• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.29-33
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• 2020

Despite the same system architecture and operation principle, Advanced Metering Infrastructure (AMI) and Internet of Things (IoT) are recognized as a heterogeneous system. This is due to the different object modeling and communication protocols used in smart meters and sensors. However, data interworking between AMI and IoT is expected to be inevitable in the future. In this paper, we propose Device Language Message Specification (DLMS) to Lightweight Machine to Machine (LwM2M) conversion model. The proposed interworking model can reduce the packet size by 46.5% compared to that of the encapsulation method.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.208-208
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• 2002

Relationship between chlorophyll a in the East China Sea and spectral bands (412, 443,490, (510), 555, (676,765) in) of OSMI (Ocean Scanning Multi-Spectral Imager) including the profile multi-spectral radiometer (PRR-800) was studied. The values of remote sensing reflectance (Rrs) at the bands corresponding to the field chlorophyll a in α in the East China Sea were much higher than those in clear waters off California, USA. In case of the particle absorptions related to the chlorophyll a concentration at the spectral bands (440, 670 nm) were much higher in the East China Sea than the ones in the clean waters off California. The normalized water leaving radiances (nLw) at 412, 443, 490, 555 m of OSMI and field chlorophyll a in the East China Sea were correlated each other. According to the results, the relationship between field chlorophyll a and nLw 410 m in OSMI bands was the lowest, whereas that between the field chlorophyll a and nLw 555 nm in the bands was the highest. Reciprocal action between the field chlorophyll a and the band ratio of the OSMI bands (nLw410/nLw555, nLw443/nLw555, nLw490/nLw555) was also studied. Correlation between the chlorophyll a and the band ratio (nLw490/nLw555) was highest in the OSMI bands. Relationship between the chlorophyll a and the ratio (nLw443/nLw555) was higher than one in the nLw410/nLw555. The difference in the estimated chlorophyll α (mg/m3) between OSMI and SeaWiFS (Sea Viewing Wide Field-of-View Sensor) at the special observing stations in the northern eastern sea of Jeju Island in february 25, 2002 was about less than 0.3 mg/m3 within 3 hours. It is suggested that OC2 (ocean color chlorophyll 2 algorithm) be used to get much better estimation of chlorophyll α from OSMI than the ones from the updated algorithms as OC4.

• Korean Journal of Remote Sensing
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• v.18 no.4
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• pp.187-199
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• 2002

Correlation between chlorophyll a in the East China Sea and spectral bands (412, 443, 490, (510), 555, (676, 765)nm) of Ocean Scanning Multi-Spectral Imager (OSMI) including the profile multi-spectral radiometer (PRR-800) was studied. The values of remote sensing reflectance (Rrs) at the bands corresponding to the field chlorophyll $\alpha$ in the East China Sea were much higher than those in clear waters off California, USA. In case of the particle absorptions related to the chlorophyll a concentration at the spectral bands (440, 670nm) were much higher in the East China Sea than the ones in the clean waters off California. The normalized water leaving radiances (nLw) at 412, 443, 490, 555 nm of OSMI and the field chlorophyll a in the East China Sea were correlated each other. According to the results, the relationship between field chlorophyll $\alpha$ and nLw 410 nm in OSMI bands was the lowest, whereas that between field chlorophyll a and nLw 555 nm in the bands was the highest. Reciprocal action between the field chlorophyll a and the band ratio of the OSMI bands (nLw410/nLw555, nLw443/nLw555, nLw490/nLw555) was also studied. Relationship between the chlorophyll $\alpha$ and the band ratio (nLw490/nLw555) was highest in the OSMI bands. Relationship between the chlorophyll $\alpha$ and the ratio (nLw490/nLw555) was higher than one in the nLw410/nLw555. The difference in the estimated chlorophyll $\alpha$ (mg/m$^3$) between OSMI and SeaWiFS (Sea Viewing Wide Field-of-View Sensor) at the special observing stations in the northern eastern sea of Jeju Island in February 25, 2002 was about less than 0.3 mg/m$^3$ within 3 hours. It is suggested that OC2 (ocean color chlorophyll 2 algorithm) be used to get much better estimation of chlorophyll $\alpha$ from OSMI than the ones from the updated algorithms as OC4.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.3
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• pp.199-205
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• 2015

Organic wastes such as food waste (FW), livestock wastewater (LW), and sewage sludge (SWS) can produce hydrogen ($H_2$) by anaerobic acid fermentation. Expecially, FW which has high carbohydrate content produces $H_2$ and short chain fatty acids by indigenous $H_2$ producing microorganisms without adding inoculum, however $H_2$ production rate (HPR) and yield have to be improved to use a commercially available technology. In this study, LW was mixed to FW in different ratios (on chemical oxygen demand (COD) basis) as an auxiliary substrate. The mixture of FW and LW was pretreated at pH 2 using 6 N HCl for 12 h and then fermented at $37^{\circ}C$ for 28 h. HPR of FW, 254 mL $H_2/L/h$, was increased with the addition of LW, however, mixing ratio of LW to FW was reversely related to HPR, exhibiting HPR of 737, 733, 599, and 389 mL $H_2/L/h$ at the ratio of FW:LW=10:1, 10:2, 10:3, and 10:4 on COD basis, respectively. Maximum HPR and $H_2$ production yield of 737 $H_2/L/h$ and 1.74 mol $H_2/mol$ hexoseadded were obtained respectively at the ratio of FW:LW=10:1. Butyrate was the main organic acid produced and propionate was not detected throughout the experiment.

• Journal of Adhesion and Interface
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• v.2 no.3
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• pp.1-8
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• 2001

Epoxy composites filled with natural zeolite was prepared to investigate the effects of silane coupling agent, ${\gamma}$-APS (${\gamma}$-aminopropyltriethoxysilane)on the surface free energy, tensile properties and interfacial morphology. The value of Lifshitz-van der Waals component, ${\gamma}{\frac{LW}{SV}}$ for polar was $19.22mJ/m^2$ and increased, while that of Lewis acid-base component, ${\gamma}{\frac{AB}{SV}}$ for polar was $15.27mJ/m^2$ and decreased with the increasing content of ${\gamma}$-APS treatment. It is due that the surface of the zeolite is more coated by hydrophobic of alkyl group than hydrophilic amine or hydroxyl group. The tensile strength and Young's modulus of epoxy system were improved by the treatment with ${\gamma}$-APS due to the strong interface bonding, which was confirmed by SEM.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.380-384
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• 2003

Optimal extraction, separation and capillary rinsing conditions for capillary electrophoresis (CE) were established to discriminate the geographical origin of ligusticum root (Ligusticum wallichii) using 113 samples (domestic sample n = 62, foreign sample n = 51). Ligusticum root was extracted with 30% ethanol and separated on a uncoated fused-silica $(50\;{\mu}m{\times}27\;cm)$ capillary. Conditions for optimal analysis include: temperature, $40^{\circ}C$; voltage, 10 kV; and pressure injection time, domestic and foreign samples were 5 sec and 2 sec, respectively. The optimal separation buffer was 0.1 M phosphate buffer (pH 2.5) containing 15 mM iminodiacetic acid with 40% methanol. Under the optimal conditions established for CE, the ratio of specific peak area (peak LW-1) to other peak area (peak LW-5) was effective in discrimination geographical origin of ligusticum root. The mean accuracy for correct discrimination of geographical origin of domestic and foreign ligusticum roots were 65% and 63%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.1
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• pp.83-88
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• 1995

An experiment was conducted to study the comparative performance of cattle fed young or mature guinea grass (Panicum maximum Jacq. ecotype A) and urea supplemented rice straw. Evaluation was based on intake and digestibility parameters. Twelve crossbred bulls calves weighing $90{\pm}15$ kg were offered young (4 weeks regrowth) or mature (9 weeks regrowth) grass in the long or chopped (10-15 cm) form, and rice straw supplemented with urea. The diets were offered 30-60% in excess of voluntary intake, and the experiment consisted of two periods. The crude protein content of the young grass, mature grass and the straw offered were 12.2, 5.4 and 7.7%, respectively, and the refusal was 10.1, 3.9 and 7.0%, respectively. The organic matter digestibility of the young grass (69%) was significantly higher than the mature grass (62.5%) and straw (55.8%) diets. The organic matter intake (kg/100 kg LW/day) of the unchopped and chopped grass diets were 2.6 and 3.3 respectively, and these values were significantly higher (p < 0.01) than the young grass (2.3) and straw (2.1) diets. The digestible organic matter intake (DOMI) of the mature grass diet offered in the chopped form (2.1 kg/100 kg LW/day) was significantly higher (p < 0.01) than the other three diets. The DOMI of the young and mature grass offered in the long form was similar (1.6 kg/100 kg LW/day), but were significantly better (p < 0.01) than the urea supplemented straw diet.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1143-1150
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• 2008

An experiment was conducted in Vietnam to test the hypothesis that supplementation with cassava powder up to 2% of live weight (LW)/d (DM basis) would linearly increase digestible organic matter intake and LW gain of Laisind cattle. There were five treatments: a basal diet of elephant grass fed at 1.25% of LW and rice straw fed ad libitum or this diet supplemented with cassava powder, containing 2% urea, at about 0.3, 0.7, 1.3 or 2.0% LW. The cattle fed cassava powder at about 2.0% LW did not consume all of the supplement, with actual intake similar to the 1.3% LW treatment. Organic matter, digestible organic matter and digestible energy intakes increased (p<0.001) curvilinearly with increased consumption of cassava powder. Rice straw intake declined curvilinearly with increasing intake of cassava powder (p<0.001), and there was a small linear decline (p = 0.01) in grass intake. The substitution rate of cassava powder for forage was between 0.5 and 0.7 kg DM reduction in forage intake per kg DM supplement consumed, with no difference between treatments. Apparent digestibility of organic matter increased (p<0.001) in a curvilinear manner, while digestibility of neutral detergent fibre declined (p<0.001) in a curvilinear manner with increased consumption of cassava powder. Live weight gain increased (p<0.01) linearly with increased consumption of supplement. It was concluded that the amount of cassava powder fed should be limited to between 0.7 and 1.0% LW.

• Resources Recycling
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• v.17 no.1
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• pp.20-28
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• 2008

Leather waste discharged from Shinpyung Changrim Industrial Complex contained 46.3 percent of carbon, and weight loss of leather waste about 50 percent was observed at $500^{\circ}C$ by thermogravimetric analysis. Chemically activated carbon [LW4AC] was made at activation temperature of $800^{\circ}C$ during 30 minutes in electric furnace. Iodine value and decoloration of methylene blue was 968 mg/g and 158 mL/g, respectively. We found that pore volume was more developed according to the increase in the ratio of $K_2CO_3/LW$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.198-200
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• 2022

In this paper, we are going to explain the development of a platform that can integrate and manage various sensors and data by applying IoT standard technology to a smart city where various services exist. The structure was designed to integrate and manage various data through platform development and process the collected data according to the service. By designing a platform based on the LwM2M standard technology, it is possible to provide a function that can accommodate various devices.