• The Journal of Korean Academy of Prosthodontics
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• v.27 no.1
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• pp.193-211
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• 1989

The purpose of this study was to investigate the effect of secondary heat treatment on dimensional changes of acrylic resin partial denture base. For this study, 6 specimens were made: 2 groups of 2 specimens, each was treated with $125^{\circ}C$ dry heat and glycerine heat for 3 minutes, and the others were prepared for control group. The change of the internal diameter of specimens were measured after 3 hrs, 1 day, 1 week, 2 weeks, 4 weeks by three-dimensional space analyzer. The results were as follows : 1. All of the acrylic resin denture bases showed tissue ward thermal contraction. 2. Thermal contraction of the mesial area reinforced with metal framework was lesser than that of the distal area without metal framework. 3. Thermal contraction of the lingual flange reinforced with metal framework occured more slowly than that of the buccal flange without the metal framework. 4. The thermal contraction of dry heat treated acrylic resin base, compared to glycerine heat group, was moderately greater and occurred acutely.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.225-231
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• 2022

In this study, the conditions of dry heat treatment (21 days at 65℃, 16 days at 70℃, 10 days at 75℃, and 7 days at 80℃) were investigated to inactivate Bacillus cereus ATCC 12480, Listeria monocytogenes ATCC SSA81, Staphylococcus aureus ATCC 6538, Escherichia coli O157:H7 ATCC 43894, and Salmonella Typhimurium ATCC 14028 on alfalfa seeds, without affecting the rate of germination of seeds. Alfalfa seeds were inoculated at levels of 6-7 log CFU/g and treated with dry heat at 65℃, 70℃, 75℃, and 80℃; thereafter, the rate of seed germination was determined. The rate of germination was set at 70%, according to the market standards. The bacteria were inactivated when B. cereus was treated with dry heat for 21 days at 65℃, 18 days at 70℃, 14 days at 75℃, and 4 days at 80℃; L. monocytogenes was treated for 21 days at 65℃, 18 days at 70℃, 12 days at 75℃, and 7 days at 80℃; S. aureus was treated for 18 days at 65℃, 18 days at 70℃, 11 days at 75℃, and 4 days at 80℃; E. coli O157:H7 was treated for 21 days at 65℃, 18 days at 70℃, 12 days at 75℃, and 6 days at 80℃; and Sal. Typhimurium was treated for 24 days at 65℃, 22 days at 70℃, 14 days at 75℃, and 7 days at 80℃. For all bacteria, the D-value (R² = 0.5656-0.7957) significantly decreased when the temperature increased from 65℃ to 80℃ (P<0.05). Since dry heat treatment of alfalfa seeds at 80℃ for 7 days affects their germination rate, dry heat treatment at 75℃ for 14 days is the most effective way to ensure their safety. This study suggests a potential method of bacterial inactivation using dry heat treatment to increase the microbiological safety of sprouts.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.596-602
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• 2008

Ovotransferrin (OTf) was phosphorylated by dry-heating in the presence of pyrophosphate at pH 4.0 and $85^{\circ}C$ for 1 and 5 d, and the functional properties of phosphorylated OTf (PP-OTf) were investigated. The phosphorus content of OTf increased to 0.91% as a result of phosphorylation and the electrophoretic mobility of PP-OTf also increased. Although the solubility of dry-heated OTf slightly decreased, the decrease was reduced by phosphorylation. The stability against heat-induced insolubilization of OTf was somewhat improved by phosphorylation, but more than 70% of PP-OTf was insolubilized when it was heated at $70^{\circ}C$ for 10 min at pH 7.0. However, heat-induced insolubilization of PP-OTf was reduced when it was heated in the presence of phosphorylated ovalbumin. This may explain the excellent stability of phosphorylated egg white protein against heat-induced insolubilization which was reported previously. The emulsifying property of OTf was also somewhat improved by phosphorylation. The calcium phosphate-solubilizing ability of PP-OTf was enhanced. Although the degree of phosphorylation of OTf by dry-heating in the presence of pyrophosphate was similar to that of ovalbumin, the improvement of properties of PP-OTf was considerably different from those of phosphorylated ovalbumin.

• Journal of computational fluids engineering
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• v.21 no.2
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• pp.54-61
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• 2016

When spent fuel assemblies from the reactor of nuclear power plants(NPPs) are transported, the assemblies are exposed to short-term operations that can affect the peak cladding temperature of spent fuel assemblies. Therefore, it needs to perform the analysis of heat transfer on spent fuel dry cask during the operation. For 3 dimensional computational fluid dynamnics(CFD) simulation, it is proposed that the short-term operation is divided into three processes: Wet, dry, and vacuum drying condition. The three processes have different heat transfer mode and medium. Metal transportation cask, which is Korea Radioactive Waste Agency(KORAD)'s developing cask, is evaluated by the methods proposed in this work. During working hours, the boiling at wet process does not occur in the cask and the peak cladding temperatures of all processes remain below $400^{\circ}C$. The maximum peak cladding temperature is $173.8^{\circ}C$ at vacuum drying process and the temperature rise of dry, and vacuum drying process occurs steeply.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.349-356
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• 2006

The purpose of this study was to compare the thermophysiological responses and subjective sensations of clothing materials with different water transfer property investigated in exercising and resting subjects at an ambient temperature of $20^{\circ}C$ and a relative humidity of 40%. Two kinds of clothing ensemble were tested: 100% cotton with highly water-absorbent but slowly dry properties(C) and 100% polyester with quickly water-absorbent and dry properties by four capillary channels(QADP). Seven apparently healthy male participants each undertook two series of experiments comprised 10-min of rest, 20-min of exercise with 70% of $VO_{2max}$ on a treadmill and 20-min of recovery. Mean skin temperature was significantly lower in QADP than in C during exercise and recovery. Clothing microclimate temperature was significantly lower in QADP during exercise and clothing surface temperature was also lower in QADP especially during recovery. Also, clothing surface humidity was significantly higher in QADP after the later half of exercise. The concentration of blood lactic acid tended to decrease to a lower level at recovery 3 minutes when wearing QADP rather than C clothing ensemble. Metabolic energy was marginally significantly less during the second half of exercise in QADP. Body mass loss tended to be greater in C than in QADP. The participants had better scores in thermal sensation, comfortable sensation and wetness in QADP during exercise and recovery. These results show that functional materials with quickly water-absorbent and dry properties can alleviate heat strain and induce more comfortable clothing microclimates and subjective sensations in the exercise-induced hyperthermia.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.41-46
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• 2003

In this paper, two different methods are developed to be used for the design of noncontact dry gas seal which is used to prevent gas leakage of high speed rotating shaft-housing machineries. First method is using FEA to compute the deformation of seal face and the other is using Influence Coefficient Method in order to save computation of FEA. In both cases, heat load and mechanical loads are applied such as heat generation, bulk temperature and nodal force, bulk pressure, centrifugal force, respectively. ICM method is verified correct and effective and both methods give reliable and useful deformation results for the design of mechanical seals.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.251-257
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• 2000

A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaeger's formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along line of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.2
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• pp.331-337
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• 2001

A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaegers formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along ling of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

• Fashion & Textile Research Journal
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• v.2 no.3
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• pp.220-226
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• 2000

This study was to determine the characteristics of vapor-permeable waterproof finished fabric by the coating method. 4 different kinds of coating fabrics (A : wet, porous, polyurethane, B : dry, no porous, polyurethane, C : shape memory polyurethane and D : dry, porous polyurethane) were used, which were developed recently With this sample, moisture transport rate ($40^{\circ}C$, 45%RH & $40^{\circ}C$, 95%RH), changes of coating side's shape by washing times, water repellency rate, contracted length, qmax, heat conductivity, heat keeping rate, heat keeping rate with cotton, heat keeping rate on humidity temperature and humidity within clothing etc. were checked. And it was done in a climate chamber under $20{\pm}2^{\circ}C$, $65{\pm}5%RH$. The results of this study were as follow; In the moisture vapor transmission of sample B and C increased on high temperature and high humidity while sample A and D decreased, on this condition. Qmax rate had high relation with ground fabric's surface properties and the order was A>C>D>B. Heat conductivity had high relation with thickness and surface properties. Heat keeping rates on sweat condition showed around half percents of heat keeping rates on normal condition, but had no relation with moisture vapor transport rate. Changes of the fabric's properties by washing times were different in accordance with the construction of fabrics and the coating resin. Sample C had tow heat keeping rate on the high temperature and humidity and high heat keeping rate on the low temperature and humidity Moisture transport rate of vapor-permeable waterproof finished fabrics had high relation with the properties of ground fabrics on low humidity condition, but on the high humidity condition, it was highly related with the properties of coating resin.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.173-178
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• 2005

The tile construction methods for existing have been used materials within limit which adhesion by wet method in masonry wall and concrete structure. These existing adhesive tech can caused many problems in construction of large and reform tile, after that it can be happened loose scale, peel off, falling off tile by heat and vibration or impact. In according to, this study is to test tile for bond stability, adhesive property by impact, vibration. low property by heat and then, we have the results as below; (1) The tile adhesive stability can be effected as adhesive area between bond agent and tile, adhesive area can more wide and press enough to ensure property. (2) Existing adhesive strength and standard relative tile construction is limited to adjust performance tile on the concrete and masonry wall. In summary, It is necessary to establish standard of performance and test method to ensure tile adhesive salability in dry wall.