• Journal of Chest Surgery
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• v.36 no.10
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• pp.759-765
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• 2003

Truncus arteriosus with interrupted aortic arch is a very rare congenital cardiac anomaly that has an unfavorable natural course. We report a successful one-stage repair of truncus arteriosus with interrupted aortic arch through median sternotomy in a 25-day-old neonate weighing 3.1 kg. We reconstructed the aortic arch with direct side-to-end anastomosis between ascending and descending aortas. The right ventricular outflow reconstruction was performed with untreated autologous pericardial conduit without valve following Lecompte maneuver. The patient has been grown-up in good condition (25 ∼ 50 percentile of body weight) and shows the right ventricular outflow tract wide 1 year after the operation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.3
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• pp.209-216
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• 2008

The application of focused ion beam (FIB) depends on the optimal interaction of the operation parameters between operating parameters which control beam and samples on the stage during the FIB deposition process. This deposition process was investigated systematically in C precursor gas. Under the fine beam conditions (30kV, 40nm beam size, etc), the effect of considered process parameters - dwell time, beam overlap, incident beam angle to tilted surface, minimum frame time and pattern size were investigated from deposition results by the design of experiment. For the process analysis, influence of the parameters on FIB-CVD process was examined with respect to dimensions and constructed shapes of single and multi- patterns. Throughout the single patterning process, optimal conditions were selected. Multi-patterning deposition were presented to show the effect of on-stage parameters. The analysis have provided the sequent beam scan method and the aspect-ratio had the most significant influence for the multi-patterning deposition in the FIB processing. The bitmapped scan method was more efficient than the one-by-one scan type method for obtaining high aspect-ratio (Width/Height > 1) patterns.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.6 no.3
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• pp.223-231
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• 2006

In high-speed fuzzy control systems applied to intelligent systems such as robot control, one of the most important problems is the improvement of the execution speed of the fuzzy inference. In particular, it is more important to have high-speed operations in the consequent part and the defuzzification stage. To improve the speedup of fuzzy controllers for intelligent systems, this paper presents an integer line mapping algorithm to convert [0, 1] real values of the fuzzy membership functions in the consequent part to a $400{\times}30$ grid of integer values. In addition, this paper presents a method of eliminating the unnecessary operations of the zero items in the defuzzification stage. With this representation, a center of gravity method can be implemented with only integer additions and one integer division. The proposed system is analyzed in the air conditioner control system for execution speed and COG, and applied to the truck backer-upper control system. The proposed system shows a significant increase in speed as compared with conventional methods with minimal error; simulations indicate a speedup of an order of magnitude. This system can be applied to real-time high-speed intelligent systems such as robot arm control.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.866-869
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• 2003

Less than 2% of patients with primary esophageal cancers have synchronous primary lung cancers and many patients with these synchronous tumors are deemed ineligible for radical resection by surgeons due to the poor prognoses of both the diseases. However, we believe that carefully selected patients could benefit from one stage curative resection for these synchronous tumors. We experienced a case of synchronous double cancer of the lung and esophagus and performed bilobectomy and Ivor Lewis operation simultaneously. To the best of our knowledge, this is the first report on the good result of one stage curative resection for these synchronous serious tumors in Korea.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.474-481
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• 1990

We have experienced 44 cases of coarctation of aorta in the age of infancy and children from April 1986 to September 1989 at Seoul National University Children`s hospital. Patients were thirty males and fourteen females, and their age ranged from one month to ten years[mean 23.84 $\pm$33.06 months] with thirty-two infant cases. In the infantile age, congestive heart failure was the most common chief complaint[18/32], and above that age, frequent upper respiratory infection was most common[8/12]. We experienced thirteen cases of isolated COA, twenty-two cases of COA with VSD, eight cases of COA with VSD, eight cases of COA with intracardiac complex anomalies and one case of COA with atrial septal defect. The associated intracardiac complex anomalies were three Taussig-Bing type double outlet right ventricle, one single ventricle, one transposition of great arteries, one atrioventricular septal defect, one hypoplastic aortic arch with left heart hypoplasia, and one Tetralogy of Fallot. Operative techniques of COA were twenty-three subclavian flap arterioplasty, 12 resection and end to end anastomosis, eight onlay patch angioplasty, and I direct angioplasty after resection of web. Among the cases with other cardiac anomalies, staged operation was done in twenty-nine patients, and single stage total correction was performed only in three patients. There were seven operative mortality[15.9%], all being in infantile age group, and among fourteen cases associated with large VSD[Qp/Qs>2.0, mean pulmonary arterial pressure>50mmHg], four patients were died, but there was no mortality in patients with small VSD. With above results, we are intended to discuss about the interval between staged operation, the fate of VSD after coarctoplasty in case of COA with VSD, causes of death, complications etc.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.503-508
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• 2007

Small scale D-water treatment plant(WTP) where has slow sand filtration was using raw water containing high concentration of manganese (> 2mg/l). The raw water was pre-chlorinated for oxidation of manganese and resulted in difficulty for filtration. Thus, sometimes manganese concentration and turbidity were over the water quality standard. Two stage rapid manganese sand filtration pilot plant which can treat $200m^3/d$ was operated to solve manganese problem in D-WTP. The removal rate of manganese and turbidity were about 38% and 84%, respectively without pH control of raw water. However, when pH of raw water was controlled to average 7.9 with NaOH solution, the removal rate of manganese and turbidity increased to 95.0% and 95.5%, respectively and the water quality of filtrate satisfied the water quality standard. Manganese content in sand was over 0.3mg/g which is Japan Water Association Guideline. The content in upper filter was 5~10 times more than that of middle and lower during an early operation but the content in middle and lower filter was increased more and more with increase of operation time. This result means that the oxidized manganese was adsorbed well in sand. Rapid manganese sand filter was backwashed periodically. The water quality of backwash wastewater was improved by sedimentation. Thus, turbidity and manganese concentration decreased from 29.4NTU to 3.09NTU and from 1.7mg/L to 0.26mg/L, respectively for one day. In Jar test of backwash wastewater with PAC(Poly-aluminum chloride), optimum dosage was 30mg/L. Because the turbidity of filtrate was high as 0.76NTU for early 5 minute after backwash, filter-to-waste should be used after backwash to prevent poor quality water.

• Journal of Gastric Cancer
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• v.1 no.1
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• pp.24-31
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• 2001

Purpose: Despite knowledge of the adverse effects of resection-line disease, surgeons continue to perform inadequate resections. This demonstrates the need for a more aggressive approach to assessment of resection margins at operation. Materials and Methods: Seven hundred fifteen gastric cancer patients who were operated on at our hospital from 1992 to 1998 were included in this analysis. Various clinicopathological factors, including resection-line involvement, were ascertained from the surgical and histopathological records. Results: Of the 715 evaluable patients, 27 patients ($3.8\%$) had involvement of one or both resection lines; in 10 patients the proximal resection line only, in 16 the distal resection line only, and 1 both resection lines were involved. Presence of resection-line involvement was significantly associated with T3 and T4 stage, N (+) stage, M (+) stage, type of operation (total gastrectomy), tumor location (entire stomach), size$\geq$11 cm), and gross type of tumor (Borrmann 4 type). When performing a distal subtotal gastrectomy, no involvement was found when the cranial and caudal distances between the lesion and the line of transection was equal to or greater than 2 cm and 3 cm, respectively, for early cancer and 7 cm and 3 cm, respectively, for advanced cancer. When performing a total gastrectomy for upper 1/3 or middle 1/3 gastric cancer, no involvement was found when the cranial distances between the lesion and the line of transection were equal to or greater than 3 cm and 4 cm, respectively, without distinction of the presence of serosal invasion. Conclusions: The difference in survival between positive and negative margin patients is limited to the group of patients with curative surgery. An important principle of treatment is that the entire tumor must be removed with a 3 cm distal margin and a 2- to 7 cm margin depending on the location and the depth of wall invasion of the tumor, to provide histologically negative margins.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.104-111
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• 2011

In order to assess the performance of co-digester using pig slurry and food waste at the farm scale biogas production facility, the anaerobic facility that adopts the one-stage CSTR of 5 $m^3\;day^{-1}$ input scale was designed and installed under the conditions of the OLR of 2.33 kg $m^3\;day^{-1}$ and HRT of 30 days in an pig farmhouse. Several operation parameters were monitored for assessment of the process performance. The anaerobic facility was operated in three stages to compare the performance of the anaerobic co-digester. In the Stage I, that was fed with a mix of pig slurry to food waste ratio of 7:3 in the input volume, where input TS content was 4.7 (${\pm}0.8$) %, and OLR was 0.837-1.668 kg-VS $m^3\;day^{-1}$. An average biogas yield observed was 252 $Nm^3\;day^{-1}$ with methane content 67.9%. This facility was capable of producing an electricity of 626 kWh $day^{-1}$ and a heat recovery of 689 Mcal day-1. In Stage II, that was fed with a mixture of pig slurry and food waste at the ratio of 6:4 in the input volume, where input TS content was 6.9 (${\pm}1.9$) %, and OLR was 1.220-3.524 kg-VS $m^3\;day^{-1}$. The TS content of digestate was increased to 3.0 (${\pm}0.3$) %. In Stage III, that was fed with only pig slurry, input TS content was 3.6 (${\pm}2.0$) %, and OLR was 0.182-2.187 kg-VS $m^3\;day^{-1}$. In stage III, TS and volatile solid contents in the input pig slurry were highly variable, and input VFAs and alkalinity values that affect the performance of anaerobic digester were also more variable and sensitive to the variation of input organic loading during the digester operation. The biogas produced in the stage III, ranged from 11.3 to 170.0 $m^3\;day^{-1}$, which was lower than 222.5-330.2 $m^3\;day^{-1}$ produced in the stage II.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.4
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• pp.429-436
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• 2008

Membrane system has been increasingly considered as a safe and cost-effective water treatment process especially in case of small scale water works. This research is a basis of membrane application in water works through a long period test with obtaining operation skills and evaluation of water quality and cost competitiveness. For the research, the UF membrane system was installed in small water treatment plant that uses river-bed water as raw water. The system was consisted of 2 stage membrane and operated in constant flow mode (Flux: 1.5, 1.0, 0.9, 0.6). In each different flux condition, TMP trends were showed better results at lower flux condition. And through the high flux condition test, it is certified that membrane system could deal with breakdown of one stage. Water quality of permeate was satisfied the water quality standards especially turbidity. To know what mainly causes fouling on membrane, the test by membrane with several cleaning agents and EDX analysis have done in lab. Through the tests, ferrous concentration in raw water, backwashing water and membrane surface etc. was high and it causes fouling inside and outside of membrane. So acid cleaning using organic acid such as oxalic acid is necessary in Chemical in Place (CIP). At the economical aspect the electrical cost of membrane system is higher than that of slow sand filtration but labor cost can be reduced by automation. However, the use of labor should be determined considering effectiveness and stability of operation. Because during the operation, there are several breakdown such as electrical shock by lightning, water drop in summer, etc.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.387-390
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• 2006

This paper presents a novel soft-switching PWM utility frequency AC to high frequency AC power conversion circuit Incorporating boost-half-bridge inverter topology, which is more suitable and acceptable for cost effective consumer induction heating applications. The operating principle and the operation modes are presented using the switching mode and the operating voltage and current waveforms. The performances of this high-frequency inverter using the latest IGBTs are illustrated, which includes high frequency power regulation and actual efficiency characteristics based on zero voltage soft switching (ZVS) operation ranges and the power dissipation as compared with those of the previously developed high-frequency inverter. In addition, a dual mode control scheme of this high frequency inverter based on asymmetrical pulse width modulation (PWM) and pulse density modulation (PDM) control scheme is discussed in this paper in order to extend the soft switching operation ranges and to improve the power conversion efficiency at the low power settings. The power converter practical effectiveness is substantially proved based on experimental results from practical design example.