• Title/Summary/Keyword: Accelerated environment

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Development Status of Korea Accelerated Loading and Environment Simulator (KALES) (한국형 포장가속시험시설의 개발현황)

  • Yang, Seong-Cheol;Yu, Tae-Seok;Eom, Ju-Yong
    • International Journal of Highway Engineering
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    • v.2 no.2
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    • pp.139-148
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    • 2000
  • Currently existing Accelerated Pavement Testing (APT) systems developed in several countries have been employed mainly to test the performance of asphalt pavement. Meanwhile, the length of concrete pavement is similar to that of asphalt pavement in expressways of Korea. and is expected to increase due to its durability and compatibility to our weather condition. To meet the society's demand of having our own APT system which can examine the long-term performance of concrete pavement, a contract study to develop Korea Accelerated Loading and Environment Simulator (KALES) for concrete pavement has been performed for 3 years from 1997 through 1999. Through the project, a detailed design was Peformed for the KALES system in which the entire structure of KALES, loading mechanism, wandering mechanism, suspension system, driving system were proposed. Also in advance to design a full-scale KALES system, a sample scale model was manufactured and tested for operating motion and force distribution. It is evident that the proposed prototype KALES system will provide higher degree of traffic simulation and durable operation, based on the satisfactory fatigue analysis.

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Corrosion Resistance of Cr-Bearing Rebar to Macrocell Corrosion Environment Induced by Localized Carbonation

  • Tae, Sung-Ho
    • International Journal of Concrete Structures and Materials
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    • v.18 no.1E
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    • pp.17-22
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    • 2006
  • Artificial cracks were made in the cover concrete of specimens embedding ten types of steel rebars of different Cr contents. The research aims for developing Cr-bearing steel rebars resistant to macrocell corrosion environments induced by cracking in cover concrete. The cracks were subjected to intensive penetration of carbon dioxide (carbonation specimens) to form macrocells. The carbonation specimens were then treated with accelerated corrosion curing, during which current macrocell corrosion density was measured. The corrosion area and loss from corrosion were also measured at the end of 105 cycles of this accelerated curing. The results of the study showed that Cr-bearing steel with Cr content of 5% or more suppressed corrosion in a macrocell corrosion environment induced by the differences in the pH values due to carbonation of cracked parts. Cr-bearing steels with Cr content of 7% or more are proven to possess excellent corrosion resistance.

Electro Chemical Protection Property for Reinforced Geo-Polymer Specimen Under Ocean Environment and Accelerated Test (철근보강 지오폴리머 콘크리트 시험체에 전기화학적 방식기법 적용과 방식성능 분석)

  • Park, Dong-Cheon;Cho, Gyu-hwan
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.178-179
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    • 2014
  • Corrosion is very serious problem in RC structure under ocean environment. There is no enough experiment information using the reinforced geo polymer concrete applied by electo chemical protection system. Three condition, such as tidal zone, submerged zone and crack were simulated to geo polymer specimen. Corrosion rate and natural electrode potential were measured through accelerated test. Anti corrosion property of geo polymer was better than OPC regardless of specimen condition and applied time.

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A Comparative Study on the Analytical Methods of Polycyclic Aromatic Hydrocarbons in the Atmosphere (대기 중 다환방향조탄화수소류의 분석 방법간 비교연구)

  • 박찬구;김민영;정동균;모세영
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.6
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    • pp.595-606
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    • 2000
  • In order to compare analytical conditions for measuring PAHs(polycyclic aromatic hydrocarbons) in ambient air, a series of experiment were conducted using three different types of extraction methods that include:(1) accelerated solvent extraction (ASE), (2) soxhlet, and (3) sonification methods. Efficiency and relevant analytixal parameters for each of these methods were examined on five different types of solvents that include:(1) 10% diethyl ether in n-hexane(v/v), (2) dichloromethane, (3)cyclohexane.(4) toluene, and (5) Benzene: ethanol (4:1). Comparison of extraction efficiency for various combinations between methods and solvents was made through an application of both internal and external standard calibration techniques. The extraction efficiency tests, when checked using both internal and external standards, allowed us to derive meaningful comparison among different techniques and among solvents.

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Degradation and hole formation of the Te-based thin films (Te을 기본으로 한 박막에서의 열화와 미세구멍형성에 관한 연구)

  • Lee, Hyun-Young;Park, Tae-Sung;Um, Jeong-Ho;Lee, Young-Jong;Chung, Hong-Bay
    • Proceedings of the KIEE Conference
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    • 1987.11a
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    • pp.207-209
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    • 1987
  • This paper reports the effect of additive elements such as Bi, Sb on degradation and hole formation of the Te-Se thin films. Changes in light transmission were used to monitor the degradation rate of thin Te films in an accelerated temperature-humidity environment. In thin accelerated temperature-humidity environment, $(Te_{86}Se_{14})_{70}Bi_{30}$ thin film was stable and $(Te_{86}Se_{14})_{50}Sb_{50}$ thin film was unstable in comparison with the other films that used in this experiment. The hole formation was carried out in the Te-based thin films.

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Reliability Assessment Criteria of Power Light Emitting Diodes for Lighting fittings (조명용 Power LED의 신뢰성평가기준)

  • Park, Chang-Kyu;Jeong, Hee-Suk;Jeong, Hai-Sung;Baik, Jai-Wook
    • Journal of Applied Reliability
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    • v.9 no.3
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    • pp.219-231
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    • 2009
  • Power light emitting diodes(LED) for lighting fittings are so much environment-friendly, highly reliable and consume less energy that they are widely used at home and in industries such as electronics, telecommunications and industrial machineries. However, they are exposed to a very diverse environment and consists of complex components and, therefore needs careful approach to the enhancement and assessment of reliability of the item. In this article reliability assessment criteria for LED are established in terms of performance assessment test, reliability assessment test and accelerated test.

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Effect of Nutrient Composition and $GA_{4+7}$ on Flower Quality and Bulb Development in Hydroponics of Cut Tulip

  • Suh, Jeung-Keun;Lee, Jung-Chul
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 2001.04b
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    • pp.51-56
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    • 2001
  • This study was carried out to research the effect of nutrient composition and GA4+7 on growth, flower quality and bulb development in special hydroponics of cut tulip. Flowering of 'Cassini' was markedly accelerated by standard+GA4+7, K200+GA4+7, N250+GA4+7 treatment, last internode was increased by N250 as compared with other treatment. For 'Christmas Marvel', flowering was promoted by K250+GA4+7, last infernode and total length were also increased with K250+GA4+7 as compared to other treatment. For 'Golden Apeldoorn', flowering was accelerated by K200+GA4+7, last internode was increased with N300+GA4+7 treatment and total length was increased in N250+GA4+7 treatment as compared with the standard plants. Bulb weight and number of 'Cassini', 'Christmas Marvel'and 'Golden Apeldoorn' were decreased by GA4+7 as compared to non-treatment, and bulb diameter was not affected by GA4+7.

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The purpose of this study is marketing strategy of foodservice industry. (외식산업의 환경변화에 따른 마케팅전략에 관한 연구)

  • 김미자;정지원
    • Culinary science and hospitality research
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    • v.3
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    • pp.57-81
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    • 1997
  • Recently foodservice industry marketing environment changes rapidly and the qualitic change of demand is accelerated from high growth phase to low growth on industrial environment. To actively competely with the foreign brands that runs with the developed management skills and enough fund, the domestic should classify the customers first and develop the menu. To introduce the modern management technique to pursue the management utility by establishing the market segmentation forcusing the target market and discriminating strategy of menu and service. The method of this study is focused on the changes of foodservice industrial environment and alternatives.

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Deadlock-free Routing of an AGV in Accelerated Motion (가감속을 고려한 교착없는 AGV 주행경로설정)

  • Choe, Ri;Park, Tae-Jin;Ryu, Kwang-Ryel
    • Journal of Navigation and Port Research
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    • v.30 no.10 s.116
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    • pp.855-860
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    • 2006
  • In the environment where multiple AGVs(Automated Guided Vehicles) operate concurrently in limited space, collisions, deadlocks, and livelocks which have negative effect on the productivity of AGVs occure more frequently. The accelerated motion of an AGV is also one of the factors that make the AGV routing more difficult because the accelerated motion makes it difficult to estimate the vehicle's exact travel time. In this study, we propose methods of avoiding collisions, deadlocks, and livelocks using OAR(Occupancy Area Reservation) table, and selecting best route by estimating the travel time of an AGV in accelerated motion. A set of time-driven simulation works validated the effectiveness of the proposed methods.

A semantic Study on Environmental-friendly of Interior Architecture materials (실내건축재료의 환경친화에 관한 의미론적 고찰)

  • 강승모;권자인
    • Korean Institute of Interior Design Journal
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    • no.28
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    • pp.117-123
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    • 2001
  • In 1990s, interest on Environment has been increased and Environment-oriented consumer's economic power accelerated the trend of preference for 'Environment-friendly material'. Moreover, the concept of 'Sick Building' Syndrome has been spread to the public and solution for the syndrome is required. 'Environment-friendly material'means that the material used is not harmful for the user's health, and on top of that, causes least harm to the environment during production/scrap process of the material itself. Decision of designers and architectures, as a result, is really crucial tot he environment issues. Above all, selecting the most environment-friendly material and design among possible candidates is natural and cost saving way. In the paper, couple of Evaluation Criterium for Material Selection are analyzed and objective linkage has been identified. With the result of analysis, methodology to minimize damage on environment during whole life cycle of the Interior Design has been sought for.

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