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Effects of absorbed radioactive sulfur (S35) in plant cell.(III) Effects of temperatures on amylase activity and growth of rye seedlings grown in solution of S35 (식물에 미치는 방사성 동위원소 S35의 영향에 대하여 (제3보) 발아호밀의 Amylase Activity 및 생장에 미치는 온도의 영향에 대하여)

  • 홍순우
    • Journal of Plant Biology
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    • v.11 no.1
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    • pp.1-6
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    • 1968
  • The effects of the different temperatures on the amylase activity and growth rate of the rye seedling grown in the solutions containing radioactive sulfur- 35 were studied. The amylase activity of the coleoptiles obtained from the seedlings grown in the solutions of S-35, at 14$^{\circ}C$, appeared to be strongly stimulated in comparison to the control, but the culture temperatures of 22$^{\circ}C$ and 3$0^{\circ}C$ showed the decrease in the amylase activity. The amylase activity of the grains treated with the low intensity of the ratioactive material didn't show clear changes, at any culture temperatures, but the amylase activity of the grains treated with the high intensity of S-35, 50$\mu$c, showed definite decline at the elevated culture temperature, 3$0^{\circ}C$. Similar effects was also found in the growth of the seedlings. However, we would consider the effects of the radioactive materials on the acticity of the amylase and the growth of the seedlings are resulted from the accumulation of the much amount of the radioactive materials, and this accumulation rate depends upon actually the elevation of the culture temperature.

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A Study of Photoshop Retouching Technique for Beauty Make-up (뷰티 메이크업을 위한 포토샵 리터칭 기법 연구)

  • Kwon, Hyun-Ah
    • The Research Journal of the Costume Culture
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    • v.14 no.6
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    • pp.932-944
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    • 2006
  • With supplied computers and the development of information and communication thropugh the Internet, the space of personal home pages in potal sites has been filled with photos taken by digital cameras, and 'the introduction of privacy' done in the personal home pages has become a general trend in society. As the use of Photoshop, available to edit and modify digital photos, in this social atmosphere, has grown general, they have shown their interest in the retouching technique of Photoshop. Computer graphics, marked based on the treatment of a variety of information into pictures or a technology to mark it, recently various application methods have been found in make-up. Especially, Adobe Photoshop, used to edit and modify images, is a sofetware program proper to perform beauty make-up in correcting and creating images in an effective way. The purpose of this study is to express each factor in Adobe Photoshop CS2 about the beauty make-up. As a result, I can say, the process that digital image is retouched by Adobe Photoshop CS is similar work to beauty make-up. The process of Photoshop retouching can be used as the materials for educating of make-up and as the materials for presentation of beauty make-up trend. And also we can serve the simulation to the customer before real make-up. Therefore, this study is for the effective performance of diverse beauty makeup integrating retouch technique with Photoshop CS.

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Study on Mechanical and Thermal Properties of Tio2/Epoxy Resin Nanocomposites

  • Kim, Bu-Ahn;Moon, Chang-Kwon
    • International Journal of Ocean System Engineering
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    • v.3 no.2
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    • pp.102-110
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    • 2013
  • The purpose of this study was to improve the properties of epoxy resin using titanium oxide nanoparticles. The effects of particle weight fraction, dispersion agent, and curing agents with different molecular weights on the thermal and mechanical properties of titanium-oxide-reinforced epoxy resin were investigated. In addition, the effect of the particle dispersion condition on the mechanical properties of nanocomposites was studied. As a result, it was found that the glass transition temperature of film-shaped nanocomposites decreased with an in-crease in the nanoparticle content. Because nanoparticles interrupted the cross linkage between the epoxy resin and the amine curing agent, the cross-link density of the epoxy became lower and led to a decrease in $T_g$ in the nanocompo-sites. The tensile strength and modulus in film-shaped nanocomposites also increased with the particles content. But in the case of dog-bone-shaped nanocomposites, the values were not similar to the trend for the film-shaped nanocompo-sites. This was probably a result of the different nanoparticles dispersions in the epoxy resins resulting from the respective-thicknesses of the film and dog-bone-shaped samples.

Microwave Sintering Behavior and Electrical Properties of BaTiO$_3$ Ceramics (BaTiO$_3$ 세라믹의 마이크로파 소성 및 전기적 특성)

  • Bai, Kang;Kim, Ho-Gi
    • Journal of the Korean Ceramic Society
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    • v.35 no.11
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    • pp.1203-1211
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    • 1998
  • The microwave sintered BaTiO3 samples were obtained by using the microwave sintering device which can precisely control the sintering temperature and the sinter time by using IR optical thermometer and PID temperature controller. During microwave sintering the internal temperature of samples were mesur-ed by the optical fiber thermometer to compare the sintering behaviors between microwave- and con-ventionally sintered ones. The former showed the faster rate of grain growth with sintering time and the larger grain size than the latter. Also they showed the similar pattern of dielectric properties with tem-perature changes from 2$0^{\circ}C$ to 16$0^{\circ}C$.

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Support vector machine for prediction of the compressive strength of no-slump concrete

  • Sobhani, J.;Khanzadi, M.;Movahedian, A.H.
    • Computers and Concrete
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    • v.11 no.4
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    • pp.337-350
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    • 2013
  • The sensitivity of compressive strength of no-slump concrete to its ingredient materials and proportions, necessitate the use of robust models to guarantee both estimation and generalization features. It was known that the problem of compressive strength prediction owes high degree of complexity and uncertainty due to the variable nature of materials, workmanship quality, etc. Moreover, using the chemical and mineral additives, superimposes the problem's complexity. Traditionally this property of concrete is predicted by conventional linear or nonlinear regression models. In general, these models comprise lower accuracy and in most cases they fail to meet the extrapolation accuracy and generalization requirements. Recently, artificial intelligence-based robust systems have been successfully implemented in this area. In this regard, this paper aims to investigate the use of optimized support vector machine (SVM) to predict the compressive strength of no-slump concrete and compare with optimized neural network (ANN). The results showed that after optimization process, both models are applicable for prediction purposes with similar high-qualities of estimation and generalization norms; however, it was indicated that optimization and modeling with SVM is very rapid than ANN models.

Limit-current type zirconia oxygen sensor with porous diffusion layer (다공성 확산층을 이용한 한계전류형 지르코니아 산소센서)

  • Oh, Young-Jei;Lee, Chil-Hyoung
    • Journal of Sensor Science and Technology
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    • v.17 no.5
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    • pp.329-337
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    • 2008
  • Simple, small and portable oxygen sensors were fabricated by tape casting technique. Yttria stabilized zirconia containing cordierite ceramics (YSZC) were used as a porous diffused layer of oxygen in pumping cell. Yttria stabilized zirconia (YSZ) solid electrolyte, YSZC porous diffusion layer and heater-patterned ceramic sheets were prepared by co- firing method. Limit current characteristics and the linear relationship of current to oxygen concentration were observed. Viscosity variation of the slurries both YSZ and YSZC showed a similar behavior, but micro pores in the fired sheet were increased with increasing of the cordierite amount. Molecular diffusion was dominated due to the formation of large pores in porous diffusion layer. The plateau range of limit current in porous-type oxygen sensor was narrow than the one of aperture-type oxygen sensor. However limit current curve was appeared in porous-type oxygen sensor even at the lower applied voltage. The plateau range of limit-current was widen as increasing the thickness of porous diffusion layer of the YSZ containing cordierite. Measuring temperature of $600{\sim}650^{\circ}C$ was recommended for limit-current oxygen sensor. Porous diffusion layer-type oxygen sensor showed faster response than the aperture-type one and was stable up to 30 days running without any crack at interface between the layers.

In vitro study of Streptococcus mutans adhesion on composite resin coated with three surface sealants

  • Kim, Da Hye;Kwon, Tae-Yub
    • Restorative Dentistry and Endodontics
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    • v.42 no.1
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    • pp.39-47
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    • 2017
  • Objectives: Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. Materials and Methods: Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). Results: Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. Conclusions: The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.

A Comparison of the Dielectric Behavior of Aromatic and Aliphatic Polyurethanes in Relation to Transitional Phenomena

  • Kim, Chy Hyung
    • Transactions on Electrical and Electronic Materials
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    • v.18 no.4
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    • pp.211-216
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    • 2017
  • The dielectric properties of two polyurethanes (PUs) with different hard segments, i.e., aromatic methylene di-p-phenyl diisocyanate (MDI) and aliphatic hexamethylene diisocyanate (HDI), were investigated in the temperature range of -100 to $100^{\circ}C$ and in the frequency range of 1 Hz to 3 kHz. The ${\alpha}$-relaxations induced by the glass transition of the equivalent soft segments in the two PUs occurred at relaxation times of ${\tau}=3.46{\times}10^{-3}s$ for MDI-PU and ${\tau}=3.39{\times}10^{-2}s$ for HDI-PU at $-20^{\circ}C$, in accord with the temperature-frequency superposition principle, resulting in similar shifting factors. However, different I-relaxations were observed for the two PUs. The I-relaxation of MDI-PU occurred due to the mobility of the chain extenders near $80^{\circ}C$ with a slower shifting rate than the ${\alpha}$-relaxation. On the other hand, I-relaxation arising from both the extender and the unconstrained hard segments of HDI-PU occurred at $70{\sim}100^{\circ}C$, indicating complicated dielectric behavior due to partial interaction with the ${\alpha}$-relaxation at high frequencies. Thus, the I-relaxation of HDI-PU did not follow the superposition principle. The dielectric behaviors of the PUs were mainly influenced by their phase transitions, which were affected by the structure and components of the materials.

A Study on the Remodeling for Improvement of Acoustic Performance at Indoor Swimming Pool (실내수영장 음향성능 개선을 위한 리모델링에 관한 연구)

  • Kim, Nam-Don;Kim, Dae-Goon;Kim, Jae-Soo
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.3
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    • pp.87-94
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    • 2009
  • Recently, in accordance with the interesting on well-being as well as the revitalization of living athletics, it is current tendency that people who use the swimming pools are on increasing. However, because the most of indoor swimming pools have ever used the reflection finishing materials likely as the tile due to the property of its hydrophilic space, the inside of indoor swimming pool is vibrating too much, and some problem which the voice and music do not delivering clearly is occurring when swimming lessons or underwater aerobics(synchronized swimming) and swimming game. Based on such viewpoint, locating the object on actually built indoor swimming pool, this Study has ever grasped its physical acoustic property, and finally designed the indoor swimming pool that contains an optimum acoustic condition, by remodelling it through an acoustic simulation. It is considered that such study result could be utilized as the useful materials when constructing the similar indoor swimming pool, hereafter.

A Study on the Electrical Properties for the Insulation Design of a Conduction-Cooled HTS SMES (전도냉각 HTS SMES 절연설계를 위한 전기적 특성연구)

  • Choi, Jae-Hyeong;Kwag, Dong-Soon;Cheon, Hyeon-Gweon;Baek, Seung-Myeong;Kim, Hae-Jong;Seong, Ki-Chul;Kim, Sang-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.226-227
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    • 2006
  • The conduction-cooled HTS SMES is operated in cryogenic and high vacuum condition. Thus, Insulation design at cryogenic temperature and high vacuum is a key and an important element that should be established to accomplish miniaturization that is a big advantage of HTS SMES. Therefore, we need active research and development of insulation concerning application of the conduction-cooled HTS SMES. Therefore, in this study, we experimented about insulation characteristic high vacuum and cryogenic similar to driving condition of SMES system. Also, investigated about insulation characteristic of suitable some materials to insulator for conduction-cooled HTS SMES. As this results, we possessed basis data for insulation materials selection and insulation design for development of 600 kJ class conduction-cooled HTS SMES.

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