• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.847-852
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• 2000

This paper presents an evaluation of the behavior and strength of two pre-tensioned concrete deep beams tested to failure with using the nonlinear strut-tie model approach. In the approach, the effective prestressing forces represented be equivalent external loads are gradually introduced along its transfer length in the nearest strut-tie model joints, the friction at the interface of main diagonal shear cracks is modeled by diagonal struts along the direction of the cracks in strut tie-model, and additional positioning of concrete ties a the place of steel ties is incorporated. Through the analysis of pre-tensioned concrete deep beams, the nonlinear strut-tie model approach proved to present effective solutions for prediction the essential aspects of the behavior and strength of pre-tensioned concrete deep beams.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.255-263
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• 2009

The antifungal activity of silver, copper, and titania nanoparticles against fungal spores was investigated. Cladosporium cladosporioides spores were aerosolized and sampled on a solid agar plate using an Anderson impactor. The solid agar plate contained different concentration of nanoparticles ranging from 0 to $500{\mu}g/mL$. Silver and copper nanoparticles were shown to be an effective antifungal agent, while titania nanoparticles were not. Antifungal activity of these effective nanoparticles appeared at $300{\mu}g/mL$ concentration.

• Transactions of Materials Processing
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• v.15 no.3 s.84
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• pp.226-231
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• 2006

The fuel injector is a pa.1 that controls the fuel supply of automotive engine. The housing of the fuel injector supports the rod, the needle valve and the solenoid. In this study, the rigid-plastic FE-analysis by using the design of experiments (DOE) and the response surface methodology (RSM) has been performed to produce the product reducing the under-fill and the maximum effective strain. From the results of DOE, the stem of counter punch and the face angle of punch at the $1^{st}$ process, and the stem of punch at the $2^{nd}$ process were determined as the significant design variables far each response such as the upper under-fill, lower under-fill and the maximum effective strain. From the results of RSM, the optimal values of the design variables have been also determined by simultaneously considering the responses.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.1
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• pp.61-69
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• 2001

This study concerns designing effective fuzzy inference rules, which can be used to evaluate other experiment sets for sensory tests. The number of fuzzy inference rules might be determined by the fuzzy division of variables. For the more the number of fuzzy division does not mean the more effectiveness, the number of inference rules should be reduced to improve efficiency of inference engine of expert system. This study verified that its suggested method and inference rules are effective in comparison with the existing studies.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.188-194
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• 2009

Consolidation settlement, a crucial parameter in geotechnical design of soft ground, has not been computed in a unique way due to different computation methods in practice. To improve computational error in calculating consolidation settlement, a number of researches has been attempted. Conventional 1-dimensional consolidation theory assumes the center of the clay layer as the representative point to obtain effective stress in calculation, which could resort to erroneous results. To calculate exact solutions considering initial distribution of effective stress, diving a stratum into multi-layers could resort to wasting time and effort. In the study, a novel methodology for calculating consolidation settlement via Guassian quadrature is developed. The method generally is capable of computing settlements in any case of the stress conditions encountered in fields.

• Journal of The Korean Association For Science Education
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• v.22 no.5
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• pp.1071-1081
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• 2002

This article describes the status of science teacher education in Taiwan. The pre-service and in-service science teacher training system, institutes, curricula, programs, and evaluation on the institutes were briefly introduced. The differences before and after the 1996 reform of science teacher training system were compared. Finally, the attempts and efforts that have been done through the channels of research to promote science teachers' professional development were addressed. These efforts include the Case studies of exemplary science teachers' teaching performances, the development of licensure instruments for the certification of science teachers, the use of computers and distance education for supervising student teachers, the exploration of promoting science teachers' understanding about the nature of science, the exploration of promoting science teachers' pedagogical content knowledge, the exploration of promoting science teachers' ability of increasing effective student-teacher and student-student interactions, and the exploration of effective teaching strategies.

• Smart Structures and Systems
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• v.5 no.4
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• pp.469-482
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• 2009

The emerging sensor-based structural health monitoring (SHM) technology has a potential for cost-effective maintenance of aging civil infrastructure systems. The author proposes to integrate continuous and global monitoring using on-structure sensors with targeted local non-destructive evaluation (NDE). Significant technical challenges arise, however, from the lack of cost-effective sensors for monitoring spatially large structures, as well as reliable methods for interpreting sensor data into structural health conditions. This paper reviews recent efforts and advances made in addressing these challenges, with example sensor hardware and health monitoring software developed in the author's research center. The hardware includes a novel fiber optic accelerometer, a vision-based displacement sensor, a distributed strain sensor, and a microwave imaging NDE device. The health monitoring software includes a number of system identification methods such as the neural networks, extended Kalman filter, and nonlinear damping identificaiton based on structural dynamic response measurement. These methods have been experimentally validated through seismic shaking table tests of a realistic bridge model and tested in a number of instrumented bridges and buildings.

• Korean Institute of Interior Design Journal
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• v.16 no.3 s.62
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• pp.111-118
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• 2007

Using effective light, which is physical experiences by its control and manner of adaption, and make human to recognize the shape and give the meaning, so that approaching against perception experimental method which plays a role in basic clue, is regarded crucial highly among human sensory organ. this study consider the perception conception, its feature and necessity against eyes' adaption among human perception experimental experiences which has been discussed indifferently for inner space. Also, we looked over the problems among actual examples of inner spaces which should be considered as to adaption conception of human beings. Furthermore, this study aims at basic studying, which searching for enable to adapt in case of planning for inner space planning and distributing the quality evaluation by using effective light.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.04a
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• pp.202-211
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• 1996

A number of typical type of steel-box pedestrian bridges are constructed in the metropolitan highway or heavy traffic urban area. Although it has the advantage of speedy construction because of its simple structural form and prefabricated erection method, it has been reported that many of these bridges are deteriorated or damaged and thus are in the state such that it would give unsafe and uncomfortable feeling to pedestrians. In the paper, for the realistic assessment of safety and residual earring-capacity of deteriorated and/or damaged steel box pedestrian bridges, an interactive non-linear limit state model are formulated based on the von Mises' combined stress yield criterion. It is demonstrated that the proposal model is effective for the reliability-based safety assessment and residual carrying-capacity evaluation of steel-box pedestrian bridges. In addition, this study suggests an effective and practical field load test method for pedestrian bridges.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.45
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• pp.155-163
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• 1998

Recently, as the quality is being recognized as elementary and strategic means to improve the international competetiveness of a business, there may be few business who do not operate quality control meeting or system for their production lines. In other words, local businesses operate some types of quality control system half voluntarily and half compulsorily without having verifying their efficiency. Under such a circumstance, this study is aimed at determining the factors which local businesses are required to assess for their quality system. It is believed that the results of this study can be used as a tool for local businesses to assess their quality system. The effective identification of problems regarding the quality system depends on how precisely the activities of quality system can be performed. Upon correct identification of problems, desirable directions can be explored. All in all, the model developed through this study may be useful as quality system assessment tool.