• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.261-264
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• 2002

Interfacial evaluation, damage sensing and cure monitoring of single carbon fiber/thermosetting composite with different curing processes was investigated using electro-micromechanical test. After curing, residual stress was monitored by measurement of electrical resistance (ER) and then it was compared to correlate with various curing processes. In thermal curing, curing shrinkage appeared significantly by matrix shrinkage and residual stress due to the difference in thermal expansion coefficient (TEC). The change in electrical resistance (ΔR) on thermal curing was higher than that on ultraviolet (UV) curing. For thermal curing, apparent modulus was the highest and reaching time until same strain was faster. So far thermal curing shows strong durability on the IFSS after boiling test.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.1
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• pp.25-41
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• 1990

The purpose of this study was to evaluate and compare the dimensional changes of relined dentures with a light-curing resin, a heat-curing resin, and a direct, hard reline resin. And also to measure the transverse strength, impact strength, surface hardness of the three resins used in relining. The surface textures of three resins also of evaluated by using scanning electron microscope. Through analyses on the data from this study, the following conclusions were obtained. 1. Impact strength of heat-curing resin was highest, and direct, hard reline resin higher, light-curing resin lowest. 2. Transverse strength of heat-curing resin was highest, and direct, hard reline resin and light-curing resin was lower and not signiicantly different. 3. Surface hardness of light-curing resin was lighest, heat-curing resin higher, and direct, hard reline resin was lowest. 4. After storage of the relined dentures for 1 day and 1 week in water at room temperature, linear shrinkage of distance between the reference points in the maxillary base relined with direct, hard reline resin was lowest, and those relined with light-curing resin and heat-curing resin were lower and were not significantly different. 5. After storage for 4 weeks in orator at room tempeature, linear shrinkage of distance between ridge crests of dentures relined with heat-curing resin was highest and that of distance between denture borders was not significantly different. 6. The dimensional changes of relined dentures during storage in water was not significant except those of distance between denture borders relined with light-curing resin at 1 day and 1 week storage in water. 7. At low magnification (x40) of SEM examination, the surface textures of three resins were similar except light-curing resin which had some defects. At high magnification (x200), the surface textures of hard, direct reline resin were smooth with little defects, but those of heat-curing resin and light-curing resin w ere irregular.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.11-20
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• 2013

PURPOSES : This study is to suggest time to spray curing compound, the amount of curing compound, and the number of times to spray curing compound based on indoor tests. METHODS : Based on the literature review, two methods are used in this study, One is test for water retention of concrete curing material and the other is test for abrasion resistance of concrete surfaces by the rotating-cutter method. Through those methods, curing compound was evaluated. RESULTS : The result of the laboratory experiment for time to spray curing compound indicates that 30 minutes after placing concrete is optimal. For the amount of curing compound, $0.5{\ell}/m^2$ is the minimum quantity for both concretes. Through test of the number of times to spray curing compound, method to spray the whole amount of curing compound in twice is more efficient than it to spray the whole amount at a time. Also, method of separately 30-50 minutes spray is better than method of separately 10-30 minutes spray. CONCLUSIONS : From the testing results, it can be proposed that optimum time to curing compound is $30{\pm}15$ minutes, $0.5{\ell}/m^2$ is efficient for spraying the whole amount of curing compound at a time, and $0.4{\ell}/m^2$ is the best for spraying the whole amount of curing compound in twice, which sprays it in 20 minutes after 30 minutes from placing concrete.

• Journal of Technologic Dentistry
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• v.9 no.1
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• pp.67-72
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• 1987

This experimental study presented the study on the dimensional changes of occuring for the denture curing methods. The method is as follows: 1. The master die was made of wax. 2. The Silicon Rubber Mold was made into the same 80 casts. 3. The 80 Wax Plate were made of using the Base Plate Wax. 4. Flasking, Wax-wash, & Resin-packing were performed by the general procedures. 5. The curing method is performed through the four curing methods. (A, B, C, D). Table 2 shows the dimensional change after a day. Table 3 shows the dimensional change after soaking for 30 days in water of the degree of 36 Centigrade. As a result, the A curing method is the most denture curing.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.114-121
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• 1996

This study presented a simple test method of early decision on the quality of concrete by the way of refrigeration curing. It is a method of early decision for the quality of hardened concrete, after 28days, through the using refrigeration curing, at -18$\pm$$3^{\cire}C$ for five hours. I could find that there were fixed connections between the solidities after 28days and 48days, by the test of compression on the Re-Mi-Con through the test of standard curing and refergeration curing. (F = 1.02X + 13, $r^2$ = 0.964, S = 10.6kg/$\textrm{cm}^2$) I except that we can reduce the mistakes of construction work by forecasting the quality through the refrigeration curing.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.751-756
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• 2003

This Paper concerns the compressive strength development tendencies of concrete according to their Ages and curing conditions. The test results are on follows; (1) The compressive strength development of concrete appears larger according to the curing conditions under water curing, condition structural curing and field curing conditions. (2) The compressive strength development rate of concrete after 28 days' curing becomes smaller, but the case of lower strength of concrete not.

• Journal of Technologic Dentistry
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• v.39 no.1
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• pp.25-33
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• 2017

Purpose: The aim of this study was to evaluate accuracy of glass fiber mesh complete denture of before and after curing. Methods: Edentulous model was selected as the master model. Ten study models were made by Type IV stone. Wax complete dentures were produced by the denture base and artificial teeth. CD and GD groups were measured six measurement distance before curing. The wax complete denture was investment after measurement is completed. Using a heat polymerization resin was injected resin. After injecting the resin it was curing. A complete denture was re-measured after curing. The measured data was verified by paired t-test. Results: Overall CD group was larger the value of the measured length. In the CD group, A-D point was larger. The smallest point was the B-D point. However, there was no statistically significant difference only C-D point(p>0.05). In the GD group, A-B point was larger. but B-D point was the smallest. A-D and B-C statistically points showed significant differences(p<0.05). Conclusion: Glass fiber mesh resin complete denture can be clinically applied to the edentulous patient.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.827-831
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• 1995

This study was designed to etermine the changes in the degree of conversion for composite resins after heat curing following the methods proposed by Lee & Park(1995). 8-mm diameter hole was made in 1mm teflon plate and one of three types of composites (Charisma, Brilllant, Z100) was placed and light cured for 60seconds. The samples were devided into 3 groups according to the placing composites. After light curing, the samples were separated from the moulds. Using this method, 10 samples were prepared in each group; 5 samples from each group were heat cured according to the methods proposed by manutfactures, These samples were then thinned to 50-$70{\mu}m$ and analysed with a Fourier Transform Infrared Spectrometer. Standard baseline technique was used to calculate the degree of conversion. When the samples were light cured, the degrees of conversion in each groups were 47.1 % (charisma), 53.3% (Z100), and 70.1 % (Brilliant). The degree of conversion after heat curing were; 60.1 % (Charisma), 71.1 % (Z100), and 73.3 % (Brillant). Once the samples were heat cured, there were significant increases in degree of conversion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.79-82
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• 2000

Tuberous root of yacon (Polymnia sonchifolia Poeppig ＆ Endlicher) has not starch, and its brix degree changes during the curing. Therefore its chemical composition changes were investigated according to different curing conditions. Tuberous root contained 87.1% moisture at harvesting, that was decreased to 84.1-86.0% at 30 days after curing in different curing conditions. Brix degree was increased from 5.7 to 14.2-15.8% at 30 days after curing in comparison to at harvesting. Free sugars were detected from tuberous root in yacon by HPLC; that were fructose, glucose and sucrose. Fructose contents were increased from 0.09 to 1.04-1.79% during 30 days in five curing conditions. Glucose contents were shown to increase from 0.03 to 1.04-1.37 %. Sucrose contents were shown to increase from 0.04 to 0.13-0.43%. Tuberous root contained fructose, glucose and sucrose in order of amount that were highest in single-polyethylene film covered green house. Sucrose was little as comparison with fructose and glucose. Fructose and glucose were increased to 16.7 and 40.7 times, respectively, but sucrose was increased little about 6.8 times.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.141-142
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• 2019

In this study, we conducted a comparative analysis of the effects of retention time and resuscitation method on the degree of resuscitation after reapplying mortar with much FA replacement. Results After applying NaOH to the top surface of 60 % FA-substituted mortar, the degree of resuscitation at $40^{\circ}C$ was high enough to increase the overall curing time, but there was no significant difference. However, with regard to the curing method, middle curing showed the greatest manifestation, followed by wrapping and underwater curing, but there was no significant difference. The resuscitation level on the 28th of the lumber was found to be revived to about 70~80 % at around 30 % without resuscitation.