• The Journal of Engineering Geology
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• v.13 no.3
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• pp.345-358
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• 2003

Recently, the reuse of coarse aggregate derived from demolished concrete was introduced into practice with two environmental aspects: protection of natural sources of aggregate and recycling of construction waste. However, recycled aggregate has been used for the very limited application such as subbase material for pavement and constructional filling material because it was considered as low quality constructional materials. In the present study, in order to examine the possibility that recycled aggregate can be used for concrete mixing, we conducted various experimental tests to identify mineralogical, chemical and mechanical properties of recycled aggregate and to determine the workability and mechanical properties of recycled aggregate concrete (RAC). The cement paste and mortar contained in recycled aggregate significantly affect the basic mechanical properties of aggregate and the workability and mechanical properties of RAC. However, RCA mixed with the proper replacement ratio of recycled aggregate shows the comparable compressive strength and freeze and thaw resistance to those of normal concrete. Therefore, it is considered that recycled aggregate can be widely used for concrete if the cement paste and mortar can be efficiently removed from recycled aggregate and/or if the effective replacement ratios of recycled aggregate are applied for mixing concrete.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1618-1625
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• 1993

In the transmission of image using the lossless Laplacian pyramid coding, the image quality of the last hierachy is almost same regardless of the bit rate of each hierachy. However, at the higher hierachy with low resolution, it is varied according to bit rate of each hierachy. In this paper, optimum bit allocation to achieve better image at the higher hierachy and minimize the distortion at the last hierachy was proposed. More efficient progressive transmission was shown to be possible by experimental results of higher PSNR and better image quality at the hierachy with low resolution.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.177-178
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• 2009

LCD(Liquid Crystal Display)가 발전하면서 많은 브라운관 TV가 LCD TV로 바뀌고 있다. 하지만 LCD의 특성으로 인해 동영상 재생시 느린 반응속도를 보이며 문제점들이 발생한다. 이를 해결하기 위한 방법으로 화면 재생율을 향상시키는 120Hz를 도입하고 있다. 본 논문에서는 120Hz 화면 재생율에 맞춰 기존의 60Hz 영상을 120Hz 영상으로 바꿀수 있는 화면보간기법을 제안한다. 제안하는 알고리즘은 생성되는 프레임 전후의 프레임 블록을 이용해 블록매칭을 이용한 단방향 움직임 추정을 이용하여 지역 움직임 추정을 한다. 이후 지역 움직임 추정에서 찾지 못한 모션 벡터를 전후프레임 픽셀 평균과 영향이 큰 모션 벡터를 선택하여 적용시키는 적역 움직임 추정으로 프레임을 완성시키는 알고리즘이다. 제안하는 알고리즘을 이용하여 다양한 해상도의 영상비교를 시행하여 좋은 결과를 얻었다.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.79-82
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• 1985

The experiment of protoplast regeneration and reversion were undertaken to provide a basic techniques for protoplast manipulation. Protoplasts of Pleurotus florida and Pleurotus ostreatus were reverted to normal hyphal growth and the reversion frequency of both fungal protoplasts were $0.24{\sim}3.19%$. Reversion medium stabilized with 0.6 M potassium chloride and sucrose was better than the other stabilized one. The protoplast reversion frequency was increased when various amino acid and vitamin compounds were added to the hypertonic mushroom complete agar medium.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.154-159
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• 1992

Forniation ancl ~regcncration oi' conitlial pro1oplast of Pc, ti~i.rlli~in~~~ c~rr~~culo.hryupmel.- - czllulolytic Ihngus. were examined. By using Novozyme 134(1'!/0 w/c) as a cell wall lytic enzyme. the highest yield of protopl;~sts exceeding 501%, war obtained from the qwollen conidiosporcs preincubatrd in the minimal medium containing 2-tleoxy-D-glucose(2-UC;. 75 pglml) for 10-11 11. No protoplast were obtained horn dormant spores. The regeneration frequency of the protoplasts was 49.2'!11. which was higher than that of mycclium originated protoplast (4.6-17.X1X, . in 0.6 M MgS04. pH 5.6). 'l'lie best osmotic stahilizcr ror the isoaltion and regcueration of thc protoplast was 0.6 M iimmonium sulfatc and 0.6 M magnesiuni sulfhte. respectively. 'I'lie process of the protoplast isolaiton l'ro~n swollen cnnirliospore ancl regeneration ha\, ing two pattcrns from protoplast were obsen'etl through light microscope.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.33-39
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• 1992

Effects of buprofezin, a chitin synthesis inhibitor of insects, on mycelial growth, protoplast formation and reversion of Coriolus versicolor, Ganoderma applanatum and G. lucidum were investigated. The mycelial growth of C. versicolor, G, applanatum and G, lucidum was severely inhibited by buprofezin treatment, and the inhibition rate severely as the concentration of the buprofezin increased. Aerial mycelia and oidia formation of the mushrooms were increased by buprofezin treatment, but mycelial morphology was not changed. The rate of protoplast formation and reversion of G, applanatum was greatly increased by the treatment of the buprofezin, while that of G. lucidium was decreased. The rate of protoplast formation of C. versicolor was also increased when buprofezin was added to the medium, but the rate of protoplast reversion was not affected by the treatment, From the results obtained in this experiment, we found that the rate of protoplast. formation and reversion was increased by the treatment of the buprofezin in the mushrooms such as C, versicolor and G, applanatum, whose mycelial growth was fast on the medium, while that of G. lucidum, whose mycelial growth was relatively slow, was decreased by the treatment.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.385-392
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• 2005

The object of this study is to prove the quality and reliability of recycled aggregate concrete by finding a way to improve the durability of the material through the experiment on the accelerated carbonation, freezing and thaw, and drying shrinkage, analysing the influence on the durability to Promote more active use of recycled aggregate concrete. The result of study as follows. (1) Resistibility to the freeze and thaw of the recycled aggregate concrete showed relative dynamic modulus of elasticity over $90\%$ which is very good, and all cycles show $99.2{\~}91.0\%$ dynamic modulus of elasticity which is improved compared with the $97.5{\~}90.6\%$ relative dynamic modulus of elasticity of ordinary concrete made of broken stone. (2) Carbonated thickness of the recycled aggregate concrete and the normal concrete was similar or it appeared with the tendency which it diminishes more or less. (3) Length change rate in drying contraction of the recycled aggregate concrete made of the recycled aggregate was lower than the ordinary concrete made of the broken stone by $18.5{\~}3.9\%$ in all blending.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.482-484
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• 2008

본 연구는 신재생에너지 발전차액지원제도의 기준가격이 보급규모를 제어할 수 없는 제도적 한계를 보완하여 시스템적으로 기준가격이 조정될 수 있는 유연감소율 메커니즘을 제안한다. 제안한 유연감소율 메커니즘은 시장의 보급규모에 따라 기준가격을 시스템적으로 조정함으로써 시장여건의 반영체계를 갖추어 가격조정에 대한 이행당사자간의 이해상충 문제를 완화하는 수단으로 활용될 수 있다.

• International Journal of Highway Engineering
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• v.7 no.2 s.24
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• pp.13-22
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• 2005

Using recycled aggregate from demolished concrete structures provides a peat opportunity fur conserving natural resources. In many parts of world, virgin aggregate deposits have been depleted, and transporting aggregates over long distances can be much more expensive than using a low-cost recycled aggregate. In Korea, about 7-million tons of concrete occurs annually, out of this, about 2-3 million tons are available for recycling. This study is to present the method of utilizing the recycled aggregate. The recycled aggregate concretes were made for compressive strength test, flexural strength test and fatigue test using w/c of 40, 50 and 60%. The replacing rates of recycled aggregate to virgin aggregate were 0, 25 and 50%. The purpose of this study is to compare the fatigue lift of recycled aggregate concrete with that of virgin aggregate concrete. It was shown that the fatigue life of recycled concrete was function of recycled aggregate replacement ratio and water cement ratio.

• Electric Engineers Magazine
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• s.382
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• pp.20-21
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• 2014

우리나라의 화석연료 의존율은 80%를 넘는 수준이다. 화석연료의 고갈은 전 세계적으로 큰 혼란을 불러올 것으로 예상되기 때문에 세계 각국은 신재생에너지 시장 개척에 사활을 걸고 있다. 이러한 신재생에너지 가운데 안정적인 차세대 에너지원으로 각광받고 있는 연료전지에 대해 알아보자.