The mobility of radionuclides in the subsurface environment is governed by a interaction of radioactivity characteristics and geochemical conditions with adsorption reactions playing a critical role. This study investigates the characteristics and mechanisms of radionuclides adsorption on site media in viewpoint of nuclear safety, particularly focusing on the potential effect of seawater infiltration in coastal site near nuclear power plant. Seawater intrusion alters the chemistry in groundwater, including parameters such as pH, redox potential, and ionic strength, thereby affecting the behavior of radionuclides. To assess the safety of site near nuclear power plant and the environmental implications of nuclide leakage, this research conducted various experiments to evaluate the behavior of radionuclides in the subsurface environment. High distribution coefficients (50-2,500 ml/g) were observed at 10 mg/L Co, with montmorillonite > hydrobiotite > illite > kaolinite. It decreased with competing cations (Ca2+) and was found to decrease significantly by 90% with a decrease in pH to 4. It is believed that the adsorption capacity of cationic radionuclides decreases significantly as the clay mineral surface becomes less negatively charged. For Cs, the distribution coefficient (180-560 ml/g) was higher for montmorillonite > hydrobiotite > illite > kaolinite. Compared to Co, it was found to be less influenced by pH and more influenced by competing cations. For Sr, the distribution coefficient (100-380 ml/g) was higher in the order of hydrobiotite > montmorillonite > illite > kaolinite. Compared to Cs, it was found to be less affected by pH and also less affected by the effect of competing cations compared to Cs. Seawater samples from Gampo and Uljin site near Nuclear Power Plant in Korea were analyzed to determine their chemical composition, which was subsequently used in adsorption experiments. Additionally, the seawater-infiltrated groundwater was synthesized in laboratory according to previous literature. The study focused on the adsorption and behavior of three key radionuclides such as cesium, strontium, and cobalt onto four low permeability media (clay minerals) such as kaolinite, illite, hydrobiotite, and montmorillonite known for their high adsorption capacity at a site of nuclear power plant. At concentrations of 5 and 10 mg/L, the adsorption coefficients followed the order of cobalt > cesium > strontium for each radionuclide. Notably, the distribution coefficient (Kd) values exhibited higher values in seawater-infiltrated groundwater environments compared to seawater with relatively high ionic strength. Cobalt exhibited a substantial adsorption coefficient, with a marked decrease in Kd values in seawater conditions due to elevated ionic strength. In contrast, cesium displayed less dependency on seawater compared to other radionuclides, suggesting distinct adsorption mechanisms, possibly involving fractured edge sites (FES) in clay. Strontium exhibited a significant reduction in adsorption in seawater compared to groundwater in all Kd sorption experiments. The adsorption data of cobalt, cesium, and strontium on clay minerals in contact with seawater and seawater-infiltrated solutions offer valuable insights for assessing radioactive contamination of groundwater beneath coastal site near nuclear power plant sites. This research provides a foundation for enhancing the safety assessment protocols of nuclear power plant sites, considering the potential effects of seawater infiltration on radionuclide behavior in the subsurface environment.

KORAD (Korea Radioactive Waste Agency, http://www.korad.or.kr) has stored slightly contaminated ascon (asphalt coated concrete mixture) that was introduced to Gyeongju repository about a decade ago waiting for a final disposal. It is believed to be mainly contaminated by radioisotope 137Cs due to impurities introduced from the outside during the ascon manufacturing process. We studied characteristics of the radioactive waste to see whether this material would be proper enough to be disposed in Gyeongju LILW repository or be other ways to reduce the disposal volume including self-disposal before its final disposal otherwise. KORAD looked into the properness of characteristics of ascon in terms of WAC (Waste Acceptance Criteria) documented by KORAD that includes general chemical and physical properties of asphalt, density, size of grains, content of organic material and possibility of existence of chelate materials that qualitatively limited to be disposed by the criteria. And other associated characteristics such as gas generation and bio degradation were also investigated. Based on the data obtained from the study, we proposed various plausible solutions in associated with operational and disposal safety and economic view points. This study will be used for KORAD’s decision on how to control and safely dispose the spent ascon within a reasonable time period. And also those experiences may be applied for other LILW issues that require treatment or conditioning of radioactive wastes in the future.

2022년부터 2023년까지 제주도내 키위 시설재배지를 대상으로 계절 초기 볼록총채벌레 발생 경향을 확인하 기 위해서 토양 표면의 잡초, 토양 표면 상단으로부터 60cm, 키위나무를 유인한 덕 상단 15cm에서 10일 간격으로 발생 조사하였다. 하우스 내부에서 발생하는 잡초 10종을 채집하여 조사한 결과, 갈퀴덩굴, 광대나물, 개불알풀, 별꽃, 뽀리뱅이, 황새냉이 6종에서 볼록총채벌레가 지속적으로 관찰되었다. 계절 초기 월동 성충의 비산시기를 확인하기 위해 토양 표면 60cm 위쪽에 설치한 황색 끈끈이트랩에서 2월 하순~3월 중순부터 볼록총채벌레의 발생을 확인하였다. 시설하우스 내부(덕 상단 15cm)와 외부(측장 높이)에 설치한 황색 끈끈이트랩을 비교해보면 시설 내·외부의 볼록총채벌레의 밀도가 증가하고 감소하는 시기가 유사하였다. 종합적인 고찰을 통하여, 발생 양상을 고려한 적절한 방제전략 수립이 요구된다.

The oriental fruit fly, Bactrocera dorsalis, is one of important agricultural pests that attack a wide range of fruits and vegetables. Adult female can cause direct damage by laying eggs under the skin of fruits and vegetables. The eggs hatch into larvae that feed in the decaying flesh of the agricultural crops. Damaged fruits and vegetables quickly become inedible or dropto the ground. We investigated the oviposition characteristics of B. dorsalis on twelve fruits and seven vegetables. B. dorsalis marked the oviposition places on every crop tested. B. dorsalis laid eggs into the fruits and vegetables except lemon and passionfruit. We examined the adult emergence from infested crops.

곤충병원성 선충인 Heterorhabditis. megidis(큰형광병원선충)는 참나무 군락지(광주광역시 소재) 사양토에 서 분리 동정되었고, 곤충병원성을 가지는 공생세균은 Photorhabdus temperata로 분리 동정되어 각각 GJ1-2로 명명하였다. H. megidis GJ1-2는 고추(녹광), 애호박(농우), 오이(백다다기), 참외(금싸라기), 토마토(베타티니) 유묘기 경엽처리와 배추(씨알천하일품), 상추(진청맛), 완두(청진주), 수박(삼복꿀), 무(서호) 유묘기 관주처리 에서 21일차까지 기준량과 배량에 대하여 약해(약해 판정기준결과: 0)가 나타나지 않았다, H. megidis GJ1-2는 배추 파밤나방에 대한 방제 효과는 이천시(경기도 소재)와 수원시(경기도 소재)의 시설재배 포장에서 각각 경엽 처리 3일차 71.8%. 73.9%, 7일차 86.2%, 84.6%로 나타났으며, 옥수수 열대거세미나방에 대한 방제 효과는 제주시 (제주특별자치도 소재)의 노지(미사질 양토)에서 경엽처리 7일차 82.6%로 나타났다. 그리고 H. megidis GJ1-2는 랫드를 이용한 급성경구와 급성경피 독성시험 반수치사농도(LD50) 값은 2,000 mg/kg B.W 초과로 IV급(저독성) 으로 구분되었고, 토끼를 이용한 피부와 안점막에 자극성이 없는 것으로 구분되었다. 그리고 담수어류(송사리) 에 대한 급성독성시험 반수치사농도(LD50) 값은 영향을 미치지 않는 기초시험농도 100 mg/L를 초과하였다.

This study aimed to develop a new eco-friendly control method of B. tabaci using a trap plant treated with systemic insecticide. Due to high preference, tobacco plant was selected as a trap plant among solanaceous plants. Out of all 6 systemic insecticides, dinotefuran WG showed the highest mortality (> 97.3 %) against B. tabaci. The concentrations of dinotefuran in tobacco leaves after systemic treatment showed the sharp increase in the pesticide from 2 hrs until 48 hrs (2 d) and steady increase over 35 d. The mortality of B. tabaci in tobacco leaves was about 80% at 9 hrs after treatment and over 90% at 1, 2, 3, 6, 9, and 35 d after treatment. The number of B. tabaci was counted every week after dinotefuran-treated tobacco pots were placed in the tomato greenhouse cultivation. The density of the insects with 3 tobacco plants was app. 75% lower than the control (w/o tobacco plant).

강원특별자치도 18개 시군을 대상으로 감나무와 콩에 발생하는 미국선녀벌레, 썩덩나무노린재, 담배거세미 나방의 발생을 조사하였다. 돌발해충인 미국선녀벌레는 약충기인 6월과 성충기인 10월에 발생조사를 진행하고 남방계해충인 담배거세미나방과 썩덩나무노린재는 7월과 9월 콩 재배기에 발생조사를 진행하였다. 미국선녀 벌레는 강원지역에 있는 감나무에서 발생을 확인할 수 없었고. 감나무 주변 기타 수목에서 가지당 평균 6.7마리 발생하였다. 담배거세미나방은 7월, 속초를 제외한 모든 시군에서 발생이 되었으며, 춘천, 횡성에서 트랩당 60마 리가 넘는 발생밀도를 보였으며, 원주, 강릉, 화천 등 에서는 트랩당 1마리로 낮은 발생밀도를 나타냈다. 썩덩나무 노린재는 7월 춘천, 속초, 홍천 등 7개 시군을 제외한 11개 시군에서 트랩에 포획되는 것을 확인하였으며, 화천에 서 트랩당 26마리로 최고발생밀도를 보였다.

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), which is native to tropical and subtropical regions of the Western Hemisphere is now annually arrives in Korea. In this study, we developed loop-mediated isothermal amplification (LAMP) assay, one of the main merits of which is a rapid identification of target species. Five among 11 FAW-specific loci tested successfully provided a consistent reaction when ten FAWs, which were collected from eight localities in four countries were tested, whereas the 13 non-target species were not amplified. To increase in-field applicability of the method all life stages, reaction time, and different periods after death was tested using the quick extracted DNA. Our FAW diagnostic protocol can be completed within 30 min, from the process of extracting genomic DNA from an egg or a 1st instar larva to species determination.

Land monitoring involves systematically understanding changes in land use, leveraging spatial information such as satellite imagery and aerial photographs. Recently, the integration of deep learning technologies, notably object detection and semantic segmentation, into land monitoring has spurred active research. This study developed a web service to facilitate such integrations, allowing users to analyze aerial and drone images using CNN models. The web service architecture comprises AI, WEB/WAS, and DB servers and employs three primary deep learning models: DeepLab V3, YOLO, and Rotated Mask R-CNN. Specifically, YOLO offers rapid detection capabilities, Rotated Mask R-CNN excels in detecting rotated objects, while DeepLab V3 provides pixel-wise image classification. The performance of these models fluctuates depending on the quantity and quality of the training data. Anticipated to be integrated into the LX Corporation's operational network and the Land-XI system, this service is expected to enhance the accuracy and efficiency of land monitoring.

The increasing number of technology transfers from public research institutes in Korea has led to a growing demand for patent recommendation platforms for SMEs. This is because selecting the right technology for commercialization is a critical factor in business success. This study developed a patent recommendation system that uses technology transfer data from the past 10 years to recommend patents that are suitable for SMEs. The system was developed in three stages. First, an item-based collaborative filtering system was developed to recommend patents based on the similarities between the patents that SMEs have previously transferred. Next, a content-based recommendation system based on TF-IDF was developed to analyze patent names and recommend patents with high similarity. Finally, a hybrid system was developed that combines the strengths of both recommendation systems. The experimental results showed that the hybrid system was able to recommend patents that were both similar and relevant to the SMEs' interests. This suggests that the system can be a valuable tool for SMEs that are looking to acquire new technologies.

It is difficult to distinguish the pure signal produced by an orbiting planetary companion around giant stars from other possible sources, such as stellar spots, pulsations, or certain activities. Since 2003, we have obtained radial (RV) data from evolved stars using the high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at the Bohyunsan Optical Astronomy Observatory (BOAO). Here, we report the results of RV variations in the binary star HD 135438. We found two significant periods: 494.98 d with eccentricity of 0.23 and 8494.1 d with eccentricity of 0.83. Considering orbital stability, it is impossible to have two companions in such close orbits with high eccentricity. To determine the nature of the changes in the RV variability, we analyzed indicators of stellar spot and stellar chromospheric activity to find that there are no signals related to the significant period of 494.98 d. However, we calculated the upper limits of rotation period of the rotational velocity and found this to be 478–536 d. One possible interpretation is that this may be closely related to the rotational modulation of an orbital inclination at 67–90 degrees. The other signal corresponding to the period of 8494.1 d is probably associated with a stellar companion orbiting the giant star. A Markov Chain Monte Carlo (MCMC) simulation considering a single companion indicates that HD 135438 system hosts a stellar companion with 0.57+0.017 −0.017 M⊙ with an orbital period of 8498 d.

The aim of this study was to determine the contamination of mycotoxins and the concentration of preservatives and antioxidants in commercial pet food. 106 pet foods were purchased from online in Korea. Mycotoxin analysis were performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and preservatives and antioxidants were analyzed by high performance liquid chromatography (HPLC). The contamination of the mycotoxins in all samples was proved to comply with the Korea legislation with regards to animal feed, the analyses revealed presence of aflatoxins, ochratoxin A, zearalenone and fumonisins, with values below 1.6 ㎍/㎏, 12.1 ㎍/㎏, 478.5 ㎍/㎏ and 1873.5 ㎍/㎏, respectively. Furthermore, the simultaneous presences of different mycotoxins were observed in most of positive samples. The levels of dehydroacetic acid (DHA), sorbic acid (SA) and benzoic acid (BA) were, respectively, with values below 0.24 g/㎏, 4.82 g/㎏ and 6.35 g/㎏. The concentrations of butylated hydroxy anisole (BHA) and butylated hydroxy toluene (BHT) were demonstrated to be acceptable, with values below 0.04 g/㎏, and 0.02 g/㎏. This indicated the need for further investigation into the potential risk deriving from chronic exposure to low doses of mycotoxins. Additionally, a co-contamination of mycotoxins which interact in synergic manner are more concern. As DHA that not accepted was detected and very high levels of SA were identified in samples, an upper limit for preservatives in pet foods should be established in pet foods. BHA and BHT were detected within the recommended levels for antioxidant content, so these are considered as safe.

This study aimed to investigate the effect of visual input enhancement (VIE) on the comprehension of reading texts and the learning of two grammatical forms: English relative clauses and articles. Individual learners’ working memory (WM) capacity was also tested to explore its impact on the effectiveness of VIE. A total of 48 Korean college learners of English were assigned into three groups: (a) relative group receiving VIE on relative clauses (b) article group receiving VIE on articles, and (c) a control group receiving no VIE. Results showed that VIE did not have any negative effect on the learners’ reading comprehension. Rather, it had positive effects on the learning of the two grammatical forms. According to the findings, VIE on relative clauses enhanced the learners’ receptive knowledge of the grammatical form, whereas VIE on articles enhanced the learners’ productive knowledge of the form. There was a potential link between the effectiveness of VIE and the learners’ working memory processing ability. Pedagogical implications are also discussed based on these findings.

Some consumer goods containing radioactive substances are in circulation and used in everyday life. In accordance with the Nuclear Safety Act, consumer goods with radioactivity are regulated. However, since most consumer goods distributed in Korea have no information that can confirm the amount of radiation, it is necessary to analyze the radiation for safety regulation. Among these consumer goods, GTLS (Gaseous Tritium Light Source) contains gaseous tritium (tritium, written as 3H or T), which is a radioactive material. The gaseous composition ratio in GTLS was analyzed using a precision gas mass spectrometer (Thermo Fisher, model MAT 271). As a result of GTLS analysis, the H2, HD or H3 +(T) or 3He, HT or D2 or He, DT, and T2, which correspond to the mass-to-charge ratio (m/z) 2 to 6 and the air components were detected. In addition, substances corresponding to m/z=24 and m/z=21 were also detected. These were compared with pure CH4 and those fragmentation patterns. The ratios of CT4 (m/z = 24) to CT3 (m/z = 21) and CH4 (m/z = 16) to CH3 (m/z = 15) were compared and they agree within the measurement uncertainty. We also performed additional experiments to separate the water component in the GTLS samples, considering the possibility that the m/z = 21 to m/z = 24 region is tritium compounds based on H2O. Despite the removal of the water components, peaks were detected at m/z=21 and m/z=24. Therefore, we confirmed that the component of m/z = 24 in the GTLS sample was CT4.

The mobility of radionuclides is largely determined by their radiological properties, geochemical conditions, and adsorption reactions, such as surface adsorption, chemical precipitation, and ion exchange. To evaluate the safety assessments of radionuclides in nuclear sites, it is essential to understand the behavior and mechanism of radionuclides onto soils. Since nuclear power plants are located in coastal areas, the chemical composition of groundwater can vary depending on the intrusion of seawater, altering the adsorption distribution coefficient (Kd) values of radionuclides. This study examines the impact of seawater on the Kd values of clay minerals for cesium (Cs) and strontium (Sr). The results of Cs+ adsorption experiments showed a broad range of Kd values from 36 to 1,820 mL/g at an initial concentration of 1 mg/L and a high sorption coefficient of 15-613 mL/g at an initial concentration of 10 mg/L. Montmorillonite, hydrobiotite, illite, and kaolinite were ranked in terms of their CEC values for Cs+ adsorption, with hydrobiotite having the highest adsorption at 1 mg/L. The results of Sr adsorption experiments showed a wide range of Kd values from 82 to 1,209 mL/g at an initial concentration of 1 mg/L and a lower adsorption coefficient of 6.68-344 mL/g at an initial concentration of 10 mg/L. Both Cs+ and Sr2+ demonstrated lower Kd values at higher initial concentrations. CEC of clays found to have a significant impact on Sr2+ Kd values. Ca2+ ions showed a significant impact on Sr2+ adsorption distribution coefficients, demonstrating the greater impact of seawater on Sr2+ compared to Cs+. These findings can inform future safety assessments of radionuclides in nuclear sites.

Air conditioning facilities in nuclear power plants use pre-filters, HEPA filters, activated carbon filters, and bag filters to remove radionuclides and other harmful substances in the atmosphere. Spent filters generate more than 100 drums per year per a nuclear power plant and are stored in temporary radioactive waste storage. Plasma torch melting technology is a method that can dramatically reduce volume by burning and melting combustible, non-flammable, and mixed wastes using plasma jet heat sources of 1,600°C or higher and arc Joule heat using electric energy, which is clean energy. KHNP CRI & KPS are developing and improving waste treatment technology using MW-class plasma torch melting facilities to stably treat and reduce the volume of radioactive waste. This study aims to develop an operation process to reduce the volume of bag filter waste generated from the air conditioning system of nuclear power plants using plasma torch melting technology, and to stably treat and dispose of it. It is expected to secure stability and reduce treatment costs of regularly generated filter waste treatment, and contribute to the export of radioactive waste treatment technology by upgrading plasma torch melting technology in the future.

After the Fukushima accident, significant amount of radioactively contaminated waste has been generated with 50~250 m3/day and stored in tanks of the Fukushima Daiichi nuclear power plant site. The contaminated water is treated by various treatment facility such as KURION, SARRY, Reverse Osmosis, and ALPS to remove 62 radioactive nuclides except H-3. For the contaminated water treatment process, massive secondary wastes such as sludge, spent adsorbent, and so on as by-product are being generated by the facilities. In Japan, to treat the secondary wastes, melting technologies such as GeoMelt, In-can vitrification and Cold Crucible Induction Melting vitrification are considered as a candidate technologies. In this study, the technologies were reviewed, and the advantage and disadvantage of each technology were evaluated as the candidate technologies for treatment of the secondary wastes.