• Title/Summary/Keyword: Quality verification

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Isocenter Verification Using Linac-Gram Films Taken with Angiolocalizer : Improved Quality Assurance of Fractionated Stereotactic Radiation Therapy(FSRT) (Angiolocalizer를 사용하여 얻어진 Linac-Gram을 이용한 조사야 중심의 정확도 평가 (FSRT의 진보된 Quality Assurance))

  • Cho, Jung-Keun;Park, Young-Hwan;Ju, Sang-Kyu;Kim, Young-Gon;Cho, Hyun-Sang
    • The Journal of Korean Society for Radiation Therapy
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    • v.9 no.1
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    • pp.25-28
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    • 1997
  • With the advances in radiation therapy technology and equipment, the need for more accurate and safer radiation delivery to the target region has been continuously growing. Stereotactic Radiosurgery(SRS) is a good example of $^{\ast}Accuracy^{\ast}$ but has a substantial risk of causing severe late neurological damages. Fractionated Stereotactic Radiation Therapy(FSRT) is a modification of SRS enabling conventional fractionation with maintaining accuracy using noninvasive and relocatable frame. Verification of mechanical accuracy in FSRT has been done according to the manufacture's recommendations using RLPP, LTLF, and Depth-helmet. In order to reinforce this, we have developed additional novel verification procedure using Linac-grams with the Angiolocalizer attached on the GTC frame, which are then digitized into the planning software(X-Knife) to generate the three dimensional coordinates for cmoparison. This method has been successful in such ways that the anatomical landmarks are identifiable on the Linac-gram films and that the serial comparisons of the stereotactic coordinates of the isocenter are possible with more certainty a along the FSRT course than before.

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A Study on the Verification of Crashworthiness for Fuel System of Military Rotorcraft (군용 회전익항공기 연료계통 내추락성 입증에 관한 연구)

  • Sangsoo Park;Junmo Yang;Munguk Kim;Jaechul Kim
    • Journal of Aerospace System Engineering
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    • v.17 no.1
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    • pp.16-23
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    • 2023
  • The aircraft fuel system performs a number of functions such as supplying fuel, transferring fuel between fuel tanks, and measuring the amount of residual fuel in each fuel tank. Since it is a direct cause of fire hazard in crash incident, it is a must to improve survivability of crew members by designing the airframe to tolerate expected crash impact. The civil aviation authority requires intensive verification of the fuel system design to determine precise application of the airworthiness requirement. Research activity on airworthiness certification criteria and verification scheme is still insufficient, although it has a significant importance. In this paper, as part of a study to improve flight safety by developing guidelines for demonstrating fuel system crash resistance, analysis results of fuel system crash-related airworthiness certification standards, verification scheme, and cases study applicable to military rotorcraft have been reviewed.

Excellence for Organization Quality Management Innovation Challenge -Comparison of Korea and China- (초우량 조직을 위한 품질경영혁신 도전 -한국과 중국의 비교-)

  • Kim, Gye-Soo;Xu, Da-Peng
    • Journal of Korean Society for Quality Management
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    • v.41 no.4
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    • pp.499-512
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    • 2013
  • Purpose: Quality Innovation Managements recently focus on developing relationship with customers to meet their requirements and enhance loyalty in the competitive environments in Countries. The purpose of this study is to explore the effects of innovation, quality, satisfaction and customer loyalty. Methods: After reviewing the literatures, the structural equation modeling (SEM) was conducted test the research model. The data was collected from Quality Leader by the questionnaire In Korea and China. Results: The results of SEM show that hardware innovation quality have a positive effect on customer satisfaction. Customer Satisfaction have a positive effect on customer satisfaction. Conclusion: The authors demonstrate that the hardware innovation quality is related positively to customer satisfaction. And customer satisfaction has a positive effect on customer loyalty. A number of notable findings are reported including the empirical verification that hardware innovation quality, customer satisfaction, and customer loyalty may all be directly related to business performance.

Performance improvement of text-dependent speaker verification system using blind speech segmentation and energy weight (Blind speech segmentation과 에너지 가중치를 이용한 문장 종속형 화자인식기의 성능 향상)

  • Kim Jung-Gon;Kim Hyung Soon
    • MALSORI
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    • no.47
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    • pp.131-140
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    • 2003
  • We propose a new method of generating client models for HMM based text-dependent speaker verification system with only a small amount of training data. To make a client model, statistical methods such as segmental K-means algorithm are widely used, but they do not guarantee the quality or reliability of a model when only limited data are avaliable. In this paper, we propose a blind speech segmentation based on level building DTW algorithm as an alternative method to make a client model with limited data. In addition, considering the fact that voiced sounds have much more speaker-specific information than unvoiced sounds and energy of the former is higher than that of the latter, we also propose a new score evaluation method using the observation probability raised to the power of weighting factor estimated from the normalized log energy. Our experiment shows that the proposed methods are superior to conventional HMM based speaker verification system.

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Calibration and Verification of a Tidal Prism Eutrophication Model for the Lynnhaven Bay (U.S.A)

  • PARK Kyeong;KUO Albert Y.
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.6
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    • pp.964-973
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    • 1997
  • A tidal prism eutrophication model, an one-dimensional intertidal model, is developed to study water quality conditions at small coastal basins and tidal creeks. The model simulates the physical transport processes using the concept of tidal flushing. The concept is simple and straightforward, and thus is ideal for small coastal basins with complex geometry. The model, having twenty-four state variables in the water column, simulates salinity, temperature, dissolved oxygen, three algal groups, and the cycles of carbon, nitrogen, phosphorus and silica. The model is applied to the Lynnhaven Bay, a small coastal basin of Chesapeake Bay in U.S.A. The model is calibrated using the field data collected in 1994, and then is verified using the independently collected data in 1980. The model overall gives a good reproduction of the field data, partly owing to the data collected from the field surveys specifically designed for the model application. This paper presents the procedure, and the results of the model calibration and verification.

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Verification Methods of ATE for TICN System (전술정보통신체계 ATE 유효성 검증 방안)

  • Bak, HyeonJeong;Kim, JinSung
    • Journal of Korea Society of Industrial Information Systems
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    • v.25 no.4
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    • pp.17-27
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    • 2020
  • In this paper, we proposed verification methods to prove the effectiveness of automatic test equipment (ATE) for weapon systems. Since the test results from the unproven ATE is not reliable and its use is limited as objective data, it is essential to verify the test equipment in order to guarantee the quality level of the unit under test (UUT). Through the suggested methods, it is applied to the ATE of the tactical information communications network (TICN) system to confirm the verification results and to describe the validation results.

The Study on Setting up KTX-II's RAM Goals for Requirement Train-set (고속차량(KTX-II) RAM 목표값 설정을 통한 소요량 연구)

  • Cha, Jae-Hwan;Chung, In-Soo;Kim, Jong-Woon;Yu, Yang-Ha
    • Proceedings of the KSR Conference
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    • 2009.05b
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    • pp.191-198
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    • 2009
  • There are almost no studies on verification of requirements for high speed rolling stocks by means of RAM goals and on setting RAM goals by means of verification on practical reliability, availability and maintainability for high speed rolling stocks though they are covered in specification of an order that RAM goals asked of rolling stocks are shown for gaining high quality of them and availability when they are in operation. This study is for estimating number of high speed train-sets that would be supplementarily placed an order through verification of RAM goals of a project for the introduction of KTX-II 100 cars. It verify that optimized requirements for high speed rolling stocks by relatively comparison with between requirements for train-sets through setting RAM goals and requirements for train-sets through analysis of prospects for management balance with high speed rolling stocks.

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Concealment of iris features based on artificial noises

  • Jiao, Wenming;Zhang, Heng;Zang, Qiyan;Xu, Weiwei;Zhang, Shuaiwei;Zhang, Jian;Li, Hongran
    • ETRI Journal
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    • v.41 no.5
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    • pp.599-607
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    • 2019
  • Although iris recognition verification is considered to be the safest method of biometric verification, studies have shown that iris features may be illegally used. To protect iris features and further improve the security of iris recognition and verification, this study applies the Gaussian and Laplacian mechanisms and to hide iris features by differentiating privacy. The efficiency of the algorithm and evaluation of the image quality by the image hashing algorithm are selected as indicators to evaluate these mechanisms. The experimental results indicate that the security of an iris image can be significantly improved using differential privacy protection.

Uncertainty Assessment: Relative versus Absolute Point Dose Measurement for Patient Specific Quality Assurance in EBRT

  • Mahmood, Talat;Ibrahim, Mounir;Aqeel, Muhammad
    • Progress in Medical Physics
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    • v.28 no.3
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    • pp.111-121
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    • 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.

A study of Quality evaluation for medical linear accelerator using Electronic Portal Imaging (전자포탈영상 (EPI)을 이용한 의료용 선형가속기의 성능평가에 관한 연구)

  • 윤성익;권수일;추성실
    • Progress in Medical Physics
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    • v.9 no.2
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    • pp.105-113
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    • 1998
  • Accurate radiation dosimetric characters is very important to determine of dose to a radiotherapeutic patient. Medical linear accelerators have been developed not only its new quality of convenient operation but also electric moderation. It is reliable to measure more detail physical parameter that linac's internal ability. Typically, radiation dosimetric tool is classified ionization chamber, film, thermoluminescence dosimeter, etc. Nowaday, Electronic Portal Imaging Device is smeared in radiation field to verification of treatment region. EPID's image was focused that using both on-line image verification and absolutely minimum absorbed dose during radiotherapy. So, Electronic Portal Imaging was tested for quality evaluation of medical linear accelerator had its pure conditional flash. This study has performed symmetry, Light/Radiation field congruence, and energy check, geometry difference on wedge filter using a liquid filled ion chamber (EPID). Prior to irradiated on EPID, high energy photon beam is checked with ion chamber. Using these results more convenient dosimetric method is accomplished by EPID that taken digital image. Medical image is acquired with EPID too. Therefore, EPID can be analyzed by numerical information for what want to see or get more knowledge for natural human condition.

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