• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.604-607
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• 2000

All of rubber tubes for force pump are imported from aboard there for locallization of these tubes is make a great contribution of Korean industry In this study compare with existing product of japan and designed the new one that is for our actual circumstances. Experimental work was performed to two kinds of specimen and compression test is performed for them. As a result specimen type A has a better restoration than other and minimum thickness is must over 12mm.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.335-340
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• 1998

The apparently different physical problems of lateral vibration and elastic stability of a linear member are limiting cases of a single phenomenon, the more general expression being the mode of vibration with end thrust. For a single-span beam-column, it is generally known that the square of the frequency of lateral vibration is approximately linearly related to compressive axial force. In this paper the relationship between the frequency and axial force of multi-span compression members is investigated by means of the finite element method.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.264-267
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• 2004

It is well known that axial tension decreases the shear strength of RC beams without transverse reinforcement, and axial compression increases the shear resistance. What is perhaps not very well understood is how much the shear capacity is influenced by axial load. RC beams without shear reinforcement subjected to large axial compression and shear may fail in a very brittle manner at the instance of first diagonal cracking. As a result, a conservative approach should be used for such members. According to the ACI Code, the concrete contribution is calculated by effect of axial force and the vertical force in the stirrups calculated by $45^{\circ}$ truss model. This study was performed to examine the effect of axial force in reinforced concrete beams.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.11
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• pp.39-45
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• 1998

Gas springs have been widely used in motor vehicles as well as in most areas of industry. Instead of coil springs, these gas springs are easily opreated to open(extension process) or close (compression process) the doors because $N_2$ gas with high pressure and oil are charged in tube. Most of manufacturers are using the trial ＆ error method in order to decide its specification(reaction force, damping force), which tends to waste time and money. Therefore, gas springs have been improved by properly changing the control pressure of $N_2$ Gas with its mounting location and weight to maximize its effect and to minimize its space. Although it has been researched on damping structure to minimize impact which is applied to vehicle when its back door is fully opened, the characteristics of damping structure are not known clearly. There(ore, this paper will not only clearly define the effect of important factors(open ＆ close force)for gas springs through theoretical analysis but also provide optimum design specification through development of program to avoid traditional method of specification determination such as the trail It error method which is widely used in whole industries including automotive industry.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.04a
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• pp.181-188
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• 2001

Due to many advantage of advanced composite material, research on the composite compression member is initiated. In this paper structural characteristics of concrete filled glass fiber reinforced composite tubular member is studied. Through 4-point flexural test with various level of axial force, the performance of composite compression member was analyzed. Also numerical method to find P-M diagram of composite compression member was developed. It is demonstrated that result of numerical method agree well with experimental results.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.95-104
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• 2003

The material properties of rubber was determined by the experiments of uniaxial tension, uniaxial compression, planer tension, equi-biaxial tension and volumetric compression. In compression test, it is difficult to obtain the pure state of compression stress and strain due to friction force between the specimen and compression platen. In this study, the stress and strain data from the equi-biaxial tension test were converted to compression stress and strain and compared to a pure state of simple compression data when friction was zero. The compression test device with the tapered platen was proposed to overcome the effect of friction. It was fumed out that the relationship of the stress and strain using the tapered platen was in close agreement with the pure compressive state.

• Journal of Biosystems Engineering
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• v.30 no.5 s.112
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• pp.280-284
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• 2005

Front the production on the farm to the consumer, agricultural products are subject to various physical treatments involving mechanical techniques and devices. It is essential to understand the physical laws governing the response of these biological materials so that the machines, processes, and handling operations can be designed fur maximum efficiency and the highest quality of the end products. A compression test system was developed to test the physical properties of fruits including apple, pear, and peach which may lead to a better understanding of the physical laws. The test system consisted of a digital storage oscilloscope and simple mechanism which can apply quasi-static compression to fresh fruits. Rupture force, energy, and deformation were measured at the five levels of compression speed from 1.25 to 62.5 mm/min for each internal and external tissues. Rupture forces for apple and pear were in the range of 42.2 to 46.2 N and 38.8 to 41.2 N for external and infernal tissues, respectively. Rupture forces fir peach external tissues were in the range of 48.2 to 54.0 N.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.06a
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• pp.15-32
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• 1999

A relationship between stress and stain is very important to design a die to avoid defects of products during semi-solid forming process. Since the liquid will be of eutectic composition in alloys liquid segregation will result in significant or undesirable situation. The materials used in this experiment are A 357. A390, Al2024 alloys that is fabricated by the electro-magnetic stirring process from Pechiney in France. The compression test was performed by induction heating equipment and MTS. In order to prevent the liquid segregation these measured temperature would be useful to control of strain rate during compression test. The liquid segregation is controlled as change of the strain rate and solid fraction during the compression process, The characteristics of flow between solid and liquid phase considering liquid segregation is examined through the above experiments. In the case of medium and high volume fractions of solid the distribution of strain rate is calculated by using compression test data of semi-solid materials (SSM). The thixoforming experiments with the designed die are carried out successfully. The die filling patterns of SSM for variation of die temperature and pressing force have been investigated. The hardness of the thixoformed scroll products is evaluated in terms of the microstructure for each position.

• Journal of Pharmaceutical Investigation
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• v.41 no.2
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• pp.83-90
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• 2011

Main objectives of this study were to investigate the effects of a lubricant, magnesium stearate, as blended in a hydrophilic matrix tablet and to identify significant factors using a tablet ejection force and a swelling property. The characteristics of tablet ejection were evaluated with three different compression forces (30, 40, and 60 MPa) and two controlled factors, amount of magnesium stearate and its mixing time. A hydrophilic model drug (terazosin HCl dihydrate) was regarded as a default factor. Tablet swelling was also evaluated. The optimal amount of PEG compared to PEO was set to be 88.50% w/w. As the amount of magnesium stearate was varied from 0.79% to 2.20% w/w, the amount of PEO and PEG was adjusted to meet the tablet's total weight while maintaining the ratio between the two excipients constant. As the mixing time of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased. As the amount of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased since the increased mixing time and the amount of magnesium stearate induced hydrophobic properties of the matrix tablet more effectively. The ejection force of the tablet increased as a result of increase in the compression force, which means that the breaking of tablet/die-wall adhesion energy was also increased when the compression energy was increased. The results gavea valuable guide how to choose suitable amount of the lubricant with processing conditions for the development of hydrophilic matrix formulations.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.425-430
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• 2003

The material properties of rubber was determined by the experiments of uniaxial tension, uniaxial compression, planer tension, equi-biaxial tension and volumetric compression. In compression test, it is difficult to obtain the pure state of compression stress and strain due to friction force between the specimen and compression platen. In this study, the stress and strain data from the equi-biaxial tension test were converted to compression stress and strain and compared to a perfect state of simple compression data when friction was zero. The compression test device with the tapered platen was proposed to overcome the effect of friction. It was turned out that the relationship of the stress and strain using the tapered platen was in close agreement with the pure compressive state.