• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.411-416
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• 2002

The effects of electrodialysis (ED) alone or ED plus ultrafiltration (UF) on deacidification of mandarin orange juice were studied by using a commercial ED stack with ion exchange membranes. ED processing, reduced the total acidity of the juices by 30% (0.6~0.7% as total acidity) after 50 min and by about 60~70% (0.23~0.4% as total acidity) after 100 min, as compared to the control juice. However, the acidity reduction after 50 min of ED was determined to be suitable, when considering total acidity (0.6~0.7%, w/w) and current efficiency. There was no color change in the juices following ED, and the pH and Brix were only slightly decreased. Furthermore, ascorbic acid and citric acid concentrations showed only minor decreases, and amino-N, free sugar, and flavonoid contents remained almost unchanged. Therefore, we concluded that the nutritional integrity of the juice was maintained. ED combined with UF may be effective, not only in preventing membrane fouling, but also in preserving the nutrients, such as ascorbic acid, in citrus juice.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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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.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.2
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• pp.132-137
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• 2015

Effects of chitin and chitosan treatments on soil microorganisms and the mesofauna were investigated in a microcosm and a fumigated field experiment. Responses of microorganisms were determined using microbial phospholipid fatty acid (PLFA) analysis, whereas responses of the mesofauna were measured in terms of the abundances of nematodes and microarthropods. Soil nitrate concentration increased on the application of chitin. Overall, chitin promoted bacterial and fungal abundance, leading to an increase in abundance of free-living soil nematodes that feed on decomposers. The ratio of saturated to unsaturated fatty acids was highest in the chitin-treated soil. Chitosan had a minimal effect on the abundance of microorganisms; however, it reduced the abundance of collembolans in the microcosm experiment. These results indicate that the application of chitin has beneficial effects on the supply of nutrients and promotion of the abundance of soil organisms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.581-585
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• 1985

This study was carried out with blue mussels at Otsuchi Bay in Japan from August 1981 to May 1982, in order to investigate the effect of the parasitic pea crab (Pinnotheres pholadis) on the reproductive capacity of host blue mussels (Mytilus edulis galloprovincialis). The results show that pea crabs delay gonad development of host mussels about one month and lower their fatness rate by intercepting nutrients. The parasitization with pea crabs is thought not to prevent spawning activity itself, but to reduce the number of germ cell resulting in the reduced space of gonads.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.701-710
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• 1996

Composting has gained rapid acceptance as a method of recyling relatively dry organic materials such as leaves and brush and , when alternative disposal costs are high, even moist materials such as grass clippings and dewatered sewage sludges. However, as moisture contents rise above 60% , the need for a dry bulking amendment increase the costs of composting , both by direct purchases of amendment and though increased reactor capacity and materials handling requirements. High moisture materials also present increased risks of anaerobic odor formation through reduced oxygen transport (Miller , 1991) . These costs and operational challengers often constrain the opportunities to compost high moisture materials such as agricultural manures. During the last several decades economies of scale in livestock production have been increasing livestock densities and creating manure management challenges throughout the world. This issue is particularly pressing in Korea, where livestock arms typically manage little or no cropland, and the nutrients and boichemical oxygen demand in manure pose a serious threat to water quality. Composting has recently become popular as a means of recycling manure into products for sale off the farm, but bulking amendments (usually sawdust) are expensive designed to minimize bulking agent requirements by using the energy liberated by decompostion. In this context the composting reactor is used as a biological dryer, allowing the repeated use of bulking amendment with several batches of manure.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.719-725
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• 2019

To recover the discoloration of Pyropia yezoensis, additional NO₃^- and PO₄^3- nutrients were supplied to the discolored blades. As a result, the efficiency of photosynthesis was increased from two days after incubation with NO₃^- and five days after incubation with PO₄^3-. In addition, the chromaticity analysis results showed significant changes. Furthermore, the cell vacuoles bloated due to discoloration were reduced again when they were restored from discoloration, suggesting that the control of discoloration is feasible by nutrient supply.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.1
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• pp.48-54
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• 1990

In order to investigate effects of starch addition on the fermentative quality and dry matter digestibility (DMD) of Kudzu, Puerarie thunbergii Bentham plants were ensiled by the conventional method in small experimental plastic silo of 7.5 liter with different levels of starch addition. The fermentative quality, neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) of silage were determined by chemical analysis, and in vitro dry matter digestibility (DMD) by pepsin-cellulase technique. Total digestibile nutrients (TDN), digestible energy (DE) and metabolizable energy (ME) were calculated with DMD. The results obtained were as follows; 1. Acetate, butyrate, PH, NDF, ADF, and ADL of Kudzu silage were reduced with increasing of starch addition but the contents of lactate and total acid were increased. 2. The DMD was marked 47.5, 49.5, 51.2, 57.9 and 62.0 % under starch addition with a rate of 0, 2, 4, 6 and 8 %, respectively. 3. TDN, DF and ME were increased with high rate of starch addition. 4. The regression equation and correlation of Kudzu silage between level of starch (X) and DMD (Y) were Y= 41.6 + 1.86 X (I= 0.96, P < 0.01), of silage between Flieg's score (X) and DMD (Y) were Y= 41.6 + 0.23 X (I= 0.96, P < 0.01) and of silage between level of starch (X) and Flieg's score (Y) were Y= 21.3 + 7.97 X (I= 0.97, P < 0.01), respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.2
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• pp.108-115
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• 2017

The aim of this study was to evaluate different herbicides in corn-soybean intercropping for optimum growth, yield and nutritive value of forage under Korean environment conditions. Herbicidal treatments were randomly applied over five plots, viz. (1) Control treatment: no herbicide; (2) Alachlor; (3) Simazine; (4) Pendimethalin and (5) Mixture of alachlor and simazine herbicides in RCBD have three replications. Results depicted that treated herbicides exhibited significant effect over control of weeds. Simazine herbicide alone or mixed with alachlor had adverse effects on soybean but enhanced (p<0.05) corn production in terms of survivability, dry matter and digestible nutrients yield. Corn-soybean coupling and total dry matter yield were greater (p<0.05) in pendimethalin. Simazine-alachlor mixture reduced (p<0.05) soybean height. Conclusively, simazine could not be suitable for corn soybean intercropping because of having an adverse effect on soybean component. Pendimethalin could maintain growth and yield of corn and soybean both components. Effect of alachlor was comparable to that of pendimethalin.

• Environmental Engineering Research
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• v.24 no.4
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• pp.582-590
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• 2019

Currently, the waterfront facility was constructed in New Songdo City, South Korea. It has the various water leisure areas and especially an artificial urban canal with filtered seawater by re-circulating flow system. However, due to excessive amount of nutrients from seawater combined with complicated geometry, it is highly vulnerable to deterioration of water quality. In this study, flow characteristics and pollutant transport were analyzed with comprehensive numerical models, MIKE 3 FM and ECO-lab. Based on these numerical results, notable sampling points were selected for field measurements and comparison between modeling and measured results were conducted. In addition, the integrated water quality evaluation index, Water Quality Index was applied to analyze various water quality issues. We also set up scenarios to control the two kinds of water quality factors, dissolved oxygen (DO), and total phosphorus (TP). As a result, the effect of 20% reduction of TP was less than 10% and it was almost ineffective for a year but it was reduced by up to 40% in case of scenario which DO is increased by 20%. Therefore, it was recommended to control the DO concentration, usually by applying re-aeration facility, rather than TP in artificial urban canal with seawater.

• Journal of Environmental Science International
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• v.12 no.9
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• pp.957-966
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• 2003

Gunsan coastal area is one of region increasing pollution problems. To improve water quality, the reduction of these nutrients loads should be indispensible. In this study, the three-dimensional numerical hydrodynamic and ecosystem model were applied to analyze the processes affecting the eutrophication. In field survey, the average concentrations of dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus(DIP) at surface waters were found to be 0.43mg/$\ell$ and 0.03mg/$\ell$ respectively, which were exceeding second grade of water quality criteria. In hydrodynamic modelling, the comparison between the simulated and observed tidal ellipses showed fairly good agreement. The ecosystem model was calibrated with the observed data in study area. The simulated results of DIN were fairly good coincided with the observed values within relative error of 32.39%, correlation coefficient(r) of 0.99. In the case of DIP, the simulated results were fairly good coincided with the observed values within relative error of 24.26%, correlation coefficient(r) of 0.82. The simulations of DIN and DIP concentrations using ecosystem model were performed under the conditions of 20∼80% reductions for pollutant loading. At simulation results, concentration of DIN and DIP were reduced to 20∼80% and under 10% in case of the 80% reduction of pollutant loading, respectively.