• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.95-96
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• 2010

This paper proposes photovoltaic thermal hybrid module to get the electrical and Thermal performance of building integrated photovoltaic(BIPV) system. BIPV system is decreased the system efficiency because output of PV is decreased by the thermal rising on generating. In order to improve the efficiency of BIPV module, water cooling system is applied and generated thermal is used the warm water system. Water cooling system uses the flux control algorithm considering water temperature and power loss. Electrical and thermal performance of proposed photovoltaic thermal hybrid module is confirmed through the actual experiment and herby proved the valid of this paper.

• Journal of Korean Society for Geospatial Information Science
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• v.16 no.3
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• pp.65-69
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• 2008

This study is aimed to develope a remote control ship for acquisition of various underwater information. Remote control ship equipped with GPS, echosounder, sidescan sonar, subbottom profiler. Remote control ship is an automatic system for acquisition of inland water and coast information. For the development of remote control ship, underwater information acquisition of reservoir, dam, polluted area is expected. Also, multibeam echosounder, image sensor, water analysis sensor, etc. could be equipped in one ship. So robot-ship will be applied for the most part of industry managing water resources and preventing the flood by making bed topographic map and estimating water volumes.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2064-2069
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• 2008

The Resonance Control Cooling System (RCCS) prototype installed in KAERI site has been designed to control the resonant frequency of the normal conducting drift tube linac (DTL) for the Proton Engineering Frontier Project (PEFP). The RCCS water pumping skid is composed of two channels as a by-passing the cooling water and a plate heat exchanger. The required temperature can be achieved by mixing both channels in order to control its the resonant frequency at 350 MHz. The temperature controlled water pumping skid operates in combination with the Low Level Radio Frequency (LLRF) system. We have discussed the design, modeling with each components, control scheme, fabrication and test results of the water pumping skid for resonant frequency control of the DTL cavity. In conclusion, the fabricated RCCS prototype through the optimization of modeling has corresponded with the design requirement and concept.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.2
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• pp.200-207
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• 2017

The purpose in having a control surface on ships is to control the motion of the ship. The control surface may be composed entirely of a single movable surface or of a combination of fixed and movable portions. A control surface has one sole function to perform in meeting its purpose, and that is to develop a control force in consequence of its orientation and movement relative to the water. The forces and moments generated as a result of this rotation and angle of attack then determine the manoeuvring characteristics of the ship. In this paper, two-dimensional flow characteristics of a flapped rudder and a water-blowing control rudder were accomplished respectively by PIV method in a circulating water channel. Model test has been carried out with different angles of attack of main foil (NACA 0012) and flap's deflection angles to predict the performance of the flapped rudder and the water-blowing control rudder. The 2-frame particle tracking method has been used to obtain the velocity distribution in the flow field. $Re{\fallingdotseq}3.0{\times}10^4$ has been used during the whole experiments and measured results have been compared with each other.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.269-274
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• 2013

We are used with the alkaline ion water which an application field does to object for drinking water compare with the alkaline ion water which asked ion acid electrolysis so as to be very different. This is used with sterilization disinfection use by residual chlorine in case of strong acidity according to ph intensity, and in case of middle acidity use by washing and face washing, and mix with meal materials in case of weak acidity widely usable in cooking. Acid ion water generates as we electrolyze water. Chlorine gas and sodium hydroxide etc. was generated at electrolysis process, and we have toward sterilizing power. Derelicts such as chlorine, phosphorus, sulfur etc. are gathered from a negative ion, and we make acid ion water to + electrode direction in electrolysis. We used a diaphragm in order to disconnect too acid water and alkaline water. We implemented so that the acid water which it came down to three kinds of PWM voltage to PWM (pulse width modulation) control, and implementation method of ph intensity change authorized ph intensity between weak acidity to electrode in strong acidity as we used Microprocessor, and intensity was adjusted successively by PWM control was generated.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.458-466
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• 2007

This study is to evaluate control effects of separation wall by surveying water quality and sewer overflows during dry and wet periods in combined sewer and separated sewer systems. Ravine water from the combined Seokgyo outfall with the separation wall was separated about four times larger than sewage flow during dry periods. The water quality of the combined Seokgyo outfall with separation wall during dry periods is flow weighed average BOD 61 mg/L, the combined Cheonseokgyo outfall without the separation wall is average BOD 71 mg/L, and the separated Pyeongsong center outfall is average BOD 41 mg/L. The BOD concentration in separated outfall form about 57% of the combined outfall, and this means the separated outfall (i.e. storm sewer) is polluted by inflow of sewage. The overflow load of the separated outfall is ten times higher than the combined outfall and its overflow load per rainfall is three times than combined outfall during the wet periods. Therefore, the control plan of overflow load is required in storm sewer. The control effects of the overflow load increased 79% by setting the separation wall in the combined sewer, and showed 27% increase without the separation wall in separated sewer, but forecasted over 80% increase of effects if the separation wall was set.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.251-258
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• 2012

This study was conducted to analyze field inspection results of erosion control facilities within national forests and to suggest maintenance and management plan of erosion control facilities. The objects amounted to a total of 1,628 locations, comprising 308 erosion control dams and 1,320 erosion control areas (1,269.05 ha). The field inspections were conducted during March-June each year. The erosion control dams inspected were constructed during 1991-2005, with 96.4% of them, or 297 dams, constructed in or after 2000. The erosion control areas were constructed during 1986-2005, with 68.6% of them, or 903 areas, constructed in or after 2000. As for erosion control dams, there were 205 concrete erosion control dams and 68 concrete with boulder pitching erosion control dams, respectively, with 296 out of a total of 308 erosion control dams in a good condition. As for erosion control areas, there were many erosion control structures using stone masonry works and gabions, with 1,245 out of a total of 1,320 (94.3%) erosion control areas in a good condition. Overall, erosion control facilities within national forests were in a good condition, amply fulfilling their functions. As for erosion control facilities in a bad condition, they must be made to accomplish the goals of erosion control works through supplementation and repairs without fail. In addition, for the systematic maintenance and management of existing erosion control facilities and erosion control facilities constructed in the future as part of erosion control works, the construction of an erosion control facility management system is urgently needed.

• Journal of Periodontal and Implant Science
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• v.34 no.3
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• pp.659-669
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• 2004

The aim of this study was to evaluate the clinical efficacy of mouthrinses prepared by sterilized water-generating $device(Purister^{(R)})$ on the control of gingivitis and incipient periodontitis when it was used as a adjunctives to the mechanical plaque control. 40 healthy patients with gingivitis or incipient periodontitis were divided into two groups. Patients in the experimental group use mouthrinses prepared by sterilized water-generating $device(Purister^{(R)})$ after tooth brushing while patients in the control group do only tooth brushing for plaque control. All patients received scaling and tooth brushing instruction. 1 week after scaling was set as baseline. Probing pocket depth, clinical attachment level, and bleeding on probing were scored at baseline, 4 weeks. Gingival index and plaque index were scored at baseline, 2 weeks, and 4 weeks. The results were as follows: 1. In the experimental group, gingival index, plaque index, probing pocket depth, and clinical attachment level showed statistically significant decrease, but in the control group, significant increase(p<0.05). 2. There was no significant difference between the experimental and the control group in bleeding on probing, but significant decrease in the experimental group and Significant increase in the control group In a time-dependent manner(p <0.05). From these results, it can be concluded that regular use of mouthrinses prepared by sterilized water-generating $device(Purister^{(R)})$ as adjunctives of mechanical plaque control, may be effective to prevent and treat gingivitis and incipient periodontitis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.295-305
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• 1993

The purpose of this study is to investigate the theoretical methodology for development of an water quality management system with the optimal control of dilution water and point sources in streams. For the development of objective function and constraints, the control vectors are defined with stream inflows and concentrations of effluents at water treatment plant, and the state vectors are defined with water quality parameters such as DO, $BOD_5$, COD and SS concentrations. The applied system solution technique is augmented Lagrangian technique. The developed water quality optimal management methodology was applied to a case study at the Musim stream in Cheong-ju city. The results of the application show that the methodology is suitable for the comprehensive analysis of polluted water systems, and will be utilized to more useful operation of limited water resources in Korean streams.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1304-1310
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• 2015

In remote islands, due to expense of existing generation systems, installation of photovoltaic cells (PVs) and wind turbines has a chance of reducing generation costs. However, in island power systems, even short-term power fluctuations change the frequency of grids because of their small inertia constant. In order to compensate power fluctuations, the authors proposed the power consumption control of pumps which send water to tanks. The power control doesn’t affect water users’ convenience as long as tanks hold water. Based on experimental characteristics of a pump system, this paper shows methods to determine reference power consumption of the system with compensation for short-term PV fluctuations while satisfying water demand. One method uses a PI controller and the other method calculates reference power consumption from water flow reference. Simulations with a PV and a pump system are carried out to find optimum parameters and to compare the methods. Results show that both PI control method and water flow calculation method are useful for satisfying the water demand constraint. The water demand constraint has a little impact to suppression of the short-term power fluctuation in this condition.