• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.51-56
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• 2006

A computer code was developed to simulate both the thermal stresses introduced during the post-filling stage and the in-plane deformation after ejection process by finite element method based on the plane stress theory. The computer simulation was applied to the mold design of a 2 inch light guide plate (LGP) for thin film transistor (TFT)-liquid crystal displays (LCD). With injection molding experiments based on the design of experiments (DOE) technique, the influences of the processing conditions in injection molding on brightness and uniformity of the LGP were investigated, and the optimal processing parameters were selected to increase the brightness and uniformity. The verification experiment showed that the brightness and uniformity of the LGP were increased dramatically under the selected optimal processing conditions.

• ETRI Journal
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• v.25 no.3
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• pp.156-170
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• 2003

Gamut compression algorithms have traditionally been defined functionally and then tested with deductive methods, e.g., psychophysical experiments. Our study offers an alternative, an inductive method, in which observers judge image colors to represent the original images more accurately. We developed a computer-controlled interactive tool that modifies the color appearance of pictorial images displayed on a monitor. In experiments, observers used the tool to alter color pixels according to the region of color space to which they belonged. We created three different gamut compression algorithms based on the observer experimental data. Observer groups evaluated the performance of the newly-developed algorithms, existing gamut compression algorithms, and an image based on the average observers' results from experiments in this study. The study of gamut extension is unlike the study of gamut compression in that it mainly deals with the degree of image pleasantness as judged by observers. The results of the gamut extension experiments in this study not only make available worthwhile data but also suggest a methodology for using the observer experimental tool for future gamut extension research.

• 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.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.73-77
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• 2002

Applying the computer interface cards installed to old-fashioned, used PENTIUM I for the basic optical experiment makes students to have more attention and interests in the experiment, and enhanced the accuracy of the optical experiment. When applied for the light diffraction experiment, the above way of results made the experiment more accurate comparing with those of other experiments operated in advance. In addition, they turned out to be as same as the data in theory. Applying the above way not only for the basic optical experiments to recycle old-fashioned PCs being abandoned but also for the automation of optical experiments in manual could enhance the efficiency of the experiment a lot.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1794-1797
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• 2003

We developed a web-based virtual laboratory system for electronic circuit experiments on the client/ server distributed environment. Through our virtual laboratory, the learners will be capable of learning the concepts and theories related to electronic circuit experiments and how to operate the experimental equipments such as multimeters, function generators, digital oscilloscopes and DC power suppliers. The proposed virtual laboratory system is composed of four important components: Principle Classroom to explain the concepts and theories of electronic circuit operations, Virtual Experiment Classroom to provide interactive multimedia contents about the syllabus of off-line laboratory class, Assessment Classroom, and Management System. With the aid of the Management System every classroom is organically tied together collaborating to achieve maximum learning efficiency. We have obtained several affirmative effects such as high learning standard, reducing the total experimental hours and the damage rate for experimental equipments.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.129-136
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• 2017

This paper aims to establish a guideline for ridership capacity of different rail vehicles for military passengers. Previous guideline is limited only to a Mungungwha(hauled by diesel locomotive) vehicle, but this paper expands the limitation to ITX- Saemaeul and urban rail vehicles classified to Electric Motivated Unit(EMU). The guideline considers both with and without personal armor conditions, and based on repetitive ridership experiments. The experiments are designed under considerations of the required number of soldiers for the sample spaces of the different rail vehicles. Moreover, the design tries to establish a concept of optimal capacity additionally to a traditional limiting ridership capacity. In order to do this, ridership comfort is questioned to participant soldiers repetitively over the experiments and all answers of them are surveyed as a results of it. The results of the experiments presented by this paper can be referenced to establish a new guideline on ridership capacity for Korean army.

• Journal of The Korean Association For Science Education
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• v.21 no.3
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• pp.547-557
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• 2001

In this study, we compared the contents of cloud making experiments in middle school science textbooks of 5th and 6th science curriculum from the viewpoint of methods and apparatus. And we analyzed the problems of the experimental methods and apparatus based on the thermodynamic theories. A new experiment was developed to solve the problems, and the effects of new experiment were compared with those of the experiments in the textbooks.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.408-413
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• 2001

The structural optimization is carried out in the continuous design space or discrete design space. Methods for discrete variables such as genetic algorithms are extremely expensive in computational cost. In this research, an iterative optimization algorithm using orthogonal arrays is developed for design in discrete space. An orthogonal array is selected on a discrete design space and levels are selected from candidate values. Matrix experiments with the orthogonal array are conducted. New results of matrix experiments are obtained with penalty functions for constraints. A new design is determined from analysis of means(ANOM). An orthogonal array is defined around the new values and matrix experiments are conducted. The final optimum design is found from iterative process. The suggested algorithm has been applied to various problems such as truss and frame type structures. The results are compared with those from a genetic algorithm and discussed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.3
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• pp.109-114
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• 2016

This study presents the optimal hardness range for a coated layer of a workpiece when the diamond tool cuts the corner-cube pattern on the coated plates using an ultra-precision diamond-turning machine. Two kinds of coated plates, which have the hardness range of 211~328 Vickers hardness, are used on the first experiments. The form accuracy for the corner-cube pattern could be achieved through the following experiments using the accumulated thin copper plates in second experiments, having optimal 265~275 Vickers hardness based on the basic first experiments without tool wear. When the number of machining adjustments was increased to seven times, having machining depth was reduced successively in second experiment, a fine surface could be achieved without tool wear.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.644-647
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• 2005

In this paper, computer simulations with the absolute nodal coordinate formulation for large deformation problems in flexible multibody dynamics are compared to the real experiments. A high speed camera was employed to capture the deformed shapes of a thin beam, a plate, a rotating chain, and a paper strip. The measured data was used to calculate precise values for stiffness and damping ratio of the objects. Also a rotating strip and a helicoseir problem were formulated for computer simulation, and the computational results are also compared to the experiments.