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        검색결과 22

        1.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The government is implementing a policy to expand eco-friendly energy as a power source. However, the output of new and renewable energy is not constant. It is difficult to stably adjust the power supply to the power demand in the power system. Therefore, the government predicts day-ahead the amount of renewable energy generation to cope with the output volatility caused by the expansion of renewable energy. It is a system that pays a settlement amount if it transitions within a certain error rate the next day. In this paper, Machine Learning was used to study the prediction of power generation within the error rate.
        4,000원
        2.
        2023.11 구독 인증기관·개인회원 무료
        The hydride reorientation (HR) of used nuclear fuel cladding after operation affects the integrity during intermediate and disposal storage, as well as the handling processes associated with transportation and storage. In particular, during dry storage, which is an intermediate storage method, the radial hydrogen redistributes into circumferential hydrogen, increasing the embrittlement of used nuclear fuel cladding. This hydride reorientation is influenced by various key factors such as circumferential stress (hoop stress) due to internal rod pressure, maximum temperature reached, cooling rate during storage, and the concentration of precipitated hydrogen during irradiation. To simulate long-term dry storage of used nuclear fuel, hydrogenated Zircaloy-4 cladding (CWSRA) specimens were used in hydride reorientation tests under various hoop stress conditions (70, 80, 90, and 110 MPa) for extended cooling periods (3 months, 6 months, and 12 months). After the hydride reorientation tests, the cladding’s offset strain (%) was evaluated through a ring compression test, a mechanical property test encompassing both ductility and brittleness. In this study, the offset deformation of the hydride reorientation specimens was compared and evaluated through ring tensile tests. In this study, the offset deformation values were compared and evaluated through ring tensile tests of the hydride reorientation test specimens. Hydrogen in zirconium cladding reduces ductility from a physical perspective and induces rapid plastic deformation. Generally, even in hydrogenated unirradiated cladding, it maintains a tensile strength of around 800 MPa at room temperature. However, high hydrogen content accelerates plastic deformation. In contrast, samples with radial hydrogen distribution exhibit fracture behavior in the elastic region below 500 MPa. This is attributed to the directional of radial hydrogen distribution. Specimens with a hydrogen concentration of 200 ppm fracture faster than those with hydrogen concentrations exceeding 400 ppm. This is believed to be due to the ease of reorientation of radial hydrogen in cladding with relatively low hydrogen content. Although the consistency of the test results is not ideal, ongoing research is needed to identify trends in hydride reorientation from a cladding perspective.
        3.
        2023.05 구독 인증기관·개인회원 무료
        In the process of spent fuel dry storage, which is an intermediate management method, it was found that hydrides in the circumferential direction rearranged into radial hydrides. Various factors, such as hoop stress, peak temperature, cooling rate during the storage period, and hydrogen concentration accumulated during the burnup process, significantly affect the susceptibility of spent fuel cladding. In recent studies based on the hydrogen solubility value of about 210 ppm corresponding to the peak temperature of 400°C, if the threshold stress decreases as the hydrogen concentration increases in the low hydrogen range under 210 ppm, the threshold stress increases as the hydrogen concentration increases in the low hydrogen range under 210 ppm. The fundamental cause of this trend is the diffusion of hydrogen into the high-stress region due to the stress gradient formed in the specimen, and hydrogen compounds which remain undissolved in the circumferential direction, even at the peak temperature, play a crucial role to determine the magnitude of the threshold stress. This study evaluated the behavior of hydride reorientation under various hoop stress conditions (70, 80, 90, and 110 MPa) using unirradiated Zircaloy-4(CWSRA) cladding tubes under long-term cooling conditions (3, 6, and 12 months). The results of analyzing the offset strain by hydrogen concentration for long-term cooling showed that specimens with low hydrogen concentration exhibited higher integrity than specimens with high hydrogen concentration at hoop stresses of 90 and 110 MPa. The HR test using irradiated fuel cladding showed that specimens with low hydrogen concentrations exhibited relatively higher susceptibility. To quantify these results, it is necessary to research further in detail by repeated tests.
        4.
        2023.05 구독 인증기관·개인회원 무료
        The hydride reorientation (HR) of the post-irradiated nuclear fuel cladding after use affects the integrity of the spent nuclear fuel. During the dry storage process, which is an intermediate storage method, it was found that the hydride in the circumferential direction is rearranged into radial hydride, and this is believed to be due to factors such as hoop stress, peak temperature, accumulated hydrogen concentration, and cooling rate during the storage period. f(HR) = f(Tmax) + f(σH) + f(CH) + f(△T) + f(10Cy) + f(cooling rate) + ...... To simulate long-term dry storage of spent nuclear fuel, the hydride reorientation behavior was evaluated using unirradiated Zircaloy-4 (CWSRA) cladding with hydrogen charged under various hoop stresses (70, 80, 90, and 110 MPa) at long-term cooling periods (3, 6, and 12 months). Test results showed that as the cooling time increased, the sample with 90 MPa hoop stress at a maximum temperature of 400°C approached the ductility recommendation limit of 2%. In a 90 MPa hoop stress specimen with 3 months cooling period at peak temperature of 400°C, the offset strain was 4.24% at room temperature RCT, while it showed the result of 2.86% for the cooling period of 12 months. On the other hand, the specimen with hoop stress of 110 MPa and cooling period of 12 months showed result of 1.4%. The test results need to take into account errors in hydrogen charging and hydrogen analysis, and it is necessary to consider reproducibility through repeated tests. These results indicate the need for continued attention to the evaluation of the effects of hydride reorientation due to long-term cooling in the context of the integrity of spent fuel.
        5.
        2021.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Diaporthe속은 전세계적으로 중요한 곰팡이 병원균 중 하나이다. 블루베리에 발생하는 병에 관한연구 결과 강원도 춘천시와 고성시의 블루베리 농가에서 5균주의 Diaporthe속을 분리하였다. 이들의 형태적 특징과 분자생물학적 특징을 조사한결과 Diaporthe amygdali, D. eres, D. nobilis, D. phaseolorum, Diaporthe sp.로 동정되었다. 병원성 검정결과 Diaporthe amygdali, D. nobilis, D. phaseolorum 은 상처를 낸 잎에서 5~10mm의 병반을 형성하였다. Diaporthe eres는 상처낸 잎에서 10mm 이상의 병반을 형성하였고 Diaporthe sp.는 상처를 낸 잎에서 5mm 이하의 병반을 형성하였다. 하지만 상처를 내지 않은 잎과 과실에서는 병반을 확인할 수 없었다. 온도 생장특성은 D. eres, D. nobilis, D. phaseolorum, Diaporthe sp.는 25℃에서 D. amygdali는 30℃에서 가장 높은 생장을 보였다. 모든 분리균들은 oxine-copper, benomyl, fluzinam, prochloraz manganese complex에서 80%이상 의 생장저해율을 보였고 captan과 mancozeb는 250ppm, 500ppm에서 dithianon는 500ppm에서 80%이상의 생장저해율을 보였다.
        4,000원
        6.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Molding is the root industry of the manufacturing as a means to mass-produce developed prototypes. Molds are typically divided into injection molds and press mold industries. Injection molds produce the products by injection of molten plastic into a mold, and press molds are molded and bended plate. The ejection system, such as eject pins, is used to separate the manufactured products from the mold, which involves a number of hole operations. Location, diameter and depth of holes are often tabulated and managed collectively when designing 2D drawings. The design efficiency was realized by applying CATIA Automation to the 3D model and bringing in the data of the holes in the Excel data.
        4,000원
        7.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Combining digital automation solutions throughout recent manufacturing process is essential. Advanced robot and mechanical techniques are required for design, manufacture, and distribution process. Manual design of repetitive similar mechanical components during the development phase of these advanced machines and robots can occur wasting time and money. Developed gear design module, which is the power transfer system mechanical component, was programmed in the Visual Basic language in CATIA V5 environment. Automation Process is Based on Parametric Modeling Method. and it was found to be effective in reducing design time compared to designers manual modeling.
        4,000원
        8.
        2018.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The various hydraulic equipments including main control valves are composed of relatively long replacement parts, so the stability is very important. These systems ensure system safety by not delivering pressure to actuators when pressure exceeds the limiting pressure. According to various hydraulic equipments, the required pressure of every hydraulic actuators are differenced. So the optimal design of the main valve is indeed needed. In the previous study, the detail shapes and the boundary conditions of the main control valve were studied by CFD analysis using FLUENT. Based on the previous study, the optimal design of the main control valve is done by applying the parametric modeling technique and then the optimum design of the main control valve is investigated by CFD analysis.
        4,000원
        10.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To control the flow of fluid, several kinds of valves are used. Especially, Main Control Valve (MCV) is the key element of hydraulic system which performs complex control not only controlling the flow of fluid, but also prevent damage of equipment by supplying proper hydraulic pressure to actuator and draining over-supplied hydraulic pressure. While general control valves are producing in domestically, entire quantity of main control valves are depended on importation and it depreciates competitiveness in cost, and time. In this study, to derive the best design of notch structure by following the orifice flow of 6-linked main control valve and the relation between “notch structure” which is the most fundamental element to control the velocity of the fluid and “pressure distribution”, the flow characteristic is compared by comprehending hydraulic pressure and velocity of the fluid using CFD simulation when spool valve is used for “meter-in” and “meter-out” through the opening of the notch structure.
        4,000원
        11.
        2016.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Various types of hydraulic valves are used to control hydraulic equipment including construction equipment such as excavator, crane. etc. The main control valve is a core component, to complex control fluid flow or supplying constant fluid pressure to actuator in accordance operating environment. Excessive flow rate is drained for safety of hydraulic system by main control valve. In this study, the scheme program to change the boundary condition according to behavior of the spool valve is developed. Using this results, the CFD analysis are accomplished.
        4,000원
        12.
        2012.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        ‘조성’은 국내에서 답리작 재배가 가능한 조숙성 트리티케일 품종 개발을 목표로 2010년에농촌진흥청 국립식량과학원에서 육성되었다. 계통은 1992년에 국제밀 옥수수연구소(CIMMYT)에서 FAHAD_5와 RHINO1R.1D 5+10 5D'5B'의잡종에 FAHAD_5를 여교잡하여 작성되었으며,선발된 고세대 계통인 ‘CTSS92Y-A-4Y-0M-5Y0B’에 대해 2006년부터 2007년까지 2년간 생산력 검정시험을 실시하였다. 이 계통은 숙기가빠르고 건물수량이 많아 ‘익산26호’로 계통명을 부여하고 2008년부터 2010년까지 3년간에걸쳐 제주 익산 청원 예산 나주 대구 및진주 등 7개 지역에서 지역적응시험을 실시하여 2010년 11월 신품종으로 선정되었으며, 그특성은 다음과 같다. 트리티케일 신품종 ‘조성’은 농록색 잎, 황색 줄기, 황갈색의 큰 종실을가졌다. 출수기가 전국 평균 4월 24일로 표준품종인 ‘신영’보다 5일, 제주지역에서는 10일빨랐다. ‘조성’의 한해는 ‘신영’과 대등하였고,도복에 강하였으며, 습해 흰가루병 및 잎녹병등에 저항성이었다. 건물수량은 ha당 평균 14.5톤으로 16.5톤인 ‘신영’에 비해 12% 낮았다.‘조성’은 ‘신영’에 비해 조단백질 함량이 5.3%로 다소 낮았으나 NDF 및 ADF 함량(%)이 낮아 TDN 함량(%)이 64.0%로 ‘신영’에 비해2.1% 높았다. ‘조성’은 ‘신영’에 비해 천립중이46.6g, 중이 692g으로 무겁고, 종실수량이 ha당 5.1톤으로 ‘신영’보다 40% 많았다. 적응지역은 1월 최저평균기온이 10 이상인 지역이면 전국 어느 곳에서나 재배가 가능하며, 특히벼 이앙이 빨라 월동작물의 재배가 곤란한 지역에서도 답리작 재배를 통한 조사료 생산이가능하다.
        4,000원
        13.
        2007.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
          This study is evaluation of shift-workers’ sleep and social life related to hospital workers’ performance and health. We researched shiftworkers’ sleep, sleeping quality and social relations using a questionnaire method to shiftworkplace scattered Daeje
        4,000원
        14.
        2006.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
          This study is provide information in the development of energy conservation technologies by means of technological demand survey covering energy market and industrial field among energy-related technologies.   For this purpose, we check both the present
        4,000원
        15.
        2005.05 구독 인증기관 무료, 개인회원 유료
        This study is to provide information in the development of energy conservation technologies by means of technological demand survey covering energy market and industrial field among energy-related technologies. For this purpose, we check both the present state of energy technologies and trends of social change in Korea, and then combine social needs with major, bottleneck, and essential technologies required for the future. The range of this study covers the field of industry, kiln, furnace, metal, building, transport, and electricity. For case study, valid 120 companies among the 500 companies selected randomly in the energy data-base of Korea institute of energy research (KIER) are considered.
        3,000원
        16.
        2015.09 KCI 등재 서비스 종료(열람 제한)
        농촌진흥청 국립식량과학원에서는 용도별 품종의 다양화를 위해 답리작 적응 과자용 밀 품종 ‘고소’를 개발하였다. 고소밀은 1998년도에 연질인 고분밀을 모본으로 하고, 숙기가 빠른 올밀을 부본으로 인공교배하여 SW98148 조합을 육성하였다. 경기도 연천에서 집단재배 후 계통을 전개하여 초형과 수형이 양호하며 내한성이 강한 계통인 SW98148-YB-9-2-4-1-3-1을 2006년부터 2개년간 생산력 검정을 거쳐 ‘익산 320호’로 계통명을 부여하였다. 그 후 2008년부터 3개년 동안 지역적응시험을 실시한 결과 숙기가 빠르며 수량성이 높고, 과자적성이 우수하여 2010년 농작물 직무육성 신품종심의회에서 ‘고소’로 명명하였다. 고소밀의 파성은 Ⅱ형으로 춘파형이고, 엽색은 녹색이며 이삭은 방추형이고, 종자는 중간 크기로 적색이다. 출수기와 성숙기는 밭상태 조건에서 각각 4월 28일과 6월 7일, 논상태에서는 각각 4월 25일과 6월 4일로 비슷하다. 고소밀의 리터중(799 g/L)과 천립중(42.5 g) 은 금강밀(804 g/L과 46.7 g)보다 낮고, 내한성(4.4%)과 수발아(4.0%) 저항성이 강하고, 내도복성이 높다. 고소밀의 제분율(63.77%), 단백질(9.8%), 침전가(30.0 ml)과 글루텐(7.2%) 함량은 금강밀(73.6%, 12.6%, 50.0 ml과 10.8%)보다 낮고, 과자적성이 우수하였다. ‘고소밀’의 HMW-GS 조성은 Glu-A1에서 2*, Glu-B1에서 7+8을 나타내 금강밀과 조성이 같았으나, Glu-D1에서 2.2+12가 발현되었다. GBSS 조성은 금강밀과 같은 야생형이고, Pinb-D1은 야생형으로 금강밀과 다른 특성을 나타냈다. 지역적응시험에서 밭상태 수량은 657 kg/10a, 논상태 수량은 561 kg/10a로 금강밀보다 21%와 7% 증수하였다.
        17.
        2014.09 KCI 등재 서비스 종료(열람 제한)
        ‘수양’은 우리나라에서 재배가 가능한 조숙 양질 다수성 쌀귀리 품종을 육성하고자 1996년에 조숙성인 ‘식용귀리’를 모본으로, 조숙 대립 겉귀리 계통인 ‘귀리23호’를 부본으로 인공교배를 하여 계통 및 집단육종법에 의해 선발된 ‘SO96025-B-303-44-2-4’ 계통이다. 이 계통은 2003년부터 생산력검정시험을 거쳐 계통명이 ‘귀리56호’로 명명되었고, 2005년부터 지역적응시험을 거쳐 2010년에 육성된 품종이다. ‘수양’의 잎은 담녹색이고 폭과 길이는 좁고 짧으며, 종실은 길고 황갈색이다. ‘수양’의 출수기는 재배지 평균 4월 28일로서, 기존에 육성된 ‘선양’에 비해 11일 빨랐으며, 성숙기 또한 6월 7일로서 ‘선양’에 비해 6일 빨랐다. ‘수양’의 내한성은 표준품종인 ‘선양’ 보다 강하였고, 도복도 ‘선양’과 같은 수준이었다. ‘수양’은 m2당수수가 568개로 51개 적었으나, 1수립수는 73개로서 7개 많았고, ℓ중은 646 g으로서 596 g인 ‘선양’에 비해 50 g, 천립중은 29.2 g으로 4.2 g 무거운 편이었다. 지역적응시험에서 ‘수양’의 평균 종실 수량은 4.35 톤/ha으로 표준품종인 ‘선양’보다 29% 많았다. ‘수양’은 ‘선양’에 비해 탈부율이 100%로 높고, 조단백질 함량이 11.3%, 베타글루칸 함량이 4.7%로 표준품종인 ‘선양’과 비슷하였다.
        18.
        2014.06 KCI 등재 서비스 종료(열람 제한)
        Electrochemical reductive extraction of tin from semiconductor plating process wastewater was experimented using synthetic wastewater. Copper and graphite plate were used as a cathode and an anode, respectively. The tin extraction could be optimized in pH 0.5 and polar space of 60 mm. The extraction rate of tin per minute was increased as current and initial tin concentration increased, and more than 87% and 97% of tin could be extracted within 80 minutes at 500 mg/L and 1,000 mg/L of initial tin concentration, respectively. The electrochemical reaction orders and kinetic coefficients were 1.24 ~ 1.26 and 0.004 ~ 0.006 (L/mg)(n − 1)min−1. The residual concentration of tin could be expressed as Ct= (Co −0.246+ 0.0012t)−4.065.
        19.
        2013.07 서비스 종료(열람 제한)
        ‘Jungmo2503’ (Hordeum vulgare L.), a new ruminant-palatability forage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA in 2011. It was derived from the cross between ‘Dongsanpi81’ and ‘Kangbori’. Among the cross made in 1999, a promising line, SB992028-B-B-B-B-B-2, showed good characteristics in potential forage yield in the yield Trial tested at Iksan in 2007 to 2008 designated as Iksan 449. The line in the Regional Yield Trials (RYT) tested in eight locations around Korea for three years from 2009 to 2011, and was released as the name of ‘Jungmo2503’. It has the growth habit of group Ⅰ, erect plant type, green leaf and hood spike. Its average heading and maturing dates were on May 2, and May 29, respectively, with are similar to check cultivar ‘Yuyeon’. The cultivar had 102cm of culm length, 691 spikes per m2 and it showed better rate of leaf, winter hardiness, and resistance to BaYMV than those of the check cultivar. The average forage yield of ‘Jungmo2503’ was about 10.9 ton ha-1 in dry matter in paddy field. ‘Jungmo2503’ also showed 9.4% of crude protein content, 27.3% of ADF (Acid Detergent Fiber), 49.0% of NDF (Neutral Detergent Fiber), and 67.3% of TDN (Total Digestible Nutrients), including higher grade of silage quality for whole crop barley.
        20.
        2013.07 서비스 종료(열람 제한)
        ‘Jungmo2502’ (Hordeum vulgare L.), a new ruminant-palatability forage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA in 2011. It was derived from the cross between ‘Samheung/Suwon 300’ and ‘Milyang 100’. Among the cross made in 2000, a promising line, SB00T2018-B-B-B-B-3, showed good characteristics in potential forage yield in the yield Trial tested at Iksan in 2007 to 2008 designated as Iksan 448. The line in the Regional Yield Trials(RYT) tested in eight locations around Korea for three years from 2009 to 2011, and was released as the name of ‘Jungmo2502’. It has the growth habit of group Ⅵ, erect plant type, green leaf and awnless spike. Its average heading and maturing dates were on May 4, and May 30, respectively, with are similar to check cultivar ‘Youngyang’. The cultivar had 98cm of culm length, 607 spikes per m2 and it showed better rate of leaf, winter hardiness, and resistance to BaYMV than those of the check cultivar. The average forage yield of ‘Jungmo2502’ was about 11.0 ton ha-1 in dry matter in paddy field. ‘Jungmo2502’ also showed 8.7% of crude protein content, 21.9% of ADF (Acid Detergent Fiber), 40.7% of NDF (Neutral Detergent Fiber), and 71.6% of TDN (Total Digestible Nutrients), including higher grade of silage quality for whole crop barley.
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