• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.36 no.1
• /
• pp.155-162
• /
• 2020

The aim of the research is to investigate the fundamental properties and heat of hydration reducing performance of the fly ash incorporated concrete mixture when the coal gas slag (CGS) from integrated gasification combined cycle (IGCC) is used as fine aggregate. From the results of the experiment, the workability was generally increased and the air content was decreased up to one to four percent with increasing the replacing ratio of CGS to fine aggregate. The compressive strength was similar or increased within five percent to the Plain mixture when the CGS was used as a fine aggregate. When the CGS and fly ash were used same time, the heat of hydration reducing performance was improved than single using cases either CGS or fly ash. Based on the results, for the concrete mixture using CSG as a portion of the combined fine aggregate, the general properties were improved and heat of hydration was decreased approximately 16 % when the fly ash was replaced 30 % to cement and the CGS was replaced less than 50 % to fine aggregate.

• Journal of Surface Science and Engineering
• /
• v.34 no.6
• /
• pp.531-536
• /
• 2001

Co-22 %Cr alloy films are promising for high-density perpendicular magnetic recording media with their perpendicular anisotropy and large coercivity of 3000 Oe. We observed that a self organized nano structure (SONS) of fine ferromagnetic Co-enriched phase and paramagnetic Cr-enriched phase appears inside the grain of Co-Cr magnetic alloy thin films at the elevated substrate temperature after do-sputtering. The periodic fine Co-enriched phase and Cr-enriched phase is the plate shape of 80 (equation omitted)-wide and 1000 (equation omitted)-long. Cr-enriched phases are located at the center of grains. We prepared 5000 (equation omitted) -thick Co-22 %Cr films on polyimide substrate with varying substrate temperature of $ 30^{\circ}C$, $ 150^{\circ}C$ ,200 $^{\circ}C$, $300^{\circ}C$, and $400^{\circ}C$, respectively. A transmission electron microscope equipped with energy dispersive X-ray analyzer is employed to observe the microstructure of each samples after Co-enri-ched phase are etched selectively. The self organized nano structure of Co-enriched and Cr-enriched lamellar is observed above the substrate temperture of $150^{\circ}C$. No compositional change is observed with substrate temperature. The compositional phase separation in self organized structure becomes clear as the substrate temperature increases. Our results implies that the self organized nano structure in Co-22 %Cr film is ideal for ultra high density recording media by recording selectively on Co-enri-ohed phase.

• Applied Microscopy
• /
• v.52
• /
• pp.6.1-6.5
• /
• 2022

We examined the morphology of the fertilized egg and the fine structure of fertilized egg envelopes of Poropanchax normani belonging to the family Poeciliidae, also known as Norman's lampeye using light and electron microscopes. The fertilized eggs with narrow perivitelline space were found to be spherical and demersal, additionally containing small oil droplets in the vitelline membrane. Further, a bundle of adhesive filaments was observed to be present on one side of the fertilized egg. These filaments possessed remarkably high elasticity and were approximately 1-3mm in length. The size of the fertilized egg was determined to be about 1.49 ± 0.07mm (n=30). The outer surface appeared smooth, and adhesive filaments originating at different location of the surface of the envelope were found to be distributed around the egg envelope and were joined together to form a single long bundle in scanning electron microscopic observation. A peak-like structure formed of several straight wrinkles was observed around the micropyle. However, the complete structure of the micropyle could not be studied due to the depth at which it was located. Additionally, the total thickness of the egg envelope was ascertained to be approximately12.5-14.5㎛. The egg envelope consisted of two distinct layers, an outer electron dense layer and an inner lamellar layer, further consisting of 10 sublayers of varying thicknesses. Collectively, it was observed that the morphological characteristics of the fertilized egg, fine structures surrounding the micropyle, outer surface, adhesive structure consisting adhesive filaments, and sections of fertilized egg envelope displayed species specificity.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.333-336
• /
• 2002

In this study, to achieve the optimal conditions for mechanical hyper-fine pattern fabrication process, deformation behavior of the materials during indentation was studied with numberical method by ABAQUS S/W. Polymer (PMMA) and brittle materials (Si, Pyrex glass) were used as specimens, and forming conditions to reduce the elastic restoration and bur was proposed. The indenter was modeled a rigid surface. Minimum mesh sizes of specimens are 1-l0nm. The result of the investigation will be applied to the fabrication of the hyper-fine pattern and mold.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2007.10a
• /
• pp.356-359
• /
• 2007

Continuing improvements in integrated circuit chip density and functionality have mostly contributed toward a very large-scale integrated circuit(VLSI) and display device. In order to test (pass or fail) all of the high integrated semiconductor chip and display device, fine pitch probes are used. Fine pitch probes are manufactured by electroforming process of a Ni alloy in an electrolytic bath. In this paper, we expect that the electric field in bath with the Finite Element Method and applying the FEM result. So, we can obtained the probes that have high aspect ratio of 10 : 1

• The Journal of the Korea Contents Association
• /
• v.16 no.5
• /
• pp.290-297
• /
• 2016

This study analyzed the features of the nodules requiring a fine needle aspiration, which were found in thyroid ultrasonography of the employee health check-up examinees. Based on the fine needle aspiration results, over 1 cm nodules or those implying malignancy on the ultrasonography were categorized into the 1st group. Whereas, regardless of the size the fine needle aspiration results implying malignancy on the ultrasonography were categorized into the 2nd group. In the 1st group, 15.8% were malignant, and in the 2nd group, 28% were malignant. The findings implying malignancy were statistically significant. However, even though the nodules were larger than 1 cm, when the nodules were not accompanied by a high risk factor and showed a spongiform structure in the ultrasonographic results, most of them were benign, and a fine needle aspiration was not required. The ultrasonographic findings are important rationales in making a decision on whether or not a fine needle aspiration is required for thyroid nodules. Currently, the fine needle aspiration for thyroid nodules is commonly performed when the size of the nodule is larger than 1 cm, even though it has a spongiform structure, to relieve the patient's anxiety. However, if ultrasonographic findings of thyroid are correctly understood in differentiating malignant from benign nodules, unnecessary fine needle aspiration can be avoided.

• The Journal of the Korean life insurance medical association
• /
• v.18
• /
• pp.7-8
• /
• 1999

• 한국전자현미경학회:학술대회논문집
• /
• 2007.05a
• /
• pp.49-50
• /
• 2007

• 한국전자현미경학회:학술대회논문집
• /
• 2007.05a
• /
• pp.59-60
• /
• 2007

• 한국전자현미경학회:학술대회논문집
• /
• 2007.05a
• /
• pp.63-64
• /
• 2007