• Journal of Wetlands Research
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• v.13 no.2
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• pp.307-317
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• 2011

Recently, we have a growing interest in the washland construction for the function of flood control. Therefore this study analyzed flood reduction effect of washland using hydraulic experiment. We used open-channel unit for flood reduction effect of washland. And we used side weir to lateral structure. The result of hydraulic experiment showed a decrease of the average velocity and discharge according to the installation location of side weir. Also, we compared the results of HEC-RAS model and hydraulic experiment for the review of the result of hydraulic experiment. As the result, hydraulic experiment and HEC-RAS model have showed the similar results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.104-108
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• 2003

Finite element (FE) model updating is a procedure to minimize the differences between analytical and experimental results, which can be usually posed as an optimization problem. This paper aims to introduce a hybrid optimization algorithm (GA-SA), which consists of a Genetic algorithm (GA) stage and an Adaptive Simulated Annealing (ASA) stage, to FE model updating for a shrunk shaft. A good agreement of the first four natural frequencies has been achieved obtained from GASA based updated model (FEgasa) and experiment. In order to prove the validity of GA-SA, comparisons of natural frequencies obtained from the initial FE model (FEinit), GA based updated model (FEga) and ASA based updated model (FEasa) are carried out. Simultaneously, the FRF comparisons obtained from different FE models and experiment are also shown. It is concluded that the GA, ASA, GA-SA are powerful optimization techniques which can be successfully applied to FE model updating, the natural frequencies and FRF obtained from all the updated models show much better agreement with experiment than that obtained from FEinit model. However, FEgasa is proved to be the most reasonable FE model, and also FEasa model is better than FEga model.

• Journal of Korean Home Economics Education Association
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• v.10 no.1
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• pp.153-169
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• 1998

The purposes or this study were to develop the scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scales for the Home Economics Textiles class in high school. First, through review of literature concerned, scientific experimental model was defined, and the usefulness of this model on the teaching situation testified on other subjects such as Physics and Bilolgy, was reviewed. Secondly, scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scale were developer on the bases on APU evaluation model, experimental guidelines for teachers, experiment planning & report form for students, evaluation scale applicable to the teaching situation ere established by analysing the significant differences scientifically.

• Journal of Ocean Engineering and Technology
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• v.32 no.3
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• pp.202-207
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• 2018

This paper presents the efficiency of a floating vertical axis wind turbine with variable-pitch. A model was designed to use the lift force and drag force for blades with various pitch angles. The blade's pitch angle is controlled by the stopper. To validate the efficiency of the wind turbine discussed in this paper, a model test was carried out through a single model efficiency experiment and wave tank experiment. The parameters of the single model efficiency experiment were the wind speed, electronic load, and pitch angle. The wave tank experiment was performed using the most efficient pitch angle from the results of the single model efficiency experiment. According to the results of the wave tank experiment, the surge and pitch motion of a structure slightly affect the efficiency of a wind turbine, but the heave motion has a large effect because the heights of the wind turbine and wind generator are almost the same.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.424-435
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• 1991

To develop the photoelastic experiment method for the orthotropic material under pure torsional moment is the main objective of this research. In the development of photoelastic experiment for orthotropic material under pure torsional moment, the important problems and their solutions are the same as following. In the model material for photoelastic experiment, it was found that C.F.E.C.(Copper Fiber Epoxy Composite) can be used as the model material of photoelastic experiment for orthotropic material. In the stress freezing cycle, it was assured that stress freezing cycle for epoxy can be used as the stress freezing cycle of the photoelastic experiment for orthotropic material. In the slicing method, it was found that the negative oblique slicing method can be effectively used as slicing method in 3-dimensional photoelastic experiment. In the measuring method of stress fringe values and physical properties in the high temperature, it was found that stress fringe values can be directly measured by experiment and physical properties can be directly or indirectly by equation between stress fringe values and physical properties developed by author. In the stress analysis method of orthotropic material under pure torsional moment by photoelastic experiment, it will be studied in the second paper.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.158-158
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• 1999

• Journal of the Ergonomics Society of Korea
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• v.19 no.1
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• pp.37-48
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• 2000

Universal design is an approach to create environments and products that recognizes the diversity of users, regardless of their ability or age. Recently, old person and disabled person rapidly go on increasing in number. So, universal design concept becomes more and more important in product and environment, etc. In this study, we dealt with the universal design problem of microwave oven considering old persons. New design model for microwave oven was developed and evaluated using human factors approach. The principles of universal design was developed through literature survey and questionnaire survey for old persons, and then design alternatives were developed according to these principles. Two experiments were performed in this study. The purpose of the first experiment was to select final design alternative and the experiment was performed using rapid prototypes. The second one was a usability testing for the real model of final alternative. In this experiment, the real model was compared with the existing real product. As the result, the new design model was a little more excellent than the existing model in usability.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1209-1213
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• 2005

It reflects well feature of slope that is characteristic of city river basin of Pusan local. Process various hydrological datas and basin details datas which is collected through basin basis data. weather satellite equipment(EMS-DEU) and automatic water level equipment(AWS-DEU) and use as basin input data of ILLUDAS model, SWMM model and HEC-HMS model In order to examine outflow feature of experiment basin and then use in reservoir design of experiment basin through calibration and verification about HEC-HMS model. Inserted design rainfall for 30 years that is design criteria of creek into HEC-HMS model and then calculated design floods according to change aspect of the impermeable rate. Capacity of reservoir was determined on the outflow mass curve. Designed imagination reservoir(volume $54,000m^3$) at last outlet upper stream of experiment basin, after designing reservoir. It could be confirmed that the peak flow was reduced resulting from examining outflow aspect. Designing reservoir must decrease outflow of urban areas.

• Journal of Environmental Science International
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• v.11 no.12
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• pp.1321-1326
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• 2002

A numerical model is investigated to predict a behavior of the gaseous volatile organic compounds and a subsurface contamination caused by them in the unsaturated zone. Two dimensional advective-dispersion equation caused by a density difference and two dimensional diffusion equation are computed by a finite difference method in the numerical model. A laboratory experiment is also carried out to compare the results of the numerical model. The dimensions of the experimental plume are 1.2m in length, 0.5m in height, and 0.05m in thickness. In comparing the result of 2 methods used in the numerical model with the one of the experiment respectively, the one of the advective-dispersion equation shows better than the one the diffusion equation.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.5
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• pp.1190-1201
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• 1995

Photoelastic experiment has been restricted by three significant problems such as the problems of modeling for a complicated body, of development of experimental model material, and of residual stress in photoelastic specimen. The residual stress in photoelastic model materials is caused by molding, cutting and time effects, etc.. Especially, large residual stress exists on the interface of photoelastic model material for bi-material. Small residual stress occurred in the photoelastic model materials is usually neglected in the photoelastic experiments. But the residual stress provides some errors in the results of photoelastic experiments. In this paper, the stress optic law which can be effectively applied to the phtoelastic model materials with residual stress is developed. By using this stress optic law, we can obtain good results from isochromatic fringe patterns of photoelastic experiment specimen in which residual stress are involved. The stress optic law can be applied to obtain good results of photoelastic experiment from composite materials or bimaterials.