• Korean Journal of Microbiology
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• v.22 no.1
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• pp.67-72
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• 1984

Effects of pheromone and GMP on the protein synthesis during development of Stigmatella aurantiaca under the starved condition were examined and compared with that of light on the same process. Light, pheromone, and GMP induced at least three, five, and two kinds of new proteins, respectively; one of them having molecular weight 30,0000 was the only protein present in all cases. It was also observed that there are an increase or decrease in the expression and disappearance or reappearance of several vegetative proteins during development under the each condition. It may be deduced from all these results that the mechanism of development in Stigmatella aurantiaca is a complex on which may be affected not only by a class of development-specific proteines but also by other classes of new proteins as well as several classes of proteins present in the vegetative cells.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.54-64
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• 2007

This study is a fundamental research in order to establish the design code of recycled aggregate concrete structure. The structural properties of recycled aggregate concrete such as flexure, shear, fatigue, compression, and bond development are experimentally investigated and confirmed. In this study, laboratory-scale reinforced concrete beam, column, and pull-out test specimens using recycled coarse aggregate are manufactured. Then, the structural performances of recycled aggregate concrete according to replacement ratios of recycled coarse aggregate are evaluated. Also, finite element analysis using commercial code DIANA is carried out to predict the test results and the analysis results are compared with test results in this study. Structural test results showed that the structural performances of recycled aggregate concrete specimens with 60% replacement ratio are reduced by approximately 15-20%. These results indicated that the replacement ratio of recycled coarse aggregate within 30% is a suitable to use for structural members. The results of finite element analysis showed that the specimens with 30% replacement ratio possessed similar or more excellent structural performance than normal concrete specimens. However, recycled aggregate concrete with 60% replacement ratio of recycled coarse aggregate must be carefully considered for structural applications due to significant decrease of the failure loads.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.6
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• pp.782-790
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• 2000

The mainly used polymeric material for the denture is PMMA because of its cost and easiness to handle. So it was widely used material among dentists for past decades. But the acrylic-based denture materials have several common weak points such as shrinkage after curing and lack of strength. In order to solve these problems, we adapted one of hybrid system using acrylic polymer and vinyloligosilsesquioxane(POSS). POSS, which is a well known expandable monomer during polymerization process, may eventually suppress volumetric shrinkage. And the hybrid system makes it possible for the polymer to be stable in various severe conditions. Eight different kinds of samples were designed and synthesized. Each samples were characterized with dynamic mechanical analyser(DMA) to confirm their thermodynamic properties, fractured to analyze the cross-sectional morphology of the samples. And elongation, flexural and impact tests were also executed to evaluate the mechanical properties of the samples. From the results, hybrid composites had well defined crosslinked network structure compared to the widely used denture materials, and the mechanical strength improved without changing any surface condition as increment with POSS ratio in hybrid system. Fractured morphology showed homogeneous surfaces in spite of mutli component system, therefore we can conclude that the adoption of the POSS brought the reinforcement of the denture resin.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.302-308
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• 2005

This study was carried out to obtain the basic informations on the characteristics of gametophytes formation and embryo developement in Dicentra spectabilis. Microspore mother cells developed from archesporial cells, start meiosis when flower bud length reaches around 1 mm, formed tetrahedral type tetrad. The 4 microspores were separated. They were developed to male gametophytes, respectively. Megaspore mother cells were observed when flower bud length was $4{\sim}5\;mm$. The developemental type of megaspore was polygonum and embryo sac was amphitropous. Three large and distinctive antipodals did not degenerated and remained after embryo sac was developed. When the male and female gametophytes was fully developed, the length of stamen and style was very similar or stamen was shorter about 0.5 mm than that of style. This result indicates that self-fertilization can be occurred in this species. After fertilization, developing zygotic embryos showed various stages of development from globular to cotyledonary embryos, and zygotic embryo in seed scattering time seemed to have an early cotyledonary stage.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.238-268
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• 1992

Since rural people migrated to urban area as a result of rapid industrialization in Korea, a significant proportion on agricultural labor farces has consistently reduced and therefore incurred labor shortage in rural area which might aggravate the farm household's economy. This sutdy suggests a long run plan of supplying agricultural machines for forage cultivation based on the survery of 102 livestock farm housecholds conducted in 1987, aimed at curtailing the labor costs which would contribute to improving the livestock farming management. The results of this study are as follows: 1. Among the 102 livestock farm household surveyed, 50 farm housecholds were found to cultivate 398a of grassland on average while other 52 farm households produced the forage on the 169a of land under cultivation averagely. 2. Over 50 percent of farm houseolds were reported to have their own agricultural machine for harvesting and cutting, however rates of mechanization in other operations such as mowing and sowing were less than 20 percent. 3. There were more than 50 percent of livestock farm households who have shown their intention to buy and operate their own farming machines when proprer opportunities are given. 4. In order to estimate the long-run demand for agricultural machines for livestock farm household considering current mechanization procedure, data for the machine's optimal capacty, growth of arable acreage for feed stuffs was collected and analyzed. 5. Based on the estimated demand, long range supply plan of livestock farming machines for the period of 1990-2010 was suggested. 6. Finally, measures for technological developement and finanacial support were suggested to implement so as to encourage the farmers' adoption of agricultural machines, and to achieve the goal of mechanization planning for the livestock farm household.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.184-190
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• 1993

This study was carried out to investigate the appropriate medium and constitutionof growth regulators for somatic embryogenesis for development of rapid mass propagation system via somatic embrygenesis in Rehmennia glutinosa. Embryogenic callus formation from leaf explant was more effective when 4mg / l BA with 0.5mg / l NAA than that of treated with only auxins or cytokinins. LS medium was suitable for embryogenic callus formation. LS medium with 4mg / l BA with 0.5mg / l NAA was effective for the maintenance and proliferation of embryogenic callus. In suspension culture, addition of 1mg / l BA to LS medium was proper for somatic embryogenesis. The highest rate of shoot developement form cotyledon stage embryo was obtained in 1/2 LS medium and plantlet survived by 75% after transplanted to the soil. after 4 weeks.

• Magazine of the Korea Concrete Institute
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• v.8 no.6
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• pp.235-243
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• 1996

The mechanical behavior ot concrete is strongly influenced by various scenarios of crack initiation and crack propagation. Recently. the study of the interface fracture and cracking in interfacial regions is emerged as an important field, in the context of the developement of high performance concrete composites. The crack path criterion for elastically homogeneous materials is not valid when the crack advances at an interface because. in this case, the consideration of the relative magnitudes of the fracture toughnesses between the constituent materials and the interface are involved. In this paper, a numerical method is presented to obtain the values of two interfacial fracture parameters such as the energy release rate and the phase angle at the tip of an existing interface crack. Criteria based on energy release rate concepts are suggested for the prediction of crack growth at the interfaces and an hybrid experimental-numerical study is presented on the two-phase beam composite models containing interface cracks to investigate the cracking scenarios in interfacial regions. In general, good agreement between the experimental results and the prediction from the criteria is obtained.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.413-416
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• 2005

Developement of computer and digitalizing of medical implement are being caused digitalizing of medical image. Medical Images are being managed more by PACS. In this situation comes out many problem about ownership, the right of properity of the medical images and notice wheather the data are modified. Digital watermarking can solve this problem. The proposed schemes have a two weak point that Non-blind method need a original image and Blind method use gaussian watermarking. In this paper, we propose a blind watermarking using binary image in order to easily recognize result of watermark This proposed scheme using wavelet transform and Circular Input method that input in medium-band of frequency domain.

• Archives of design research
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• v.18 no.3 s.61
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• pp.219-222
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• 2005

This study is for the design developement of wall mount air purification device used for pleasant and clean resident environment. As more people have the high standard of living, they are interested in the air quality of indoor environment, since it is believed its relationship with human health. Now the social demand of air purifier is increasing. Its market is growing and there are various design products in the market. However, dominant current products are floor-based standing type, it needs much spaces to install for the air inhalation and exhaust. Therefore, this product provides the space-saved design. Its concept comes from existing wall mount type air conditioners. The effect of wall decoration is another merit of this proposal. It has an easy filtering change and cleaning system and a simple operation of multiple functions. This product also has the perfect-matched slim design that is consist of natural curves with rectangle for any indoor spaces.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.152-159
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• 2005

The method of induction noise reduction can be classified by using passive control or active control method. However, the passive control method has a demerit to reduce the effect of noise reduction to low frequency (below) 500Hz) range and to be limited in a space of the engine room. Whereas, the active control method can overcome the demerit of passive control method. The algorithm of active control is mostly used in LMS (Least-Mean-Square) algorithm because it can obtain the complex transfer function easily in real-time. Especially, Filtered-X LMS (FXLMS) algorithm is applied to an ANC system. However, the convergence performance of LMS algorithm could not match if the FXLMS algorithm is applied to an active control of the induction noise under rapidly accelerated driving conditions. So, in order to solve the problem in this study, the Moving Bandpass Filter(MBPF) was proposed and implemented. The ANC using MBPF for the reduction of the induction noise shows that more noise reduction as 4dB than without MBPF.