• 전기의세계
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• 제13권3호
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• pp.13-20
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• 1964

The measurements of X-ray and Gamma-ray Dose Rate have been successfully made by measuring the short circuit current of the Silicon P-N Junction Diode being irradiated. The short circuit current flows when a silicon P-N Junction Diode is irradiated by X-ray of Gammaray radiations due to photovoltaic effect. A brief analysis is given in order to verify the proportionality of a short circuit current to the Dose Rate. Using this method, measurements of X-ray Dose Rate were carried out in the range of 0.05-1600 r/m successfully. The calibration was made by comparing with Victoreen condenser r-meter. Some advantages in this Dose Rate meter over a condenser r-meter were found. One can measure a continous variation of X-ray Dose Rate with this rate meter at the control console of X-ray device.

• 대한방사선기술학회지:방사선기술과학
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• 제18권1호
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• pp.71-75
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• 1995

In order to establish the photographic effects and sensitivity of various screens, fluorescence meter is used with convenience. When the radiation quality has been fixed the fluorescence has increased in proportion to X-ray dose. However, the response of fluorescence meter has the dependency of X-ray quality in accordance with KVP. as well as the difference of screen and scatter fraction can influence on the response of fluorescence meter. Using accurate fluorescence meter as a radiation detecter and as for a proper supervision the sensitive materials, we have to aware of the meter's dependency of X-ray quality and the scatter fraction.

• 대한방사선기술학회지:방사선기술과학
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• 제42권6호
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• pp.483-489
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• 2019

This paper obtained and compared these dose values by setting and comparing the X-ray imaging conditions (tube voltage 60 kVp, 70 kVp, 80 kVp, tube current 10 mAs, 16 mAs and X-ray field size are 10 × 10 cm, 15 × 15 cm). Each dose value was measure 10 times and represented as an average value. The purpose of this experiment is to serve as a reference for the X-ray exposure of diagnostic areas according to the type of dosimeter and to help with another dose measurement. The results of the experiment showed very little difference between the glass dosimeter(GD) and semiconductor dosimeter values due to changes in tube voltage of 60, 70, 80 kVp, regardless of field sized, but for dose area product(DAP), the difference in dose value was significant according to field size.

• 대한방사선기술학회지:방사선기술과학
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• 제20권2호
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• pp.28-33
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• 1997

For the Evaluation of X-ray image intensifier, we measured radiation dose at input of I. I., brightness and fluorescence at output of I. I. by using X-ray exposure meter, optometer and fluorescence meter for the relative conversion factor. Especially, by using fluorescence meter, we could easily get relative conversion factor without having regulated machine by JIS. Since using, the quality of image intensifier is going down. Consequently, it needs continuous quality maintenance.

• 한국산업보건학회지
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• 제33권4호
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• pp.439-446
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• 2023

Objectives: The aims of this study are to investigate how X-rays are emitted to surrounding parts during the ion implantation process, to analyze these emissions in relation to the properties of the ion implanter equipment, and to estimate the resulting exposure dose. Eight ion implanters equipped with high-voltage electrical systems were selected for this study. Methods: We monitored X-ray emissions at three locations outside of the ion implanters: the accelerator equipped with a high-voltage energy generator, the impurity ion source, and the beam line. We used a Personal Portable Dose Rate and Survey Meter to monitor real-time X-ray levels. The SX-2R probe, an X-ray Features probe designed for use with the Radiagem^TM meter, was also utilized to monitor lower ranges of X-ray emissions. The counts per second (CPS) measured by the meter were estimated and then converted to a radiation dose (𝜇Sv/hr) based on a validated calibration graph between CPS and μGy/hr. Results: X-rays from seven ion implanters were consistently detected in high-voltage accelerator gaps, regardless of their proximity. X-rays specifically emanated from three ion implanters situated in the ion box gap and were also found in the beam lines of two ion implanters. The intensity of these X-rays did not show a clear pattern relative to the devices' age and electric properties, and notably, it decreased as the distance from the device increased. Conclusions: In conclusion, every gap, in which three components of the ion implanter devices were divided, was found to be insufficiently shielded against X-ray emissions, even though the exposure levels were not estimated to be higher than the threshold.

• 대한방사선기술학회지:방사선기술과학
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• 제46권5호
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• pp.409-415
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• 2023

Although pediatric X-ray examinations are continuously increasing, there are not many studies on the radiation exposure to children and X-ray examination assistants according to X-ray Exposure conditions. Accordingly, we measured the radiation exposure dose of pediatric and X-ray examination assistants according to the standard guidelines and clinical average X-ray Exposure conditions when X-ray examination 10-year-old children. The effective dose and organ dose to pediatric were measured using an Dose area production meter and Monte Carlo-based PCXMC program, and the exposure dose of X-ray examination assistants was measured using an ion-chamber. When performing abdominal supine AP projection, the effective dose to children was up to 2.38 times higher under clinical average X-ray Exposure conditions than the standard guidelines. In addition, during abdominal supine AP projection, the radiation exposure dose to the X-ray examination assistants was highest on the hands at 0.0148 ~ 0.0709 mSv, and exposure dose could be reduced by up to 35% when wearing protective gloves. In conclusion, because the X-ray Exposure conditions used in clinical are unnecessarily high, unnecessary medical radiation exposure could be reduced if appropriate X-ray Exposure conditions and the radiation field area were minimized and the assistant wore shielding gloves.

• 한국방사선학회논문지
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• 제11권1호
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• pp.37-42
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• 2017

엑스선을 이용한 방사선검사에서 전리함 방식의 면적선량계를 이용하여 흡수선량과 면적선량을 측정하고, 교정계수를 측정하였다. 간접선량측정법은 엑스선발생장치의 방사부에 검출기를 설치, 측정치를 조사부위에서의 선량으로 산출하였다. 교정계수를 산출하기 위해 사용된 기기는 엑스선 발생장치로 (DK-550R/F, DongKang Medical Co. Ltd., Seoul, Korea)를 이용하였고, 교정계수를 위한 교정방법은 면적선량계와 교정선량계를 연결하고 관전압 70 kV, 관전류 500 mA, 0.158 sec로 79 mAs 조건을 이용하였다. 면적선량계 (PD-8100, Toreck Co. Ltd. Japan)을 이용하였고, 기준선량계는 반도체검출기 (DOSIMAX plus A, Scanditronix, $Wellh{\ddot{o}}fer$, Germany)를 이용하였다. 면적선량계를 전리함의 다중조리개 전면에 설치 후 정확한 선량 측정을 위해 기준선량계를 이용하여 선량계의 교정계수를 구하였다. 실험적으로 노출하여 측정된 값과 교정선량계에서 나온 값에 각각의 교정계수를 곱하여 산출하였다. 교정계수는 1.045로 산출되었다. 전리함 방식의 면적선량계에서 관전압에 따른 교정계수를 산출하기 위해 흡수선량과 면적선량을 구하여 교정상수를 산출하였다. 면적선량계의 교정계수를 구하여 정확한 면적선량을 산출하여야 한다.

• 대한디지털의료영상학회논문지
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• 제11권1호
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• pp.5-13
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• 2009

There are several reasons to take X-ray in case of inpatients. Some of them who cannot ambulate or have any risk if move are taken portable X-ray at their wards. Usually, in this case, many other people-patients unneeded X-ray test, family, hospital workers etc-are indirectly exposed to X-ray by scatter ray. For that reason I try to be aware of free space scatter dose accurately and make the point at issue of portable X-ray better in this study. kVp dose meter is used for efficiency management of portable X-ray equipment. Mobile X-ray equipment, ionization chamber, electrometer, solid water phantom are used for measuring of free space scatter dose. First of all the same surroundings condition is made as taken real portable X-ray, inquired amount of X-ray both chest AP and abdomen AP most frequently examined and measured scatter ray distribution of two tests individually changing distance. In the result of measuring horizontal distribution with condition of chest AP it is found that the mAs is decreased as law of distance reverse square but no showed mAs change according to direction. Vertical distribution showed the mAs slightly higher than horizontal distribution but it isnt found out statistical characteristic. In abdomen AP, compare with chest AP, free space scatter dose is as higher as five-hundred times and horizontal, vertical distribution are quite similar to chest AP in result. In portable X-ray test, in order to reduce the secondary exposure by free space scatter dose first, cut down unnecessary portable order the second, set up the specific area at individual ward for the test the third, when moving to a ward for the X-ray test prepare a portable shielding screen. The last, expose about 2m apart from patients if unable to do above three ways.

• Nuclear Engineering and Technology
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• 제56권6호
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• pp.2190-2194
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• 2024

The study investigates the dose-dependent direct X-ray sensing characteristics of Brucinium benzilate (BB) and N-acetylglycine (NAG) organic crystals. BB and NAG were prepared as a slurry and deposited as a thick film on a patterned metal electrode. The X-ray induced photocurrent response was examined for various exposure doses using an intraoral pulsed 70 keV X-ray machine connected to a source meter. Subsequently, the morphological properties and thickness of the thick films were analyzed using scanning electron microscopy (SEM). At a photon energy of 70 keV, the attenuation coefficient values for NAG and BB crystals were determined to be approximately 0.181 and 0.178 cm²/g, respectively. The X-ray stopping power of the crystals was measured using a suniray-2 X-ray imaging system. To evaluate the responsiveness of the sensors, the photocurrent sensitivity and noise equivalent dose rate (NED) were calculated for both thick films. The findings demonstrated a noteworthy capability of sensing low doses (mGy), thereby suggesting the potential application of these organic materials in X-ray sensor development.

• Imaging Science in Dentistry
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• 제37권2호
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• pp.65-68
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• 2007

Purpose: To compare the leakage and scattered radiation from hand-held dental X-ray unit with radiation from fixed dental X-ray unit. Materials and Methods: For evaluation we used one hand-held dental X-ray unit and Oramatic 558 (Trophy Radiologie, France), a fixed dental X-ray unit. Doses were measured with Unfors Multi-O-Meter 512L at the right and left hand levels of X-ray tube head part for the scattered and leakage radiation when human skull DXTTR III was exposed to both dental X-ray units. And for the leakage radiation only, doses were measured at the immediately right, left, superior and posterior side of the tube head part when air was exposed. Exposure parameters of handheld dental X-ray unit were 70 kVp, 3 mA, 0.1 second, and of fixed X-ray unit 70 kVp, 8 mA, 0.45 second. Results: The mean dose at the hand level when human skull DXTTR III was exposed with portable X-ray unit $6.39{\mu}Gy$, and the mean dose with fixed X-ray unit $3.03{\mu}Gy$ (p<0.001). The mean dose at the immediate side of the tube head part when air was exposed with portable X-ray unit was $2.97{\mu}Gy$ and with fixed X-ray unit the mean dose was $0.68{\mu}Gy$ (p<0.01). Conclusions: The leakage and scattered radiation from hand-held dental radiography was greater than from fixed dental radiography.