• Journal of Climate Change Research
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• v.4 no.3
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• pp.245-254
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• 2013

Korea government promote renewable energy as the core of their energy matrix to break the dependence and reduce greenhouse effects. This study analyzes the economic assessment of Solid Refuse Fuel project in urban area, considering the marginal external costs of air pollution in this area. Assessment index defined as costs (i.e., construction cost, operation cost) and benefit (margin, external cost) data which is located in Sudokwon landfill site. The result indicates that cost-benefit analysis of SRF is calculated as 1.0. In addition, SRF project is very sensitive about electric power selling price, operating cost and labor cost according to inflation rates. This study shows that the sustainability of SRF project is required the government financial support like investment funds as well as policy support. Variability analysis of SRF economic assessment due to renewable energy can be used for making policies in various fields such as waste and public energy field.

• Journal of the Korean Geotechnical Society
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• v.35 no.8
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• pp.17-30
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• 2019

Based on pile load test results for various pile types that were constructed in-situ and pile design data of prebored PHC piles, the ratio of skin friction to total capacity (SRF) was analyzed. A SRF distribution range from the pile load test results for pilot test prebored PHC piles was 42~99% regardless of relative penetration lengths, soil types, and pile load test types. However, a SRF distribution range from the pile design data for prebored PHC piles was 20~53% regardless of relative penetration lengths and pile diameters. Also, a SRF distribution range from the restrike dynamic pile load test results for pretest working prebored PHC piles was a scattered range of 4~83% regardless of pile diameters, relative penetration lengths and soil types. The scattered SRF of pretest working piles was caused to the quality control issue on the filling of cement milk around piles and this quality control issue should be improved. The average SRF calculated by the current design method was estimated to be 2.2 times lower than the average SRF of the pilot test piles. It is because skin friction resistance is calculated at a very low level. Therefore, a new design method for skin friction will be proposed based on this study.

• The Korean Journal of Zoology
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• v.14 no.2
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• pp.75-84
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• 1971

Genetic analysis of a new wing mutant, Surf wings (Srf), was performed. Mutant flies were extracted from a wild population of Drosophila melanogaster at the vicinity of Atomic Energy Research Institute, Seoul in August-September 1969. 1. The distal half of wings of heterozygotes (Srf/+) turned upwards about 40 degree from body axis, but flying ability was not disturbed. They overlap Cy in low frequency when they are grown below $22^{\circ}C$. This resembles with Si or j series, but wing margins are not rolled and diversed. Postscutellars are erected slightly, but they, in general, are not crossed. Any other external pleiotropic effects were not observed. 2. Penetrance and expressivity of both sexes are not complete. Their extents are variable with sex and temperature. These characters show maximum tendencies when the development is made at $22^{\circ}C$ (female: P = 0.996, E = 0.932, male:P = 0.961, E = 0.698). 3. The preliminary locus of Srf was determined to be 66.8 on the right arm of second chromosome by using recessive maker gene cn bw. 4. The homozygous flies(Srf/Srf) have shown perfect lethality. The heterozygotes (Srf/+), on the other hand, have shown to be viable and fertile. Srf chromosomes are kept in a balanced lethal system with Pm chromosomes which are associated with inversions. Hence, it is partially reasonable to suppose that Srf may persist in a natural population by the same mechanism. 5. Allelism test with Cy was also conducted. The fact that combination with Cy in the trans-phase (+ Srf/Cy +) is viable in contrast to the lethality of Srf/Srf and Pm/Pm indicates that Srf and Cy are not functionally allelic.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.874-880
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• 2007

Capillary Suction Time(CST) and Specific Resistance to Filtration(SRF) were commonly used to evaluate the sludge dewatering behaviors. A coupled equation was developed through the mathematical theory which represented both CST and SRF as the physical filterability of the ultrasonically treated sludge. The model for coupling CST and SRF includes both equipment variables and variables related to sludge characteristics, and verified with the results from experiments. The results of the theoretical and experimental study showed that a good correlation relationship among dewaterability indices.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.455-463
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• 2021

This study investigated the biomass content of fluff type SRF(Solid refuse fuel) operated in B city according to the physical composition. As a result of analyzing the physical composition of SRF, it was investigated that papers 25.2%, fiber 15.1%, vinyl·plastics 42.6%, woods 9.4%, rubbers 1.5%, diapers 3.2% and incombustibles 3.0%. The average of ash and combustible content of SRF was 10.5% and 89.5%, and the higher the proportion of paper and wood, the lower proportion of ash. In addition, the biomass of SRF is 24.9%~58.0%, with an average of 42.6%.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.95-103
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• 2016

The government is trying to expanding the manufacture and utilization of solid refuse fuel (SRF) facilities in order to mitigate greenhouse gases reducing and eco-friendly waste-to-energy recovery. In this regard, this study attempts to look into the economic effects of expanding the manufacture and utilization of SRF facilities by applying an inter-industry analysis using a 2014 input-output table. Specifically, by applying the demand-driven model presents the results for the production-inducing effect, value-added creation effect, and employment-inducing effect. In particular, this study attempted to redefine for the SRF. In addition, it was accessed by exogenous around the manufacture and utilization of SRF sector. The results show that production-inducing effect and value-added creation effect of expanding the manufacture and utilization of SRF facilities for the investment of 1.0 won are estimated to be 1.9993 and 0.6747, respectively. The employment-inducing effect of one billion of investment in the expanding the manufacture and utilization of SRF facilities is computed to be 11.1982 persons. This information can be utilized in predicting the economic effects of the manufacture and utilization of SRF.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.6
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• pp.656-665
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• 2012

Recently, yearly production of SRF (Solid Recovered Fuel) as an alternative fuel has been rapidly increasing because of the limited waste disposal, rise in oil prices and reduction of greenhouse gas emission. However, SRF using facilities are excluded from the National Air Pollutant Emission Estimation because SRF using facilities are not yet included among the SCC (Source Classification Code). The purpose of this research was to estimate the emission and emission factor of SRF using facilities' PM and $NO_x$, in order to investigate whether or not they are included in the National Air Pollutant Emission Estimation. The emission factors of SRF using facilities' PM and $NO_x$ are calculated as 0.216 kg/ton, and 3.970 kg/ton, and the emission was estimated based on the yearly total SRF usage of 2011. The results above was 18.7% for PM and 12.8% for $NO_x$ emissions from combustion facility (SCC2) in manufacturing industry combustion (SCC1) of CAPSS. If CAPSS estimate the emission by adding SCC on unlisted SRF in case of Boiler (SCC3) fuel, both PM and $NO_x$'s emissions would increase by 15.8% and 11.3% compare to the emissions for the existing combustion facility. As a result, emissions caused by SRF should be considered when calculating the National Air Pollutant Emission Estimation. In addition, further researches to develop emission factor and improve subdivided SCC should be done in the future, for the accurate and reliable estimation of National Emission.

• Journal of KSNVE
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• v.7 no.5
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• pp.811-817
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• 1997

This paper is concerned with the active vibration controller design for the grid structure based on the positive position feedback (PPF) and the strain rate feedback (SRF) control. A new control methodology by the combination of the PPF and SRF control can suppress all the modes of the structure theoretically and can be easily implemented with analog circuits. The underlying concept for the design of the new controller is that the SRF controller stabilizes the modes higher than the second mode and the PPF controller stabilizes the fundamental mode which is destabilized by the SRF controller. In order for the new controller to be implemented succesfully, the collocated control is necessary. To this end, the piezoceramic sensor and actuator are located as close as possible, thus realizing the nearly collocated control. The combined PPF and ARF controller proves its effectiveness by experiments.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.87-90
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• 1987

This paper gives the Sonic Range Finder(SRF) Array which detects the unknown obstacles on the mobile robot's path. This SRF Array gives mobile robot's circumstance information wider, processes and transfers them to the locomotion module to construct the modify path. In this system, 8 pairs of the 40 KHz ultrasonic sensors constitute the SRF Array, including a pair of reference sensors to correct the errors, 4051 analog multiplexer and demultiplexer swtch the sensor with time and 8031-on chip micro computer controls processes the data and communication the others.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.747-756
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• 1995

To find out the optimum application method of slow-releasing fertilizer(SRF) and conventional fertilizer(CF) with different fertilization rate under two culture methods[l0-day old seedling machine transplanting(MT) and direct-sowing on dry paddy(DS)] in the south-western region(clay loam soil) of Korea, used were Chosun slow-releasing fertilizer(silicate latex coated fertilizer: N-P$_2$O$_{5}$-K$_2$O =18-12-13) and conventional fertilizer. Plant height and number of tillers with different two culture methods were higher at MT than DS in early growth. The ratio of dry weight in heading stage was higher at CF than SRF in MT than DS and especially, SRF 80% + CF 20% than SRF 100% or CF 100%. Leaf area index (LAI) in heading stage was higher at CF in MT but higher at SRF in DS than their counterparts. Chlorophyll content was higher at SRF than in CF expect for heading stage(HS), especially in DS. It was highest at HS in CF without its difference during maximum tillering stage(MTS) and panicle formation stage(PFS), while highest at PFS in SRF with tendency of gradual increase and decrease before and after PFS, respectively. Heading was delayed 2~3 days at SRF in two cultrue methods and 4~5 days at SRF in DS in comparison with CF in MT with delay of 2 days at DS compared with MT. Culm length was longer at CF in MT and at SRF in DS than their counterparts. Panicle number per m was more at SRF and in DS. Filled grain ratio was higher at CF and in MT. Yield was obtained 101 and 100% at 100% and 80% level of SRF in DS respectively, and 96% at 80% level of CF in MT, compared with conventional application method (516kg /l0a), and increased 2~4% at DS and 0~3% at MT in SRF. Yield was high in order of 100%(SRF) =80%(SRF) + 20%(CF) > 100%(SRF) + 20%(CF) > 80%(SRF) at MT and 80%(SRF) + 20%(CF) =100%(SRF) > 80%(SRF) =100%(SRF) + 20%(CF) at DS.