• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.233-235
• /
• 2004

Operation of wind turbines has impacts on the voltage quantity at the connected electricity network. Increasing penetration of wind energy makes necessary to study the power quality regarding voltage variations(sag, swell, interruption) and presence of harmonics in the id. This paper investigates the voltage quality of low voltage customers connected to wind generation system. To study the influences of wind power generation to low voltage power system, voltage data are collected in three house using PQM(Power Quality Monitoring) equipment during one month and analyzed regarding voltage variation and harmonics

• Journal of the Korean Society for Nondestructive Testing
• /
• v.29 no.1
• /
• pp.10-14
• /
• 2009

Heat generation mechanism of ultrasound infrared thermography is still not well understood, yet and there are two reliable assumptions of heat generation, friction and thermo-mechanical effect. This paper investigates the principal cause of heat generation at fatigue crack with experimental and numerical approach. Our results show most of heat generation is contributed by friction between crack interface and thermo-mechanical effect is a negligible quantity.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.10
• /
• pp.28-37
• /
• 2011

Though Korea has introduced CBP(Cost Based pool) power trading system since 2001, long-term Generation system planning has been executed by government for Cost minimization every 2 years. Until currently the model which is used for Generation system planning and best-mix only considers cost minimization and total yearly or quarterly electricity demand every year. In a view point of one day power supply operation, technical characteristics, like the ramp up/down rate of total generation system, minimum up/down time and GFRQ(Governor Free Response Quantity), are very important. this paper analyzes Optimal Fuel-Mix for 2022 Korea generation system satisfying these constraints of each fuel type and considering pump storage plants, construction cost and $CO_2$ emission charge Using MILP(Mixed Integer Linear Programming) method. Also the sensitivity analysis which follows in future power industry environmental change accomplished.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.53 no.5
• /
• pp.302-307
• /
• 2004

As deregulation of power industry is becoming a reality, there has been an intense interest in the strategic bidding for suppliers to maximize their profits. The profit gained by a supplier is related not only to its energy-price bid curve but also to its submitted operational parameters such as generation capacity, etc. So suppliers are willing to use those strategic parameters that can be manipulated by themselves and are effective to their profit. This paper deals with the competition model with compound strategies: generation capacity and bidding curve. The parameter space is modeled by dividing into the two strategies, so the problem is made up of the four types of sub-game in a two player game. This paper analyzes the global Nash Equilibrium (NE) over the whole divisions by computing the sub-game NEs in some divisions and by deriving the best response curves which have discontinuities in other divisions. The global NE is shown to correspond to the Cournot NE where the quantity variable is realized by a constraints of a generation capacity.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.101-104
• /
• 2009

In this paper, it's described the techniques for the analysis of corona generated in open live parts of electric facilities. At needle-plane electrodes, when the voltage increased($0{\sim}70kV$, ramping 10kV) using the high voltage generation system(HIPOTRINICS $0{\sim}200kV$, USA), it's generated the partial discharge. There are compared between UV detected image and PD quantity. As these results, UV areas and gains are normalized. And electric facilities are evaluated the 5 steps such as 'good', 'recognition', 'check', 'inspection', 'change(replacement)'.

• Journal of environmental and Sanitary engineering
• /
• v.13 no.3
• /
• pp.148-157
• /
• 1998

Leachate is a result of the percolation of precipitation, uncontrolled runoff, and irrigation water into the landfill and can also include water initially contained in the waste as well as infiltrating groundwater. Behaviour of leachate by rainfall was studied to evaluate the variation of leachate generation and contaminants by rainfall in Sudokwon Landfill from January 1998 to October 1998. The quantity of leachate generated was measured with a flow meter, and the concentrations $BOD_5$, CODcr, T-N, $NE_3-N$, SS of leachate were also measured. Principal outcome obtained in this study are as follows : the quantity of leachate generated was the highest on August, the highest leachate generation volume in this period was 11,913㎥ and the lowest was $6,261m^3$. Although the similar amount of precipitation of 80mm applied to the two samples, there were difference in leachate generation due to precipitation duration, precipitation frequency, wet condition of solid wastes. As the result of regression analysis, the correlation coefficients(r) between the quantity of leachate generated and precipitation were 0.823, 0.976 between $BOD_5$ and CODcr, 0.992 between T-N and $NE_3-N$. As the quantity of leachate generated increased 48%, the concentration of $BOD_5$ and CODcr decreased 51% and 50% respectively. Therefore it was showed that the pollutant concentrations in leachate were diluted by precipitation. The concentrations of $BOD_5$ and COBcr in the rainy season were 2000~4000mg/1, 4000~6000mg/1 respectively, and 1000~3000 mg/1, 3000~5000 mg/l in the dry season. The loading of SS, $BOD_5$, CODcr(kg/month) on July was increased by 2.9 times, 2.8 times, 2.2 times with a basis on March. Therefore countermeasure of treatment facilities according to increase of loading by rainfall in summer is necessary.

• Journal of the Korean Professional Engineers Association
• /
• v.19 no.1
• /
• pp.12-24
• /
• 1986

The number of visiters to Bukhan Mt. national park, generation quantity of solid waste and collection system were researched to consider a counterplan for the pollution control of the national park and study for developing the effective treatment of solid waste was tried through the proximate analysis of each component containing. Results obtained in this study were summerized as follows; The great part of visitors go on an excursion to the Bukhan Mt. national park during July and August and also, the solid waste was generated nearly a half of the total amount at the same period. The major collection facilities in the national park were waste basket and incineration box. But the incineration box was too large in volume and very far in distance, and its collection period was irregular, so it was cause to the congestion of solid waste and bad smell and dirty. Therefore, to complete collection of solid waste, we must set up the waste basket which able to find within 40～50m from the origination place of solid waste and induce the visitors to throw the solid waste. It was obtained as moisture content: 48.5 wt%, volatile solid: 28.4wt％, fixed solid: 23.1 wt％, lower heating value: 1,320kca1/kg from experimental analysis of solid waste. According to this analysis, the incineration operation is possible, but the generation quantity of solid waste was too small to construct incineration plant for heat recovery. It was found that it is suitable for the aerobic composting by mixing with the night soil which generate in the national park after the recovery of resources such as metals, glasses and plastics.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.571-576
• /
• 2006

We review work performed by our group and collaborators in the area of exciton formation. There are three components: (i) measurement of singlet fractions, (ii) analysis of magnetic resonance measurements, and (iii) models of exciton formation. We find that the fraction of singlet excitons is a controllable quantity, pointing the way to a new generation of all-fluorescent organic light emitting devices.

• KIEAE Journal
• /
• v.14 no.1
• /
• pp.67-74
• /
• 2014

There have distinctly been no the installation criteria and maintenance management of BIPV systems, although the BIPV market is consistently going on increasing. In addition, consideration of the BIPV generation quantity which has been installed at several diverse places is currently almost behind within region in Korea. Therefore, the main aim of this study is to evaluate the BIPV generation and to be base data of reducing rate depending on regional installation angles using PVpro which was verified by measured data. Various conditions were an angle of inclination and azimuth under six major cities: Seoul, Daejeon, Daegu, Busan, Gwangju, Jeju-si for the BIPV system generation analysis. As the results, Seoul showed the lowest BIPV generation: 1,054kWh/kWp.year, and Jeju-si have 5percent more generation: 1,108.0kWh/kWp.year than Seoul on horizontal plane. Gwangju and Daejeon turned out to have similar generation of result, and Busan showed the highest generation: 1,193.5kWh/kWp.year, which was increased by over 13percent from Seoul on horizontal plane. Another result, decreasing rate of BIPV generation depending on regional included angle indicate that the best position was located on azimuth: $0^{\circ}$(The south side) following the horizontal position(an angle of inclination: $30^{\circ}$). And the direction on a south vertical position(azimuth: $0^{\circ}$, an angle of inclination: $90^{\circ}$) then turned out reducing rate about 40percent compared with the best one. Therefore, these results would be used to identify the installation angle of the BIPV module as an appropriate position.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.9
• /
• pp.15-25
• /
• 2010

The main objective of this study was to offer informations about long-term seepage behavioral characteristics and to find a leakage safety management method for Juam Dam and Imha Dam, a central cored rockfill dams in Korea by the evaluating the automatically monitored leakage data. In the water leakage monitoring of fill dam, the generation of abnormal water leakage is difficult to directly detect due to the effect of outside factors such as the component of rainfall inherent in the observation value. Therefore, conventionally estimation methods of water leakage quantity were applied by multiple regression analysis considering reservoir water level, rainfall, etc.. However, the estimated error of rainfall component is relatively big in these method. This paper identifies the seepage characteristic of each dams which is not directly affected by rainfall through the hydrograph separation analysis and 3 dimensional analytical method, and thinks a leakage management method. It was noticed that two dams had site specific seepage behaviour features and were in stable state with the decreasing leakage quantity. It was also found that hydrograph separation method might be applicable to leakage safety management method.