• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2535-2538
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• 2012

$SnO_2@carbon$ tube-core nanowire was synthesized via a facile self-organized method, which was in situ by one step via Chemical Vapor Deposition. The resulting composite was characterized by scanning electron microscopy, X-ray diffraction and transmission electron microscope. The diameter of the single nanowire is between 5 nm and 60 nm, while the length would be several tens to hundreds of micrometers. Then X-ray diffraction pattern shows that the composition is amorphous carbon and tin dioxide. Transmission electron microscope images indicate that the nanowire consists of two parts, the outer carbon tube and the inner tin dioxide core. Meanwhile, the possible growth mechanism of $SnO_2@carbon$ tube-core nanowire is also discussed.

• Journal of radiological science and technology
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• v.6 no.1
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• pp.81-84
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• 1983

Scattered-rays are produced from objects in x-ray diagnosis and the quality of x-ray image is influenced by presence of the scattered-ray. Therefore, constant ways and means to suppress and to eliminate the scattered-ray were devised. Authors made an experimental study on the scattered-ray content in transmitted-ray using acryl phantoms and obtained the results as follows: 1. The scattered-ray content in transmitted-ray is not influenced by filtration and tube voltage. 2. Irradiated field size and the thickness of object are a potent influence to scattered-ray content.

• Journal of the Korean Society of Radiology
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• v.4 no.3
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• pp.5-11
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• 2010

In this paper, we are suggested development of dual-mode detector for dual-energy digital radiography. Design of dual-energy radiography module for commercial BIS (Baggage Inspection System) is used in the spectrum of the X-ray generator and detector for dual-mode features and radiological characteristics were analyzed. BIS suggestl on the image detector module being used to target X-ray tube to simulate X-ray spectrum and simulated spectrum to offer through the new radiographic characteristics of the detector modules were investigated. Using X-ray experiments with an increase in the thickness of the copper filter low energy detector (LED) and high-energy detector (HED) as the difference between the output signal increases. HED, especially in the size of the output signal decreases with increasing thickness of the copper filter was found.

• Journal of radiological science and technology
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• v.17 no.1
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• pp.110-114
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• 1994

• Journal of radiological science and technology
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• v.23 no.1
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• pp.91-96
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• 2000

This work was on the reduction of exposure dose and contrast improvement by Use of Heavy Elements Filter From the result of experimental evaluation, it was found that the beam harding of X-ray was not showed in Ho and Gd, heavy elements filters, contrast to Cu and Al filters In which the harding showed. And the ratio of transit dose to surface dose and the load of X-ray tube increase in order of Al, Cu, Gd and Ho, respectively. The contrast of X-ray images using the intensifying screen and the input phosphor showed the higher value in order of Cu, Al, Gd and Ho. Therefore, in the case of using contrast media and phosphor in region of diagnostic radiology, X-ray image quality depends primarily on kVp and heavy elements filters.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.422-424
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• 2002

The accuracy of DXA(Dual Energy X-ray Absorptiometry) highly depends on the detection and separation capability of dual energy X-ray X-ray photons. In addition both of scan time and patient exposure are affected by detection efficiency. A CZT detector with a good energy resolution and high detection efficiency was evaluated for the application of bone densitometry. Its performance was compared to a photomultiplier tube with a NaI(T1) scintillator in terms of energy resolution, detection efficiency and the accuracy of bone mineral density measurement. The comparison study was performed with CZT detector and PM tube using DXA equipments(OSTEO Plus, OSTEO Prima, ISOL Technology). The energy spectrum was acquired using MCA(Multi-Channel Analyzer). The used X-ray energy ranged from 20keV to 86keV. The MCA result of the CZT detector showed a slightly sharper energy spectrum than that of NaI(T1). Detection efficiency of the CZT detector at 59.5keV was 1.4 times better. Remarkably the final results of bone mineral density measurements demonstrate only less than 1% difference. The CZT detector appears to have many benefits for the application of bone densitometry. Its excellent energy resolution can enhance the counting accuracy of dual energy X-ray spectrum. Furthermore its compactness in physical dimension and no cooling requirement will be additional benefits for a more compact and accurate bone densitometer.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.351-357
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• 2023

This Study Rreceived Subjective Evaluation ROC Evaluation from five projection. of projection. at a University Hospital to Obtain and Diagnose Sharp images of apophyseal joints and Vertral arch of Thoracic vertebrae from thoracic X-ray projection. In the Subjective evaluation, the highest Score was obtained by raising the phantom from Supine to LAO by 70° and scoring 20 points at 5° with the X-ray Tube facing the head. In addition, he scored the highest score of 19 points at 8° with the Prone Phantom standing 60° with RAO and the X-ray Tube facing the head. For Objective Evaluation, the Signal-to-noise ratio, was calculated. ROI was set at 1,564 mm2 to obtain the image signal average value (Mean value) and the Standard deviation (SD value). Objective Evaluation The signal-to-noise ratio, was the highest at 5° toward the head in the LPO 70° position of the phantom in the lying position of the Thoracic spine projection, and the Thoracic Spine was the highest at 8° toward the head of the RAO posture of 5,645.

• Journal of radiological science and technology
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• v.20 no.2
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• pp.49-55
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• 1997

This study was carried out to investigate radiographical and operating conditions of X-ray units and exposure doses to patients during chest radiography, so that the results could provide basic data used for reducing the exposure dose and for providing the diagnostic information with better quality. The conditions and exposure doses of 100 X-ray units mainly used for chest radiography were examined and also 100 radiological technologists mainly handling those apparatus at 76 medical facilities in Pusan were surveyed using a questionnaire from October 1 to December 31 in 1995. The following results were obtained from the study : 1. It was found that most units were capable of taking a high tube voltage radiography by showing 67% of the units equipped with the maximum tube voltage of 150 kV, 94% with more than 500 mA for the rating capacity and 85% with the full wave type of a signal phase. 2. For actual chest radiographical conditions, however, 80% of the units were operated at $60{\sim}100\;kVp$ and only 14% at 100 kVp and over for the high tube voltage. 3. The average exposure time was less than 0.1 second, and eighty four percent of the units adapted the X-ray tube currents ranging from 200 to 300 mA, 80% the focus-film distances between 180 and 210 cm, and 63% the focus sizes of more than 2.0 mm. 4. Most units(98%) employed additional filters made of aluminum, 75% the thickness of filters less than 2.0 mm, and only 2 units the compound filters. 5. Ortho chromatic system was only adopted in 13% of screen film system for the units, and 73% used the grid ratio at 8 : 1 for the low tube voltage during chest radiography. 6. The average exposure dose of all X-ray units during chest radiography was $371\;{\mu}Sv$ with a difference of about 16 times between the minimum to the maximum, and $386\;{\mu}Sv$ both at hospitals and at health centers, followed by $380\;{\mu}Sv$ at general hospitals and $263\;{\mu}Sv$ at university hospitals without showing any statistically significant differences. In conclusion, since patients during chest radiography at medical facilities in Pusan exposed to high levels of radiation, it is recommended that appropriate added filters and grids necessary for the high tube voltage radiography and high-speed screen systems should be adopted and used as soon as possible in order to reduce exposure dose to the patients.

• Journal of the Optical Society of Korea
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• v.11 no.2
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• pp.76-81
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• 2007

The compound refractive X-ray lens (CRL) for focusing hard X-rays is investigated to determine the parameters such as the focal length, the focal spot size, and spatial distribution at the focal spot using a simple theoretical calculations and CRLs fabricated by the self-assembly method. The number of individual compound lenses are defined for the given focal length of 1 m. The X-ray energy of 1 to 40 keV is used in the calculations. The CRL for focusing hard X-rays which generated from the X-ray tube is fabricated by nanoparticle-polymer composite in the form of circular concaves. The self-assembly method is applied to form the nanoaluminum-poly (methly meth-acrylate) composite and carbon-polymer composite CRL lenses. Aluminum nanoparticles of 100 nm and carbon microparticles are diffused in the polymer solution then the high gravity up to 6000G is applied in it to form the concave lens shape. X-ray energy at 8 keV is used for characterization of the composite CRLs. The FWHM of intensity for the fabricated nanoaluminium composite CRL system, N=10 is measured as 1.8 mm, which would give about $70{\mu}m$ in FWHM at 1 m of the focal length.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.60-65
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• 2007

The radiologic imaging device was implemented. It can be installed in an ambulance or used when an accident happens. After an equipment which generates X-ray generating unit with a tube in DC 12[V] had been made, a trait experiment using an oscilloscope was made. An experiment was carried out where the generated X-ray was saved as a form of a file using a digital detector. In this experiment, as a result of generating X-ray and detecting it using a digital detector, 1.67[MB]-, jpg- radical rays information could be saved. One distinct advantage of the developed radiologic imaging device is the fact that we can efficiently deal with emergency cases too far from the hospital, difficult to diagnose but treat simultaneously. By using the radiologic imaging device at the urgent scene of an accident or in a moving ambulance, we can provide the patient's X-ray information with the emergency medical specialist who is in the emergent medical center and have the patients prescribed and treated appropriately. As a result the developed emergency medical treatment can be expected.