• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.773-780
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• 2003

The characteristics of soft clays is very important for the land development plan. This study is to investigate correlations between the engineering properties and the characteristics of clay minerals of the disturbed clay samples obtained from Sihwa area. This study included X-Ray Diffraction Analysis, X-Ray Fluorescence Spectrometer Analysis, Scanning Electron Microscopy Analysis and Energy Dispersive X-Ray Spectrometer Analysis. The correlations between the clay mineral properties and the laboratory and field testing results were investigated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2298-2304
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• 2012

X-ray fluorescence spectrum analysis method can be applied in many areas, including concentration analysis of RoHS elements and heavy metals etc. and we can get analysis results in a relatively short time. Because X-ray fluorescence spectrum has noises and several artifacts that lowers the accuracy of the analysis. This paper analyzes the characteristics of the noise of the X-ray fluorescence spectrum to increase the accuracy of analysis. X-ray fluorescence spectrum have the characteristics of shot noise (Poisson noise), so the noise size is relatively large in the small signal portion and the noise the size is relatively small in the large part of the signal. Existing methods of analysis and to remove noises is a method for general purposes algorithm. Since these algorithm does not reflect these noise characteristics, we get distorted analysis result. We can design efficient noise remove algorithm based on the accurate noise analysis method, and we expect high accuracy results of the elemental concentration analysis result.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.107-114
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• 2023

X-ray fluorescence analysis has been widely used in the field of science and industry because it gives information about elements and their concentrations without destruction of samples. To increase analysis accuracy of fluorescence generated by photons of the transmission-type X-ray tube for mixture and compound samples would be recommend to have strong energy near 10 keV and 20 keV simultaneously. Tungsten of 9.65 keV and molybdenum of 17.48 keV were considered as targets with dual deposition structure for obtaining two strong characteristic X-rays, and the transmission-type X-ray tube was analyzed using Geant4 Monte Carlo simulation. The W-Mo structure resulted in strong characteristic X-ray near 10 keV and 20 keV simultaneously. A structure with Mo-W multilayers of 5 ㎛ thick also gave optimal spectrum. Various material combination and thickness optimization for the dual-structured target can give X-ray spectrum with strong characteristic X-ray of specific energies.

• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.155-166
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• 2004

The characteristics of soft clays are very important for the land development plan. This study is to investigate correlations between the engineering properties and the characteristics of clay minerals of the undisturbed clay samples obtained from Sihwa area. This study included X-Ray diffraction analysis, X-Ray fluorescence spectrometer analysis, scanning electron microscopy analysis and energy dispersive X-Ray spectrometer analysis. The correlations between the clay mineral properties and the laboratory and field testing results were investigated. The characteristics of soft clay in Sihwa area were compared with those in Yangsan and Kunsan area.

• Journal of the Korean Vacuum Society
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• v.17 no.3
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• pp.247-252
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• 2008

By using the transmission anode x-ray tube developed to apply to the hand-held XRF equipment, we carried out XRF experiment and evaluated the influences of the x-ray tube on XRF spectra. XRF data, which is measured using the W-target and Rh-target tube, were good agreements with the known results. FWHM of Fe $K_{\alpha}$-line measured by W-target tube with the 35 kV-tube voltage and the $40{\mu}A$-tube current was 180 eV. This result reveals that our XRF equipment using the transmission anode x-ray tube is enough for a qualitative analysis of materials. By comparison XRF data with the integrated intensity of x-ray tube, it was confirmed that Rh-target tube is better than W-target tube for application to the hand-held XRF equipment.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.386-393
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• 2005

The calcination characteristic of waste eggshell were examined by thermal gravimetric analysis (TGA), qualitative and quantitative analysis by X-ray fluorescence, and microstructural analysis by scanning electronic microscopy(SEM). The calcined sample was lager grain and pore size.

• Journal of the Korean Society of Radiology
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• v.5 no.6
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• pp.409-413
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• 2011

An X-ray tube used an X-ray fluorescence analysis system has a low X-ray photon intensity which results in reducing measurement accuracy and increasing exposure time. These shortages can be overcame by using a monocapillary optics. A monocapillary optics was optimally designed for focusing the characteristic X-ray of tungsten (8.4 keV). The monocapillary optics can achieve a gain of 10 at the least. The monocapillary optics was fabricated by using puller and pyrex glass, raw material. In fabrication, a weigh of 45g and a temperature of $650^{\circ}$ was loaded. The total fabrication time was 460 minutes. The fabricated capillary had 87 mm in length and maximum diameter of 300 ${\mu}m$ and minimum diameter of 192 ${\mu}m$. When the fabricated monocapillary optics is applied to an X-ray fluorescence analysis system, the detection accuracy for soft elements, for example sulfur (S), will be improved.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.3
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• pp.247-254
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• 1993

A simple and direct method is developed for the determination of light Elements in atmospheric particulates by X-ray fluorescence spectrometry. Calibration standards for the light elements such as Al, Mg, K, Ca, etc are prepared by filtering real atmospheric particulates over variable time and subsequently standardizing them by Inductively Coupled Plasma-Mass Spectrometry(ICP-MS) or Atomic Absorption Spectrophotometry(AAS) analysis. The validity of this calibration method is tested by analyzing more than 100 aerosol samples, collected at urban(Seoul) and rural(Padori) sites over a two year period with this method and then comparing them with those by other accuracy proven methods such as AAS or ICP-MS: for all metals tested the results showed reasonably good agreements (R $\geq$ 0.95).

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.20-29
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• 1996

Sr0.6Ca0.4CuO2 single crystal has been synthesized by flux method and characterized by the single crystal X-ray diffraction. The compound has the orthorhombic system and the space group is Cmcm(63), lattice parameters are a=3.4645Å, b=16.1417Å, c=3.8727Å. In the (Sr1-xCax)CuO2 compound the limit of Ca from substitution for Sr was determined by the change of bond length. For this, X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDAX) and electron probe micro-analysis (EPMA) were used. From the change of Cu-O bond length as the Ca substitution, we concluded the limit of Ca incorporation Xca≒0.73.

• Analytical Science and Technology
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• v.26 no.5
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• pp.340-351
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• 2013

The chemical element and structural characterization of different types of cements and its brick stones are been investigated under forensic aspects using X-ray florescence (XRF) and X-ray diffraction (XRD) spectrometer. The XRF provides rapid compositional data for controlling almost all stages of raw materials, clinker and cement. The decisive advantage of XRD methods is based on the unique character of the diffraction patterns of crystalline substances, the ability to distinguish between elements and their oxides, and the possibility to identify chemical compounds, polymeric forms, and mixed crystals by non-destructive examination. Therefore, combination of these examinations is useful and able to apply for the forensic analysis in comparison of cements and brick stones. There are more study remained to determine the viability of method for forensic analysis of brick stones and the limits of the discrimination that can be achieved.