• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.4
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• pp.141-146
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• 2020

The International Civil Aviation Organization (ICAO) developed Doc 9995 "Manual of Evidence-based Training," with the intention of providing guidance by establishing a new methodology for the development and conduct of a recurrent training and assessment program. The airline pilot training regulations were largely based on the evidence of hull losses from early generation jets, and in order to mitigate a risk, simply repeating an event in a training program was sufficient. At the time, studies concluded that it was time to change the paradigm of training and assessment program for pilots. One airline alone implemented Evidence-Based Training (EBT) program in their flight crew training and assessment program while another airline partially implemented the EBT program. In the regulatory framework of MOLIT, specific EBT regulations have not been established yet. Therefore, it is recommended to develop rules and standards that comply with ICAO SARPs as soon as possible. In this study we review the key steps in the implementation of the baseline EBT, approval process of baseline EBT program, and policy options regarding the implementation of EBT. It will provide guidance to operators, Approved Training Organizations (ATO), and stakeholders.

• Progress in Medical Physics
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• v.29 no.2
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• pp.53-58
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• 2018

This paper evaluates patient-specific quality assurance (PSQA) in the treatment of small and multiple tumors by the CyberKnife system with fixed collimators, using an ion chamber and EBT3 films. We selected 49 patients with single or multiple brain tumors, and the treatment plans include one to four targets with total volumes ranging from 0.12 cc to 3.74 cc. All PSQA deliveries were performed with a stereotactic dose verification phantom. The A16 microchamber (Standard Imaging, WI, USA) and Gafchromic EBT3 film (Ashland ISP Advanced Materials, NJ, USA) were inserted into the phantom to measure the point dose of the target and the dose distribution, respectively. The film was scanned 1 hr after irradiation by a film digitizer scanner and analyzed using RIT software (Radiological Imaging Technology, CO, USA). The acceptance criteria was <5% for the point dose measurement and >90% gamma passing rate using 3%/3 mm and relative dose difference, respectively. The point dose errors between the calculated and measured dose by the ion chamber were in the range of -17.5% to 8.03%. The mean point dose differences for 5 mm, 7.5 mm, and 10 mm fixed cone size was -11.1%, -4.1%, and -1.5%, respectively. The mean gamma passing rates for all cases was 96.1%. Although the maximum dose distribution of multiple targets was not shown in the film, gamma distribution showed that dose verification for multiple tumors can be performed. The use of the microchamber and EBT3 film made it possible to verify the dosimetric and mechanical accuracy of small and multiple targets. In particular, the correction factors should be applied to small fixed collimators less than 10 mm.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.239-246
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• 2021

Portal Dosimetry was verified using EPID to secure the clinical application and reliability of the existing research dose evaluation. The dose distribution of Geant4 was compared with the measured value by 360° rotational irradiation with a 2.5 cm cone for stereotactic brain surgery. To confirm the dose distribution of patients with brain metastasis, the dose distribution investigated by inserting a Gafchromic EBT film into the parietal phantom and the dose distribution obtained from the parietal phantom using VMAT are compared and applied to actual patients. As a result of the analysis, it was confirmed that the accuracy of the beam center and the center of the couch coincide accurately with an error within 1mm as a result of QA through a pin ball. In addition, it was confirmed that the EBT3 film has excellent linearity in the range of 0 to 10 Gy according to various dose irradiation. In the same setting as the two cervical phantoms, we confirm that the implementation and simulation results calculations of dose calculations based on Geant4 using photon beams match the experimental data within the treatment planning volume (PTV). Therefore, volume modulated arc treatment (VMAT) 360° rotational irradiation was performed, and the result of iso-dose distribution analysis by rotational irradiation confirmed that it is appropriate to include a virtual tumor.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.1
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• pp.1-9
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• 2008

Purpose: For head and neck cancer patients treated with radiation therapy, proper immobilization of intra-oral structures is crucial in reproducing treatment positions and optimizing dose distribution. We produced a man-made tongue immobilization device for each patient subjected to this study. Reproducibility of treatment positions and dose distributions at air-and-tissue interface were compared using man-made tongue immobilization devices and conventional tongue-bites. Materials and Methods: Dental alginate and putty were used in producing man-made tongue immobilization devices. In order to evaluate reproducibility of treatment positions, all patients were CT-simulated, and linac-gram was repeated 5 times with each patient in the treatment position. An acrylic phantom was devised in order to evaluate safety of man-made tongue immobilization devices. Air, water, alginate and putty were placed in the phantom and dose distributions at air-and-tissue interface were calculated using Pinnacle (version 7.6c, Phillips, USA) and measured with EBT film. Two different field sizes (3$\times$3 cm and 5$\times$5 cm) were used for comparison. Results: Evaluation of linac grams showed reproducibility of a treatment position was 4 times more accurate with man-made tongue immobilization devices compared with conventional tongue bites. Patients felt more comfortable using customized tongue immobilization devices during radiation treatment. Air-and-tissue interface dose distributions calculated using Pinnacle were 7.78% and 0.56% for 3$\times$3 cm field and 5$\times$5 cm field respectively. Dose distributions measured with EBT (international specialty products, USA) film were 36.5% and 11.8% for 3$\times$3 cm field and 5$\times$5 cm field respectively. Values from EBT film were higher. Conclusion: Using man-made tongue immobilization devices made of dental alginate and putty in treatment of head and neck cancer patients showed higher reproducibility of treatment position compared with using conventional mouth pieces. Man-made immobilization devices can help optimizing air-and-tissue interface dose distributions and compensating limited accuracy of radiotherapy planning systems in calculating air-tissue interface dose distributions.

• Progress in Medical Physics
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• v.22 no.2
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• pp.99-105
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• 2011

The purpose of this study is to evaluate the accuracy of IMRT in our clinic from based on TG119 procedure and establish action level. Five IMRT test cases were described in TG119: multi-target, head&neck, prostate, and two C-shapes (easy&hard). There were used and delivered to water-equivalent solid phantom for IMRT. Absolute dose for points in target and OAR was measured by using an ion chamber (CC13, IBA). EBT2 film was utilized to compare the measured two-dimensional dose distribution with the calculated one by treatment planning system. All collected data were analyzed using the TG119 specifications to determine the confidence limit. The mean of relative error (%) between measured and calculated value was $1.2{\pm}1.1%$ and $1.2{\pm}0.7%$ for target and OAR, respectively. The resulting confidence limits were 3.4% and 2.6%. In EBT2 film dosimetry, the average percentage of points passing the gamma criteria (3%/3 mm) was $97.7{\pm}0.8%$. Confidence limit values determined by EBT2 film analysis was 3.9%. This study has focused on IMRT commissioning and quality assurance based on TG119 guideline. It is concluded that action level were ${\pm}4%$ and ${\pm}3%$ for target and OAR and 97% for film measurement, respectively. It is expected that TG119-based procedure can be used as reference to evaluate the accuracy of IMRT for each institution.

• 한국항공운항학회:학술대회논문집
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• 2015.11a
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• pp.282-285
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• 2015

최근 항공산업은 항공 기술과 운항환경의 발달로 상당히 안전화되었으나, 인적요인(Human Factor)에 의한 사고 및 준 사고는 계속 발생하고 있다. 따라서 조종사의 훈련은 항공안전을 위한 가장 중요한 과제이나 각국의 규정에서 정하는 훈련과 실제 필요한 훈련 사이에 간격이 있어, 이를 향상하기 위해서 역량기반훈련을 기반으로 한 부조종사 자격제도(Multi-Crew Pilot License, MPL), 증거기반훈련(Evidence Based Training, EBT), 향상된 자격프로그램(Advanced Qualification Programme, AQP)이 개발되었다. 항공 선진국의 항공사들은 기존의 법정 요구량 충족위주 훈련과 항목 중심의 획일적인(One size fits all) 훈련의 패러다임을 개선하여 국제민간항공기구(International Civil Aviation Organization, ICAO)와 국제항공운송협회(International Air Transport Association, IATA)에서 제시하는 데로 개인의 역량을 더 향상 시킬 수 있는 효율적인 훈련 프로그램을 실시하여 사고 유발 인적요인을 감소시키고 있다. 역량을 중심으로 하는 조종사 훈련은 변화하는 복잡한 환경에서 예상하지 못한 위협이 발생하였을 때, 조종사들이 적절히 대처 할 수 있는 레질리언트 크루(Resilient Crew)를 양성하는 데 효과적이다.