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        검색결과 1,202

        181.
        2022.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The acoustic emission (AE) is proposed as a feasible method for the real-time monitoring of the structural damage evolution in concrete materials that are typically used in the storage of nuclear wastes. However, the characteristics of AE signals emitted from concrete structures subjected to various environmental conditions are poorly identified. Therefore, this study examines the AE characteristics of the concrete structures during uniaxial compression, where the storage temperature and immersion conditions of the concrete specimens varied from 15℃ to 75℃ and from completely dry to water-immersion, respectively. Compared with the dry specimens, the water-immersed specimens exhibited significantly reduced uniaxial compressive strengths by approximately 26%, total AE energy by approximately 90%, and max RA value by approximately 70%. As the treatment temperature increased, the strength and AE parameters, such as AE count, AE energy, and RA value, of the dry specimens increased; however, the temperature effect was only minimal for the immersed specimens. This study suggests that the AE technique can capture the mechanical damage evolution of concrete materials, but their AE characteristics can vary with respect to the storage conditions.
        4,000원
        182.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Bovine mammary epithelial (MAC-T) cells are commonly used to study mammary gland development and mastitis. Lipopolysaccharide is a major bacterial cell membrane component that can induce inflammation. Autophagy is an important regulatory mechanism participating in the elimination of invading pathogens. In this study, we evaluated the mechanism underlying bacterial mastitis and mammary cell death following lipopolysaccharide treatment. After 24 h of 50 μg/mL lipopolysaccharide treatment, a significant decrease in the proliferation rate of MAC-T cells was observed. However, no changes were observed upon treatment of MAC-T cells with 10 μg/mL of lipopolysaccharide for up to 48 h. Thus, upon lipopolysaccharide treatment, MAC-T cells exhibit dose-dependent effects of growth inhibition at 10 μg/mL and death at 50 μg/mL. Treatment of MAC-T cells with 50 μg/mL lipopolysaccharide also induced the expression of autophagy-related genes ATG3, ATG5, ATG10, ATG12, MAP1LC3B, GABARAP-L2, and BECN1. The autophagy-related LC3A/B protein was also expressed in a dose-dependent manner upon lipopolysaccharide treatment. Based on these results, we suggest that a high dose of bacterial infection induces mammary epithelial cell death related to autophagy signals.
        4,000원
        183.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aster 속에 속하는 자생식물로는 눈갯쑥부쟁이, 개쑥부쟁이, 쑥부쟁이, 벌개미취, 참취 등이 있는데, 대부분 식용 또는 관상용 으로 많이 활용되고 있다. 특히 눈갯쑥부쟁이는 제주 한라산(표 고 1,200~1500m근처)에서 자생하는 한반도 특산식물로써, 다른 Aster 속과 다르게 포복성을 가지고 있고 개체당 소화의 수가 많아 관상가치가 매우 뛰어나다. 또한 파종 당해년에도 개화가 가능하기 때문에 유망한 관상식물 자원이라 할 수 있다. 본 연구 에서는, 한반도 특산 눈갯쑥부쟁이의 유전자원 보존 및 대량번 식을 위한 기초자료를 확보하고자 종자의 발아특성 및 휴면유형 을 분류하였다. 눈갯쑥부쟁이 종자는 형태적으로 완전하게 발달 된 배를 가지고 있고, 배양 72시간 내에 145%의 수분을 흡수하 였다. 4가지 온도조건(4°C, 15/6°C, 20/10°C, 25/15°C)에 배양한 결과, 광조건에서는 각각 67.0%, 58.9%, 62.2%, 71.6% 발아하였 고, 암조건에서는 각각 79.4%, 65.9%, 65.9%, 49.1% 발아하였 다. 저온층적처리(4°C) 실험 결과, 최종 발아율에는 큰 차이가 없었으나, 층적처리 기간 동안에도 발아하는 특성을 관찰하였 다. GA3처리 후 25/15°C에 배양한 결과, 0, 10, 100, 1000mg·L-1 처리에서 각각 57.9%, 68.3%, 74.9%, 63.9%의 발아율을 보였 다. 15/6°C에 배양한 경우에는 각각 78.3%, 62.8%, 72.2%, 55.9% 발아하였다. 본 연구에서는 위 실험들을 통하여, 약 80% 정도는 non-dormant 종자로, 나머지 약 20%는 생리적 휴면 (physiological dormancy)을 가지고 있는 것으로 판단되었다.
        4,000원
        184.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        털부처꽃(Lythrum salicaria L.)은 전국에 분포하는 다년생 초본식물로 척박하고 습한 지역을 포함한 다양한 환경에서 잘 자라는 것으로 알려져 있다. 따라서 하천변, 척박지에서 정원 용, 화훼용 및 관상용 식물로 이용이 가능하다. 본 연구는 털 부처꽃의 적정 육묘 조건(토양종류, 플러그 트레이 셀 크기,파종립수, 액비농도 및 차광)을 조사하였다. 대조구(원예상토) 에서 재배된 유묘의 생육이 가장 우수하였다. 반면 피트모스 와 펄라이트의 혼합용토는 육묘기간이 지속되면서 생육수치 가 감소하는 경향을 나타냈다. 셀 크기는 용적이 가장 큰 162 셀에서 재배된 유묘의 생육이 우수하였으나, 200셀과 288셀에 서 자란 묘도 건강했다. 한편 유묘의 결주발생을 고려하면 셀 당 2립을 파종하는 것이 적합하였다. 액비 처리는 유묘의 생 육을 촉진하였다. 특히 Hyponex 1000배는 초장, 줄기직경, 엽수, 마디수, 근장, 지상부 생체중 및 지하부 생체중을 증가 시켰다. 또한 유묘의 생육은 55% 차광 하에서 우수하였다. 따 라서 털부처꽃의 가장 효과적인 생육조건은 원예상토가 충진 된 288셀 플러그 트레이에 셀 당 2립을 파종하고 Hyponex 1000배를 시비하면서 55% 차광 하에서 재배하는 것이었다.
        4,000원
        185.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        컴퓨터 성능의 발전으로 빅데이터의 효율적인 사용이 가능해지면서, 심층 학습(deep learning)은 다양한 의료 분야에 활용할 수 있는 핵심적인 인공지능(artificial intelligence, AI) 기법으로 각광받고 있다. 이에 본 종설은 뇌종양 진단과 치료에 사용되는 자기공명영상(magnetic resonance imaging, MRI)의 심층 학습 기법을 소개하고자 하였다. 먼저 국내 AI의 의료 분야 도입의 동향을 분석하고, 이를 바탕으로 MRI를 활용한 뇌종양의 진단과 치료에 적용할 수 있는 심층 학습 기법과 그 결과들을 기술하였다. 뇌종양 진단과 치료 시, 심층 학습을 이용한 최근 사례는 영상 분류, 영상 품질 개선, 영상 분할로 나타났으며, 질병의 진단과 치료에 적용할 수 있는 객관적이고 높은 성능 수치를 나타내면서 그 유용성을 확인 할 수 있었다. 종합하자면, 심층 학습은 질병의 진단과 치료에 적용할 수 있는 유용한 지표이며, AI 역량을 지닌 의료진의 지도하에 점진적인 도입이 이뤄진다면 질병의 진단과 치료에 큰 도움을 주는 훌륭한 소프트웨어로 활용될 것으로 여겨진다. 본 종설이 심층 학습을 이해할 때 많은 도움이 되길 바라며, 향후 관련 연구를 수행할 때 가이드라인으로 활용될 것을 기대 한다.
        4,800원
        186.
        2022.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서 Periphyllus acerihabitans를 국내에서 최초로 보고한다. 이 종의 분포지역, 기주식물, 무시성충의 형태학적 정보와 분류키를 제공 하였다.
        4,000원
        187.
        2022.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Thermodynamically, TRUOx, REOx, and SrOx can be chlorinated using ammonium chloride (NH4Cl) as a chlorinating agent, whereas uranium oxides (U3O8 and UO2) remain in the oxide form. In the preliminary experiments of this study, U3O8 and CeO2 are reacted separately with NH4Cl at 623 K in a sealed reactor. CeO2 is highly reactive with NH4Cl and becomes chlorinated into CeCl3. The chlorination yield ranges from 96% to 100%. By contrast, U3O8 remains as UO2 even after chlorination. We produced U/REOx- and U/SrOx-simulated fuels to understand the chlorination characteristics of the oxide compounds. Each simulated fuel is chlorinated with NH4Cl, and the products are dissolved in LiCl-KCl salt to separate the oxide compounds from the chloride salt. The oxide compounds precipitate at the bottom. The precipitate and salt phases are sampled and analyzed via X-ray diffraction, scanning electron microscope-energy dispersive spectroscopy, and inductively coupled plasma-optical emission spectroscopy. The analysis results indicate that REOx and SrOx can be easily chlorinated from the simulated fuels; however, only a few of U oxide phases is chlorinated, particularly from the U/SrOx-simulated fuels.
        4,800원
        188.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The canine parvovirus (CPV) causes clinical signs, such as severe enteritis, dehydration, diarrhea, vomiting, leukopenia, and hair loss, which may lead to death. Vaccination is still the most important approach, as no specific treatment exists to prevent CPV. Monoclonal antibodies are valuable tools to study the pathogenic mechanisms of CPV and develop effective diagnostic reagents and pharmaceuticals. In this study, two monoclonal antibodies (MAbs) against CPV-2a were obtained through hybridoma technology by fusing myeloma cells and B cells from the spleens of mice immunized with CPV type 2a (CPV-2a). Two MAbs (CPV-330 and CPV-620) were studied on the reactivity of vaccine (CPV-2a) and field strains (CPV-new 2a, -2b, and -2c) by indirect immunofluorescence (IFA), hemagglutination inhibition test (HI), virus neutralization test (VN), and inhibition of virus growth test. Two MAbs showed similar antibody titers for HI and VN. On the other hand, CPV-330 inhibited the viral replication in Crandell-Rees Feline Kidney (CRFK) cells better than CPV-620. These CPV MAbs may provide valuable biological reagents to study the CPV pathogenic mechanisms and work as therapeutic antibodies.
        4,000원
        189.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 의료분야에서 정확한 환자 확인(patient identification)을 위한 의료생체인식기술(medical biometrics)을 소개하고 자 한다. 첫째, 생체인식기술(biometrics)에 대한 정의, 분류 및 종류와 같은 기본 정보다. 둘째, 생체신호 (biological signal)와 의료영상(medical imaging)을 활용한 의료생체인식기술의 종류와 최근 연구에 관한 정보를 기술했 다. 마지막으로 의료 환경에서 적용되는 생체인식기술의 종류와 사례와 함께 의료 환경의 현주소를 언급했다. 환자확인이 라는 궁극적인 목적을 가진 의료생체인식기술은 의료 현장에 점진적으로 도입되리라 생각한다. 본 연구는 본 연구가 정확 한 환자확인을 위한 의료생체인식기술을 이해하고 연구방향에 도움이 되는 기초 자료로 활용될 것으로 사료된다.
        4,500원
        192.
        2022.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To develop quality-improved muffins, the influence of the partial replacement of wheat flour with lemon balm powder (LBP) on their quality characteristics was analyzed. Studies were carried out to examine the supplementation of different percentages of LBP (2%, 4%, 6%, and 8%) on the quality characteristics of LBP muffins. The incorporation of LBP significantly affected the physicochemical parameters of muffins. Such incorporation at different levels significantly decreased pH, moisture content, baking loss, hardness, and color parameters, including L*, a*, and b* values of muffins (p<0.05). No significant effect of LBP substitution was found in height changes (p>0.05). Finally, the consumer acceptance test indicated that the highest levels of LBP incorporation (i.e., 8%) had a considerably adverse effect on consumer preferences in all attributes. In contrast, muffins with moderate levels of LBP (4%) showed a good and satisfactory sensorial acceptance in general. Thus, LBP was successfully employed in muffins, improving quality and broadening its potential applications in other bakery products.
        4,000원
        193.
        2022.05 구독 인증기관·개인회원 무료
        The type of accidents associated with the operation of a melting facility for radioactive metal waste is assumed to only marginally differ from those associated with similar activities in the conventional metal casting industry or the current waste melting facility. However, the radiological consequences from a mishap or a technical failure differ widely. Three critical and at the same time possible accidents were identified: (1) activity release due to vapor explosion, (2) activity release due to ladle breakthrough, (3) consequences of failure in the hot-cell or furnace chamber not possible to remedy using remote equipment.
        194.
        2022.05 구독 인증기관·개인회원 무료
        In this work, we introduce a 100 kW class mobile plasma melting system designed for non-combustible radioactive wastes treatment. To ensure mobility, the designed system consists of two 24-ft commercial containers, each in charge of the plasma utilities and melting process. In the container for plasma utilities, a 100 kW class DC power supply is installed together with a chiller and gas supply system whereas the container for melting process has a transferred type arc melter as well as off-gas treatment system consisting of a heat exchanger, filtrations, scrubber and NOx removal system. As a heat source for a transferred type arc melter, we adopted a hollow electrode plasma torch with reverse polarity discharge structure. Detailed design for a 100 kW class mobile plasma melting system will be presented together with the main specifications of the components. In addition, the basic performance data of the melting system is also presented and discussed.
        195.
        2022.05 구독 인증기관·개인회원 무료
        As the plan for the nuclear dismantlement due to the permanent shutdown of Kori-1 and Wolseong- 1 nuclear power plants has been concretized, a “movable radionuclide analysis system” is being developed that can quickly and accurately analyze large amounts of radioactive waste generated on the sites during dismantling. This system has various advantages from the perspective of strict regulations on the radioactive waste movement and social acceptability, such as preventing unexpected accidents while moving on the national highway or expressway, reducing various documents and immediate response to dismantling plans. Currently the system is being developed to be equipped with previously developed sample pretreatment and radioactivity measuring equipment and automated volatile and nonvolatile nuclide separation equipments, but to ensure mobile stability, it needs to analyze factors and establish stability standards. In the KS Q ISO/IEC 17025:2017 standard, the requirements for “facilities and environmental conditions” are a very important factor in building reliability for consumers as part of the quality guarantee for this facility. In order to meet the requirements, the technical standards of various test equipment to be installed in this facility were investigated. The physical, chemical, and radiological hazards that could affect the safety of the equipment and workers in the process of moving the equipment between nuclear power plants or between nuclear dismantling sites were derived from vibrations, rapid changes in temperature and humidity, and the spread of contamination from radioactive waste samples. Therefore, the scope of application of the law, which is the basis for securing stability during movement, was classified into two situations: movement from facility manufacturer to installation site (non-contaminated) and movement from primary to secondary use (contaminated). And in order to investigate the Nuclear Safety Act, enforcement ordinances, and radiation safety management, and to establish standards for packaging and transportation of radioactive materials, the results of transportation tests and transport details were compared and analyzed. Finally, the air suspension systems and the automatic temperature and humidity control devices were analyzed to establish standards for securing stability against the vibration and the sharp changes in the temperature and humidity, and countermeasures such as accident measures in accordance with the Enforcement Decree of the Nuclear Safety Act were also investigated.
        196.
        2022.05 구독 인증기관·개인회원 무료
        With the development of the nuclear industry and the increase in the use of radioactive materials, the generation of radioactive waste is increasing. As the generation of radioactive waste increases, the occurrence of related safety accidents is also increasing, and it is necessary to develop a radioactive waste monitoring technology to prevent such accidents in advance and efficiently manage radioactive waste. In Information and Communication Technology (ICT), various ICT technologies such as Internet of Things (IoT), Augmented Reality (AR), and Virtual Reality (VR) that can help with the safety management of these radioactive wastes are being developed. In this study, a radioactive waste monitoring technology was developed using ICT technology, such as management of the entire cycle history of waste using Quick Response (QR) codes, and development of AR visualization technology for small packages of radioactive waste. In addition, by using IoT technology to collect desired data from sensors and store the results, after the waste drum is loaded in the waste storage, a technology was developed to track and monitor the history and movement of the waste drum from repackaging to transfer to the storage. The data required for monitoring the radioactive waste drum includes location information, whether the drum is open or closed, temperature and humidity, etc. To collect this information, a drum monitoring technology was built with a 2.4 G wireless router, an anchor constituting a virtual zone, a tag to be mounted on the drum container, and a WNT server that collects sensor data. The network tool provided by WirePas was used for network configuration, and the status of gateways and nodes can be monitored by interworking with the WNT server. The configured IoT sensor technology were tested in a waste storage environment. Four anchors were installed and linked to the network to match the virtual zone and the real storage zone, and it was confirmed whether the movement of the tag was recorded on the network while moving the tag including the IoT sensor for analyzing location information. Based on these research results, it can contribute to the safety management of radioactive waste and establishment of Waste Acceptance Criteria (WCP) by and managing the history and monitoring the waste in the entire cycle from repackaging to disposal.
        197.
        2022.05 구독 인증기관·개인회원 무료
        Dry head end process is developing for pyro-processing at KAERI (Korea Atomic Energy Research Institute). Dry processes, which include disassembly, mechanical decladding, vol-oxidation, blending, compaction, and sintering shall be performed in advance as the head-end process of pyroprocessing. An important goal of the head-end process is the fabrication of a proper feed material for the subsequent electrolytic reduction process. In the vol-oxidation process, the pellet type-SFs are pulverized by an oxidation under an air-blowing condition, and some volatile fission products are removed from the produced powders by using an air flow. After blending, the U3O8 powders are moved to a compactor of compaction process to obtain U3O8 porous pellets. In the fine powders removal system connected with compactor, for the improved performance of oxide reduction process coupled to dry head-end process, the removal/recovery system for fine powders potentially attached to the surface of oxide reduction raw material was developed and applied to the removal of fine powders from green pellets fabricated in dry head-end process. The removal efficiency of fine powders was also verified using porous U3O8 pellets in the fine powders removal system.
        198.
        2022.05 구독 인증기관·개인회원 무료
        In this study, for thermal neutron absorption, an aluminum metal composite in which B4C particles were uniformly dispersed was prepared using stirring casting and hot rolling processes. The microstructure, thermal neutron absorption rate, mechanical properties and dispersibility of the reinforcement of the prepared B4C/Al composite were analyzed. The composite in which the 40 μm sized B4C particles were uniformly dispersed increased the tensile strength as the volume ratio of the reinforcement increased.
        199.
        2022.05 구독 인증기관·개인회원 무료
        Molten salt immersion technique has been tested with several Sr oxides, SrZrO3, SrMoO4 and U2SrOy, and MgCl2 based molten salts for the Sr nuclide separation. Reaction time, temperature, and salt composition were varied to effectively separate Sr in chloride forms. ICP-OES, XRD, and SEM analysis were conducted for the conversion efficiency and structure and morphology analysis. It is confirmed that all experiments of SrZrO3 with MgCl2 at 800°C for reaction time 5, 10, 20 hours showed higher conversion efficiency than 99% and in LiCl-KCl-MgCl2 and NaCl-MgCl2 molten salts at 500°C or 600°C, conversion efficiency higher than 97% was obtained. SrMoO4 in MgCl2 immersion experiments for 10 hours showed higher conversion efficiency than 99% when the molar ratio of salt/oxide powder is 7. U2SrOy was also tested with MgCl2 molten salt at 800°C and higher efficiency than 99% and mainly MgUO4 were produced as a reaction product.
        200.
        2022.05 구독 인증기관·개인회원 무료
        To estimate the removal efficiency of TRU and rare earth elements in an oxide spent fuel, basic dissolution experiments were performed for the reaction of rare earth elements from the prepared simfuel with chlorination reagents in LiCl-KCl molten salt. Based on the literature survey, NH4Cl, UCl3, and ZrCl4 were selected as chlorination reagent. CeO2 and Gd2O3 powders were mixed with uranium oxide as a representative material of rare earth elements. Simfuel pellets were prepared through molding and sintering processes, and mechanically pulverized to a powder form. The experiments for the reaction of the simfuel powder and chlorination reagents were carried out in a LiCl-KCl molten salt at 500°C. To observe the dissolution behavior of rare earth elements, molten salt samples were collected before and after the reactions, and concentration analysis was performed using ICP. After the reaction completed, the remaining oxide was washed with water and separated from the molten salt, and XRD was used for structural analysis. As a result of salt concentration analysis, the dissolution performance of rare earth elements was confirmed in the reaction experiments of all chlorination reagents. In an experiment using NH4Cl and ZrCl4, the uranium concentration in the molten salt was also measured. In other words, it seemed that not only rare elements but also uranium oxide, which is a main component of simfuel, was dissolved. Therefore, it is thought that the dissolution of rare earth elements is also possible due to the collapse of the uranium oxide structure of the solid powder and the reaction with the oxide of rare earth elements exposed to molten salt. As a result of analyzing the concentration changes of Simfuel before and after each reaction, there was little loss of uranium and rare earth elements (Ce/Gd) in the NH4Cl experiment, but a significant amount of rare earth elements were found to be reduced in the UCl3 experiment, and a large amount of rare earth elements were reduced in the ZrCl4 reaction.