• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.631-636
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• 2011

Stable power supply to a light mounted on a navigational buoy is indispensable factor because unstable power can lead to fatal marine accident. Despite the difference lies between onshore and offshore environment, as well as the power output characteristics, the PV(Photovoltaic) power generation system is designed by the independent onshore power generation system standards. Furthermore, the capacity of PV power generation system does not take into account the structural characteristics of the buoy in the sea. Therefore, the faulty design makes battery over-discharge owing to lack of the power generation and the battery can not supply stable power to the light. This paper introduces a design method for a power system of the PV powered buoy. The data has been acquired for 3 months period, which includes PV-generated electricity, power consumption and battery voltage from experimental buoy. Further, a power management features of the buoy has been analyzed based on the acquired data. From the analysis of the acquired data, it was evident that PV power generation system produces different electric power output depend on its installed environment - land and sea. Based on the analytical result, a design criterion has been proposed for the power system in the navigational buoy.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.171-173
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• 2003

Digital environment that is represented to internet is displacing business way of industry and business achievement way with the fast speed being giving great change on life whole, improve existence business process utilizing internet and Web connection technology, information superhighway to tradition industrialist manufacture and e-transformation's propulsion that wish to maximize productivity and administration efficiency is spread vigorously. In this paper, we wish to accomplish generation equipment's heighten stability and believability through remote monitoring and control of PV system. This paper describes the design of the monitoring system for sensing the monitoring data and indirect controlling of the PV system. Most of the conventional monitoring system depend on the special hardware and software. Basic design goal of monitoring system is to provide the convenience for the user and the portability for the system. In order for the system to fulfill its requirements, it was designed using Labview GUI facility based on the Windows 2000 environment of IBM PC compatible and Add-on card based on the TCP/IP protocol. Advantage of the monitoring system are a personnel expenses curtailment effect, free of the place restriction and unmanned system of the generation plants, etc.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.2
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• pp.100-105
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• 2022

This paper applies the arc detection algorithm to prevent the false detection in photo voltaic series arc detection circuit, which is required not only to detect the series arc quickly, but also not falsely detect the arc for the non-arc noise. For this purpose, this study proposes a rapid and preventive false detection method of single peak noise and short noise signals. First, to prevent false detection by single peak noise, Discrete wavelet transform (DWT)-based characteristic parameters are applied to determine the shape and the amplitude of the noise. In addition, arc fault detection within a few milliseconds is performed with the DWT iterative algorithm to quickly prevent false detection for short noise signals, considering the continuity of serial arc noise. Thus, the method operates not only to detect series arc, but also to avoid false arc detection for peak and short noises. The proposed algorithm is applied to real-time serial arc detection circuit based on the TMS320F28335 DSP. The serial arc detection and peak noise filtering performances are verified in the built simulated arc test facility. Furthermore, the filtering performance of short noise generated through DC switch operation is confirmed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.2
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• pp.186-193
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• 2018

Generally, it is difficult to operate moveable-weir due to the expensive cost of the facility management and manpower consumption. Also, when it is installed in a remote area, there is a problem that the cost of connection for power system increases as well as the operating cost. Therefore, this paper proposes an optimal design algorithm to replace an existing power system with an Eco-friendly power supply system for movable-weir using PCS, PV module and lithium-ion battery. Also, this paper proposes a modeling method of environment-friendly power supply system for a movable-weir based on the PSCAD/EMTDC S/W and implements 5[kW] prototype environment-friendly power supply system. As a result of the performance test using the S/W modeling and the prototype system, it is confirmed that the proposed system has stable characteristics in the independent operation mode and the interconnection mode.

• Journal of the Korean Solar Energy Society
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• v.39 no.6
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• pp.93-112
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• 2019

In this paper, a very new web-based software for renewable energy system (RES) design and economic evaluation was introduced. This solution would provide the precise RES estimation service including not only photovoltaic (PV), wind turbine (WT) and fuel cell (FC) individually but also energy storage system (ESS) as combined forms with PV or WT. The three reasons why we ought to develop it are: First, the standardized tool suitable to the domestic environment for estimating power generation from RES facilities and economic evaluation is required. Secondly, the standardized tool is needed to spread domestic RES supply policy and to promote the new industry in the micro-grid field. The last, the reliability of economic evaluation should be enhanced more for new facilities. To achieve those aims, the weather database of one hundred locations have established and the RES facility database has also constructed. For the energy management, mathematical models for PV, WT, ESS and FC were developed. As a final phase, the analytical process to evaluate economics has performed with field data verification.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.12
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• pp.638-644
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• 2017

Optimal cooling operation algorithm was developed based on a simulation case of a single family house model equipped with renewable energy facility. EnergyPlus simulation results were used as virtual test data. The model contained three energy storage elements: thermal heat capacity of the living room, chilled water storage tank, and battery. Their charging and discharging schedules were optimized so that daily electricity bill became minimal. As an optimization tool, linear programming was considered because it was possible to obtain results in real time. For its adoption, EnergyPlus-based house model had to be linearly approximated. Results of this study revealed that dynamic cooling load of the living room could be approximated by a linear RC model. Scheduling based on the linear programming was then compared to that by a nonlinear optimization algorithm which was made using GenOpt developed by a national lab in USA. They showed quite similar performances. Therefore, linear programming can be a practical solution to optimal operation scheduling if linear dynamic models are tuned to simulate their real equivalents with reasonable accuracy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.5
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• pp.1353-1362
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• 2014

In recent years, numerous environmental problems associated with the excessive use of fossil fuel are taking place. For an alternative energy resource, the importance of renewable energy and the demands of facilities to generate renewable energy are continuously rising. To satisfy such demands, a large number of photovoltaic energy generation structures are constructed and planned with large scale. However, because these facility zones are mostly constructed on land, some troubles are occurred such as rising of construction cost due to the cost of land use, environmental devastation, etc. To solve such problems, the floating type photovoltaic energy generation system using FRP members have been developed in Korea. FRP members are recently available in civil engineering applications due to many advantages such as high strength, corrosion resistance, light weight, etc. and they are suitable to fabricate the floating structures because of their material properties. In this study, the analytical and experimental investigations to evaluate the structural performance of floating PV generation structure and SMC FRP vertical member which is used to fabricate the structure were conducted. The static and dynamic performances of floating PV generation structure are evaluated through the FE analysis and the experiment, respectively. Moreover, the structural safety evaluation and buckling analysis of SMC FRP vertical compression member are also conducted by the FE analysis, and the structural behavior of SMC FRP member under compression and pullout is investigated by the experiments. From this study, it was found that the structural system composed of pultruded FRP and SMC FRP members are safe enough to resist externally applied loads.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.1
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• pp.13-17
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• 2005

We explored a new rough grinding technique on optics materials such as Zerodur. The facility used is a NANOFORM-600 diamond turning machine with a custom grinding module and a range of diamond resin bond wheel. The grinding parameters such as workpiece rotation speed, depth of cut and feed rate were altered while grinding the workpiece surfaces of 20mm in diameter. Surface roughness was measured by Form Talysurf series2. Our target is to define grinding conditions producing the surface roughness smaller than $0.2{\mu}m$ Ra.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.244-254
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• 2009

The hypersensitive reaction (HR) is the most common plant defense reaction against pathogens. HR is produced during both host- and nonhost-incompatible interactions. Several reports suggest that similarities exist between host and nonhost resistances. We assayed the pattern of generation of reactive oxygen species (ROS) and scavenging enzyme activities during nonhost pathogen-plant interactions (Xanthomonas campestris pv. campestris/Capsicum annuum L.) and incompatible host pathogen-plant interactions (Xanthomonas campestris pv. vesicatoria race1/Capsicum annuum L.). Both ${O_2}^-\;and\;H_2O_2 $ accumulated much faster during nonhost resistance when compared to the host resistance. The scavenging enzyme activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were also different during the host- and nonhost-incompatible interactions. CAT activity was much higher during nonhost resistance, and several new isozymes of SOD and POX were detected during nonhost resistance when compared to the host resistance. Lipoxygenase (LOX) activity was higher in host resistance than nonhost resistance during the early stages of infection. Interestingly, the nitric oxide (NO) radical accumulated equal amounts during both host and nonhost resistance at early stages of infection. Further studies are needed to determine the specific pathways underlying these differences between host and nonhost resistance responses.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.953-956
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• 2003

Digital environment that is represented to internet is displacing business way of industry and business achievement way with the fast speed being giving great change on life whole, improve existence business process utilizing internet and Web connection technology, information superhighway to tradition industrialist manufacture and e-transformation's propulsion that wish to maximize productivity and administration efficiency Is spread vigorously. In this paper, we wish to accomplish generation equipment's heighten stability and believability through remote monitoring and control of PV system. This paper describes the design of the monitoring system for sensing the monitoring data and indirect controlling of the PV system. Most of the conventional monitoring system depend on the special hardware and software. Basic design goal of monitoring system is to provide the convenience for the user and the portability for the system. In order for the system to fulfill its requirements, it was designed using Labview GUI facility based on the Windows 2000 environment of IBM PC compatible and Add-on card based on the TCP/IP protocol. Advantage of the monitoring system are a personnel expenses curtailment effect, free of the place restriction and unmanned system of the generation plants, etc..