• Journal of the Korean Society of Safety
• /
• v.4 no.1
• /
• pp.91-98
• /
• 1989

Today, the conception of building architecture is changing the conception that it is a kind of product and the operator of construction try to produce excellent building through developing efficiency and materials of building component. This study improves the problematic point of the extenor tile setting, through making on experiment on the method of it and purposes doing to do the exterior tile setting of good quality as it selects out of the most conformable the method. The experimental materials choose the tile of 60$\times$108mm size which are using frequently in the exterior tile setting and mortar is made from sand of Han river and potland cement, which apply the volume mixing of the ratio 1：3. The water cement ratio (W/C)is made up 62％ The methods of tile setting utilise the method of the tile setting and laying the method of the tile improved setting and laying, the method ol the pressing adhesion, the method of the improved pressing adhesion and the method of setting adherent (the method of VIBRATOR).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.11a
• /
• pp.65-68
• /
• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.644-645
• /
• 2006

TiC-and Ti(C,N)-based cermets are excellent in semi-and final finishing of work piece during cutting operations. Typical microstructure of the cermets is a core/rim structure. The undissolved Ti(C,N) cores contribute to their high hardness while the rim phases, (Ti,M1,M2)(C,N)-type solid solutions, play great roles in enhancing the toughness. In this paper, various ultrafine pre-mixed MeC-Ni powders were synthesized and the powders were sintered or hot pressed after mixing in order to control the size and volume fractions of core and rim phases in the system. This paper will present the factors determining the microstructure along with mechanical properties.

• Journal of Sensor Science and Technology
• /
• v.24 no.2
• /
• pp.88-92
• /
• 2015

In order to study the semi-conductive characteristics of carbon black-filled ethylene-propylene-diene monomer (EPDM) composite film, which is used for measuring occlusal force, composite samples with volume ratios of carbon black to EPDM ranging from 30% to 70% were prepared. The process of making a composite film consists of two steps, which involve the preparation of a slurry composition and the fabrication of a thin film using solution casting and a lamination process. To prepare the slurry composition, we dispersed carbon black nanoparticles into an organic solvent before mixing with an EPDM solution in toluene. The mechanical and electrical properties of the resulting carbon black-filled EPDM film were then investigated, and the results showed that the electrical resistance of a film decreases with the increase in the carbon black content. Furthermore, improved elastic recovery was observed after cross-linking the EPDM.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.20 no.5
• /
• pp.327-333
• /
• 2008

The purpose of this study is to develop a paddle-type dryer and to commercialize the dryer, in which mixing and drying can be done simultaneously. According to a performance test, a newly-designed paddle-type dryer can dry Chitosan salt to a low moisture contents below 0.3%. Also the newly-designed dryer can dry air pollution materials, because the dryer can operate in a closed system. The economic efficiency of a newly-designed system and an existing system was compared in a performance test. As a result, the economic efficiency of a newly-designed system was higher than an existing system. In conclusion, it is thought that the newly-designed system has a high commercial value.

• Korean Journal of Plant Resources
• /
• v.11 no.3
• /
• pp.358-362
• /
• 1998

This study was carried out to examine the effect on the contents of dietary fiber, mechanical properties, and sensory quality of bread contained with 10% of high-fiber Camellia (Camellia japonica L.) seed flour. Bread added by dietary fiber was the contents of moisture, protein and ash higher than control bread, while the contents of lipid lower than that of control bread. The high-fiber with Camellia seed flour contained 8.6% soluble dietary fiber, 43.7% insoluble dietary fiber, and 52.3% total dietary fiber. The ratio of insoluble dietary fiber/soluble dietary fiber in the high-fiber with Camelia seed flour was 5 times. Bread with the addition of dietary fiber contained 6.9% total dietary fiber. With the addition of dietary fiber, water absorption , mixing time loaf weight, and hardness increased, but the loaf volume decreased . The sensory quality on bread added by dietary fiber was somewhat low in color, appearance, crumb texture, mouthfeel, flavor and overall preference was higher than that of control bread.

• Journal of Ceramic Processing Research
• /
• v.13 no.spc1
• /
• pp.145-148
• /
• 2012

Spherical silica aerogel powders were fabricated via an emulsion polymerization method from a water glass. A water-in-oil emulsion, in which droplets of a silicic acid solution are emulsified with span 80 (surfactant) in n-hexane, was produced by a high power homogenizer. After gelation, the surface of the spherical silica hydrogels was modified using a TMCS (trimethylchlorosilane)/n-hexane solution followed by solvent exchange from water to n-hexane. Hydrophobic silica wet gel droplets were dried at 80 ℃ under ambient pressure. A perfect spherical silica aerogel powder between1 to 12 ㎛ in diameter was obtained and its size can be controlled by mixing speed. The tapping density, pore volume, and BET surface area of the silica aerogel powder were approximately 0.08 g·cm-3, 3.5 ㎤·g-1 and 742 ㎡·g-1, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.11a
• /
• pp.102-103
• /
• 2020

In this study, the effect of the change in the cement contents on the basic properties of the concrete and the estimation of the cement contents of hardened concretes using the hydrochloric acid melting heat. As a result of the study, as the cement contents increased, the fluidity and compressive strength increased, and there was no significant difference in the air contents and the unit volume mass. In addition, it showed a high correlation when compared with the estimated cement contents derived using the hydrochloric acid melting and the cement contents at the time of mixing. Therefore, it is considered that the hydrochloric acid melting is possible as a method of estimating the cement contents of concrete.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.05a
• /
• pp.116-117
• /
• 2021

This study examined basic mechanical properties by developing eco-friendly soil concrete using Masato particulate matter treated as waste. Experiments show that DG10 satisfies the compressive strength criterion, but for DG20, the criterion was not reached. As the mixing volume of Masato particulates increased, the compressive strength and slump decreased, and in the case of the compression strength test after freezing and melting, it was found that the standards were not met.

• Journal of Bio-Environment Control
• /
• v.21 no.3
• /
• pp.213-219
• /
• 2012

Improving the physico-chemical properties of used media by mixing ratio of new plug media (NPM), used plug media (UPM) and perlite is necessary to improve seedling quality. In this study, five treatments were designed to investigate mixing ratio of UPM and NPM by ratio of volume 0 : 100, 25 : 75, 50 : 50, 75 : 25, 100 : 0, respectively. On the other hand, nine treatments were designed to investigate of perlite volumes were added to UPM and mixed media (UPM : NPM (50 : 50)) with 0, 5, 10, and 20% of ratio volume. The physicochemical properties of all mediums and their effect on growth response of tomato and cucumber seedlings were determined. The result indicates that physical properties was improved when NPM was mixed with UPM and at mixed ratio of volume 50 : 50 (v : v) has similar pore spare, bulk density and water retention to NPM. Seedling quality of tomato and cucumber in mixed media (50 : 50) are better than other mixed ratio and similar to NPM. Addition perlite to UPM and mixed media 50 : 50 (v : v) increased the pore space and water retention. Physical properties such as particle density, pore space and bulk density were increased when perlite volume increased. However, the best of seedling quality was observed by the addition at 10% volume of perlite. These results suggested that optimum of mixed ratio for recycled used media is new media and used media 1 : 1 mixed.