• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.558-562
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• 1999

In this paper, the inverter spot welding system with high efficiency via an instantaneous power control is presented. In spot welding, instantaneous power control is utilized in order to attain less spatter and high welding performance. Also we proposed a PI controller for spot welder system using Evolution Strategy(ES) with varying search space. ES with varying search space which depends on fitness values at each generation is used to tune PI control parameters

• The Plant Pathology Journal
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• v.15 no.6
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• pp.348-350
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• 1999

Gray leaf spot of tomato was observed on tomato plants growing in a middle of a pepper field where pepper plants were badly infected with gray leaf spot. Both Stemphylium solani and S. lycopersici were isolated from the lesion. Both species were highly pathogenic on tomato and pepper. This is the first report in Korea of occurrence of gray leaf spot of tomato caused by Stemphylium solani Weber.

• Proceedings of the KWS Conference
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• 1997.10a
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• pp.77-80
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• 1997

Spot welding has been used in the sheet metal joining processes because of its high productivity and convenience. In this study, predicting methods of fatigue life of spot welded joint have been studied fatigue life of conch-peel spot welded joint was influenced by tail effect. Fatigue life was estimated by stress index parameter considering multiaxial stresses and tail effect. Fatigue tests were conducted with the coach-peel specimens using SPCC.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.143-148
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• 1998

A dynamic electrical parameter monitoring device was designed to simultaneously record the instantaneous value of voltage, current, power, and resistance during spot welding. The data obtained using this technique have been analyzed in term of the relationships of these parameters to the phenomena occuring during the formation(surface break-down, nugget formation and mechanical collapse) of spot weld. Finally, a database implementation is undertaken to develop techniques for improving weld quality of the resistance spot welder.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.172-174
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• 2006

Nowadays, a Spot Welding system has been widely used in all kinds of industries and the common control method of the systeme is a simple current control using SCR. But, that kind of system is less effective than a current control method using inverter. So, it is constantly proposed that an improvement of hard ware and control method of spot welding system in compliance with technological advancement in power electronics. This paper deals with spot welding system using inverter. Especially, it deals with hard ware structure, features and output characteristics.

• Restorative Dentistry and Endodontics
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• v.37 no.4
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• pp.236-239
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• 2012

Although several methods including composite resin restoration and microabrasion have been used for management of white spot lesion, tooth jewelry can be considered as another noninvasive option. This case report describes the management of white spot lesions by using tooth jewelry. This report also highlights the patients' preference for tooth jewelry as an esthetic concern.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.277-281
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• 2003

We fused RADARSAT image and SPOT panchromatic image by wavelet transform in order to improve the accuracy of classification on the water area. Fused image in water not only maintained the characteristic of SAR image (low pixel value)but also had boundary information improved. This leads to accurate method to classify water areas.

• The Plant Pathology Journal
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• v.16 no.6
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• pp.325-327
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• 2000

A leaf spot of rye (Secale cereale L.) was observed during the summer 1999 in Korea. A fungus associated with the disease was identified as Bipolaris sorokiniana (Sacc.) Shoem., based on the morphological characteristics of conidia and conidiophores. Pathogenicity of the fungus was proven by artificial inoculation on rye plants. This is the first record of leaf spot on rye caused by B. sorokiniana in Korea.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.269-271
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• 2003

A simplified analysis method is proposed in this paper, through which the deformation due to spot welding is obtained. In order to analyze the spot welding process, the finite elements are axisymmetrically modeled, and the results from them are used for analyzing the deformation of spot welded structure. It takes more little time in this simplified analysis than the analysis by 3-D continuum elements, and this analysis produces the results that nearly agree with the measured data.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.22-24
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• 1984

The mode spot size is a fundamental parameter of a single mode optical fibre which determines especially the spilces and the microbending loss. The spot-size measurement is recognised to be a useful mean to define the cut-off wavelength of single-mode fibres, ESI parameters and to predict the modal dispersion. To determine the ESI parameters, this paper is based on the use of a Ronchi ruling.