• Structural Engineering and Mechanics
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• v.20 no.6
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• pp.727-745
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• 2005

The present study is an experimental investigation into the behaviour of high strength concrete square short columns subjected to biaxial bending moments and strengthened by GFRP laminates. The main objectives of the study are: to evaluate the improvement in the structural performance of HSC short square columns subjected to small biaxial eccentricity when strengthened by externally applied FRP laminates, and to investigate the optimum arrangement and amount of FRP laminates to achieve potential enhancement in structural performance especially ductility. The parameters considered in this study are: number of FRP layers and arrangement of wraps. The load eccentricity is kept corresponding to e/t = 0.125 in two perpendicular directions to the columns principal axes, and the wraps are applied in single or double layers (partial or full wrapping). In the present work, test results of five full scale concrete columns are presented and discussed. The study has shown that FRP wraps can be used successfully to enhance the ductility of HSC columns subjected to biaxial bending by 300%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.219-219
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• 2009

ceramic metal halide lamps are a subset of high intensity discharge lamps so named because of their high radiance These lamps weak ionized plasma in a fire-resisting but light transmissive wrapping by the corridor of current through atomic and molecular vapors. for commercial applications, For commercial applications, the conversion of electric power to light must occur with good efficiency and with sufficient spectral content throughout the visible (380-800 nm) to permit the light so generated to render colors comparable to natural sunlight. the purpose of this paper is to carry out a study on the variation of ageing time(2000 On/Off[hr]) on the performance of 150W CMH lamps. Experimental results show that the blackening by reacting W(tungsten)with I atomic has been created in the arc tube of an ageing lamp(2000 On/Off[hr]), the arc was unstable, and increased a lamp resistance made lamp voltage increases significantly. Also, Color temperature of the ageing lamp was moved by the losses of Ho with Dy atomics and by recombination of Na with I.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.5
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• pp.69-77
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• 2004

FRP rebar has low bond performance than steel rebar. Usually, FRP rebar has about 60% of bond strength of steel rebar. Without adequate bond to concrete, the full composite action between reinforcement and concrete matrix can not be achieved. Therefore, FRP rebars must also have surface deformations that provide good bond to concrete. The purpose of this research was decided an optimum surface deformation patterns through bond test of FRP rebar. Eighteen surface deformation patterns of FRP rebar with widely different geometries were investigated. Based on the test results, we established optimum surfale deformation pattern. Bond tests were performed for three types of surface deformation patterns of FRP rebar including sand coated rebar, ribbed rebar, and wrapped and sand coated rebar that commercially available, and two types of FRP rebar including CFRP, GFRP rebars that optimum surface deformation pattern is applied. According to bond test results, FRP rebars that optimum surface deformation pattern is applied were found to have better bond strength with concrete than currently using FRP rebar.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.11-16
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• 2005

The round bale wrappers are generally used for rice straw after the harvesting of low land rice by combine harvester. In this situation, the bale wrappers should be well adapted under the travelling over raised borders and temporary ditches in soft soil of narrow rice fields. The study was conducted to improve the performance of bale wrapper through the new design for compact size, lowered gravity center and lowered power consumption. The prototype of round bale wrapper had been designed and assembled to tractor with three point hitch mounted. The machine type is one roll driving system with one roll for rotating and one roll for wrapping. The driving torque and work performance of the machines were measured and analysed. The torque requirement of the prototype and conventional type was 6kgf-m and 12kgf-m, respectively. The prototype shaved less friction resistance between bale driving roll and round bale. and the power requirement can also be reduced from 12kgf-m in the conventional to 6kgf-m in the prototype. The work efficiency of the new bale wrapper was $45\%$ higher than the conventional wrapper, and the working cost of the prototype can be reduced $17\%$ than that of the conventional.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.161-169
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• 2016

Purpose: To improve the insufficient mechanized forage harvesting system, an integrated forage harvester that produces midsize round bales was developed. Methods: The harvesting performance of the developed harvester was tested in a forage plantation. The harvesting performance was evaluated by investigating the bale production performance and residue ratios of the harvester at three levels of tractor driving speeds. Results: The bales outputs per hour by driving speed shown by the harvester were 30 bales (6.8 MT) at 2.3 km/h, 36 bales (8.4 MT) at 3.2 km/h, and 44 bales (10.5 MT) at 5.1 km/h in the case of rye-straw. In the case of rice-straw, they were 43 bales (8.8 MT) at 4.3 km/h, 44 bales (9.7 MT) at 5.0 km/h, and 48 bales (10.7 MT) at 6.2 km/h. In the case of Italian ryegrass (IRG), they were 35 bales (10.7 MT) at 7.0 km/h, 37 bales (12.0 MT) at 8.3 km/h, and 38 bales (13.2 MT) at 9.5 km/h. The average ratios of residues to the available quantities were 2.61% in the case of rye-straw, 1.89% in the case of rice-straw, and 1.57% in the case of IRG. When residues smaller than 200 mm, which cannot be collected, were excluded, the residue ratios of all crops were good, as they did not exceed 1.0%. Conclusions: Since the baling and wrapping functions, which had been separately operated, were integrated into the developed harvester, the developed harvester is expected to maximize bale production efficiency and increase labor productivity, thereby increasing farming profitability.

• Earthquakes and Structures
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• v.10 no.2
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• pp.313-328
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• 2016

Beam-column joints are recognized as one of the most critical and vulnerable zones of a Reinforced Concrete (RC) moment resisting structure subjected to seismic loads. The performance of the deficient beam-column joints can be improved by retrofitting these joints by jacketing them with varied materials like concrete, steel, FRP and ferrocement. In the present study strength behavior of RCC exterior beam-column joints, initially loaded to a prefixed percentage of the ultimate load, and retrofitted using ferrocement jacketing using two different wrapping schemes has been studied and presented. In retrofitting scheme, RS-I, wire mesh is provided in L shape at top and at bottom of the beam-column joint, whereas, in scheme RS-II along with wire mesh in L shape at top and bottom wire mesh is also provided diagonally to the joint. The results of these retrofitted beam-column joints have been compared with those of the controlled joint specimens. The results show an improvement in the ultimate load carrying capacity and yield load of the retrofitted specimens. However, no improvement in the ductility and energy absorption has been observed.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.834-839
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• 2001

Calandria tube wrapping each pressure tube is one of the key structural components of CANDU reactor(Calandria) which is consisted of many pressure tubes containing nuclear fuel assemblies. As the Calandria tube(made of zirconium alloy) is sagging due to its thermal and irradiation creep during the plant operation, it possibly contacts with liquid injection nozzle crossing beneath the Calandria tube, which subsequently results in difficulties on the safe operation. It is therefore necessary to check the gap for the confirmation of no contacts between the two tubes, Calandria tube and liquid injection tube, with a proper measure during the life of plant. In this study, an ultrasonic measurement method was selected among several methods investigated. The ultrasonic device being developed for the measurement of the gap was introduced and its preliminary performance test results were presented here. The gap between LIN and CT at site was measured using by this ultrasonic device at site.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.1
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• pp.181-188
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• 2001

The evaluation of the noise for the an existing engine was carried out to improve the current noise level. The applied techniques were 1m air-borne noise, combustion noise analysis, torsional analysis at the front pulley and sound pressure intensity. In addition, the evaluation of the possibility to the noise reduction by means of wrapping the parts was performed to propose the detailed information in engine design. In view of the obtained results, the following countermeasures were recommended to reduce the current noise level through the above methods. Furthermore, in order to assess the influence of combustion noise on the overall engine noise, the noise test was also performed by the change of intake air temperature up to 5$0^{\circ}C$ in steps of 1$0^{\circ}C$. Finally, the fixed design specifications to reduce the engine noise will be decided in consideration of the test data for proto type engine.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.1
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• pp.167-174
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• 2010

This paper aims to examine the status of sizing specifications for disposable sanitary pads on the market and to offer information on product design that reflect the requests of consumer by gathering opinion through the practical experience of consumers. Seventy-six varieties of sanitary pads on market are measured and the evaluations of wearing comfort were investigated by the questionnaire and interview for sixty three varieties of sanitary pads. As a result, they were classified into five sizes related with length but vaguely related with thickness and width. Thickness is distinguished by the compressibility that is marked as slim or ultra slim by the same brand. However, there is no sizing consistency for all products. The result shows that there is some confusion for consumers to choose desired sizes, In addition, the perception of wearing is categorized into four factors that are product performance, size and fit, wearing feeling and margin of action, and adhesive property and wrapping. The manufacturing specifications for the sanitary pads on domestic market, the requests of consumers for sanitary pad design modifications, and proposals for follow-up studies were figured out through this research.

• Computers and Concrete
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• v.8 no.5
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• pp.597-616
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• 2011

With respect to rehabilitation, strengthening and retrofitting of existing and deteriorated columns in buildings and bridges, CFRP sheets have been found effective in enhancing the performance of existing RC columns by wrapping and bonding CFRP sheets externally around the concrete. Concrete columns and piers that are confined by both lateral steel reinforcement and CFRP are sometimes referred to as "hybrid" concrete columns. With the availability of experimental data on concrete columns confined by steel reinforcement and/or CFRP, the study presents modeling using artificial neural networks (ANNs) to predict the compressive strength of hybrid circular RC columns. The prediction of the ultimate confined compressive strength of RC columns is very important especially when this value is used in estimating the capacity of structures. The present ANN model used as parameters for the confining materials the lateral steel ratio (${\rho}_s$) and the FRP volumetric ratio (${\rho}_{FRP}$). The model gave good predictions for three types of confined columns: (a) columns confined with steel reinforcement only, (b) CFRP confined columns, and (c) hybrid columns confined by both steel and CFRP. The model may be used for predicting the compressive strength of existing circular RC columns confined with steel only that will be strengthened or retrofitted using CFRP.