• Journal of Aerospace System Engineering
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• v.9 no.3
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• pp.1-7
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• 2015

In this study, the design of compound smart materials hydraulic pump that can be applied to a small-medium size UAV having a limited space envelope and weight has been conducted. Compound Smart Material Pump(CSMP) proposed in this paper is composed of a pressurize pump and a flow pump for supplying the high pressure and fluid displacement to overcome the disadvantages of the piezoelectric actuator which has a small strain. Though this compound smart material pump has been designed as small size and lightweight as possible, it can sequentially supply the sufficient large flow rate and pressure required for the brake operation. For the design of CSMP, about 2,700 kg (6,000 lb) class fixed wing manned aircraft was selected. Based on the established requirements, the design of the CSMP have been done by strength, vibration, and fluid flow analysis.

• The Journal of Economics, Marketing and Management
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• v.10 no.2
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• pp.1-13
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• 2022

Purpose: The findings are expected to be used as basic data for policy establishment for systematic support and upbringing of small and medium-sized suppliers through the current status and characteristics of the industrial structure of the MRO consumable materials industry as a whole and the market trend. Research design, data, and methodology: This survey is conducted in 2019 mainly for companies that operate consumable materials delivery business, and the survey size is about 25,000 in advance (selected) and about 2,000 in the main survey. Using cluster analysis and multidimensional scaling, we derive the visualization of the homogeneous grouping of cases and the relationship structure between them. Results: Based on the attributes of reason for not having an online trading system, it is classified into three and four clusters for industry and company size, respectively, and the feature and pattern of each individual can be are relatively evaluated and visualized. Conclusions: Small and medium-sized consumable material suppliers specialize in products rather than fierce pricing strategies or external expansion strategies and it is more effective to establish a plan to promote the growth of both large and small enterprises through cooperation with large corporations.

• Journal of the Semiconductor & Display Technology
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• v.21 no.3
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• pp.125-129
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• 2022

The current display technology tends to be highly integrated with high resolution, the element size is gradually downsized, and the structure becomes complicated. Inductively coupled plasma (ICP) dry etcher of various types of etching equipment is a structure that places a large multi-divisional antenna source on the top lid, passes current to the Antenna, and generates plasma using the induced magnetic field generated at this time. However, in the case of a device of a large area size, a support that can withstand a load structurally is necessary, and when these support portions are applied, arrangement of antenna becomes difficult, which causes reduction in uniformity. As described above, the development of antenna source of a large area having a uniform plasma density on the whole surface is difficult to restrict hardware (H/W). As a solution to this problem, we confirmed the change in uniformity of plasma by applying two kinds of specific shape faraday shield(FICP) to the lower part of the large area upper lid antenna of 6 and 8th more than that generation size. In this thesis, we verify the faraday shield effect which can improve plasma uniformity control of ICP dry etcher equipment applied to medium and large displays.

• Korean Journal of Rural Living Science
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• v.5 no.2
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• pp.117-123
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• 1994

The purpose of this study was to establish the range of the body frame size determination for elderly subjects. Anthropometric data were collected from over 60 years old 229 elderly peoples. Three methods for determining frame size were to measure elbow breadth, ankle breadth, and height to wrist circumference ratio. Among the three variables, ankle breadth exhibited the lowest correlation with skinfold thickness and changed little with age. A pairwise comparision among three methods for determining frame size showed that the highest incidence of overall agreement was achieved when the ankle breadth and elbow breadth were compared. This analysis supported that ankle breadth can be used as an indicator of frame size. Small, medium and large categories of ankle breadth were presented depending on whether the measurements were below the 15th, between the 15th and 85th, and above the 85th percentile for ankle breadth.

• Management & Information Systems Review
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• v.22
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• pp.1-23
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• 2007

This paper investigates the relationships between exports, firm size, and firm dynamics. It is based on a longitudinal data covering listed firms in the Korean manufacturing industry. We found the stylized fact that the probability that a firm is exporter increases with firm size. A regression model for the determinant of export/sales ratio including dynamic adjustment process is tested on a cross-section sample for the year 2001. Empirical findings suggest that there is a positive and inversely U-shaped relationship between firm size and export/sales ratio, just for basic material and capital good industry. Except for firm size, the hypotheses concerning human capital intensity, physical capital intensity, R&D intensity, and patent are rejected. Using Granger causality test, we found that the rate of growth of total sales influences the change of the export/sales ratio with time lag for medium-sized firms. Finally, some policy implications are presented.

• KSBB Journal
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• v.13 no.4
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• pp.438-443
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• 1998

Effects of various environmental factors on cell size index(FCW/DCW) in Thalictrum rugosum. Lithospermum erythrorhizon and Taxus cuspidata plant cell suspension cultures were investigated. Time course change of cell size index were also observed. In batch cultures, FCW/DCW increased according to the decrease of sugar concentration. For short-term experiment within 24 hr, FCW/DCW value could be reduced significantly by increasing sugar concentration. When an osmoticum such as mannitol was added, FCW/DCW converged to a low value. Therefore, it was confirmed that osmolality of the medium was important in determining cell size or water content of the cells. Inorganic salts or treatment with organic solvent also exhibited some effect on the cell size index. However, pH and centrifugal force did not show any influences. On the other hand, it was found that the addition of Pluronic F-68 reduced FCW/DCW. By combining these results effectively, it may be possible to increase the cell concentration in high density culture to a higher extent.

• Preventive Nutrition and Food Science
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• v.15 no.1
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• pp.67-73
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• 2010

The effects of particle sizes (small, medium and large sizes) and gelatinization treatment on the changes of the instant properties of Job's tears powder were investigated. The degree of gelatinization on the different particle size samples of Job's tears powder was the highest in the small particle size, and it also showed an increasing trend regardless of pregelatinizing whether it is or not as the particle size decreased from large particle size to small particle size. The water solubility index of the pregelatinized samples was high compared to that of ungelatinized samples regardless of particle size and temperatures. The water absorption and swelling power increased as particle size and temperature were increased. The dispersibility and sinkability of ungelatinized sample was increased as particle size and temperature were increased and it also showed lower value regardless of particle size and temperature. However, the dispersibility and sinkability of pregelatinized samples were shown to have the opposite result, such that the smallest particle size of pregelatinized sample had the lowest sinkability (11.3%). The turbidity of the pregelatinized small particle size was the highest by a factor of 1.08.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.22-28
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• 2006

Computer simulation of the air flow over an automotive vehicle is now becoming a routine process in automotive industry to assess the aerodynamic characteristics of a medium-size vehicle such as $C_d\;and\;C_1$ and aslo to investigate the possibility of improving aerodynamic performance of the vehicle as a preliminary design for the production line. Mainly due to its contribution in saving time and cost in the development of new cars, computer simulation of the air flow over a vehicle is usually done well before a production car is introduced to the market and in gaining more and more attention as powerful computer resources are getting readily available nowadays. To aerodynamically design a car is mainly related with reducing a drag coefficient of car. A well designed car usually has a $C_d$ value in the range of $0.3{\sim}0.4$. It is understandable that automotive industry is rushing to reduce a drag coefficient as reducing even a small fraction of the $C_d$ value can have an enormous overall impact on many areas. Actually, the present research model was able to achieve a $C_d$ value in the range of $0.3{\sim}0.36$ for flow velocities of $60km/h{\sim}100km/h$ by strategically removing the possible factor hazardous to lower $C_d$ value. Prediction of the medium-size vehicle aerodynamics using CFD was performed when an actual car model was in the development stage and three-dimensional modeling was also performed to optimize it as the best model in terms of the best aerodynamic performance.

• Journal of the Korean Society for Library and Information Science
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• v.36 no.4
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• pp.147-155
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• 2002

The purpose of this study is to identify an acquisition material duplication rate among three academic libraries for developing an academic library network. Three academic libraries located in Gyonggi-do, Korea were selected for data collection. The acquisition lists in both 2000 and 2001 were compared and analyzed between two libraries respectively. The results show that the duplication rate is 0.4% in 2000 and 2.8% in 2001 between medium in libraries, and 1.33%, 1.11% in 2000 and 3.63%, 3.88% in 2001 between a big size library and medium size libraries. These tell us that a big library can get benefit from a library network with medium size libraries.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.55-61
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• 2016

BIM is a rising core technology for increasing the productivity of the AEC industry, but such a paradigm shift is placing excessive demand on the practice of small medium size enterprises. BIM has many useful functions that are difficult to imagine in 2D CAD but BIM programs and the system buildup cost are too expensive. Therefore, small medium size enterprises hesitate to apply BIM in their fields. In this study, a customized 4D and 5D system was implemented using the building information generated from basic BIM tools, such as Revit, MS Project, Navisworks, and Excel VBA's customizing process to review the schedule and verify the quantities according to the schedule. Those programs are so basic in BIM circumstances, that small medium size enterprises can be equipped without burden. As a result, essential building information for 4D and 5D system implementation was investigated and its customizing process was established.