검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 30

        1.
        2023.11 구독 인증기관·개인회원 무료
        To achieve permanent disposal of radioactive waste drums, the radionuclides analysis process is essential. A variety of waste types are generated through the operation of nuclear facilities, with dry active waste (DAW) being the most abundant. To perform radionuclides analysis, sample pretreatment technology is required to transform solid samples into solutions. In this study, we developed a dry ashing-microwave digestion method and secured the reliability of the analysis results through a validity evaluation. Additionally, we conducted a comparative analysis of the radioactivity of 94Nb nuclides with and without the chemical separation process, which reduced the minimum detectable activity (MDA) level by more than 65-fold for a certain sample.
        2.
        2023.11 구독 인증기관·개인회원 무료
        Once decommissioning begins, it is expected that large amount of radioactive wastes will be produced in a short period of time. The expected amount of radioactive wastes from Kori unit 1 NPP are approximately 80,000 drums (base on 200 L). By minimizing the amount of radioactive wastes generated through decontamination and reduction, KHNP has set the final target for the amount of radioactive wastes to be delivered to the disposal site at approximately 14,500 drums. Here, plasma torch melting technology is an essential technology for radioactive wastes treatment during nuclear power plants decommissioning and operation, because of its large volume reduction effects and the diversity of disposable wastes. KEPCO KPS was able to secure experience in operating Plasma Torch Melter (PTM) by conducting a research service for ‘development of plasma torch melting system advancement technology’ at KHNP-CRI. This study will compare kilo and Mega-Watt class PTM, largely categorized into facility configurations, operating parameters, and waste treatment. Based on this study, it would be desirable to operate PTM with approximate capacity according to the frequency and amount of waste production, and suggest volume for a kilo and Mega-watt class plasma torch in the melting furnace respectively. This plays to its strengths for both a kilo and Mega-watt class PTM.
        5.
        2022.10 구독 인증기관·개인회원 무료
        We conducted multi-elements determination of reference material certified by the Inorganic Ventures, IV-26, using iCAP 7400 ICP-OES of Thermo Fisher Scientific. And we statistically evaluated analysis results by introducing the in-house proficiency evaluation method implemented at the Ministry of Food and Drug Safety. Ca, Co, Fe, Mg, Ni, and V were selected as target elements, and extended uncertainty was estimated at a confidence level of about 95% and coverage factor k = 2. Five parameters incurred at manufacturing process (standard solution, calibration curve, repeated measurement and dilution factor of the test sample) were considered when determining the uncertainty. En-score can be calculated using the formula En=(x-X)/(Ulab 2+Uref 2)1/2 described in KS Q ISO 13528, where x, Ulab, X, and Uref are the test results, the uncertainty of the result, and the certified value and the uncertainty of the value. And if the absolute value |En| is less than 1, it can be evaluated as a satisfied value. As a result of ICP-OES analysis, each concentration of the elements to be measured was almost similar to the certified concentration of the reference material, and the uncertainty was slightly different. Also since evaluation on multi-elements determination had an En-score within 1, it was confirmed that the analysis results satisfied En evaluation.
        6.
        2022.10 구독 인증기관·개인회원 무료
        KHNP-CRI has developed Mega-Watt Class PTM (Plasma Torch Melter) for the purpose of reducing the volume of radioactive waste and immobilizing or solidifying radioactive materials. About 1 MW PTM is a treatment technology that operates a plasma torch and puts drum-shaped waste into a melter and radioactive waste in the form of slag is discharged into a waste container. Since only the overflowing slag is discharged from the melter, the discharge is intermittent. Therefore, solidification occurs in the process of discharging the melt. It is difficult to accumulate evenly in the waste container, and there is also an empty space. Solid radioactive waste must be disposed of to meet the acceptance criteria for radioactive waste. Plasma-treated solid waste raised concerns about the requirements. The waste solidification output in a slag container gave us some concerns for the waste package’s solidification and encapsulation requirements. The plasma-treated solid waste process to meet the acceptance criteria will be cost and need time consuming. Thus, a induction heating will be introduced to meet solidification requirements and test criteria of the solidification waste for the waste package disposal.
        7.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated alterations in the health behaviors and eating habits due to the coronavirus disease 2019 (COVID- 19) pandemic. An online survey was administered to 270 university students from September 22, 2021 to October 26, 2021. While the frequency of eating at home had increased during the COVID-19 pandemic compared to before the pandemic, there was a decrease in the frequency of eating out, drinking, and eating vegetables. However, the frequency of eating delivery, takeout, and convenience foods and the utilization of online shopping and delivery apps had considerably increased. In addition, when selecting menus, considerations of health, hygiene, and convenience were more important during the COVID-19 pandemic than before the COVID-19 pandemic. Physical activity more than 3 days a week had decreased, whereas sedentary time showed a proportionate increase. The percentage of people who perceived their health status to be worsening was determined to have increased during the COVID-19 pandemic. To prepare for the era of infectious diseases, future research needs to identify health behaviors and dietary problems by administering surveys that include a large sample size and participants of various ages. Moreover, health promotion and nutrition management plans should be prepared accordingly.
        4,500원
        8.
        2021.11 구독 인증기관 무료, 개인회원 유료
        캐나다의 연주 컨설턴트인 Saul Miller에 의하면 마인드 콘트롤을 잘 하는 연주자들은 긍정적인 효과들을 나타낸다고 한다. 이처럼 연주에서 마인드 콘트롤은 기술만큼 매우 중요한 요소이다. 이 논문은 실용음악의 연주환경에서 마인드 콘트롤의 중요성과 필요성에 대해 기술하였다. 또한 현재 실용음악 교육 분야에서 이 주제에 대해 어떻게 인식하고 대응하고 있는지에 대해 조사하고 실용음악 관련 전공자들에게 실제 연주환경에서 어떠한 마인드 콘트롤을 하고 있고 긍정적 효과는 무엇인지에 대해 연구하였다. 이 연구의 목적은 실용음악 관련 교수자와 학습자 그리고 연주자들에게 마인드 콘트롤의 효과와 중요성에 대한 연구 결과를 제공하여 연주환경에서 좀 더 긍정적인 효과를 도출해 낼 수 있도록 하는 것이다. 연구 방법은 마인드 콘트롤의 긍정적 효과에 대해 분석 하였고 서울지역 실용음악 전공생들 100여명에게 설문 조사를 통해 첫째 이 주제에 대해 중요성을 인지하고 있는지, 둘째 실제 마인드 콘트롤을 하고 있는지, 셋째 어떠한 마인드 콘트롤을 하고 있는지, 마지막 넷째 마인드 콘트롤을 했을 때 나타나는 긍정적 효과는 무엇인지에 대해 연구하였 다. 분석결과 마인드 콘트롤의 효과가 크고 중요한 것으로 나타났지만 교육기관들에서는 마인드 콘트롤에 대해 크게 인식을 하거나 전문적으로 교육하지 않고 있으며 전공생들도 45%만이 중요성 을 인지하고 있었다. 또한 30%의 전공생들이 연주에서 전문적이지 않은 간단한 마인드 콘트롤을 하고 있으며 85%의 학생들이 긍정적인 효과가 있었다는 결과들이 도출되었다.
        4,300원
        9.
        2021.11 구독 인증기관 무료, 개인회원 유료
        이 논문은 미래 교육 시스템에 실용음악 교육 분야가 효과적으로 대응할 수 있도록 돕는 목적을 가지고 있으며 4차산업혁명을 활용한 교육의 필요성에 대해 기술하고 한국의 실용음악관련 대학교와 전공생들이 이 분야에 대해 어떻게 인식하고 사용자 입장에서 어떤 기술을 필요로 하는지에 대해 연구하였다. 연구 방법은 외국의 실용음악관련 학교들과 서울 소재 대학들의 커리큘럼 분석을 통해 4차산업을 중심으로 하는 미래 교육에 대해 인지하고 교육을 하고 있는지에 대해 비교 분석하였고 실용음악 관련 대학의 전공생들에게 설문를 통해 미래교육 시스템과 중요성 대한 인식과 각자의 세부전공분야에 적용할 수 있는 방법에 대해 조사하였다. 연구결과 대부분의 실용음악 대학들은 미래교육과 학제융합에 대응하는 커리큘럼을 가지고 있지 않은 것으로 나타났으며 학생들의 인식 또한 낮은 것으로 분석되었다. 하지만 각종 미디어와 게임 등으로 기성세대보다 먼저 메타버스를 경험한 엠지세대이기 때문에 이 기술들에 대해 인지하거나 이해하는 속도가 빨랐고 세부전공분야에 효과적으로 적용시킬 수 있는 창의적인 방법을 제시할 수 있었다. 실용음악 관련 교육현장과 학생들이 전공분야의 미래 시장에 대해 인지하는 능력을 높이고 대응할 수 있는 능력이 향상 된다면 다가올 4차산업혁명에 효과적으로 대응할 수 있는 인재를 양성할 수 있을 것으로 예측하였다.
        4,600원
        10.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study examined the effect of ultraviolet (UV) application on bacterial disinfection in a commercialized humidifier using ultrasonic wave (UW). To accurately examine disinfection kinetics in tap-water condition, tap-water was sterilized using a filter, and then inoculated with pure cultures of E. coli and P. putida with known viable counts. The disinfection kinetic characteristics were experimentally compared when UV alone, UW alone, and UW+UV together were applied in disinfecting the added bacteria in the commercialized humidifier. When UV alone was applied, bacterial disinfection kinetics followed a first-order decay reaction, and showed an approximately 10-time weaker disinfection compared to the typical UV disinfection in water treatment or wastewater treatment. When UW alone was applied, bacterial disinfection kinetics followed a second-order decay reaction with a low disinfection rate constant of 0.0002 min-1(CFU/mL)-1. When UV and UW were applied together, however and interestingly, the disinfection rate constant (0.0211 min-1(CFU/mL)-1) was approximately 100 times increased than that for the UW alone case. These results revealed that the co-use of UV and UW can provide synergistic effect on bacterial disinfection in a tap-water condition in household humidifiers.
        4,000원
        11.
        2020.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        적외선 유도 무기 체계의 발달로 항공기의 생존성은 지속적으로 위협받고 있으며, 항공기의 생존성을 향상시키기 위한 적외선 스텔스 기술 관련 연구가 진행되고 있다. 본 논문에서는 적외선 유도 미사일이 항공기와 배경 간의 대비 신호를 탐지하는 것에 주목하여 비행 조건에 따른 항공기의 최적 적외선 신호를 분석하고자 하였다. 이를 위해 항공기의 비행 조건을 고려하여 유동 해석과 대류, 전도, 복사 3차원 열전달 해석을 수행하였고, 동체 표면 온도를 도출하여 항공기 주변 유동 특성을 기반으로 항공기의 적외선 신호를 분석하였다. 더 나아가, 비행 조건 별로 최적 적외선 신호를 갖기 위한 최적 방사율을 도출하였고, 비행 조건 별로 최적 방사율을 동체 표면에 적용했을 때 적외선 신호 저감 효과를 분석하였다.
        4,000원
        12.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The effects of supplemental lighting (SL) timing on vegetative growth and the photosynthetic assimilation rate of young Cymbidium hybrids were examined. Nine month old C. ‘Yang Guifei’ and ‘Wine Shower’ were treated with four different SL timings: 22:00 – 02:00 (middle of the night, MN); 17:00 – 21:00 (end of day extension, DE); 07:00 – 09:00 plus 17:00 – 19:00 (both beginning and end of the night as split day extension, SDE), and non SL (8/16 h, short day, SD) for 4 months. All SL were provided by two types of 100% red LEDs (640 and 660 nm), with 150 μmol・m-2 ・s-1 and 800 μmol・mol-1 of CO2 supplied during the night (16 h). Pseudobulb diameters were significantly higher under SL treatments compared with the SD of both cultivars, irrespective of SL timing. Net photosynthetic assimilation rates were enhanced with increased SL, due to the additional photosynthesis and reduction of dark respiration. Thus, daily net photosynthetic amounts of SL treatments effectively increased photosynthesis compared to the SD. These results indicate that SL helps promote vegetative growth by enhancing photosynthesis. Since there were no significant differences among the SL timings when CO2 was provided uniformly during the night, we concluded that growth and photosynthesis of young Cymbidium do not depend on the timing of SL application, but are related to the daily light integrals, which is the amount of photosynthetically active photons delivered over 24 hours.
        4,000원
        17.
        2018.04 구독 인증기관·개인회원 무료
        Aronia is difficult to eat because it has a bitter taste, bitter taste, and sour taste. Because processing is essential for eating, quality information suitable for processing is needed. This experiment was carried out to confirm the step suitable for processing. Four grades of ripening were collected from 3 varieties (Viking, Nero, McKenzie) based on color, and compared with samples stored for 2 weeks after harvesting. Physicochemical properties such as color, hardness, sugar content, pH and acidity, functional components such as total polyphenols and flavonoids, and antioxidative activities such as DPPH and ABTS were investigated. When compared according to varieties, the hardness of the first degree was highest in other degrees, Depending on harvest time, first degree was higher than other degrees and it decreased with harvest time. Varieties was not significant different lightness, redness and yellowness value. compared according to harvest time, redness was the highest in second degree and lightness, yellowness decreased with harvest time. sugar content was highest in Nero and Mckenzie, birx value increased significantly of ripening and increased with harvesting time. pH was found to be highest in Nero, acidity value was the highest in viking. DPPH, ABTS radical scavening were Nero varieties had the highest radial scavening and increased significantly as the ripening degree increased. Total phenol and flavonoid contents were found to be highest in Nero, the highest content was showed at the first degree of harvesting. The most suitable stage for the processing was considered to be the best after post harvest treatments considering brix, hardness and acidity.
        1 2