• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.2
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• pp.105-111
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• 2023

In this study, the mechanical properties of high-strength concrete according to the substitution rate of NSH(Non-sintered Hwangto) as an alternative material for cement were measured and evaluated. Through UPV(Ultrasonic pulse velocity) analysis, the compressive strength prediction equation was proposed, and the substitution rate of NSH was set at 15 % and 30 %. The evaluation items were compressive strength and UPV, and the curing period was set to 24 hours. In compressive strength and UPV, as the NSH substitution rate increased, lower strength and lower UPV were shown. In addition, the correlation number(R² ) between compressive strength and UPV was 0.99 for NC(Normal Concrete), 0.97 for NSHC(Non-sintered Hwangto Concrete)33-15, and 0.94 for NSHC33-30.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1679-1681
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• 2004

Class-F and B resin-rich type insulating tapes are generally used for the ground wall insulations of respective air-cooled and water-cooled stator windings in larger turbine generators. In this paper, their electrical properties coupled with aging times in higher temperature than designed one in normal condition were experimentally investigated and the results of two comparative tests were presented on the existing class-F resin-rich type tape and a developed one after curing. The resin-rich tapes currently used arc composed of six and a half 3-layer sheets that arc structured with mica paper, the top and bottom supports of it respectively, and the epoxy resin to bind them tightly. The results for breakdown voltage and strength on the cured specimens were presented, which were composed of the unaged, the aged accelerated for one, two, and three thousand hours at 180 $^{\circ}C$. The surface and volume resistivities on them were measured and the results are also presented to make a comparative test for the initial electrical characteristics.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1676-1678
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• 2004

Class-F resin-rich type insulating tapes are generally used for the groundwall insulations of the large turbine generators with air-cooled and hydrogen-cooled stator windings. In this paper, mechanical strength properties degraded over aging time in higher temperature than designed one in normal condition were experimentally investigated and the results of comparative tests were presented on the existing class-F resin-rich type tape and a developed one after curing. The resin-rich insulating tapes with composite material of Mica/Epoxy/support currently were used in this test. The tests for tensile and flexural strength properties were conducted with the specimens which were composed of unaged and the aged specimens accelerated for one, two, and three thousand hours at 180 $^{\circ}C$. The tensional strength was only measured for the unaged specimens and the results are also presented to make a comparative test for their initial mechanical characteristics.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.217-226
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• 2005

This study made member specimen for taking specimen, core with the concrete mixing normal concrete, admixture and conducted the same air curing as field conditions. After performing destructive and nondestructive test by age, estimate expression was suggested by analyzing correlations between compressive strength, rebound number and ultrasonic pulse velocity and the results are as follows. As a result of comparing error rate of existing expressions and this estimation expression, error rate of this estimation is reduced compared to existing expressions and has higher reliability. When conventional concrete expression is applied to admixture concrete, error rate occurs and then this study suggests the estimation expressions depending on types of admixture concrete.

• Journal of Korean Medical Ki-Gong Academy
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• v.15 no.1
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• pp.1-22
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• 2015

Objectives : The purpose of this study is to develop a Gi-Gong method instruction configured with modern motions to suit the Medical curing characteristics of Korean Medicine and improve the development and validation of educational and clinical needs. Methods : We took survey on 33 students after giving 'Yang-Seng Gi-Gong' lectures at Woosuk University School of Korean Medicine in the first semester of the year 2015. Results : 1. Reflection of training goal was 7.75±1.79, which showed that the education was overall interesting, but showed a high satisfaction with the practical rather than the theoretical lectures. 2. General difficulty level was intermediate, but the practice of Hwal-In-Shim-Bang Do-In-Beop from several formulations were evaluated relatively difficult exercise. 3. The propriety of training materials were rated as mostly adequate, but that assessment was relatively less appropriate for the linkage of theory and practice, and that of time allocation and place was a normal level. 4. For the propriety of time distribution, the class of one semester such as the current is rated appropriate by 61% of students. 5. General class participation was 6.34±2.52, then participation in practice than theory lessons were active. On the other hand, Induction training participation and participation appeared to be relatively low correlation, but overall interesting and participation in practice high correlation. Conclusions : The difficulty level of theory lessons is necessary to be adjusted and lecture form will need to continue focusing on practical lessons.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.324-329
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• 2004

SKT is consisted of skullcap radix, knope-sedge radix and trametes mushroom. SKT mixture extract has been used for curing breast cancer and cervical cancer as a folk medicine without any kind of experimental evidence to support the rationales for its clinical use. This study was undertaken to investigate the antitumor effects and toxicity of SKT. Tumor was induced by implantation of B16F10 melanoma cells $(1{\times}10^6\;cells/mouse)$ into abdominal skin in ICR mice and SKT application (5 mg/mouse, p.o.) was initiated 4 days prior to tumor induction and lasted for 42 days. SKT significantly inhibited not only tumor growth but also metastasis of i.v. implanted melanoma cells into lung and showed prolonged life span of tumor bearing mice. The combined theraphy of SKT with doxorubicin was more effective against tumor metastasis into lung. SKT almostly recovered serum SGPT to normal level of galactosamine/LPS-induced hepatitis mice. High dose of SKT did not show any acute side effects. But, in vitro SKT did not inhibit the growth of melanoma cells, which suggests that the antitumor effects of SKT might be menifested by indirect mechanisms.

• The Journal of Korean Medicine
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• v.21 no.3
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• pp.31-39
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• 2000

Objectives : Chekamuiyiin-tang has effects of promoting diuresis, promoting blood circulation, elimating phlegm and strengthening the body's resistance to disease. We experimented with Chekamuiyiin-tang in order to find effects which might possibly cure obesity. Methods : We fed a control group of rats a high fat diet and administered normal saline for 8 weeks. And we fed an experimental group of rats a high fat diet and administered an extract of Chekamuiyiin-tang for 8weeks. Results : The serum total cholesterol level, triglyceride level, free fatty acid level, total lipid level and phospholipid level in the Chekamuiyiin-tang group showed a significant decrease in comparison with the control group. The serum HDL-cholesterol level in the Chekamuiyiin-tang group showed no change in comparison with the control group. The serum LDL-cholesterol level in the Chekamuiyiin-tang group showed a decrease in comparison with the control group, but this result showed no efficacy. The size of the epididymal fat cell and the fat drops area in the hepatic lobule of rats in the Chekamuiyiin-tang group showed a significant decrease in comparison with the control group. Conclusios : According to the above results, Chekamuiyiin-tang has shown to be capable of curing and preventing obesity.

• The Journal of Engineering Research
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• v.8 no.1
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• pp.31-50
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• 2006

Shrinkage may cause cracking in concrete. In practice such cracking must be considered in most concrete applications because, under normal conditions, drying of the concrete is unavoidable, and when drying takes place shrinkage occurs. Cracked concrete is an inferior concrete because it is weaker, more permeable, and more susceptible to chemical attack. The development of the strength of LAC with aging depends on a few factors such as type of the cement, W/C ratio, curing conditions and periods. The higher the strength of LAC, the lower the possibility of shrinkage cracking. Hence, the strength of LAC in the hypocaust system depends to a large extent on the effect of cracking decrease of the antifoaming rate to drying shrinkage in cement.

• Computers and Concrete
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• v.10 no.2
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• pp.95-104
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• 2012

This study uses recycled green building materials based on a Taiwan-made recycled mineral admixture (including fly ash, slag, glass sand and rubber powder) as replacements for fine aggregates in concrete and tests the properties of the resulting mixtures. Fine aggregate contents of 5% and 10% were replaced by waste LCD glass sand and waste tire rubber powder, respectively. According to ACI concrete-mixture design, the above materials were mixed into lightweight aggregate concrete at a constant water-to-binder ratio (W/B = 0.4). Hardening (mechanical), non-destructive and durability tests were then performed at curing ages of 7, 28, 56 and 91 days and the engineering properties were studied. The results of these experiments showed that, although they vary with the type of recycling green building material added, the slumps of these admixtures meet design requirements. Lightweight aggregate yields better hardened properties than normal-weight concrete, indicating that green building materials can be successfully applied in lightweight aggregate concrete, enabling an increase in the use of green building materials, the improved utilization of waste resources, and environmental protection. In addition to representing an important part of a "sustainable cycle of development", green building materials represent a beneficial reutilization of waste resources.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.49-52
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• 2006

Extrusion concrete panel is made by extrusion of high viscosity paste. The high viscosity paste is made by mix of cement, silica, reinforced fiber and thickening agent in the dry mixer and wet mixer subsequently, extrusion in the extruder, and curing in the normal steam curer and high pressure steam curer subsequently. To increase a flexural strength of the panel, it is used inorganic fiber as like asbestos. But it was known that the asbestos was harmful to human being lately, in the domestic area it is restricted usage in the construction materials. So, it is demanded the alternative material for asbestos in the extrusion concrete panel. This study is to investigate that the sepiolite is possible to be the alternative of asbestos. The 3 types of sepiolite is applied to the extrusion concrete panel. To investigate the properties of the panel with sepiolite, it is compared the control with asbestos in the flexural strength, the specific density and the spot compressive strength. From the test results, it was found that the panel with sepiolite B is higher than the control with asbestos in the flexural strength and in the density.