• Journal of the Korean Institute of Gas
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• v.22 no.3
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• pp.38-44
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• 2018

Ammonia is used primarily as a refrigerant in refrigeration facility and SCR of a plant, and is frequently involved in leakage accidents. This study was conducted by selecting ammonia, a material with a wide influence range when evaluated, as a material with higher vapor pressure and lighter than air. In this study, the influence ranges were computed using KORA(Korea Off-site Risk Assessment supporting tool) with four different environmental factors : ground roughness, sealing, operating temperature, pressure, and leakage hole size. As a result, the difference in the influence range of ground roughness is approximately 4.62 times, while the ammonia storage tank shows a difference in the reduction rate of 0.64 when sealed. The extent of impact increased with increasing leakage depending on storage temperature and pressure, and when storing higher than the saturation vapor pressure, the impact range showed an average growth rate of 3.45 % per 0.1 Mpa($45^{\circ}C$). The influence ranges based on the size of the leakage holes is shown to be proportional to the area of the leakage zone.

• Journal of Veterinary Clinics
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• v.32 no.5
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• pp.399-403
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• 2015

Peritoneal dialysis (PD) is a treatment for renal failure and acute poisoning, and uses the patient's peritoneum in the abdomen as a membrane across which fluids and dissolved substances are exchanged from the blood. In this study, we evaluated the therapeutic efficacy and complications of automated peritoneal dialyzer (APD) in dogs with renal failure. PD was performed in 10 dogs using a swan neck catheter (Neonatal, Coviden) and automatic APD. The efficacy for each dog was assessed by calculating urea reduction ratio (URR) and creatinine reduction ratio (CRR). Mean concentrations of pre-dialysis creatinine and blood urea (BUN) were $7.09{\pm}3.84$ and $145.8{\pm}48.5$, respectively. The mean number of peritoneal dialysis cycles applied was $6{\pm}1$ cycles. Peritoneal dialysis resulted in a significant decrease in BUN concentration in 7/10 dogs, while a significant decrease in creatinine concentration in 9/10 dogs. The mean of URR was higher than that of CRR ($0.39{\pm}0.16$ vs $0.38{\pm}0.13$). The mean CRR and URR per dialysis cycles were $0.064{\pm}0.023$ and $0.065{\pm}0.023$, respectively. Complications found in this study were catheter occlusion, subcutaneous dialysate leakage, septic peritonitis, hypoalbuminemia and overhydration. This study found PD using a swan neck catheter and APD machine showed acceptable efficacy for successful peritoneal dialysis in dogs. However, close monitoring is required to minimize the risk of complication.

• Journal of Chest Surgery
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• v.42 no.3
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• pp.344-349
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• 2009

Background: The clinical history and physical findings of the patients with spontaneous pneumothorax depend largely on the extent of the collapse of the lung and the presence of pre-existing pulmonary disease. Large primary spontaneous pneumothorax is a possible serious condition and. so more active treatment will be necessary for these patients. The therapeutic guideline for large pneumothorax remains controversial. Therefore, by assessing the clinical results of surgical treatment for large primary pneumothorax, we aim to determine the indicators of treatment. Material and Method: Among 348 patients with primary spontaneous pneumothorax and who underwent surgical treatment from August 2004 through December 2007, 58 patients who responded to treatment for a large primary pneumothorax were included in the current study. We then retrospectively evaluated the operative findings and the surgical results. The patients with a pneumothorax of 80% or more, including those patients with tension pneumothorax, were considered to have a "large pneumothorax". Most of these patients Should be treated with a 12F chest tube. Thoracoscopic wedge resection was considered for treating recurrent pneumothorax, continuous air leakage, controlateral pneumothorax and first episode pneumothorax with visible blebs (> 1cm) seen on the computed tomography. Result: There were 50 men and 8 women with a mean age of 28.2 years (range: $14\sim54$ years). The mean length of hospitalization was 5.3 days (range: $2\sim10$ days). Nine patients underwent chest tube drainage only. Forty-nine patients underwent thoracoscopic wedge resection. The mean follow up time was 27.8 months (range: $10\sim58$ months). The actual site of air leakage could be located in 35 patients (71.4%) and this was correlated with pleural adhesion (p=0.005). The initial air leakage tended to be more correlated with intra-operative air leakage, although this was not statistically significant (p=0.066). The recurrence rate was 11.1 % for the patients with chest tube drainage and 2.0% for the patients with thoracoscopic wedge resection. Conclusion: Large primary pneumothorax requires an early diagnosis and early treatment. Thoracoscopic wedge resection may help to prevent recurrence of large primary pneumothorax.

• Journal of Chest Surgery
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• v.29 no.9
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• pp.964-970
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• 1996

One hundred eight patients (Feb.'86, through Jan.'96) underwent 53 mitral(MVR), 20 aortic(AVR), )5 double(DVR) valve replacement with SJM prosthesis. There were 55 males and 53 females whose mean age was 36.3 $\pm$ 10.4 years. We used 143 valves in mitral(88), aortic(54), and tricuspid(1) sites. The size and number of valves were 31 mm(32). 33inm(23), 29mm(20), 27mm(10), 25mm(2), and 35mm(1) in mitral site; 2)mm(21), 21mm(1 S), 19mm(7), 25mm(5), 27mm(2), and 33mm(1) in aortic site; and Blmm(1) in tricuspid site. Preoperative NYHA functional classes were II(14), III(73) and IV(21), and which were improved into I(89) and II(16) postoperatively. Early postoperative complications occurred in 15 cases(13.9%) in which LOS was the most common one(5 cases; 4.6%). fatly hospital death occurred in 3 cases(2.8%) due to LOS(1) and sudden cardiac arrest(2) he cummulative total follow-up period was 437.6 pl-yr with a mean of 4.1$\pm$2.9 years. There were 5 events of valve related'complications (2 TE, 1 paravalvular leak, 1 TE+paravalvular leak, 1 PVE) with the occurrence rate as 1.14%/pt-yr. Reoperation was performed in 2 cases and there were 2 cases of valve related death due to one PVE and one paravalvlllar leak. The complication free rate was 91.4$\pm$ ).4% at 10 years. Actuarial survival rate was 93.6 $\pm$ 3.1 % at 10 years.

• Journal of Chest Surgery
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• v.30 no.10
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• pp.973-978
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• 1997

We reviewed data of 64 patients who underwent reoperation because of prosthetic valve malfunction from January 1991 to December 1995. The indications for reoperation were prosthetic valve failure(primary tissue failure: 53 patients, 82.8%), prosthetic valve thrombosis(6 patients, 9.4%), paravalvular leak(3 patients, 4.7%), prosthetic valve endocarditis(2 patients, 3.6%). Prosthetic valve failure developed most frequently in mitral portion(40 patients, 75%), prosthetic valve thrombosis also in mitral portion(4 patients, 67%), paravalvular leak significantly in aortic portio (3 patients, 100%). Explant period was longest in prosthetic valve failure(mean 107.4 $\pm$ 24.6 months), shortest in prosthetic valve endocarditis with prosthetic valve thrombosis(1 patient, 1 month). Mean explant period, defined as from first valve replacement operation to redo-valve replacement operatopn, was 109.2$\pm$ 10.7 months in mitral portion, 97.8$\pm$ 10.4 months in aortic portion, 109.5$\pm$ 10.4 months in total. Overall hospital mortality was 9.38%. The most common cause of death was the low cardiac output(4 patients), other causes were bleeding(1 patient), CNS injury(1 patient). Preoperative NYHA class IV(P=0.011), emergency operation(P=0.011), prosthetic valve endocarditis(P=0.001) were the independent risk factors, but age, sex, explant period, ACC time, double valve replacement, valve position, second reoperation did not appear to be significant risk factors. Mean follow up period was 28.8 $\pm$ 17.8 months. Actuarial survival at 3 year was 92.0$\pm$6.2%, 2 year event-free survival w s 84.3$\pm$6.1%. We propose that patients undergoing reoperation because of prosthetic valve failure are carfully controlled and selected in regarding to above mentioned risk factors NYHA class IV, emergency operation, prosthetic valve endocarditis in preoperative state. About other risk factors possible, there is necessary of following study.

• Journal of Chest Surgery
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• v.33 no.7
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• pp.552-559
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• 2000

Background; The aim of this study is to evaluate our clinical experience with the Carbomedics heart valve prosthesis. Material and Method; Between Aug. 1988 and Dec. 1998, 294 Carbomidics valves were implanted in 235 patients(mitral; 143, mitral and aortic; 59, aortic; 33) The mean age at operation is 40.0$\pm$12.3 years(range 7 to 68 years); 63.8% (150patients) were woman. Follow up was 97.4% complete and mean follow up time was 5.7years with a total of 1209.2 patient-years. Result; The hospital mortality was 8.9%(mitral; was 95.2$\pm$1.6%(mitral ; 94.9$\pm$2.1%, mitral and aortic 95.0$\pm$3.7%, aortic 96.2$\pm$3.8%). Actual freedom rates from complications(linearized rates in parentheses) were fllowings; thromboembolism 96.2$\pm$1.5%(0.59%pt-yr), valve thrombosis 96.7$\pm$1.4%(0.5%/pt/yr), anticoagulant related hemorrhage 98.3$\pm$1.0%(0.25%/pt-yr), perivalvular leak 99.0$\pm$1.4%(0.5%/pt-yr), endocarditis 98.7$\pm$1.0%(0.25%/pt-yr), perivalvular leak 99.0$\pm$0.7%(0.17%pt-yr), endocarditis 98.7$\pm$1.0%(0.17%$\pm$pt-yr) and overall valve-related complications 88.9$\pm$2.5%(1.68%/pt-yr). Conclusion; The clinical performance of the Carbomedics valve was quite satisfactory with a low incidence of valve related mortality and morbidity.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.418-427
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• 2022

Our aim was to evaluate the quality of pine seeds after long-term storage and to analyze the correlation between germination and physiological characteristics. Therefore, we investigated the germination and physiological characteristics of seeds stored for different periods and storage temperatures. Pine seeds lost little viability and vigor after 12 years of storage at 4℃; it is even possible to prolong the storage period at -18℃. The deterioration process operating through long-term storage was characterized by a loss of seed vigor before a loss in seed viability. Electrical conductivity of the seed leachate was significantly higher in seeds that completely lost their viability, and was also found to be significantly correlated with the germination percentage, T50, mean germination time, and germination speed. Among the minerals leaked to the leachate, K had the highest concentration, followed by Na, Ca, Cu, Mg, and Fe, while Mn and Zn were not detected. Concentrations of K, Ca, Cu, Mg, and Fe in the leachate differed significantly by treatment, and in the cases of K, Ca, Cu, Na, and Mg, we observed large differences in the leachate between the seeds that were collected in 2003 and those collected in other years.. Germination percentage was significantly negatively correlated to the concentrations of Ca, Cu, K, Mg, and Na. The coefficient of uniformity of germination was significantly negatively correlated to Cu concentration. The other germination characteristics were not significantly correlated with the mineral concentration. Therefore, the mineral concentrations of pine seed leachate were not reliable indicators of seed deterioration when the differences in quality between seed lots were small. However, electrical conductivity could be an indicator of seed viability and vigor of pine seeds under long-term storage.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.149-154
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• 1998

We retrospectively analyzed 54 patients with esophageal cancer treated surgically between 1992 and 1996. They composed of 51(94.4%)men, 3(5.6%)women, and the age ranged from 42 to 78, the mean was 58.7$\pm$8.37. Symptoms were varied with dysphagia(72.2%), epigastric discomfort(16.6%), chest pain (5.6%), and so on(5.6%). Transthoracic esophagectomy(TTE) with esophagogastrostomy was done in 36 case, TTE with esophagocologastrostomy in 4 case, and transhiatal esophagectomy(THE) with esophagogastrostomy in 14 case. The operative mortality was 12.9%(7/54); 6 underwent TTE with esophagogastrostomy, and 1 underwent TTE with esophagocologastrostomy. Postoperative complications were of anastomotic leakage in 7 case, wound infection in 10 case, anastomotic stricture in 9 case, vocal cord paralysis in 2 case, bronchial tearing in 1 case, and pneumothorax in 3 case. Locations of esophageal cancer were upper thoracic esophagus in 4 case, middle thoracic esophagus in 34 case and lower thoracic esophagus in 16 case. Histological types were adenocarcinoma in 1 case and squamous cell carcinoma in 53 case. During the follow-up period, 25 cases died. Cumulative survival rate was 52.7% in 1 year, 45.5% in 2 year, 45.5% in 3 year, 45.5% in 4 year, 45.5% in 5 year.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.420-426
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• 1996

We previously reported 344 cases of esophageal reconstruction for caustic esophageal stricture between 1959 and 1982, and this is the second report of 69 cases during 12 year period from Jan. 1983 to Feb. 1995. There were 32 males and 37 females, ranging in age from 4 to 65 years(mean 36.4 years). Caustic materials were acid in 37 (53.7%) and alkali in 31 (44.9%). All cases underwent colon interposition without esophageal resection except 3 cases of cancer complication which were resected through thoracotomy. In 64 cases isoperistaltic right colon with teminal ileum interposition were performed, and 5 cases were interposed with left colon either isoperistaltic (2 cases) or antiperistaltic (3 cases) method. Anastomotic leakage was the most frequently encountered c mplication (14.4%, 10 cases), and they were 11.6%(8 cases) from cervical, 2.8% (2 cases) from ileocolostoma. Overall operative mortality was 2.9% (2169), main causes of death were sepsis due to graft necrosis and mediastinitis. During 6 months to 12years (mean 2.Syears) follow-up of survived 67 cases, 88.1% (59 cases) ate normally, 7.5% (5 cases) complained of moderate dysphagia (eating liquid diet), and 4.5% (3 cases) were unable to eat by mouth. In our experience, reconstruction of the esphagus with the colon is a satisfactory method that can be accomplished with acceptable morbidity and mortality. The right colon is a durable and functional esophageal substitute.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.393-402
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• 2006

The contamination characteristics of BTEX and TPH components in silty soils with the oil leakage event from point source were studied. The over ratios of three soil pollution standard for TPH component were $1.5{\sim}1.7$ times higher than that of BTEX component. The mean and maximum values of BTEX and TPH components with sample points were B-zone > A-zone > C-zone, and the highest concentrations were measured at $1{\sim}2m$ depth below surface. BTEX and TPH components were increased with linear distance in zone within 120 m and 80 m from point source. For the zone more than 120 m, BTEX and TPH concentrations were under soil pollution standard. The cutoff values of indicator kriging using BTEX and TPH components were defined as confirmative limit, warn- ing limit and counterplan limit. The variograms of indicator-transformed data were selected linear model. The contamination ranges of BTEX and TPH components using confirmative limit and warning limit were estimated similar, but the contamination range of those using counterplan limit was much reduced. The maximum contamination probabilities were estimated by probability maps usinB confirmative limit, warning limit and counterplan limit. The maximum contamination probabilities with three soil pollution standard were estimated 26%, 26% and 13% for BTEX component, and 44%, 38% and 26% for TPH component.