• International Journal of Concrete Structures and Materials
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• v.5 no.1
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• pp.35-42
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• 2011

In this paper, a design equation for the punching shear capacity of steel fiber reinforced concrete (SFRC) slabs is proposed based on the Japan Society of Civil Engineers (JSCE) standard specifications. Addition of steel fibers into concrete improves mechanical behavior, ductility, and fatigue strength of concrete. Previous studies have demonstrated the effectiveness of fiber reinforcement in improving the shear behavior of reinforced concrete slabs. In this study, twelve SFRC slabs using hooked-ends type steel fibers are tested with varying fiber dosage, slab thickness, steel reinforcement ratio, and compressive strength. Furthermore, test data conducted by earlier researchers are involved to verify the proposed design equation. The proposed design equation addresses the fiber pull-out strength and the critical shear perimeter changed by the fiber factor. Consequently, it is confirmed that the proposed design equation can predict the punching shear capacity of SFRC slabs with an applicable accuracy.

• International Journal of Fluid Machinery and Systems
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• v.7 no.3
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• pp.94-100
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• 2014

In double-suction centrifugal pumps, it was found that cavitation instabilities occur with vibration and a periodic chugging noise. The present study attempts to identify cavitation instabilities in the double-suction centrifugal pump by the experiment and Computational Fluid Dynamics (CFD). Cavitation instabilities in the tested pump were classified into three types of instabilities. The first one, in a range of cavitation number higher than breakdown cavitation number, is cavitation surge with a violent pressure oscillation. The second one, in a range of cavitation number higher than the cavitation number of cavitation surge, is considered to be rotating cavitation and causes the pressure oscillation due to the interaction of rotating cavitation with the impeller. Last one, in a range of cavitation number higher than the cavitation number of rotating cavitation, is considered to be a surge type instability.

• Journal of electromagnetic engineering and science
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• v.11 no.4
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• pp.290-297
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• 2011

Recent progresses in the live electrooptic imaging (LEI) technique are reviewed with emphasis on its functionality of real-time visual accesses to traveling electric waves in the GHz range. Together with the principles, configurations, and procedures for the visual observation experiments by an LEI camera system, the following results are described as examples indicating the wide application ranges of the technique; Ku-band waves on arrayed planar antennas, waves on a Gb/s-class digital circuit, W-band waves traveling both in slab-waveguide modes and aerially, backward-traveling wave along composite right/left-handed transmission line, and, waves in monolithic microwave integrated circuit module case.

• The Research Journal of the Costume Culture
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• v.20 no.3
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• pp.443-450
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• 2012

Based upon a questionnaire survey, this research study focuses on the Japanese apparel manufacturers. The aim is to understand the characteristics that make up the marketing strategys of Japanese small to medium sized apparel manufacturers. The authors generate exploratory hypotheses, which are tested via statistical analysis of data obtained from a questionnaire survey. The hypotheses tested include, the relationships between "High Value Added" strategys and factors involved with manufacturing and marketing channels. High Value Added strategys relate to the manufacturers' competitive behaviors that create high and new value for their products. The results indicate that High Value Added strategys have positive relationships for domestic outsources, the number of outsources, use of directly operated shops and the orientation for sales in overseas markets.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.137-141
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• 2004

Many monopropellant thrusters use a catalyst for decompose the propellant, hydrazine. The catalyst directly affects the thruster performances and lifetime. Therefore, it is important to confirm that the catalyst is suitable for our thrusters. Until 2002, we used She1l405 catalyst, for satellite RCS thrusters, and H-IIA and M-V launch vehicle upper-stage RCS thrusters. In 2002, however, Shell Chemical Inc. ceased manufacturing She1l405 catalyst and transferred the product to AEROJET, where it was renamed S405. We subsequently investigated the characteristics of AEROJET's S405 catalyst and SOLVAY's KC12GA catalyst, (SOLVAY is a Belgian chemical company, and KC12GA is used for ASTRIUM's thruster) and conducted thruster firing tests using the new catalysts. After conducting, we confirm that the KC12GA catalyst was suitable for our thrusters, and decided to use KC12GA for two satellite programs.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.110-113
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• 1998

It can be said that the revegetation technology in Japan was started in 1960's when Japan entered into the era of high-growth economy. In the beginning, the revegetation technology was mainly applied on the man made slopes, and with the time, the fields of the revegetation technology have been extended to the urban landscaping, ecosystem conservation, prevention of desertification and so on. With the progress of the revegetation technology and the expansion of its fields, new problems have occurred. In this paper, I introduced the history of The Japanese Society of Revegetation Technology and the present condition, and discussed about the problems of the revegetation technology in Japan.

• Journal of Crop Science and Biotechnology
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• v.11 no.3
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• pp.187-192
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• 2008

The effects of some coumarins(coumarin, 7-hydroxycoumarin, scopoletin and esculetin) were investigated on pumpkin(Cucurbita maxima Duch.) seedlings and on pumpkin glutathione S-transferases(GSTs). Coumarin and esculetin suppressed the growth of seedlings, especially the elongation of roots as well as hypocotyls. Among the compounds tested, only esculetin inhibited the activity of a particular pumpkin GST by 50%, CmGSTU3 toward 1-chloro-2, 4- dinitrobenzene(CDNB) and at a concentration of 22 ${\mu}M$. Both ethylacetae(EtOAc) and water fractions in pumpkin seedlings and different organs of one-month-old pumpkin plants contained esculetin or similar hydrophobic fluorescent substances as well as hydrophilic substances, which showed different degrees of inhibitory effects on CmGSTU3 activity.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.4
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• pp.182-190
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• 2007

Refrigeration and air-conditioning equipments are indispensable products in this civilized society. However, discharged refrigerants used in the equipments and exhausted carbon dioxide to drive the refrigeration and air-conditioning equipments are related to serious environmental problems and energy problems. Especially, the destroyed ozonosphere by the discharged refrigerants and the increased normal temperature by carbon dioxide and fluorocarbon refrigerants (green house gases) are sounded as serious global problems. For alleviating these problems, environmental-friendly refrigeration and air-conditioning equipments must be developed and will spread soon. To develop new equipment, a suitable refrigerant for each usage must be presented. In this paper, the current state of refrigerants was introduced. And, thermophysical properties of the refrigerants were introduced briefly. From the properties, the refrigerants and refrigeration cycles are promising to be used in the future, were proposed

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.967-976
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• 2021

This study aimed to investigate the mechanism by which service companies transfer their services overseas and create new value while interacting with local characteristics. A narrative analysis method was used in a case study of Ajisen Ramen, a Japanese service company that created a Japanese-style ramen restaurant, which experienced rapid growth in China. This study analyzed the restaurant as global service innovation and constructed a causal mechanism to explain the resulting rapid growth. In the pre-entry stage, the tangible value source core service facilitated its successful overseas transfer. In the post-entry stage, value source core service standardization and value sharing were interrelated and locally accepted factors. Knowledge of the local characteristics influenced the local storefront format that allowed contact with local customers. This local front format made it possible to offer local customers new value. The global service innovation mechanism developed through this study reflects a causal diagram that correlated the theoretical concepts of these events.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.10a
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• pp.477-483
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• 2001

Optimum directivity synthesis of ultrasonic transducers in linear array is considered. To realize the desired directivity, a robust and efficient method is proposed which is the direct inversion combined with the iterative DFP (Davidon-Fletcher-Powell) method. A quasi-ideal beam with the beam width and the steering beam angle specified are chosen for the numerical demonstrations. The demonstration is then extended to the case of multi-beams. The proposed combination method shows quick convergence over the single LMS or DFP method at the expense of the system matrix inversion.