• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.133-139
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• 1997

Conventional concrete mixing method is to put all of the materials simultaneously into a mixer and mix for a required time. However, recently concrete researchers have reported that mixing sequence iufluences the properties of concrete. This study discusses the influence of mixing sequence and partitioning addition of mixing water. Concrete, by method of partitioning addition of mixing water, was found to have substantially stronger strength than conventional concrete with the same water-cement ratio. This means that a higher strength concrete could be obtained by using “Sand Enveloped with Cement”(S.E.C) mixing technique. Both a high bond strength between cement paste and aggregate, and elimination of bleeding both contribute to improving the strength of S. E. C concrete.

• Journal of Technologic Dentistry
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• v.2 no.1
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• pp.17-19
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• 1980

This study was aimed at obtaining a desirable wax pattern for inlay. The method used was to analyze, mix, and heat several kinds of waxes, comparing the temperatures of their components. The result was Type C wax. In type C the amount of paraffin was generally contained(60$\sim$70%) was reduced to 45% and there was mixed 10%-15% of carnauba, which was intended for the wax not to soften readily at low temperatures. The type C has some advantages for general use: handy preparation, high safety, and economy. The inlay waxes commonly used contracted if the temperature fell from 38 to 28, but the contraction of type C was observed to be 0.2%$\sim$0.4% in proportion to the 10 fall. This was more characteristic in mixing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1716-1723
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• 2014

This study was designed to examine the change in physical properties of extruded brown rice-vegetable mix at different pregelatinized brown rice contents and $CO_2$ gas injection. Moisture content, screw speed and die temperature were fixed to 30%, 100 rpm and 60, respectively. $CO_2$ gas injection was adjusted to 0, 300, 600, and 800 mL/min. The content of vegetables (carrot, pumpkin, kale and Angelica keiskei) mix was fixed 5%. Pregelatinized and raw brown rice powder were blended as the ratio of 0/95, 30/65 and 50/45. Specific mechanical energy input decreased as pregelatinized brown rice ratio increased. Expansion index increased and the size and number of pores increased but density decreased with the increasing in $CO_2$ gas injection. Gelatinization degree increased as $CO_2$ gas injection increased. In conclusion, cold extrusion with $CO_2$ gas injection at $60^{\circ}C$ die temperature could be applied for Saengsik (uncooked food) making.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.243-251
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• 1998

Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatic agent. Petroleum ether extract of panax ginseng C.A. Meyer (GPE) and its several fractions (PI-P5) were tested for the evaluation of antigenotoxicity against N-methyl-N-nitrosourea (MNU) and benzo(a)pyrene [B(a)P]-induced micronucleated reticulocytes in mouse peripheral blood. GPE and P2 showed more significant anticlastogenicity than other fractions did. To elucidate the anticlastogenic action mechanism of GPE and P2 against B(a)P, the alteration of B(a)P metabolism was studied. GPE and P2 inhibited B(a)P metabolism in the presence of 8-9 mix and decreased B(a)P-DNA binding in calf thymus DNA with 8-9 mix. They also decreased [$^3H$] MNU induced DNA binding and methylation to 7-methyl guanine and $O^{6}-methyl$ guanine adducts in calf thymus DNA by RPLC analysis. These results suggest that the anticlastogenicity of GPE and P2 on the B(a)P or MNU-induced clastogenicity is due to decrease of DNA binding with B(a)P or MNU, the inhibition of metabolism with B(a)P and the inhibition of methylation in DNA. Therefore, GPE and P2 may be useful chemopreventive agents of alkylating agent like MNU and secondary carcinogen like B(a)P.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.197-208
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• 2014

The present study was conducted to provide basic data for efficient vermicomposting of swine manure by investigating the effect of sawdust mix on growth and reproduction of earthworms, amount of earthworm cast produced, and its chemical composition when mixing swine manure in different levels (0(SSD0), 10(SSD10), 20(SSD20), 30(SSD30), and 40%(SSD40)) with sawdust commonly used as moist control in manure composting. The C/N ratio of the feed and the survival rate of earthworms for the SSD0 treatment (10.19, 35.2%), The C/N ratio of the feed was 11.09-16.44 and increased with higher level of sawdust mixed, and the survival rate of earthworms during the experiment period was 35.2-100%. The number of earthworms was 16.6 in the SSD40 treatment, and young worms were not found in the SSD0 treatment or the treatment with less than 30% sawdust in the mix. The number and the weight of cocoons in SSD30 and SSD40 treatments were found to be in the ranges of 23.8-59.8 and 256-660 mg respectively. The production of earthworm cast and digested amount were higher with the higher level of mixed sawdust (p<0.05), and the C/N ratio of cast increased with the mixed sawdust ratio, being significantly higher ratio in SSD30 and SSD40 than other treatments (p<0.05). Heavy metals content tended to decrease with the mixed sawdust level. To summarize, the higher level of mixed sawdust was associated with improvement in growth and reproduction of earthworms, and 30-40% sawdust mix in particular could result in efficient vermicomposting.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.260-265
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• 1994

High strength concrete(65MPa) was used for construction of the bulk cement storage silo by using sliding form. This paper presents mix design, production, quality control and experience with field application of high strength concrete under cold weather conditions. It is shown to be possible to produce high strength concrete of compressive strength of 50~60 MPa by using high-range water reducer to lower w/c ratio with appropriate quality control.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.251-252
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• 2009

Rheological characteristics of flowable concrete manufactured in domestic products of cement, aggregates, and SP admixtures were investigated by experiments and the predictive model of rheological characteristics of flowable concrete has been newly proposed considering with the effects of the W/C ratio and the dosage of SP admixture.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.261-266
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• 1998

The purpose of this study is to present the reference data on the development of undispersed underwater mortar for augered pile under various replacement ratio of fly-ash. According to the experimental results, when 10% of fly-ash is mixed under mix proportion of 1:1.5(c:s), as strength and shrinkage decrease slightly, whereas fluidity increase, high quality mortar for augered pile can be achieve in case above condition is applied.

• Journal of applied mathematics & informatics
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• v.35 no.1_2
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• pp.147-163
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• 2017

In this paper, we establish the necessary and sufficient Karush-Kuhn-Tucker (KKT) conditions for an optimization problem with difference of set-valued maps under generalized cone convexity assumptions. We also study the duality results of Mond-Weir (MW D), Wolfe (W D) and mixed (Mix D) types for the weak solutions of the problem (P).

• Communications of the Korean Mathematical Society
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• v.32 no.4
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• pp.899-908
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• 2017

We call a sequence $(T_n)_n$ of bounded operators on a Banach space X, BSC-Sequence if it is a Cauchy sequence in the strong operator topology and is uniformly bounded below. We determine conditions under which such sequences has a fixed point.