• Journal of Magnetics
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• v.22 no.2
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• pp.203-213
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• 2017

Magnetically suspended control & sensitive gyroscope (MSCSG) is a novel type of gyroscope with the integration of attitude control and attitude angular measurement. To improve the precision and reduce the power consumption of Lorentz Force-type Magnetic Bearing (LFMB), the air gap flux density distribution of LFMB has been studied. The uniformity of air gap flux density is defined to qualify the uniform degree of the air gap flux density distribution. Considering the consumption, the average value of flux density is defined as well. Some optimal designs and analyses of LFMB are carried out by finite element simulation. The strength of the permanent magnet is taken into consideration during the machining process. To verify the design and simulation, a high-precision instrument is employed to measure the 3-dimensional magnetic flux density of LFMB. After measurement and calculation, the uniform degree of magnetic flux density distribution reaches 0.978 and the average value of the flux density is 0.482T. Experimental results show that the optimal design is effective and some useful advice can be obtained for further research.

• Progress in Superconductivity and Cryogenics
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• v.25 no.1
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• pp.6-10
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• 2023

2 K superfluid helium cryogenic system is the crucial component of many large accelerators. When the cryogenic system is operating at 2K@3129Pa, many room-temperature parts are connected to superfluid helium via tubes. Air Leakage in these connections may lead to air contamination of the cryogenic system. Air contamination may cause equipment failure in cryogenic systems and, in extreme cases, render the entire accelerator system inoperable. Helium guard is a technique that guards against air contamination of these sub-atmospheric pressure connections in 2 K superfluid helium cryogenic system. This paper introduces a typical 2 K cryogenic distribution design for large accelerators, and make risk analysis of air contamination. Finally, the analysis of specific leakage points and detailed engineering design are presented, which may be used as a reference when designing of a 2 K superfluid helium cryogenic distribution system.

• Fashion & Textile Research Journal
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• v.16 no.2
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• pp.185-195
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• 2014

This study is to develop marine fashion items for various marine leisure activities based on the identity of Busan. Motifs from the fireworks festival and image colors of Busan are introduced for the items. A prototype design to express uniqueness and characteristics of fireworks was produced with a line combination among design modeling factors and applied to T-shirt item for comfort use in the marine leisure activity and daily life. T-shirt is one of fashion items for a message communication due to a unique modeling which can be used an excellent advertising item for the culturel identity and image of Busan. Designs were produced with the characteristics of fireworks in which circular shapes of a chrysanthemum, ring, and peony designates as motif 1, 2, 3 as well as linear shape of Niagara, fan shape, and tiger-tail as motif 4, 5, and 6. These designs were located on the front, central chest, and left chest in the T-shirts then analyzed by major students in the course of master and doctor of clothing and textiles with statistical methods. A design with new coloring preferred than the design of a symbolic construction, and circular design on the front and linear design on the left chest were preferred in the results. Prototypes were produced with peony and tiger-tail design which show a high corelation between circular and linear shape, and coloring as well as high purchasing needs. This study results will expect to use for the development of advertising items for the various events of Busan based on the textile design and fashion items with the identity of Busan.

• Fashion & Textile Research Journal
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• v.24 no.1
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• pp.1-14
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• 2022

K-pop stars are an important influence in the era of digital culture based on emotions. The purpose of this study is to visually express the identity and worldview of their music in the virtual and real world, and to promote Korea's current and past culture. The study also intends to appeal to the emotions of the global fans by designing original textile in their music video 'IDOL' on Tiny TAN - a symbol of world pop star BTS. For design development, traditional Korean images shown in the 'IDOL' video were collected, patterns for each member were selected, and a motif was designed on Adobe Illustrator. We selected the dragon as the motif for V, cloud for Suga, chrysanthemums for Jin, mask for Jung Kook, hanok pavilion for RM, fan for Jimin, and Sam Taegeuk for J-Hope. The selected motifs were designed as per the four textile design arrangement methods: square pattern, 1/2 half drop pattern, turn-around pattern, and panel pattern. The design was presented by mapping Kwaeja to Tiny TAN character. The developed textile design can be used not only for character costumes in virtual space, but also for various products such as clothes, accessories, bedding, cosmetics, stationery, and food. By using it to produce goods inspired by K-pop stars, it can be used as basic data for the development of high value-added competitive products in the global market and create synergy effects of K-Design, which would lead a new trend in the design world.

• Journal of Biosystems Engineering
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• v.31 no.3 s.116
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• pp.175-181
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• 2006

Nursery pig building is imperative to provide environmental conditions favorable to maintenance of piglet health and the efficiency of growth rate. To meet the ultimate goal, it is necessary to apply proper ventilation design and construction to a confinement livestock building. This study was conducted to investigate the performance of a modified ventilation system in terms of devised slot-inlet (modification I) and exhaust fan (modification II) to improve air change rate in a confined nursery pig building, with dimension of 5.9 m(W) ${\times}$ 12.6 m(L) ${\times}$ 2.2 m(H) in an Darby Genetic Station. The experiment was carried out in August, especially when the outdoor peak temperature were above $30^{\circ}C$ and the measured indoor environmental factors were temperature, air velocity, humidity and ammonia concentration which have been known to affect the piglet health and growth. There was no difference in indoor temperature between the original and modified ventilation systems, however the air velocity and ammonia concentration in confined nursery pig building with modified ventilation system were, in most cases, better performance than original ventilation system. Therefore, it was concluded that the slot-inlet system that kept indoor environmental factors pertinent and had an economic advantage, should be considered as a ventilation system for decreasing sensible heat from piglet in confined nursery pig building during extreme summer season.

• Korean Institute of Interior Design Journal
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• no.12
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• pp.91-99
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• 1997

Alvar Aalto has pursued National Romanticism, cultural art movement in scandinavian peninsula, organic concepts of growth and suitability, comprehensive view of nature including a possibility of coexistance of human-being and the nature well harmonized. For instance, his design expressed local features of the nature, human emotions instead of geometical arts and mathematical principles. It is noteworthy today that he built up the identity with satrical architecture vocabularies, different from modern arch-itechtural idiology. The characte-ristics of his design related to interior architecture are collectively as follows; The first, Space discontinuity of the interior and exterior, gradual process by joints which are inclined to collage with many shapes in plan and section of the space and such joints are adjusted by sensual ways and stressed with inner collectivity in his works. The second, He pursued the architectural orderfor modern irreqularity, various changes and sensual harmonies. As result, free curved line, fan shape and irregular modeling were individually expressed by technics of natural features and national characteristics of Finland. The third, Organic synthesis. A harmony through med-ums in its space, materials and space effectiveness relations are made and expressed for mixed design especially harmonized of all the materials he planned, entire harmony with total design, itemized details, materials and furnitures in entire space. The fourth, The interest of the nature based on his sense harmonized with nature made him mainly use native materials, lumbers and red bricks masonry and showed and arranged various interior sky light and grazed in to let natural light in, harmony with garden to sensually cohere to the nature and courtyard, etcetera. His major subject are to direct architectural developments through the nature and human-being in his works. At this point, it is considered that his direction of the locality and independence as a human-being made the concepts of organic space structure possible.

• Advances in aircraft and spacecraft science
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• v.6 no.6
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• pp.529-550
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• 2019

The effect of multiple process parameters on a set of continuous response variables is, especially in experimental designs, difficult and intricate to determine. Due to the complexity in aeroacoustic and vibroacoustic studies, the often-performed simple one-factor-at-a-time method turns out to be the least effective approach. In contrast, the statistical Design of Experiments is a technique used with the objective to maximize the obtained information while keeping the experimental effort at a minimum. The presented work aims at giving insights on Design of Experiments applied to aeroacoustic and vibroacoustic problems while comparing different experimental designs and approximation models. For this purpose, an experimental rig of a ducted low-pressure fan is developed that allows gathering data of both, aerodynamic and aeroacoustic nature while analysing three independent process parameters. The experimental designs used to sample the design space are a Central Composite design and a Box-Behnken design, both used to model a response surface regression, and Latin Hypercube sampling to model an Artificial Neural network. The results indicate that Latin Hypercube sampling extracts information that is more diverse and, in combination with an Artificial Neural network, outperforms the quadratic response surface regressions. It is shown that the Latin Hypercube sampling, initially developed for computer-aided experiments, can also be used as an experimental design. To further increase the benefit of the presented approach, spectral information of every experimental test point is extracted and Artificial Neural networks are chosen for modelling the spectral information since they show to be the most universal approximators.

• Journal of Aerospace System Engineering
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• v.13 no.1
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• pp.29-37
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• 2019

The objective of this study was to investigate the influence of the blade shape on the impeller performance, for design optimizing of the high airflow impeller. First, the quantity, angle, and length of blades, which are considered to have a large influence on the impeller performance, were selected as design variables. Then, 27 cases of impeller shapes were selected according to the design of experiment (DOE). To predict the conduct of the blower based on the selected impeller shape, flow analysis was performed using the immersed solid method of ANSYS CFX. In the CFD results, the highest airflow was expected in the impeller having a combination of 50 EA, $6^{\circ}$ and 5 mm. Finally, a blower with the original impeller shape and the optimized impeller shape was fabricated using a 3D printer, and the analysis tendency and experimental tendency were verified through experiments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.25-33
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• 2018

Renewable energy has been of interests in the area of modern alternative fuels. Biogas is produced in waste landfill sites through anaerobic digestion processes, including hydrolysis, acidogenesis, organic acid fermentation (acetogenesis), and methane fermentation (methanogenesis). High contents of fine dust and moisture limited its utilization for direct combustion, town gas and vehicle fuel. Thus, this study proposed a new design for a cooling device using a centrifugal cyclone for simultaneous removal of fine dust and moisture as a pretreatment in the purification processes. A heat exchanger and an ID fan, which are installed inside and outside of the cyclone, in order to cool the humid gas below the freezing point and form a foggy mist. Such an atmosphere enhanced to capture fine dust as recirculating the cold mist flow. The water removal rate was 80.8% at a relative humidity of 95%, and the particle removal efficiency was 98.3% for $2.5{\mu}m$. Simultaneous removal efficiency was 70.8% and 99.6% for particle and moisture respectively.

• Tunnel and Underground Space
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• v.27 no.1
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• pp.12-25
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• 2017

In local underground mines heavily depending on the natural ventilation, ducted fan auxiliary ventilation system is strongly recommended instead of the total mine ventilation system requiring large capital and operating costs. Optimizing the installation of ducted fans in series in long large-opening mines is required to assure the economy and efficiency of the ventilation system. The two most critical design parameters for optimization are the wall separation distance and gap length between adjoining ducts. This study aims at deriving the optimal values for those two parameters concerning the economic and environmental aspects through the extensive CFD analysis, which minimizes pressure loss, leakage and entrainment of the contaminated air in the gap space. The ranges of the wall separation distance and gap length for study are selected by taking into consideration the existing recommendations and guidelines. The ultimate goal is to optimize the auxiliary ventilation system using ducted fans in series to provide a reliable and efficient solution to maintain clean and safe workplace environment in local long underground mines.