• 제목/요약/키워드: Assessment and analysis

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Region of Interest Heterogeneity Assessment for Image using Texture Analysis

  • Park, Yong Sung;Kang, Joo Hyun;Lim, Sang Moo;Woo, Sang-Keun
    • 한국컴퓨터정보학회논문지
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    • 제21권11호
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    • pp.17-21
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    • 2016
  • Heterogeneity assessment of tumor in oncology is important for diagnosis of cancer and therapy. The aim of this study was performed assess heterogeneity tumor region in PET image using texture analysis. For assessment of heterogeneity tumor in PET image, we inserted sphere phantom in torso phantom. Cu-64 labeled radioisotope was administrated by 156.84 MBq in torso phantom. PET/CT image was acquired by PET/CT scanner (Discovery 710, GE Healthcare, Milwaukee, WI). The texture analysis of PET images was calculated using occurrence probability of gray level co-occurrence matrix. Energy and entropy is one of results of texture analysis. We performed the texture analysis in tumor, liver, and background. Assessment textural features of region-of-interest (ROI) in torso phantom used in-house software. We calculated the textural features of torso phantom in PET image using texture analysis. Calculated entropy in tumor, liver, and background were 5.322, 7.639, and 7.818. The further study will perform assessment of heterogeneity using clinical tumor PET image.

위해성평가의 불확실도 분석과 활용방안 고찰 (Uncertainty Analysis and Application to Risk Assessment)

  • 조아름;김탁수;서정관;윤효정;김필제;최경희
    • 한국환경보건학회지
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    • 제41권6호
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    • pp.425-437
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    • 2015
  • Objectives: Risk assessment is a tool for predicting and reducing uncertainty related to the effects of future activities. Probability approaches are the main elements in risk assessment, but confusion about the interpretation and use of assessment factors often undermines the message of the analyses. The aim of this study is to provide a guideline for systematic reduction plans regarding uncertainty in risk assessment. Methods: Articles and reports were collected online using the key words "uncertainty analysis" on risk assessment. Uncertainty analysis was conducted based on reports focusing on procedures for analysis methods by the World Health Organization (WHO) and U.S. Environmental Protection Agency (USEPA). In addition, case studies were performed in order to verify suggested methods qualitatively and quantitatively with exposure data, including measured data on toluene and styrene in residential spaces and multi-use facilities. Results: Based on an analysis of the data on uncertainty, three major factors including scenario, model, and parameters were identified as the main sources of uncertainty, and tiered approaches were determined. In the case study, the risk of toluene and styrene was evaluated and the most influential factors were also determined. Five reduction plans were presented: providing standard guidelines, using reliable exposure factors, possessing quality controls for analysis and scientific expertise, and introducing a peer review system. Conclusion: In this study, we established a method for reducing uncertainty by taking into account the major factors. Also, we showed a method for uncertainty analysis with tiered approaches. However, uncertainties are difficult to define because they are generated by many factors. Therefore, further studies are needed for the development of technical guidelines based on the representative scenario, model, and parameters developed in this study.

기후변화 취약성 평가 분석도구 개발에 관한 연구: 충남지역 산불 취약성을 중심으로 (Development of a Climate Change Vulnerability Assessment Analysis Tool: Based on the Vulnerability Assessment of Forest Fires in Chungcheongnam-do)

  • 윤수향;이상신
    • 한국기후변화학회지
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    • 제8권3호
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    • pp.275-285
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    • 2017
  • Chungnam region has established and executed the 2nd Climate Change Adaptation Initiative Execution Plan (2017~2021) based on the Framework Act on Low Carbon, Green Growth. The Execution Plan is established based on the results of climate change vulnerability assessment using the CCGIS, LCCGIS, and VESTAP analysis tools. However, the previously developed climate change vulnerability assessment tools (CCGIS, LCCGIS, VESTAP) cannot reflect the local records and the items and indices of new assessment. Therefore, this study developed a prototype of climate change vulnerability assessment analysis tool that, unlike the previous analysis tools, designs the items and indices considering the local characteristics and allows analysis of grid units. The prototype was used to simulate the vulnerability to forest fires of eight cities and seven towns in Chungcheongnam-do Province in the 2010s, 2020s, and 2050s based on the RCP (Representative Concentration Pathways) 8.5 Scenario provided by the Korea Meteorological Administration. Based on the analysis, Chungcheongnam-do Province's vulnerability to forest fires in the 2010s was highest in Seocheon-gun (0.201), followed by Gyeryong-si (0.173) and Buyeo-gun (0.173) and the future prospects in the 2050s was highest in Seocheon-gun (0.179), followed by Gyeryong-si (0.169) and Buyeo-gun (0.154). The area with highest vulnerability to forest fires in Chungcheongnam-do Province was Biin-myeon, Seocheon-gun and the area may become most vulnerable was Pangyo-myeon, Seocheon-gun. The prototype and the results of analysis may be used to establish the directions and strategies in regards to the vulnerability to wild fires to secure each local government's 2nd execution plan and attainability.

수소 충전소에 대한 정량적 안전성 평가 (Quantitative Safety Assessment for Hydrogen Station)

  • 성대현;이광원;김태훈;오동석;오영달;서두현;김영규;김은정
    • 한국안전학회지
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    • 제27권3호
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    • pp.111-116
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    • 2012
  • This study is about the quantitative safety assessment of hydrogen station in Korea operating with on-site type. This was written by background information that before qualitative safety assessment to write. For the qualitative safety assessment method, the study used FMEA(failure mode & effect analysis) and HAZOP(hazard & operability), and adopted the FTA(fault tree analysis) as the quantitative safety assessment method. To write the FTA, we wrote FT by Top event that hydrogen leakage can be called most serious accident of hydrogen station. Each base event collect reliability data by reliability data handbook, THERP-HRA and estimation of the engineering. Assessment looked at the high frequency and the possible risk through Gate, Importance, m.cutsets analysis.

중국 중학교 교사들의 수행평가에 관한 관심도와 실행 수준 분석 - 북경시 중심으로- (Analysis of Teachers' Concern and Levels of Use on Performance Assessment in China Middle School)

  • 이서우;김태현;김석우
    • 수산해양교육연구
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    • 제25권1호
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    • pp.29-39
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    • 2013
  • The purpose of this study is to analyze middle school teachers' concern about and implementation degree of performance assessment in China. The research questions are as follows: First, what kind of concern is held by middle school teachers who implement performance assessment? Second, is there any significant difference in stages of concern the teachers on performance assessment according to their gender, education level and teaching career? Third, which level of use is shown by middle school teachers who implement performance assessment? Fourth, what is the correlation between middle school teachers' Stages of Concern and Levels of Use on performance assessment? This study was conducted based on a Concerns-Based Adoption Model (Hall, 1973; CBAM) that viewed teachers as the most primary factor of the execution of innovation, in this case, performance assessment. Performance assessment is assessment based on observation and judgement (Stiggins, 1994), and require test takers to complete a process or produce a product in a context that closely resembles real-life situations. The subjects of this study were randomly sampled from 120 middle school teachers throughout Bei-Jing, China. The questionnaires were distributed to them by mail, and they were asked to return their questionnaire by mail. The collect data were analyzed by SPSS/WIN 18.0 program in terms of frequency, correlation, or MANOVA. Frequency analysis was used to analyze concern of middle school teachers on performance assessment. To gain an frequency of the individuals in each stage, we regarded the stage in which a teacher had his/her highest score as his/her relevant stage. Correlation analysis was adopted to identify the correlation between teachers' stage of concern and level of use. To analyze the difference of the concern of China middle school teachers on performance assessment according to their individual background variables such as gender, education level, and teaching career, MANOVA was performed.

Design and Implementation of ELAS in AI education (Experiential K-12 AI education Learning Assessment System)

  • Moon, Seok-Jae;Lee, Kibbm
    • International Journal of Advanced Culture Technology
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    • 제10권2호
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    • pp.62-68
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    • 2022
  • Evaluation as learning is important for the learner competency test, and the applicable method is studied. Assessment is the role of diagnosing the current learner's status and facilitating learning through appropriate feedback. The system is insufficient to enable process-oriented evaluation in small educational institute. Focusing on becoming familiar with the AI through experience can end up simply learning how to use the tools or just playing with them rather than achieving ultimate goals of AI education. In a previous study, the experience way of AI education with PLAY model was proposed, but the assessment stage is insufficient. In this paper, we propose ELAS (Experiential K-12 AI education Learning Assessment System) for small educational institute. In order to apply the Assessment factor in in this system, the AI-factor is selected by researching the goals of the current SW education and AI education. The proposed system consists of 4 modules as Assessment-factor agent, Self-assessment agent, Question-bank agent and Assessment -analysis agent. Self-assessment learning is a powerful mechanism for improving learning for students. ELAS is extended with the experiential way of AI education model of previous study, and the teacher designs the assessment through the ELAS system. ELAS enables teachers of small institutes to automate analysis and manage data accumulation following their learning purpose. With this, it is possible to adjust the learning difficulty in curriculum design to make better for your purpose.

도서지역의 효율적 토지적성평가 방안 (The Method for Efficient Land Suitability Assessment in an Island Group)

  • 고홍석;박송주;고남영;성동권
    • 대한공간정보학회지
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    • 제13권3호
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    • pp.15-24
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    • 2005
  • 국토의 난개발을 방지하기 위해 도입된 토지적성평가는 공간 및 물리적인 특성이 서로 다른 육지와 도서지역의 평가기준을 일률적으로 적용하는 데 있어서 많은 문제점을 내포하고 있다. 본 연구에서는 공간적 지리적 지역적 특성이 뚜렷이 다른 도서지역의 효율적 토지적성평가방법의 연구를 위해서 생활권역을 고려한 평가단위와 이를 기반으로 한 평가지표 개발 등에 관하여 연구였다. 평가권역을 고려한 평가단위에서는 중생활권의 평가가 가장 양호하였으며 거리분석에 있어서는 해양을 고려한 거리 분석방법을 제안하여 도서간의 접근성을 고려한 평가방법을 제시하였다.

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뇌파와 감성평가 기반의 스크린 상 특정 디스플레이 위치 선호도 평가에 관한 기초연구 (A Preliminary Study on the Preference Assessment on Individuals with Specific Display Location in Screen based on Electroencephalogram and Emotional Assessment)

  • 왕창원;민세동
    • 전기학회논문지
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    • 제63권7호
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    • pp.968-975
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    • 2014
  • This paper proposed a evaluation method for individual's subjective preferred location using EEG and emotional assessment. Visual stimulus were sequentially presented a total six points(the top and the bottom of the left, the top and the bottom of the center and the top and the bottom of the right on the screen). EEG were measured from twenty subjects according to each six points. At the same time, we were executed evaluation of subjects preferred location from emotional assessment. Alpha and beta wave were measured in Fp1, Fp2, F7 and F8 location, followed by ten to twenty electrode system. Correlations and variations of alpha and beta wave from each channel were calculated and analyzed. Because of the number of subjects population under 30, we used Speareman test for a correlation analysis between alpha and beta wave. Also, emotional assessments which compose of visual sense harmony, visual sense stability, stability of position and the visibility were performed and were analyzed by average and frequency. After visual stimulus, emotional assessments were performed. From the variance analysis of EEG, beta wave from F7 was appeared statistically significant as significance probability of 0.006. Also, between alpha wave and beta wave appeared a negative correlation(r=-0.190). From the post-hoc test of F7 beta wave, location 1, 5 and 6 appeared to difference statistically significant. Emotional assessment result according to six positions showed 0.00 significance probability. Thus, location and emotional assessment appeared to influence on each other. From the average and frequency analysis of emotional assessment, location 2 showed obtained of best emotional assessment score and appeared lower beta wave than other locations. Finally, most subjects showed a preference for location 2. Through obtained results in this paper, will be helpful to about human emotional assessment and EEG research.

강사장교의 초기형상과 비선형성을 고려한 확률론적 구조안전성 평가 (Probabilistic Structural Safety Assessment Considering the Initial Shape and Non-linearity of Steel Cable-Stayed Bridges)

  • 방명석;한성호;이우상;이진옥
    • 한국안전학회지
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    • 제25권3호
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    • pp.91-99
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    • 2010
  • In this study, the advanced numerical algorithm is developed which can performed the static and dynamic stochastic finite element analysis by considering the effect of uncertainties included in the member stiffness of steel cable-stayed bridges and seismic load. After conducting the linear and nonlinear initial shape analysis, the advanced numerical algorithm is the assessment tool which can performed structural the response analysis considering the static linearity and non-linearity of before or after induced intial tensile force, and examined the reliability assessment more efficiently. The verification of the developed numerical algorithm is evaluated by analyzing the regression analysis and coefficient of correlation using the direct monte carlo simulation. Also, the dynamic response characteristic and coefficient of variation of the steel cable-stayed bridge is calculated by considering the uncertainty of random variables using the developed numerical algorithm. In addition, the quantitative structural safety of the steel cable-stayed bridges is evaluated by conducting the reliability assessment based upon the dynamic stochastic finite element analysis result.

Ergonomics Risk-Assessment Methods in Shipbuilding: Application of OWAS Considering Work load and Frequency for Risk Factor Analysis of WMSDs

  • Lee, Jun-Youb;Seo, Hyun-Soo
    • 대한인간공학회지
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    • 제31권1호
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    • pp.185-189
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    • 2012
  • Objective: The aim of this paper is to introduces Hyundai Heavy Industry's ergonomic risk assessment tool, H-OWAS, which is considering work load and frequency compared to the OWAS. Background: As prevalence of work-related musculoskeletal disorders(WMSDs) in ship building industries has been much higher than that in other industries, most of the large scaled corporations have implemented their own prevention program since legislation on the prevention of WMSDs had introduced in 2003. Method: This paper introduces WMSDs prevention program, HEMP(HHI Ergonomics Management Program) which consists of risk assessment, improvement efforts of working environments, medical treatment and training/evaluation and describes how to operate the program. We also describe application of OWAS method considering work load and frequency for risk factor analysis(H-OWAS) and shows methodology for assessing the ergonomic risk factor. And comparison of the assessment results between OWAS and H-OWAS is carried out by statistical analysis. Result: There was statistically significant difference in the assessment results between OWAS and H-OWAS, and regression shows H-OWAS explains the borg's scale of perceived exertion more clearly than OWAS. Conclusion: H-OWAS has been proved more effective tool than OWAS to evaluate ergonomic risk factor under real working condition. Application: H-OWAS can be widely applied to the many other companies when implementing the ergonomics risk assessment.