• Journal of the Korean Society for Precision Engineering
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• v.15 no.3
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• pp.18-23
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• 1998

This paper describes a research work of developing a computer-aided design of blanking and piercing for irregular-shaped sheet metal products. An approach to the CAD system is based on the knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of four main modules, which are input and shape treatment, flat pattern layout, production feasibility check, and strip layout module. Based on knowledge-based rules, the system is designed by considering several factors, such as radius and angle of bend. material and thickness of product, complexities of blank geometry and punch profile, and availability of press. This system is capable of unfolding a formed sheet metal part to give flat pattern and automatically account for the adjustment of bend allowances to match tooling requirements by checking the dimensions and relationships of parts of the folded product. Also this system can carry out a process planning which is obtained from results of irregular shape of product that was successful in production feasibility check module according to flat pattern layout and generate strip layout drawing in graphic forms. The developed system provides its efficiency for flat pattern layout, and strip layout for the irregularly shaped sheet metal products.

• Archives of Plastic Surgery
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• v.32 no.6
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• pp.753-756
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• 2005

In the cases of severe arrythmia and conduction failure, a permanent implanted pacemaker is considered an essential treatment modality with less complication rate, broad indications and low morbidity. However, some pacemakers needs to be removed or replaced due to infection, in need of a lead upgrade, elective replacement, conduction failure or insulation failure. The most common indication for pacemaker extraction is infection. Conservative treatments such as administration of intravenous antibiotics and limitation of debridement are not effective and the removal of the entire pacing system is considered to be the best approach to pacemaker pocket infection. Although a locking stylet, a laser sheath and other newer methods of transvenous lead extraction have been proven to be effective, all leads cannot be removed. Moreover, major complications such as, cardiac tamponade and respiratory arrest during leads extraction procedure should not be ignored. We experienced two cases of exposed pacemakers in the subclavicular region. After removing the pacemaker body, exposed proximal lead was pulled out and cut off. The end of remnant external insulation tube was tied to prevent infection propagation between external insulation tube and inner metalic coil. Wounds were covered by local flap coverage. No other problems were detected during the one-year follow-up. Since there are few reports on lead-preserving method of treating limited infection of exposed pacemakers, we would like to present our new method for treating exposed pacemakers.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.25-28
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• 2011

The virulence against the two-spotted spider mite, Tetranychus urticae Koch, was evaluated with entomopathogenic fungus Paecilomyces lilacinus (Thom) Samson HY-4 which is isolated from coleopteran insect and registered to Korean and US patents. Virulence tests were conducted with conidial suspensions ($1.5{\times}10^6conidia/ml$) of P. lilacinus HY-4 against T. urticae adults and positive results were recorded in laboratory conditions. The spraying device was also developed for the efficient and exact evaluation of treatment. The developed spraying device was named as SD-tower sprayer and its efficacy of spraying conidia was evaluated. The accumulated mortality caused by P. lilacinus HY-4 using SD-tower spray was about 73% at 6 days after inoculation. This suggest that the isolate P. lilacinus HY-4 may be considered as promising for a new approach to prevent adult infestations by T. urticae.

• Journal of Trauma and Injury
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• v.23 no.2
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• pp.175-179
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• 2010

Purpose: Sternal fractures after blunt thoracic trauma can cause significant pain and disability. They are relatively uncommon as a result of direct trauma to the sternum and open reduction is reserved for those with debilitating pain and fracture displacement. We reviewed consecutive 11 cases of open reduction and fixation of sternum and tried to find standard approach to the traumatic sternal fractures with severe displacement. Methods: From December 2008 to August 2010, the medical records of 11 patients who underwent surgical reduction and fixation of sternum for sternal fractures with severe displacement were reviewed. We investigated patients' characteristics, chest trauma, associated other injuries, type of open reduction and fixation, combined operations, preoerative ventilator support and postoperative complications. Results: The mean patient age was 59.3years (range, 41~79). The group comprised 6 male and 5 female subjects. Among 11 patients who underwent open reduction and fixation for sternal fracture with severe displacement, 6 cases had isolated sternal fractures and the other 5 patients had associated other injuries. Sternal fractures were caused by car accidents (9/11, 81.8%), falling down (1/11, 9.1%) and direct blunt trauma to the sternum (1/11, 9.1%), respectively. 3 of the 7 patients (42.9%) who underwent sternal plating with longitudinal plates showed loosening of fixation. Otherwise, none of the 4 patients who underwent surgical fixation using T-shaped plate had stable alignment of the fracture. Conclusion: Sternal fractures with severe displacement need to be repaired to prevent chronic pain, instability of the anterior chest wall, deformity of the sternum, and even kyphosis. In the present study, a T-shaped plate with a compression-tension mechanism constitutes the treatment of choice for displaced sternal fractures.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.210-217
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• 2018

Neuroinflammation is an immune response within the central nervous system against various proinflammatory stimuli. Abnormal activation of this response contributes to neurodegenerative diseases such as Parkinson disease, Alzheimer's disease, and Huntington disease. Therefore, pharmacologic modulation of abnormal neuroinflammation is thought to be a promising approach to amelioration of neurodegenerative diseases. In this study, we evaluated the synthetic flavone derivative 3',4'-dihydroxyflavone, investigating its anti-neuroinflammatory activity in BV2 microglial cells and in a mouse model. In BV2 microglial cells, 3',4'-dihydroxyflavone successfully inhibited production of chemokines such as nitric oxide and prostaglandin $E_2$ and proinflammatory cytokines such as tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 in BV2 microglia. It also inhibited phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor $(NF)-{\kappa}B$ activation. This indicates that the anti-inflammatory activities of 3',4'-dihydroxyflavone might be related to suppression of the proinflammatory MAPK and $NF-{\kappa}B$ signaling pathways. Similar anti-neuroinflammatory activities of the compound were observed in the mouse model. These findings suggest that 3',4'-dihydroxyflavone is a potential drug candidate for the treatment of microglia-related neuroinflammatory diseases.

• Journal of Chest Surgery
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• v.15 no.4
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• pp.432-439
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• 1982

Congenital posterolateral diaphragmatic hernia [Bochdalek hernia] is the result of a congenital diaphragmatic defect in the posterior costal part of the diaphragm in the region of the tenth and eleventh ribs. There is usually free communication between the thoracic and abdominal cavities. The defect is most commonly found on the left [90%], but may occurs on the right, where the liver often prevents detection. The male to female ratio is 2:1. Owing to the negative intrathoracic pressure, herniation of abdominal contents through the defects occurs, with resultant collapse of the lung. Shifting of mediastinum to the opposite side and compression of the opposite lung occurs. Most often these hernias are manifestated by acute respiratory distress in the newborn. A second, but less well recognized, group of patient with Bochdalek hernia survive beyond the neonatal period, usually present at a later time with "failure of thrive, intermittent vomiting, or progressive respiratory difficulty. " The diagnosis can often be made on clinical ground from the presence of respiratory distress, absence of breath sounds on the chest presence of bowel sounds over the chest . Roentgenogram of the chest confirm the diagnosis. Obstruction and strangulation have been reported but are rare. Treatment consists of early reliable identification of these congenital diaphragmatic hernia with high risk and surgical repairment. and postoperative pharmacological management with extracorporeal membranous oxygenation [=ECMO] support in the period of intensive care. On the surgical approach, for defects on left side, an abdominal incision is preferred, because of the high incidence of malrotation and obstructing duodenal bands. In the neonate, the operative mortality may be appreciable, but, later repair almost always is successful. During the period from 1972 to 1982, 4 cases of congenital Bochdalek hernia were experienced at the Kyung-Hee University Hospital.

• Journal of Chest Surgery
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• v.16 no.2
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• pp.190-198
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• 1983

The management of cardiac arrhythmias by cardiac pacing has increased greatly since the treatment of complete heart block with an external transcutaneous pacemaker in 1952, followed by the use of myocardial wires connected to an external pulse generation, by external transvenous pacing, and then by transvenous pacing with implantable components in thoracic wall.By now, the three bases of modern cardiac pacing for bradyarrhythmias had been established [1] an implantable device [2] the transvenous approach [3] the ability of the pacemaker to sense cardiac activity and modify its own function accordingly. In transvenous implantation of a pacemaker, any one of four vessels at the root of the neck is suitable for passage of the electrode - cephalic vein, external jugular vein, internal jugular vein, costo-axillary branch of the axillary vein. The new technique of direct puncture of the subclavian vein, either percutaneously or after skin incision only has been made, is invaluable & is used routinely. We have experienced one 25 years old patient who had rheumatic mitral stenosis & minimum aortic regurgitation with sinus bradycardia associated with premature atrial tachycardia & another 54 years old female patient who was suffered from sick sinus syndrome with sinus bradycardia & sinus arrest. The 1st patient was taken open mitral commissurotomy & aortic valvuloplasty and then was taken atrlal pace-maker implantation through If subclavian puncture method in post-op 14 days, and the second patient was taken atrial pacemaker implantation through If subclavian puncture method. Their postop course was in uneventful & were discharged, without complication. Their condition have been good to now.

• Journal of Chest Surgery
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• v.32 no.1
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• pp.27-31
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• 1999

Background: In spite of the development of chemotherapy, prognosis of metastatic lung cancer was poor. On the other hand, surgical intervention has proven itself to bring out superior results, therefore more operations are being praticed based on this superiority against chemotherapy and other modalities on metastatic lung cancer. Material and Method : We analyzed the surgical cases performed from 1983 to 1997 on 17 cases and estimated 5 year survival rate using Kaplan-Meier method. Result: Average age was 42.8, ratio between male and female was 10:7. We had 8 single lobe resections,3 pneumonectomies,1 wedge resection,2 bilobectomy and 3 cases of lobar resection with wedge resection. 5 deaths have occured and among the 5, 3 patients were caused by recurrence of ca. The remaining 12 patients are being followed up in OPD basis among these, 3 recurrence were observed and 9 are still free of cancer. The average survival time was 40.5 months and 5 year survival rate obtained through the Kaplan-Meier method was 60.4%. Conclusion: Even though we are a bit short of cases, we recommend that a thoracic surgeon approach this disease through a surgical method as possibly as he could.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.161-169
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• 2011

The objective of this study was to evaluate the efficiency of a modified filtration system treating non-point source (NPS) pollutants. The developed Best Management Practice (BMP) technology was designed based on the geographical and climatic characteristics of the site. A lab-scale test experiment was conducted using three different hydraulic loading rates representing the first flush flow, average flow and overflow conditions during a rainfall event. Water quality analysis was performed on the water samples taken at the inflow, outflow and infiltration during the test experiment of the lab-scale BMP. Also, the water and mass balance at different hydraulic loading rates was determined. Results from the lab-scale test experiment showed that the lab-scale BMP had a high removal efficiency of 80-90% for all NPS pollutants. The overflow test condition obtained the lowest removal efficiency among the hydraulic loading rates because it gave less opportunity for the pollutants to be filtered and retained inside system. The infiltration ratio was approximately 1 % of the inflow and outflow. Increasing the infiltration ratio requires technical approach of soil amendment where the BMP is installed.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.4
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• pp.13-22
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• 2007

The uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modeling system under uncertainty was described and demonstrated for use in watershed management and receiving-water quality prediction. A watershed model (HSPF), a receiving water quality model (WASP), and a wetland model (NPS-WET) were incorporated into an integrated modeling system (modified-BASINS) and applied to the Hwaseong Reservoir watershed. Reservoir water quality was predicted using the calibrated integrated modeling system, and the deterministic integrated modeling output was useful for estimating mean water quality given future watershed conditions and assessing the spatial distribution of pollutant loads. A Monte Carlo simulation was used to investigate the effect of various uncertainties on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorous (T-P) in the Hwaseong Reservoir, considering uncertainty, would be less than about 4.8 and 0.26 mg 4.8 and 0.26 mg $L^{-1}$, respectively, with 95% confidence. The effects of two watershed management practices, a wastewater treatment plant (WWTP) and a constructed wetland (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaseong Reservoir to less than 3.54 and 0.15 mg ${L^{-1}$, 26.7 and 42.9% improvements, respectively, with 95% confidence. Overall, the Monte Carlo simulation in the integrated modeling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on probability and level of risk, and its application is recommended.