Детальная информация

The subject of the graduate qualification work is «State of the Art Development trends in Uncertainty Safety Analysis of Dose Assessment for Nuclear». This work is focused on making comprehensive review of the uncertainty safety analysis of dose assessment in Nuclear Power Plants, particularly in the event of accidents and the specific tasks are: 1. Review of radiological assessments related to the Fukushima Daiichi nuclear disaster (FDND). 2. Comprehensive classification of published articles on uncertainty dose analysis 3. Evaluating the uncertainty in dose assessment post-NPP accidents. The catastrophic events that can arise from nuclear power plant accidents have made the accurate assessment of radiation dose to the public and environment a critical component of nuclear safety. However, inherent uncertainties in dose assessment due to measurement limitations, modeling flaws, and parameter estimation mistakes warrant a comprehensive analysis to ensure the reliability of safety evaluations. This thesis examines the state of the art in managing uncertainties within the context of dose assessments following NPP accidents, with a specific focus on development trends aimed at improving these assessments. Initially, the study touches into the radiological assessment related to the Fukushima Daiichi nuclear disaster, providing an in-depth review of the accident and its subsequent dose assessment methodologies while highlighting the encountered uncertainties. A comprehensive review of existing literature follows, discussing the various forms of uncertainty in dose assessment and identifying research trends and knowledge gaps. The research then evaluates the existing methods through case studies, comparing different NPP accident dose assessments, and examining how uncertainties have been addressed in past events, particularly in terms of their impact on public safety decision-making. Lastly, emerging technologies and techniques in the field of uncertainty safety analysis are explored, and recommendations for enhancing uncertainty management in dose assessments are given, along with proposed directions for future research. Overall, the thesis aims to consolidate the current understanding of uncertainty in dose assessments post-NPP accidents and to contribute to advancing the fields capacity to safeguard public and environmental health in the face of potential nuclear threats. To achieve these results, the materials utilized include a vast array of published articles, regulatory documents, and existing uncertainty analysis studies pertinent to the field of nuclear accidents. MS office (Word and PowerPoint) was used for creating thesis final report as well as presentations.

• ABSTRACT
• INTRODUCTION
• 1 CHAPTER 1: REVIEW OF RADIOLOGICAL ASSESSMENT RELATED TO FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT
  • 1.1 Background Of the Review
  • 1.2 Data Collection
    • 1.2.1 Classification criteria
  • To carry out a comprehensive review of the dose assessment studies following the Fukushima Daiichi nuclear disaster, this review employs a classification system. This system is predicated on a multi-dimensional structure that organizes the vast litera...
    • 1.2.2 Quantitative Distribution of Articles
    • 1.2.3 Thematic Area
    • 1.2.4 Year of Publication
    • 1.2.5 Journal of publication
    • 1.2.6 Some Methodological Approaches used by the authors
  • 1.3 SUMMARY OF REVIEW FINDINGS
    • 1.3.1 Overview of the Fukushima Daiichi Nuclear Accident and Subsequent Radiological Impact
      • 1.3.1.1 Brief overview of Nuclear accident Pre Fukushima Daiichi
    • 1.3.2 Sequence of Events
    • The earthquake and the ensuing 14-meter-high tsunami overcame the plant's seawall. The power supply and backup generators were destroyed, causing a failure in the cooling systems of three of the plant's six reactors (Units 1, 2, and 3). Despite manual...
    • 1.3.3 Environmental Contamination
    • 1.3.4 Environmental Contamination
    • The released radionuclides contaminated the surrounding land, atmosphere, and marine environment. Airborne radionuclides were detected across the Northern Hemisphere, although concentrations outside Japan were generally below levels of concern for pub...
    • 1.3.5 Environmental Contamination
    • The released radionuclides contaminated the surrounding land, atmosphere, and marine environment. Airborne radionuclides were detected across the Northern Hemisphere, although concentrations outside Japan were generally below levels of concern for pub...
    • 1.3.6 Dose Assessment Challenges
    • 1.3.7 Health and Environmental Impact
    • 1.3.8 Impact on the Ocean
    • The release of contaminated water into the Pacific has necessitated ongoing monitoring to assess the impact on marine life and fisheries, which are vital to the local economy and food supply. Mitigating this impact has involved efforts to prevent furt...
    • 1.3.9 Long-Term Health Monitoring
    • As part of the post-accident response, long-term health monitoring programs have been established to assess the ongoing impact of the accident on public health, particularly the potential increase in cancer risk due to prolonged exposure to low-dose...
  • 1.4 Analysis of Dose Assessment Methodologies Used in Fukushima
  • The dose assessment methodologies utilized following the Fukushima Daiichi nuclear disaster were multifaceted, incorporating both direct measurement and modeling approaches to estimate radiation exposure to the public as shown in table 1.7. These meth...
  • 1.5 Summary Of Dose Monitoring Findings Post Fukushima
  • 1.6 Uncertainties Encountered in the Fukushima Dose Assessments
• 2 CHAPTER 2: COMPREHENSIVE REVIEW OF ARTICLES ON UNCERTAINTY DOSE ASSESSMENT POST-NPP ACCIDENT
  • 2.1 Systematic Classification of Uncertainty in Dose Assessment
  • This section provides a comprehensive classification of key findings on uncertainty in dose assessment revealed by a review of 24 scholarly articles. Selected for their focused inquiry into the ambiguity and variance of dose calculations, these papers...
    • 2.1.1 Reactor Type and Accident type
    • 2.1.2 Range of parameters
    • 2.1.3 Codes used
    • 2.1.4 Target parameter
    • 2.1.5 Journals of publication
    • 2.1.6 Year of publication
  • 2.2 Summary Of Uncertainty Dose Assessment Findings From Reviewed Documents
    • 2.2.1 Methodological Approaches to Uncertainty Analysis
      • 2.2.1.1 Sensitivity Analysis
      • 2.2.1.2 Wilks' Method
      • 2.2.1.3 Integrated Approach
    • 2.2.2 Application of Computational Codes
• 3 CHAPTER 3: EVALUATION OF UNCERTAINTY DOSE ASSESSMENT POST NUCLEAR POWER PLANT ACCIDENT
  • 3.1 Case studies and comparison of different NPP accident dose assessments.
    • 3.1.1 Fukushima Daiichi NPP Accident
    • 3.1.2 Case Studies Application where uncertainty analysis was applied.
• 4 CHAPTER 4: DISCUSSION
  • 4.1 Uncertainties in Dose Assessment
  • 4.2 Computational Codes For Uncertainty Dose Assessment
    • 4.2.1 JRODOS
    • 4.2.2 HOTSPOT
    • 4.2.3 RELAP
    • 4.2.4 MELCOR
    • 4.2.5 MACCS
  • 4.3 Uncertainties impact on dose assessment
  • 4.4 Dose Assessment under Different Emergency Scenarios
  • 4.5 Uncertainty in various protective measures.
  • 4.6 State of the art in uncertainty analysis for NPP accident dose assessments.
  • 4.7 Development Trends and Recommendations
  • 4.8 Recommendations for improving uncertainty management in dose assessment.
• CONCLUSION
• APPENDICES