• Nuclear Engineering and Technology
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• 제56권3호
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• pp.819-823
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• 2024

The main criteria used in NEI 18-04 to define SSCs as risk-significant include (1) the SSC is required to keep all LBEs within the F-C target, and (2) the total frequency with the SSC failed exceeds 1% of the limit for at least one of the three cumulative risk metrics used for evaluating the integrated plant risk. The first one is a reasonable criterion in determining the risk significant SSCs. However, the second criterion may not be adequate to serve the purpose of determining the risk significance of SSCs. In the second criterion, the cumulative risk metric values representing the integrated plant risk (less the preventive and mitigative effects of the SSC being evaluated) are compared to a risk limit that represents a very small contribution to the overall integrated plant risk, which corresponds appropriately to the contributions from individual SSCs. The easiest approach to redefine the NEI 18-04 definition of risk-significant SSCs in relation to the integrated plant risk metrics is to compare the difference, between the risk metric value calculated with the SSC failed and the risk metric value calculated with the SSC credited, with 1% of the risk limit established for the integrated plant risk metrics.

• 한국응용곤충학회지
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• 제17권2호
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• pp.75-80
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• 1978

본 시험은 애멸구의 MEP제에 대한 저항성이 유전적 특성에 기인된 것인지를 알아보기 위하여 나주지역의 야외집단을 채집하여 감수성인 실험실 계통과 교배하고 $F_1,\;BC_1F_1$ 및 $F_3$에 대하여 Probit 법으로 분석하고 $LD_{50}$을 비교한 결과는 다음과 같다. 1. 나주지역의 애멸구 야외집단은$LD_{50}$이 자충충의 경우 0.0029ug/충으로 감수성인 실험실계통의0.0008ug/충에 비하여 저항성의 차를 타나내었다. 2. 나주지역 야외집단이 나타내는 저항성은 $F_1$과 $BC_1F_1$ 의 분석에서$LD_{50}$ 및 사충율의 회귀가 저항성인 친쪽으로 가깝게 나타나는 경향을 보여 유전적 특성에 기인된다고 생각되었다. 3. $F_2$ 집단의$LD_{50}$은 양친의 중간 정도였으며 넓은 분산을 보이고 있어 MEP제에 대한 저항성의 유전은 수개의 유전자가 관여할 것으로 생각되었다.

• 한국초등과학교육학회지:초등과학교육
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• 제28권3호
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• pp.277-291
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• 2009

This study is intended to develop plant inquiry instruction using Rapid-cycling Brassica rapa (RcBr) whose life cycle is relatively short, and to apply it to the elementary science instruction of the 4th grader and examine their plant concept, science inquiry skills and science-related attitudes. The materials were consisted of laboratory manuals for the students as well as teachers' guide. By observing the life cycle of RcBr, students can experience the conceptual learning of the plant's life cycle. In addition, this study investigated the cause of change in science inquiry skills and science-related attitudes by interviewing 12 students. It has shown that plant inquiry instruction using RcBr has meaningful effects on students' understanding of the plant concept, improving students' science inquiry skills, and changing students' science-related attitudes. Students who showed improvement in science inquiry skills were able to answer questions regarding science knowledge correctly. And students whose science related attitudes were improved had a positive attitude on cultivating RcBr. Students told that RcBr was an interesting and good material to inquire plant. Because of its small size and its relatively short life cycle of RcBR, it should be a desirable plant material for the inquiry instruction which can give rise to useful and meaningful results for the elementary school students.

• Molecules and Cells
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• 제28권2호
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• pp.131-137
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• 2009

Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

• 융합보안논문지
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• 제16권7호
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• pp.173-180
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• 2016

국내에서 공장자동화에 대한 관심이 증가하고 있으며, 이에 관한 개발이 활발하게 시도되고 있다. 특히, '제조업 혁신 3.0 전략'에 따라 중소기업의 제조 공장들에 대한 스마트화에 대한 관심이 급격히 증가하고 있다. 뿐만 아니라, 스마트 공장을 구축하기 위한 정책적, 기술적, 전략적 접근 방법을 모색하고 있다. 하지만 이와 같은 스마트 공장 또는 공장 자동화 시스템을 도입하기 위해서는 제조 공장이 갖는 보안 취약점과 개인정보 보호 문제는 반드시 선결해야만 한다. 그러므로 우리는 공장 자동화를 위해서 가장 많이 도입되고 있는 무선 통신 기술인 RFID 통신 프로토콜에 적용 가능한 경량 암호 프로토콜을 제안한다. 본 논문에서 제안한 경량 암호 프로토콜은 기존의 공개키 기반 시스템이나 대칭키 암호 알고리즘과 비교해서 연산 횟수가 적고 처리 속도가 빠르다. 뿐만 아니라 낮은 전력 소비량과 저장 공간을 소비하도록 설계하였다.

• 환경생물
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• 제37권2호
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• pp.144-154
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• 2019

경주시 사적지, 도시공원지역, 그리고 하천 86개소의 현지조사를 통하여 귀화식물을 조사한 결과 21과 59속 78종 1아종 5변종으로 총 84분류군으로 조사되었다. 이중 사적지는 68분류군, 근린공원 43분류군, 하천 59분류군, 소공원 42분류군 등으로 나타났다. 출현식물 중 널리 분포하나 개체수는 많지 않은 귀화도 3등급 분류군이 31.0%, 널리 분포하고 개체수도 많은 5등급이 29.8%, 국지적으로 분포하고 개체수도 많지 않은 분류군인 2등급이 20.2% 등으로 나타났다. 생태계교란식물은 미국쑥부쟁이, 가시상추, 애기수영 등 7분류군으로 가시상추는 41.9%로 가장 빈번하게 출현하였고, 미국쑥부쟁이는 34.9%로 하천변에서, 애기수영은 25.6%로 사적지나 소공원 일원에서 빈번하게 출현하였다. 생태계교란식물의 확산을 방지하기 위해서는 지속적인 모니터링이 필요하며, 특히, 정착초기에 물리적 제거나 토양의 대체 등 관리 계획이 필요하다.

• 한국식물병리학회지
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• 제14권5호
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• pp.452-457
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• 1998

Thirty-eight isolates of Phytophthora sp. caused rots on roots and basal stems were collected from five flowering plants from 1992 to 1997 at eight cultivation areas in Korea. All the isolates were identified as P. nicotianae based on following characteristics. The fungus produced markedly papillate, not caducous and ovoid to spherical sporangia, abundant chlamydospores, and small oospores with amphigynous antheridia only when paired with either A1 or A2 mating type. All isolates grew well at 35$^{\circ}C$ and showed distinct arachnoid colony patterns on CMA and PDA. Sizes of sporangia and chlamydospores of five representative isolates from each plant averaged 43-52$\times$30-38 ${\mu}{\textrm}{m}$ and 28 ~34 ${\mu}{\textrm}{m}$. Mating type of the isolates was either A1 or A2, and oogonia and oospores were measured as 28~31 ${\mu}{\textrm}{m}$ and 21~25 ${\mu}{\textrm}{m}$. PCR-RFLP analysis of rDNA of the five isolates resulted that restriction band patterns of the small subunit and ITS regions were identical to a perilla isolate of P. nicotianae, but distinct from P. cactorum and P. capsici. Cross inoculation tests showed that the five isolates had pathogenicity to lily, christmas cactus, anthurium, baby's breath and carnation with different degrees. However, each isolate showed stronger pathogenicity to its corresponding original host than others. Among five lily cultivars Georgia and Quririna were more susceptible than Napoli and others. This is first report of Phytophthora root and stem rot of lily, Christmas cactus, anthurium, baby's breath and monochoria in Korea.

• 한국압력기기공학회 논문집
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• 제4권2호
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• pp.13-19
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• 2008

In order to predict a remaining life of a plant, it is necessary to select the components that are critical to the plant life. The remaining life of those components shall be evaluated by considering the aging effect of materials used as well as numerous factors. However, when evaluating reliability of nuclear structural components, some problems are quite formidable because of lack of information such as operating history, material property change and uncertainty in damage models. Accordingly, if structural integrity and safety are evaluated by the deterministic fracture mechanics approach, it is expected that the results obtained are too conservative to perform a rational evaluation of plant life. The probabilistic fracture mechanics approaches are regarded as appropriate methods to rationally evaluate the plant life since they can consider various uncertainties such as sizes and shapes of cracks and degradation of material strength due to the aging effects. The objective of this study is to evaluate the structural integrity for a reactor pressure vessel under the small break loss of coolant accident by applying the deterministic and probabilistic fracture mechanics. The deterministic fracture mechanics analysis was performed using the three dimensional finite element model. The probabilistic integrity analysis was based on the Monte Carlo simulation. The selected random variables are the neutron fluence on the vessel inside surface, the content of copper, nickel, and phosphorus in the reactor pressure vessel material, and initial RTNDT.

• 한국식품과학회지
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• 제35권5호
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• pp.757-763
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• 2003

L-Arabinose inhibits intestinal sucrase in an uncompetitive manner and, consequently, inhibits the absorption of sucrose from the small intestine. The addition of $3{\sim}5%$ L-arabinose to sucrose causes about a 60% reduction in the digestion of sucrose in the small intestine. In addition, it reduces the increase of the levels of blood sugar, insulin, triglycerides, and cholesterol caused by the ingestion of sucrose. The taste of L-arabinose is quite similar to that of sucrose, with approximately 50% the sweetness of sucrose. Naturally occurring arabinose is an L-form and a noncaloric sugar that is not metabolized in animals. L-Arabinose is a common component of plant cell walls and is widely distributed in the plant kingdom. It is the main component of cereal hemicellulose, such as corn, wheat, and rice, pectic substances of beet, apple pulps, and some plant gums. L-Arabinose can be produced by either the acid hydrolysis or the enzymatic hydrolysis of some plant gums, corn fiber, and beet pulps. This novel sugar has a potential to be used as a food additive for improving obesity and maintaining good health.

• Journal of Applied Biological Chemistry
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• 제42권3호
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• pp.140-145
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• 1999

Livestock manure is generally beneficial to soil and crop production when appropriate amount is applied, but excessive application may be detrimental to soil and water environments. A proper protocol of livestock waste treatment is required to manage the quality of soil and water. A trickling filter system using rice straw media was employed to treat piggery wastewater from small-scaled livestock farms as an alternative to the currently available methods. Batches of piggery wastewater were treated with this system, and the byproducts of rice straw media and trickling filtrate were applied to the soil with cultivating rye (Secale cereale L.). Objective of this research was to characterize these byproducts for the sustainable soil amendments and rye production. Both the treated straw medium and filtrate were proven to be effective organic fertilizers for rye plant development, with the enhanced but balanced absorption of nutrients. The synergistic effects of filtrate in addition to straw application did not show, but the filtrate appeared to lead to a higher water content of the plant. No specific nutrient deficiency or toxicity symptom was shown due to the salts derived from the byproducts applied. Chemical parameters of the soil quality were significantly improved with the application of straw medium either with or without the filtrate. Judging from parameters relating to the salt accumulations, such as sodium adsorption ratio (SAR), electrical conductivity (EC), exchangeable sodium percentage (ESP), potassium adsorption ratio (KAR), and residual P concentrations, the byproducts from piggery wastewater exhibited no detrimental effects on soil quality within the ranges of treatments used. In addition to the effectiveness of the rice straw trickling filter system for the small-scaled swine farms, both rice straw medium and filtrate could be recycled for the sustainable soil amendment and plant nutrition.