• Journal of Korean Society of Water and Wastewater
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• v.22 no.1
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• pp.49-63
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• 2008

The objectives of this research were to evaluate the pressurized/the main inlet water flowrate ratio which have been used as the most important parameter for operating the pump diffusion mixer until now, to suggest the alternative operating parameter and the relating criteria if the flowrate ratio was not inadequate. For the objectives of this research, computational fluid dynamics (CFD) simulation was conducted for 21 cases of flowrate ratio in full-scaled pump diffusion mixer. From the results of CFD simulation, the local velocity gradient values were calculated in each case in order to analyze the simulation results in more detail. For verifying CFD simulation, wet test was conducted. The wet test was to measure the factual coagulant dispersion distribution at a distance of 5.4m from deflector. From both results of CFD simulation and wet test, flowrate ratio was inadequate as operating parameter or criteria, on the other hand the pressurized/the main inlet velocity ratio(dimensionless) was useful in predicting the performance of pump diffusion mixer. Also, the injected coagulant could be dispersed evenly in overall cross section on the condition that pressurized/the main inlet velocity ratio(dimensionless) is over at least 20.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.960-972
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• 2017

The objectives of this study was to investigate the properties and stability of the wet noodles added to nanoemulsion as a industrial model system, and in so doing, survey practical applicability in the food industry. In order to test out these objectives, the characteristics and stability of the wet noodles added to nanoemulsion were investigated and their cooking characteristics and capsaicinoids loss were examined. As a result, the test results showed that the findings indicated that the post-cooking loss of capsaicinoids in the wet noodles added to double-layer nanoemulsion covered with chitosan was less than the losses in the wet noodles added to any other noodles. More especially, this demonstrates that the noodle added to double-layer nanoemulsion covered with chitosan scored significantly higher than the others with reference to their cooking properties, color, texture, stability for storage stability, and sensory evaluation. These results show that the findings of this study demonstrated that the noodles added to nanoemulsions could be produced as a food-grade merchandise because they could provide enhanced encapsulation capacity of capsaicinoids and higher acceptability.

• The Korean Journal of Community Living Science
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• v.11 no.1
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• pp.1-8
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• 2000

The characteristics of rice-breads with wet-milling and dry-milling rice-flours were investigated. Rice-breads by wet-milling had a good fermentation than the breads by dry-milling. Also, the fermentation of mugwort rice-breads was lower than those. Rice-breads by dry-milling indicated the higher value in hardness and the lower value in springiness, cohesiveness and chewiness than rice-breads by wet-milling. Also, mugwort rice-breads was the higher value in hardness, springiness, chewiness and the lower value in cohesiveness than rice breads. The test of the sensory characteristics for rice-breads showed that moistness, springiness, chewiness was higher for rice-breads by wet-milling. The sensory characteristics of mugwort rice-breads were lower than those, of rice-breads except the chewiness. Overall quality of rice-breads by wet-milling was higher than that of rice-breads by dry-milling. The overall quality of mugwort rice breads was higher than that of rice-breads by wet-milling, but lower than that of rice-breads by dry-milling.

• Computers and Concrete
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• v.20 no.3
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• pp.311-318
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• 2017

This paper investigates the utilization of waste tyre crumb rubber as the fine aggregate in precast concrete Paving block (PCPB). PCPB's are generally preferred for city roads, pedestrian crosswalk, parking lots and bus terminals. The main aim of this paper is to evaluate the mechanical properties of wet cast PCPB containing waste tyre crumb rubber. The mechanical properties were investigated using a density, compressive strength, split tensile strength and flexural strength tests at 7, 28 56 days according to the IS 15688:2006 and EN1338. The wet cast method was followed for producing PCPB samples. The fine aggregate (river sand) was replaced with waste tyre crumb in percentage of 5%, 10%, 15%, 20% and 25% by volume. All the test results were compared with the conventional PCPB (Without rubber). The test results indicate its feasibility for incorporating waste tyre crumb rubber in the production of PCPB by the wet cast method.

• Journal of Welding and Joining
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• v.2 no.2
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• pp.62-69
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• 1984

In this study, cold crack susceptibility of high strength steel (ABS EH32 Steel) welded zone with shielded metal are welding was investigated by tensile restraint cracking test method. Effects of diffusible hydrogen content on root cracking, lower critical stress, crack initiation and fracture mode, hardness value distribution of welded zone and fractograph were mainly investigated. Following conclusions are made: 1. In the view of the lower critical stress level, wet electrode, containing much diffusible hydrogen content shows lower value than dried electrode. 2. Hardness value(Hv 5kg) in Heat Affected Zone of wet electrode is higher than that of dried electrode caused by hydrogen embrittlement. 3. In the case of wet electrode, root crack is initiated and propagated in Heat Affected Zone and then propagated to weld metal, but using of dried electrode, root crack is initiated in Heat Affected Zone and propagated to weld metal without propagating in HAZ. 4. For wet electrode, quasi-cleavage fracture mode is majorly observed on the fracture surface of HAZ and partially of weld metal due to hydrogen embrittlement.

• Magazine of the Korean Society of Agricultural Engineers
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• v.20 no.1
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• pp.4599-4613
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• 1978

This study was intended to investigate the effects of bituminous material content of soil-cement mixtures on their durability. For the purpose, unconfined compressive strength test, Freeze-thaw test, and wet-dry test were performed with three types of soil. Each type of soil was mixed with three levels of cement content and each soil-cement mixture was mixed with four levels of bituminous material content. For the unconfined compressive strength test, Freeze-thaw test and wet-dry test, 324, 108, and 108-specimens were prepared respectively. Unconfined compressive strength was measured at age of 7-days, 14-days and 28-days using 108-specimens in each age. The soil-cement loss rate due to freeze-thaw and wet-dry were calculated after 12 cycles of test using 108-specimens in each test. The results are summarized as follows : 1. Optimum moisture content was increased with increase of cement content, but maximum dry density was changed irregulary with increase of the cement content. 2. The unconfined compressive strength was increased with increase of cement content, bituminous material content and curing age. Cement is more effective factor than bituminous material on unconfined compressive strength of soil-cement Mixture. 3. It is estimated as the most economical cement content that the recommended cement content of A.S.T.M. because increasing rate of unconfined compressive strength at age of 28-days was low when cement content is above the recommanded cement content of A.S.T.M. among all types of soil. 4. Although a portion of cement content is substituted for bituminous material, the necessary unconfined compressive strength can be obtained. 5. The soil-cement loss was more influenced by wet-dry than Freeze-thaw 6. The bituminous material is more effective on the decrease of soil-cement loss than increase of unconfined compressive strength 7. The void ratio of soil-cement mixture was changet irregularly with increase of cement content, but that was decreased in proportion to the increase of bituminous material content. 8. The regression equation between the unconfined compressive strength and soil-cement loss rate were obtained as table 7.

• Corrosion Science and Technology
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• v.3 no.3
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• pp.98-101
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• 2004

The corrosion behavior of Al-Fe coatings was studied in the wet-seal atmosphere of molten carbonate fuel cells (MCFC). Fe-8Al, Fe-16Al, Fe-25Al, Fe-36Al, and Fe-70Al (in at.%) specimens were tested in Li/K carbonate at $650^{\circ}C$ by a single cell test and an immersion test. In general, the corrosion resistance of the Al-Fe coatings was enhanced due to the formation of a protective $LiAlO_2$ layer. However, when the Al-Fe coatings didn't have sufficient content of aluminum enough for maintaining the protective layer, the corrosion resistance of the Al-Fe coatings was severely degraded by the growth of non-protective scales like $LiAlO_2$. The test results revealed that the aluminum contents in the coatings should be higher than 25 at.% in order to form and maintain the protective $LiAlO_2$ layers.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.137-138
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• 2017

The Waterproofing and Anti corrosion materials applied to the water supply facility did not consider environment of water supply facility, thus defects occurred consistently on the site. In this study, it suggests safety adhesion test of wet surface and have a test for safety adhesion performance.

• Journal of the Korean Wood Science and Technology
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• v.1 no.2
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• pp.11-15
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• 1973

This study was carried out to utilize sweet potato, and jerusalem artichoke flour as an extender of urea formaldehyde resin for plywood manufacture. The results obtained are summarized as follows: 1) In dry and wet test of plywood, sweet potato flour extended in urea formaldehyde resin was shown better strength than those of wheat flour. 2) Sweet potato flour was shown good results up to 200 percent extension in the dry test, and there was not shown significant difference between 100 percent and 150 percent extension in the wet test. 3) In the case of 100 percent extension, potato flour was shown best dry shear strength(400 psi) and sweet potato flour was shown best wet shear strength (212 psi).

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1162-1167
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• 2004

From the early 1980's, the New Austrian Tunnelling Method (NATM) has been developed as a one of the standard tunneling method in Korea. Owing to the results of many researches, the practical problems of shotcrete has been improved for a last decade. However, the excess amount of rebound still remains one of the critical problems in shotcrete technology. In order to improve for this rebound problem, recently developed cement mineral accelerator has been successfully applied to several NATM tunnels in Korea. An experimental investigation was carried out in order to verify the rebound characteristics of wet-mix Steel Fiber Reinforced Shotcrete (SFRS) with powder types cement mineral accelerator. Mortar setting test, SEM analysis, bonding test under spring water condition and rebound test were conducted. From the result, wet-mix SFRS with cement mineral acelerator exhibited excellent bonding characteristics even spring water condition and less rebound ratio compared to the conventional liquid accelerator.