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        검색결과 184

        1.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Since rice is the main food in Korea, there are no regulations on corn milling yet. Corn is known as one of the world's top three food crops along with wheat and rice, and it is known that 3.5 billion people worldwide use corn for food. In addition, corn mills are not developed or sold in Korea, but the use of corn mills is increasing significantly in many countries in Southeast Asia. In the Philippines, as Korea's rice mill import increases, Korea's KAMICO (Korea Agricultural Machinery Industry Cooperative) and domestic company A agreed to develop a corn mill jointly with PHilMech, an organization affiliated with the Philippine Ministry of Agriculture. However, research on corn milling was very insignificant, so the development was carried out based on the technology of Korea's rice mill. Rice milling is performed by peeling off the skin of rice and producing brown or white rice, so it is carried out by removing the skin and cutting the skin. On the other hand, in the corn mill, the skin of the corn is peeled, pulverized and selected to produce main products suitable for edible use. Therefore, in order to develop a corn mill, processes such as peeling, transfer, grinding, sorting, and by-product separation are required, and suitable parts must be developed. In addition, the performance must be gradually improved through experiments in which corn is repeatedly milled. The Philippines produces 7.98 million tons/year of corn, which is about 100 times that of Korea, and is mostly consumed as a staple food. This is about 10% of the total crop production in the Philippines. In addition, the main cultivation complexes of corn are the mountainous regions of Tarlac or Pangasinan, and the produced corn is 72.4% of the so-called yellow corn called Arabel and Sarangani, and the remaining 27.6% are known as white corn. In this study, it was intended to produce grains of 2.5 mm or less suitable for food for yellow corn and to develop a corn mill for 200 kg per hour. Detailed conditions for development are stipulated as more than 55% of the main product recovery rate, more than 31% of the by-product recovery rate, less than 5% of the raw material loss rate, and more than 80% of the embryo dislocation rate. In this study, to achieve this, the overall process of the corn mill was developed, and the optimal conditions for the corn mill were obtained through the development of parts and empirical tests to improve performance. In addition, it was intended to achieve the development goal by evaluating and analyzing the performance of each part so that it did not conflict.
        4,800원
        2.
        2023.11 구독 인증기관·개인회원 무료
        KEPCO KPS is the contractor for the full system decontamination (FSD) of Kori Unit 1 and under preparation such as modification, lay out for equipment installation, setting up tie-in/out point for chemical injection and way to pressurize the system, of its successful performance. In this research, KPS introduced how KPS has designed and prepared for the FSD project and how will the chemical decontamination process be implemented. As described in the previous research, chemical decontamination process is planned to be conducted for three cycles and each cycle is consisted of oxidation, reduction, decomposition, and purification. Oxidation and reduction process were conducted at 90°C. Chemical decomposition and purification process were conducted at 40°C due to the damage of IX by the heat. If the decontamination result does not meet the target DF and the dose rate, additional cycle can be conducted. Expected volume of process water for FSD is 200 m3. Three systems have been designated as decontamination targets: reactor coolant system (RCS), residual heat removal system (RHRS), chemical volume control system (CVCS). For the steady flow rate, existed plant equipment such as reactor coolant pump (RCP) will be operated and modifications on some components will be conducted. Due to the limited space for installation, decontamination equipment and other resources are distributed to three different places. KPS designed the layout of equipment installed inside the containment vessel. The layout contains the information of shielding for highly radiated equipment such as IX and filter skid.
        3.
        2023.11 구독 인증기관·개인회원 무료
        Activated carbon (AC) is used for filtering organic and radioactive particles, in liquid and ventilation systems, respectively. Spent ACs (SACs) are stored till decaying to clearance level before disposal, but some SACs are found to contain C-14, a radioactive isotopes 5,730 years halflife, at a concentration greater than clearance level concentration, 1 Bq/g. However, without waste acceptance criteria (WAC) regarding SACs, SACs are not delivered for disposal at current situation. Therefore, this paper aims to perform a preliminary disposal safety examination to provide fundamental data to establish WAC regarding SACs SACs are inorganic ash composed mostly of carbon (~88%) with few other elements (S, H, O, etc.). Some of these SACs produced from NPPs are found to contain C-14 at concentration up to very-low level waste (VLLW) criteria, and few up to low-level waste (LLW) criteria. As SACs are in form of bead or pellets, dispersion may become a concern, thus requiring conditioning to be indispersible, and considering VLL soils can be disposed by packaging into soft-bags, VLL SACs can also be disposed in the same way, provided SACs are dried to meet free water requirement. But, further analysis is required to evaluate radioactive inventory before disposal. Disposability of SACs is examined based on domestic WAC’s requirement on physical and chemical characteristics. Firstly, particulate regulation would be satisfied, as commonly used ACs in filters are in size greater than 0.3 mm, which is greater than regulated particle size of 0.2 mm and below. Secondly, chelating content regulation would be satisfied, as SACs do not contain chelating chemicals. Also, cellulose, which is known to produce chelating agent (ISA), would be degraded and removed as ACs are produced by pyrolysis at 1,000°C, while thermal degradation of cellulose occurs around 350~600°C. Thirdly, ignitability regulation would be satisfied because as per 40 CFR 261.21, ignitable material is defined with ignition point below 60°C, but SACs has ignition point above 350°C. Lastly, gas generation regulation would be satisfied, as SACs being inorganic, they would be targeted for biological degradation, which is one of the main mechanism of gas generation. Therefore, SACs would be suitable to be disposed at domestic repositories, provided they are securely packaged. Further analysis would be required before disposal to determine detailed radioactive inventories and chemical contents, which also would be used to produce fundamental data to establish WAC.
        4.
        2023.11 구독 인증기관·개인회원 무료
        Domestic waste acceptance criteria (WAC) require flowable or homogeneous wastes, such as spent resin, concentrated waste, and sludge, etc., to be solidified regardless of radiation level, to provide structural integrity to prevent collapse of repository, and prevent leaching. Therefore, verylow level (VLL) spent resin (SR) would also require to be solidified. However, such disposal would be too conservative, considering IAEA standards do not require robust containment and shielding of VLL wastes. To prevent unnecessary cost and exposure to workers, current WAC advisable to be amended, thus this paper aims to provide modified regulation based on reviewed engineering background of solidification requirement. According to NRC report, SR is classified as wet-solid waste, which is defined as a solid waste produced from liquid system, thus containing free-liquid within the waste. NRC requires liquid wastes to be solidified regardless of radiation level to prevent free liquid from being disposed, which could cause rapid release of radionuclides. Furthermore, considering class A waste does not require structural integrity, unlike class B and C wastes, dewatering would be an enough measure for solidification. This is supported by the cases of Palo Verde and Diablo Canyon nuclear power plants, whose wet-solid wastes, such as concentrated wastes and sludge, are disposed by packaging into steel boxes after dewatering or incineration. Therefore, dewatering VLL spent resin and packaging them into structural secure packaging could satisfy solidification goal. Another goal of solidification is to provide structural support, which was considered to prevent collapse of soil covers in landfills or trenches. However, providing structural support via solidification agent (ex. Cement) would be unnecessary in domestic 2nd phase repository. As the domestic 2nd phase repository is cementitious structure, which is backfilled with cement upon closure, the repository itself already has enough structural integrity to prevent collapse. Goldsim simulation was run to evaluate radiation impact by VLL SR, with and without solidification, by modelling solidified wastes with simple leaching, and unsolidified wastes with instant release. Both simulations showed negligible impact on radiation exposure, meaning that solidifying VLL SR to delay leaching would be irrational. Therefore, dewatering VLL SR and packaging it into a secure drum (ex. Steel drum) could achieve solidification goals described in NRC reports and provide enough safety to be disposed into domestic repositories. In future, the studied backgrounds in this paper should be considered to modify current WAC to achieve efficient waste management.
        5.
        2023.11 구독 인증기관·개인회원 무료
        EU taxonomy requires to solve problems for safe management of radioactive waste and disposal of spent fuel, which is a precondition for growing demand for nuclear power plant. Currently, Korea manages about 18,000 tons of high-level radioactive waste at temporary storage facilities in nuclear power plant sites, but such temporary storage facilities are expected to become saturated sequentially from 2031. Therefore, it is necessary to secure a permanent disposal facility to safely treat high-level radioactive waste. In accordance with the second basic plan for high-level radioactive waste management in 2021, it is necessary to establish requirements for regulatory compliance for the site selection and site acquisition, investigation and evaluation, and construction for the establishment of a deep geological disposal facility. In this study, we analyzed the regulatory policies and cases of leading foreign countries related to deep geological disposal facilities for high-level radioactive waste disposal waste such as IAEA, USA, Sweden, and Finland using data analysis methodology. To analyze a large amount of textbased document data, text mining is applied as a major technology and a verification standard that secures validity and safety based on the regulatory laws described so far is developed to establish a regulatory base suitable for domestic deep geological disposal status. Based on the collected data, preprocessing and analysis with Python were performed. Keywords and their frequency were extracted from the data through keyword analysis. Through the measured frequency values, the contents of the objects and elements to be regulated in the statutory items were grasped. And through the frequency values of words co-occurring among different sections through the analysis of related words, the association was obtained, and the overall interpretation of the data was performed. The results of analyzing regulations of major foreign countries using text mining are visualized in charts and graphs. Word cloud can intuitively grasp the contents by extracting the main keywords of the contents of the regulations. Through the network connection graph, the relationship between related words can be visually structured to interpret data and identify the causal relationship between words. Based on the result data, it is possible to compare and analyze the factors to be supplemented by analyzing domestic nuclear safety case and regulations.
        6.
        2023.11 구독 인증기관·개인회원 무료
        The Republic of Korea (ROK), as a member state of the IAEA, is operating the State’s System of Accounting for and Control (SSAC) and conducting independent national inspections. Furthermore, an evaluation methodology for the material unaccounted for (MUF) is being developed in ROK to enhance capabilities of national inspection. Generally, physical and chemical changes of nuclear material are unavoidable due to the operating system and structure of facilities, an accumulation of material unaccounted for (MUF) has been issued. IAEA developed statistical MUF evaluation method that can be applied to all facilities around the world and it mainly focuses on the diversion detection of nuclear materials in facilities. However, in terms of the national safeguard inspection, an evaluation of accountancy in facilities is additionally needed. Therefore, in this research, a new approach to MUF evaluation is suggested, based on the Guide to the Expression of Uncertainty in Measurement (GUM) that an evaluation of measurement uncertainty factors is straightforward. A hypothetical list of inventory items (LII) which has 6,118 items at the beginning and end of the material balance period, along with 360 inflow and outflow nuclear material items at a virtual fuel fabrication plant was employed for both the conventional IAEA MUF evaluation method and the proposed GUM-based method. To calculate the measurement uncertainty, it was assumed that an electronic balance, gravimetry, and a thermal ionization mass spectrometer were used for a measurement of the mass, concentration, and enrichment of 235U, respectively. Additionally, it was considered that independent and correlated uncertainty factors were defined as random factors and systematic factors for the ease of uncertainty propagation by the GUM. The total MUF uncertainties of IAEA (σMUF) and GUM (uMUF) method were 37.951 and 36.692 kg, respectively, under the aforementioned assumptions. The difference is low, it was demonstrated that the GUM method is applicable to the MUF evaluation. The IAEA method demonstrated its applicability to all nuclear facilities, but its calculated errors exhibited low traceability due to its simplification. In contrast, the calculated uncertainty based on the GUM method exhibited high reliability and traceability, as it allows for individual management of measurement uncertainty based on the facility’s accounting information. Consequently, the application of the GUM approach could offer more benefits than the conventional IAEA method in cases of national safeguard inspections where factor analysis is required for MUF assessment.
        7.
        2023.10 구독 인증기관·개인회원 무료
        아메리카동애등에 성충은 음식물 폐자원 등 유기물이 있는 곳에 알을 낳는 습성이 있다. 대부분의 농가는 음식 물폐자원을 가공한 단미사료(습식사료)를 유인배지로 활용하여 그 위에 플로랄폼(오아시스)를 놓고 알을 받는 다. 그러나 플로랄폼은 재사용이 불가하고 생분해되지 않는 환경폐기물로서 처리가 곤란하며 포름알데하이드, 카본 블랙 등의 발암물질을 함유한 것으로도 알려져 있다. 이에 본 연구는 먹이원 자체를 활용하여 폐기물이 발생하지 않는 친환경 산란받이를 개발하였으며 일회용으로 사용되는 플로랄폼을 대체하였다. 먹이원으로 활 용할 수 있는 습식사료와 건식사료를 주재료로 하여 제작하며, 습식사료(수분60~80%)와 건식사료(1~10%)를 1:0.5~1 비율로 혼합한 사료 혼합물과 보조첨가제와 물을 포함하여 제작한다. 친환경 산란받이는 기존 플로랄폼 대비 산란율이 34% 증가하였으며 구매비용 또한 75% 절감하였다.
        8.
        2023.10 구독 인증기관·개인회원 무료
        아메리카동애등에 유충은 유기성폐기물을 먹이원으로 하며 그 분해산물인 동애등에분은 비료원료로 활용 가능하다. 그러나 농가에서 나오는 분변토는 염분함량이 높아 단독으로 사용하면 토양에 염류집적의 우려가 있다. 이에 산업곤충인 동애등에 분변토의 염분을 낮춰 퇴비로 활용하고자 옥수수(미백2호)에 5처리(무처리, 동애등에분, 동애등에분:흰점박이꽃무지분(2:8), 동애등에분:퇴비(2:8), 퇴비)로 비료를시용하였다. 옥수수 생 육은 초장, 간장, 웅수장, 착수고를 조사하였고 종실은 이삭중, 이삭장, 착립이삭장, 이삭폭 등을 조사하였다. 처리구별 옥수수 수량(kg/10a)은 무처리구 702.8kg, 동애등에분처리구 835.6kg. 동애등에분:흰점박이꽃무지분 (2:8) 처리구 723.7kg, 동애등에분:퇴비(2:8) 처리구 862.3kg, 퇴비 처리구 803.7kg으로 조사되었다. 동애등에 분변 토를 시판퇴비와 혼합하여 퇴비로 활용하면 옥수수 생산을 증진시키는데 효과적이나 장기적인 실험을 통해 토양과 작물에 미치는 영향을 모니터링해야 될 것으로 판단된다.
        9.
        2023.10 구독 인증기관·개인회원 무료
        Although ethylformate and phosphine fumigants are widely used for pest quarantine, studies related to their mechanism of action and metabolic physiological changes in Drosophila models are still unclear. In this study, we investigated how key metabolites altered by fumigants and cold treatment are associated with and affect insect physiology by comparative metabolome analysis. Fumigant treatment significantly altered cytochrome P450 and glutathione metabolites involved in the detoxification mechanism and showed lower expression of PGF2α involved in the immune response compared to the control. Additionally, most of the metabolites functioned in metabolic pathways related to the biosynthesis of amino acids, nucleotides and cofactors.
        10.
        2023.10 구독 인증기관·개인회원 무료
        아메리카동애등에(H. illucens)는 음식물 폐기물 등 유기성 폐자원을 효율적으로 처리할 수 있는 능력을 가지 고 있어 전세계적으로 주목받고 있는 환경정화 곤충이다. 하지만 유기성 폐자원을 처리 시 가장 큰 문제는 아메리 카동애등에가 먹이인 유기성 폐자원을 소화시킬 때 발생되는 악취이다. 국내에서 현재 아메리카동애등에를 사육하고 있는 농가는 223호로 조사되고 있지만 이중 악취발생 저감장치 등을 설치한 농가는 10%가 안되는 것으 로 생각된다. 따라서 국내에서 동애등에 먹이로 가장 많이 사용되는 습식사료를 먹이로 사용하였을 때 농가 사육 장 안에서 발생되는 복합악취와 지정악취 22종에 대하여 분석하였다. 그 결과, 복합악취는 249배였으며, 지정악 취는 22종 중 7종(암모니아, 메틸메르캅탄, 트라이메틸아민, 아세트알데하이드, 프로피온알데하이드, 뷰틸알 데하이드, i-발레르알데하이드)가 검출되었다. 이중 가장 높은 농도를 나타낸 악취물질은 암모니아로 98.4ppm 이 분석되었다. 또한, 아메리카동애등에를 사육 시 가장 많이 발생되는 암모니아의 발생시기는 사육초기인 1~4 령보다 5령 이후 전생육기 중의 대부분을 발생시키는 것으로 조사되었다. 이러한 결과는 암모니아 저감을 위한 적정시기를 설정하는데 도움이 될 것으로 생각된다.
        11.
        2023.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        APro, developed in KAERI for the process-based total system performance assessment (TSPA) of deep geological disposal systems, performs finite element method (FEM)-based multiphysics analysis. In the FEM-based analysis, the mesh element quality influences the numerical solution accuracy, memory requirement, and computation time. Therefore, an appropriate mesh structure should be constructed before the mesh stability analysis to achieve an accurate and efficient process-based TSPA. A generic reference case of DECOVALEX-2023 Task F, which has been proposed for simulating stationary groundwater flow and time-dependent conservative transport of two tracers, was used in this study for mesh stability analysis. The relative differences in tracer concentration varying mesh structures were determined by comparing with the results for the finest mesh structure. For calculation efficiency, the memory requirements and computation time were compared. Based on the mesh stability analysis, an approach based on adaptive mesh refinement was developed to resolve the error in the early stage of the simulation time-period. It was observed that the relative difference in the tracer concentration significantly decreased with high calculation efficiency.
        4,300원
        12.
        2023.05 구독 인증기관·개인회원 무료
        Since high-level radioactive wastes contain long-lived nuclides and emit high energy, they should be disposed of permanently through a deep geological disposal system. In Korea, the first (2016.07) and the second (2021.12) basic plans for the management of high-level disposal systems were proposed to select sites for deep geological disposal facilities and to implement business strategies. Leading countries such as Finland, Sweden and France have developed and applied safety cases to verify the safety of deep geological disposal systems. By examining the regulatory status of foreign leading countries, we analyze the safety cases ranging from the site selection stage of the deep geological disposal system to the securing of the permanent disposal system to the investigation, analysis, evaluation, design, construction, operation, and closure. Based on this analysis, we will develop safety case elements for long-term safety of deep geological disposal systems suitable for domestic situation. To systemically analyze data based on safety cases, we have established a database of deep geological disposal system regulations in leading foreign countries. Artificial intelligence text mining and data visualization techniques are used to provide database in dashboard form rather than simple lists of data items, which is a limitation of existing methods. This allows regulatory developers to understand information more quickly and intuitively and provide a convenient interface so that anyone can easily access the analyzed data and create meaningful information. Furthermore, based on the accumulated bigdata, the artificial intelligence learns and analyzes the information in the database through deep learning, and aims to derive a more accurate safety case. Based on these technologies, this study analyzed the legal systems, regulatory standards, and cases of major international leading countries and international organizations such as the United States, Sweden, Finland, Canada, Switzerland, and the IAEA to establish a database management system. To establish a safety regulation base suitable for the domestic deep geological disposal environment, the database is provided as data to refer to and apply systematic information management on regulatory standards and regulatory cases of overseas leading countries, and it is expected that it will play a key role as a forum for understanding and discussing the level of safety of deep geological disposal system among stakeholders.
        13.
        2023.05 구독 인증기관·개인회원 무료
        In Korea, borated stainless steel (BSS) is used as a storage rack in spent fuel pools (SFP) to maintain the nuclear criticality of spent fuels. As the number of nuclear power plants and the corresponding amount of spent fuels increased, the density in SFP storage rack also increased. In this regard, maintaining subcriticality of spent nuclear fuels became an issue and BSS was selected as the structural material and neutron absorber for high density storage rack. Since it is difficult to replace the storage rack, corrosion resistance and neutron absorbency are required for long period. BSS is based on stainless steel 304 and is specified in the ASTM A887-89 standard depending on the boron concentration from 304B (0.20-0.29% B) to 304B7 (1.75-2.25% B). Due to the low solubility of boron in austenitic stainless steel, metallic borides such as (Fe, Cr) 2B are formed as a secondary phase. Metallic borides could cause Cr depletion near it, which could decrease the corrosion resistance of the material. In this paper, the long-term corrosion behavior of BSS and its oxide microstructures are investigated through accelerated corrosion experiment in simulated SFP conditions. Because the corrosion rate of austenitic stainless steel is known to be dependent on the Arrhenius equation, a function of temperature, the corrosion experiment is conducted by increasing the experimental temperature. Detail microstructural analysis is conducted using a scanning electron microscope, transmission electron microscope and energy dispersive spectrometer. After oxidation, a hematite structure oxide film is formed, and pitting corrosion occurs on the surface of specimens. Most of the pitting corrosion is found at the substrate surface because the corrosion resistance of the substrate, which has low Cr content, is relatively low. Also, the oxidation reaction of B in the secondary phase has the lowest Gibbs free energy compared to other elements. Furthermore, oxidation of Cr has low Gibbs free energy, which means that oxidation of B and Cr could be faster than other elements. Thus, the long-term corrosion might affect the boron content and the neutron absorption ability of the material. Using boron’s high cross-section for neutrons, the neutron absorption performance of BSS was evaluated through neutron transmission tests. The effect of the corrosion behavior of BSS on its neutron absorption performance was investigated. Samples simulated to undergo up to 60 years of degradation before corrosion through accelerated corrosion testing did not show significant changes in the neutron shielding ability before and after corrosion. This can be explained in relation to the corrosion behavior of BSS. Boron was only leached out from the secondary phase exposed on the surface, and this oxidized secondary phase corresponds to about 0.17% of the volume of the total secondary phase. This can be seen as a very small proportion compared to the total boron content and is not expected to have a significant impact on neutron absorption performance.
        14.
        2023.05 구독 인증기관·개인회원 무료
        CANDU Spent Fuel (CSF) dry storage system, SILO, has been operated from 1992 at Wolsung under 50 year operating license. As of 2023, this system has been operated for over 30 years and its licensed remaining operation time is less than 20 years. When it faces the final stage of operation, it has only two options; moving to a centralized away-from-reactor storage or extending its license atreactor. These two options have an inevitable common duty of confirming the CSF integrity by a “demonstration test”. Since the degradation of CSF and structural materials in the SILO are critically dependent on temperature, two important goals of the ‘DEMO test’ were set as follows. 1. Design of ‘DEMO SILO’: Development of internal monitoring technology by transforming SILO design. 2. Accurate measurement and evaluation of the three-dimensional temperature distribution in the ‘DEMO SILO’ Based on operating real commercial SILO dimension, a conceptual “DEMO SILO” design has been developed from 2022. Because, unlike with commercial Silo, ‘Demo Silo’ must be disassembled and assembled, and have penetration holes. Safety evaluation technologies like structural, thermal and radiation protection analysis also have been developed with design work. ‘Demo SILO’ should evaluate an accurate 3D temperature distribution with minimal number of thermocouples and penetration holes to avoid disruption of internal flow and temperature distribution. For this reason, a ‘Best Estimate Thermal-Hydraulics evaluation system for SILO’ is under development and it will be essential for ensuring temperature prediction accuracy. Construction of a full-scale test apparatus to validate this technology will begin in 2024. In order to supply power to many heaters and monitor temperature gradient inside of this apparatus, it has modular design concept by dividing its whole body to axial 9 sub-bodies which looks like a donut containing a basket at center position.
        15.
        2023.05 구독 인증기관·개인회원 무료
        The Korea Laboratory Accreditation Scheme (KOLAS) is the national accreditation body responsible for providing accreditation services to testing and calibration laboratories. The primary objective of KOLAS is to promote the quality and reliability of laboratory testing by providing nationally and internationally recognized accreditation services. Laboratories accredited by KOLAS are required to meet rigorous international standards set by the International Organization for Standardization (ISO) and are subject to regular assessments to ensure ongoing compliance with the standards. KOLAS accreditation is highly regarded both domestically and internationally, and is recognized for providing high-quality and reliable testing services. The nuclear analysis laboratory at KINAC has been working to establish a quality management system to ensure the external reliability of analytical results and to secure its position as an authorized testing agency. To achieve this, a detailed manual and procedure for nuclear material analysis were developed to conform to the international standards of ISO/IEC 17025. This study presents the preparation process for establishing the management system, focusing on meeting technical and quality requirements for the implementation of the ISO/IEC 17025 standard in the KINAC nuclear analysis laboratory, specifically in the field of chemical testing (dosimetry, radioactive, and neutron measurement subcategories). The preparation process involved two tracks. The first track focused on satisfying technical requirements, with Thermal Ionization Mass Spectrometer (TIMS) and Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) selected as the major equipment for analysis. Analytical methods for determining isotope ratios and concentrations of nuclear materials were determined, and technical qualification was ensured through participation in proficiency test programs, inter-experimenter comparison tests, and uncertainty reports. The second track focused on developing the quality system, including quality manuals, procedures, and guidelines based on the requirements of the ISO/IEC 17025 standard. Various implementation documents were produced during the six-month pilot period, in accordance with the three levels of documents required by the standard. Implementation of ISO/IEC 17025 is expected to have a systematic quality management process for the analysis lab’s operations and to increase confidence in KINAC’s nuclear analysis.
        16.
        2023.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        한반도에 분포하는 백악기 육성퇴적층 중 경상누층군 퇴적물의 기원지 조성과 조구조 환경에 대한 연구는 활발 하게 이루어진 반면에 그 외 퇴적층에 대한 사암의 암석학적 연구는 아직 부족하다. 본 연구에서는 부산 기장군 일광 읍 신평리 해안가 일대에 분포하는 백악기 이천리층의 사암을 대상으로 암석기재학적 연구를 수행하여 기원지의 특성 에 대한 예비 해석 결과를 보고하였다. 이천리층 사암은 미성숙한 조성과 조직을 나타내며 백악기 당시 유라시아 동쪽 연변부에서 일어난 고태평양판의 섭입에 의해 융기하여 발달한 화산호로부터 단시간에 퇴적물이 생성되어 운반된 것으 로 보인다. 그리고 사암 내 부수광물로 크롬 첨정석이 다수 관찰되는데, 이는 기원지에 초고철질암이 분포하였음을 의 미한다. 향후 추가 연구를 바탕으로 크롬 첨정석 기원암의 형성 환경 뿐만 아니라 이천리층 퇴적 당시 경상분지 동남 부의 조구조 환경에 대한 해석과 경상누층군과의 층서 대비가 가능할 것으로 기대된다.
        4,000원
        18.
        2023.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Various linear system solvers with multi-physics analysis schemes are compared focusing on the near-field region considering thermal-hydraulic-chemical (THC) coupled multi-physics phenomena. APro, developed at KAERI for total system performance assessment (TSPA), performs a finite element analysis with COMSOL, for which the various combinations of linear system solvers and multi-physics analysis schemes should to be compared. The KBS-3 type disposal system proposed by Sweden is set as the target system and the near-field region, which accounts for most of the computational burden is considered. For comparison of numerical analysis methods, the computing time and memory requirement are the main concerns and thus the simulation time is set up to one year. With a single deposition hole problem, PARDISO and GMRESSSOR are selected as representative direct and iterative solvers respectively. The performance of representative linear system solvers is then examined through a problem with an increasing number of deposition holes and the GMRES-SSOR solver with a segregated scheme shows the best performance with respect to the computing time and memory requirement. The results of the comparative analysis are expected to provide a good guideline to choose better numerical analysis methods for TSPA.
        4,000원
        19.
        2023.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Sustainable and healthy diet is a challenge in recent world. Despite the global depletion of water resources, Korea has no system for controlling its water footprint. This study established the water footprint tables of Korean food using the Water Footprint Network databases, and applied them into two meal plans for 19~64 year-old adults recommended in the Dietary Reference Intakes for Koreans 2020. Nut, oil, and meat’s water footprints were higher and those of fruit and vegetable were lower. Sesame oil had the highest water footprint of 21,793 L/kg and pineapple had the lowest domestic water footprint of 102 L/kg. Water footprint of one serving size of beef was 925 L, that of chicken was 260 L, and those of soybean were 43 L in global and 81 L in domestic. The water footprint of the recommended 2,400 kcal meal plan was 2,882 L, and that of 1,900 kcal meal plan was 1,915 L. The water resources can be saved by choosing food with lower water footprint. The results of this study can be used in the further researches for more sustainable and healthier Korean diet.
        5,100원
        20.
        2023.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, scones were prepared using Cordyceps powder, described as ‘immortal life’. Cordyceps powder was prepared in 0%, 2%, 4%, 6%, and 8% ratios, and salinity, color, texture, and antioxidant properties were analyzed. The salinity of Cordyceps scones did not show a difference according to the amount of Cordyceps powder added (p=0.364), and the a-, b-values increased significantly (p<0.001). In the case of texture, there was no significant difference in the amount of Cordyceps added. Flavonoids increased significantly as the amount of Cordyceps powder increased (p<0.001). ABTS-radical scavenging capacity increased significantly as the amount of Cordyceps powder increased (p<0.001). Through this study, the antioxidant properties of Cordyceps scones were confirmed.
        4,000원
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