• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1049-1058
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• 2001

The performance and design analysis for a NWD cooling tower using a combined wet and dry type fill are numerically investigated and compared with the experimental results. The Stoecker's method is applied to the wet section and LMTD or NTU-Effectiveness method to the wet and dry sections. The efficiency ratio of the NWD cooling tower to a wet type crossflow cooling tower is 59.34%. The predicted result shows a good agreement with the experimental data within 1.4% error. Plume abatement is far better with a NWD cooling tower than a counterflow cooling tower. It costs less than a conventional wet/dry tower because the finned exchanger is eliminated. This method also leaves out complexity in structure and Intricacy in operation.

• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.55-61
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• 1994

Mn-Zn ferrite powder was obtained by wet method that was to be coprecipitated the metal ions of Fe2+, Mn2+ and Zn2+ with alkali solution. The target composition of the ferrite powder was 52 mol% Fe2O3, 24 mol% MnO, and 24 mol% ZnO, that was based on the region of high permeability. And the other ferrite powder was prepared by the dry method that was to be mixed the metal oxides as the above chemical composition. The wet method was compared with dry method for the powder properties and the electromagnetic characteristics of sintered cores. The synthesized powder by wet method was smaller particle size, narrower particle distribution, and higher purity than that of dry method. The initial permeability of sintered sample prepared by the wet method was 14000~28000, on the other side, 9000~15500 in case of the dry method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.2
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• pp.158-162
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• 2001

In this report, a new process for patterning of YBaCuO thin films, ICP(inductively coupled plasma) method, is described by comparing with existing wet etching method. Two 100㎛ wide and 2mm long YBaCuO striplines on LaAlO$_3$ substrates have been fabricated using two patterning techniques. And the properties were compared with the critical temperature and the SEM photography. Then, the critical temperatures of two samples were about 88 K, but the cross section of sample using ICP method was shaper than that using the wet etching method. ICP method can be used as a good etching technique process for patterning of YBaCuO superconductor.

• Journal of the Korean Ceramic Society
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• v.16 no.3
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• pp.155-163
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• 1979

This study was to explore the characteristics of 6 mole% CaO stabilized $ZrO_2$ prepared by wet chemical methods. The results of the experiments were as follows: 1. The powder calcined at 1000$^{\circ}$-110$0^{\circ}C$ was partly agglomerated. The morphology of agglomerate was spherical of 0.5-1$\mu{m}$ in size for Hot Petroleum Drying Method, chain-like of 1-2$\mu{m}$ for Freeze Drying Method, and irreqular of 2-3$\mu{m}$ for Coprecipitation Method. 2. Optimum calcining conditions for powder prepared by wet chemical methods were found: 110$0^{\circ}C$, 2h in air for Hot Petroleum Drying Method and Freeze Drying Method, and 100$0^{\circ}C$, 2h in air for Coprecipitation Method. 3. When specimen was calcined at 1000$^{\circ}$-110$0^{\circ}C$ in air for 2h and then sintered at 1$600^{\circ}C$ in air for 4h, the specimens prepared by wet chemical methods showed a high sintered density (94% of theoretical density) and a low open porosity (<0.8%); however, the sintered density of the specimen prepared by Oxide Wet Mixing Method was 90%. 4. The amount of cubic phase of sintered body prepared by wet chemical methods was observed to be higher than the one prepared by Oxide Wet Mixing Method. 5. It was found that Hot petroleum Drying Method, Freeze Drying Method and Coprecipitation Method were nearly the same in respect of the results of stabilization grade and sintered density of CaO-stabilized $ZrO_2$.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.59-63
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• 2008

Purpose: The purpose of this study is to understand a relation of water content measurement with two different method, water removal method and dry method. Methods: 72 hydrogel contact lens containing various water content (ranged from 47% to 58%) were measured by the gravimetric method at 20$^{\circ}C$and 21% of the humidity. We weighed the dried test specimen at room temperature for 30 min after cooling. Results: In dry blotting method, the water content was measured to 47.43${\pm}$8.48%. The water contents was measured to 48.15${\pm}$8.36% with wet blotting condition. It was found that wet blotting method showed the higher water content of about 7% than dry blotting method. In water content with two dry methods, each of results was measured by 47.89${\pm}$8.06% and 49.56${\pm}$7.06%. In case of microwave method, the water content was measured significantly higher water content of about 1.67% than vacuum oven method. However, no statistical difference was found (p>0.05). Conclusions: In water removal method (Dry blotting method and Wet blotting method) to weigh hydrated test specimen, wet blotting method showed significantly higher water content than dry blotting method. Also in case of dry methods (vacuum oven and microwave) to weigh dry test specimen, water content of microwave method showed higher water content than vacuum oven method, but it should be noted that microwave oven method must be used carefully to measure accurateness on the specimen position and wave power.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3280-3288
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• 2014

Alkoxyalcohols are used as solvents or preservatives in various consumer products such as wet wipes. The metabolites of alkoxyalcohols are known to be chronically toxic and carcinogenic to animals. Thus, an analytical method is needed to monitor alkoxyalcohols in wet wipes. The aim of this study was to develop a simultaneous analytical method for 14 alkoxyalcohols using headspace gas chromatography coupled with mass spectrometry to analyze the wet wipes. This method was developed by comparing with various headspace extraction parameters. The linear calibration curves were obtained for the method ($r^2$ > 0.995). The limit of detection of alkoxyalcohols ranged from 2 to $200ng\;mL^{-1}$. The precision of the determinative method was less than 18.20% coefficient of variation both intra and inter days. The accuracy of the method ranged from 82.86% to 119.83%. (2-Methoxymethylethoxy)propanol, 2-phenoxyethanol, and 1-phenoxy-2-propanol were mainly detected in wet wipes.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.253-258
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• 1998

To verify the suitability of microwave digestion method for analyzing macro nutrients and metals. K, Ca, Mg, Cu, Zn, and Mn contents in plant and composts were investigated comparing with conventional wet digestion method. Because it takes short time to digest metal samples by using microwave method compared with conventional wet digestion method. Digestion time for metal samples was four to six hours long for wet digestion, while one hour long for microwave digestion. Determinant coefficients of Cu, Mn, Zn, Ca, K, and Mg contents between two analyzing methods were 0.99, 0.99, 0.94. 0.97, 0.98, and 0.91, respectively. In the case of Ca and K, microwave digestion method analyzed their contents relatively low compared with wet digestion method. Meanwhile, microwave digestion method analyzed the contents for Cu, Ma, and Zn relatively high compared with wet digestion method. This study results in that microwave digestion method could be an alternative to replacing conventional wet digestion method.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1331-1334
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• 2004

Wet/Dry phenomena typically incorporate a number of complex flow mechanism. These include a momentum transfer and turbulent mixing caused by the delivery of water. However currently available one dimensional schemes applicable to wet/dry process cannot effectively simulate such process. Two dimensional finite element model, SU/PG, is used to simulate complex flow in this study. The Wetted Area Method in SU/PG allows elements to transition gradually between wet and dry states. The model is applicable to a straight river reach with irregular bathymetry. Wet/dry calculation using the wetted area method can simulate simple numerical test. The computed results of velocity vectors and water depth agree with those of observed. The methodology Presented in this study will contributed to two-dimensional wet/dry analysis in a river in this country.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.624-628
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• 2008

Two-dimensional flow analysis is a way to provide good estimates for complex flow features in flow around islands and obstructions, flow at confluence and flow in braided channel. One of difficult problems to develop a two-dimensional hydraulic model is to analyze dry and wet area in river channel. Dry/wet problem can be encountered in river and coastal engineering problems, such as flood propagation, dam break analysis, tidal processes and so on. The objective of this study is to develop an accurate and robust two-dimensional finite element method with dry/wet technique in complex natural rivers. The dry/wet technique with Deforming Grid Method was developed in this study. The Deforming Grid Method was used to construct new mesh by eliminating of dry nodes and elements. The eliminated nodes and elements were decided by considering of the rising/descending velocity of water surface elevation. Several numerical simulations were carried out to examine the performance of the Deforming Grid Method for the purpose of validation and verification of the model in rectangular and trapezoidal channel with partly dry side. The application results of the model were displayed reasonable flow distribution.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.54-64
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• 2019

Wet and dry aging methods were applied to improve the quality of three different beef cuts (butt, rump, and sirloin) from Hanwoo cows (quality grade 2, approximately 50-mon-old). After 28 d of wet aging (vacuum packaged; temperature, $2{\pm}1^{\circ}C$) and dry aging (air velocity, 2-7 m/s; temperature, $1{\pm}1^{\circ}C$; humidity, $85{\pm}10%$), proximate composition, cooking loss, water holding capacity, shear force, color, nucleotides content, and sensory properties were compared with a non-aged control (2 d postmortem). Both wet and dry aging significantly increased the water holding capacity of the butt cuts. Dry aging in all beef cuts induced lower cooking loss than that in wet-aged cuts. Shear force of all beef cuts was decreased after both wet and dry aging and CIE $L^*$, $a^*$, and $b^*$ color values in butt and sirloin cuts were higher in both wet and dry aging (p<0.05) groups than those in the non-aged control. Regardless of the aging method used, inosine-5'-monophosphate content among beef cuts was the same. The sensory panel scored significantly higher values in tenderness, flavor, and overall acceptability for dry-aged beef regardless of the beef cuts tested compared to non- and wet-aged cuts. In addition, dry-aged beef resulted in similar overall acceptability among the different beef cuts, whereas that in wet-aged meat was significantly different by different beef cuts. In conclusion, both wet and dry aging improved the quality of different beef cuts; however, dry aging was more suitable for improving the quality of less preferred beef cuts.