• 펄프종이기술
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• 제29권1호
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• pp.13-25
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• 1997

To establish the weed control method without herbicide and weeding work, mulch paper was developed from domestic old corrugate container. Basis weight of mulch paper should be above 120 g/$m^2$ to guarantee the mechanical properties. It was concluded that polyamide polyamine epichlorohydrin was desirable to improve the wet strength of mulch paper and the optimum addition level was about 1.5% on the basis of oven dry pulp. The mulch paper was found to be effective in controlling paddy weeds. For the complete weed control the mulch paper should be sustained without decomposition over 45 days. As the paper mulching reduced the soil temperature, the mulch paper was required to improve the penetration of radiant heat.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1993년도 추계학술발표회논문집
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• pp.97-102
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• 1993

The application of epxy composite materials for the outdoor insulating systems has some significant advan-tages compared with conventional inorganic materials, that is low weight in combination with high mechanical strength, small dimensions and design versatility. The paper describes the results of high voltage investigations carried out different aging types of epoxy resin insulator and silicone grease coating. The insulators have been exposed 3000 hours to weather-o-meter and 12 months to outdoor. In this connection, the main study of paper is form the basis of develop-ment of principal technologies of epoxy composites which ard: (1)manufacturing of insulator, (2)high vol-tage testing under dry and wet condition, (3)mechani-cal properties, (4)accelerated weather-ometer test and outdoor exposed, artificial polution.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.103.1-106
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• 2003

Recently, it is increased on the concern for the reuse of waste concrete because of the shortage of natural aggregate and the increase of waste concrete. And recycled coarse aggregate is used variously, but the existing wet method producted recycled fine aggregate has problems like the high price facilities, the long time progress of the work and recycled fine aggregate of poor. The aim of this study is to investigate the possibility of the method of dry producted high qualities recycled fine aggregate The results of this study have shown that the possibility of the method of dry is certificated as the dualities of recycled fine aggregate satisfied the KS and the compressive strength of mortar was similar to plain.

• 한국전기전자재료학회논문지
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• 제18권11호
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• pp.1014-1018
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• 2005

The purpose of this study is to obtain strong bond strength at the interface between piezoelectric substrates and semiconductor thin films to be applied for the manufacture of high-performance acoustic wave semiconductor coupled device. For this purpose, we have compared and examined the effects of different surface treatment methods on hydrophile properties at the surface of the piezoelectric substrates. Moreover, we have observed the effect of microwave and laser on the elimination of water molecules at the interface. As for the piezoelectric substrates, dry method for surface treatment was found to be superior in the control of hydrophilicity of the surface compared to wet method. On the other hand, both microwave and laser were found to be effective in the elimination of water molecules in the interface.

• KCI Concrete Journal
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• 제14권2호
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• pp.61-68
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• 2002

An experimental investigation on the flexural fatigue behavior of a RC bridge slab retrofitted with Carbon Fiber Sheet (CFS) is presented. The test slab was almost identical to the slab of a highway viaduct in terms of the amount of reinforcement, quality of concrete and thickness of the slab, which was 18cm. Repeated load corresponding to 3.0, 4.5 or 6.0 times of the design load was applied to the test slab. Normal type and high-elastic modulus type of CFS were used for strengthening. The test slabs were loaded in dry or wet condition. Two different types of an-choring system were adapted. Some of the test slabs were damaged by the repeated load and retrofitted by CFS, then loaded again to see the improvement of the fatigue life. Infrared Thermography was also performed to investigate the debonding condition of CFS. From the test results, Carbon Fiber Sheet can be applied to the RC bridge slabs as a feasible retrofitting material.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.19-20
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• 2019

The purpose of this study is to apply a test method that evaluates durability under wet environment rather than the strength of the material itself to reflect the environment of use and field conditions of silic acid powder applied waterproof material, and to prepare a foundation data for differentiated performance criteria through test verification.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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• pp.254-257
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• 2004

Fiber placement system (FPS) carries out an advanced composites process which orients high strength reinforcing fibers in specific directions. The process includes wet winding, thermoset tape winding, thermoset prepreg placement and thermoplastic prepreg placement. FPS have the advantage of tape laying and filament winding with computer control and software. Using FPS can reduce costs, cycle times, structural weight, and handwork/rework when manufacturing composite parts. The sleeve extension is a part of the helicopter rotator systems. In this study, The sleeve extension composites were manufactured using FPS and tensile properties of this composites were characterized using universal testing machine(UTM).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.525-528
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• 2006

Recently, Korea government prepared Act on facilitation of construction waste recycling in December 2003 for effective recycling of rapidly increasing construction wastes, and has enforced the Act on Jan. 2005. This Act limits the definition of recycled aggregates to the aggregates which obtained quality certificate and for this purpose, government has operated quality standard and certificate system of recycling aggregate. The objective of this experimental study is to evaluate the mechanical properties of recycled coarse aggregate concrete according to curing method by ready-mixed concrete. Compressive strength ratio of recycled aggregate concrete under air-dry curing/wet curing was $74{\sim}91%$. KCI code for conventional concrete overestimated elastic modulus for recycled coarse aggregate concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.166-167
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• 2013

Bottom ash, which is discharged through a wet process in a thermal power plant, contains much unburned coal due to quenching and much salt due to seawater. However, dry bottom ash discharged through a dry process contains low unburned coal and salt, and has light -weight due to many pores. Therefore, it is expected that it can be used as lightweight aggregate. This study deals with the basic properties of concrete used dry bottom ash as coarse aggregate. As a results, the concrete having high content of dry bottom ash aggregate showed high slump by using water reducing agent and its air content was within 5±1.5% as designed value, similarly to normal weight concrete. It also showed a lower compressive strength than 100% of crushed stone.

• 대한치과의사협회지
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• 제49권2호
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• pp.85-94
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• 2011

In the filed of Dentistry, minimally invasive treatment modalities are new trend for conservation of natural teeth. Of them, laminate veneer and resin bonded fixed partial denture belong to restoration procedures. In this review, survival rates of each modalities and cause of unserviceability are analyzed, and criteria for success are presented. To get successful results of minimally invasive restoration, plenty of enamel layer, thin and strong materials, and high bonding strength are essential under cyclically loaded wet oral condition. Newly tried design of minimally invasive technique nowadays have to be evaluated only on the basis of requirement for long-term success.