• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.389-393
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• 2001

For an effective utilization, quality stability of instant powdered oyster soup made of canned oyster processing waste water (IPSW) was determined. Instant powdered soup from oyster hot-water extracts (IPSE) was also prepared by mixing hot-water extract powder (15 g) with table salt (5 g), cream powder (19 g), milk replacer (12 g), wheat flour (20 g), corn flour (15 g), starch (5 g), glucose (7.5 g) and onion powder (1.5 g). In preparing IPSW, mixed powder from wash water and boiling liquid waste, instead of powder from hot-water extracts and table salt, was added (powder from boiling liquid waste: powder from wash water= 12: 8) and other additives were added in proportion to those in the IPSE. The moisture content, water activity, peroxide value and fatty acid composition showed little changes during storage of the IPSW. The pH, volatile basic nitrogen content and brown pigment formation increased slightly, while white index decreased slightly during storage of IPSW. No significant difference was observed in the changes of food component during storage between IPSW and IPSE. According to a sensory evaluation, the change in quality of IPSW was negligible during 12 months of storage. from the results of the chemical experiment and sensory evaluation, IPSW packed with laminated film bag (OPP, $20{\mu}m/PE,\;20{\mu}m/paper,\;45g/m^3/PE,\;20{\mu}\;m/Al,\;7{\mu}\;m/PE,\;20{\mu}m$) was revealed to be preserved in good quality during 12 months of storage.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.184-194
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• 2021

Since the construction of a dike in 1983, the water quality in the Bunam Lake has continued to deteriorate due to algal bloom caused by agricultural nutrient loading. Therefore, we evaluated the change in water quality and phytoplankton ecological characteristics in Bunam Lake and Cheonsu Bay, Korea. Water temperature, salinity, dissolved oxygen, chemical oxygen demand (COD), chlorophyll, and phytoplankton community were surveyed in April during the dry season and in July during the rainy reason. As a result, during the dry period, phytoplankton proliferated greatly and stagnated in the Bunam Lake while a very high population of cyanobacteria Oscillatoria spp. (8.61×10⁷ cells L^-1) was recorded. Most of the nutrients, except, nitrate and nitrite, were consumed due to the large growth of phytoplankton. However, during the rainy period, concentrations of ammonia, phosphate, silicate, nitrate, and nitrite, were very high towards the upper station due to the inflow of fresh water. Cyanobacteria Oscillatoria and Microcystis spp. were dominant in the Bunam Lake during the rainy period. Even in the Cheonsu Bay, cyanobacteria dominated due to the effect of discharge and diatoms, such as, Chaetoceros spp. and Eucampia zodiacus, which also proliferated significantly due to increased levels of nutrients. Since the eutrophication index was above 1 in Bunam Lake, it was classified as eutrophic water and the Cheonsu Bay was classified as eutrophic water only during the rainy season. In addition, a stagnant seawater-derived hypoxia water mass was observed at a depth of8m in the Bunam Lake adjacent to the tide embankment and the COD concentration reached 206 mg L^-1 in the bottom layer at B3. Based on this result, it is considered that the water quality will continue to deteriorate if organic matters settle due to continuous inflow of nutrients and growth of organisms while the bottom water mass is stagnant.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.4
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• pp.554-561
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• 2013

In this paper, we introduce a modeling and a process simulator developed with the aid of pRBFNNs for activated sludge process in the sewage treatment system. Activated sludge process(ASP) of sewage treatment system facilities is a process that handles biological treatment reaction and is a very complex system with non-linear characteristics. In this paper, we carry out modeling by using essential ASP factors such as water effluent quality, the manipulated value of various pumps, and water inflow quality, and so on. Intelligent algorithms used for constructing process simulator are developed by considering multi-output polynomial radial basis function Neural Networks(pRBFNNs) as well as Fuzzy C-Means clustering and Particle Swarm Optimization. Here, the apexes of the antecedent gaussian functions of fuzzy rules are decided by C-means clustering algorithm and the apexes of the consequent part of fuzzy rules are learned by using back-propagation based on gradient decent method. Also, the parameters related to the fuzzy model are optimized by means of particle swarm optimization. The coefficients of the consequent polynomial of fuzzy rules and performance index are considered by the Least Square Estimation and Mean Squared Error. The descriptions of developed process simulator architecture and ensuing operation method are handled.

• Journal of Environmental Impact Assessment
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• v.17 no.3
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• pp.189-200
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• 2008

As a transition zone between terrestrial and aquatic ecosystems, riparian areas of rivers and streams play significant roles in production and decomposition for river and stream systems. Understanding of the physical and ecological characteristics of riparian areas are, therefore, important for the management of river and stream systems. It is especially important to understand the characteristics of riparian areas for the Nakdong River in Korea which has a large watershed area and diverse land uses. This study aimed at collecting field data, according to stream types, which are essential for the management of riparian areas of the middle and lower reaches of the Nakdong River, Korea. Most riparian areas surveyed in this study had roads within 100 meters from river edges. Distances from water edge to banks were less than 1m for most riparian areas neighboring agricultural lands, indicating that those areas might be very vulnerable to pollutant inputs from non-point sources. Water quality data indicated that soil erosion in the riparian areas could be a major source of phosphorus input to the Nakdong River and land use patters might have a significant influence on nitrogen concentration in the river. Heavy metal concentrations in soils of the riparian areas of the river were below soil quality standards, except arsenic and chromium. Vegetation surveys showed that therophytes were the most frequently occurred riparian plants in the Nakdong River. Number of aquatic plant species increased downstream, with the most diverse aquatic plants observed in wetlands and irrigation canals of the West Nakdong River. Occurrence rate of naturalized plants and urbanization index were high in the survey sites adjacent to urban and agricultural areas.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.482-487
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of thawed beef loin. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -2$0^{\circ}C$ were higest by 3.4% to 30 days and by 1.8% to 60 days, respectively. And the thaw drip loss of -3$^{\circ}C$ freezing was more than -2$0^{\circ}C$ freezing. The cooking loss of water bath and pan boiling were increased significantly during freezing than the beginning of freezing, but were not different -3$^{\circ}C$ and -2$0^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -2$0^{\circ}C$ freezing was higher than -3$^{\circ}C$ freezing. The water soluble protein extractability of -3$^{\circ}C$ freezing was not significant different during freezing storage, that freezed at -2$0^{\circ}C$ was increased during freezing. The "L" value of the beginning of freezing was higher than during freezing, the "a" value was not different during freezing, and the "b" value during freezing was higher than the beginning of freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ and -2$0^{\circ}C$ freezing were highest by 94.4% to 45 days and by 94.0% to 15 days, respectively. The shear force value during freezing was higher than the beginning of freezing, the myofibrillar fragmentation index was not significant different during freezing. The pH was increased to freezing 30 days, after that was decreased.ays, after that was decreased.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.111-115
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• 1990

The rheological properties of soybean paste suspensions as affected by concentrations and heating were studied. All suspensions of soybean paste showed thioxotropic plastic behavior. The concentrated suspensions below the ratio of water to soybean paste, 1.25 exhibited Figure-eight phenomena which were presented by two Intersections of the up curve with the dorm curve of shear rate. The dilute suspension (soybean paste: water=1:2) showed H type hysteresis loop at low temperature. But increasing the heating temperature above $60^{\circ}C$, the hysteresis loop exhibited a Figure eight phenomenon. Consistency index of the suspensions increased remarkably by heating and showed the highest value around isoelectric point of the protein. It was suggested that the proteinous nitrogen might be the main component taking part in viscous behavior under different pH and heat treatment.

• Journal of the Economic Geographical Society of Korea
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• v.7 no.2
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• pp.157-170
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• 2004

The Boundary Region in Gyeonggi Province has environmental vulnerability due to the increasing development pressure although usually regarded as an ecologically well-preserved region. This paper is aimed to analyze the status of environmental loading on natural resources of the Boundary Region in Gyeonggi Province through investigating land-use conversion pattern during the past 15 years(1985-2000), the attitude of the local community towards conservation policy, and the status of environmental treatment facilities for water quality management. The results are as follows. Firstly, the development pressure has been focused upon the southwestern part of the Boundary Region in Gyeonggi Province such as Gimpo, Paju, Dongduocheon, and Yangju since 1995. Secondly, local residents' strong aversion exists towards the conservation policy led by the government because of their underdevelopment. Finally, the risk of environmental degradation is high because the region is not equipped with adequate environmental treatment facilities for water quality management. The status of environmental loading in the Boundary Region suggests the necessity to establish a well-designed management plan for natural resources in this area.

• Journal of Environmental Science International
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• v.19 no.6
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• pp.665-670
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• 2010

Pollutants from urban pavement consists various kinds of substances which are originated from dry deposition, a grind out tire, corrosive action of rain to pavement and facilities and raw materials of the road etc.. These are major pollutants of urban NPS (Non-point source) during rainfall period. However there is not enough information to control such pollutants for appropriate management of natural water quality. In this study of transportation areas, three monitoring stations were set up at trunk road, urban highway and national road in Gyeongnam province. Runoff flow rate was measured at every 15minutes by automatic flow meters installed at the end of storm sewer pipe within the road catchment area for water quality analysis. Data was collected every 15 minutes for initial two hours of rainfall. Additional samples were collected 1-4 hours interval till the end of rainfall. The monitoring parameters were $COD_{Mn}$, SS, T-N & T-P and heavy metals. The average EMCs of TSS and $COD_{Mn}$ were 62.0 mg/L and 24.2 mg/L on the city trunk road, which were higher than those of urban highway and national road, indicating higher pollutant loads due to activities in the city downtown area beside the vehicle. On the other hand, the average EMC of T-N and T-P were in the range of 2.67-3.23 mg/L and 0.19-3.21 mg/L for all the sampling sites. Heavy metals from the roads were mainly Fe, Zn, Cu and Mn, showing variable EMCs by the type of road. From the TSS wash-off analysis in terms of FF(first flush) index, first flush phenomenon was clearly observed in the trunk road(FF : 0.89-1.43). However, such mass delivery behavior was not apparently shown in urban highway(FF : 0.90-1.11) and national road(FF : 0.81-1.41).

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.211-217
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• 2000

To standardize quality characteristics of commercial doenjang prepared by traditional method, general components, organic acids, amino acids and fatty acid composition were investigated. Moisture, crude protein, crude lipid, titratable acidity (expressed as milliliter of 0.1 N NaOH), acid value and salinity were 54.7%, 13.8%, 8.0%, 14.4mL, 45.7mg/g and 11.8%, respectively. The content of amino type nitrogen was 345.3mg% (w/w) in the range of 207.6 to 443.5mg% being 1.1~2.2-fold for all samples. Average value of Hunter color for L(lightness), a(redness) and b(yellowness) were 37.4, ＋9.7 and ＋21.3, respectively. Browning index value(expressed as optical density at 425 nm) of water-soluble compound(2.58) was above 7.1 times higher than that of the water-insoluble compound(0.38). Total contents of free and total amino acid were 3.81 and 9.72%, respectively, and then the former(1.1~3.7 times) was more different in all samples tested than that of the latter(1.1~2.0 times). Among amino acids, glutamic acid was abundant and its content of free and total amino acids was 0.57 and 1.24%, respectively. Of organic acids, lactic acid was the most abundant being 0.34%(average) and ranged from 0.15 to 0.86%. Linoleic acid(52.17%, as area%) was the highest content of the total fatty acids. Unsaturated and polyunsaturated fatty acids were 83.89 and 61.189%, respectively. Polyunsaturated fatty acid was markedly different among all samples and ranged from 51.52 to 64.91%.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.250-257
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• 2021

Laundry industry has traditionally been considered an industry that generates large amounts of wastewater and Volatile Organic Compounds(VOCs). This is still the case until now. Household laundry detergents are produced and distributed within the safety regulations on the amount of harmful substances detected. While industrial laundry detergents are often distributed without safety regulations, and even laundry workers manufacture and use them on their own. This contaminates water and air and also threatens the safety of workers. This study is a basic study for distributing eco-friendly detergents(EFD-A) developed through previous studies to the laundry industry. Safety, washability and wastewater quality of EFD-A are evaluated. Three existing commercial detergents(PD1, PD2, LD4) are also evaluated to compare with EFD-A. The safety of detergents is confirmed by the content of optical brightener, VOCs, and arsenic. Washability is evaluated by the difference in reflectance of washed and unwashed artificial soiled fabrics according to detergent concentration, washing temperature, and washing time. TOC is used as the index of assessing the wastewater quality. The results are as follows; EFD-A doesn't contain the optical brighteners, VOCs, and arsenic. The optimal washing conditions for EFD-A are 3 g/L concentration, 40 ℃ washing temperature, and 30 min washing time. The soil removal efficiency is about 71 %, which was similar to or somewhat superior to that of PD1, PD2, and LD4. TOC is 63.5 %, which is about 15 % lower than the discharge limit. Through this study, the developed detergent EFD-A can be used as a safe and eco-friendly detergent for the human body and the environment.