To achieve permanent disposal of radioactive waste drums, the radionuclides analysis process is essential. A variety of waste types are generated through the operation of nuclear facilities, with dry active waste (DAW) being the most abundant. To perform radionuclides analysis, sample pretreatment technology is required to transform solid samples into solutions. In this study, we developed a dry ashing-microwave digestion method and secured the reliability of the analysis results through a validity evaluation. Additionally, we conducted a comparative analysis of the radioactivity of 94Nb nuclides with and without the chemical separation process, which reduced the minimum detectable activity (MDA) level by more than 65-fold for a certain sample.

Recently, BNS (Best System) developed a system for evaluation and classification of soil and concrete wastes generated from nuclear power plant decommissioning. It is composed of various modules for container loading, weight measurement, contamination evaluation, waste classification, stacking, storage and control. The contamination evaluation module of the system has two sub modules. One is for quick measurement with NaI (Tl) detector and the other is for accurate measurement with HPGe detector. The container used at the system for wastes handling has capacity of 100 kg and made of stainless steel. According to the measurement result of Co-60 and Cs-137, the waste is classified as waste for disposal or waste for clearance. Performance of the system was demonstrated using RM (Reference Material) radiation source. This year, necessity of system improvement was suggested due to revised operation requirements. So, the system should show throughput of more than 1 ton/hr and Minimum Detectable Activity (MDA) of less than 0.01 Bq/g (1/10 of criteria for regulatory clearance) for Co-60 and Cs-137. And soil waste become main target of the system. For this, the container used for soil waste handling should have capacity of 200 kg. As a result, material for the container need to be changed from stainless steel to plastic or FRP (Fiber Reinforced Plastics). And large area detector should be introduced to the system to enhance processing speed of the system. Additionally, container storage rack and conveyor system should be modified to handle 200 kg capacity container. Finally, moving path of the container will be redesigned for enhanced throughput of the system. In this paper, concept development of the system was suggested and based on that, system development will be followed.

Physical protection education was legislated by the Ministry of Education, Science and Technology (MEST) in November 2010. KINAC (Korea Institute of Nuclear Nonproliferation and Control) was designated as the exclusive institution for physical protection education and training by MEST in October 2011, and it has since functioned as the sole institution responsible for this critical aspect of nuclear security education in the country. Over the past decade, KINAC has undertaken a variety of training initiatives aimed at enhancing the capabilities of nuclear operators’ physical protection personnel. Furthermore, it has consistently pursued annual curriculum revisions based on insights gleaned from surveys and workshops. In conventional curriculum assessments, general surveys often rely on Likert scale or short-answer questions as primary indicators, mainly due to their ease of data processing. Descriptive questions, while capable of capturing diverse opinions, have historically been relegated to a secondary role owing to the inherent challenges associated with data analysis. While physical protection education has made concerted efforts to solicit diverse opinions through descriptive questions, difficulties in organizing and leveraging this valuable data have resulted in it primarily serving as reference material. This study introduces a novel approach by employing ChatGPT, a chatbot, to conduct a comprehensive analysis of the descriptive questions from the physical protection education survey administered in the first half of 2023. The primary objective is to formulate a robust plan for curriculum enhancement based on a wide spectrum of opinions. Following the completion of physical protection training by 2,014 individuals in the first half of 2023, a survey was distributed, yielding an impressive response rate of 95.7% with 1,927 respondents. Chatbots were harnessed to extract major keywords and perform frequency analyses on approximately 360 responses to descriptive questions in the survey. The analysis revealed that certain keywords emerged with notable frequency, in the following order: “drone” (mentioned 51 times), “access management” (mentioned 28 times), “inspection and search” (mentioned 27 times), and “cybersecurity” (mentioned 20 times). Further analysis of these major keywords and related content revealed a consensus among trainees that there is a pressing need to incorporate topics addressing drone threats and responses, as well as strategies to fortify access management into the curriculum. This study underscores the potential to harness standardized data analysis techniques to synthesize and integrate trainees’ subjective opinions, thereby providing a solid foundation for the refinement of the curriculum.

The KINAC resident inspectors are responsible for conducting on-site regulatory and intergovernmental support tasks related to safeguards, physical protection, and cybersecurity in each NSSC regional office. In nuclear material accounting and control, resident inspectors primarily perform tasks such as national inspections and technical support for IAEA inspections. However, with the increasing cases of non-compliance with the advance notification procedure by operators, there is a growing need for improvement in the role of resident inspectors in on-site regulation. In response to this situation, the safeguards division in KINAC has analyzed and improved the on-site check procedures of resident inspectors at LWR facilities. The existing procedure outlines the process where resident inspectors receive the advance notification documents submitted by operators and utilize them as a reference for conducting weekly checks during the overhaul period when IAEA surveillance cameras are installed. Additionally, according to the attached forms specified in the procedure, resident inspectors are required to submit the check results report to the director of the safeguards division in KINAC every week and to the NSSC every month. The inspection items include checking the execution and changes of advance notification, verifying unnotified matters, discussing other issues, assessing the integrity of things such as the operational status of IAEA surveillance equipment, and so on. On April 13-14, 2023, the Safeguards division organized a two-day resident inspector’s work-sharing workshop to discuss improvements in the on-site check procedures of resident inspectors at LWR facilities. During the workshop, a comparison and analysis were conducted between the existing procedures and actual on-site activities. Unnecessary tasks such as advance notification document reception and monthly reporting were eliminated, and the focus was shifted towards emphasizing essential tasks. The opinions of resident inspectors were taken into account to derive directions for improvement. The existing procedure was applicable only during Overhaul periods for resident inspectors. It has been improved by removing this limitation, allowing its use during routine times. Furthermore, the procedure has been enhanced by clarifying its purpose, scope, users, and definitions of terms and specifying responsibilities and authorities. Unnecessary terminology has been eliminated. Remarkably, the definition of advance notification has been detailed, and the reporting of check results has been simplified through weekly task reporting. The Safeguards division in KINAC has strived to enhance the efficiency and simplification of on-site regulatory activities for resident inspectors at LWR facilities by improving their on-site check procedures. These improvement activities are expected to aid resident inspectors in effectively performing a wide range of tasks, including safeguards, physical protection, cybersecurity, and government support. In the future, it will be possible to continue refining the on-site check procedures by sharing the results of using the procedure in meetings and gathering various opinions from resident inspectors.

Combat-armored vehicles were equipped with an automatic-fire-extinguishing system to ensure the safety of the crew and vehicle from fires on the vehicle. When a fire was occurred, the automatic-fire-extinguishing system automatically detects the fire through sensors and detection lines, sprays a fire extinguisher, and notifies the crew visually and audibly. Recently, there had been cases of automatic-fire-extinguishing systems malfunction on combat-armored vehicles. In this study, in order to resolve the automatic-fire-extinguisher's malfunction phenomenon, ground noise and inter-circuit noise generated from the fire detection line were identified, and the resistance connected on the circuit was revised to remove noise. As a result of resistance revision, the noises was eliminated and the electromotive force difference between input circuits was made constant, thereby improving the malfunction of the automatic-fire-extinguishing system. By applying the result, it was confirmed that the control device sensed a temperature similar to the actual temperature on actual vehicles, and it was confirmed that the automatic-fire-extinguishing system's malfunction phenomenon was not founded in the field vehicles after then.

Raman distributed temperature sensor can be used as temperature instruments as well as monitoring abnormalities in next-generation nuclear systems. Since noise reduction and Measuring Frequency enhancement are required, integration time adjustment has been mainly used so far. In this study, a new data processing method using Moving Average Filter was analyzed to see if noise reduction and Measuring Frequency could be reduced, and improvement measures were suggested.

This paper is a study on the malfunction that occurred during the power supply logic of the Gunner Display Device during Mortar Functional Firing under low temperature conditions. As a result of the phenomenon reproduction test and its analysis, the cause of the malfunction of the Gunner Display Device was Glitch, which occurred in the process of converting the image signal, and the improved software was applied to the Gunner's Display System by ignoring some of the image signal conversion process that causes Glitch. The improved Gunner Display Device passed the validity test and applied the improvement to the mortars. As a result of this study, several suggestions for power supply and control logic were proposed. It is expected that this study will be used as a reference in the future design of similar weapons systems.

During the initial construction of Won buddhism, the sound absorbing material and diffusion material were used in the interior of the Won buddhism, so the sound performance at each buddhism could not be secured above a certain level, and even in the case of the Won buddhism Bukil dharma hall, the reverberation and volume of the sound generated inside the sanctum was too loud, and since the establishment of the buddhism continued to be dissatisfied, the improvement of the acoustic performance was very urgent. From this perspective, this study measured acoustic performance of the Bukil dharma hall before remodeling, determined the acoustic defects and status, and used acoustic simulation to present three plans for improving acoustic performance. Taking economic feasibility, construction, and construction duration into account, remodeling was performed on the basis of Plan 1 and post-remodeling acoustic performance was measured for comparative analysis of acoustic performance between before and after the improvement. The results of study, before and after sound performance improvement sound pressure level (SPL500Hz) was 71.9dB at 79.4dB , the weighted sound level (SPLdB(A)) was 79.7dB(A) at 89.4dB(A), reverberation time (RT500Hz) was 1.12sec at 1.49sec, early decay time (EDT500Hz) was 1.39sec at 1.63sec, definition (D50,500Hz) was 34.9% at 32.3%, clarity (C80.500Hz) was 1.0dB at –0.4dB, and RASTI was 60.0%(“Good”) at 51.3%(“Fair”) was evaluated. Therefore, the Bukil dharma hall was after remodeling, neither definition(D50) improved notably but excessive volume and reverberation and sound mixing almost disappeared and acoustic performance improved so much that many different events and services could be held.

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×102 mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

PURPOSES : The purpose of this study was to improve the performance of concrete pavements by decreasing measurement deviations using an Internet of Things (IoT)-based air content measurement device. METHODS : We calculated the properties of concrete which varied according to the air content. For a low measurement deviation, the concrete pavement performed according to the design standard. To confirm the difference in the performance of the concrete pavement for various air contents, we verified the change in the relative dynamic modulus according to the number of freeze–thaw cycles for each value of the air content. In addition, we analyzed the number of durability cracks according to the freeze–thaw cycles in the field. RESULTS : We confirmed that IoT-based measurement equipment improved the performance of pavements without changing their mixing designs or specifications. We confirmed that the performance of concrete pavements changed even with variations in air content within the range of quality standards. Using IoT-based air content management, we confirmed the reduction in concrete pavement durability cracks without changing the mixing design. CONCLUSIONS : We confirmed that IoT-based air-content management improved pavement performance. The feasibility of extending this concept to manage other concrete properties such as the chloride content should be acknowledged. Future research will require laboratory tests to understand the variation in concrete properties with varying air contents and to consider diverse load conditions.