There is a large amount of radioactive waste in waste storage in the Korea Atomic Energy Research Institute. Some of the radioactive waste was generated during the dismantling process due to Korea Research Reactor 1&2 and it accounts for 20% of the total waste. Radioactive waste must be reduced by appropriate disposal methods to secure storage space and to reduce disposal costs. Research Reactor wastes include wastes that are below the acceptable criteria for selfdisposal and non-contaminated wastes, so they can be treated as wastes subject to self-disposal through contamination analysis and reclassification. In order to deregulation radioactive waste, it is necessary to meet the self-disposal standards stipulated in the Domestic Nuclear Act and the treatment standards of the Waste Management Act. The main factors of deregulation are surface contaminant, radionuclide activity and dose assessment. To confirm the contamination of waste, surface contaminant and gamma nuclide analysis were performed. After homogenizing the waste sample, it was placed in 1 L Mariinelli beaker. When collecting waste samples, 1 kg per 200 kg of waste was collected. The concentrations of the major radionuclides Co-60, Cs-134, Cs-137, Eu-152, and Eu-154 were analyzed using HPGe detector. To evaluate radiation dose, various computational programs were used. A dose assessment was performed with the analyzed nuclide concentration. The concentrations of representative nuclides satisfied the deregulation acceptance criteria and the results of the dose assessment corresponding to self-disposal method was also satisfied. Based on this results, KAERI submitted the report on waste self-disposal plan to obtain approval. After final approval, Research Reactor waste is to be incinerated and incineration ash is to be buried in the designated place. Some metallic waste has been recycled. In this study, the suitability of deregulation for self-disposal was confirmed through the evaluation of the surface contaminant analysis, radionuclide concentration analysis and dose assessment.

A survey of plant-parasitic nematodes (PPNs) was carried out in medicinal crop cultivated fields from July to August in 2023. Three-leaf ladybell, Adenophora triphylla var. japonica is a highly valued medicinal plant that is used to treat or prevent bronchitis, cough, cancer, and obesity in Korea. A. triphylla plants with small root-galls were observed in a field of Yeongju Agricultural Technology Center, which were identified as a root-knot nematode. Additional morphological and molecular analyses studies were performed and identified as Meloidogyne hapla, Northern root-knot nematode. Population densities of M. hapla ranged from 20~30 nematodes per 100 cm3 of soil. M. hapla was detected at lower densities in soil compared to other infected host crops, but there are concerns about damage to M. hapla since A. triphylla is cultivated for more than two years once planted. Our results indicate that A. triphylla roots damage by M. hapla were identifed, it is necessary to prepare control methods such as registration of applicable nematicides and crop rotation.

In this study, we focus on the improvement of data quality transmitted from a weather buoy that guides a route of ships. The buoy has an Internet-of-Thing (IoT) including sensors to collect meteorological data and the buoy’s status, and it also has a wireless communication device to send them to the central database in a ground control center and ships nearby. The time interval of data collected by the sensor is irregular, and fault data is often detected. Therefore, this study provides a framework to improve data quality using machine learning models. The normal data pattern is trained by machine learning models, and the trained models detect the fault data from the collected data set of the sensor and adjust them. For determining fault data, interquartile range (IQR) removes the value outside the outlier, and an NGBoost algorithm removes the data above the upper bound and below the lower bound. The removed data is interpolated using NGBoost or long-short term memory (LSTM) algorithm. The performance of the suggested process is evaluated by actual weather buoy data from Korea to improve the quality of ‘AIR_TEMPERATURE’ data by using other data from the same buoy. The performance of our proposed framework has been validated through computational experiments based on real-world data, confirming its suitability for practical applications in real- world scenarios.

Recently, small and medium-sized manufacturing companies have shown increased interest in and participation in smart factories in order to survive in market competition. However, many SMEs build smart factories without a systematic review or preparation, which leads to them not being able to use them properly. This study considers the main reason for the low utilization rate of smart factories to be a lack of sufficient reflection of user requirements. Therefore, a method and procedure for deriving the priority of smart factory requirement functions and operating performance indicators based on QFD is proposed as a solution to this issue.

Since radon was detected in mattresses of famous bed furniture brands in 2018, the nuclear safety and security commission (NSSC) announced the radiation safety management act in April 2021 to protect the public health and environment. This act stipulates the safety management of radiation that can be encountered in the natural environment such as the notification of radioactivity concentration of source materials, process by-products, the installation and operation of radioactive monitors. In this study, a model was established to predict radioactive exposure dose from radioactive materials such as radon and uranium detected in consumer products such as bed mattresses, pillows, shower, bracelets and masks in order to identify major radioactive substances that largely affect the exposure dose. A period of seven years from 2014 to 2020 was investigated for the source materials and exposure doses of consumer products containing naturally occurring radioactive materials (NORMs). We analyzed these using machine learning models such as classification and regression tree (CART), Random Forest and TreeNet. Index development and verification were performed to evaluate the predictive performance of the models. Overall, predictive performance was highest when Random Forest or TreeNet was used for each consumer product. Thoron had a great influence on the internal exposure dose of bedding, clothing and mats. Uranium had a great influence on the internal exposure dose of other consumer products except whetstones. When the number of data is very small or the missing value rate is high, it is difficult to expect accurate predictive performance even with machine learning techniques. If we significantly reduce the missing value rate of data or use the limit of detection value instead of missing values, we can build a model with more accurate predictive performance.

The chelating agent and cellulose generated during the operating and decommissioning of a NPP’s form organic complexing compounds. That is accelerate the migration of radionuclide and have a bad influence of LILW disposal site. In this study, the GoldSim (RT module) program was used for the effects of radionuclide migration by organic complex compounds as described above. A scenario was derived for evaluation, and a conceptual design (Concept Art) of the GoldSim model was performed. 1) Derivation of the scenario. For the scenario, we selected a groundwater flow scenario in which groundwater flows in and radionuclides flow out after a lapse of time after the operation of the LILW disposal site in Gyeongju is closed. The inflowing groundwater comes into contact with radioactive waste and the radionuclides dissolve. The dissolved nuclides move past the drum and out of the disposal vessel due to the advection phenomenon. Radionuclides spilled from the disposal vessel pass through the silo internal filler (crushed stone) and reach the engineering barrier concrete. Radionuclides from degraded concrete are scenarios that move along the flow of groundwater to the near and far. 2) Radionuclide migration concept design. The radionuclide movement section was largely designed with Inner (Inside the silo), Near and Far. (A) Inner (Inside the silo) This section is where radionuclides move from the radiation source to the engineering barrier (silo). The detailed migration path was designed to allow radioactive nuclides to flow out and move to waste drums, solidified matrix of indrum, disposal vessel fillers, disposal vessels, silo fillers (crushed stones), and engineered barriers (concrete). The LILW disposal site in Gyeongju has a total of 6 silos. Each of the 6 silos was modeled and designed in consideration of the structural information and positional impact. (B) Near & Far. In generally design, the near is form source term to engineered barrier and far is beyond the engineered barrier. In this study, the near and far designed by radionuclide in the section from the beyond the engineering barrier (silo) to the sea through the groundwater flow through the natural rock. Especially in the case of near, the design was made by applying the position of the natural rock sampling drill hole.

Long-term non-surgical contraceptive methods for cats, especially community cats, are of global interest for cost-effective and humane reasons. This study aimed to investigate the effectiveness of a gonadotropin-releasing hormone (GnRH)-based vaccine for immunocontraception and to confirm its safety in intact female cats. Recombinant Salmonella typhimurium flagellin fljB (STF2)-GnRH protein was expressed in Escherichia coli. We divided female cats into vehicle control group (n = 4) and two experimental groups (100 μg injection group [n = 7] and 1000 μg injection group [n=7]), and immunized them twice intramuscularly (0.2 mL/cat at zero week and 4 weeks later into the other leg). Breeding trials started on day 120. All control cats (n = 4/4), 71% of the 100 μg injection group (n = 5/7), and 57% of the 1000 μg injection group (n = 4/7) became pregnant within 203 days after the introduction of male cats. The 1000 μg injection group had significantly a longer median time to conception following treatment (166 days) than the control (17 days, p < 0.05). Average litter size was significantly lower in the 1000 μg GnRH-vaccinated cats (2.8 ± 0.7) than in the control cats (4.5 ± 0.5, p < 0.05). Injection site reactions were not observed in any cat. The E. coli-expressed STF2-GnRH vaccine did not provide contraception in a sufficient proportion of the cats. However, it might be effective to suppress fertility through infertility vaccines before inducing permanent infertility through the trap-neuter-return.

In this study, we investigated the effects of cooling rate during storage on spring kimchi cabbage from an economic perspective. For long-term storage, kimchi cabbage (KC) should be maintained at a low temperature immediately after harvest; however, a sudden change in temperature during storage may lead to chilling injury in KC. The optimal cooling rate is important for the long-term storage of KC. To identify the optimal cooling rate, KC was cooled at different cooling rates (1oC, 2oC, 4oC, 6oC, 8oC, and 24 oC/day), and then stored at 1oC for 90 days. Thereafter, weight, trimming, total loss, pH, free sugar content, and total bacterial count changes were measured. Spring KC stored at the cooling rate of 6 oC/day presented a lower total loss and better sensory properties than KC stored at other cooling rates; thus, 6 oC/day is an appropriate cooling rate for long-term storage of KC.

Feral cats are widely considered to be leading the potential impacts on public health. This study aimed to provide estimates of vital data for feral cats relating Trap-Neuter-Return (TNR) to establish strategies effectively to manage feral cats in Pyeongtaek. Thus, this study focused on estimating feral cat population in Pyeongtaek and conducted a comparative analysis of the data for feral cats in Seoul (2013). The number of feral cats was estimated from 23,069 to 26,655 in Pyeongtaek, 2019. In relation to human population, when comparing the number of feral cats of Pyeongtaek and Seoul, it ranged from 4.57% to 5.28%, and from 1.97% to 2.55% respectively. This showed that Pyeongtaek was higher than Seoul. Fewer kittens were found in high-density areas, which the TNR project is believed to be generally effective in controlling the number of feral cats. In conclusion, in urban and rural complexes such as Pyeongtaek City, the number of feral cats compared to the population was higher than that of Seoul City, and the TNR program is believed to be somewhat effective in controlling the number of feral cats. When implementing TNR, it is necessary periodically to investigate the population and reflect them in policymaking.