• International Journal of Highway Engineering
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• v.13 no.1
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• pp.169-175
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• 2011

Strength is one of the very important factors to evaluate the physical properties of concrete. Aggregate forms the most parts in concrete. Cement as a binder in concrete is also closely related to strength. This experiment was tested to understand the effect of the characteristics of aggregate and cement on the relationship between concrete compressive strength and Shear Wave velocity. It was experimented by the different types of cement and maximum coarse aggregate sizes. Type I cement and rapid setting cement was used. Aggregates from three different regions were used. Aggregate of 19mm and 13mm maximum coarse aggregate sizes was used for grading. The relationship between compressive strength and Shear Wave velocity was tested under the condition of same mixture. LA wear test was used to quantify the characteristics of aggregate. As a result, the relationship between concrete compressive strength and Shear Wave velocity was affected by the types of cement, but regular relationship was appeared regardless of types of aggregate, grading and abrasion ratio.

• Composites Research
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• v.26 no.5
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• pp.328-333
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• 2013

In this study, bone plate made of glass/polypropylene composite material which was applied to an artificial bone was tested to check the service ability under fatigue loading. To check serviceability of composite bone plates fatigue test was carried out considering changes in the moisture absorption rate, locking position of screws and loading condition. Test results showed that all the tested specimens had the fatigue life more than one million cycles which was much higher fatigue life than the expected value of 650,000 cycles. Screw position was not critical impact on the deformation of the fracture site. In this paper, the mechanical performance of the glass/polypropylene composite was verified by fatigue test under various water absorption conditions, and this result may give useful information on the design of composite bone plate.

• Journal of Soil and Groundwater Environment
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• v.16 no.2
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• pp.52-60
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• 2011

Although facilities for the passive treatment of AMD (Acid Mine Drainage) are currently operating in Korea, their removal efficiency for heavy metals is relatively low in average (only 80%). Passive treatment system is composed of oxidation tank, SAPS (Successive Alkalinity Producing System), and wetland. In the treatment system adopted in korea, SAPS (Successive Alkalinity Producing System) plays a major role to remove about 65% of heavy metals through a precipitation. However, the efficiency of SAPS is limited due to the use of mushroom compost (MC) as a organic material and of limestone as a neutralizer. Therefore, this research was performed to search for alternative organic materials through the field test. We tested two types of mixed organic materials: 1) cow manure and spent oak (herein, CO) and 2) cow manure and sawdust (herein, CS). For comparison mushroom compost (herein, MC) was also tested. The result showed that the average Fe removal efficiency was 91.38% with CO, 85.19% with CS, and 91.58% with MC. Thus, CO can be effectively used as an alternative of MC in the SAPS system for heavy metals removal.

• Journal of Environmental Science International
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• v.15 no.4
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• pp.305-310
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• 2006

The color and structure of urban constructions is a factor of urban landscape and shows their characteristics. Hence the modern buildings deal with their materials and external appearance as an important factor, making up the urban image. But it was nearby impossible to evaluate the value of visual landscape with objective measuring method. Most of all, it depends on the subjective estimation of a few talented or high educated experts with a sense of beauty. Such kinds of estimation can in some cases include arbitrary interpretations. In relation to this kind of problems, it is tried here in this study to analyse the human response of brain wave pattern (EEG) with use of SD method, while the tested persons watch the urban landscape scenery constructed in a visual reality. The tested persons were 20 adult male and female with no color blindness and intact cognitive function. Light source with color filter was used for color environment in a dark soundproof chamber. The signal of EEG is analysed digitally and grouped into the ${\alpha}$ and ${\beta}$ waves. The result showed that relative power of ${\alpha}$ wave ratio increased in the natural landscape scenery with blue and green color. From these results it was possible to evaluate the human response, which is affected by urban and natural color and structure stimulation and it might be useful as an indicator of visual cognition amenity toward the design of urban construction environment.

• KSBB Journal
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• v.18 no.2
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• pp.117-121
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• 2003

The study was carried out to determine the effect of storage property and qualities on soybean sauce and paste by adding different amount of pyroligneous liquor obtained by sujpercritical fluid extraction(SFE). Purified pyroligneous liquor obtained by SFE at 4$0^{\circ}C$/110 bar contained p-cresol, o-cresol and m-cresol food sterilizers, but no toxic substances such as tar, scorched, furfuraland and monophenol. Thus pyroligneous liquor was considered to be suitable as natural food preservative. In case of soybean sauce, pyroligneous liquor was tested to determine the potential of natual food preservative to prevent flim formation on soybean ksauce 15days at 3$0^{\circ}C$. Increasing amounts of purified pyroligneous liquor added to soybean sauce prevented film forming yeasts. In case of paste, pyroligneous liquor was tested to determine the potential of natural food preservative to inhibit browning on paste 60 days at 3$0^{\circ}C$. Purified pyroligneous liquor added to paste inhibited brown pigment. As a result, purified pyroligneous liquor offered a promising way of improving the quality and storage property of soybean sauce and paste.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.7
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• pp.459-466
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• 2014

In this paper, we suggest an efficient image processing method for fast paper currency counting with pattern recognition. The patterns are consisted of feature data in each note object extracted from full reflection image of notes and a general contact image sensor(CIS) is used to aggregate the feature images. The proposed pattern recognition algorithm can endure image variation when the paper currency is scanned because it is not sensitive to changes of image resulting in successful note recognition. We tested 100 notes per denomination and currency of several countries including Korea, U.S., China, EU, Britain and Turkey. To ensure the reliability of the result, we tested a total of 10 times per each direction of notes. We can conclude that this algorithm will be applicable to commercial product because of its successful recognition rates. The 100% recognition rates are obtained in almost cases with exceptional case of 99.9% in Euro and 99.8% in Turkish Lira.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.1-8
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• 2001

The 90% methanol extracts of eight magnoliaceae plants were collected and tested the cytotoxicity against SK-OV-3 and SiHa cells. Also six pure compounds such as magnonol, honokiol, dihydroxybiphenyl ether, linodenine, anonaine, asimilobine which were previously isolated from Magnolia obovata Thunb. were evaluated the cytotoxicities and their mechanism study using the Lactate dehydrogenase assay(LDH) and FACScan analysis system. Of the tested six compounds, magnonol, honokiol, dihydroxybiphenyl ether showed high cytotoxicities against human cancer cell lines, SK-OV-3 and SiHa cells. In addition, one of the plausible mechanisms of their antitumor activities suggested that they could induce the early stage of apoptosis. For the quantitative analysis, the methanol extractives were fractionated with chloroform, ethylacetate, $H_2O$ and then the ethylacetate fraction was chromatographed on silica gel using n-Hexane ; Acetone(4:1, v/v) as eluent. This fraction was subjected for the quantitative analysis in the HPLC system. The result suggested that the methanol extractives of Magnolia obovata Thunb. contained with magnonol, honokiol, dihydroxybiphenyl ether, 0.9%, 0.3% and 0.24%, respectively.

• Environmental Mutagens and Carcinogens
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• v.16 no.1
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• pp.13-18
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• 1996

One mechanism of free-radical production by ethanol is suggested to be through the intracellular conversion of XDH to XO by increased ratio of NADH to NAD. The major mechanism for physiological compensation of cytosolic NADH/NAD balance is the malate/aspartate shutfie. Therefore, it is important to develop the method to improve the efficiency of malate/aspartate shuttle in ethanol metabolism. In the present study, various amino acids and organic acid involved in the shuttle were tested for their functional efficiency in modulating shuttle in the ethanol-perfused rat liver. The rate of ethanol oxidation in the liver perfused with aspartate alone or aspartate in combination with pyruvate, respectively, was increased by about 10% compared to control liver, but not in the tissues perfused with glummate, cysteine or pyruvate alone. Though glummate, cysteine and pyravate did not affect the ethanol oxidation significanfiy, they showed some suppresive effect on the ethanol-induced radical generation monitored by protein carbonylation analysis. Among the tested components, aspartate is confirmed to be the most efficient as a metabolic regulator for both ethanol oxidation and ethanol-induced oxidative stress in our perfusion system. These effects of aspartate would result from NAD recycling by its supplementation through the coupled aspartate aminotransferase/malate dehydrogenase reactions and the malate-aspartate shuttle.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.11
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• pp.1622-1629
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• 2002

To enhance isothermal characteristics of glass-farming surface, a rectangular parallelepiped heat pipes was fabricated, tested, and analyzed. The working fluid was sodium and the wall material was stainless steel 304. The dimension of the heat pipe was 210 (L) $\times$ 140(W) $\times$ 92(H)mm. A lattice structure covered with screen mesh was inserted to promote return of working fluid. The bottom side of heat pipe was heated electrically and the top side was cooled by liquid circulation. The temperature distribution at the bottom surface was of major concern and was monitored to determine isothermal characteristics. A frozen start-up of rectangular parallelepiped liquid metal heat pipe was tested. The operating mode of the sodium heat pipe was affected by the temperature of cooling zone, input heat flux, and the operating temperature of heat pipe. The heat pipe operated in a normal fashion as long as the heat flux was over 5.78W/cm$^2$, and the inside wall temperature of condenser part was above 95$^{\circ}C$ The maximum temperature difference at the bottom surface was observed to be 32$^{\circ}C$ when the operating temperature of the heat pipe was operating normally around 50$0^{\circ}C$. The result showed that a sodium heat pipe was very effective in reducing significantly the temperature difference in the glass-forming surface.

• Journal of Marine Bioscience and Biotechnology
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• v.9 no.1
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• pp.8-13
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• 2017

Cost-effective microalgae harvesting methods are necessary for economical production of algal biodiesel. In this study, membranes with various pore sizes and materials were examined for their potentials in application to gravity-filtration of Tetraselmis sp. KCTC12432BP. For this test, 10 L of Tetraselmis sp. culture (2 g/L) was loaded on each membrane and filtration rates were measured. Among the tested materials, a woven cotton fabric showed the fastest water drain rate (0.73 L/hr) without serious cell leakage. Cell density of the concentrates after filtration was 6.8 g/L, indicating 3.4-fold concentration compared with the initial algal culture. The result suggests that the woven cotton fabric could serve as filtration membrane for harvesting Tetraselmis sp. among the tested ones.