• Korean Journal of Ecology and Environment
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• v.47 no.3
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• pp.219-224
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• 2014

This study was conduct to the reduction and elimination of Limnoperna fortunei that problem in the facilities and water supply pipeline is done to review proposals for the controls. In order to effectively removal the larva and the adult of that, chlorination and being used to an existing method is to be commended. The water temperature of Limnoperna fortunei spawning season was ranged 16 to $17^{\circ}C$ during May to early November. A chlorination of this period is appropriate in order to control a larva. However, existing in the attached young and old shell at the same time consistently been deemed to apply, because it must be taken into account. The range of concentration of chlorination to control the biomass for Limnoperna fortunei was from 0.5 to 1.0 ppm. Proliferation attached to the mitigation or appropriate technology to solve the domestic situation the priorities of the choice of a more urgent. Also, the monitoring of water temperature and larva will constantly to be done. And development of larva monitoring method as well as after chlorine treatment is effective analysis needed. Finally, we are expecting to good use in validating the results presented in this study.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.651-658
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• 2008

Estuary barrier is a hydraulic structure constructed to supply safely water as protecting chlorine penetration of sea water. However, the barrier brings about a problem which decreases original functions of estuary because hydraulic ecology was disrupted as obstructing natural water exchange between fresh water and sea water. It is important to supply Enough fresh water in the estuary ecosystem. But it is possible to reduce the problems brought from barrier throughout efficient water gate operation of estuary barrier. It was shown in this study that the environmental effect of estuary in Nakdong river was investigated according to the control of water level. Also, the basic information about the effective water gate operation was provided. The analysis results showed that the release rate of estuary was increased about 20% as changing the operational water levels. This helps supplying fresh water durably to the mixing zone. Also, CE-QUAL-W2 model was utilized to assess water quality. The values of BOD and COD were not changed in estuary area. From the result, it was analyzed the effect of water quality according to the water gate operation was not indicated.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.5
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• pp.446-475
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• 2000

Performance of a water-to-water multi-type heat pump system using R22 has been experimentally investigated. Total refrigerant flow rate was adjusted with a variable speed compressor and the refrigerant flow rate for two indoor units were controlled by electronic expansion valves. Evaporator outlet pressure of refrigerant and indoor unit outlet temperatures of secondary fluid were selected as controlled variables. Experiments were carried out for both cooling and heating modes using PID control method. Results show that the multi-type heat pump system can be adequately controlled by keeping control gains at certain levels for various operating conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.59-64
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• 1991

Studies comparing the relative effects of water soluble extract of Ganoderma lucidum kale juice and sodium dextrothyroxine on lipid component in liver brain and testis of hypercholeste-rolemic rats for 4 weeks. Therefore the aim of this work was to investigate for prevention in cardiovascular disease, Total cholesterol concentration in liver were significantly lower kale juice and sodium dextrothyroxine(1.25mg/kg diet) fed groups than the other groups and trigly-ceride concentration was significantly lower Ganodrma lucidum fed group than in control group;. Total cholesterol concentration in testis were lower other groups than in control group and triglyceride concentration were significantly lower cholesterol Ganoderma lucidum and kale juice groups in control group. Phospholipid concentration in testis was higher sodium dextroth-yroxine fed group thanin control group.

• Journal of the Korean Society of Visualization
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• v.12 no.1
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• pp.30-34
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• 2014

Bluff bodies under the external periodic force vibrate at their own natural or forced frequency. Rectangular bodies or similar structures such as high-rise towers and apartments, and recently a well-cited application - offshore floating bodies, usually needs to reduce these vibrations for stability and the mode control. Therefore, this study is aiming to reduce or control the vibration of a structure by a passive control method, i.e., TLCD (Tuned Liquid Column Damper). Controlling a moving body with a TLCD based on a variety of the orifice shape has been preliminary studied. In order to get a proper control, an optimized study is made on the design of the orifice shape, which has internal plates with the holes. The results show the force acting on the body due to the periodic movement highly depends on the number of holes on the plate and the height of the water level. Therefore, the optimum shape of the orifice and the height of the water level should be confirmed by a series of experiments.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.915-925
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• 2012

On-off control performance of target pumping station was experimented by changing measurement methods for storage level or inflow and operating logic for control system setting. Four scenarios with different measurement methods and operational logic were examined in the Matlab/Simulink environment. Controller's on-off control repetition that was frequent before has been reduced and more effective and stable system operation was found to be possible with the scenarios. Moreover, defensive operation enforced prevention of floods by changing measurement methods enabled economic operation that made an utmost use of storage volumes.

• Journal of Biosystems Engineering
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• v.11 no.1
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• pp.31-36
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• 1986

As a part of study on automatic control system for green houses, an automatic irrigation system was developed by using microcomputer. For the study, gypsum block was used as a sensing device of soil moisture and its data was designed to transfer to microcomputer through A/D converter. Also, software which be able to control the irrigation time and flow rate by the solenoid valve was developed. This system was tested by using practical data and the following results were summarized. 1. Since the gypsum was very accurate in addition with chiep and easy to manufacture, it turned out to be a very good device to detect the soil moisture in this system. 2. Also, solenoid valve was very excellent device for controlling the water flow rate since its control error is less then 1% when the irrigation time is over 100 seconds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1298-1303
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• 1999

For the purpose of improving the qualities of immatured soybean(Seoklyang), the effects of table height (0, 5, 10, 15mm) and time(60, 66, 72, 78 sec) for microwave blanching on physicochemical properties were investigated. Enzyme inactivities lipoxygenase and peroxidase for all there conditions were more de creased than for control and water blanching. Enzyme activity of each conditions was expressed as percentage on the enzyme activity of control. Lipoxygeanse activity and peroxidase activity of immatured soybeans were about 20% and 10% levels, respectively. Also the color showed the higher L(lightness), b(yellowness), chroma(brightness) values, but the lower a(redness) and hue angle. Vitamin C content was worse than for control, but was better than for water blanching. Hardness with a few exceptions showed the higher value for control.

• Proceedings of the Safety Management and Science Conference
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• 2003.11a
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• pp.185-198
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• 2003

This study is to develop and operate the R-FCE(Real-time Fuzzy Control Expert System) model on the SBR(Sequency Batch Reactors) type sewage disposal facility which is for the environmental problem of future and the effective treatment. It is the system that regularly handles the input, output information in real time by the Fuzzy control IF-THEN rule. Nowadays the water pollution caused by the increase of population and the industrialization already exceeds the purifying ability of nature and is getting worse. The sewage disposal facility needs an expert having wide experience and know-how because the quality or quantity of inflow water is so irregular that the process of sewage disposal is difficult. In the nation, however, the accumulation of technology is so weak because field-operators avoid the long-term duty. So the accurate and speedy decision or control of field are difficult in the case of emergency situation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1072-1078
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• 2001

The real time optimal control algorithm of the DDC controller for chilled water and supply air temperature set-point of heating, ventilating, air-conditioning and refrigeration systems has been researched for minimization of the total power which is consumed by the chiller, chilled water pump and air handing unit fan. The study has been done by using TRNSYS program in order to analyze the central cooling system in terms of the environmental variables such as indoor cooling lead and wet-bulb temperature. This optimal control alogorithm saves more energy and is suitable for real time on-line control in comparison with conventional method.