼륨처리는 경경이 두껍고 내벽이 두꺼워 동공의 크기와 면적이 가장 적었으나, 생육과 절화품질이 가장 좋은 수산화칼륨 처리구에서는 동공이 다소 큰 경향이었다. 화아분화기 이후 양액 pH조정에 따른 양분 흡수변화는 중탄산칼륨 처리는 전질소, 인산, 칼륨 및 칼슘의 흡수가 가장 적게 일어나 순환식 양액탱크내 잔류량이 가장 많은 반면 수산화칼륨의 경우 전질소, 인산, 칼륨 및 칼슘의 순환식 양액탱크내 잔류량이 적어 식물체내로 일정하게 흡수되도록 하여 생육 및 절화품질을 향상시킨 것으로 생각되었다. 에세폰 엽면 살포의 농도와 시기에 따른 생육은 관행(무처리)에 비해 500배 처리에서는 생육억제가, 1,000배와 2,000배 처리에서는 생육촉진 효과가 나타났다. 꽃잎수는 관행 302매에 비해 1,000배 개화 45일전 처리가 331개/송이로 가장 많게 나타났다. 에세폰 처리에 따른 줄기동공은 관행에 비해 2,000배 개화 30일전 처리가 크기 1.0 mm, 면적이 7% 정도 더 적은 것으로 나타났다. 따라서 국화 '백마' 양액 재배시 화아분화기 이후 수산화칼륨을 이용하여 양액 pH를 안정화시키고 에세폰 2,000배액을 개화 30일전 처리하여 줄기동공 크기를 감소시킴으로써 생육 및 절화품질향상을 도모할 수 있을 것으로 생각되었다.

• 대한치과의사협회지
• /
• 제15권1호
• /
• pp.27-31
• /
• 1977

Dentigerous cysts are closed epithelium-lined sacs formed about the crowns of unerupted teeth. Most of them probably are the result of degenerative changes in the reduced enamel epithelium. The authors observed 1 3 year old girl with a swelling and buccal bony expansion of the left mandible. Roentgen examination showed a cystic area in the left side of mandible. Under general anesthesia by means of nasotracheal intubation, intraorally, the operation by enucleation consisted in surgical removal of dentigerous cyst and the left unerupted Ist molar of mandible. The cavity was partially sutured and packed with iodoform gauze. Healing was uneventful.

• 대한수의학회지
• /
• 제42권3호
• /
• pp.393-396
• /
• 2002

A 5 kg, seven-month-old, female Pekingese dog was presented to Seoul National University Veterinary Medical Teaching Hospital with the history of anorexia and exercise intolerance. Muffled cardiac sound and mild abdominal pain were detected in the physical examination. In positive contrast peritoneography, contrast medium was observed in enlarged pericardial sac through the diaphragm. According to the history taking, physical examination and contrast radiographic study, the dog was diagnaosed congenital peritoneopericardial diaphragmatic hernia. Following midline celiotomy, herniated falciform ligament and greater omentum were repositioned to abdrminal cavity. The diaphragmatic defect was closed with absorbable suture. Clinical signs related to peritoneopericardial hernia disappeared immediately after surgical treatment. There had been no evidence of recurrence of the peritoneopericardial hernia for 1 year.