• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.668-674
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• 2020

Quality Assurance (QA) is essential to provide effective hyperthermia, but in the case of a problem with a hyperthermia cancer therapy system in Korea, the manufacturers or venders are repairing and maintaining the system. In Korea, if an error occurs in the hyperthermia system, the manufacturer and sales agent are repairing and maintaining it. There is no QA protocol suitable for the domestic situation. This study is based on the QA guidelines recommended by institutions such as European Society for Hyperthermia Oncology (ESHO), Hellenic Society of Oncologic Hyperthermia (HSOH), and the results of questionnaires to hospitals that have hyperthermia cancer therapy systems in Korea. By developing an optimized QA protocol, we aim to reduce the errors and inaccuracies that can occur in during hyperthermia such as measurement of temperature, instrumentation, and heat transfer. In addition, we will visit a hospital with a hyperthermia cancer therapy system in Korea to perform a QA based on this study, and study to specify tolerances and accurate QA set-up parameters using the measured QA results.

• Journal of Radiation Protection and Research
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• v.44 no.1
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• pp.32-42
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• 2019

Background: There have been much efforts to develop the proper and realistic machine Quality Assurance (QA) reflecting on real Volumetric Modulated Arc Therapy (VMAT) plan. In this work we propose and test a special VMAT plan of plan-class specific (pcsr) QA, as a machine QA so that it might be a good solution to supplement weak point of present machine QA to make it more realistic for VMAT treatment. Materials and Methods: We divided human body into 5 treatment sites: brain, head and neck, chest, abdomen, and pelvis. One plan for each treatment site was selected from real VMAT cases and contours were mapped into the computational human phantom where the same plan as real VMAT plan was created and called plan-class specific reference (pcsr) QA plan. We delivered this pcsr QA plan on a daily basis over the full research period and tracked how much MLC movement and dosimetric error occurred in regular delivery. Several real patients under treatments were also tracked to test the usefulness of pcsr QA through comparisons between them. We used dynalog file viewer (DFV) and Dynalog file to analyze position and speed of individual MLC leaf. The gamma pass rate from portal dosimetry for different gamma criteria was analyzed to evaluate analyze dosimetric accuracy. Results and Discussion: The maxRMS of MLC position error for all plans were all within the tolerance limit of < 0.35 cm and the positional variation of maxPEs for both pcsr and real plans were observed very stable over the research session. Daily variations of maxRMS of MLC speed error and gamma pass rate for real VMAT plans were observed very comparable to those in their pcsr plans in good acceptable fluctuation. Conclusion: We believe that the newly proposed pcsr QA would be useful and helpful to predict the mid-term quality of real VMAT treatment delivery.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.134-141
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• 2014

A testing inspection is one of the important in the industry, owing to determine the reliability and directivity of testing inspection results. Therefore, the quality assurance and quality control (QA/QC) work which performed by personnel not directly in the inventory compilation development, in testing inspection must be thoroughly considered. Some agencies for environmental test inspection, they sometimes misunderstood that the QA/QC was ended with proficiency testing performance and on-site assessment by a director. Thus, results were often calculated without QA/QC work by self manual when conducting test. The objective of this study was to improve reliability of testing and inspection agency through the QA/QC case study which basically performed to raising reliability of testing and inspection agency. In this study, it increased reliability of result by verifying calibration curve (IC, ICV, CCV), blank, accuracy (LCS, MS) and precision as QA/QC performance, while performing investigation of soil contamination in mining areas. This study suggests that reliability establishing method of test result and management method of analysis process, through the QA/QC instance of testing agency.

• Journal of Aerospace System Engineering
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• v.3 no.1
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• pp.6-11
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• 2009

It is anticipated that quality assurance for the Ka band Communication Payload System(COPS) development program of the communication, Ocean & Meteorological Satellite(COMS) may be a core technical factor to be concerned in order to avoid any failure, and to assure its final performance during the mission lifetime in space. Those can be managed and verified and assessed by performing the Quality Assurance (QA) and risk management which helps to prevent and to reduce the critical fails. This paper introduces the Product Assurance (PA) system and procedures for controlling and monitoring sub-contractors which were participated in Ka band Communication Payload System (COPS) development. Also this paper shows Quality Assurance (QA) procedures and detailed their processes for assured the product performed by local companies from site survey for selecting companies to delivery of their equipment.

• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.69-72
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• 1999

We present a method of quality assurance (QA) for dose and dose distribution anticipated in treatment planning at proton therapy using a particle-based simulation method.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.277-287
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• 2004

This study presents a method of quality category classification by safety, maturity, complexity, and what types and extent of controls and verifications are applied to specific products and services during the various stages of a nuclear facility life cycle. All products, services and processes have various controls and verifications built in to ensure they perform their functions satisfactorily. The highest grade should require the most stringent application of the quality assurance requirements ; while, the lowest grade should require the least stringent. When products or services are modified, the assigned grade of quality assurance requirements could become more stringent or less stringent depending on the significance in nuclear safety. Applying QA program always costs money, and they should be applied and focused to the extent where necessary and not applied or applied to a lesser degree for less important activities. An efficient QA program should be developed to satisfy the necessary requirements and to ensure the required confidence in quality, but without unnecessary stipulations. Not all the requirements of QA standard must be applied identically to all products and services which are to be provided.

• Progress in Medical Physics
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• v.30 no.4
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• pp.128-138
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• 2019

Purpose: Segmental analysis of volumetric modulated arc therapy (VMAT) is not clinically used for compositional error source evaluation. Instead, dose verification is routinely used for plan-specific quality assurance (QA). While this approach identifies the resultant error, it does not specify which machine parameter was responsible for the error. In this research study, we adopted an approach for the segmental analysis of VMAT as a part of machine QA of linear accelerator (LINAC). Methods: Two portal dose QA plans were generated for VMAT QA: a) for full arc and b) for the arc, which was segmented in 12 subsegments. We investigated the multileaf collimator (MLC) position and dosimetric accuracy in the full and segmented arc delivery schemes. A MATLAB program was used to calculate the MLC position error from the data in the dynalog file. The Gamma passing rate (GPR) and the measured to planned dose difference (DD) in each pixel of the electronic portal imaging device was the measurement for dosimetric accuracy. The eclipse treatment planning system and a MATLAB program were used to calculate the dosimetric accuracy. Results: The maximum root-mean-square error of the MLC positions were <1 mm. The GPR was within the range of 98%-99.7% and was similar in both types of VMAT delivery. In general, the DD was <5 calibration units in both full arcs. A similar DD distribution was found for continuous arc and segmented arcs sums. Exceedingly high DD were not observed in any of the arc segment delivery schemes. The LINAC performance was acceptable regarding the execution of the VMAT QA plan. Conclusions: The segmental analysis proposed in this study is expected to be useful for the prediction of the delivery of the VMAT in relation to the gantry angle. We thus recommend the use of segmental analysis of VMAT as part of the regular QA.

• Quality Improvement in Health Care
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• v.1 no.1
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• pp.6-12
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• 1994

• Progress in Medical Physics
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• v.23 no.2
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• pp.123-126
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• 2012

For the purpose of quality assurance (QA) of the blood irradiator, QA programs for daily, monthly, and yearly were developed. For daily tests, simple items for basically operating the machine are recommended. For monthly and yearly tests, the measurement of dose to assure the dose delivery system are performed by a dosimetry devices (Glass dosimeter jig) developed in this study. The QA program is practical for clinical environment.

• Proceedings of the Korean Society of Computer Information Conference
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• 2018.01a
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• pp.237-240
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• 2018

현재 e스포츠 시장은 게임 산업의 성장과 맞물려 매우 큰 규모로 확대되고 있고, 업종을 불문하고 다양한 국제적인 기업과 스포츠 구단이 진출하고 있는 실정이다. 본 논문에서는 컴퓨팅 관련 산업에 있어서 수요와 공급의 중간 매체의 역할을 하는 품질보증(QA : Quality Assurance)이 게임 산업의 한 분야인 e스포츠 산업을 위해 수행할 역할과 상호작용에 대한 중요성과 필요성을 제시하고자 한다.