• 한국재료학회지
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• 제3권5호
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• pp.476-481
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• 1993

A site 복합 페로브스카이트 구조인 $(Na_{1/2}{\;}La_{1/2})TiO_3$ 세라믹스의 고주파 유전특성을 조사하였다. $1000^{\circ}C$에서 4시간 하소하고 $1350^{\circ}{\;}~{\;}1450^{\circ}C$에서 소결했을 때 치밀한 소결체가 되었다. NLT의 겉보기 밀도는 $4.95g/\textrm{cm}^3$, 상대밀도는 96.4%였으며, 격자상수(a)가 $3.873{\AA}$인 단순 입방정 구조였다. NLT의 유전율은 밀도가 높아짐에 따라 증가하였고 품진계수 Q는 평균 결정립 크기가 커짐에 따라 증가하였다. $1400^{\circ}C$에서 4시간 소결한 NLT는 ${\varepsilon}_r=125$, Q=2842(fo=3 GHz), ${\tau}_f=465$의 유전특성을 나타내었다.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2002년도 창립 10주년 기념 국제학술심포지움
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• pp.46-53
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• 2002

The self-sufficiency of rice production was attained in 1975 through development of Tongil-type high-yielding rices and rapid dissemination to farmers and innovation of cultivation technologies, so-called "green revolution" in Korea. It can be continued during the last twenty seven years except some years with meterological disasters. The national average of milled rice yield per ha was only 3.1 ton at the first half of 1960′s, but it drastically increased to 5.0 ton at the 2nd half of 1990′s. Also, the rice quality was highly improved through the continuous varietal improvement of high-yielding japonica rice cultivars. The amounts of rice stock will go beyond about 1.9 million tons in 2002 due to the recent continuos bumper rice crop and relatively rapid reducing in rice consumption. There are so many rice brands over 1,200 in Korea, but most of rice commodities are not enough controlled in terms of marketing quality and palatability of cooked rice. Although the most rice brands are not properly controlled in quality management, its average level of grain quality is largely improved through the continuously increased diffusion of newly-developed high-quality rice cultivars since 1991. The rapid construction of rice processing complex(RPC) since 1992 also accelerates the production and distribution of brand rices. Especially, about half of distribution amounts are covered by brand rice commodities of the agricultural cooperative associations. The rice is mainly consumed by the type of cooked rice. The amounts of rice consumption for food processing is only below 4% of total rice consumption. The processed rice foods is mainly consumed as various processed cooked rices, rice cakes, and rice wines.

• Journal of Biosystems Engineering
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• 제20권1호
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• pp.47-57
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• 1995

Rice Processing Complex(RPC) have being constructed with a rice mill plant and a facility of drying and storage to overcome problems caused by UR and to produce good quality of rice. An optimal design of a rice mill plant was required to successfully construct and operate it. The development of a simulation model was essential to the design of a rice mill plant. So, all the objectives of this study were to develop a simulation model for the design of a rice mill plant and to develop and evaluate the rice mill system. In this study the simulation model was developed to design a rice mill plant using SLAMSYSTEM, one of simulation languages. The results of this study were as followings. 1. A simulation model was developed with SLAMSYSTEM to represent the processes of a rice mill plant. The simulation model was used to design a rice mill pilot plant with the capacity of 0.5 ton per hour. The rice mill pilot plant was analyzed by the model with alternatives. 2. In the simulation the rice mill system was much influenced by the separating efficiency of a brown rice separator. Especially, the bottleneck of grain flow occurred at the buffer tank for brown rica. separator under 50% separating efficiency of brown rice separator. Hence, as the alternative simulation was conducted under 60% , 70% separating efficiency of brown rice separator, the bottleneck of the system could be minimized at the 60% separating efficiency of brown rice separator. 3. In the alternative simulation the bottleneck of the system was minimized under the hulling capacity of 1 t/h and 60% separating efficiency of brown rice separator with the capacity of 1 t/h. Under such a condition the max. weight of waiting entities at buffer tanks was less 250kg. So, the capacities of the buffer tanks were determined in the basis of simulation results. 4. The milled rice recovery and head rice recovery of the milling system were 74% and 92% in the simulation, respectively. These results of simulation almost corresponded to those of actual rice mill plants. The developed simulation model could be well applied to design a rice mill plant.

• 천문학회보
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• 제46권1호
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• pp.57.2-57.2
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• 2021

Variability in Young Stellar Objects (YSOs) can be caused by time-dependent accretion rates, geometric changes in the circumstellar disks, the stochastic hydromagnetic interactions between stellar surfaces and inner disk edges, reconnections within the stellar magnetosphere, and hot/cold spots on stellar surfaces. We uncover ~1400 variables from a sample of ~5300 YSOs in nearby low-mass star-forming regions using mid-IR light curves obtained from the 5.5-years NEOWISE All Sky Survey. The mid-IR variability traces a wide range of dynamical, physical, and geometrical phenomenon. We classify six types of YSO variability based on their light curves: secular variability (Linear, Curved, Periodic) and stochastic variability (Burst, Drop, Irregular). YSOs in earlier evolutionary stages have higher fractions of variables at all types and higher amplitudes for the variability. Along with brightness variability, we also find a diverse range of secular color variations, which can be attributed to a competitive interplay between the variable accretion luminosity of the central source and the variable extinction by material associated with the accretion process. We compare the variability of known FUors/EXors and VeLLOs/LLSs, which represent two extreme ends (burst versus quiescent) of the episodic accretion process; FUors/EXors have a higher fraction of variables (65%) than VeLLOs/LLSs (41%). Short-term (few day) and long-term (decades) variability, as well as possible AGB contamination in the YSO catalogues, are also discussed.molecules become more complex by surface chemistry induced directly by high energy photons or by the thermal energy diffused over heated grain surface. Therefore, the ice composition is an

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.23-23
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• 2022

Recently, soybean production and market price are unstable, even if demand of soybean is maintained. Diverse conditions such as climate change, a decrease in rural population, and consuming affect food industry. In this situation, food security is soaring as important key-word again, and MAFRA is promoting policies for improving soybean self-sufficiency with the goal of 40% until 2030. The point of policy is to extend a production and stabilize a demand for soybean with supporting large-scale soybean paddy-field complex. According to the background, soybean breeding and production research in NICS are proceeded with three parts. First, production improvement with soybean cultivation land enlargement and high-yield cultivar development. Various growth period soybean cultivars for double cropping, irrigation management technologies in paddy field, and hyper-yield and specific-region adaptable cultivar development. Second, reduction of production expense with mechanized cultivation and digital-based field management technologies. Third, consumer-friendly and high quality soybeans with high protein cultivar for alternative protein usage and high food process-ability for soy milk, tofu, soybean sprouts, and grain usage. Each part need to be combined and advanced to improve soybean industry and soybean self-sufficiency.

• Nuclear Engineering and Technology
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• 제56권7호
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• pp.2584-2594
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• 2024

A novel approach to incorporating oxide formers into ferritic ODS production has been developed using the co-precipitation technique. This method enables the tailored design of complex nano-oxides, integrated during Mechanical Alloying (MA) and precipitated during Spark Plasma Sintering (SPS) consolidation. Findings illustrate that co-precipitation effectively produces nano-powders with customised compositions, enriching Y, Ti, and Zr in the ferritic grade to condition subsequent oxide precipitation. While the addition of Y-Ti-Zr-O nano-oxides did not prevent the formation of Y-Al-O and Al-containing nano-oxides, these were refined thanks to the presence of well-dispersed Zr. Additionally, the Spark Plasma Sintering (SPS) parameters were optimised to tailor the bimodal grain size distribution of the ODS steels, aiming for favourable strength-to-ductility ratios. Comprehensive microstructural analyses were performed using SEM, EDS, EBSD, and TEM techniques, alongside mechanical assessments involving microtensile tests conducted at room temperature and small punch tests carried out at room temperature, 300 ℃, and 500 ℃. The outcomes yielded promising findings, showcasing similar or better performance with conventionally manufactured ODS steels. This reinforces the effectiveness and success of this innovative approach.

• 암석학회지
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• 제21권3호
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• pp.287-307
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• 2012

영남육괴 지리산지구의 남동부에 위치하는 연구지역은 선캠브리아기 지리산 변성암복합체와 하동 북부 회장암복합체 그리고 이들을 관입하는 중생대 화성암류 등으로 주로 구성되어 있고, 지체구조는 한반도의 일반적인 방향인 북동-남서 방향이 아닌 남북 방향으로 발달한다. 본 논문은 하동 북부 회장암복합체와 그 주변부의 지리산 변성암복합체에 발달하는 남북 방향의 지체구조 형성과 관련된 지질구조를 규명하기 위하여 이들 구성암류에 대한 변형단계별 구조적 특성을 연구하였다. 그 결과 연구지역의 지질구조는 적어도 세 번의 변형단계를 거쳐 형성되었음을 알게 되었다. (1) $D_1$ 변형은 $S_0$ 엽리의 상부가 남동쪽으로 이동하는 대규모 연성전단작용으로 지리산 변성암복합체와 하동 북부 회장암복합체에 $F_1$ 칼집 내지 "A"형 습곡과 $F_1$ 습곡축면에 (준)평행한 $S_{0-1}$ 복합엽리 내지 $S_1$ 엽리와 $D_1$ 연성전단대 그리고 $F_1$ 습곡축에 평행한 $L_1$ 신장선구조를 형성시켰다. (2) $D_2$ 변형은 동서 방향의 압축 지구조환경 하에서 $D_1$ 구조요소를 (재)습곡시키는 남북 방향의 $F_2$ 개방, 밀착, 등사, 층간 습곡과 $F_2$ 습곡축면에 (준)평행하게 발달하는 $D_2$ 연성전단대와 $S_{0-1-2}$ 복합엽리 내지 $S_2$ 엽리와 $D_2$ 연성전단대에 수반된 S-C-C' 구조와 $L_2$ 신장선구조를 형성시켰다. 지질도 규모의 $F_2$ 습곡의 날개부에 해당하는 하동 북부 회장암복합체와 지리산 변성암복합체의 동쪽 경계부를 따라서는 $F_2$ 수동적 습곡작용 동안에 입도 세립화와 함께 압쇄구조와 신장선구조를 형성시키는 압쇄암화과정에서 적어도 1.4 km 이상의 폭을 갖고 연장성 있는 남북 방향의 $D_2$ 연성전단대(하동전단대)가 형성되었다. (3) $D_3$ 변형은 남북 방향의 압축 지구조환경 하에서 동서 방향의 $F_3$ 킹크 내지 개방 습곡을 형성시켰고, $D_3$ 변형 이전의 남북 방향 구조요소들을 국부적으로 (동)북동 내지 (서)북서 방향으로 재배열시켰다. $D_2$ 변형 이전의 $D_1$ 광역 지체구조의 방향성은 현재와 달리 북동-남서 방향이었다. 하동 북부 회장암복합체와 그 주변부의 지리산 변성암체에 발달하는 광역적인 남북 방향의 지체구조는 북동-남서 방향의 $D_1$ 지체구조가 $F_2$ 능동 및 수동적 습곡작용에 의해 남북 방향으로 재배열되어 형성되었다. 연구지역의 세 번의 변형작용은 (북)북동 방향의 염기성 암맥군의 관입 집중기로 알려진 고생대 말 이전에 발생하였다.

• 한국작물학회지
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• 제59권1호
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• pp.1-15
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• 2014

국산밀을 재배하는 전국 175농가를 대상으로 2년 동안 재배 현황에 대한 자료를 수집 분석한 결과, 평균 재배 경력과 재배면적은 7.7년과 2.4~3.3 ha였으며, 재배 품종은 금강밀이 주로 재배되었고 조경밀과 백중밀이 남부지역에서 재배 면적이 늘어나고 있다. 파종은 대부분 농가에서 10월 하순에서 11월 상순에 휴립광산파로 이루어지고 있으며, 시비는 2종 복합비료를 이용하여 평균 29.7 kg/10a이상 기비로 시용하였으며, 추비는 2월 하순~3월 상순에 질소비료를 1회 시용하는 농가가 주를 이루었는데, 농가 현장에서 표준시비량에 비해 과량의 비료가 시용되고 있기 때문에 적정 시비에 대한 관리가 필요하다. 재배 밀의 출수는 기상 영향으로 2011년은 5월 상순, 2012년은 4월 하순에 이루어졌으며, 밀 수확은 대부분 농가에서 6월 중순에 이루진 것으로 나타났다. 재배 면적 확대와 밀 재배 농가 소득 향상을 위하여, 수발아 및 붉은곰팡이병 저항성 증진과 기상이변에 대응할 수 있는 재해저항성 증진 품종 개발이 이루어져야하며, 국산밀 품질 향상을 위한 보급종 생산 및 확대가 필요하며, 지역별 밀 재배 농가의 규모화에 대한 지원과 재배 관리 체계 확립과 현장 지원 확대가 필요하다.

• Journal of Applied Biological Chemistry
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• 제55권4호
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• pp.253-261
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• 2012

PCDD/Fs 및 DL-PCBs는 농식품 잔류 유해물질 중 높은 생물독성 및 생물농축성으로 안전성 우려가 높아 많은 연구자들이 관심을 갖는 유해물질들이다. 하지만, 대부분의 오염조사연구는 지방함유량이 높은 육류 및 수산물을 중심으로 이루어지고 있어, 다소비 농산물인 곡류를 대상으로 한 다이옥신 잔류분석 연구결과가 부족하여 식이섭취를 통한 다이옥신류 노출평가를 수행하는데 어려움이 있다. 본 논문에서는 17종의 PCDD/Fs 및 14종의 DL-PCBs에 대하여 2010년산 쌀과 2011년산 보리에 대한 잔류 분석 및 이를 통한 한국인의 일일 섭취노출량을 조사하였다. 전국 8개 도에서 채취한 36점의 백미시료와 전남 및 전북에서 채취한 7점의 보리시료에 대한 잔류분석결과 백미 중 다이옥신류의 각 도별 평균 잔류량은 2.98-4.98 pg/g w.w.이었으며, 보리의 다이옥신류 평균 잔류량은 3.00-3.24 pg/g w.w.로 확인되었다. 쌀과 보리를 통한 국민 1인당 다이옥신 섭취노출량은 1.03 pg-TEQ/day/person와 0.0534 pg-TEQ/day/person 수준이었고, 이를 한국인 평균체중 55 kg을 기준으로 환산할 경우 Lower bound 시나리오의 경우 TDI대비 0.46와 0.03%였으며, Upper bound 시나리오의 경우 5.5와 0.18%로 국내산 쌀과 보리를 통한 다이옥신류 노출기여도는 미미한 것으로 판단된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.91-91
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• 2017

Drought is the most serious abiotic stress limiting rice production. However, little progress has been made in the genetic analysis of drought tolerance, because it is a complex trait controlled by a number of genes and affected by various environmental factors. In here, we screened 218 rice genetic resources for drought tolerance at vegetative stage and selected 32 highly drought tolerant varieties in greenhouse. Under rain-fed conditions, Grain yield of Nagdong was decreased by 53.3% from 517 kg/10a to 241 kg/10a when compare to irrigation condition. By comparison, grain yield of Samgang was decreased by 23.6% from 550 kg/10a to 420 kg/10a. The variety Samgang exhibited strong drought tolerance and stable yield in rain-fed conditions and was selected for further study. To identify QTLs for drought tolerance, we examined visual drought tolerance (VDT) and relative water content (RWC) using a doubled haploid (DH) population consisted of 101 lines derived from a cross between Samgang (a drought tolerance variety) and Nagdong (a drought sensitive variety). Three QTLs for VDT were located on chromosomes 2, 6, and 11, respectively, and explained 41.8% of the total phenotypic variance. qVDT2, flanked by markers RM324 and S2016, explained 8.8% of the phenotypic variance with LOD score of 3.3 and an additive effect of -0.6. qVDT6 was flanked by S6022 and S6023 and explained 12.7% of the phenotypic variance with LOD score of 5.0 and an additive effect of -0.7. qVDT11, flanked by markers RM26765 and RM287, explained 19.9% of the phenotypic variance with LOD score of 7.1 and an additive effect of -1.0. qRWC11 was the only QTL for RWC to be identified; it was in the same locus as qVDT11. qRWC11 explained 19.6% of the phenotypic variance, with a LOD score of 4.0 and an additive effect of 9.7. To determine QTL effects on drought tolerance in rain-fed paddy conditions, seven DH lines were selected according to the number of QTLs they contained. Of the drought tolerance associated QTLs, qVDT2 and qVDT6 did not affect tiller formation, but qVDT11increased tiller number. Tiller formation was most stable when qVDT2 and qVDT11 were combined. DH lines with both of these drought tolerance associated QTLs exhibited the most stable tiller formation. These results suggest that qVDT11 is important for drought tolerance and stable tiller formation under drought stress condition in field.