• Korean Journal of Construction Engineering and Management
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• v.5 no.6 s.22
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• pp.212-217
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• 2004

Carbon fiber reinforced plastic(CFRP) plate Is one of the alterative materials for soengthening of reinforced and prestressed connote members due to excellent strength and light weight In this paper, the behavior of beams strengthened with CFRP plate and CFS(Carbon fiber sheet) is observed and analyzed from the test results. Especially specimens with thick plate is tested when large moment and large shear lone appear in same position. The main failure mode is a peeling-off of the CFRP plate near the loading points due to flexural-shear crack, Because of this failure mode, failure load is not linearly proportional to the thickness of CFRP plates. When beam is wrapped with CFS around oかy loading point it does not influence on the failure loads. Depending on the loading pattern, it is necessary to consider different design criteria for reinforced concrete members with external reinforcement. When line moment and large shear force appear in same location, maximum thickness may limit to 0.6mm and ratio between moment of strengthened beam and moment of unstrengthened beam is proposed 1.5-2.0. In order to use the plate of thicker than 6mm, CFS may be extended to the location which moment of strengthened beam is 1.5 times than moment of unstrengthened beam.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.219-226
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• 1981

To enable off-season peach canning, peaches were halved and processed into solid packs. Following variables were compared in relation to storage stability of solid packs. First as pretreatment-dipping in citric and ascorbic solution after lye peeling; second as pasturization in pouch and hot fill process; third as packaging method-2 ply(PET/PE) and 3 ply(PET/Al/PE) plastic film pouch and metal container; fourth as storage condition $-20^{\circ}C\;and\;-5^{\circ}C$. After 25 weeks storage test, all peaches in different packs were processed into canned peaches just like commercial products, and then quality was organoleptically evaluated from the viewpoint of processing and storage variable of solid packs. The results are follows; 1. Ascorbic acid dipping in 3 ply pouch and citric acid dipping in 2 ply pouch had better quality retention effect than any other pretreatments in respective packing. 2. Pasteurization method gave great effect on the color and texture of the solid pack during storage, but not on the quality of the final canned peach. 3. Can and 3 ply packing were better than 2 ply pouch in storage of solid pack and quality of final canned peach. 4. The $5^{\circ}C$ storage gave better quality than $20^{\circ}C$.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.589-592
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• 2008

This study was conducted to assess the durability of Chloride-inhibiting Low-Heat Cement while being subjected to freezing-thawing during winter seasons. Although durability varies slightly depending on the conditions of the jobsite, frost damage to concrete resulting from repeated freezing and thawing over the course of seasonal changes is the leading cause behind lowered concrete durability. in addition, concrete that has been subjected to freezing and thawing during the winter season develops a significant amount of expansive force at the core and begins to exhibit signs of damage, such as cracking, peeling, and detachment from the aggregate. Therefore, this study fabricated test specimens using a Chloride-inhibiting Low-Heat Cement(CLC) and the widely used blast furnace slag cement(BFS) and Ordinary Portland Cement(OPC) with water-to-cement ratios of 35%, 40% and 45%, respectively, to assess the durability index of the CLC as per resistance to freezing-thawing. The specimens were then tested using the KS F 2456 method (Testing method for resistance of concrete to rapid freezing and thawing) to measure the dynamic modulus of elasticity. The dynamic modulus of elasticity measurements were then used to derive the durability indices. By comparing the durability indices, it was confirmed that CLC, BFS, and OPC all had superior durability.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.127-134
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• 2009

This study investigated their properties of spalling resistance and residual compressive strength after fire test corresponding to various ISO, RABT heating curves, and contents of hybrid organic fiber of high strength concrete. The results were summarized as following. As fundamental characters of concrete with hybrid organic fiber, the flowability was directly declined as the increase of fiber contents, and air contents were decreased or increased a little bit, but there was not big difference. The compressive strength was gradually declined sluggishly at 28 days. As properties of fire resistance, in case of RABT heating curves, compare with ISO heating curves a spalling aspect showed till range that has much contents of hybrid organic fiber, but they are mostly peeling spalling, which means spalling aspect didn't happen to inside. In conclusion, in case of W/B 25% high strength concrete, the spalling was prevented over 0.04% of contents of fiber at ISO heating curve and over 0.10% of contents of fiber at the RABT heating curve. In case of spalling was prevented, mass reduction rate according to the change of heating temperature curves showed around 7% at ISO heating curves and around 9% at RABT heating curves. The residual compressive strength rate corresponding to the change of heating temperature curves showed 50%~60% at ISO heating temperature curves and 30%~35% at RABT heating temperature curves in case of spalling was prevented.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.98-108
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• 1974

Fourteen varieties of Korean chestnut were subjected to the test of adaptability for processing and the possibilities of colored products development. The fruit size of Korean chestnut ranged $11{\sim}18g$ and these small fruits could not be expected to be utilized for the processing of Marron glaces which requires larger size as $25{\sim}30g$. As the storge period is extended the discoloration tendency of chestnut flesh was increasingly developed, however, the fresh chestnut has shown layer-separating phenomenon and ragged surface of fruit which delivers disagreeable appearance to the finished product. The principal factors of discoloration occurred during processing were the behavior of tannin and darkening rate shown on flesh differed each other among varieties; the Chukpa and Yuma variety have exhibited the most serious discoloration and the Taab-b variety, the lightest. Taab-b variety in this connection could be expected to be available for Kanroni processing. For the industrialization of chestnut processing the flame-scorched peeling method is advisable. The capacity of this method is proportional to the square of scorching radius and highly flexible in controlling its performance. As for the processing of colored product, the sugar dehydration and coating and the sugar penetration method demand further study in basical views; however, the canned product of chestnut-redbean has shown the possibility of being utilized as a substitute for or paralleled use with the sugar-syruped canned product which so far has been considered as the only item of export to Japan.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.412-420
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• 2001

This study was conducted to identify the optimum cooking method and the ideal composition of Wax gourd Jung Kwa for the purpose of wide distribution. Wax gourd Jung Kwa was made by peeling off the wax gourd, digging out the stuff, slicing, soaking the pieces in ash water, and boiling slightly, then boiling down in honey, grain syrup. sugar, etc. As a result of sensory evaluation, the best color of Jung Kwa was observed in the recipe of pretreated wax gourd 300g, water 1 litre and grain syrup 495$m\ell$; for the flavor, hardness and chewiness, Pretreated wax gourd 300g, water 1 litre, corn syrup 475$m\ell$ and sugar 70g; for the adhesiveness, pretreated wax gourd 300g, water 1 litre and corn syrup 515$m\ell$; for the sweetness, pretreated wax gourd 300g, water 600$m\ell$ and sugar 90g and honey 120g. Overall Qualify was the highest in the recipe of pretreated wax gourd 300g, water 1 litre, com syrup 475$m\ell$ and sugar 70g, of which the sweetness was 74%. There were significant differences in all items (P＜0.05). For mechanical characteristics, the maximum cutting force was the highest in the samples with the recipe of pretreated wax gourd 300g, water 1 litre, corn syrup 475$m\ell$ and sugar 70g, and there were significant differences among all items (P<0.05). The highest moisture content, 45.54%, was observed in the recipe of pretreated wax gourd 300g. water 1 litre and corn syrup 475$m\ell$. There were significant differences among all items (P＜0.05). The L value(lightness) was the highest in the recipe of pretreated wax gourd 300g, water 1 litre, corn syrup 475 $m\ell$ and sugar 50g. The a value(redness) was the highest in the case of pretreated wax gourd 300g, water 1 litre, com syrup 475$m\ell$ and sugar 70g, which was almost red; and the b value(yellowness), wax gourd 300g, water 1 litre and corn syrup 475g, which gave almost Yellow color. Taking consideration of the above results, the most desirable recipe for wax gourd Jung Kwa was to mix the 300g of pretreated wax gourd with 20g of ash powder, boil them slightly for 2 min, soak them in cold water for 1 hour, and boil them down with 475$m\ell$ of com syrup, 70g of sugar, and 1 litre of water for 5 hours, resulting in the sweetness of 74%. The samples with above recipe were the best in flavor, chewiness and hardness in sensory evaluation, and showed the highest maximum cutting force and nearest red color in the mechanical test.