• Journal of the Korean Society of Marine Environment & Safety
• /
• v.17 no.2
• /
• pp.161-166
• /
• 2011

In this study, design of hull and test of model boat were carried out with electric propulsion small boat driven by photo-voltaic energy. The shape of boat was made with catamaran type by considering the ship's stability, the light-receiving area from solar. According to calculation, when speed of model boat is 5 knots, it was estimated the available power for propulsion with 1.1[hp]. However, the natural energy such as solar energy is strictly dependent upon the climate conditions so the real boat speed is slightly lower than the estimated value.

• Journal of the Korean Solar Energy Society
• /
• v.35 no.2
• /
• pp.85-91
• /
• 2015

In this study, energy performance analysis of houses in zero energy demonstration town(ZeT) was carried out using the monitoring results. This ZeT was composed 29 zero energy individual houses(ZeH) which were applied passive as well as active technologies. The results are as follows. (1) Residents are generally considered to have been lacking basic mind to save energy, (2) In particular, average yearly total energy consumption per house is 12,834 kWh and specific heating energy is $53.2kWh/m^2{\cdot}yr$ which is higher than that of passive house. This is because of one of the reason just pointed out in subsection (1). (3) Most part of the residual energy load are supplied with only renewable energy, but not operating energy for geothermal heat pump which is use of cheap electricity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.05a
• /
• pp.187-190
• /
• 2011

Until now, water pollution environmental monitoring system has been used at to acquire and measure data for streams and rivers. Recently coastal and marine environment monitoring system is becoming most important and urgent thing. The realtime automatic coastal and marine environment monitoring system using CDMA data transmission technique is developed in this study. The Embedded field server is designed and developed to acquire and measure underwater environment information such as pH, DO, water temperature using the water quality sensor. The obtained data is sent to the server via CDMA modem connected to the embedded field server and stored in database. Our purpose is to provide and monitor underwater environment information with CDMA communication in coastal areas.

• Korean Journal of Optics and Photonics
• /
• v.31 no.6
• /
• pp.259-267
• /
• 2020

We evaluate the degradation of receiver sensitivity induced by direct and indirect exposure to solar irradiance in free-space optical communication systems. For this purpose, we calculate the variances of numerous noise components arising from solar irradiance, and then estimate the receiver sensitivity penalties for intensity-modulation/direct-detection and coherent systems. The results show that the penalties are less than 1.3 dB when indirect sunlight impinges on the detector, regardless of the system. However, the sensitivity penalties are estimated to be larger than 30 dB when the sunlight is directly incident upon the receiver. These penalties are barely reduced if we insert an optical polarizer, or if we adjust the bandwidth of an optical filter at the receiver to be as narrow as the signal's bandwidth.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2009.06a
• /
• pp.397-401
• /
• 2009

On the crisis of international economy, the government is making an effort to seek economic growing motivation with the method of overcoming economic crisis and 'low carbon green growth'. Furthermore, to promote maritime vessel traffic service related inefficient energy wastage was revealed and eco-friendly alternative energy was accepted because of high price of oil in the beginning of 2008. In this situation, I'm going to discuss the possibility of eco-friendly energy system in maritime vessel traffic service with the way of cutting the budget and expansion of solar power generation system which was promoted to meet governmental 'energy saving plan for high price of oil'.

• Journal of the Korean Solar Energy Society
• /
• v.25 no.3
• /
• pp.69-75
• /
• 2005

The PV-Solarwall system has been introduced as a promising alternative to harness solar energy for both heating applications and electricity generation simultaneously. The system comprises a PV solar panel(for electricity generation). In addition, the solarwall incorporates a fan strategically located behind the PV panel to bring the warm and fresh air from the solarwall into the room. Because of its location and convective cooling principle, the fan also serves to reduce the operating temperature of the PV panel thereby increasing its efficiency. So this PV-Solarwall system holds much promise for saving heating and electricity costs compared with a PV system without solarwall. In particular, by controlling the tilt angle of the entire PV-Solarwall system between $0^{\circ}$(horizontal) and $90^{\circ}$(vertical), the performance of the system can be further evaluated. It is expected that the range of tilt angle PV-Solarwall between $40^{\circ}$ and $50^{\circ}$ will improve the output of the system.

• Journal of Korean Association for Spatial Structures
• /
• v.16 no.1
• /
• pp.65-72
• /
• 2016

Aerodynamic performance of solar wing system has been evaluated through wind tunnel test. The test model has 12 panels, each supported by 2 cables. The panels were installed horizontally flat, and gaps between panels were set constant. Sag ratios of 2% and 5%, and wind directions between $0^{\circ}$ and $90^{\circ}$ were considered. Mass of test model was determined considering the mass of full scale model, and Froude number and Elastic parameter were satisfied by adjusting the mean wind speed. From the wind tunnel test, it was found that the aerodynamic performance of the solar wing system is very dependent on the wind directions and sag ratios. When the sag was 2%, the fluctuating displacements between the wind directions of $0^{\circ}$ and $30^{\circ}$ increase proportionally to the square of the mean wind speed, implying buffeting-like vibration and a sudden increase in fluctuating displacement was found at large mean wind speed for the wind directions larger than $40^{\circ}$. When the wind direction was larger than $60^{\circ}$, a sudden increase was found both at low and large mean wind speed. When the sag ratio is 5%, distribution of mean displacements is different from that of sag ratio of 2%, and the fluctuating displacements show very different trend from that of sag ratio of 2%.

• Proceedings of the KIPE Conference
• /
• 1999.07a
• /
• pp.569-572
• /
• 1999

As the industry has been growing rapidly, the problem of environmental pollution has been on the rise seriously. In this paper, we used solar cells at the power supply unit of the equipment, which has been sold at present, for measuring the quality of water in order to complement the problem. Also, to get rid of the inconvenience that the examiners must go to the job site, check and collect the polluted water we set the goal at designing the water pollution alarm system which measures the quality of water automatically using one-chip microprocessor and materializing the program.

• Journal of the Korean Solar Energy Society
• /
• v.28 no.6
• /
• pp.87-92
• /
• 2008

Buildings are responsible for approximately 50% of current carbon dioxide emissions. Energy planning at a town and city scale needs a strategic approach, supported by strong planning policies. The purpose of this study was to investigate the urban scale grid-connected photovoltaic(PV) system for urban residential and commercial sector applications. The integration of PV technology into roof of houses is an approach that is being championed in Germany, Japan and United states etc. In the Korea, PV roofing systems already are given the large number of houses which are projected to be built by 2012. However unlike germany and Japan, urban scale grid-connected PV system is not yet installed. The solar city which is installed building-integrated photovoltaic system is available to use of renewable energy sources such as solar to meet demand, instead of fossil fuels, with the goal of realizing an ecologically oriented energy supply.

• Journal of the Korea Society of Computer and Information
• /
• v.19 no.2
• /
• pp.109-115
• /
• 2014

The research on solar energy that we get from nature to cope with energy exhaustion is a very significant and inevitable task for us to do. Along with this, lately, in Korea, as part of new growth engine industry regarding low-carbon green growth, we have selected the LED(Light Emitting Diode) as low power consuming, eco-friendly lighting equipment and have been facilitating research and development on it and creating a variety of new industries utilizing it. What was developed here in this research was the photovoltaic LED lighting system applying lithium polymer batteries equipped with the excellent performance of lithium ion batteries as well as significantly low explosive hazard. Its photovoltaic panel was made to have 100W capacity, and for its power supply system, functional convenience was considered so that it could be equipped with both DC and AC power to be used as household electricity in a variety of ways.