• The Journal of Information Systems
• /
• v.12 no.1
• /
• pp.159-175
• /
• 2003

During the early stage of radioactive disposal programs, important issues related with quality assurance of data sets, methodologies, R&D procedures are recognized as important ones. This paper focused on the development of web-based workflow standards for the QA procedures of the radioactive waste disposal programs. The flow of process was analyzed based on workflow concepts proposed by the Workflow Management Coalition (WfMC). QA system is based on the principles of T2R3. T2R3 Workflow was used to standardize and restructure the business and/or work process in the industry or organization. The WfMC has identified five functional interfaces to a workflow service as part of its standardization program. They are composed of process definition interface, worklist handler, application program interface, interface between workflows, and system management. The task flow and QA program were defined based on the workflow ideas. QA procedures for the R&D results of radiation disoposal were analyzed following the reference model of workflow. In addition, six program run list were created and implemented. The creation, revision, and approval of the test data were designed to be inplemented on the web environment. Through this system, R&D procedures such as planning, research, documentation, internal review and future independent peer review processes could be well organized and stored more systematically on the database and knowledge base. This will encourage the usage and data sharing between interested parties through it's clear and transparent workflow standards.

• Progress in Medical Physics
• /
• v.28 no.3
• /
• pp.111-121
• /
• 2017

Verification of dose distribution is an essential part of ensuring the treatment planning system's (TPS) calculated dose will achieve the desired outcome in radiation therapy. Each measurement have uncertainty associated with it. It is desirable to reduce the measurement uncertainty. A best approach is to reduce the uncertainty associated with each step of the process to keep the total uncertainty under acceptable limits. Point dose patient specific quality assurance (QA) is recommended by American Association of Medical Physicists (AAPM) and European Society for Radiotherapy and Oncology (ESTRO) for all the complex radiation therapy treatment techniques. Relative and absolute point dose measurement methods are used to verify the TPS computed dose. Relative and absolute point dose measurement techniques have a number of steps to measure the point dose which includes chamber cross calibration, electrometer reading, chamber calibration coefficient, beam quality correction factor, reference conditions, influences quantities, machine stability, nominal calibration factor (for relative method) and absolute dose calibration of machine. Keeping these parameters in mind, the estimated relative percentage uncertainty associated with the absolute point dose measurement is 2.1% (k=1). On the other hand, the relative percentage uncertainty associated with the relative point dose verification method is estimated to 1.0% (k=1). To compare both point dose measurement methods, 13 head and neck (H&N) IMRT patients were selected. A point dose for each patient was measured with both methods. The average percentage difference between TPS computed dose and measured absolute relative point dose was 1.4% and 1% respectively. The results of this comparative study show that while choosing the relative or absolute point dose measurement technique, both techniques can produce similar results for H&N IMRT treatment plans. There is no statistically significant difference between both point dose verification methods based upon the t-test for comparing two means.

• The Journal of KAIRB
• /
• v.6 no.2
• /
• pp.48-55
• /
• 2024

Purpose: The purpose of this study is to introduce the Institutional Review Board (IRB) member-based internal audit method performed at A University Hospital, a secondary medical institution, and to identify the differences in audit results according to the characteristics of each auditor and the factors affecting the internal audit results. Furthermore, we will find out what needs to be improved in the internal audits to achieve Quality assurance (QA) objectives for human subject research conducted in medical institutions. Methods: The auditors were divided into group A (IRB member belonging to institution A) and group B (clinical trial QA administrator belonging to other institutions) and independently inspected the 2 studies using the same internal audit checklist (consisting of 11 domains, 130 items), and the differences in the internal inspection checklists written by each auditor were compared and analyzed. Results: In the case of audit for the study 1, the number of missing checklists is 1 for group A and 0 for group B, and the number of the matters to be pointed out is 1 for group A and 12 for group B. In the case of audit for the study 2, the number of missing checklists is 2 for both A and B, and the number of points is 5 for A and 4 for B. The differences in the internal audit results written by each auditor that the authors verified are summarized as follows. First, there were more comments from group B auditor than from group A auditor. Second, the results may vary because each auditor has different criteria for evaluating the appropriateness of an item. Third, there are cases where the questions on the checklist are vague or the definition is not clear, so they have the same opinion but check it with different answers. Fourth, if the auditors make a mistake when filling out the checklist, it causes to led to different the results. Conclusion: We propose the following items that should be improved in order to conduct consistent and efficient internal audits. First, it is necessary to test the tool in order to carry out reliable and consistent internal audits. Second, it is necessary to complete specialized training related to internal audit before conducting internal audit. Third, before notifying the audit results, it is necessary to have a procedure or a final review system to check whether the audit contents are appropriate. Fourth, Institutional support is needed to recruit specialized personnel for internal audits.

• Progress in Medical Physics
• /
• v.14 no.1
• /
• pp.20-27
• /
• 2003

For the treatment of cancer using computer controlled linear accelerator, it is important to ensure that all equipments are operated properly. Therefore, many studies were performed and published on the safe use of radiotherapy machine controlled by computer logic and microprocessor These studies provided methods of preventing accident from software and hardware failure. In Korea, the use of computer controlled linear accelerator has increased over the past 10 years. However, there are no standard protocols for quality assurance (QA) of linear accelerator. In this study, three QA protocols from America, Japan, and Europe were collected and summarized. In addition, agreement and disagreement among the protocols were analyzed. In conclusion, the QA items included in the protocols were similar among the various QA protocols although there were differences in performance frequencies.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.43 no.6 s.312
• /
• pp.68-75
• /
• 2006

During cancer therapy by using high energy radiation, it is possible to improve the radiation therapy efficiency by performing a precise radiation therapy after verification of generated setup errors. In this paper, the video based electronic portal imaging device (EPID) which could display the portal image with near real time was developed to verify treatment position errors in radiation therapy instead of an analog typed portal film. This EPID system for applying QA tool of radiation therapy machine was consisted of a metal/fluorescent screen, $45^{\circ}$mirror, camera and image grabber. Radiation field verification has been performed to check quality assurance of the treatment machine itself by using this EPID system. The radiation field error was easily observed by edge detection of irradiated field size on EPID image when $0.6^{\circ}$ shift of collimator angle was generated. So, this implemented EPID system could be used as a radiation QA tool.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2021.07a
• /
• pp.575-576
• /
• 2021

프로토타이핑은 게임의 방향성을 정하고 향후 완성된 게임의 모습을 예상케 해 제작 프로세스를 줄이고 제작 비용을 최소화 시키는 가장 효과적인 방법이다. 본 연구에서는 게임 제작 프로젝트에서 프로토타입을 개발 방법론을 기본으로 하여 게임기획, 게임 QA, 게임 사용자의 피드백을 파이프라인으로 연결하여 게임성을 향상 시키는 개발 방법에 대하여 살펴본다. 게임 개발에 있어 위 3가지 단계는 게임을 개발하는데 있어 게임성을 확보하기 위한 효율적인 방법임을 확인한다.

• Radiation Oncology Journal
• /
• v.33 no.1
• /
• pp.42-49
• /
• 2015

Purpose: In order to keep the acceptable level of the radiation oncology linear accelerators, it is necessary to apply a reliable quality assurance (QA) program. Materials and Methods: The QA protocols, published by authoritative organizations, such as the American Association of Physicists in Medicine (AAPM), determine the quality control (QC) tests which should be performed on the medical linear accelerators and the threshold levels for each test. The purpose of this study is to increase the accuracy and precision of the selected QC tests in order to increase the quality of treatment and also increase the speed of the tests to convince the crowded centers to start a reliable QA program. A new method has been developed for two of the QC tests; optical distance indicator (ODI) QC test as a daily test and gantry angle QC test as a monthly test. This method uses an image processing approach utilizing the snapshots taken by the CCD camera to measure the source to surface distance (SSD) and gantry angle. Results: The new method of ODI QC test has an accuracy of 99.95% with a standard deviation of 0.061 cm and the new method for gantry angle QC has a precision of $0.43^{\circ}$. The automated proposed method which is used for both ODI and gantry angle QC tests, contains highly accurate and precise results which are objective and the human-caused errors have no effect on the results. Conclusion: The results show that they are in the acceptable range for both of the QC tests, according to AAPM task group 142.

• Journal of Aerospace System Engineering
• /
• v.2 no.3
• /
• pp.7-11
• /
• 2008

This is a study to research the effective way to enhance the performance of safety management by gathering and analyzing the information of undesirable occurrences that may result in accident or serious incident. This includes the way to identify the potential hazards related with the proactive activities. As detailed improvements, this paper introduces the mandatory and voluntary reporting system, normal operation safety survey, ATC quality assurance and the encouragement of just culture.

• Journal of radiological science and technology
• /
• v.29 no.2
• /
• pp.63-69
• /
• 2006

In diagnostic ultrasound, the quality of image affect to diagnose. To maintain suboptimal imaging uniformly, Quality Assurance of Ultrasound equipment should take periodically. This is article about examination the quality of image in diagnostic ultrasound to understand conditions of probes in hospitals. There is comparative study of convex and linear probes on ultrasound using tissue-mimicking phantom included simulated cysts, echogenic structures. The ultrasonic attenuation coefficient versus frequency of 0.5 dB is representative of normal liver and 0.7 dB is representative of fatty liver condition in ultrasound phantom. There are results of convex probe, 0.5 dB, vertical group, cystic masses, high contrast masses are mostly shown but 0.7 dB, mid level in vertical group, cystic masses and high contrast masses are nearly visible. In linear probe, 0.5 dB, mid level in vertical group, two or four of them are shown in cystic masses and high contrast masses but there are not visible in 11 of cases. 0.7 dB, there are mostly appear under 6 in vertical group, two or four of them show in cystic masses and high contrast masses and there are not shown in 40 of cases, besides. Linear probes in fatty liver condition of ultrasound instrument are not good in the quality of image practically. So there needs to be replace and fix of probes. Actually management of ultrasound probes is inadequate in hospitals. So if there are program of evaluation to check probes periodically in hospitals from establishment of the ultrasound equipment, there will get better image and have a suitable condition of instruments further more.

• Progress in Medical Physics
• /
• v.21 no.2
• /
• pp.223-231
• /
• 2010

We have taken surveys about total 72 departments of radiation oncology which is performing the treatment with linear accelerator and brachytherapy unit in Korea. The survey was included the research about the linear accelerator, brachytherapy, Also, we surveyed the various performance (QA period, manpower, time) of quality control for understanding of efficiency. The survey results show that the QA test of daily and weekly are almost same comparing to USA and Europe but the QA performance of monthly and yearly in Korea are 15.5 which is less than USA and Europe recommended QA item number of 17 to 21. The manpower and QA time in Korea also lower than 50% of USA and Europe recommended because the manpower and QA time limitation in Korea. It will be expected that the manual of quality management in each clinic could be appropriately established when combining the present results with previously published AAPM TG-40 and other protocols.