• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.138-144
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• 2013

The automation technology for overlay welding is needed due to the occurrence of severe corrosion and abrasion on the surface of internal contact in different shape of fittings. In Korea, different shapes of fittings have been manufactured by using the imported equipment of overlay welding automation at some companies. Thus the research on the development of overlay welding automation system (in short, OWAS) for a large L-type tube is urgently needed. In this paper, the investigation is focused on the optimal design of a supporting base for the (currently developing) OWAS of large L-type tube. Specifically we assume that the base which supports the equipment during the process of overlay welding is loaded as self-weight in the direction of gravity through static analysis especially when it is rotated 180 degree on the OWAS. For optimal design of a supporting base for OWAS of large L-type tube, Solidworks(R) (for 3-dimensional modelling) and ANASYS Workbench(R) (for structural analysis) are incorporated so as to proceed an optimization routines based on Response Surface Method (RSM) and Design of Experiment (DOE). In more specific, DOE finds out major factors (or dimensions) of the supporting base by using MINITAB(R). Then the regression equations between design variables (the major factors of supporting base) and response variables (deformation, stress and safety factor for the supporting base), which will be resulted in by RSM, verify the major factors of DOE. In the next step, Central Composite Design (CCD) plans 20 simulations of ANASYS Workbench(R) and then figures out the optimal values of design variables which will be reflected on the manufacturing of supporting base. Finally welding experiment is conducted to figure out the influence of overlay welding quality in applying the optimized design values of supporting base to the actual OWAS.

• Journal of Broadcast Engineering
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• v.25 no.2
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• pp.275-278
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• 2020

In this paper, we proposed a deep learning based character recognition system through virtual data generation. In order to secure the learning data that takes the largest weight in supervised learning, virtual data was created. Also, after creating virtual data, data generalization was performed to cope with various data by using augmentation parameter. Finally, the learning data composition generated data by assigning various values to augmentation parameter and font parameter. Test data for measuring the character recognition performance was constructed by cropping the text area from the actual image data. The test data was augmented considering the image distortion that may occur in real environment. Deep learning algorithm uses YOLO v3 which performs detection in real time. Inference result outputs the final detection result through post-processing.

• Korean Journal of Clinical Pharmacy
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• v.1 no.1
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• pp.31-36
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• 1991

Tobramycin is one of the most frequently selected agents for pharmacokinetic drug monitoring because of its narrow therapeutic index and essential role for the management of serious infections, especially gram-negative infections. Its pharmacokinetic parameters are dependent on race, sex, age, ideal body weight. disease states, and etc. Therefore, to schedule the dosing of tobramycin, the individual pharmacokinetic parameters such as half-life and volume of distribution are needed. However, these pharmacokinetic parameters have never been reported in Koreans. The purposes of this study were to evaluate the volume of distribution of tobramycin in cancer patients who had normal renal function, to compare the mean values of Vd reported in the literature, and to compare the measured half-life with the expected half-life based on ABW, LBW, and IBW, respectively. Venous blood samples were collected just before and thirty minutes after dosing during steady state. Serum tobramycin concentrations were determined by $TD_x$ (fluorescence immunoassay). IBW were measured by the method of Devine: and LBW were measured by the method of Hallynck. Creatinine clearances (CLcr) of the patients were estimated using the Cockcroft and Gault equation. Elimination rate constants (kel) were determined using the Welling and Craig equation. Infusion rate (ko), volume of distribution (Vd), and half-life $(t_{1/2})$ were determined using the Saw chuk and Zaske equation. The volume of distribution Was $27\%$ greater than the Schentag's study (0.26 vs 0.33 l/kg), but the half-life was similar to the Levy's study. The predicted half-lives based on IBW were the closest to actual half-lives (1.85 vs 2.01 hr).

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.245-255
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• 2001

Existing cut-and-cover tunnels are designed regardless of cut-slope under the assumption that the overburden weight of backfill soil acts on tunnel arch and the earth pressure at rest acts on tunnel walls. However, actual earth pressures acting on the tunnel lining depend on open-cut size composed of cut-slope and cut-width, and thus the tunnel lining shows a different structural behavior. This study investigated the effect of cut-slope on structural behavior of the cut-and-cover tunnel lining as follows; Firstly, a comprehensive numerical analysis method using FLAC2D code was used and verified by field measurements of tunnel profile. Secondly, based on the verified numerical analysis technique, earth pressure acting on the lining, and displacement and sectional force developed on the lining were estimated with various shapes of cut-slopes$30^{\circ}\;, 456{\circ},\; 60^{\circ},\; and\;75^{\circ}%). Numerical analysis results indicate that the steeper cut-slope shows the more displacement and moment of the tunnel lining.

• Journal of the Korea Safety Management & Science
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• v.9 no.3
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• pp.55-61
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• 2007

In general, it is fact that most educational institutions have lots of problems about shift of education facility and equipment because of insufficient budget. However, most high school girls live a lot of period in the school and most of them wear student uniform. Thus, it is necessary that educational environment has to be improved by actual body size of high school girls. The main objective of this study is to provide numerical guideline for the improvement of educational environment about high school girls ($17\sim19$ years) through comparison and analysis on physical standard of nation (report published in 1997). The sample for this work chosen from data which were collected and measured by Size Korea during two years $(2003\sim2004)$. In order to analyze feature of the somatotype of high school girls, analysis was performed about 734 subjects on 25 body parts such as height (7 parts), width (4 parts), thickness (4 parts), circumference (5 parts), length (4 parts) and body weight. For the specific comparison on somatotype, $R\ddot{o}hrer$ index and Mollison's comparison graph were used. The result of this study can be utilized in various fields such as design of classroom, student uniforms, facilities and equipments for education, etc.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.209-213
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• 2020

In this study, the model A with the existing shape used at racing car and the model B with light weight were designed. The structural analysis with thermal deformation and stress were carried out. Model A shows that the maximum temperature is lower than model B. The cooling performance due to the shape of the disk without any other cooling conditions can be shown to be better for model A. Model A was seen to be superior in durability as the thermal stress reduced by almost twice as much as model B. The part where the greatest stress occurred appeared to be the hole jointed with the hub regardless of its shape. The analysis results at this study are seen to be useful at designing the shape of the actual vehicle brake disc. The analysis results obtained in this study can be applied at grasping the strength of the brake disk for racing car practically. By utilizing the analysis result of the brake disk for racing car, this study is seen as the convergence study that the aesthetic design and analysis are applied.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.218-225
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• 2014

Landslides, one of earth's natural disasters, increase every year due to heavy rainfall, and cause damage to human life and assets. This study used the SHALSTAB to predict places at risk of landslides, in accordance with the intensity of rainfall. The parameter value of transmissivity was $19.58m^2/day$, the internal friction angle $36.3^{\circ}$, and the saturated unit weight $2.03t/m^3$. The slope stability status was classified into four categories, namely: unconditionally stable, stable, unstable and unconditionally unstable. In order to evaluate the applicability of the SHALSTAB, actual landslide areas were checked, with the unstable area under 263 mm rainfall. 85.1% of them were consistent. And so we can identify the distribution of places at risk of landslides, on the basis of the intensity of rainfall by means of SHALSTAB.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.7
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• pp.105-111
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• 2009

This study was carried out to evaluate structural stability of the suspended plastic pedal used in vehicles and to predict its fatigue life with the results obtained from finite element analysis. And also shape optimization was performed to reduce its weight. Structural analysis of the suspended plastic pedal was based on the evaluation tests such as static test, stiffness test, and fatigue test in the actual field, which were frequently carried out in the companies manufacturing plastic pedals. The evaluation for the plastic pedal was carried out by structural and fatigue analyses using a commercial FEA program and according to it, maximum stress and strain and fatigue life of the pedal satisfied all the requirements in the evaluation tests. The results of structural analysis of the suspended plastic pedal were used in the fatigue analysis. Fatigue test was performed to verify validity of the theoretical fatigue life of the plastic pedal. And the life by theoretical calculation was in good agreement with that by the experiment. Object function for optimizing shape of the plastic pedal is its volume, and total volume of the plastic pedal was reduced to about 11.7% through shape optimization.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.511-515
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• 2005

Autologous cartilage grafts have become an integral part of aesthetic and reconstructive plastic surgery. However, little objective information is available about the actual quantitative resorption of cartilage in human. This study sought to objectively quantify and compare the resorption of costal cartilage in human. To compare the resorption characteristics of rib cartilage autografts, we harvested rib cartilage grafts from 37 microtia patients. All autografts were implanted subcutaneously on chest and then removed after 6 to 17 months. Graft mass and volume were compared before and after implantion. Rib cartilage grafts with perichondrium averaged $10.8{\pm}7.4%$ resorption by volume, On the other hand rib cartilage grafts without perichondrium $25.5{\pm}6.8%$. There was no evidence of necrosis or inflammatory changes. The rib cartilage is the preferred source of autogenous cartilage for auricular reconstruction. Short-term resorption of rib cartilage without perichondrium appears to be higher than with perichondrium. The low resorption of cartilage with perichondrium may be due to in part to cartilage forming capacity of the perichondrium. It remains to be seen whether these differences in resorption persist in the long term.

• Science of Emotion and Sensibility
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• v.12 no.4
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• pp.511-518
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• 2009

With the help of the advancements in information and communication, information appliances are changing. Flat panels made it possible for information appliances to become smaller in size and lighter in weight, and high end graphics provide increase in realistic and immersive use. Even with these advancements interest in design for laboratory equipment tend to only stay on a level of the exterior of the equipment, not to the point of designing the interface of display GUI. Inspired with the problem above this research would contain the preference analysis ondisplay GUI design considering the characteristics of the main users and the laboratory equipment itself. The test would be held through comparison of graphic-based display GUI and text-based display GUI and analyzing the task time and number of errors made, looking for which display GUI scientist prefer. The test results show that text-based GUI has a higher efficiency but the actual users preferred the graphic-based display GUI.