• Journal of Chest Surgery
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• v.24 no.7
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• pp.647-655
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• 1991

The efficacy of cold blood potassium cardioplegia during periods of ischemic arrest was assessed in 88 patients undergoing open heart surgical procedures at Chonnam National University Medical School from December, 1987 to January, 1989. The purpose of this study was to determine if the aortic cross clamping time[ACCT] over 120 minutes correlated with operative mortality, incidence of postoperative ventricular tachyarrhythmias, needs of postoperative inotropic support and serum enzyme levels. The patients were divided according to aortic cross clamping time[less than 120 minutes and 120 minutes or greater]. The results were as follows: 1. The operative mortality was 3.2% in ACCT<120min group and 7.7% in ACCT>120 min group. 2. The incidence of postoperative ventricular tachyarrhythmia was 1.6% in ACCT <120min group and 11.5% in ACCT>120min group[p<0.05]. 3. The incidence of postoperative inotropic support in congenital heart disease was 13.0Fo in ACCT<120min group and 45.0%o in ACCT>120min group[p<0.05]. The incidence in acquired heart disease was 26.0% in ACCT<120min group and 40.0% in ACCT> 120min group. 4. After cardiopulmonary bypass, serum GOT, LDH, CPK and CPK - MB were elevated prominently. Children showed higher value of the enzymes examined than adults did before and after cardiopulmonary bypass. In congenital heart diseases, postoperative serum GOT, LDH, CPK and CPK - MB levels of ACCT>120min group were significantly higher than those of ACCT<120min group. Postoperative serum GOT, LDH and CPK - MB levels of ACCT>=120min group were significantly higher than those of ACCT<120min group also in acquired heart diseases. The results suggest that the myocardial protective effect with cold blood potassium cardioplegic solutions was not sufficient when the aortic cross clamping time was over 120 minutes.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.225-233
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• 1989

Cardioplegia and myocardial protection were performed under cardiopulmonary bypass during open heart surgery with the use of St. Thomas Hospital cardioplegic solution [4 [C] for the coronary artery perfusion and normal saline solution [4[ c] for the topical cardiac cooling. To maintain the state of myocardial protection, coronary artery reperfusion was carried out using St. Thomas Hospital cardioplegic solution at the interval of 30 minutes. A total number of patients studied were 57 cases, including 37 cases of correction for congenital anomalies and 20 cases for acquired heart diseases. Cardiopulmonary bypass time during the surgery was observed to be average of 87.89*47.55 hours, aortic cross-clamping time [ACCT] to be average of 76.68*44.27 hours raging from 30 to 191 minutes. In order to evaluate the effects of myocardial protection in the surgery, serum enzyme levels were determined. To observe the relationship between ACCT and myocardial protection effects, patients studied were divided into the following 3 groups. I group: ACCT 60 minutes, II group: ACCT 90 minutes, III group: ACCT over 91 minutes [1] SGOT; The positive value [increased over 200 units] for ischemic myocardial injury during operation was observed in 11 cases [19.3% of the total] of the total patients studied, of which 4 cases [13.3%] in I group, 1 case [10.0%] in II group, and 6 cases [35.3%] in III group. [2] LDH; The positive value [increased over 900 units] for ischemic myocardial injury during operation was observed in 9 cases [15.7% of the total] of the total patients studied, of which 2 cases [6.6%] in I group, 1 case [10.0%] in II group and 6 cases [35.3%] in III group. [3] CPK; The positive value [increased over 800 units] for ischemic myocardial injury during operation was observed in 10 cases [17.5% of the total] of the total patients studied, including 4 cases [13.3%] in I group, 1 case [10.0%] in II group, and 5 cases [29.4%] in III group [4] The myocardial protection method used in the present study was demonstrated to be effective for the myocardial protection in the surgery with ACCT of up to 90 minutes. A few ischemic myocardial injury were observed in the surgery with ACCT over 91 minutes, but no significant cardiac dysfunction was noted. The surgery with ACCT of up to 191 minutes did not appear to give rise any significant interference with postoperative recovery.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.2
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• pp.29-34
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• 2012

Purpose : Presently, hardwares and softwares for reducing radiation exposure are continually developed for PET/CT examination. Purpose of this study is to evaluate effectiveness of reducing radiation exposure dose of CT and SUV changes of PET when applied each kernel to ACCT (Attenuation Correction Computed Tomography) according to adopted IRIS (Iterative Reconstruction in Image Space) software. Materials and Methods : Biograph mCT (Siemens, Germany) was used as a PET/CT scanner. Using AAPM CT performance phantom, from standard (120 kVp, 100 mAs), 7 scans were conducted by reducing 15 mAs each. After image reconstruction by FBP (Filtered Back Projection) and IRIS, noise and spatial resolution were evaluated. The same method was applied to anthropomorphic chest phantom and acquired images were compared. NEMA IEC body phantom was used for SUV evaluation. Injected dose rate for hot sphere (hot) and background cylinder (BKG) were 1:8. CT dose condition (120 kVp, 50 mAs) was the same for each scan and PET scan durations were 1, 2, 3 and 4min. After scanning, each kernel of IRIS was applied to ACCT. And PET images were reconstructed by ACCT adopted IRIS for comparing SUV changes. Results : AAPM phantom test for noise evaluation, SD for FBP 100 mAs, IRIS 55 mAs were 8.8 and 8.9. FBP 85 mAs, IRIS 40 mAs were 9.5 and 9.7. FBP 70 mAs, IRIS 25 mAs were 11.9 and 11.1. Above mAs condition for FBP and IRIS, SD showed similar values. And for spatial resolution test, there was no significant difference. For chest phantom test, when applied the same mAs and kernel to both of FBP and IRIS, every applied kernels showed reduced noise. Lower mAs and higher kernel value showed higher noise reduction. There was no considerable difference only except for I70 very sharp kernel for SUV comparison using NEMA IEC body phantom. Conclusion : In this study, low mAs (55 mAs) applied IRIS and standard mAs (100 mAs) applied FBP showed similar noise. And only except for I70 kernel, there was no significant SUV changes. It is possible to reduce needless radiation exposure and acquire better image quality than FBP's through applying appropriate kernel of IRIS to PET/CT.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.97-103
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• 2004

In general the starting current of single phase induction motor is 3 to 6times of the rated current It make flickering an electric lamp, dispersion a TV screen, insulation destructing an electric motor and momentary blazing of house wiring. Thus it happens losing an electric power loss and reducing an efficiency and a life of home electrical apparatus. In this paper, we proposed the method of reducing staring current with 3.7(%) using TRIAC and ACCT(alternated current transformer) in order to improve the above problem And also we verified semipermanent system with using semiconductor element.

• Journal of the Korean Society of Safety
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• v.34 no.2
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• pp.15-21
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• 2019

Recently, the number of facilities and users of zipline which is the most popular among extreme leisure facilities has been increasing year by year. Zipline is a means of transporting durable wire between two timber or stay and moving the trolley connected to the passenger at high speed in the opposite direction. However, due to the nature of the zip line facility, the risk of accidents is always present and safety accidents are frequently occurring. Therefore, this study investigates the current state of safety management and extract the problem in terms of safety management through analyzing the installation state of zipline facilities in the case of accidents and reviewing of similar facility regulations. In order to solve this problem, we will contribute to establishment of comprehensive and systematic countermeasures and establishment of safety improvement system by suggesting measures to improve safety management through analyzing foreign regulations and safety management regulations for zipline and other extreme leisure facilities.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.854-863
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• 1990

Since the open heart surgery was performed, various kinds of problem concerning the extracorporeal circulation[EGG] have been known. The author investigated the changes of serum potassium ion before and after ECC among the 102 patients including 63 adults and 39 children who underwent open heart surgery from April 19S6 to February 1990 in Chung-Ang University Hospital. The mean values of potassium ion before and after ECC were analyzed according to the influencing factors such as priming solution, aortic cross clamping time, the underlying disease, the type of oxygenator and the amount of cardioplegic solution. The results were as follows: l. In the aspect of congenital and acquired heart disease groups, the mean values of serum potassium ion[Mean\ulcornerS.D.] before and after ECC revealed a significant change only in the acquired heart disease group[congenital; 3.87$\pm$0.48mEq /L vs. 4.05$\pm$0.73mEq /L, P>0.05, acquired: 4.40 $\pm$0.98mEq /L vs. 4.11$\pm$0.52mEq /L, P<0.05]. Between the two groups, the changes of the mean values of serum potassium ion before and after ECC were significant[P<0.05]. But all values were within normal limits. 2. In the aspect of the aortic cross clamping time[ACCT], in the groups of less or more than 120 minutes, the mean values of serum potassium ion before and after ECC revealed no significant change[less than 120 min; 3.97+-0.64mEq /L vs. 3.99+0.67mEq /L, P>0.05, more than 120 min; 4.34+0.82mEq /L vs. 4.27+0.62mEq /L, P>0.05], and The changes of mean values of serum potassium ion between the two groups were not significant[P>0.05]. 3. In both membrane and bubble oxygenator groups, the mean values of serum potassium ion before and after ECC did not reveal a significant difference respectively [membrane; 4.74 +1.40mEq /L vs. 4.28+0.3lmEq /L, P>0.05, bubble; 4.02 +0.60mEq /L vs. 4.05 L0.68mEq/L, P>0.05], and no differences between the membrane and bubble oxygenator groups[P >0.05]. 4. In the groups of membrane and bubble oxygenator in the cases of ACCT more than 120 minutes, the mean values of serum potassium ion before and after ECC did not reveal a significant difference respectively[membrane; 4.36$\pm$0.85mEq /L vs. 4.37$\pm$0.26mEq /L, P>0.05, bubble; 4.30 $\pm$0.80mEq/L vs. 4.23$\pm$0.67mEq/L, P>0.05], and no differences between the two groups[P>0.05]. 5. In spite of increased amount of cold potassium cardioplegic solution, the mean values of serum potassium ion before ECC were similar to those of serum potassium ion after ECC[less than 20ml /kg

• Journal of Chest Surgery
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• v.33 no.7
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• pp.560-564
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• 2000

Background; Aprotinin, which is a nonspecific serine protease inhibitor, has an antiinflammatory and thrombogenic effect. However, it has an antithrombogenic effect during the cardiopulmonary bypass. This study was performed to evaluated the effects of aprotinin on the activated clotting time(ACT) and the total amount of the heparin used during the cardiopulmonary bypass. Marterial and Method; From December 1998 to November 1999, 82 consecutive patients electively underwent open heart surgery at Gachon medical school. The patients were older than 18 years. Eighty two patients were classified into a control group(group C, n=36) and a aprotinin-treated group(group A, n=46). Body weight, height, body surface area(BSA), pump time(PT), aortic cross clamping time(ACCT), and body temperature(BT) were determined. Total amount of heparin and protamine during the CPB were also measured. ACT was determined before heparin administration, at 20, 40 and 60 minutes after heparin administration, and after protamine administration. Result; No significant differences were noted in either group in body weight, height, BSA, BT, and the total amoun of heparin and protamine. Group A demonstrated a significant(p <0.05) increase in age, PT, ACCT, and ACT at 20, 40, and 60 minutes after heparin administration. Conclusion; In summary, the use of aprotinin prime resulted in an increase in ACT. The total amount of heparin in aproinin-treated patient was similar to that of the control group in spite of having the prolonged pump time. Therefore aprotinin may reduce the requirement of heparin.