• Journal of Fisheries and Marine Sciences Education
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• v.20 no.3
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• pp.473-486
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• 2008

This study was to compare 'experiment' presentation types of middle school science textbooks of Korea, Japan, and China and to draw some implication for the improvement of Korean science textbooks. It analyzed the experiments from the unit 'Light' of science textbooks which is common content in all three different science textbooks. The researchers analyzed the experiments with two questions. First, how is the experiment organized? Second, what role does each element of the experiment is playing in the experiment setting? The findings of international comparative analysis of experiment presentation types of middle school science textbooks of three countries were as follows. First, the Korean and Chinese textbooks tended to present the experiments without enough information for the experimental process and method, whereas the Japanese textbook tended to present the experiment with detailed information for the experimental method and process. Second, whereas the Korean and Chinese textbooks tended to have a loosened relationship among pre-experimental content, experiment, after-experiment content, the Japanese textbook tended to have an organic relationship among pre-experimental content, experiment, after-experiment content.

• Journal of Ocean Engineering and Technology
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• v.34 no.4
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• pp.253-262
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• 2020

This study provides a comparative analysis of experiments-based enhancements and sensitivity evaluations for the structural design of an automatic ocean salt collector under various load conditions. The sizing variables of the structural members were considered as design factors. The strength and weight performances were selected as output responses. The design of experiments used in the comparative study consisted of the orthogonal array design, Box-Behnken design, and central composite design. The response surface model, one of the metamodels, was applied to the approximate model generation. The design enhancement performance metrics, including numerical costs and weight minimization, according to the design of experiments, were compared from the best design case results. The central composite design method showed the most enhanced design results for the structural design of the automatic ocean salt collector.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.263-267
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• 2004

This paper presents a comparative study on numerical and wave-maker generated waves. The wave-makers employed to carry out the experiments have mathematical forms. The linear and quadratic models were tested. When it comes numerical analysis, the authors used the FLUENT which is widely used commercial code. Only two dimensional cases were considered. The experiments were done in a small wave flume. The waves were generated for various frequencies to examine the characteristics of the water waves. The comparison of the numerical and wave-maker generated waves were made.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.3
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• pp.194-201
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• 2003

This study presents the comparative filtration performance evaluation of automotive fuel filters based on the theory of Beta ratio. For the experiments, the fuel component's test stand incorporating the multi-pass filtration test circuit was developed. A mathematical description of filtration process in general was derived. And the theoretical basis of multi-pass test and the test procedure were described in detail. Experimental results revealed that domestic fuel filter tested could not maintain consistent Beta ratio, that is filtration efficiency, although it had the holding capacity of contaminants close to the specification at maximum pressure drop across the filter assembly. The results of experiments and simulations also showed that filtration system model could be refined including desorption ratio to estimate the variable Beta ratio in service life.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.1
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• pp.211-215
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• 2023

In this paper, the stability and effectiveness of the force control with a 6-axis compliance device are verified by performing comparative experiments with a commercial F/T sensor. The position/force control algorithm based on the Cartesian stiffness of a compliance device is briefly introduced and the design result of a 6-axis compliance device with F/T sensing is presented. The comparative experiments show that the force control using a compliance device is much more stable than that with rigid F/T sensor due to the enough compliance of a compliance device larger than robot positional resolution.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.283-284
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• 2014

In this paper, a comparative analysis of LCL and LLCL filters connected to three-level T-type PWM converters is presented, in which the filter inductor sizes are investigated in view of total harmonic distortion (THD) in grid phase currents. The analysis results are verified by simulation and experiments.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.267-270
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• 2001

It is difficult to install a ventilation window on the roof of single span greenhouse of arch shape. Investigation on the roof ventilation structure for those greenhouses was conducted. The effect of roof ventilation was evaluated by comparative experiments between greenhouse installing roof vent and having controlled side vent only. And ventilation efficiency was analyzed by experiments on the opening and closing operation of the roof and side vent.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.333-338
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• 1990

Most verification of improvements for adaptive control schemes are. dependent on computer simulations, but these computer simulations have much limitation, because (if complex actual conditions of system. This paper is concerned with the constructions of a thermal process system for experiments with various control schemes. This thermal process system is composed of a water tank, PC-XT, AD/DA converters power supply and thermal sensors. We estimate. the algorithms of pole-assignment adaptive control in the manifold disturbances and environments, changing system dynamics. The system equations for thermal press are included.

• Journal of the Korean Statistical Society
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• v.14 no.1
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• pp.48-55
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• 1985

In clinical trials subjects are avalible sequentially and must be assigned to treatments immediately. Completely randomized procedure for the allocation of treatments to each subject may result in severe imbalance among the number of subjects in treatment groups, especially for small experiments or interim analyses of large experiments. In this study, restricted randomization methods such as biased coin designs (Efron, 1971), permuted block design, and truncated binomial design are compared to teh completely randomized design in the presence of selection and/or accidential bias by Monte Carlo simulations.

• Computers and Concrete
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• v.17 no.3
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• pp.305-322
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• 2016

The work is intended to demonstrate that the loss of bond between concrete and flexural steel which led in recent years a number of flat-slab structures to punching collapse under service loading conditions is also relevant to ultimate limit-state design. It is based on a comparative study of the results obtained from numerical experiments on flat slab-column sub-assemblages. The slabs were designed for punching either in compliance with the EC2 code requirements, which do not allow for such loss of bond, or in accordance with the compressive force-path method which considers the loss of bond between concrete and the flexural reinforcement in tension as the primary cause of punching. The numerical experiments are carried out through the use of a nonlinear finite element analysis package for which, although ample published evidence of its validity exists, additional proof of its suitability for the purposes of the present work is presented.