• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.E
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• pp.60-69
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• 1992

The research significance of the paper is to identify the major properties of synthetic lightweight concrete that are affected by ASR expansion and to determine the extent and magnitude of the loss in these properties. Emphasis is also given to the use of non-destructive testing techniques ; Such as dynamic modulus of elasticity and ultrasonic pulse velocity, to examine whether these methods could be used to identify the initiation of expansion and the internal structural damage caused by ASR.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1599-1604
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• 2012

In general, internal defects, such as shrinkage in casting, cause stress concentration and can be a starting point for cracks. Therefore, it is important to understand the effects of internal defects on the mechanical properties including the impact behavior. This study aim is to evaluate the effects of internal casting defects on the impact performance of Al-alloy castings. Both an experimental method and computational analysis were used to achieve the research objective. The internal defects in the casting were scanned using an industrial CT scanner, and their shape was simplified using ellipsoidal primitives for impact analysis. The good agreement between the experimental and computer simulation results verified the reliability of the proposed computational method for the FEA of casting components with internal defects.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.195-201
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• 2016

The purpose of this study is to find out key factors of successful urban regeneration based on previous studies and relationships between those factors and revisit intention. To draw a conclusion, this study makes surveys including the variables of success factor(External environment factors, Internal environment factors, Internal cultural factors), degree of satisfaction, and degree of revisit intention. And it collects the data from respondents who had been to Gamcheon culture village in Busan. The data is analyzed by applying an exploratory factor analysis and a confirmatory factor analysis. The result of these analysis describes that the Internal environment factors and Internal cultural factors affect the satisfaction degree positively and the degree of satisfaction has positive effects on the revisit intention. The study finds out that unique resource properties should be considered when underdeveloped cities are regenerated. Future study is to generalize the theory through the sampling covered the whole country.

• Tuberculosis and Respiratory Diseases
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• v.63 no.2
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• pp.173-177
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• 2007

Tuberculosis remains as a major public health problem worldwide. In addition to classic pulmonary tuberculosis, tuberculosis may sometimes present atypically. In the case of atypical tuberculosis, the unusual sites and properties that mimic other diseases can lead to a misdiagnosis and therapeutic delay. Abdominal and pharyngeal tuberculosis are uncommon extrapulmonary manifestations of tuberculosis. To the best of our knowledge, a combination of abdominal and pharyngeal tuberculosis with endobronchial tuberculosis has not been reported. We report a case of concurrent abdominal and pharyngeal tuberculosis in a patient with chronic endobronchial tuberculosis mimicking a metastatic malignancy on computed tomography and FDG-PET.

• Journal of Electrical Engineering and Technology
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• v.7 no.6
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• pp.959-964
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• 2012

Internal pressure of vacuum interrupter (VI) is one of the most important parameters in VI operation and may increase due to the outgassing from the materials inside VI or gas permeation through metal flange or ceramic vessel. The increase of the pressure above a certain level leads to the failures of switching or insulation. Therefore, an effective pressure check of VI is essential and an analysis of partial discharge (PD) characteristics is an effective monitoring method to identify the degree of the internal pressure of VI. This paper introduces a research work on monitoring the internal pressure of VI by analyzing PDs which were measured using a capacitive PD coupler. The authors have developed cost effective capacitive coupler based on the ceramic material that has an excellent insulation properties and the main component of the capacitive coupler is made by SrTiO3. Detectable internal pressure range and distinguishability of the internal pressure of VI were investigated. From the PD tests results, the internal pressure range, from $10^{-2}$ torr to 500 torr, can be monitored by PD measurements using the capacitive coupler and PD inception voltage (PDIV) follows the Paschen's law. In addition, rise time of PD pulse at 13.2kV decreases with the increase of the internal pressure of VI.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.22-31
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• 2020

In this study, rice straw and bagasse are used as raw materials to produce binderless particleboard (BPB). This study aims to evaluate the mechanical and physical properties of BPB. We identify the raw material that would be better for the production of BPB from the viewpoint of their basic properties. The BPBs are made from rice straw, bagasse, and combinations of both in ratios of 50:50 and 40:60, respectively. The modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) strength, water absorption, and thickness swelling properties of the different BPBs are determined and compared. Results showed that all the properties are significantly influenced by the type of particles or particle combinations in the BPB. BPBs made from bagasse alone have the highest MOR, MOE, and IB mean values, whereas BPBs made from rice straw alone exhibit the lowest MOR, MOE, and IB values. Meanwhile, BPBs made from a combination of rice straw and bagasse at 40:60 ratio by weight have the second highest values for properties such as MOR, MOE, and IB, followed by BPBs made from a combination of rice straw and bagasse at 50:50 ratio by weight.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.10
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• pp.766-772
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• 2002

In this investigation, experimental attempts were made to observe and determine the variations in elastic and damping properties of the PVC depending on the amounts of MBS added to the mixture, PVC/MBS, and also on the thicknesses of the specimens. An acoustic resonance technique was used for the tests In this investigation. It serves as a method to characterize properties of materials set in vibrational motions, which is initiated by low level stresses generated by externally supplied acoustic energy. Substantial variations were observed in the test results with the addition of the MBS to the PVC. It was found that the magnitudes of elastic constants decrease while the damping capacity improve when MBS rubber was added in the range up to 9 phr.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.49-51
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• 1989

The effect of Mo elenent and annealing condition on the magnetic properties were investigated in Fe$_{80}$B$_{12}$Si$_{8}$ amorphous alloy. With increasing Mo contents, soft magnetic properties were improved by decreasing coercive force and increasing maximum permeability. These improvements were attributed to the decreasing of magnetostriction by Mo addition. The annealing treatment also improved the soft magnetic properties of (Fe$_{1-x}$ Mo$_{x}$)$_{80}$ B$_{12}$ Si$_{8}$ amorphous alloys. It could be thought that these improvements were ascribed to the relaxation of internal stress.nal stress.ess.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.1
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• pp.15-23
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• 2000

Effect of fixation methods on the flame retardant(FR) and performance properties of MDPPA/HMM treated cotton fabrics were studied. Combination of three different fixation methods - premercerization, swelling agent treatment, pad dry cure fixation, and wet fixation - were applied to flame retardant finish of cotton with MDPPA/HMM. As a result, an increase in internal volume of cotton fiber by pre-mercerization and addition of swelling agent, and wet fixation increased %add-on of FR agent improving FR efficiency and wash fastness. Tensile strength of MDPPA/HMM treated cotton fabrics by wet fixation and swelling agent were slightly decreased, but that of premercerized cotton was improved. Wet fixated fabric showed lower bending rigidity and better compressional properties which improved fabric hand. Retention of swelling ability of cotton treated with MDPPA/HMM improved moisture absorption properties.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.120-121
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• 2006

Magnetic properties of nanostructured materials are affected by the microstructures such as grain size (or particle size), internal strain and crystal structure. Thus, it is necessary to study the synthesis of nanostructured materials to make significant improvements in their magnetic properties. In this study, nanostructured Fe-20at.%Co and Fe-50at.%Co alloy powders were prepared by hydrogen reduction from the two oxide powder mixtures, $Fe_2O_3$ and $Co_3O_4$. Furthermore, the effect of microstructure on the magnetic properties of hydrogen reduced Fe-Co alloy powders was examined using XRD, SEM, TEM, and VSM.