• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.195-201
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• 1997

The present paper describes the effect of dry mixed grinding on kaolinite-aluminum trihydroxide mixture with a planetary ball mill before sintering and its influence on mullite formation during sintering. The size reduction of the mixture is market in the early stage of grinding and the obtained fine particles agglomerate subsequently with an increase of grinding time. The crystal structure of the mixture is collapsed easily into an amorphous one by planetary ball milling, of which amount increases with an increase of grinding time. Only mullite phase except for anatase as an inherent impurity in kaolinite appeared in the sintered body of the mixtures with mixed grinding as relatively lower temperature 1523K, while corundum, cristobalite, and Al-Si spinel phases, besides mullite were formed in the sintered body of the mixture without mixed grinding. Therefore, the mixed grinding treatment is very effective to improve the homogeneous mixing and disp-ersion of the mixture of raw materials on a micro scale and to decrease the thermal decomposition tem-perature by crystal structure change of them so as to obatin direct preparation of mullite with high purity at relatively low temperature.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.8
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• pp.741-751
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• 2000

To achieve high performance by exploiting instruction level parallelism aggressively in superscalar processors, it is necessary to overcome the limitation imposed by control dependences and data dependences which prevent instructions from executing parallel. Value prediction is a technique that breaks data dependences by predicting the outcome of an instruction and executes speculatively its data dependent instruction based on the predicted outcome. In this paper, a hybrid value prediction scheme with dynamic classification mechanism is proposed. We design a hybrid predictor by combining the last predictor, a stride predictor and a two-level predictor. The choice of a predictor for each instruction is determined by a dynamic classification mechanism. This makes each predictor utilized more efficiently than the hybrid predictor without dynamic classification mechanism. To show performance improvements of our scheme, we simulate the SPECint95 benchmark set by using execution-driven simulator. The results show that our scheme effect reduce of 45% hardware cost and 16% prediction accuracy improvements comparing with the conventional hybrid prediction scheme and two-level value prediction scheme.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.236-242
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• 2004

The critical micelle concentration (CMC) and the counterion binding constant (B) in a mixed micellar state of the Dodecylpyridinium chloride (DPC) with the Cetyldimethylethylammonium bromide (CDEAB) at 25$^{\circ}C$ in aqueous solutions of n-butanol were determined as a function of ${\alpha}_1$ (the overall mole fraction of DPC) by the use of electric conductivity method. Various thermodynamic parameters (($X_i,\;{\gamma}_i,\;C_i,\;a^M_i,\;{\beta},\;and {\Delta}H_{mix})$were calculated by means of the equations derived from the nonideal mixed micellar model. The effect of n-butanol on the mixed micellization of the DPC/CDEAB mixtures has been also studied by analyzing the measured and calculated thermodynamic parameters (CMC, B 및 $;{\Delta}G_o\;^m$).

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.413-420
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• 2003

To explore the effective treatment methods for waste food generating malodor compounds, mixed microorganisms (MM) capable of deodorizing of domestic animal waste were applied using household composting box. The mixture of 5 kg whole chips as a bulk agent, 2 kg MM and 1 kg of waste food were input into the compost reactor and agitated. Waste food was supplemented every 24 hours. As the results, the composting volume was stable at 13∼14 L for 10 days. In the initial compost process with MM, the pH and temperature were increased more quickly than that of without MM. Also, the conductivity recognized as a barometer of compost was increased from 0.2 to 2.4 mS/cm that was higher than 1.3 mS/cm of without MM, for 10 days. The malodor compounds generated from waste food treatment such as sulfur compounds and volatile fatty acids were effectively reduced about 90∼l00%, and 70∼80% for 8 days, respectively. The microorganisms growing under the condition of alkaline phase and higher temperature were dominated during the compost Moreover, it was demonstrated that inoculated Bacillus cereus HY15 dominated during the compost results in responsible to the effective treatment of waste food.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.890-897
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• 2021

Since the enforcement of strict regulations on marine fuel oil sulfur content, demand for Low Sulfur Fuel Oil (LSFO) has been increasing. However, as LSFO properties vary greatly depending on the supply timing, region, and supplier, LSFOs can experience problems with sludge formation, blending compatibility, and stability once mixed into storage tanks. This study investigates using ultrasound cavitation effects to improve the quality of LSFOs in storage tanks. For marine gas oil (MGO), the results showed that the relative ratio of high molecular weight compounds to those of low molecular weight decreased after ultrasonic irradiation, due to cavitation-induced cracking of chemical bonds. For marine diesel oil (MDO) and blended oil, a small increase in the relative abundance of low weight molecular compounds was observed after treatment. However, no correlation between time and relative abundance was observed.

• Journal of the Korea Institute of Building Construction
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• v.9 no.5
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• pp.127-133
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• 2009

It is important to increase the strength of binders in order to enhance the strength of concrete. However, when the mineral admixture used for high strength concrete is incorporated individually, its dispersibility decreases due to the phenomenon of compaction, which reduces its fluidity and results in insufficient strength being created. To solve this problem, we can pre-mix each binder in advance to disperse a mineral admixture among binders, which will strengthen the fluidity and strength of concrete. Therefore, this study analyzed the properties of high strength concrete depending on the mix method used, to determine the effect of pre-mix cements ranging from W/B 15 to 35%. It was found that the fluidity of pre-mix increased to a level higher than that of individual mix due to its dispersion and ball bearing effect. The air content was slightly decreased from the result of individual mix due to the micro filler effect, which causes fine particles of silica-fume to fill the voids among cement particles, while the setting time of pre-mix was shorter than that of individual mix, because enhanced dispersion of pre-mix affects hydration heat time. The compressive strength of pre-mix increased due to the phenomenon of compaction of gap structure, and the variation of coefficient decreased by 1.69% on average in strength variation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.629-634
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• 2006

Clarified mixed fruit and vegetable (apple, carrot and orange) juices were prepared using different clarification methods including centrifugation, ultrafiltration (UF), and combined treatment with the blend ratio of 1:1:2, 1:2:1, and 2:1:1 (apple, orange and carrot). Effects of clarification methods on the clarification efficacy as well as other quality parameters were investigated. Clarification was improved with increase in centrifugation speed but was less affected by lowering temperature. Ultrafiltration process was very effective to produce clarified mixed fruit and vegetable juice. Combined treatment did not significantly improve the clarification efficacy since most clarification was already achieved during ultrafiltration process (p>0.05). L*- and b*-values increased while a*-value decreased significantly after clarification regardless of methods in all blend juices (p<0.05). Blend juices with high amount of orange or carrot were better in clarification efficacy and high amount of apple resulted in high turbidity in blend samples.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.155-163
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• 1985

Three pyrazole-herbicides, pyrazolate, pyrazoxyfene and benzophenap, were evaluated for their interaction in controlling barnyardgrass (Echinochloa crusgalli) with two chloroacetamide-herbicides, butachlor and pretilachlor. Percent inhibition of barnyardgrass growth by pyrazolate, pyrazoxyfene, and benzophenap was 44%, 64%, and 0%, respectively, when each was applied at the 1.5 leaf-stage of barnyardgrass at a rate of 3㎏ ai per ㏊ as single treatment, and the benzophenap showed 60% inhibition when it was applied at the coleoptile stage. While the lowest rate controlling the 1.5 leaf-stage barnyardgrasses by 98 to 100% of the butachlor and pretilachlor was 1.5㎏ and 200g per ㏊, respectively. All of the combinations of pyrazolate with butachlor, pyrazoxyfene with pretilachlor, and benzophenap with butachlor have shown synergistic interaction in controlling barnyardgrass on the Chisaka's isobole of 90% growth inhibition as well as on the Colby`s interaction efficacy data; synergism indices were 2.44, 1.62 and 1.52 in order. The dose combinations shown the maximal synergism were 1870g of pyrazolate with 140g of butachlor (1:0.075), 33008 of pyrazoxyfene with 338 of pretilachlor (1:0.01), and 3350g of benzophenap with 520g of butachlor (1:0.15) on the ai/㏊ basis.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.647-654
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• 2005

This study was carried out to investigate the effects of addition of 0.1% rosemary, 0.9% citron peel powder and 0.1% rosemary combination with 0.9% citron peel powder on the POV, TBARS, aerobic microorganisms and nitrite scavenging of emulsion-type sausages. The POV values of sausage containing citron peel powder were significantly lower than those of control at 60 days of storage. The TBARS values of sausage containing rosemary, citron peel powder and rosemary combination with citron peel powder were lower than those of control at 20 and 40 days of storage. The aerobic microorganisms count of sausage containing rosemary, citron peel powder and rosemary combination with citron peel powder were lower than those of control at 20 and 45 days of storage. The nitrite scavenging of sausage containing rosemary were higher than those of control at 20 and 60 days of storage.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.237-243
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• 2020

Coffee is one of the most widely consumed beverages in the world, and sword bean (Canavalia gladiata, SB) reportedly possesses various biological activities. Therefore, in this study, to reduce caffeine intake and improve coffee function, SB was selected as a supplementary material for blending coffee. The antioxidant and anti-inflammatory activities of coffee with the SB extract at concentrations of 0.1-0.5% (v/v) were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and RAW 264.7 cells, respectively. The DPPH radical-scavenging activity of SB-treated coffee depended on the concentration of the SB extract. In the cell culture experiment, cytotoxicity was not observed at any SB concentration. In addition, the inducible nitric oxide synthesis protein expression as well as the increases in nitric oxide and interleukin-6 expression were effectively inhibited by SB addition to the coffee. These results indicate that SB might be useful as a supplementary ingredient to enhance the caffeinated drink functions.