• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.407-408
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• 2011

Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

• Korean Institute of Interior Design Journal
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• v.23 no.6
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• pp.22-32
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• 2014

Development of digital technology, which is individualizing and differentiating the world, makes time and space facilitate multi-layering in the contemporary society. It gives a large influence on the contemporary architecture that inducing the visual and spatial experience. Also, It generates new images through the skin of architecture, which implies the contingent and fluid characteristics. These phenomenon show that various parameters are working on the architectural skin simultaneously. Such complexity make the structure of open space and diversity that are homogenized and synchronized. Like this, the architectural skin implies 'multiplicity': qualitative difference which is enable to change and create new images. This characteristic generates instant images changing variously and semantics constantly by the function of skin as a filter. Also, the architectural skin integrates or relocates of relationships between the various information and elements appearing in contemporary society in order to escape the customary relationship between internal and external. Furthermore, the inside and outside of the mixture as a collection of sense has been recognized as one image. This image of mixture consists of one unified continuous integration and extend the meaning of a fluid interface not just surface of the building. The skin of the contemporary architecture is very technical, so its meaning and role is expanded as a complex that exchange interaction. This means that the skin itself has functional elements of the integrated multiple skin to assist. Also it can form a multi-layered relationship and act as a wide range of interfaces depending on the perception of the observer. Therefore the multiplicity of the architectural skin indicates the importance as a boundary that generate images of new life through the sensory perception and implicit force. And it shows potential as the intermediary to try to communicate.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.31.2-31.2
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• 2011

We studied a method of manufacturing an anode to restrict contraction in reducing NiO/YSZ by uniformly mixing. In order to mix Ni and YSZ, a sub-micron Ni core surface was coated at high-speed by a mixture of nano-sized YSZ and a spherical core-shell was subsequently formed. The micron-sized core-shell anode powder was then heat treated at $400{\sim}1,450^{\circ}C$ in an air atmosphere and Ni was extruded and synthesized in nano-size. Subsequently, when the nano-sized mixture of the anode was heat treated and maintained at a temperature of $1,450^{\circ}C$, the anode was manufactured, where Ni and YSZ were uniformly distributed with the nano-structure. According to the nano-sized anode powder synthesis process, Ni particles were oxidized at $400{\sim}500^{\circ}C$ and became spherical by surface tension. In the case of the spherical core Ni powder, the heat treatment temperature rose to $1,250^{\circ}C$ and then a gap between the internal and external pressures occurred due to thermal and tensile stresses. A crack subsequently appeared on the surface, and the heat treatment temperature was increased continuously to increase the pressure gap and then the core Ni extruded as a nano-sized powder, Ni and YSZ uniformly distributed. It was found that the anode of 50~200 nm with a consistent structure obtained in this study has electric conductivity that is approximately 3 times larger than that of a commercial anode.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.6
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• pp.561-566
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• 2019

In the Internet space, integrity and security must be maintained for secure and confidential communication, which ensures reliability between sender and receiver. Cryptography is an important factor in maintaining robustness against external attacks. For this purpose, encryption and steganography methods are used. Steganography is a method of hiding confidential information without making statistically significant changes to digital media. I propose a method of transforming the Hangul-Jamo consisting of choseong, jungseong and jongseong, and inserting them into RGB pixel values of the cover image. In order to improve security, a new blending method was used to hide the altered information in the lowest region. In this case, a mixture of LSB and LDR techniques was applied. PSNR was calculated for image quality. The PSNR of the proposed method is 43.225dB, which satisfies the lowest level.

• Journal of the Korean Society of Costume
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• v.59 no.8
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• pp.82-96
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• 2009

The purpose of this study is to present the basic approach of producing the luxury fashion brands containing of the Korean traditional traits on the basis of traditional transformation with the modern concept, taking the 'Vivienne Tam' 2000's collections. This study has focused on its transformation of the traditional one of China, and made this as the subject of investigation. It's design characteristic could be defined as "modern interpretations of China chic", and it would be divided into two groups. The ingenious mixture of Chinese tradition into the modern chic could be concluded like these. The external characteristics is categorized in the three ways (1) the aesthetic application of the Chinese traditional patterns(dragon, water waves, peony, Japanese apricot flower, bamboo, bats, Chinese characters etc.), (2)the modern application of Chinese traditional costume details(front opening of Chipao, mandarin collar and knot buttons) and (3)the modernization of Chinese traditional technique(knotting, embroidery, beading and paper cutting). To deal with the internal characteristics, (1)the aesthetic mixture of East and West, (2)the formative expressions of the traditional view on the universe and religion are remarkable. The Chinese embodiment and the view of the universe and religion was integrated into the patterns of dragon, water waves, clouds, fire, woods, and metals. In order to afford the creative designer capable of encompassing the East and West, the teaching about the Korean tradition along with the technical and practical aspect of fashion is most important, while encouraging the professional designer to make a sophisticated ones which are attributed to the Korean tradition, and thereby come to be attractive to the world customer. The study about the Korean costumes, traditional colors, the symbolic meaning of the traditional patterns, cuttings, compositions, extending to the various kinds of myths, songs, paintings and crafts are essential for the Korean designer brand to be the global luxury brands.

• Smart Structures and Systems
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• v.25 no.1
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• pp.97-104
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• 2020

Due to the superior properties of nanoparticles, using them has been increased in concrete production technology. In this study, the effect of zinc oxide (ZnO) nanoparticles on the mechanical and smart properties of concrete was studied. At the first, the ZnO nanoparticles are dispersed in water using shaker, magnetic stirrer and ultrasonic devices. The nanoparticles with 3.5, 0.25, 0.75, and 1.0 volume percent are added to the concrete mixture and replaced by the appropriate amount of cement to compare with the control sample without any additives. In order to study the mechanical and smart properties of the concrete, the cubic samples for determining the compressive strength and cylindrical samples for determining tensile strength with different amounts of ZnO nanoparticles are produced and tested. The most important finding of this paper is about the smartness of the concrete due to the piezoelectric properties of the ZnO nanoparticles. In other words, the concrete in this study can produce the voltage when subjected to mechanical load and vice versa it can induce the mechanical displacement when subjected to external voltage. The experimental results show that the best volume percent for ZnO nanoparticles in 28-day samples is 0.5%. In other words, adding 0.5% ZnO nanoparticles to the concrete instead of cement leads to increases of 18.70% and 3.77% in the compressive and tensile strengths, respectively. In addition, it shows the best direct and reverse piezoelectric properties. It is also worth to mention that adding 3.5% zinc oxide nanoparticles, the setting of cement is stopped in the concrete mixture.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.270-278
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• 2021

BACKGROUND: Horticultural plant growth under field and/or greenhouse conditions is affected by the climate changes (e.g., temperature, humidity, and rainfall). Therefore investigation of hydroponics on field horticultural crops is necessary for year-round production of the plants regardless of external environment changes under plant factory system with artificial light sources. METHODS AND RESULTS: Common sage (Salvia plebeia), nasturtium (Tropaeolum majus), and hooker chive (Allium hookeri) plants were hydroponically culturing in the plant factory with blue-red-white LEDs (Light-Emitting Diodes) and fluorescent lights (FLs). Leaf numbers of common sage under mixture LED and FL treatments were 134% and 98% greater, respectively than those in the greenhouse condition. In hooker chives, unfolded leaf numbers were 35% greater under the artificial lights and leaf elongation was inhibited by the conventional sunlight compared to the artificial light treatments. Absorption pattern of NO₃-N composition in hydroponic solution was not affected by the different light qualities. CONCLUSION(S): Plant factory system with different light qualities could be applied for fresh-leaf production of common sage, nasturtium, and hooker chive plants culturing under field and/or greenhouse. Controlled light qualities in the system resulted in significantly higher hydroponic growth of the plants comparing to conventional greenhouse condition in present.

• The Korea Journal of Herbology
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• v.32 no.6
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• pp.55-62
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• 2017

Objectives : This study aims to evaluate the effects of natural herb mixutre (NHM) on atopic dermatitis and skin regeneration using in vivo test. Methods : NHM was prepared with DW. 25% of NHM was applied to skin lesion, where atopic dermatitis was induced by DNCB in NC/Nga mice. The levels of cytokines (IL-4, IL-5, IL-6, IL-13, TNF-a, and $IFN-{\gamma}$), and IgE in serum were measured by Luminex. Immune cells (WBC, eosinophil, lymphocyte, and monocyte) in blood were counted by coulter counter. The gross investigation of atopic dermatitis index score test were performed during the NHM treatment period. Also, the histopathological change of dorsal skin was observed by H&E and M&T staining. Results : NHM showed the levels of IL-4, IL-5, IL-6, IL-13, IgE, WBC, eosinophil, lymphocyte, and monocyte in serum or blood were significantly decreased. On the contrary, the productions of FGF, and VEGF were increased in the serum. Also, atopic dermatitis index score in NHM-treated mice were observed in the similar levels to those of normal group. Histological examination demonstrated that NHM suppressed immune cell infiltration and thickening of epidermis, meanwhile the extraction induced collagen production in the dorsal skin. Conclusion : This study demonstrated that NHM is appeared to be effective on atopic dermatitis and skin regeneration efficacy based on the observations with hematologic, gross, and histologic examinations. Therefore, we suggest that NHM could be effectively used as an external therapeutics against atopic dermatitis and a consequence skin damage.

• Journal of the Korean Society of Costume
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• v.58 no.4
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• pp.47-57
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• 2008

Funology is a compound word with fun and technology which means the products or activity carrying fun and technology at the same time. This is one of the key words that can explain the culture of post-digital generation amongst the post-digital age. The purpose of this study was to provide the creative ideas to develop the fashion designs showing funology concept for the 21st century. As a background of funology trend, general ideas about the post-digital age and the post-digital generation were reviewed. First, funology designs among the industrial products and the funology concepts in the advertisement were examined. And the ways of expression and the meanings of funology fashion designs were extracted by analyzing funology fashion between 2000 S/S and 2008 F/W. The external expression ways of funology fashion in the post-digital age were as follows: parody of popular images, inharmony by the exaggeration or transformation, trompe l'oeil, mixture of the styles shown in the children's wear and the objects of children, patterns with childlike or animation characters, and the graffiti art. The internal meanings contained in the funology fashion were 1) fantasm showing surrealistic funology that was based on the people's pursue of fantasy free from the everyday's severe routine 2) memorism showing nostalgic funology that was based on the pursue of vanishing fear of reality and going back to the childhood. To sum up, fashions showing funology were expressed in various ways in the post-digital age. This will provide the great inspirations for creating the new coming fashions and efficient healing contents for the cold-hearted emotions of nowaday's people.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.778-791
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• 2005

A novel pneumatic artificial muscle actuator (PAM actuator), which has achieved increased popularity to provide the advantages such as high strength and high power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available and cheap power source, inherent safety and mobility assistance to humans performing tasks, has been regarded during the recent decades as an interesting alternative to hydraulic and electric actuators. However, some limitations still exist, such as the air compressibility and the lack of damping ability of the actuator bring the dynamic delay of the pressure response and cause the oscillatory motion. Then it is not easy to realize the performance of transient response of pneumatic artificial muscle manipulator (PAM manipulator) due to the changes in the external inertia load with high speed. In order to realize satisfactory control performance, a variable damper-Magneto­Rheological Brake (MRB), is equipped to the joint of the manipulator. Superb mixture of conventional PID controller and a phase plane switching control method brings us a novel controller. This proposed controller is appropriate for a kind of plants with nonlinearity, uncertainties and disturbances. The experiments were carried out in practical PAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through experiments, which had proved that the stability of the manipulator can be improved greatly in a high gain control by using MRB with phase plane switching control method and without regard for the changes of external inertia loads.