• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.4
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• pp.204-212
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• 2005

Recognition has emerged that nutrient inputs from the submarine discharge of fresh, brackish, and marine groundwaters into the coastal ocean are comparable to the inputs via river discharge. The coastal areas of the Korea peninsula and adjacent seas exhibit particular importance in the role of submarine groundwater discharge (SGD), in terms of the magnitude of SGD and associated continental material fluxes. For example, in the southern sea of Korea, SGD transports excess nutrients into the coastal regions and thus appears to influence ecosystem changes such as the outbreak of red tides. Around volcanic island, Jeju, which is composed of high permeability rocks, the amount of SGD is higher by orders of magnitude relative to the eastern coast of North America where extensive SGD studies have been conducted. In particular, nutrient discharge through SGD exerts a significant control on coastal ecosystem changes and results in benthic eutrophication in semi-enclosed Bang-du bay, Jeju. In the entire area of the Yellow Sea, tile submarine discharge of brackish groundwater and associated nutrients are found to rival the river discharges into the Yellow Sea, including those through Yangtze River, Han River, etc. In the eastern coast of the Korea peninsula, SGD is significantly higher during summer than winter due to high hydraulic gradients and due to wide distribution of high permeability sandy zones, faults, and fractures. On the other hand, in the estuarine water, downstream construction of the dam in the Nakdong River, SGD was highest when the river discharge was lowest (but water level of the dam was highest). This suggests that even though there is no visible freshwater discharge into this estuary, the discharge of chemical species is significant through SGD. On the basis of the results obtained from the coastal areas of the Korea peninsula, SGD is considered to be an important pathway of continental contaminants influencing tidal-flat ecosystems, red tides, and coral ecology. Thus, future costal management should pay great attention to the impact of SGD on coastal pollution and eutrophication.

• Environmental and Resource Economics Review
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• v.18 no.2
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• pp.279-309
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• 2009

Greenhouse gas emissions should be precisely forecast to reduce the emissions from industrial production processes. This study calculated the direct and indirect $CO_2$ emission intensities of 401 industries using the Input-Output tables 2003 and statistical data on the amount of energy use. This study had some limitations in drawing study findings because overseas data were used given the lack of domestic data. Other limiting factors included the oil distribution problems in the oil refinery sector, re-review of carbon neutral, and insufficient consideration of waste treatment. Nonetheless, this study is very meaningful since the direct and indirect $CO_2$ emission intensities of 401 industries were calculated. Specifically, this study considered from the zero-waste perspective the effects of waste, which attract interest worldwide since coke gas and gas from the steel industry are obtained as byproducts for the first time in Korea. According to the results of the analysis of $CO_2$ emission intensity per industry, typical industries whose indirect $CO_2$ emission intensity is high include crude steel making, Remicon, steel wire rods & track rail, cast iron, and iron reinforcing rods & bar steel. These industries produce products using the raw materials produced in the industrial sector whose $CO_2$ emission intensity is high. The representative industries whose direct $CO_2$ emission intensity is high include cement, pig iron, lime & plaster products, andcoal-based compounds. These industries extract raw ore from nature and refine them into raw materials that are useful in other industries. The findings in this study can be effectively used for the following case: estimation of target $CO_2$ emission reduction level reflecting each industrial sector's characteristics, calculation of potential emission reduction of each policy to reduce $CO_2$ emissions, identification of a firm's $CO_2$ emission level, and setting of the target level of emission reduction. Moreover, the findings in this study can be utilized widely in fields such as System of integrated Environmental and Economic Accounting(SEEA) and Material Flow Analysis(MFA) as the current topic of research in Korea.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.144-154
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• 2008

The purpose of this study was to describe quantitatively trophic structures and to analyze energy flows in the Lake Namyang using the Ecopath with ecosim (Walter et al., 1997). The sampling and analyses were carried out at 6 sampling sites of the Lake Namyang during May and November in 2007. A total of 10 groups were considered in this study (detritus, macrophytes, phytoplankton, zooplankton, zoobenthos, Cyprinus carpio, Carassius cuvieri, Carassius auratus, Pseudobagrus fulvidraco and other fishes) to assess the trophic relationship, energy flows and interactions between them. As a result, it was concluded that Lake Namyang was consisted of primary producers (Detritus, Macrophytes, Phytoplankton), primary consumers (Zooplankton, Zoobenthos, Cyprinus carpio, Carassius cuvieri, Carassius auratus, Other fishes) and secondary consumer (Pseudobagrus fulvidraco). The total system throughput was estimated at $14.1\;kg\;m^{-1}\;year^{-1}$ including a consumption of 39%, exports of 21%, respiratory flows of 12% and flows into detritus of 28%. MTI analyses indicate that Pseudobagrus fulvidraco have positive impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. On the other hand, other fishes have negative impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. All the functional groups except detritus had a negative impact on themselves and this may show within-group competition for the same resources.

• Journal of the Mineralogical Society of Korea
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• v.26 no.2
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• pp.101-110
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• 2013

Due to the large specific surface area and great reactivity toward environmental contaminants, nanocrystalline mackinawite (FeS) has been widely applied for the remediation of contaminated groundwater and soil. Furthermore, nanocrystalline FeS is rather thermodynamically stable against anoxic corrosion, and its reactivity can be regenerated continuously by the activity of sulfate-reducing bacteria. However, nanocrystalline mackinawite is prone to either spread out along the groundwater flow or cause pore clogging in aquifers by particle aggregation. Accordingly, this mineral should be modified for the application of permeable reactive barriers (PRBs). In this study, coating methods were investigated by which mackinawite nanoparticles were deposited on the surface of alumina or activated alumina. The amount of FeS coating was found to significantly vary with pH, with the highest amount occurring at pH ~6.9 for both minerals. At this pH, the surfaces of mackinawite and alumina (or activated alumina) were oppositely charged, with the resultant electrostatic attraction making the coating highly effective. At this pH, the coating amounts by alumina and activated alumina were 0.038 and 0.114 $mmol{\cdot}FeS/g$, respectively. Under anoxic conditions, arsenite sorption experiments were conducted with uncoated alumina, uncoated activated alumina, and both minerals coated with FeS at the optimal pH for comparison of their reactivity. Uncoated activated alumina showed the higher arsenite removal compared to uncoated alumina. Notably, the arsenite sorption capacity of activated alumina was little changed by the coating with FeS. This might be attributed to the abundance of highly reactive hydroxyl functional groups (${\equiv}$AlOH) on the surface of activated alumina, making the arsenite sorption by the coated FeS unnoticeable. In contrast, the arsenite sorption capacity of alumina was found to increase substantially by the FeS coating. This was due to the consumption of the surface hydroxyl functional groups on the alumina surface and the subsequent occurrence of As(III) sorption by the coated FeS. Alumina, on the surface area basis, has about 8 times higher FeS coating amount and higher As(III) sorption capacity than silica. This study indicates that alumina is a better candidate than silica for the coating of nanocrystalline mackinawite.

• Journal of Applied Biological Chemistry
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• v.59 no.4
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• pp.273-280
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• 2016

We investigated the contents of total phenols, anthocyanins, carotenoids and the antioxidant capacity of black carrot, black currant, acaiberry, black raspberry, and blueberry. We also examined the physical and organoleptic characteristics of pudding with added black carrot extract following 7 days of storage. Black carrot and black raspberry had the highest total phenols. Blueberry contained the highest anthocyanins and black currant equaled black carrot in carotenoids. Anti-oxidant capacity measured by 1,1-diphenyl-1,2-picrylhydrazyl and 2,2-azino-bis-3-ethyl-benthiazolin-6-sulfonic acid was highest in black raspberry and black currant followed closely by black carrot. In pudding, redness was increased and blueness decreased by adding black carrot extract, but the trend was partially reversed during 7-day storage due to oxidation of the anthocyanins, which are stable in acid situation. As black carrot extract contents were increased, pH value decreased. The pudding's hardness, adhesiveness, springiness, cohesiveness, gumminess and chewiness were optimal with 7.5 % black carrot extract. In conclusion, black carrot is moderately rich in anthocyanins and phenolic compounds. In pudding adding 7.5 % black carrot extract was optimal for organoleptic qualities. However, additional studies are needed to develop methods for protecting anthocyanins from breaking-down during storage of back carrot pudding.

• Korean Business Review
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• v.13
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• pp.133-157
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• 2000

This paper investigate to construct a new strategic trading model which contains the broker and overconfident informed trader. Assuming more favorable situation for the broker, this paper construct a two period model. At period I overconfident informed trader and liquidity traders participate to trade. At this time the broker does not execute transaction of his own account. he only transfer customer's order by commission. At period 2, the broker identifies informed trade of previous period and he execute the trade of his own account with liquidity traders. The effects of overconfidence to the expected transaction volume and expected transaction profit, and price variability are summarized as follows: (i) As the degree of overconfidence increases, the expected transaction volume of informed trader increases. Under the restriction of moderate degree of overconfidence, it also increases the expected transaction volume of broker. In sum, overconfidence behavior of informed trader increases the expected transaction volume. (ii) As the degree of overconfidence increases, the both expected profit of informed trader and broker decrease. (iii) As the degree of overconfidence increases, unconditional variances of price for each periods increase. And as the degree of overconfidence increases, the informativeness of prices for each period increase. Finally, some limitations of this paper and direction for further research were suggested.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.117-131
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• 2021

Urban development is continuously being carried out to stabilize housing supply. The importance of ecosystem services assessments considering the various urban spatial structures is emerging as land use change in the wake of urban development has impact on the provision of ecosystem services. However, few studies are available as to the effects of land use transition in agricultural land due to urban development on ecosystem services. The purpose of this study is to examine the applicability of decision-making in the urban planning process by analyzing the impact of land use change on ecosystem services due to urban development. Therefore, the scenario was set on before and after the city development, targeting Namyangju Wangsuk Zone 1 and InVEST model was used to compare and analyze changes in value of ecosystem services. Analysis results of ecosystem services before the urban development, it turned out that habitat quality and water yield increased overtime but carbon storage and crop production decreased. Analysis results of ecosystem services after the urban development indicated that all items in ecosystem services by scenario decreased more than in 2018. Among the scenarios of urban development, compact city had the lowest value of water resource supply but had the highest value in terms of habitat quality, carbon storage amount, and crop production. The study results demonstrate that the compact city has positive effects on ecosystem services and is expected to be used as the basic data for supporting policy decision-making in the establishment of future urban development and management plans.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1018-1027
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• 2005

The purpose of this study was to investigate nutrients intake and health-related behaviors in elderly people residing in Gyeongsan-si, Gyeongbuk who have no problem in daily living. Information on general characteristics of the elderly, health-related behaviors and dietary habits were obtained by interview based on questionnare. Dietary nutrients intake data were obtained through the 24 recall method. The subject group of this study was composed of 113 males and 112 females, the average age being $73.1\pm6.06$ years old. In health related factors, $76.9\%$ of subjects exercised regularly. The rates of alcohol drinking and smoking showed to be $38.2\%\;and\;22.2\%$, respectively. There were many elderly with neuralgia, hypertension, and gastrointestinal disease, especially female were worse. Average heights of the subjects were lower than the standard established in the Korean Recommended Dietary Allowances, and average weights were similar to the standards. The mean BMI and WHR were 24.8 (male 23.7, female 25.7) and 0.92 (male 0.92, female 0.89), respectively. Most of the subjects had a regular meal pattern comsuming three meals a day, and many elderly, especially more than $79.5\%$ of female, prepared the meals for themselves. Mean daily energy intakes and RDA percentage of energy intakes of the male and female subjects were estimated as 1426.9kcal $(79.3\%)$ and 1381.3 kcal $(86.3\%)$, respectively. Mean daily intakes of nutrients were estimatied as 48.1g for protein, 411.3mg for calcium, 8.05mg for iron, 541.8 R.E. for vitamin A, 0.84mg for vitamin $B_1$, and 0.79mg for vitamin $B_2$. Most nutrients except protein, clacium, iron and vitamin $B_2$ were consumed over $75\%$ of the RDA. Female elderly showed significant lower intakes (p<0.05) for most of the nutrients except calcium, phosphorus and vitamin ethan the elderly male.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.1-7
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• 2017

This study was conducted to investigate the microbial loads in mulberry fruits depending on cultivation environment and fruit ripeness. The population levels of total aerobic bacteria in mulberry fruits collected from open field orchards were higher than those from three plots protected within plastic green houses. In regards to fruit ripeness, the levels of total aerobic bacteria in ripe black fruits were higher than those in unripe green and red mulberry. From the farms into where livestock animals were allowed to enter, Escherichia coli was detected in soil at a level of 4.26~4.94 log CFU/g and in mulberry fruits at 5.03~6.07 log CFU/g, while no coliform and E. coli were detected from where the intrusion of livestock was prevented. We also examined the density change of inoculated E. coli in mulberry fruits as they were becoming mature. While E. coli did not increase in green fruits, two and four log CFU/g increases at $20^{\circ}C$ and $37^{\circ}C$, respectively, were observed with red and fully mature black mulberries during 48 hours incubation. To ensure the food safety of mulberry, it is suggested that the introduction of E. coli into a farm through livestock should be prevented and more hygienic caution should be taken especially when the fruits are ripe.