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        검색결과 200

        3.
        2024.04 구독 인증기관·개인회원 무료
        Herbivorous insects can be exposed to soil contaminants via trophic transfer. To assess the effect of accumulated arsenate (As(V)) in host plants on aphids across generations, Myzus persicae were reared for several generations on pepper (Capsicum annuum) grown in soil treated with 0, 2, 4, and 6 mg of As(V) per kg. In the first generation, the body length of M. persicae significantly (p < 0.05) increased on As(V)-treated plants (μ = 1.29 mm) compared to untreated plants (μ = 1.21 mm). Aphids showed higher fecundity on plants treated with 2mg/kg of As(V) (15.3) compared to untreated ones (10.6), but it decreased again under the 4mg/kg (11.4) and 6mg/kg (11.2) treatments. When newborns were transferred to untreated plants after being reared on each treatment for two previous generations, they exhibited higher fecundity as their parents were treated with higher levels of As(V). While more research is needed to understand the unexpected beneficial effects, this study highlights the complex impacts of soil As(V) on aphid dynamics which span multiple generations.
        4.
        2024.04 구독 인증기관·개인회원 무료
        The family Gelechiidae (Lepidoptera: Gelechioidea) is known as one of the largest families in Microlepidoptera, encompassing about 600 genera and more than 5,000 described species worldwide. However, the genus Altenia Sattler, 1960 has been poorly studied in Korea, with only one known species. Here we introduce a new species, Altenia parascriptella sp. nov., from Korea, providing photos of adults and genitalia for both sexes, along with diagnostic characteristics.
        6.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Cadmium (Cd) is toxic heavy metal that accumulates in organisms after passing through their respiratory and digestive tracts. Although several studies have reported the toxic effects of Cd exposure on human health, its role in embryonic development during preimplantation stage remains unclear. We investigated the effects of Cd on porcine embryonic development and elucidated the mechanism. Methods: We cultured parthenogenetic embryos in media treated with 0, 20, 40, or 60 μM Cd for 6 days and evaluated the rates of cleavage and blastocyst formation. To investigate the mechanism of Cd toxicity, we examined intracellular reactive oxygen species (ROS) and glutathione (GSH) levels. Moreover, we examined mitochondrial content, membrane potential, and ROS. Results: Cleavage and blastocyst formation rates began to decrease significantly in the 40 μM Cd group compared with the control. During post-blastulation, development was significantly delayed in the Cd group. Cd exposure significantly decreased cell number and increased apoptosis rate compared with the control. Embryos exposed to Cd had significantly higher ROS and lower GSH levels, as well as lower expression of antioxidant enzymes, compared with the control. Moreover, embryos exposed to Cd exhibited a significant decrease in mitochondrial content, mitochondrial membrane potential, and expression of mitochondrial genes and an increase in mitochondrial ROS compared to the control. Conclusions: We demonstrated that Cd exposure impairs porcine embryonic development by inducing oxidative stress and mitochondrial dysfunction. Our findings provide insights into the toxicity of Cd exposure on mammalian embryonic development and highlight the importance of preventing Cd pollution.
        4,000원
        7.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        가는잎향유[Elsholtzia angustifolia (Loes.) Kitag.]는 화형 이 아름답고, 정유 특유의 향기가 좋아서 분화용 및 지피용 관 상식물로 수요가 증가하고 있고, 전초에는 약효가 있다고 알 려져 있다. 본 연구는 가는잎향유의 육묘에 미치는 플러그 트 레이 셀 사이즈, 파종립수, 차광정도, 추비농도 등의 영향을 구명하기 위하여 수행되었다. 연구결과, 플러그 트레이 셀 사 이즈는 용량이 증가할수록 유묘의 초장, 엽수, 마디수, 근장, 지상부 생체중이 유의적으로 증가하였다. 파종 립수는 2립 파 종 시 가장 효율적이었고, 파종량이 증가할수록 생육이 감소 하였다. 차광정도가 높아질수록 초장은 증가하였고, 경직경, 엽수, 마디수는 55% 차광에서 가장 우수하였다. 추비 처리 시 공시비료 1000배 처리구에서 생육이 가장 양호하였다. 따라 서 가는잎향유의 육묘 시 162셀 트레이에 원예상토를 채운 다음 셀 당 2립 파종한 후 55% 차광막이 설치된 육묘상에서 공시비료 1000배로 엽면시비하는 것이 가장 효과적인 것으로 생각된다.
        4,000원
        8.
        2024.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Hydraulic conductivity is a critical design parameter for buffers in high-level radioactive waste repositories. Most employed prediction models for hydraulic conductivity are limited to various types of bentonites, the main material of the buffer, and the associated temperature conditions. This study proposes the utilization of a novel integrated prediction model. The model is derived through theoretical and regression analyses and is applied to all types of compacted bentonites when the relationship between hydraulic conductivity and dry density for each compacted bentonite is known. The proposed model incorporates parameters such as permeability ratio, dynamic viscosity, and temperature coefficient to enable accurate prediction of hydraulic conductivity with temperature. Based on the results obtained, the values are in good agreement with the measured values for the selected bentonites, demonstrating the effectiveness of the proposed model. These results contribute to the analysis of the hydraulic behavior of the buffer with temperature during periods of high-level radioactive waste deposition.
        4,000원
        9.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The objectives of this paper are: (1) to conduct the thermal analyses of the disposal cell using COMSOL Multiphysics; (2) to determine whether the design of the disposal cell satisfies the thermal design requirement; and (3) to evaluate the effect of design modifications on the temperature of the disposal cell. Specifically, the analysis incorporated a heterogeneous model of 236 fuel rod heat sources of spent nuclear fuel (SNF) to improve the reality of the modeling. In the reference case, the design, featuring 8 m between deposition holes and 30 m between deposition tunnels for 40 years of the SNF cooling time, did not meet the design requirement. For the first modified case, the designs with 9 m and 10 m between the deposition holes for the cooling time of 40 years and five spacings for 50 and 60 years were found to meet the requirement. For the second modified case, the designs with 35 m and 40 m between the deposition tunnels for 40 years, 25 m to 40 m for 50 years and five spacings for 60 years also met the requirement. This study contributes to the advancement of the thermal analysis technique of a disposal cell.
        4,500원
        10.
        2023.11 구독 인증기관·개인회원 무료
        As the decommissioning of domestic nuclear power plants (Gori Unit 1 and Wolseong Unit 1) becomes more visible, many research projects are being conducted to safely and economically decommissioning of domestic nuclear power plants (NPPs). After permanent shutdown, decommissioning of NNPs proceeds through decontamination, cutting of main equipment, waste disposal and site restoration stages. And various technologies are applied at each stage. In particular, remote cutting of neutron induced structures (RV, RVI, etc.) is a technology used in developed countries in the cutting stage, and remote cutting has been evaluated as a core technology for minimizing workers’ radiation exposure. Generally, remote cutting technologies are divided into mechanical/thermal/electrical cutting. Among various thermal cutting technologies, plasma arc cutting (PAC) is more economical and easily to remote control than other cutting technologies, and is also effective in cutting STS304 plates. PAC is a thermal cutting technology that melts the base material at the cutting area with a plasma arc heat source and removes melted material by blowing it out with cutting gas. The cutting quality depends on the stand-off distance and power (current), material thickness, cutting speed, etc., while double arcing will occur if the cutting conditions are not suitable. A monitoring system that can confirm double arcing during remote cutting is necessary because double arcing can reduce cutting quality, increase secondary waste (increase kerf and aerosol), and cause non-cutting. In this study, we used an ultrahigh-speed camera equipped with a band-pass filter to capture clear arc shapes, and measured voltage waveforms with a data acquisition system. We studied a monitoring method that can confirm the occurrence of double arcing by synchronizing the obtained arc shape and voltage waveform, and the effects of double arcing on the STS304 plates. The results of this study are expected to be helpful in the development of the remote cutting process using plasma arc cutting when decommissioning of domestic NPPs.
        11.
        2023.11 구독 인증기관·개인회원 무료
        Nuclear facilities present the important task related to the migration and retention of radioactive contaminants such as cesium (Cs), strontium (Sr), and cobalt (Co) for unexpected events in various environmental conditions. The distribution coefficient (Kd) is important factor for understanding these contaminants mobility, influenced by environmental variables. This study focusses the prediction of Kd values for radionuclides within solid phase groups through the application of machine-learning models trained on experimental data and open source data from Japan atomic energy agency. Three machine-learning models, such as the convolutional neural network, artificial neural network, and random forest, were trained for prediction model of the distribution coefficient (Kd). Fourteen input variables drawn from the database and experimental data, including parameters such as initial concentration, solid-phase characteristics, and solution conditions, served as the basis for model training. To enhance model performance, these variables underwent preprocessing steps involving normalization and log transformation. The performances of the models were evaluated using the coefficient of determination. These results showed that the environmental media, initial radionuclide concentration, solid phase properties, and solution conditions were significant variables for Kd prediction. These models accurately predict Kd values for different environmental conditions and can assess the environmental risk by analyzing the behavior of radionuclides in solid phase groups. The results of this study can improve safety analyses and longterm risk assessments related to waste disposal and prevent potential hazards and sources of contamination in the surrounding environment.
        12.
        2023.11 구독 인증기관·개인회원 무료
        The nuclear facilities at Korea Atomic Energy Research Institute (KAERI) have generated a variety of organic liquid radwaste and radiation levels are also varied. At KAERI, the organic liquid radwaste has been stored at Radioactive Waste Treatment Facility (RWTF) temporarily due to the absence of the recognized treatment technique while inorganic liquid radwaste can be treated by evaporation, bituminization, and solar evaporation process. The organic liquid radioactive waste such as spent oil, cutting oil, acetone, ethanol, etc. was generated from the nuclear facilities at KAERI. Among the organic liquid radioactive wastes, spent oil is particularly significant. According to the nuclear safety act, radioactive waste can be cleared by incineration and landfilling if it meets the criteria of less than 10 μSv/h for individual dose and 1 person – Sv/y for collective dose. Dose assessment was performed on some organic liquid radioactive waste with a very low possibility of radioactive contamination stored in RWTF at KAERI. As a result, it was confirmed that some wastes met the regulatory clearance standards. Based on this, it was approved by the regulatory body, and this became the first case in Korea and KAERI for permission for regulatory clearance of organic liquid radioactive waste by landfill after incineration.
        13.
        2023.11 구독 인증기관·개인회원 무료
        The thermal evaluations for the conceptual design of the deep geological repository considering the improved modeling of the spent fuel decay heat were conducted using COMSOL Multiphysics computational program. The maximum temperature at the surface of a disposal canister for the technical design requirement should not exceed 100°C. However, the peak temperature at the canister surface should not exceed 95°C considering the safety margin of 5°C due to several uncertainties. All thermal evaluations were based on the time-dependent simulation from the emplacement time of the canister to 100,000 years later. In particular, the heat source condition was set to the decay heat rate and axial decay heat profile of the PLUS7 fuel with 4.0wt% U-235 and 45 GWD/MTU. The thermal properties of the granitic rock in South Korea were applied to the host rock region. For the reference design case, the cooling time of the SNF was set to 40 years, the distance between the deposition holes 8 meters and that between the deposition tunnels 30 meters. However, the peak temperature at the canister surface at 10 years was 95.979°C greater than 95°C. This design did not meet the thermal safety requirement and needed to be modified. For the first modified case, when the distance between the deposition tunnels was set to 30 meters, three cooling time cases of 40, 50 and 60 years and five distances of 6, 7, 8, 9 and 10 meters between the deposition holes were considered. The design with the distances of 9 and 10 meters between the deposition holes for the cooling time of 40 years and all five distances for 50 and 60 years were less than 95°C. For the second modified case, when the distance between the deposition holes was set to 8 meters, three cooling time cases of 40, 50 and 60 years and five distances of 20, 25, 30, 35 and 40 meters between the deposition tunnels were considered. The design with the distances of 35 and 40 meters between the deposition tunnels for the cooling time of 40 years, the distances of 25, 30, 35 and 40 meters for 50 years and all five distances for 60 years were less than 95°C. As a result, the peak temperature at the canister surface decreased as the cooling time and the distance between the deposition holes and the tunnels increased.
        14.
        2023.10 구독 인증기관·개인회원 무료
        꿀벌에 대한 중요성이 인식되고 도시양봉의 수요가 증가하는 가운데 도시양봉에 최적화된 벌통을 제작하였 다. 꿀벌과 도시양봉에 대한 설문를 진행한 결과, 분봉으로 인한 민원이 도시양봉을 하는 데 가장 큰 저해요소로 꼽혔다. 이에 분봉을 방지하여 시민과 어우러질 수 있으며 친환경적인 벌통을 제작하는 데 초점을 맞췄다. 분봉을 방지하기 위해서는 여왕벌의 이탈을 감지하는 자성 센서와 벌들이 분봉을 하고자 하는 욕구인 분봉열을 감지하 는 온도 센서를 설치하여 효율을 파악하였다. 더불어 최근 이상기후로 인한 잦은 폭우와 고열을 견디기 위하여 밀랍을 이용한 벌통 코팅을 진행하였다. 벌통의 바닥에는 트레이를 서랍처럼 분리 설치할 수 있도록 함으로써 무더운 기온에서는 손쉽게 트레이를 빼서 환기에 중점을 두고, 그 외의 조건에서는 트레이를 끼워둠으로써 바닥 에 떨어진 꿀벌의 사체를 주기적으로 수거하여 유전자 분석을 함으로써 꿀벌의 건강 상태를 점검할 수 있도록 하였다. 꿀벌이 해당 벌통으로 인하여 스트레스를 받는지 꿀벌의 주요 스트레스 마커 유전자의 상대적 발현량을 조사한 결과, 일반적인 벌통에서의 발현량 수준과 큰 차이가 없는 것을 확인할 수 있었다. 이처럼 새로이 디자인된 벌통을 이용한다면 이상기후에서도 도시양봉을 하는 데 기여할 수 있을 것으로 기대된다.
        17.
        2023.07 구독 인증기관·개인회원 무료
        Digital fashion represents key technologies for the online environment, and it has been used as a new marketing strategy for the fashion industry. As consumer digital experience has been diversified, research on the effect on consumer attitudes and behavior toward digital fashion needs to be investigated. This study examines the effect of visual tactile and presence of VR fashion stores on consumer attitude via consumer surveys. Visual tactile and presence positively influence consumer experience which includes fantasy, feeling, and fun. In addition, these three experiences positively affect consumer attitude. The moderating effect of cyber motion sickness is discussed. Academic and practical implications for digital fashion are provided.
        18.
        2023.07 구독 인증기관·개인회원 무료
        Digital technologies that travel between the real and virtual worlds are rapidly adopted by many fashion brands for building virtual fashion spaces. This study aims to investigate the consumer experience of the components of the virtual fashion show and their effect on virtual fashion space, perceived benefits, perceived risk, and behavioral intention in the immersive fashion virtual space. The stimulus for this study was selected as the Prada virtual reality (VR) fashion show which is one of the most active in the VR field. The influence of perceived virtual fashion space and the moderating effect of VR sickness and fashion innovativeness are discussed. This study provides implications about consumer perception and behavior using VR in the context of virtual fashion space for researchers and practitioners.
        19.
        2023.05 구독 인증기관·개인회원 무료
        As the importance of radioactive waste management has emerged, quality assurance management of radioactive waste has been legally mandated and the Korea Radioactive Waste Agency (KORAD) established the “Waste Acceptance Criteria for the 1st Phase Disposal Facility of the Wolsong Lowand Intermediate-Level Waste Disposal Center (WAC)”, the detailed guideline for radioactive waste acceptance. Accordingly, the Korea Atomic Energy Research Institute (KAERI) introduced a radioactive waste quality assurance management system and developed detailed procedures for performing the waste packaging and characterization methods suggested in the WAC. In this study, we reviewed the radioactive waste characterization method established by the KAERI to meet the WAC presented by the KORAD. In the WAC, the characterization items for the disposal of radioactive waste were divided into six major categories (general requirements, solidification and immobilization requirements, radiological, physical, chemical, and biological requirements), and each subcategories are shown in detail under the major classification. In order to satisfy the characterization criteria for each detailed item, KAERI divided the procedure into a characterization item performed during the packaging process of radioactive waste, a separate test item, and a characterization item performed after the packaging was completed. Based on the KAERI’s radioactive waste packaging procedure, the procedure for characterization of the above items is summarized as follows. First, during the radioactive waste packaging process, the characterization corresponding to the general requirements (waste type) is performed, such as checking the classification status of the contents and checking whether there are substances unsuitable for disposal, etc. Also, characterization corresponding to the physical requirements is performed by checking the void fraction in waste package and visual confirmation of particulate matter, substances containg free water, ect. In addition, chemical and biological requirements can be characterized by visually confirming that no hazardous chemicals (explosive, flammable, gaseous substances, perishables, infectious substances, etc.) are included during the packaging process, and by taking pictures at each packaging steps. Items for characterization using separate test samples include radiological, physical, and chemical requirements. The detailed items include identification of radionuclide and radioactivity concentration, particulate matter identification test, free water and chelate content measurement tests, etc. Characterization items performing after the packaging is completed include general requirements such as measuring the weight and height of packages and radiological requirements such as measurements of surface dose rate and contamination, etc. All of the above procedures are proceduralized and managed in the radioactive waste quality assurance procedure, and a report including the characterization results is prepared and submitted when requesting acceptance of radioactive waste. The characterization of KAERI’s radioactive waste has been systematically established and progressed under the quality assurance system. In the future, we plan to supplement various items that require further improvement, and through this, we can expect to improve the reliability of radioactive waste management and activate the final disposal of KAERI’s radioactive waste.
        20.
        2023.05 구독 인증기관·개인회원 무료
        Transport packages have been developed to transport the decommissioning waste from the nuclear power plant. The packages are classified with Type IP-2 package. The IAEA requirements for Type IP-2 packages include that a free drop test should be performed for normal conditions of transport. In this study, drop tests of the packages were performed to prove the structural integrity and to verify the reliability of the analysis results by comparing the test and analysis results. Half-scale models were used for the drop tests and drop position was considered as 0.3 m oblique drop on packages weighing more than 15 tons. The strain and impact acceleration data were obtained to verify the reliability of the analysis results. Before and after the drop tests, radiation shielding tests were performed to confirm that the dose rate increase was within 20% at the external surface of the package. Also, measurement of bolt torque, and visual inspection were performed to confirm the loss or dispersion of the radioactive contents. After each drop test, slight deformations occurred in some packages. However, there was no loss of pretension in the lid bolts and the shielding thickness was not reduced for metal shields. In the package with concrete shield, the surface dose rate did not increase and there was no cracks or damage to the concrete. Therefore, the transport packages met the legal requirements (no more than a 20% increase of radiation level and no loss or dispersion of radioactive contents). Safety verifications were performed using the measured strain and acceleration data from the test, and the appropriate conservatism for the analysis results and the validity of the analysis model were confirmed. Therefore, it was found that the structural integrity of the packages was maintained under the drop test conditions. The results of this study were used as design data of the transport packages, and the packages will be used in the NPP decommissioning project in the future.
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