• Journal of Wetlands Research
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• v.20 no.4
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• pp.304-313
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• 2018

Agricultural land reclamation in Saemangeum tidal land project is mostly planned to be completed by 2020. Irrigation water for the land is required to be prepared by that time. However, water quality for the irrigation sources is barely meet the target concentration. This paper described the reduction effect of and policy consideration for best management practices (BMPs) which were fertilizer prescription by soil test (SO#1), mixed application of SO#1 and 3 (SO#2), drainage gate control (SO#3), time-release fertilizer application (SO#4), and control (CT). Reduction of paddy runoff was relatively higher in SO#3 (25%) and SO#1 (27%) while lower in SO#4 (9%) and SO#2 (7%) than that in CT. In addition, farmers promised to follow the BMP guidelines but they didn't because of the several problems caused for the BMPs implementation. Thus, it recommended developing an automated control of irrigation gate and paddy water depth and supporing farmers for NPS pollution control and irrigation water reduction.

• Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.1-4
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• 2002

The modulatory effects of oxytetracycline treatments at high concentrations on the infection potential of scuticociliates in cultured juvenile olive flounder (Paralichthys olivaceus) and density of the ciliates in culturing water were investigated. The groups bathed with 400 and 500 ppm of oxytetracycline showed significantly lower intensities of scuticociliates on the fish and considerably lower number of the ciliates in culturing water when compared with the control group. However, the intensity of scuticociliates on the fish in the group bathed with 300 ppm of oxytetracycline was not significantly different with that of the control group in spite of considerably lower number of scuticociliates in culturing water than in that of the control group. Although the intensities of scuticociliates on the fish intubated orally with 400 and 500 mg/kg of oxytetracycline were lower than that of the control group, there were no statistical significances. In contrast, the fish fed 300 mg/kg of oxytetracycline showed significantly lower intensity of scuticociliates when compared with other groups. The results of this study suggest that oxytetracycline treatments can modulate occurrence of scuticociliatosis in fish farms probably through change of bacterial density, damaging to scuticociliatosis and immuno-suppression of fish.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.344-350
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• 1998

Lipid lowering properties from three plant water extracts, Rosa rugosa, Crataegus pinnatifida and Polygonum cuspidatum, were tested by supplementing a 1% high-cholesterol diet with them in rats. Plasma triglyceride levels in Rosa fugosa, Crataegus pinnatifida and Polygonum cuspidatum groups were significantly lower compared to that of the control. by 29% , 24% and 47% respectively. hepatic trigylceride levels in Rosa rugosa and Crataegus pinnatifida groups were significantly lower compared to the control by 11% and 15% respectively. Hepatic HMG-CoA reductase activity in Rosa rugosa group was significantly greater compared to the control by 406%. Hepatic ACAT activity was significantly lower in Polygonum cuspidatum group compared to the control by 28%. by multiple regression results, only plasma cholesterol was associated significantly (p<0.05) with liver HMG-CoA reductase activity. Plasma cholesterol explained 12% of thevariance of the liver HMG-CoA redctase activity. In conclusion, we have showen that hot water extracts from Rosa rugosa, Crataegus pinnatifida and Polygonum cuspidatum lowered plasma triglycerides in rats fed on a high-cholesterol diet. Data suggests that these extracts could potentially prevent or treat hypertriglyceridemia induced by a high fat diet and fatty liver.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.362-366
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• 2016

In this study, humidity control ceramics with good adsorption/desorption capabilities and high strength were fabricated from drinking-water treatment sludge (DWTS) and Onggi soil. The DWTS powder heat-treated at $800^{\circ}C$ and Onggi soil were mixed at weight ratios of 40:60, 50:50, 60:40, and 70:30 and fired at $800-1000^{\circ}C$. With increasing DWTS content, density and flexural strength increased. For the sample with a DWTS:Onggi soil weight ratio of 70:30, porosity and specific surface area decreased with increasing firing temperature, attributed to densification and grain growth at high firing temperatures. From the results obtained, a firing temperature of $800^{\circ}C$ is the optimum condition for fabricating humidity control ceramics with good adsorption/desorption capabilities and strength. The maximum adsorbed amount for the sample fired at $800^{\circ}C$ was $439g/m^2$.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.5
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• pp.453-459
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• 2009

The DSME guide plate(GP) has been developed with the target to improve the cavitation and vibration performance when used with discharging cooling water around the outlet of LNG carrier. It was proven that it could as well be applied as a powerful wake control device on its own, even without discharging cooling water. However, it has to be taken into account that it inevitably results in speed loss. This study shows the possibility to design a GP which simultaneously improves both vibration and speed performance. The study intends to outline how to design the preliminary GP configurations from both the vibration and the speed performance points of view. Further, the study offers design guidance for the hull form and the propeller when adapting GP as a wake control device.

• Journal of Oriental Neuropsychiatry
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• v.10 no.2
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• pp.115-126
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• 1999

This study was conducted to find out the effects of Woohwangchungsimwon on learning and memory in the NOS inhibitor treated rats. The Morris water maze was used in evaluating them. The result of the study was summarized as follows. 1. In the learning test, three groups have showed a gradual improvement of learning ability by repeating the trials in Morris water maze. WHCS group have showed statistical improvement than control group at 4,5,6 trial(p<0.05, p<0.01, p<0.01). 2. In the memory test, the first latency of WHCH group was statistically shortened than that of control group(p<0.05). 3. In the memory test, there was no statistical difference in the entry number between WHCH group and control. 4. In the memory test, there was no statistical difference in the memory score between WHCH group and control. The result of this experimental study presents that Woohwangchungsimwon has the improving effect on impaired learning and memory in NOS inhibitor treated rats, and implies that Woohwangchungsimwon may be one of the useful prescription for the treatment of vascular dementia after cerebral ischemia.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.743-749
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• 2010

The primary object of this study was to develop the control algorithm and program for automatic submersible buoy which is free to move vertically within the water column by adjusting weight and buoyancy forces by air control. The experiment was performed to validate the usefulness of the program in the indoor water tank. In the experiment, the automatic submerging and surfacing of the buoy were controlled by water-pressure gauge and air control system. The buoy is raised by injecting compressed air from a compressor and then is lowered by releasing the air. The submerging and surfacing characteristics of the buoy calculated with the numerical model were similar to measurements obtained with the experiment. It was concluded that the algorithm and program could be useful in analyzing various parameters and submerging mechanisms required to design new type of automatic submersible fish cage system.

• The Korean Journal of Physiology
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• v.14 no.1
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• pp.15-23
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• 1980

In an attempt to clarify the influence of lung volume and water temperature on the heart rate response during apneic face immersion in the trained athletes, 10 soccer players were studied while holding their breath as long as possible after full inspiration(TLC), full expiration(RV) or normal breath(FRC) with face immersion in water. The electrocardiogram(Lead II) was recorded before and during each manuever and compared with 20 control subjects. The results are summarized as follows; 1) Resting heart rate was significantly lower in the athletes than that of the control groups. 2) During apneic face immersion, severe bradycardia were observed in both groups and the heart rate was significantly lower in the athletes than that of the control groups. 3) The degree of the bradycardia (maximum percent reduction of heart rate, HRmax.) were inversely propotional to the lung volume and water temperature. In the above results, bradycardial response was more sensitive in the athletes than the control. It was suggested that diving bradycardia was related to the gas content in the lung and reflex from the cold receptor in the face.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.5
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• pp.717-722
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• 2013

The wastewater reclamation and reusing system has been rising as an alternative of water resource exhaustion that the whole world is experiencing. In order to be able to bring about improvement of the existing wastewater reclamation and reusing system, this research has developed of Conversion-Human Machine Interaction (C-HMI) based real-time control and monitoring system such as a sensor module and gate module, web monitoring system. This system was communication almost-error-free in various environment and situation. As a result, we have achieved our goal that has to doing work correctly as a sensor and gateway module that communication error is less than 0.2% throughout the embodied system and add that it can be easily controled and configured as an interface equipment to a complex sensor of water quality. According to this, the construction of a database capable of analyzing and assessing collection, storage and various elements of reliable water quality and flow rate data can be possible.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.4
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• pp.93-103
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• 2012

A suction-saturation control technique based on flow pump system was developed to investigate hydraulic properties in unsaturated soils. The flow pump system is designed based on the principle of the axis-translation technique and triaxial equipment, and gives the suction-time and suction-saturation curves, the primary relationship needed for interpreting the response of unsaturated soils and link between theory and the material properties in unsaturated soil mechanics. Using the suction-saturation control technique, suction-time relationship and soil-water retention curve (SWRC) during hydraulic hysteresis were investigated with different net confining pressures and porosities. Three types of soils-two sands and a silt were used in this paper. This paper showed the effect of the hysteresis on the SWRC due to different net confining pressures and porosities. This means that a careful decision must be made as to which condition is to be modeled, since the delicate difference of the conditions in physical modeling can cause the different experimental output.