• Fashion & Textile Research Journal
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• v.3 no.4
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• pp.373-377
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• 2001

When the polyester/cellulosic fiber mixed fabrics were treated with sodium hydrogensulfate for burn-out printing, it is examined how the effects of process conditions as concentration of acid, fixation temperature and fixation time act onto the properties of the polyester ground fabrics. The print paste, indalca solution, was mixed with sodium hydrogensulfate and glycerine, and then screen-printed on the fabrics. The properties of the polyester ground fabrics after removing away the cellulosic fibers were investigated. The yellowness index and the breaking load of polyester ground fabrics affected by the process conditions, especially dry heat fixation temperature.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.333-338
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• 2003

Polymeric composite structures used in ground transportation applications such as the carbody of tilting train may be exposed to a ground environmental conditions during long-term missions. In this study, the degradation of mechanical and physical properties of graphite/epoxy composite and glass fabric/phenol composite under ground environmental conditions was investigated. Accelerated environmental conditions of ultraviolet radiation, temperature, and moisture were considered. Several types of specimens were used to investigate the effects of environmental conditions on mechanical properties of the composites. Also, storage shear modulus, loss shear modulus, and tan 8 were measured as a function of exposure times through a dynamic mechanical analyzer. Finally, composite surfaces exposed to environmental conditions were examined using a scanning electron microscope.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.78-79
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• 2013

As a part of study to maximize the amount used of the ground granulated blast-furnace slag, the study deals with setting properties of paste that is mixed the ground granulated blast-furnace slag with CaO-Al₂O₃ based inorganic blinder. The results of the experiment show that the setting time is most fast in the mix of 25% rate of CaO-Al₂O₃ based inorganic blinder. It is generally needed 2 hours for work time in precast concrete products. In this study, this requirement is achieved when using the retarder of 0.5%.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.103-108
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• 1999

This paper describes development of a new automated real-time system which preforms measurement data reduction and management, geotechnical backanalysis, and feedback design for embankment construction on soft ground. Such a system can be an effective, useful and economical tool for managing a large site development on soft ground. The system consists of data base system to characterize soil properties and identify instrumentation, analysis system for ground behavior and stability coupled with automatic monitoring system, and feedback design system which is a new technique to reflect the analysis of measured ground behavior against original design.

• Journal of the Korean Solar Energy Society
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• v.34 no.2
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• pp.66-72
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• 2014

Ground source heat pump system can achieve high efficiency of performance by utilizing annually constant underground temperature to provide heat source for space heating and cooling. Generally, the depth of constant-temperature zone under the ground depends on surface heat flux and soil properties. The deeper the ground heat exchanger is installed, the higher the heat exchange rate can be acquired. However, in order to optimally design the system, it is necessary to consider both the installation cost and the system performance. In this study, performance analysis of ground source heat pump system according to the depth has been conducted through the case study.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.155-160
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• 2005

To purpose of this research is to develop the numerical model for simulating performance of ground heat exchanger with high prediction accuracy. This paper describes the development of a numerical model that simulates the heat transfer between ground and circulation water in ground heat exchanger. Furthermore, we propose the estimating technique of soil properties, such as thermal conductivity, heat capacity and hydraulic conductivity, based on ground investigation. Comparison between experiment and numerical analysis based on the model developed above was conducted under the condition of the experiment in 2004. The result of analysis agreed well with the experimental result.

• Earthquakes and Structures
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• v.3 no.5
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• pp.629-647
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• 2012

Multiple acceleration sequences of earthquake ground motions have been observed in many regions of the world. Such ground motions can cause large damage to the structures due to accumulation of inelastic deformation from the repeated sequences. The dynamic analysis of inelastic structures under repeated acceleration sequences generated from simulated and recorded accelerograms without sequences has been recently studied. However, the characteristics of recorded earthquake ground motions of multiple sequences have not been studied yet. This paper investigates the gross characteristics of earthquake records of multiple sequences from an engineering perspective. The definition of the effective number of acceleration sequences of the ground shaking is introduced. The implication of the acceleration sequences on the structural response and damage of inelastic structures is also studied. A set of sixty accelerograms is used to demonstrate the general properties of repeated acceleration sequences and to investigate the associated structural inelastic response.

• International Journal of Air-Conditioning and Refrigeration
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• v.16 no.4
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• pp.109-116
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• 2008

Ground temperature restoration characteristics are the crucial factors to evaluate whether a ground source heat pump system can keep long time steady operation. They are mainly dependent on soil thermal properties, layout of pile group, operation/shutoff ratio, cooling/heating load, thermal imbalance ratio and so on. On the one hand, several types of vertical pile foundation heat exchangers are intercompared to determine the most efficient one by performance test and numerical method. On the other hand, according to the layout of pile group of a practical engineering and running conditions of a GSHP system in Shanghai, the temperature distribution during a period of five years is numerically studied. The numerical results are analyzed and are used to provide some guidance for the design of large-scale GSHP system.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.423-428
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• 2007

This study was performed to construct a geothermal data base about thermal conductivity of ground heat exchanger and thermal properties of grouting material which used to refill the borehole. We have acquired geothermal data sets from 39 sites over wide area of South Korea except to Jeju island. From data analysis, the range of thermal conductivity is 1.5$\sim$4.0 W/mK. It means that thermal conductivity varies with grouting material as well as regional geology and ground water system.

• Journal of Pharmaceutical Investigation
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• v.16 no.1
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• pp.36-41
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• 1986

The ground mixtures of ketoprofen with chitin or chitosan were prepared by grinding in a ball mill to increase the dissolution rate. The ground mixture showed a faster and more enhanced dissolution rate than the physical mixture or intact ketoprofen. The X-ray diffraction peaks indicated the production of the amorphous form of ketoprofen in the ground mixture. An interaction, in the ground mixture, such as association between the functional groups of ketoprofen and chitin or chitosan might occur in the molecular level. The endothermic peak due to the fusion of ketoprofen disappeared in the ground mixture indicating the different thermal property. The co-grinding technique with chitin or chitosan provided a promising way enhancing the dissolution rate of practically insoluble drug.