• 한국의학물리학회지:의학물리
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• 제28권3호
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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.

• 대한방사선기술학회지:방사선기술과학
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• 제41권5호
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• pp.437-444
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• 2018

Whole-Body counters have been used to evaluate the internal contamination of gamma emitting radionuclides. Among the whole-body counters used in domestic nuclear facilities, Fastscan made by CANBERRA contains 2 NaI(Tl) detectors and is generally used to monitor the primary internal exposure. It has the advantage of achieving MDA even with short time measurements. Accuscan is a bed type, and has good energy resolution because it is composed of HPGe detector. Since the Accuscan with better energy resolution than Fastscan has better able to identify radionuclides, it is used to monitor secondary internal exposure. Some nuclear facilities have only Fastscan. We analyzed statistically whether Fastscan is enough to ensure accuracy and precision comparing with Accuscan. To do this, we prepared a CRM created by the Korea Research Institute of Standards and Science. We also obtained the data of 6 Fastscans and 5 Accuscans in domestic nuclear facilities. As a result of the study, although Fastscan compared with Accuscan is not as accurate as the Accuscan, the precision is statistically same. However, accuracy of Fastscan is in compliance with international standards except low energy range. In terms of accuracy and precision except radionuclides emitting low energy, it is possible to measure radioactivity inside workers even in nuclear facilities where only Fastscan is used.

• 한국컴퓨터산업학회논문지
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• 제4권4호
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• pp.455-466
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• 2003

호주에 있는 사례연구로 캔버라관광 웹사이트를 채택함으로써 복잡한 의사결정과정에 적용된 인터넷 기능들에 대한 온라인 관광객들의 선호도를 조사하기 위해서 자의적 선택 웹 조사방법이 사용되었다 모집단으로서 이미 알려진 집주소와 전화번호들을 갖고 있는 우편조사와 전화조사와 같은 다른 전통적인 조사방법에 비해 웹에 기초한 조사방법을 사용하기에는 아직 시기상조이다. 이 연구에서 채택된 웹 조사 방법은 심각한 조사오류들을 발생시킬 수 있는 알려진 모집단이 없는 비확률표본추출에 의존하고 있다. 따라서 이 연구의 결과들은 자의적 선택 웹 조사에 대한 신뢰성을 확인하기 위하여 공식적으로 발행된 통계 자료들과 비교될 필요가 있다. 금번 연구조사는 자의적 선택 웹 조사방법이 어느 정도까지 타당화 될 수 있는 지를 논의한다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3293-3298
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• 2013

Background: The study investigated the influence of culturally-based health beliefs on engagement in healthy lifestyle behaviour. Specifically, the study compared levels of engagement between Western and Chinese youth in Australia and assessed the extent to which culture-specific attributions about the causes of illness, and health beliefs, predict engagement in healthy lifestyle behaviour. Materials and Methods: Ninety-four Western and 95 Chinese (N=189; Mean Age=20.8 years, SD=3 years) young adults completed an online questionnaire. Predictor variables were cultural health beliefs measured by the Chinese Cultural Views on Health and Illness scale (CCVH, Liang et al., 2008), and illness attributions beliefs measured by the Cause of Illness Questionnaire (CIQ, Armstrong and Swartzman, 1999). Outcomes variables were levels of engagement in healthy lifestyle behaviour. Results: Results indicated that Chinese participants have a significantly lower exercising rate and healthy dietary habits compared to the Western sample. Moreover, Chinese participants were found to believe more strongly than Westerners that cancer was associated with factors measured by the Traditional-Chinese-Model (TCM). Finally, the observed relationship between cultural health beliefs and physical inactivity was mediated by attributions of illness, in particular to the supernatural subscale, with the Sobel Test showing a significant mediation (z=-2.63, p=0.004). Conclusions: Mainstream approaches to encourage healthy lifestyles are unlikely to be effective when educating Chinese youth. Instead, health promotion programs should attempt to address the illness attribution beliefs and educate Chinese youth about the role of diet and exercise in prevention of diseases such as cancer.

• Nuclear Engineering and Technology
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• 제26권4호
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• pp.555-561
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• 1994

핵연료 건전성 점검을 위하여 다중채널분석기로 얻은 감마선 스펙트럼을 자동으로 빨리 분석하는 프로그램을 개발하였다. 핵연료의 건전성은 실시간 감시와 주기적인 시료 분석을 통한 원자로냉각재내의 방사선준위로 확인된다. 영광 3·4 호기의 경우, 실시간 감시 계통인 프로세스 방사선 감시 계통(PRMS)이 핵연료의 건전성을 확인한다. 현재, PRMS의 스펙트로미터 채널의 신호처리기는 단일채널 분석기이어서 오직 하나의 방사성핵종만을 파악할 수 있다. 따라서 PRMS를 개선하기 위해서는 단일채널분석기를 다중채널분석기로 대치하여야 한다. 이 프로그램은 실시간 모드와 수동모드로 실행되며, 모든 과정을 자동으로 수행한다. 미 국가표준국의 혼합 표준 선원에 대한 시험 결과는 상용 다중채널분석기인 Canberra System 100의 결과와 잘 일치하였다. 결론적으로 개발된 프로그램은 원자력발전소의 감마선 감시에 사용할 수 있을 것으로 보인다.

• Architectural research
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• 제13권2호
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• pp.13-21
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• 2011

Since 2002, Architecture Schools in Korea was changing long traditional architectural education system from 4 years generalized architectural engineering curriculum to 5 years professional architecture program. Until 2010, 76 architecture schools have changed their program to 5 years course which was focused to design studio education. It was a very rapid change and there was not much time develop their own system which could represent institutional identity, character of students and local environment. Korea joined as a regular member of Canberra Accord in 2010 and it is meaningful to compare Korean architecture program contents to another country education contents. US architecture programs were selected for this comparison study. The goals of this study are to create a comparable understanding the form of contents of Architectural Education in US and Korea and to verify the substantial equivalence of these systems. To achieve above goals, three public institutes of each country were selected and analyzed with general information, history, resources, curriculum and the matrix of Student Performance Criteria for quantitative comparison. For qualitative comparison education context of programs were analyzed with program missions, the way of advising, professional connection and distribution of faculty loads.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권10호
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• pp.5197-5218
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• 2019

Large-scale retrieval algorithm is problem for visual analyses applications, along its research track. In this paper, we propose a high-efficiency region division-based image retrieve approaches, which fuse low-level local color histogram feature and texture feature. A novel image region division is proposed to roughly mimic the location distribution of image color and deal with the color histogram failing to describe spatial information. Furthermore, for optimizing our region division retrieval method, an image descriptor combining local color histogram and Gabor texture features with reduced feature dimensions are developed. Moreover, we propose an extended Canberra distance method for images similarity measure to increase the fault-tolerant ability of the whole large-scale image retrieval. Extensive experimental results on several benchmark image retrieval databases validate the superiority of the proposed approaches over many recently proposed color-histogram-based and texture-feature-based algorithms.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제12권3호
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• pp.179-191
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• 2008

Although problem solving was a major focus of mathematics education research in many countries throughout the 1990s, not enough is known about how people best acquire problem-solving skills. This paper is an attempt to advance further development of problem-solving skills of talented school students through combination of some methods accessible from curriculum knowledge and more special techniques that are beyond curriculum. Analysis of various problems is provided in detail. Educational aspects of challenging problems in mathematical contests up to IMO level are, also, taken into account and discussed in the paper.

• International journal of advanced smart convergence
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• 제12권2호
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• pp.34-46
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• 2023

A growing number of large scale knowledge graphs raises several issues how knowledge graph data can be organized, discovered, and integrated efficiently. We present a novel semantic-based mashup platform for contents convergence which consists of acquisition, RDF storage, ontology learning, and mashup subsystems. This platform servers a basis for developing other more sophisticated applications required in the area of knowledge big data. Moreover, this paper proposes an entity matching method using graph convolutional network techniques as a preliminary work for automatic classification and discovery on knowledge big data. Using real DBP15K and SRPRS datasets, the performance of our method is compared with some existing entity matching methods. The experimental results show that the proposed method outperforms existing methods due to its ability to increase accuracy and reduce training time.

• 천문학회보
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• 제46권2호
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• pp.49.3-50
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• 2021

In this study, we aim to identify low-mass members of nearby, young stellar moving groups (NYMGs) from Gaia EDR3. The spatio-kinematic membership probabilities of the NYMGs were calculated utilizing the Bayesian membership probability calculation tool developed in our previous study. The youth of these spatio-kinematic members were assessed using positions on color-magnitude diagrams. We identified ~2200 new low-mass NYMG candidate members, that can be confirmed by follow-up spectroscopic observations. We performed pilot spectroscopic observation with WiFeS at Siding Spring Observatory observing 79 candidates, and about 80 per cent of them were confirmed as members.