• Current Research on Agriculture and Life Sciences
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• 제31권2호
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• pp.75-82
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• 2013

Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

• 한국어병학회지
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• 제25권1호
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• pp.59-65
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• 2012

인공종묘 생산 철갑상어 사육과정에 복부팽만을 특징으로 하는 질병이 발생하였다. 병어는 위와 소화관의 가스의 이상 축적에 의한 것으로 특히, 위의 분문부에서의 가스 축적이 현저하기 때문에 이상 유영을 하다가 폐사하게 된다. 병어의 위, 양어지의 배출수와 잔사에서는 원인체로 추정되는 Candida sp.가 검출되었다. 먹이와 함께 섭취된 Candida가 대사 과정 중에 발생하는 가스가 위에 축적됨으로서 위가팽창하게 되고, 일부는 식도와 부레로 이동한 것으로 생각된다.

• 한국유기농업학회지
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• 제21권1호
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• pp.1-18
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• 2013

Animal and crop production systems were integrated on a single farm. This integrated farming system recycled nutrients on the farm. The separation of animal and crop production with the introduction of cheap commercial fertilizers, farms were not used land-applied manure. The on-line manure matching is one of the emerging business in the achievement of recycling and resource recovery. The manure matching actively promotes the reuse and recycling of by-products and manure. This study constructs to manure matching information system to solve the exchange problems between herders and croppers. Manure matching web sites designed. This paper introduces a web-based animal manure matching system. A manure matching service, part of the manure transport, links farmers who produce excess manure with farmers who can use the manure. Farmers registered with the service have requested manure. The manure matching service supports the transport project by linking farmers with excess manure with those farmers who can utilize the manure safely as a nutrient source. The goal of the service is to protect water quality by fostering efficient land application. Benefits to those who use the manure network include reduced disposal costs, lower purchase costs and recycling of manure. The manure matching is based on the principle that 'one persons waste is another person's fertilizer.' It provides a free online matchmaking service for environmentally safe manure recycling management system.

• Journal of Plant Biology
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• 제15권s호
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• pp.33-49
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• 1972

Recently two thousand year old several villages ruins discovered at Amsadong, Daeshimli and Hunbaukol near the Han River side in Korea. An investigation of the present flora of these three localities was done. There are 84 families including 419 species of vascular plants. The vegetations of flora in the localities of the Han River side are very similar. the forests are poorly developed and appear as the secondary vegetations. The reforest plants can be recognized as Pinus rigida, quercus acutissima, Q. serrata, Robinia pseudoacacia and Alnus hirta. Herbaceous plants of Miscanthus sacchariflorus and Phragmitis japonicus bind up the soiles of the Han River side. Populus nigra grows abundantly in the moist places of sand bars which are located on the river side south of Daeshimli and on the northern side of the Han River across from Hunbaukol. These three area are fully cultivated but still many primitive farm techniques are employed. Farm produce crops include rice, corn, barley wheat, other vegetables, and a few ornamental plants. In this study the author found flower color variations ranging from a dark blue to a pale blue, and chromosome number differences existing between the populations of Commelina communis. The dark blue flowered taxa chromosome number is 44 and in the pale blue taxa it is 72. The wild white flowered Chrysanthemum is Chrysanthemum zawadskii Herb. ssp. acutilobum and which has finely lobed leaves, and has 54 chromosome in the root tip cells.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.198-198
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• 2017

Climate change causes unpredictable and erratic climatic patterns which affects crop production in agriculture and threatens public health. To cope with the challenges of climate change, sustainable and sound growth environment for crop production should be secured. Recent attention has been given to the development of smart irrigation system using sensors and wireless network as a solution to achieve water conservation as well as improvement in crop yield and quality with less water and labor. This study developed the smart irrigation technique for farmlands by monitoring the soil moisture contents and real-time climate condition for decision-making support. Central to this design is micro-controller which monitors the farm condition and controls the distribution of water on the farm. In addition, a series of laboratory studies were conducted to determine the optimal irrigation pattern, one time versus plug time. This smart technique allows farmers to reduce water use, improve the efficiency of irrigation systems, produce more yields and better quality of crops, reduce fertilizer and pesticide application, improve crop uniformity, and prevent soil erosion which eventually reduce the nonpoint source pollution discharge into aquatic-environment.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권1호
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• pp.50-56
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• 2010

Oil contamination soil has been one of the most environmental social issues for decades in the inside and outside of country. The law of soil environmental preservation was carried out in the 1990s and the government controlled not only soil environment management and the remediation of contaminated soil but also promoted the development of remedial technology and cleanup business of contaminated soil by national policy. In addition to agriculture areas, the main oil contaminated sites are a gas station, oil reservoir, petro-chemical complex, site of railway carriage base and military camp. The contamination-frequency of agriculture area and effect sites are low but it has significantly important area on account of producing food for human beings. Therefore, we should be concerned about oil contamination damage of agriculture area. The oil contamination damage of agriculture area influenced drop of birth and breeding since the oil directly adheres to seeds and farm products even diffusion of contaminated soil to cultivation area. The studies of the crops and the food vegetation has not enough detailed data caused by the incident of oil contamination. This study investigated the effect of oil in germination and growth of selected plant seeds. In this study, we try to verify whether the oil contamination by accidents on farmland influenced the damage of farm produce and the mutual relation both oil contaminated soil or the vegetation of crops. The impact of oil on plant development was followed by phytotoxicity assessments. The plants exhibited visual symptoms of stress, growth reduction and perturbations in developmental parameters. The increase of the degree of pollution induced more marked effects in plants, likely because of the physical effects of oil. The relationships between the phytotoxicity contents of plants and growth reduction suggest a chemical toxicity of fuel oil. In addition, while cleaned up the contaminated soil under the standard of contaminated soil we examined it was suitable for region standard and it may have practical possibility for fill material of construction of afforestation and molding soil of landfill.

• 농촌지도와개발
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• 제21권1호
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• pp.83-115
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• 2014

본 연구는 대형유통업체의 PB사과 상품에 대한 소비자들의 지각수준에서 브랜드신뢰와 구매의도에 영향을 미치는 요인을 밝혀서 대형유통업체의 PB사과 상품 확대에 대응하는 농업 경영체 및 산지 생산농가의 마케팅 전략의 시사점을 제시 하고자 하였다. 분석결과, PB사과 상품의 품질수준은 브랜드신뢰에 영향을 미치고, 품질수준과 지각가치, 브랜드신뢰가 구매의도에 영향을 주었다. 그러나 브랜드이미지는 브랜드신뢰와 구매의도에 영향을 미치지 않았다. 이에 따른 전략적 시사점은 첫째, NB 사과의 전통성을 강조하여 품질수준에 대한 인식형성이 이루어질 수 있도록 해야 한다. 둘째, 소비자들의 구매의욕을 일으킬 수 있는 감성적 포장디자인과 다양한 구성의 상품개발이 필요하다. 셋째, NB사과에 대한 소비자들의 지각가치 향상을 위해서 NB사과 상품구매의 편리성제공으로 지각가치를 향상 시켜야 한다. 넷째, 생산자 단체와 소비자단체의 지속적인 연계활동을 통하여 NB사과 상품에 대한 브랜드 신뢰도를 향상 시켜야 한다.

• 한국가금학회지
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• 제26권1호
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• pp.43-50
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• 1999

The features of special brand eggs are growing more and more diverse and it is hard to draw a clear distinction between these and ordinary (no-brand) eggs. Special brand eggs range from those with objectively recognizable characteristics to those given only an unsubstantial product image and price differentials are among them great, too. The relation between product features and prices is unclear. Special brand eggs are the commodity whose characteristics are the vaguest of all livestock products. Farm's brand eggs produce a high profitability to producers is they are directly sold to consumers, by, for example, home-delivery service. But if they are sold to supermarkets, etc., producer's (poultry farmer's) income becomes lower by the amount of distributors' margin, reducing the profitability substantially. Thus how to increase the ration of retailing is important for farmers to secure a high profit. The sales strategies of poultry are the combination of two elements, that is, new product development (product differentiation) and creation of new market. But it is difficult for special brand egg producers to develop products with clear characteristics (use value) distinct form ordinary eggs and so these producers depend on the factors of appearance, such as the color of egg shells and package. Special brand eggs manage to keep their marketable value by the combination of the few product features and product image. Thus NB eggs from feed producers have a great market-ability since they can take advantage of the power of patents and TV commercials. However, market differentiation affects profitability much more than product features and price gaps are very wide between directly sold and wholesaled eggs. The producers of special brand eggs have come to the turning point where they have to decide whether they will content with being the subcontractors for NB and PB eggs or they will continue to keep their independence in production and marketing.

• 한국환경과학회지
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• 제10권5호
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• pp.365-371
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• 2001

The optimum dosage of quicklime in producing organic fertilizer using livestock wastes vith a greater than 80% water content was analysed. After one day had elapsed to allow for the organic fentilizer to dry, the quicklime dosage and the composition of the organic fertilizer were analysed. Any from done to the organic fertilizer was also assessed. The amount of the quicklime required to stabilize livestock wastes was determined by water content of livestock wastes. For J farm(slurry style) of which livestock wastes have 94.6% of water concentration, less than 3% of total amount of livestock wastes, for H farm (scraper style) of which livestock wastes have 85% of water concentration, less then 4% of total livestock wastes and Y farm(traditional style) of which livestock wastes have 80% of water concentration, less then 5% of total livestock wastes. Generally, in order to pack the organic fertilizer, water containing quicklime0stabilized livestock wastes should be less than 35%. It takes 9 days to keep this water content for the wastes from H and Y farms(less than 85% in water content), and 12 days for the wastes from J (94.6% in water content). According to the classification standard for compost constitution by Higgins, the crude fertilizers from all 3 farms had high grade $K_2O$ and CaO, the middle grade T-N and middle or low grade $P_2O_5$. Stabilization by quicklime is known to inhibit bacterial decomposition of organic matter and the activity of pathogenic organisms. In this study, more then 99.99% of coliform group, fecal group and viable cell count were reduced. Our results indicate that livestock wastes of greater 80% water content could be used to produce organic fertilizer without the addition of a material for moisture control.

• 한국산학기술학회논문지
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• 제16권4호
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• pp.2737-2743
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• 2015

풍력발전은 풍력단지가 전력계통과 접속되는 모선의 전압을 유지 또는 제어하기 위한 충분한 무효전력을 공급할 수 있어야 한다. 하지만 풍력단지와 계통 접속점(POI - Point of Interconnection) 모선을 연결하는 선로의 무효전력 손실 때문에 풍력터빈의 무효전력공급은 접속점의 전압을 제어하기에는 불충분하다. 이 문제는 접속점에 STATCOM(Static Synchronous Compensator)과 같은 부수적인 무효전력 보상장치를 설치하여 해결할 수 있다. 본 논문에서 제시하는 STATCOM과 Switched-Shunt, 탭변환 변압기와 같은 기존의 무효전력 보상장치의 협조제어를 사용하면 더욱 효과적으로 접속점 모선의 전압을 제어할 수 있다. 본 논문에서 제시한 방법을 이용하여 초기부하에 대하여 임의의 부하 변동률을 가지는 모의 시스템에 적용한 결과 접속점 모선의 전압강하는 60%이상 개선되었고 부하 모선의 전압은 정격전압의 95%이상을 유지하였다.