• Title/Summary/Keyword: Intermittent Operation

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A Study on 3-Dimensional Advection-Diffusion Model Operating Density Current Generator in Agriculture Lake (물순환장치 가동에 따른 농업용저수지의 3차원 이송확산모의에 관한 연구)

  • An, Jae-Soon;Lee, Young-Shin;Oh, Dae-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.3275-3284
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    • 2012
  • This study analyzed a 3D hydrodynamic advection diffusion using the EFDC model (Environmental Fluid Dynamics Code) in the agriculture lake to prevent stratification when we install a water circulator. EFDC model was predicted the range of the water circulator and various operational parameters ware derived for minimize the impact of the internal lake. Through EFDC simulation, water circulation is started overall circulation after 30days and a lake overall circulation showed that it was possible operated the water circulator after about 100days. Also, advection diffusion concentration was low in a lake when water circulator operate intermittent condition than continuous condition. And the entire circulation was stable in this condition. The S/B (Surface/Bottom) ratio can reduce the impact of lake as the surface water mixing a lot of. When the same condition (S/B ratio(3:1)), Case 8 (50days operation: 50days stop) of condition were able to minimize the impact of lake.

Intestinal Strangulation Associated with Pubic Fracture in a Dog (개에서 치골골절과 연관된 장폐색)

  • Lee, Jae-Il;Kim, Young-Suk;Jeong, Seong-Mok;Kim, Myung-Jin;Park, Chang-Sik;Kim, Myung-Cheol
    • Journal of Veterinary Clinics
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    • v.23 no.4
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    • pp.458-460
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    • 2006
  • A 2-year-old female, 3.8kg weight, mixed-breed dog was presented for a 10-day history of vomiting and anorexia. The dog was diagnosed with pelvic fracture by vehicular accident at a local animal hospital before 2 months, but fracture did not reconstructed. After 2 months, the dog suffered from intermittent vomiting and anorexia. On barium contrast, we diagnosed the dog as intestinal obstruction. Consequently, we were found obstruction by strangulation and adhesion of intestine at the fracture site through the operation. At present after 18 months of surgery, general physical condition of the dog is good.

Phosphorus Removal and Operating Performance of Mesh Filtration Bio-reactor with the Addition of Alum (Alum 주입 메쉬 침지 여과분리형 생물반응조의 운전 특성과 인 제거)

  • Jung, Yong-Jun;Min, Kyung-Sok
    • Journal of Korean Society on Water Environment
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    • v.21 no.5
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    • pp.458-463
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    • 2005
  • Considering the characteristics of a filtration bio-reactor equipped with a mesh filter module which can effectively maintain high concentration of biomass and enhanced solid-liquid separation performance, the hybrid process of filtration bio-reactor combined with coagulation was investigated to get improved filtration characteristics as well as water quality in this work. Two bio-reactors (Run-1 & Run-2) were operated under the following conditions: working volume of 25 L, continuous loading of a synthetic wastewater (BOD: 200 mg/L, T-N: 50 mg/L, T-P: 5 mg/L), where an appropriate amount of alum ($Al_2(SO_4)_3{\cdot}18H_2O$) was added once a day into the reactor (Run-2). In the system without using a alum (Run-1), the clogging of mesh filter module was observed two times through 85 days of whole operation. Meanwhile, the filter module did not clog even at higher MLSS concentration (6,000~12,000 mg/L) and the stable filtration (0.7 mid) was continued in the case of using a alum. Due to the stable formation of cake layers, BOD and SS were shown below 6 and 3 mg/L, respectively. T-P and pH of the effluent were changed because of the intermittent addition of the alum. In the case of Al/P=2.5, the average T-P removal efficiency per day was 85.2% and the average T-P concentration of the effluent was 0.3 mg/L. However, the removal efficiency of phosphate was influenced by pH in the reactor.

Double-outlet Right Ventricle with Pulmonary Stenosis [DORV: S.D.D.,subaortic VSD with ps]: One Operative case Report (양대혈관 우심실 기시증: 폐동맥협착 동반례의 수술 치험)

  • Kim, Hyeong-Muk;Lee, Nam-Su;Song, Yo-Jun
    • Journal of Chest Surgery
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    • v.10 no.1
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    • pp.148-155
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    • 1977
  • The clinical findings with cardioangiography and successful surgical treatment of a 10 year old girl with double-outlet right ventricle is reported at The Dept. of Thoracic and Cardiovascular Surgery, Korea University Hospital, College of Medicine. The patient has been suffered from intermittent cyanosis, palpitation, and exertional dyspnea since 1 year after NFSD, and a holosystolic ejection murmur of grade 4 at the left 3rd intercostal space with mild cyanosis of the lips was the only physical findings at the time of this admission. Cardiac catheterization revealed ventricular septal defect with left to right shunt of 43% and right to left shunt of 10.2%. On cardioangiography from the left ventricle revealed all of the left ventricular outflow shunted into the right ventricle through the large ventricular septal defect, and the aorta originated from the infundibular chamber of the right ventricle with left, anterior sided pulmonary artery. The atria, viscera, and ventricles were normally located, and right ventricular out-flow was narrowed with infundibular hypertrophy and pulmonary valvular stenosis. Surgical correction was accomplished by closure of the ventricular septal defect in such a way that left ventricular outflow was routed via a Teflon felt prosthetic tunnel to the aorta, and pulmonary valvulotomy with infundibulectomy Was done to pass Hegar`s dilator No. 15 for reconstruction of the right ventricular outflow tract. The patient tolerated complete repair and has continued to improve over a period of three months after operation with normal school life. Details of the disease and method of repair are presented with related references.

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A Study on Design and Performance of a Heat pipe for the Application to Solar Collector (태양열 집열기용 열파이프의 구조와 작동 특성에 관한 연구)

  • 임광빈;김철주
    • Journal of Energy Engineering
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    • v.2 no.2
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    • pp.179-186
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    • 1993
  • Heat pipes. applied to a flat plate solar collector, have a long and slender configuration with relatively low heat flux in the evaporator section. Such a heat pipe has a tendency to build-up a liquid pool at the lower part of the evaporator section. and at this pool occurs such complicated phenomena of evaporation and fluid dynamics as superheat, sudden generation of bubble, its likely explosive growth process and flooding, etc. In the present study. we tried to solve these problems by means of adjusting two principal design parameters, the liquid inventory and the installation region of the wick, using 4 heat pipes and 3 thermospheres. The corresponding results can be summarized as follows$\^$1)/. The effective thermal conductances of the heat pipe was greatly improved by eliminating the wick in the adiabatic and condenser sections$\^$2)/. The liquid inventory should be increased by about 40% larger than what is saturated the wick$\^$3)/. In the evaporator section the wick has a favorable effect to reduce both unstable operation by intermittent occurrence of nucleate boiling and response time at the initial start-up process.

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Rupture and Intrapleural Migration of a Cohesive Silicone Gel Implant after Augmentation Mammoplasty: A Case Report (코헤시브 실리콘 젤 유방삽입물을 이용한 유방확대술 후 발생한 유방삽입물의 흉강내로의 이탈 및 파열 증례보고)

  • Lee, Jun-Yong;Kim, Han-Koo;Kim, Woo-Seob;Park, Bo-Young;Bae, Tae-Hui;Choe, Ju-Won
    • Archives of Plastic Surgery
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    • v.38 no.3
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    • pp.323-325
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    • 2011
  • Purpose: Breast implant ruptures and displacement are problematic complications after augmentation mammoplasty. The authors report a patient whose cohesive silicone gel implant ruptured and migrated into the pleural cavity after augmentation mammoplasty. Methods: A 23-year-old female had received augmentation mammoplasty at a local clinic a week before visiting our hospital. When the patient's doctor performed a breast massage on the sixth postoperative day, the left breast became flattened. The doctor suspected a breast implant rupture and performed revision surgery. The implant, however, was not found in the submuscular pocket and no definite chest wall defect was found in the operative field. The doctor suspected implant migration into the pleural cavity, and after inserting a new breast implant, the doctor referred the patient to our hospital for further evaluation. The patient's vital signs were stable and she showed no specific symptoms except mild, intermittent pain in the left chest. A CT scan revealed the ruptured implant in the left pleural cavity and passive atelectasis. Results: The intrapleurally migrated ruptured implant was removed by video-assisted thoracic surgery (VATS). There were no adhesions but there was mild inflammation of the pleura. No definite laceration of the pleura was found. The patient was discharged on the first day after the operation without any complications. Conclusion: Surgeons should be aware that breast implants can rupture anytime and the injury to the chest wall, which may displace the breast implant into the pleural cavity, can happen during submuscular pocket dissection and implant insertion.

Congenital Esophageal Atresia and Tracheoesophageal Fistula: Report of Two Cases (선천성 식도폐쇄 및 기관식도루: 2례 보고)

  • 김형묵
    • Journal of Chest Surgery
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    • v.6 no.1
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    • pp.89-94
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    • 1973
  • Esophagel atresia and tracheoesophageal fistula may occur as separate entities but usually occur in combination. First described by Durston in 1670, esophageal atresia was not successfully treated until 1939 when Ladd in Boston and Leven in St. Paul obtained the first survivors utilizing the methods of gastrostomy, esophagostomy and extrapleural ligation of the tracheoesophageal fistula as multiple operations which required months of hospitalization. Two years later Cameron Haight performed the first successful primary repair and afterward about 2000 cases of esophageal atresia with distal tracheoesophageal fistula reported in the world. In Korea, there appeared about 27 cases in the literature and 8 successful repaired cases noted in these year. Anther report two cases of esophageal atresia, of which one case was successfully treated with Haight`s method. Case 1.: Normal full term delivered boy with chief complaints of respiratory difficulty and persistent drooling with chocking, 3. lkg, was admitted with emergency 5 hours after delivery. Physical findings revealed no specific abnormal signs except distended abdomen and grunting respiration. Esophagograrn and bronchogram revealed proximal esophageal atresia and distal tracheoesophageal fistula proximal to the carina. Parent refused operative therapy and patient died 24 hours after discharge. Case 2. :3. lkg. normal full term delivered girl was admitted 4 days after delivery with chief complaints of regurgitation after feeding, chocking, cyanotic spell and fever since the day after delivery. Physical examination revealed persistent drooling, grunting respiration, and fever with moderate dehydration. Tracheoesophageal suction and fluid therapy with antibiotics improved her condition and subsided ]pneumonic condition. Esophagogram revealed markedly dilated proximal esophagus as blind loop and stomach distended with gas, and repairing operation as Haight`s method was performed on the 7th day after delivery. Patient tolerated all the operative procedure well and recovered uneventfully. Esophagogram on the 7th postoperative day showed passage of the lipiodol through the anastomotic side with moderate stricture,and feeding permitted. Patient tolerated all the feeding amount well and discharged on the 11th postoperative day. Followup revealed intermittent regurgitation after feeding and corrected with bougination.

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Chondromyxoid Fibroma of the Rib Report of one case - (늑골에 발생한 연골점액유사 섬유종 -1예 보고-)

  • Lee, Jae-Wook;Lim, Jae-Ung;Won, Yong-Soon;Kor, Eun-Suk;Shin, Hwa-Kyun
    • Journal of Chest Surgery
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    • v.38 no.11 s.256
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    • pp.788-790
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    • 2005
  • Chondromyxoid fbroma (CMF) is a rare, benign tumor of the bone that represents fewer than $2\%$ of all benign tumors of bone. CMF is most often found in the long tubular bones, especially the tibia and femur near the knee joint. Less common sites included the pelvis, fibula, calcaneus and rib. A 54-year-old male patient presented to us with history of swelling and mild, intermittent local pain without any rise in overlying skin temperature in lateral portion of left 7th rib for one-month duration, which was diagnosed as benign rib tumor by plain chest X-ray and CT scan, and treated successfully by excision of rib with good result. Pathologic diagnosis of this tumor was CMF. Without any medical therapy, there was no evidence of recurrence after operation. We report this case and follow-up of the patient.

Atherosclerotic Aneurysm of the Right Proximal Subclavian Artery - A case report - (우측 근위부 쇄골하동맥에 발생한 동맥경화성 동맥류 - 1예 보고 -)

  • Kim, Duk-Sil;Kim, Sung-Wan;Kim, Byung-Ki;Lee, Hyeon-Jae;Lee, Gun;Lim, Chang-Young
    • Journal of Chest Surgery
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    • v.42 no.5
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    • pp.649-652
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    • 2009
  • A 75-year-old man presented with worsening dyspnea and intermittent dysphagia of one month's duration. A plain chest X-ray showed severe tracheal indentation by the right superior mediastinal mass. A chest CT established the diagnosis of a saccular aneurysm arising from the right proximal subclavian artery. Resection of the aneurysm and arterial revascularization was done through a median sternotomy with supraclavicular extension. Aneurysm wall and thrombus culture results were negative and pathology showed an atherosclerotic aneurysm. After the operation, dyspnea and dysphagia were reduced, but he died of advanced stomach cancer 8 months later.

Development of Three-dimensional Thermo-fluid Numerical Model for Steam Drum of a Basic Oxygen Furnace (순산소 전로의 증기드럼 내의 3차원 열 유동 해석모델 개발)

  • Jeong, Soo-Jin;Moon, Seong-Joon;Jang, Won-Joon;Kho, Suntak;Kwak, Hotaek
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.479-486
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    • 2016
  • The efficient steam drum should be required to reduce carbon oxide emissions and heat recovery in oxygen converter hood system. However, steam generation is limited to the time of the oxygen blowing period, which is intermittent or cyclical in operation of steel-making process. Thus, steam drum should be optimized for an effective steam generation during the oxygen blowing portion of the converter cycle. In this study, a three-dimensional computational fluid dynamics (CFD) model has been developed to describe the impacts of changing various operating conditions and geometric shape on thermo-fluid characteristics and performance of the steam drum. This model encompasses not only fluid flow and heat transfer but also evaporation and condensation at the interfacial surface in the steam drum by using VOF (Volume of Fluid) method. To validate the prediction performance of this model, comparison of the steam flow rate between numerical and experimental result has been performed, resulting in the accuracy of the relative error by less than 3.2%.