• 센서학회지
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• 제21권4호
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• pp.293-297
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• 2012

CsI:Gd crystal was grown by the Bridgeman method and its scintillation properties were investigated. The wavelength peak of the luminescence spectrum for the crystal excited by X-ray was 419 nm. The range of the spectrum was from 300 nm to 800 nm. The spectrum well matched to the quantum efficiency of a typical bi-alkali photo-multiplier tube(PMT). An energy resolution of 48.2 % was obtained for 662 keV ${\gamma}$-rays of $^{137}Cs$. The three decay times were obtained as a fast(557.4 ns, 42.2 %), intermediate (1.78 ${\mu}s$, 29.7 %) and slow (5.43 ${\mu}s$, 28.1 %) components, respectively.

• 대한방사선기술학회지:방사선기술과학
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• 제21권2호
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• pp.19-25
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• 1998

By analyzing each part of expsure condition and the status of an entrance dose which is exposed to patients, this study reached the following conclusion. Since there is no standard in setting up an exposure condition, the technology practiced in each facility varies tremendously, and the entrance dose increased especially due to the improper selection of screen and grid and the shortage of a total amount of filtration in leaching the standard filtration amount. Entrance dose was, generally, turned out to be $2{\sim}3$ times as much as that of advanced countries, and there was big difference between facilities ; approximately 52 times inlateral of cervical vertebrae, 35 times in A-P of femur, 33 times in chest A-P, and 11 times in lumber A-P. Therefore, to minimize the entrance dose of a patient with thegreatest amount of image information, acquirement of technological know-how necessary for standardization of exposure condition for each part can be an important research task.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.196-199
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• 2007

The spermatozoa of Leiocassis nitidus are relatively simple cells composed of a spherical head, a short midpiece, and a tail, as in most Siluriformes. The ultrastructure is characterized by the following features: Acrosome absent, as in most teleosts; around nucleus about $1.8\;{\mu}m$ long, with a deep nuclear fossa containing the proximal and distal centrioles and mitochondria. Two centrioles approximately $180^{\circ}$ from each other; 10 or more mitochondria surrounding the axoneme (with a 9+2 microtubular pattern), arranged in two layers in the postnuclear cytoplasm and separated from the axoneme by the cytoplasmic canal. Two lateral fins on the same plane as the two central microtubules; doublets 3 and 8, which are ultrastructural characteristics of the sperma tail unlike other siluroids laking the lateral fins.

• 센서학회지
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• 제23권1호
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• pp.29-34
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• 2014

A dosimeter using tissue-equivalent scintillator by photon-counting method was developed and evaluated in its performance. The dosimeter is portable and can be operated by low power from lap-top computer. A data-acquisition software of the dosimeter system was developed by Labwindows/CVI based on Windows. The energy to channel ratio for energy calibration was 0.839 keV/ch. obtained from pulse height spectrum of $^{137}Cs$ and $^{60}Co$ gamma-ray. Using the dosimeter system, the absorbed dose of environmental radiation in Gyungju was 0.18 ${\mu}Sv/h$.

• 대한방사선기술학회지:방사선기술과학
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• 제18권1호
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• pp.55-62
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• 1995

This study was performed to find out dose distribution, pdd, surface dose and off center ratio. A few articles is analysis of dose data in radiotherapy field, there is no standardized measure of an assessment of exposure dose at diagnostic radiology, yet. And authors demonstrated a new assessment measure by ion chamber, TLD and film dosimetry system. We assurance that our data is useful to quantiative analysis of exposure dose and clinical fields for reduction of radiation dose.

• Imaging Science in Dentistry
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• 제35권4호
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• pp.225-229
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• 2005

Cleidocranial dysplasia is a rare, autosomal dominant congenital disorder. A 12-year old female visited with chief complaint of unerupted permanent teeth. Also her father showed severe class III malocclusion. The extraoral radiography and computed tomography showed delayed closure of the cranial sutures and underdevelopment of maxilla, maxillary sinuses, and frontal sinus. Both clavicles were underdeveloped and thoracic rib cage was bell­shaped. Both zygomatic process appeared as hypoplastic feature. There were many unerupted permanent and supernumerary teeth in the maxilla and mandible. We examined location and number of the unerupted teeth using 3D CT. Finally we could conclude this case was cleidocranial dysplasia based on the clinico-radiologic findings.

• 대한족부족관절학회지
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• 제10권2호
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• pp.271-273
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• 2006

In closed calcaneus fractures, the occurrence of FHL interposition in subtalar joint is relatively rare and difficult to diagnosis preoperatively. But careful physical examination and significant radiologic findings could be useful tools to diagnosis preoperatively. This findings is shearing off a superior medial fragment made up of the sustentaculum talus connected to a significant portion of the medial wall and medial aticular surface of the posterior facet.

• 대한방사선기술학회지:방사선기술과학
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• 제23권1호
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• pp.97-101
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• 2000

In this study, the highly sensitive $CaSO_4:Tm$-PTFE TLDs has been fabricated for the purpose of measurement of high energy electron. $CaSO_4:Tm$ phosphor powder was mixed with polytetrafluoroethylene(PTFE) powder and moulded in a disk type(diameter 8.5 mm. thickness $90\;mg/cm^2$) by cold pressing. The absorbed dose distribution and ranges for high energy electron were measured by using the $CaSO_4:Tm$-PTFE TLDs. The ranges determined were $R_{100}=14.5mm$, $R_{50}=24.1mm$ and $R_P=31.8mm$, respectively and the beam flatness, the variation of relative dose in 80% of the field size, was 4.5%. The fabricated $CaSO_4:Tm$-PTFE TLDs nay be utilized in radiation dosimetry for personal, absorbed dose and environmental monitoring.

• 대한안전경영과학회지
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• 제6권3호
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• pp.303-309
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• 2004

Many system devices for fluoroscopic and general X-ray studies in diagnostic radiographic system have been being changed from analog mode to digital mode. In addition, among diagnostic imaging and radiologic examinations, fluoroscopic studies that requires functional diagnosis is being widely used. The video recording method of fluoroscopic studies has been useful in functional image diagnosis and dynamic image observation, but the utility of its image quality is being reduced because of limitation in setting play segments of the video player, inconvenience of play, difficulties in preserving reproduced images, the change of image quality, etc. In order to complement these shortages, it is necessary to facilitate access to patient diagnosis information such as storing, editing and sharing functional diagnosis images in response to the trend of the digitalization of digital radiographic & fluoroscopic system(DRF). Thus this study designed and implemented a device of storing functional dynamic images real time using a computer rather than existing video recording, aiming at contribution to functional image diagnosis.

• 대한방사선기술학회지:방사선기술과학
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• 제24권2호
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• pp.29-33
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• 2001

The accurate measurement for a long bone have taken an important part in orthopedics surgical diseases when the length of extremities is different each other. However, it is true that various kinds of methods to search for the accurate measurement on used in medical centers. In this study, we measured the real length of long bone for CT Scanogram and F.F.D by 100cm and 200cm in the angle of inclination $0^{\circ},\;3^{\circ}$ and $7^{\circ}$. This method will be useful to diagnose and treat patients more accurately.