• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.340-345
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• 2001

High rates of nitrogen fertilization dangerously increase the nitrate content of vegetable crops, and the accumulation of nitrate in edible crops is undesirable because of potential risks to human health. Micronutrient solution containing Cu, Mn, Mo, Zn was tested for the suppression of nitrate accumulation in lettuce grown in pots treated with Mg fertilizer under a greenhouse condition. The micronutrient solution was sprayed on leaves at 3 and 4 weeks after transplanting of 20-day old seedlings. Plants were harvested after 5-week growth, and yield, contents of chlorophyll, sugar, micronutrient and nitrate, and also nitrate reductase activity were measured. Fresh weight of lettuce was significantly increased by the application of Mg and micronutrients, and the effect was the most significant in the Mg+micronutrient treatment. Also contents of chlorophyll and micronutrients were higher in the plants of micronutrient treatments. Contents of nitrate were reduced by about 14-18% in lettuce with Mg and/or micronutrient applications. Compared to the plants of control treatment, nitrate reductase activity was also higher in those plants treated with micronutrients, and in the treatment of Mg+micronutrients the enzyme activity was six times as high as that of control treatment. Although the effect of mineral nutrients on the suppression of nitrate accumulation in lettuce was relatively small in this study, an appropriate supply of mineral nutrients could be one of the solutions for the nitrate accumulation in vegetables.

• The Plant Pathology Journal
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• v.16 no.3
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• pp.156-161
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• 2000

A wilt disease occurred on greenhouse-grown eggplants at Yeojoo, Korea in 1997. The wilted eggplants had leaves with gradual yellowing, interveinal necrosis, and marginal crinkling. Vascular tissues of diseased stems were discolored, turned black, and microsclerotia developed at the base of stems. The disease progressed from lower parts of the plants upward. Fungal isolates from discolored vascular tissues were initially whitish to cream color on potato-dextrose agar (PDA) plate, which later turned black due to the formation of microsclerotia. Conidiophores were erect, hyaline, verticillately branched, and had 3 or 4 phialides arising at each node. Phialides were hyaline, arranged in whorls, and measured as 17.5-32.5 x 2-3$\mu\textrm{m}$. Conidia were hyaline, ellipsoidal to sub-cylindrical, mainly one-celled, and measured as 5-8.8 x 2-4$\mu\textrm{m}$. Conidia were borne in small clusters at the tips of phialides. Microsclerotia formed on PDA plates, and consisted of globular cells that formed irregular masses of various shapes. Chlamydospores were absent. Based on these cultural and morphological characteristics, the fungus was identified as Verticillium dahliae Klebahn. Pathogenicity tests by root cutting, root dipping or soil drenching resulted in similar symptoms observed in the naturally infected eggplants. This is the first report on occurrence of Verticillium wilt of eggplant in Korea.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.228-229
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• 2018

In the construction industry, we have set goals such as reduction of greenhouse gas emissions and reduction of energy use. In particular, reduction of CO₂ emissions in the concrete manufacturing process, reduction of industrial waste and industrial wastes into concrete The zero-emission level of reuse as a resource is under review. On the other hand, the cost of stone is expensive due to small quantity production of domestic stone production in order, it is difficult to carry and construct with heavy material, and it takes long time to construct. In order to solve the shortage of supply and demand of natural stone, various kinds of stone powder, artificial stone made by putting stone texture on the surface of mortar or concrete, fiber reinforced plate, tiles and the like are increasingly used. In this study, the artificial stone using slag and recycled aggregate instead of natural stone was fabricated and the strength characteristics were evaluated for its applicability and feasibility.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.4
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• pp.17-23
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• 2012

Due to reinforcement of international environment regulation and high oil prices, interest in renewable energy is growing. Countries participating in UNFCCC are continuously putting efforts in reducing greenhouse gas after enforcing Kyoto Protocol into effect on Feb, 2005. Energy used in buildings, which relies heavily on fossil fuel accounts for about 24% of total energy consumption. In this study, air, geothermal and water source heat pump systems for an 322 $m^2$ auditorium in an office building is simulated using TRNSYS version 17 for comparing energy consumptions. The results show that energy consumptions of air, geothermal and water source heat pumps are 14,485, 10,249, and 10,405 kWh, respectively. Annual equal payments which consider both initial and running costs become 5,734,521, 6,403,257 and 5,596,058 Won. Thus, water source heat pump is the best economical choice.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.211-214
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• 2008

Haploid system by anther culture allows the development of homozygous lines when doubled. The response of anther culture to Basta (glufosinate) resistance was investigated on transgenic plants (cv. Anjungbyeo) in order to identify inheritance of bar gene associated with Basta. Most of the regenerated transgenic plants were sterile, and only a few plants produced viable seeds ($A_1$) in the greenhouse. The bar gene was analysis by PCR in basta resistant transgenic plant ($TA_0$). The transgenic seeds ($A_1$) were significantly germinated in Basta solution compared with non-transformed seeds. As a result of anther culture, in regenerated haploid plants, segregation ratio was 1:1 in five of eight cross combinations. In diploid plants, segregation ratio was 1:1 in seven of eight cross combinations. Although there was some differences in the cross combinations, most of the combinations had 1:1 segregation ratio which supports the theory. The difference may be a result of the small sample size or the difference of anther culture response caused by genotypic difference. Hence, when many cross combinations were anther-cultured the results would support the theory.

• Nuclear Engineering and Technology
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• v.15 no.2
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• pp.110-116
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• 1983

The absorption and translocation of strontium-90 by soybean plant, Glycine max, was studied by applying strontium-90 solution on the foliage or on the soil surface right after the first flowering time under greenhouse conditions. The results are summarized as follows. In the foliar application of strontium-90, only a small portion of the radioactivity was translocated to other parts of the plant and most of it remained in the applied leaves, which should cause soil contamination after falling. In the soil surface application of strontium-90, much of the radioactivity was absorbed through the root and translocated to stems and leaves by different patterns depending on the growth stage.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8_spc
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• pp.1244-1255
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• 2019

Dairy goat production continues to be a socially, economically and culturally important part of the livestock industry in North, Central and South America and the Caribbean islands. Goat milk, cheese and other dairy products offer consumers food products with nutritional, health and environmental benefits. In North America, Mexico produces the greatest volume of goat milk, but most is for family or local consumption that is typical of a mixed farming system adopted by subsistence farmers in dry areas. The United States is not yet a large global goat milk producer, but the sector has expanded rapidly, with dairy goat numbers doubling between 1997 and 2012. The number of dairy goats has also increased dramatically in Canada. Commercial farms are increasingly important, driven by rising demand for good quality and locally sourced goat cheese. In South America, Brazil has the most developed dairy goat industry that includes government assistance to small-scale producers and low-income households. As of 2017, FAO identified Haiti, Peru, Jamaica, and Bolivia as having important goat milk production in the Western Hemisphere. For subsistence goat producers in the Americas on marginal land without prior history of chemical usage, organic dairy goat production can be a viable alternative for income generation, with sufficient transportation, sanitation and marketing initiatives. Production efficiency, greenhouse gas emission, waste disposal, and animal welfare are important challenges for dairy goat producers in the Americas.

• Korean Journal of Organic Agriculture
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• v.29 no.3
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• pp.333-358
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• 2021

This study investigates consumers' purchasing behavior and perception of the low-carbon certificated agricultural product. To this end, we surveyed 1,000 consumers and the main findings are as follows. First, Even after six years of national certification, it is important to promote the low-carbon certification system due to insufficient awareness and purchase experience. Second, the certificated area is small at around 5% of the area of environment-friendly agricultural products and GAP certification, and certification is concentrated on fruit trees. Third, an appropriate level of high-priced strategy can be useful considering the cost of low-carbon certification, image management of low-carbon certificated agricultural products, and quality is the most important factor for consumers to consider when purchasing fresh agricultural products. Fourth, consumers recognized that the contribution of low carbon certification in reducing greenhouse gas emissions and preserving the environment was higher than that of environment-friendly agricultural products or GAP certification. Considering that, promotional activities linked to environment-friendly agricultural products and GAP certification may be effective when promoting low-carbon certification. Finally, the Ministry of Agriculture, Food and Rural Affairs is implementing a carbon point system linked to Green Card to revitalize low carbon certification, but 25.7% of consumers are aware of it, and 8.4% have little experience in issuing it.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.5
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• pp.598-606
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• 2022

With the advancement of industry, the use of various sustainable energy sources and solutions to problems affecting the environment are being actively requested. From this point of view, it is intended to directly burn unused biogas to use it as energy and to solve environmental problems such as greenhouse gases. In this study, a new type of cavity matrix combustor capable of low-emission complete combustion without complex facilities such as separation or purification of biogas produced in small and medium-sized facilities was proposed, and CFD numerical calculation was performed to understand the performance characteristics of this combustor. The cavity matrix combustor consists of a burner with a rectangular porous microwave receptor at the center inside a 3D cavity that maintains a rectangular parallelepiped shape composed of a porous plate that can store heat in the combustor chamber. As a result of numerical calculation, the biogas supplied to the inlet of the combustor is converted to CO and H₂, which are intermediate products, on the surface of the 3D matrix porous burner. And then the optimal combustion process was achieved through complete combustion into CO₂ and H₂O due to increased combustibility by receiving heat energy from the microwave heating receptor.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1288-1294
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• 2022

Hydrogen as an environmentally friendly energy carrier has received special attention to solving uncertainty about the presence of renewable energy and its dependence on time and weather conditions. This material can be prepared from different sources and in various ways. In previous studies, fossil fuels have been used in hydrogen production, but due to several limitations, especially the limitation of the access to this material in the not-too-distant future and the great problem of greenhouse gas emissions during hydrogen production methods. New methods based on renewable and green energy sources as energy drivers of hydrogen production have been considered. In these methods, water or biomass materials are used as the raw material for hydrogen production. In this article, after a brief review of different hydrogen production methods concerning the required raw material, these methods are examined and ranked from different aspects of economic, social, environmental, and energy and exergy analysis sustainability. In the following, the current position of hydrogen production is discussed. Finally, according to the introduced methods, their advantages, and disadvantages, solar electrolysis as a method of hydrogen production on a small scale and hydrogen production by thermochemical method on a large scale are introduced as the preferred methods.