• Archives of Plastic Surgery
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• v.34 no.6
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• pp.713-718
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• 2007

Purpose: The aim of this study is to develop and apply the critical pathway to the orbital wall fracture patients and to elucidate its effect. Methods: Critical pathway(CP) sheet and questionnaire were developed by a team approach. Critical pathway was applied to 7 orbital wall fracture patients (CP group) from April 2006 to September 2006. Length of hospitalization and cost for hospitalization of CP group were compared to those of the 10 patients who had same disease entities and treated by conventional regimen(control group). Results: Length of hospitalization in the CP group (7.20 day) were insignificantly shorter than that of control group(8.71 day). Mean cost for hospitalization of the CP group(776,398 won) were insignificantly lower than that of control group(1,028,531 won). The patients satisfaction for the explanation regarding operation procedure, therapeutic operation fee, length of hospitalization and medical personnel were all affirmative. Conclusion: Critical pathway that we developed for orbital wall fracture definitely improved the quality of treatment. Furthermore, other critical pathways should be developed for another facial trauma patients.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.213-217
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• 1997

The semi-active recoil system provides automatic hydraulic pressure and recoil length by an exteral impulse compared with the conventional recoil system. We developed the proto type of recoil system and validated the performance through simulation and experiment. The main issue of the system is how to adjust pressure and length simultaneously. The system consists of external pressure control valve and flow control valve outside of cylinder. The pressure control valve control the cylinder pressure and recoil length. The controlled system enhances the control performance.

• International Journal of Concrete Structures and Materials
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• v.4 no.1
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• pp.63-68
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• 2010

With the emergence of ultra-high strength of concrete, the compression lap splice has become an important area of interest. According to ACI 318-08, a compression splice can be longer than a tension splice when high-strength concrete is used. By reevaluating the test results of compression splices and performing regression analysis, a simplified design equation for splice length in compression was developed based on the basic form of design equations for development/splice lengths of deformed bars and hooks in tension. A simple linear relation between $l_s/d_b$ and $f_{sc}\sqrt{f'_c}$ was assumed, and yields good values for the correlation coefficient and the mean and the COV (coefficient of variation) of the ratios of tests to predictions of splice strengths in compression. By including the 5% fractile coefficient of 0.83, a design equation for splice length in compression was developed. The splice length calculated using the proposed equation has a reliability that is equivalent to other provisions for reinforcing bars.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.34-40
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• 2017

The catastrophic collapse of the in-boiler scaffolding system in the two thermal power plants occurred in March and April 2012. After site investigation and document review, it was found that the specialized scaffolding system was imported for overhaul & maintenance and that the system did not get the safety certification at the import. In this regard, this study developed & proposed an access platform and a support for the vertical tube section of the super heat as well as a variable-length platform for the horizontal tube section, satisfying the domestic certification standards. The access platform was developed to be easy to handle by the worker with a weight of about 0.069 kN, which could reduce the risk of falling accidents and workers' musculoskeletal diseases. For the variable-length platform, it is possible to cope with various changes in length between the horizontal tubes associated with the increase of rigidity in the overlapping and the elimination of the protrusion.

• Computers and Concrete
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• v.15 no.2
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• pp.141-166
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• 2015

In the present study, a Finite Element Model has been developed and used to study the effect of diameter to wall thickness ratio (D/t) of steel tube filled with concrete under axial loading on its behavior and load carrying capacity. The model is verified by comparing its findings with available experimental results. Influence of thickness and area of steel tube on strength, ductility, confinement and failure mode shapes has been studied. Strength enhancement factors, load factor, confinement contribution, percentage of steel and ductility index are defined and introduced for the assessment. A parametric study by varying length and thickness of tube has been carried out. Diameter of tube kept constant and equals to 140 mm while thickness has been varied between 1 mm and 6 mm. Equations were developed to find out the ultimate load and confined concrete strength of concrete. Variation of lateral confining pressure along the length of concrete cylinder was obtained and found that it varies along the length. The increase in length of tubes has a minimal effect on strength of tube but it affects the failure mode shapes. The findings indicate that optimum use of materials can be achieved by deciding the thickness of steel tube. A better ductility index can be obtained with the use of higher thickness of tube.

• Structural Engineering and Mechanics
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• v.74 no.3
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• pp.313-323
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• 2020

Non-destructive tests are commonly used in construction industry to access the quality and strength of concrete. However, till date there is no non-destructive testing method that can be adopted to evaluate the bond condition of reinforced concrete beams. In this regard, the presented research work details the use of ultra-sonic pulse velocity test method to evaluate the bond condition of reinforced concrete beam. A detailed experimental research was conducted by testing four identical reinforced concrete beam samples. The samples were loaded in equal increments till failure and ultra-sonic pulse velocity readings were recorded along the length of the beam element. It was observed from experimentation that as the cracks developed in the sample, the ultra-sonic wave velocity reduced for the same path length. This reduction in wave velocity was used to identify the initiation, development and propagation of internal micro-cracks along the length of reinforcement. Using the developed experimental methodology, researchers were able to identify weak spots in bond along the length of the specimen. The proposed method can be adopted by engineers to access the quality of bond for steel reinforcement in beam members. This allows engineers to carryout localized repairs thereby resulting in reduction of time, cost and labor needed for strengthening. Furthermore, the methodology to apply the proposed technique in real-world along with various challenges associated with its application have also been highlighted.

• Structural Engineering and Mechanics
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• v.80 no.5
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• pp.585-594
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• 2021

Ductility is very important parameter in seismic design of RC members such as beams where it allows RC beams to dissipate the seismic energy. In this field, the curvature ductility has taken a large part of interest compared to the deflection ductility. For this reason, the present paper aims to propose a general formula for predicting the deflection ductility factor of RC beams under mid-span load. Firstly, the moment area theorem is used to develop a model in order to calculate the yield and the ultimate deflections; then this model is validated by using some results extracted from previous researches. Secondly, a general formula of deflection ductility factor is written based on the developed deflection expressions. The new formula is depended on curvature ductility factor, beam length, and plastic hinge length. To facilitate the use of this formula, a parametric study on the curvature ductility factor is conducted in order to write it in simple manner without the need for curvature calculations. Therefore, the deflection ductility factor can be directly calculated based on beam length, plastic hinge length, concrete strength, reinforcement ratios, and yield strength of steel reinforcement. Finally, the new formula of deflection ductility factor is compared with the model previously developed based on the moment area theorem. The results show the good performance of the new formula.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.6
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• pp.1060-1071
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• 1997

The purpose of this study is to identify the effect of clothing cues(sleeve and skirt width, length) on female impressions. The experimental materials developed for this study are a set of stimuli and response scales. The stimuli are 16 pictures manipulated with sleeve and skirt width · length variations by computer drawing. The experimental design consists of 3 factorial design: (1) sleeve shapes(plain, upper expanded, below expanded, all expanded) (2) skirt width (wide, narrow) (3) skirt length(long, short) The 7-point semantic differential response scale designed for visual evaluation of female' s impression formation on sleeve shape and skirt width · length is 27 bipolar adjectives. The results of this study are as follows: 1. When we analize the impressions of female figure by sleeve shape and width · length of skirt, it becomes clear that maturity, modernity, attention, elegance and tenderness are proved to be important. Among these five factors, maturity, modernity and attention are identified as more important ones. 2. Sleeve shape have an effect on all factors except maturity and the effects of sleeve on the four factors are not striking. ' Width of skirt are most influential to the maturity and attention, but it does not have any effect on modernity. However two factor, that is width of skirt and sleeve have an effects on modernity, attention and tenderness. ' The length of skirt has an effects on the tenderness, elegance and modernity, but it dose not have any effect on attention. But width and length of skirt have an effects on attention, tenderness and modernity The length of skirt and sleeve have an effect on tenderness.

• Structural Engineering and Mechanics
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• v.5 no.5
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• pp.553-563
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• 1997

A procedure is being developed for bolting plates to the sides of existing reinforced concrete beams to strengthen and stiffen them. Unlike standard composite steel and concrete beams in which there is longitudinal-partial-interaction at the steel/concrete interface (that is slip along the length of the beam), composite bolted side-plated reinforced-concrete beams are unique in that they also exhibit transverse-partial-interaction, that is slip transverse to the length of the beam. In this work, the fundamental mathematical models for transverse-partial-interaction and its interaction with longitudinal-partial-interaction are developed. The fundamental models are then further developed to determine the number of connectors required to resist the transverse forces and to limit the degree of transverse-partial-interaction in bolted side-plated reinforced concrete beams.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.540-545
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• 1997

An analytical and experimental investigation has been performed on the heated length-to-diameter effect on critical heat flux for fixed exit conditions. A L/D correction factor is developed by applying artificial neural network and conventional regression techniques to the KAIST CHF data base. In addition, experiment is being performed to validate the developed L/D correction factor with independent data. Assessment shows that the developed correction factor is promising for practical applications.