• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.269-274
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• 2011

A solar cell is primary parts to produce electrical energy from the Sun. And, we can utilize those solar cells as a power generation system in home, factory, and so on. In order to make proper power, the solar cells are configured in series and parallel lay down. In condition of uniform illumination, the solar array will produce an enough power by photovoltaic effects from the solar cells. In case of non-uniform illumination on the solar cells, the power will be dramatically decreased compared to design. Fortunately, there were so many research outputs regarding the illumination effects on solar array. In this work, we tried to find out the non-uniform effects on unit CPV solar cell, because there were no research outputs for unit CPV solar cell considering illumination. The CPV solar cell was used in CPV system to make a power by the Sun. We chosen the triple junction solar cell of GaAsInP2Ge for simulation, which has a 30 % of conversion efficiency. By simulation, we obtained the output performance of CPV solar cells in condition of various illumination by using Hamming Window function. Its performance was degraded by 10 % to 50 % depending illumination conditions.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.59-67
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• 2011

This paper is focused on the effect of indoor temperature rise according to the use of windows and blinds in double skin facade in summer. For the experiment, we set up the mock-up of double skin facede and measuring temperature and solar radiation. Total 7 cases were used for measuring solar transmittance and indoor temperature rise. When the venetian blind was not installed, solar transmittance was 44.5%, and solar transmittance for the case that installed the venetian blind (angle 0) was 22.5%. Cases that opened inner and outdoor windows for ventilation showed lower indoor temperature rise than cases with closed windows. In addition, Case 5 (opened inner and outdoor windows with the venetian blind (angle 0) to reduce solar transmittance) indicated lower indoor temperature rise than Case 3(opened inner and outdoor windows). Consequently, Case 5 which uses inner and outdoor window for ventilation and venetian blind to reduce solar transmittance is the most effective way to reduce indoor temperature rise among all cases tested in this research.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.141-149
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• 2013

Recently, the time in which children moves by car become frequent, they stay longer in the car because leisure life including camping and etc. increased. Children whose physical activities are active were subject to restriction because of the limited car boarding visual space and on security. Because of limited space in cars, domestic and foreign automotive companies show the different glass roof applied in cars that exhibited wide clear view in order to remove tedious and stuffy of children while they stay for a long time inside the car. In addition, the potential probability in which the Smart Car that the IT technology is grafted research and research that it utilizes the door window glass as the display is progressed and which the glass roof can be used as the screen can be sufficient. In this study, the in-vehicle display application case and Smart Devices constellation application were benchmarked. The car glass roof application method of the constellation studying content which performed the user survey for the child by the car with the parents whose movement is frequent and considers the child and fundamental interaction way tried to be drawn and we try to propose.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.131-139
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• 2011

In this paper, we propose a double-faced window printed antenna for aircraft applications. The proposed antenna structure consists of a feeding line and a multi-loop radiator located on different sides of the window to use the limited given-area effectively. The proposed antenna is optimized by the genetic algorithm in conjunction with the FEKO EM simulator. The optimized antenna is built and installed on a 1/10 sized KUH-Surion mock-up and antenna performances such as the reflection coefficient and the radiation patterns are measured. The optimized antenna shows a half power matching bandwidth of about 33 % at 60 MHz and an average bore-sight gain of about -3.49 dBi. To verify the reception capability of the optimized antenna, we simulated the received power according to a flight scenario. The result confirms that the optimized antenna shows a minimum received power level above -60 dBm at a range of 200 km, which is similar to the pole antenna that is currently used as a FM voice antenna for KUH-Surion.

• Korean Journal of Optics and Photonics
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• v.25 no.5
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• pp.239-244
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• 2014

Retro-reflectors have been used for a wide range of applications such as traffic safety, special blinds, optical devices, etc. We analyzed the characteristics of the reflected light of a strap retro-reflector as a function of incidence angle. It is expected that various solar control structures may be designed more quantitatively using the characteristic chart we have prepared.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.116-118
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• 1984

This study was carried out to know the percentage of parasitism and host preference of Haplogonatopus atratus (Dryinidae) in the nymphs of small brown planthopper. The percentages of parasitism in the nymphal stage of planthopper at each generation were $19.2\%$ for overwinterd generation, $10.8\%$ for the 1st generation on barley field and $21.5\%$ for the 2nd generation on paddy field, respectively. The percents of the parasitism for the respective instars were $78.2\%$(3rd), $17.5\%$(End), and $4.2\%$(4th) when various developmental stages of the planthopper had been caged together. No parasitized individual was found for the instars of the 1st, the 5th and the adult.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.4
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• pp.413-420
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• 2010

The ionospheric delay is currently one of the most significant error sources in precise GNSS surveys. The users of single-frequency receivers should apply some kind of ionospheric correction algorithms to remove or model the ionospheric delay. For real-time correction of the ionospheric delay, one can use Klobuchar or NeQuick model provided by navigation messages of GPS and Galileo, respectively. We evaluated the performance of those models by comparing their effectiveness at different seasons and latitudes. For the first test, we computed the vertical total electron content (VTEC) at the permanent GPS site SUWN for four different seasons. As the second test, we picked three sites in Korea (CHLW, SUWN, JEJU) with high, medium, and low latitudes and evaluated the dependency of VTEC on the site latitude. Computed VTEC values were compared with those from the IRI model and Global Ionosphere Maps (GIM). The root-mean-square (RMS) differences of Klobuchar and NeQuick with respect to IRI and GIM were analyzed. As a result, without regard to season and latitude, the RMS differences of NeQuick models were smaller than that of Klobuchar by about 0.01~3.50 TECU.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.46-49
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• 2005

Curdlan, a natural $\beta-1,3-glucan,$ has been studied as drug carrier due to its unique properties including its thermal gelling characters. In this study, curdlan was chemically acetylated for pH-sensitive drug delivery. Curdlan acetate microspheres(CAMs) were prepared by the solvent evaporation method. The size of the CAMs was below $200{\mu}m.$ The drug loading efficiency of microspheres was approximately $58.44\%$. In the swelling test, the CAMs showed pH-sensitive behavior. The swelling capacity of microspheres at pH 7.4 was much greater than at pH 1.4. Also, release rate of indomethacin(IND) at pH 7.4 from the CAMs was faster than that at pH 1.4. Therefore the CAMs have potential for the controlled release of IND over an extended period of time.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.2
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• pp.257-263
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• 2006

With the ever increasing demand for data communication methods, powerline communication has become in interesting alternative method for data communication in home networking. For the purpose of home safety, several sensors will be installed at door, windows, gas alarm, etc. When considering home networking, the sensor data as well as other types of data should be supported in powerline communication. Usually the sensor data do not have priority over isochronous traffics (voice, video traffic), but in the case of urgent situation at home, the data of sensor being aware of the situation should be transmitted earlier than others. The objective in this paper is to develop a method for supporting an urgent data in home networking using powerline communication. We propose a modified algorithm of HomePlug 1.0 and show the results of computer simulation.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.241-245
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• 2009

Because of the heat island phenomenon and sea wind, there can be thermal conditions' differences around buildings at downtown and coastal area respectively in coastal city, like Busan, Incheon, Mokpo. For the final purpose of the buildings' energy saving design and operation considering of above mentioned environments differences, energy consumption including heating and cooling loads, electric loads are necessary to be accumulated and analyzed in as the database. As a part of this concept, this study aims to survey and analyze each loads of 22 apartments which has at least 100 households respectively and is located at Yeongdo island, Busan, Korea It is cleared that despite the residents living in this district can use sea wind as a natural ventilation and/or cooling methods, they mainly depends on the electric-driven air-conditioners for cooling with window-closed because of anti-salt problems of the sea wind. This leads the maximum power consumption of the surveyed-22-apartments to be appeared in August like that of inland buildings.