• Title/Summary/Keyword: Combined Deterioration

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Temperature History of the Wall Concrete Subjected to -10℃ depending on Heat Curing Method (-10℃ 조건에서의 보온양생방법 변화에 따른 벽체 콘크리트의 온도이력)

  • Han, Sang-Yoon;Son, Ho-Jung;Cheong, Sang-Hyun;Ahn, Sang-Ku;Han, Cheon-Goo;Han, Min-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.255-256
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    • 2011
  • This study investigates the effect of a curing condition on the temperature history and strength development of concrete under -10℃. Combination of various curing methods was applied, i.e. a conventional form was combined with compressed insulation, heat panel and heat cable. Results showed that the concrete cured by a single use of a conventional form resulted in serious deterioration of early strength development. However, other concretes cured by the proposed curing methods maintained the temperature of the concretes between 5 and 20℃, and thus resulted in no frost damage.

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An Experimental Study on Physical Properies of Concrete with Packaged Dry Combined Materials (건식혼합 포장 콘크리트의 물리적 특성에 관한 실험적 연구)

  • Han, Da-hee;Park, Hee-Gon;Lee, Young-Do;Jung, Sang-Jin
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.2 s.16
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    • pp.131-138
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    • 2005
  • Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new rapability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore, For solving the problems we apply to a packing method for using dried materials. That is to say that it is a kind of making into an instant. In this study. There is a purpose to present fundamental data, comparing and analyzing a phenomenon of aggregate's absorption following the rate of adding water, for using existing materials.

Development of combined waterproofing method of top-down double reinforced method using two-blade protruding waterproof sheet(Mock-Up Test) (양날개 돌출형 방수시트를 이용한 접합부 탑다운 2중 보강방식 복합방수공법의 개발 연구(Mock-Up Test))

  • Choi, Eun-Gyu;Song, Je-Young;Lee, Sun-Gyu;Park, Jong-Sun;Kim, Byoung-Il;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.05a
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    • pp.279-280
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    • 2018
  • The waterproofing material can be roughly divided into a coating material and a sheet waterproofing material. In the case of coating waterproofing materials, sheet waterproofing materials, which are easy to use in terms of workability and quality control, have been recently used because of their incomplete use of coating thickness, long curing time and poor blending due to in situ blending. However, in the case of the sheet waterproofing material, since the sheet overlapping portion is inevitably generated, various defects (breakage due to the behavior) are frequently observed. Therefore, it is imperative to establish fundamental measures to minimize this.

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A Fundamental Study on Method of Packaged Dry Combined Materials for Concrete using Powder Admixture - based on tests for hardened concrete (분말혼화제를 사용한 콘크리트 포장화에 관한 기초적 연구 - 굳은 콘크리트 시험 중심으로 -)

  • Han Da Hee;Son young Jun;Jung Kwang Sic;Park Hee Gon;Lee Young Do;Jung Sang Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.153-156
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    • 2004
  • Most concrete is recently made of an aggregate which is properly absorbed. and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore. For solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study. There is a purpose to present fundamental data. comparing and analyzing a phenomenon about aggregate's absorption following the rate of adding water. for using existing materials.

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An Fundamental Study on Method of Packaged Dry Combined Materials for Concrete (건조 재료를 사용한 콘크리트의 포장화에 관한 기초적 연구)

  • Han, Da-Hee;Park, Hee-Gon;Lim, Nam-Gi;Kim, Sung-Sik;Lee, Young-Do;Jung, Sang-Jin
    • Journal of the Korea Institute of Building Construction
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    • v.3 no.4
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    • pp.119-122
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    • 2003
  • Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate Therefore, For solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study, There is a purpose to present fundamental data, comparing and analyzing a phenomenon about aggregate's absorption following the rate of adding water, for using existing materials.

Experimental evaluation on the seismic performance of high strength thin-walled composite members accounting for sectional aspect ratio effect

  • Hsu, H.L.;Juang, J.L.;Luo, K.T.
    • Steel and Composite Structures
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    • v.9 no.4
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    • pp.367-380
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    • 2009
  • This study focuses on the experimental evaluation of the flexural-torsional performance of high strength thin-walled composite members. A series of tests on composite members with various sectional aspect ratios subjected to eccentric cyclic loads were conducted. Test results show that the composite member's torsional strength could be approximated using a series of linear segments and evaluated using the superposition of the component steel and reinforced concrete responses. It is also validated from the tests that the strength deterioration of members subjected to combined loads is closely related to the aspect ratios of the sections. An interaction expression between the bending and torsion for high strength thin-walled composite members is proposed for engineering practice references.

A Study on the Development of Crack Diagnosis Robot for Reinforced Concrete Structures Based on Image Processing (이미지 프로세싱 기반 철근콘크리트 구조물의 균열진단 로봇 개발에 관한 연구)

  • Kim, Han-Sol;Jang, Jong-Min;Kim, Yeung-Kwan;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.103-104
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    • 2022
  • Cracks may occur in reinforced concrete (RC) structures due to various physical and chemical factors, and the growth of cracks causes deterioration of the structure's performance. It is important to prevent the expansion of cracks through periodic diagnosis of cracks in structures. In order to enable free crack exploration even in a narrow space, a construction robot using a Mecanum wheel that can move up, down, left and right and rotate in place was designed. High-quality crack images were periodically collected through the camera, and the image fragments stored during the exploration were combined into a single photo after the exploration was completed. The robot detected cracks with a width of 0.2 mm or more on the concrete probe surface with an accuracy of about 90% or more.

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Effect of Dietary Vitamin A and E Peroxidative Deterioration of Heart in Adriamycin-Treated Rats (식이중의 Vitamin A와 E가 Adriamycin을 투여한 흰쥐의 심근손상의 원인인 과산화작용에 미치는 영향)

  • 정영아
    • Journal of Nutrition and Health
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    • v.25 no.5
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    • pp.379-388
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    • 1992
  • The present study was designed to evaluate the protective effects of dietary vitamin A or E. and of combination of vitamins A and E on peroxidative deterioration of heart in adriamycin-treated rats. Male Sprague-Dawley rats were assigned to 5 groups according to the dietary supplementation of vitamin A or E Except control rats a dose of 2mg ADR/kg of B. W was injected to these animals intraperitoneally on the same day every week. Adriamycin treatment significantly decreased the weight gain of experimental rats compared with that of control rats, But this decrement was not modified by dietary supplementation of vitamin A or E. Lipid peroxide values of plasma were elevated by ADR treatment. The combined use of ADR and dietary vitamin A or E significantly reduced these values, The interaction between vitamins A and E seemed to be present in the lipid peroxide value of plasma. Catalase and superoxide dismutase(SOD) activities in rat heart were decrased by ADR treatment but glutathione peroxidase(GSH-Px) activity was elevated. Dietary supplmen-tation of vitamin A or E enhanced the heart catalase and SOD activities. except only vitamin A-supplemented group. GSH-Px activity of rat heart tended to be decreased by dietary supple-mentation of vitamin A or E. With ADR treatment polyunsaturated fatty acids such as archido-nic acid(20:4) and docosahexaenoic acid(22:6) were decreased in rat heart. However dietary supplementation of vitamins A and E reduced this decrease. The retinol and tocopherol contents of rat plasma were decreased by ADR treatment. Dietary vitamin A or E influence vitamin A or E content of plasma. The interaction between dietary vitamins A and E was observed in vitamin A or E level of rat plasma.

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Improvement of Hygienic Quality and Long-term Storage of Dried Red Pepper by Gamma Irradiation (감마선 조사에 의한 건고추의 위생화와 장기 안전저장)

  • Byun, Myung-Woo;Yook, Hong-Sun;Kwon, Joong-Ho;Kim, Jung-Ok
    • Korean Journal of Food Science and Technology
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    • v.28 no.3
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    • pp.482-489
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    • 1996
  • Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

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Effect of Carcass Electrical Stimulation and Suspension Methods on Meat Quality Characteristics of Longissimus lumborum of Young Buffalo (Bubalus bubalis) Bulls

  • Jaspal, Muhammad Hayat;Ijaz, Muawuz;Akhtar, Muhammad Junaid;Nasir, Jamal;Ullah, Sana;Badar, Iftikhar Hussain;Yar, Muhammad Kashif;Ahmad, Arfan
    • Food Science of Animal Resources
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    • v.41 no.1
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    • pp.34-44
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    • 2021
  • Buffalo animals are slaughtered at their early age and carcasses are chilled rapidly which deteriorates its meat quality and decreases the consumer likeliness of buffalo meat. This study investigated the appropriate methods to prevent the quality deterioration of buffalo meat during chilling. Twenty four 18-mon-old buffalo bulls were slaughtered, electrically stimulated and suspended either by hip or achilles tendon. After 24 h postmortem, meat quality characteristics were recorded. Results showed that electrical stimulation (ES) led to rapid decline of carcass pH compared to non-ES method (p<0.05). Furthermore, electrically stimulated meat presented lower shear force accompanied with the higher CIE L⁎, a⁎, and b⁎ values (p<0.05). Suspension methods only affect the meat shear values and were lowered in hip suspended samples. It can be concluded that ES combined with hip suspension can be adopted to prevent the meat quality deterioration of young buffalo bulls during postmortem storage.