• Journal of Korean Society of Water and Wastewater
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• v.18 no.1
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• Environmental Engineering Research
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• v.17 no.1
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• pp.41-46
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• 2012

In this study, the performance of new digestion system (NDS) for the treatment of food waste leachate was evaluated. The food waste leachate was fed intermittently to an anaerobic reactor at increasing steps of 3.3 L/day (hydraulic retention time [HRT] = 30 day), 5 L/day (HRT = 20 day), and finally 10 L/day (HRT = 10 day). In the anaerobic reactor, the pH and alkalinity were maintained at 7.6 to 8.2 and 8,940-14,400 mg/L, respectively. Maximum methane yield determined to be 0.686L $CH_4$/g volatile solids (VS) containing HRT over 20 day. In the digester, 102,328 mg chemical oxygen demand (COD)/L was removed to produce 350 L/day (70% of the total) of biogas, but in the digested sludge reduction (DSR) unit, only 3,471 mg COD/L was removed with a biogas production of 158 L/day. Without adding any chemicals, 25% of total nitrogen (TN) and 31% of total phosphorus (TP) were removed after the DSR, while only 48% of TN and 32% of TP were removed in the nitrogen, phosphorus, and heavy metals (NPHM) removal unit. Total removal of TN was 73% and total removal of TP was 63%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6C
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• pp.512-519
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• 2012

To design a new Navigation Satellite System signal, we should analyze the influence of inter-system interference to existing Global Navigation Satellite Systems(GNSS). Various GNSS systems such as GSP, GALILEO, Compass use same frequence band and incur inter-system interference due to the overlapping spectrums. In this paper, we consider L2 Band for new Navigation Satellite System and propose the BOCcos(15,2.5) signal what has least Spectral Separation Coefficient with GPS L2 system. Assuming 4 stationary satellite over Korea, we simulate the effect of interference. As a result, proposed system shows very small mutual interference effect and negligible effective signal to noise ratio(SNR) loss, compared to the interferences between GNSS systems in L1 Band.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.91-100
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• 1998

This paper is to study on rating system of some shrubs for pedestrian control with concentrate upon the density of branch. It was usd that Hibiscus syricacus L., Spiraea prunifolia var. simpliciflora Nak, Ligustrum obtusifolium S. et Z., Callicarpa dichotoma Raeusch., Rhoododendron mucrionulatum Turcz., Syringa vulgaris L., Weigela subsessilis L. H. Bailey, Cercis chinensis bunge, Forsythia koreana Nak., Euonymus alatus Sieb, Chaenomeles speciosa Nak., orbaria sorbifolia var. stellipila Max., Deutzia parviflora Bunge, Kerria japonica De Candolle, Prunus tomentosa Thunberg ex Murray, Purunus grandulosa for. albiplena Koehne. Shrubs are invesitgated ito the density of branch, the power of sprout, height, a rate of growth, hardness of naturalizaton, crown width and existence of thorns. Shrubs belonged to high group of rating system for pedestrian control were Euonymus alatus Sieb, Purunus grandulosa for. albiplena Koehne, Chaenomeles speciosa Nak., Spiraea prunifolia var. simpliciflora Nak., Prunus tomentosa Thunberg ex Murray, Rhododendron mucronulatum Turcz., Hibiscus syricacus L., Ligustrum obtusifolium S. et Z., Syringa vulgaris L., Weigela subsessilis L.H.Bailey.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.17-19
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• 2000

This paper deals with Load Flow Program for client/server system. Clients play roles of input and output of the data. The client upload input-data file to the server which takes the part of the function of solving the Load Flow. The developed LF COM(Component Object Model) carry out solving the Load Flow and saving the result and the input data to DataBase. It proved the developed System to be compatible through the Case Study.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.1
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• pp.91-101
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• 2014

Three water treatment plants(WTPs) in Jeju island whose source water have different characteristics from those of the mainland of Korea were investigated. Coefficients of bulk water decay($k_b$) of free chlorine at $5^{\circ}C$ for ES, GJ, NW WTPs were $-0.003hr^{-1}$, $-0.002hr^{-1}$ and $-0.001hr^{-1}$ respectively based on bottle tests. To simulate the free chlorine variations in the distribution system using EPANET, ES WTP was chosen. Free chlorine concentrations of several sites were less than the drinking water quality standards(i.e., 0.1 mg/L); E5(0.03 mg/L), E6(0.02 mg/L), W21(0.02 mg/L) and W25(0.03 mg/L). To maintain more than 0.1 mg/L of free chlorine in the distribution system, at least 1.9 mg/L of chlorine was needed at the WTP, which suggested rechlorination was needed to supply palatable tap water to customers. Two sites, one that diverged into E5 and E6 in the east-line and another located before E21 in the west-line were selected for the appropriate rechlorination locations. The recommended rechlorination dosages were 0.42 mg/L for the east and 0.27 mg/L for the west. The simulated results indicated that the free chlorine could be reduced to 0.4 mg/L at the WTP with rechlorination, and taps with excessive free chlorine could be more stabilized(i.e., 0.1~0.4 mg/L).

• Journal of Korean Society of Environmental Engineers
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• v.39 no.4
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• pp.208-213
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• 2017

In this study, four inorganic pollutants (cadmium, chromium, manganese, lead), that could cause contamination events in drinking water distribution system, were selected and batch tests were carried out to determine the "minimum response concentration (MRC)", a part of Korean Contamination Warning system establishment. As the results, the minimum response concentration of cadmium was found to be 0.05 to 0.08 mg/L (0.005 mg/L : water quality standard) and that of chrome was 0.03 mg/L (0.05 mg/L). And the minimum reaction concentration was 0.005 mg/L for manganese (0.05 mg / L for water quality) and 0.02~0.08 mg/L for lead (0.01 mg/L).

• The Korean Journal of Community Living Science
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• v.15 no.1
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• pp.77-83
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• 2004

The aim of this study was to investigate the effects of L-carnitine on the components of serum and liver and the effects on the anti-oxidant system. For this purpose, five experimental groups were setup. For fat source, perilla oil enough with unsaturated fatty acid and beeftallow enough with saturated fatty acid were supplemented together with L-carnitine to the rats. Five experimental groups kept eight Sprague-Dawley rats respectively, They were co group supplemented with basic diet or AIN-93, PO group supplemented with perilla oil, POC group supplemented with perilla oil and L-carnitine, BT group supplemented with beeftallow, and BTC group supplemented with beeftallow and L- carnitine. The results are. 1) Weight gain, food intake and FER were not different significantly among the experimental groups. 2) Significant difference was observed in serum total lipid(P<0.05), serum triglyceride(P<0.05), serum total cholesterol (P<0.05)and serum LDL cholesterol(P<0.05). Serum total lipid and serum triglyceride were significantly low in the groups supplemented with L-carnitine. Serum total cholesterol showed difference with the supplementation of L-carnitine in BTC only. LDL cholesterol showed no significant difference with the supplementation of L-carnatine, but total values of LDL-cholesterol were high in groups supplemented with beeftallow. 3) Total cholesterol in liver was low in POC group with the supplementation of L-carnitine however, there was no difference in BTC group with the supplementation of L-carnitine. In summary, dietary L-carnitine did not influence the weight gain, food intake and food efficiency ratio among the experimental groups, but had an effect of lowering the serum total lipid and triglyceride significantly in both groups which were supplemented with L-carnitine. The effect of lowering of sew total cholesterol with the supplementation of L-carnitine in beeftallow group(BTC) only. The effect of lowering of liver total cholesterol with the supplementation of L-carnitine in perilla oil group(POC) only.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.6
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• pp.605-612
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• 2015

Three dimensional (3D) position determination and motion recognition using a 3D depth sensor camera are applied to a developed penguin-shaped robot, and its validity and closeness are investigated. The robot is equipped with an Asus Xtion Pro Live as a 3D depth camera, and a sound module. Using the skeleton information from the motion recognition data extracted from the camera, the robot is controlled so as to follow the typical three mode-reactions formed by the operator's gestures. In this study, the extraction of skeleton joint information using the 3D depth camera is introduced, and the tracking performance of the operator's motions is explained.

• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.49-56
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• 1993

This paper describes an effort of improving performances of ultrasonic ranging system using V40 microprocessor. Conventional ranging systems are somewhat inaccurate because they do not have capability of compensating changes in medium condition. The novel ranging system overcomes this disadvantage by placing a dummy sensor functioning as a standard calibrating instrument in the same medium and by providing data processing capability using V40 controller. Also data communication between V40 and personal computer via RS232C makes it possible to use the ranging system for varieties of other applications such as analysis of static and dynamic system.