• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.76-88
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• 2003

This study exploits the robot system which is necessary in gene study, bio-technology industry. As well, it can achieve the job of DNA chip manufacturing whose use rate has been increased recently. The robot consists of DNA spotting device for spotting DNA on the silylated slide and well plate, bed for fixing well-plate, washing & drying device of washing and drying the pin part of DNA spotting device, distillation-water vessel, and discharge vessel of wash water. We made the term of sticking DNA to the pin on well plate to be 15 seconds. The spot size of DNA was set to be 0.28 mm on the average by bringing the slide into contact with pin for 1 second. At this rate, if DNA is spotted in the minimum space possible of about 0.32mm, it can stick about 8,100 DNA spots on the well plate. Analyzing the procedure: Movement starts. Pin washes, dries, and smears DNA on the well plate. Spots DNA onto 12 chips takes 2 minutes and 50 seconds.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.412-412
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• 2009

Carbon-based nano materials have a significant effect on various fields such as physics, chemistry and material science. Therefore carbon nano materials have been investigated by many scientists and engineers. Especially, since graphene, 2-dimemsonal carbon nanostructure, was experimentally discovered graphene has been tremendously attracted by both theoretical and experimental groups due to their extraordinary electrical, chemical and mechanical properties. Electrical conductivity of graphene is about ten times to that of silicon-based material and independent of temperature. At the same time silicon-based semiconductors encountered to limitation in size reduction, graphene is a strong candidate substituting for silicon-based semiconductor. But there are many limitations on fabricating large-scale graphene sheets (GS) without any defect and controlling chirality of edges. Many scientists applied micromechanical cleavage method from graphite and a SiC decomposition method to the fabrication of GS. However these methods are on the basic stage and have many drawbacks. Thereupon, our group fabricated GS through Thermo-electrical Pulse Induced Evaporation (TPIE) motivated by arc-discharge and field ion microscopy. This method is based on interaction of electrical pulse evaporation and thermal evaporation and is useful to produce not only graphene but also various carbon-based nanostructures with feeble pulse and at low temperature. On fabricating GS procedure, we could recognize distinguishable conditions (electrical pulse, temperature, etc.) to form a variety of carbon nanostructures. In this presentation, we will show the structural properties of OS by synthesized TPIE. Transmission Electron Microscopy (TEM) and Optical Microscopy (OM) observations were performed to view structural characteristics such as crystallinity. Moreover, we confirmed number of layers of GS by Atomic Force Microscopy (AFM) and Raman spectroscopy. Also, we used a probe station, in order to measure the electrical properties such as sheet resistance, resistivity, mobility of OS. We believe our method (TPIE) is a powerful bottom-up approach to synthesize and modify carbon-based nanostructures.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.702-708
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• 1999

Background: Surgical closure of the PDA in premature infants with complications or contraindications to indomethacin use, or recurrence of symptomatic PDA is a safe and effective procedure with low operative risk and minimal complications. Material and Method: From April 1996 to August 1998, 11 premature infants with body weight under 1.5 kg at operation underwent operation for a symptomatic PDA (male:5, female: 6). Associated dise ases were congenital heart disease(7), hyaline membrane disease(6), intraventricular hemor rhage(4), pneumonia(4), pneumothorax(3), hyperbilirubinemia(2), necrotizing enterocolitis(2), renal failure(1), epilepsy(1), and hydrocephalus(1). Surgical techniques are hemoclipping(8) and ligation(3). The size of PDA was 3~6 mm (5.0$\pm$1.2). Result: Systolic and diastolic blood pressure rised and heart rates decreased after PDA closure. ABGA improved postoperatively. There were no surgical complications. Six infants with improved ABGA data were weaned from mechanical ventilatory support. The follow-up durations after discharge were 3 month to 12 month. Five deaths were not related to operation. The causes of death were hyaline membrane disease(2), bronchopulmonary dysplasia with pneumonia(1), sepsis(1), and con gestive heart failure with respiratory distress syndrome(1). Conclusion: Early operative closure is the treatment of choice in most premature infants with a hemodynamically significant shunt(PDA), recurrence of symptomatic PDA, complications of Indomethacin, or contraindi cations to Indomethacin.

• Journal of Chest Surgery
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• v.29 no.7
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• pp.747-752
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• 1996

Video-assisted thoracic surgery(VATS) has been widely used in the treatment of spontaneous pneumothorax in spite of the absence of definitive data regarding the relative safety and long term results of this procedure. We reviewed 34 patients (group I) who underwent )8 video-assisted surgical procedures for spontaneous pneumothorax from June 1994 to December 1995 and compared the results of these patients with the results of another 14 patients (group ll) who underwent bullectomy through axillary Oho- racotomy during the same period. Average age, sex distribution, site and extent of pneumothorax, surgical indications, and complication rate showed no differences between the two groups. In group ll patients, th number and sites of bullae tend to be multiple compared to patients in group 1. The mean number of ends-GIA used for stapling of bullae was 2. 6 per patient with the range from 2 to 4 in group 1. The mean duration of chest tube drainage was not different between the two groups ().7 days and 3.9 days), but the mean time to discharge was significantly shorter in group I (5.6 days) than in group ll (8.9 days). Mean follow-up time was 12 and 11 months in each groups and ranged from 2 to 21 months. Pneumothorax recurred after three of 38 procedures in group I (7.9 %) with no recurrence in group ll. These data suggest that video-assisted thoracic surgery is a viable alternative to thoracotomy for the treatment of spontaneous pneumothorax with low morbidity and shorter hospital stay. However, it should be applied cautiously to patients with spontaneous pneumothorax because of the relatively high incidence of recurrence compared to axillary thoracotomy.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.428-432
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• 2010

A 67 years old male patient was admitted with back pain that had recurred from 6 months previously. Eleven years previously, he underwent stent grafting at the descending thoracic aorta for a chronic Stanford type B aortic dissection. The preoperative computed tomography showed aortic dissection from the origin of the left subclavian artery to the bifurcation of the abdominal aorta, and there was a type I endoleak at the proximal portion of the stent graft and aneurysmal dilatation of the descending aorta. A hybrid endovascular repair was successfully performed, and this involved debranching and rerouting the aortic arch vessels under extracorporeal cardiopulmonary bypass and then this was followed 13 days later by stenting in the ascending aorta, the aortic arch and the descending aorta. The postoperative computed tomography showed complete exclusion of the type I endoleak. After discharge, he has been followed up for 8 months without any problems.

• Journal of Chest Surgery
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• v.52 no.6
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• pp.392-399
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• 2019

Background: The surgical strategies for carotid endarterectomy (CEA) vary in terms of the anesthesia method, neurological monitoring, shunt usage, and closure technique, and no gold-standard procedure has been established yet. We aimed to analyze the feasibility and benefits of CEA under regional anesthesia (RA) and CEA under general anesthesia (GA). Methods: Between June 2012 and December 2017, 65 patients who had undergone CEA were enrolled, and their medical records were prospectively collected and retrospectively reviewed. A total of 35 patients underwent CEA under RA with cervical plexus block, whereas 30 patients underwent CEA under GA. In the RA group, a carotid shunt was selectively used for patients who exhibited negative results on the awake test. In contrast, such a shunt was used for all patients in the GA group. Results: There were no cases of postoperative stroke, cardiovascular events, or mortality. Nerve injuries were noted in 4 patients (3 in the RA group and 1 in the GA group), but they fully recovered prior to discharge. Operative time and clamp time were shorter in the RA group than in the GA group (119.29±27.71 min vs. 161.43±20.79 min, p<0.001; 30.57±6.80 min vs. 51.77±13.38 min, p<0.001, respectively). The hospital stay was shorter in the RA group than in the GA group (14.6±5.05 days vs. 18.97±8.92 days, p=0.022). None of the patients experienced a stroke or restenosis during the 27.23±20.3-month follow-up period. Conclusion: RA with a reliable awake test reduces shunt use and decreases the clamp and operative times of CEA, eventually resulting in a reduced length of hospital stay.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1B
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• pp.47-55
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• 2011

This study suggests new synthetic unit hydrograph method considering hydrodynamic characteristic on the basin. The suggested method based on width function GIUH, and the procedure is summarized as follows; 1) Draw up a travel distance distribution map (width function) which is raster of length between from center of individual cells to the outlet by GIS. 2) Calculation of travel time distribution map (rescaled width function) by hydrodynamic parameters and travel distance distribution map. 3) Derivation of IUH and Duration UH from rescaled width function. 4) Comparison of shape of UH between suggested method and existing synthetic unit hydrograph methods. The target basins are selected Ipyeong and Tanbu subwatershed in the Bocheong Basin. The target basins are similar scale (watershed area), but different drainage structure (drainage density et al.). Therefore we anticipate that there are different hydrologic response functions because different hydrodynamic characteristics. As a result of derivation of UH, existing synthetic unit hydrograph methods are similar shape of UHs about Ipyeong and Tanbu watersheds, but the suggested method is different shape of ones. As a result of application to observed data, the peak discharge by suggested method is similar to existing synthetic unit hydrograph methods, but the peak time is well correspondence between those. Henceforth, if the suggested method combines with the rational velocity estimation method, it is useful method for synthetic of UH in ungauged watershed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.937-945
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• 2013

The accuracy of flood inundation maps is determined by the uncertainty propagated from all variables involved in the overall process including input data, model parameters and modeling approaches. This study investigated the uncertainty arising from key variables (flow condition and Manning's n) among model variables in flood inundation mapping for the Missouri River near Boonville, Missouri, USA. Methodology of this study involves the generalized likelihood uncertainty estimation (GLUE) to quantify the uncertainty bounds of flood inundation area. Uncertainty bounds in the GLUE procedure are evaluated by selecting two likelihood functions, which is two statistic (inverse of sum of squared error (1/SAE) and inverse of sum of absolute error (1/SSE)) based on an observed water surface elevation and simulated water surface elevations. The results from GLUE show that likelihood measure based on 1/SSE is more sensitive on observation than likelihood measure based on 1/SAE, and that the uncertainty propagated from two variables produces an uncertainty bound of about 2% in the inundation area compared to observed inundation. Based on the results obtained form this study, it is expected that this study will be useful to identify the characteristic of flood.

• The Korean Nurse
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• v.36 no.2
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• pp.73-83
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• 1997

Bed rest is recommended to prevent postlumbar puncture headaches(PLPHA), but the period of bed rest varies in the literature from 6 hours to 24 hours. In clinical practice the period of bed rest varies but nursing methods for adults and children have little difference. In Seoul National University Hospital, children have been given at least 6 hours bed rest after a lumbar puncture. Pediatric oncology patients require a lumbar puncture for an initial diagnosis, follow up treatment or administration of chemotherapeutic agent. But it is difficult for young children to lie supine or to refrain from their usual activities in any way, and unpleasant problems related to a shortage of beds often occurs during discharge or in an outpatient setting. The purpose of this study is to substantiate the preventive effect of PLPHA by the period of bed rest, to identify the other factors that influence PLPHA, and to use the nursing methods proper to children. The subjects were 65 children, ages 1-17, undergoing treatment in the children's cancer center at SNUCH during the period June 1, 1995, to Aug. 31, 1995. The team nurses asked questions about PLPHA of the parents and children in order to fill out a questionnaire. The data were evaluated by percent, t-test, Chi-square test and Mann-Whitney U test. Result; 1. There was no significant difference relating the bed rest time spent to the occurrence of postspinal headaches (t-test). 2. There was a significant risk of PLPHA in the children who were irritable before procedure and/or had experienced previous PLPHA(p<0.05, ${x^2}-test$). 3. The following factors were not found to be associated with increased risk of PLPHA: previous puncture experience, giving analgesics, the choice of puncturist, inpatient/outpatient status, gauge of needle, purpose, the amount of CSF removed, gender, diagnosis, the number of peripheral WBCs, previous lumbago experience after LP, position after bed rest, age, the number of aural puncture at the time. A longer period of bed rest is unlikely to be more effective to prevent PLPHA and seems impractical. A shorter period will save time and effort. Perhaps it will also allay some of the fears which surround LP. So 1 hour bed rest after LP is suggested and nursing methods for emotional support should be investigated to reduce PLPH.

• Journal of Korea Water Resources Association
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• v.49 no.5
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• pp.451-458
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• 2016

In order to infer regional flood frequency for ungauged watersheds, index flood method was applied for this study. To pursuit this given purpose, annual peak flood data for 22 watersheds located at the upstream of the Chungju Dam watershed were obtained from the spatial extension technique. The regionalization of mean annual flood was performed from extended flood data at 22 points. Based on the theory that flood discharge and watershed size follows the power law the regionalization generated the empirical relationship. These analyses were executed for the full size of the Chungju Dam watershed as one group and three different mid-size watersheds groups. From the results, the relationship between mean annual flood and watershed sizes follow the power law. We demonstrated that it is appropriate to use the relationship between specific flood discharges from the upper and lower watersheds in terms of estimating the floods for the ungaged watersheds. Therefore, not only the procedure of regional frequency analysis but also regionalizaion analaysis using finer discretization of the regions interest with respect to the regional frequency analyisis for the ungauged watersheds is important.