• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.303-313
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• 2007

Various commercial catalysts used in chemical related applications have been disposed as an industrial waste when the catalytic activity of catalysts is not good enough to achieve an optimum yield. In addition, the amount of disposed three way catalysts (TWC) has been continuously increased. Considering the physicochemical, environmental, and economical characteristics, the deactivated spent catalysts can be treated in several alternative ways such as regeneration, recycling, and disposal. In view of the environmental and economical matters, the spent catalyst should be regenerated and used for the various purposes, although its activity is not as good as a fresh catalyst. On the other hand, spent catalysts containing noble and metal oxides can be applicable for the catalytic oxidation of volatile organic compounds (VOCs) by applying the proper treatment method. Therefore in this review the quantity of the spent catalysts and the available regeneration methods for the spent catalysts are briefly summarized and especially the proper regeneration method for applying the catalytic oxidation of VOCs and its results are introduced.

• 정보화사회
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• s.94
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• pp.40-46
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• 1995

CALS의 개념을 한마디로 정의하기에는 범위나 방법상 어려움이 있다. 그럼에도 불구하고 과거에는 군의 무기체계를 지원하는 개념에서 출발하였으므로 일반적으로 "무기체계의 설계, 제작 및 군수유통체계 지원을 위해 디지털기술의 통합과 정보공유를 통한 신속한 자료처리 환경 구축"으로 정의할 수 있었다. 그러나 이제는 "제품의 생산(생산계획 등 이전 활동 포함)으로 부터 폐기에 이르는 모든 활동을 디지털정보기술의 통합을 통해 구현하는 산업화전략"이라는 표현으로 바꾸어야 할 것이며, 이것은 곧 제품에 대한 요람에서 무덤까지의 총체적 관리를 위한 정보기술 통합전략이라고 정의할 수 있을 것이다.

• 정보화사회
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• s.93
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• pp.34-43
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• 1995

CALS의 개념을 한마디로 정의하기에는 범위나 방법상 어려움이 있다. 그럼에도 불구하고 과거에는 군의 무기체계를 지원하는 개념에서 출발하였으므로 일반적으로 "무기체계의 설계, 제작 및 군수유통체계 지원을 위해 디지털기술의 통합과 정보공유를 통한 신속한 자료처리 환경 구축"으로 정의할 수 있었다. 그러나 이제는 "제품의 생산(생산계획 등 이전 활동 포함)으로 부터 폐기에 이르는 모든 활동을 디지털정보기술의 통합을 통해 구현하는 산업화전략"이라는 표현으로 바꾸어야 할 것이며, 이것은 곧 제품에 대한 요람에서 무덤까지의 총체적 관리를 위한 정보기술 통합전략이라고 정의할 수 있을 것이다.

• Journal of Chest Surgery
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• v.27 no.2
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• pp.128-131
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• 1994

Recently we performed video-assisted thoracoscopic[VAT] examination and bullectomy under local anesthesia. Of the 10 patients undergoing VAT examination under local anesthesia with primary spontaneous pneumothorax, 8 patients underwent VAT bullectomy under local anesthesia using endo-GIA; 7 patients discharged within 24 hours after operation; 1 patient had an air leak after operation, so chemical pleurodesis with doxycycline was performed and discharged postoperative day 3. There have been no recurrence to date[60-120 days after operation]. We think spontaneous pneumothorax can be treated on an out-patient basis.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.824-828
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• 2010

The cause of primary spontaneous pneumothorax (PSP) is obvious. Recently, the FLCN mutation was suggested to be a causal factor in PSP. A 47-year-old Korean male patient with chief complaint of repetitive PSP had numerous emphysematous bullae and multiple large cysts based upon high resolution computer tomography. Here we report a case of PSP with an FLCN c.468_470delTTC mutation.

• Journal of Chest Surgery
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• v.24 no.2
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• pp.182-189
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• 1991

Fourteen patients underwent surgical resection of bullae between February, 1987 and June, 1990 via median sternotomy. Twelve patients had spontaneous pneumothorax with previous history of pneumothorax on the contralateral side or visible bullae on chest X-ray films. Two patients had bullous emphysema. The duration of operation and admission, frequency and amount of analgesic administered for pain control, pulmonary function test [FEV1, FVC, MVV] and the amount of bleedings were compared with six cases of staged unilateral thoracotomy. The results were as follows: 1. All patients were male. 2. Mean follow up period was 13.5 month and no recurrence of pneumothorax are noted after the operation. 3. Median sternotomy showed shortened admission days than thoracotomy. [12.4$\pm$2.7, 15.6$\pm$3.1 days] 4. Significantly shortened anesthetic time in median sternotomy than thoracotomy [121$\pm$21, 184$\pm$33 minutes] 5. Median sternotomy required less injection of analgesics than thoracotomy. [6.5$\pm$2.7, 13.5$\pm$3.1 ampules] 6. Bleeding amount and PFT showed no differences. 7. Complications were prolonged air leakage for more than 7 days [2 patients], transient elevation of SGOT and SGPT[2 patients], and wound infection[1 patient]

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.3
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• pp.3-9
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• 2002

When a flooding a lot of debris are drained from rivet. Drained debris separated lodgement debris and floating debris, and floating debris moving other region by wind and ocean current. This experimentation throw three buoys which installed with DGPS and other devices in nak-dong river, and check there location every minute. In consequence of this experimentation, floating debris drained nak-dong river are gathered near Dadaepo seaside or drifted Dong hae. Ocean current and wind driven current are largely influenced then tide. Numerical analysis calculated by MAPCNTR(develop by KRISO) is similar to the result of this experimentation.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1502-1507
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• 1992

Between February and July 1992, videothoracoscopic bullectomy was performed in nineteen patients with primary spontaneous pneumothorax. The indications of this surgery are recurrent in 12, persistent airleakage in 4 and previous contralateral pneumothorax in 3 patients. For the good operative field, we used double lumen endotracheal tube and put the CO2 gas into the thoracic cavity to make the lung collapse. We usually apply the endoGIA or electric cauterization for handling the bleb or bullae and there were 9 cases with of endoGIA only, 4 electric cauterization only and 6 both procedures. To evaluate the advantage of the Videothoracoscopic surgery, we compared surgical results with that of the tho-racotomy group[19 patients]. There were significant differences in operative time[93.8$\pm$41.9 min and 17.1$\pm$53.9 min, p< 0.01] and postoperative airleakage duration[35.6$\pm$113.3 hours and 117.9$\pm$214.4 hours, p<0.05] between the Videothoracoscopy and thoracotomy group. Tube indwelling time was shortened in Videothoracoscopy group[p<0.05]. The hospital stay was very short[p<0.01] and the patients needed analgesic injection less frequentley in videthoracoscopic group[p<0.05] In conclusion, we prefer the Videothoracoscopic procedure to the thoracotomy in uncomplicateed patients with pneumothorax because of simple procedure and good results.

• Journal of Chest Surgery
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• v.25 no.7
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• pp.763-768
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• 1992

To prevent recurrence of spontaneous pneumothorax, 23 patients were operated through median sternotomy for simultaneous resection of bilateral bullae, And 27 patients with spontaneous pneumothorax were treated with unilateral thoracotomy, We studied the number, duration and sites of recurrence including findings of CT scan, as well as comparing the both operated group. The incidence of spontaneous pneumothorax was 88% in patients with the ages between 16 to 35 Forty one patients[82%] were operated with the indication of recurrent pne-umpthorax. The number of pneumothorax attack was 2.34 per patient with recurrent pneumothorax. The 87.8% of recurrence was occured within 6 months from last attack. Ips-ilateral recurrnet pneumothorax was 56.1% and contallateral involve was 43.9%. The bilaterality of visible bullae was 90.9% in the findings of chest CT scan and 91.3% in the operative finding. The sensitivity and accuracy for bulla detection with chest CT were 92.6%, respectively. Exclude one case of complicated median sternotomy infection, the postoperative hospital stay was shorter in median sternotomy approached group[P<0.05]. In conclusion, the bullous lesions of the lung have tendency of bilaterality so that median sternotomy for simultaneous resection of bilateral bullae should be considered in patients with contralateral visible bullae with chest CT.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.724-728
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• 2008

Background: The purpose of this study was to identify factors associated with recurrent pneumothorax after wedge resection in primary spontaneous pneumothorax in our hospital. Material and Method: Two hundred thirty-five consecutive patient (98% males; mean age, $23.9{\pm}4.5$ years) who had undergone video-assisted thoracoscopic surgery (VATS) were reviewed retrospectively. The two groups were divided as follows: group A, non-recurrent patients (225 patients [96%]); and group B, recurrent group (10 patients [4%]); the risk factors were compared between the two groups. The single and multiple factors that influenced the recurrence rate were analyzed using Cox's proportional hazard model. Result: There were no significant differences between the recurrent and non-recurrent groups in terms of gender, smoking, site of recurrence, degree of collapse, operative time, and number or weight of resected bullae. The recurrence rate was significantly more common in the following: younger ages, increased height/weight ratio, longer initial air leakage period, and shorter duration of chest drainage. Early aggressive exercise (<30 days) of patients after wedge resection increased the tendency for recurrence. Conclusion: Thoracoscopic wedge resection does not have a higher recurrence rate than open thoracotomy. However, young age, height/weight ratio, continuous air, and duration of chest tube placement were risk factors for a recurrent pneumothorax.