• Animal Bioscience
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• v.34 no.6
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• pp.1029-1037
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• 2021

Objective: This study was conducted to investigate effects of antifungal substance and carboxylesterase-producing inoculant on fermentation indices and rumen degradation kinetics of whole crop rice (WCR) silage ensiled at different dry matter (DM) contents. Methods: Dual-purpose inoculants, Lactobacillus brevis 5M2 and Lactobacillus buchneri 6M1, confirmed both activities of antifungal and carboxylesterase in the previous study. The WCR at mature stage was chopped, and then wilted to obtain three different DM contents consisting of 35.4%, 43.6%, and 51.5%. All WCR forages were applied distilled water (CON) or mixed inoculants with 1:1 ratio at 1×105 colony forming unit/g (INO), and ensiled into 20 L mini silo (5 kg) in quadruplicates for 108 d. Results: The INO silages had lower lactate (p<0.001) and butyrate (p = 0.022) with higher acetate (p<0.001) and propionate (p<0.001) than those of CON silages. Ammonia-N (p<0.001), lactate (tendency; p = 0.068), acetate (p = 0.030), and butyrate (p<0.001) concentrations of INO silages decreased linearly with increasing DM content of WCR forage. The INO silages presented higher lactic acid bacteria (p<0.001) with lower molds (p<0.001) than those of CON silages. Yeasts (p = 0.042) and molds (p = 0.046) of WCR silages decreased linearly with increasing DM content of WCR forage. In the rumen, INO silages had higher the total degradable fraction (p<0.001), total volatile fatty acid (tendency; p = 0.097), and acetate (p = 0.007), but lower the fractional degradation rate (p = 0.011) and propionate (p<0.001) than those of CON silage. The total degradable fraction (p<0.001), total volatile fatty acid (p = 0.001), iso-butyrate (p = 0.036), and valerate (p = 0.008) decreased linearly with increasing DM content of WCR forage, while the lag phase (p<0.001) was increased linearly. Conclusion: This study concluded that application of dual-purpose inoculants on WCR silage confirmed antifungal and carboxylesterase activities by inhibiting mold and improving rumen digestibility, while increase of wilting times decreased organic acids production and rumen digestibility.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.1
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• pp.54-62
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• 2015

Small scale paint overspray booths are being operated nationwidely, for repair of passenger car body parts. paint aerosols are emitted from the paint overspray booth in operations. In paint overspray booth operations without ventilation system and air pollutants collection unit, it may land on nearby equipment. In this study a removal of sticky paint aerosol for application of the small-scale overspray paint booth. it's cause the surface of filter bag from generated sticky paint aerosol. To remove adhesion of paint aerosol the agglomerating agents are injected and mixed with sticky paint aerosols prior to reach the filter bag. The paint spray rate was set as $10{\pm}5g/min$ from air-atomized spray guns in the spray booth, injection rate of agglomerating was $10{\pm}5g/min$ in the mixing chamber. The filtration velocity including air pollutants varied from 0.2 m/min to 0.4 m/min. Bag cleaning air pressure was set as $5.0kg_f/min$ for detaching dust cake from surface of filter bag. Bag cleaning interval at the filtration velocity of 0.2 m/min was around 3 times longer than that of the 0.4 m/min. The residual pressure drop maintained highest value at the highest filtration velocity. Fractional efficiency of 99.952%~99.971% was possible to maintain for the particle size of 2.5 microns. Total collection efficiency at the filtration velocity of 0.2 m/min was 99.42%. During this study we could confirm high collection efficiency and long cleaning intervals for the test with filtration velocity of 0.2 m/min indicating an optimal value for the given dimensions of the test unit and test operating conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.355-365
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• 2004

Two experiments were conducted to determine the effect of alkaline hydrogen peroxide (AHP) treatment (1% NaOH+1.5% $H_2O_2$; 1 AHPMS, 2% NaOH+1.5% $H_2O_2$; 2AHPMS) on rate and extent of degradation of mustard straw (MS) in sacco in sheep, and its in vivo digestion and ruminal fermentation characteristics when fed to sheep with concentrate (200 g per sheep daily). The treatment of straw with 1 and 2% AHP increased its sodium content by 148 and 296% to that of untreated straw (UMS). There was significant decrease in NDF and hemicellulose contents of AHP treated straw and increase in cellulose and lignin contents. Phenolic acids like ferrulic, $\rho$-coumaric and o-coumaric significantly (p<0.001) reduced by AHP treatment of mustard straw. In first experiment the in sacco degradation of DM, OM and NDF was significantly (p<0.01) greater for 2 AHPMS than for UMS at all incubation periods. The disappearance of nutrient from 1 AHPMS and 2 AHPMS treated straws continue to increase up to 96 h whereas in UMS the peak disappearance was found at 48 h. By using the equation {(y=a+b) ($1-e^{-ct}$)} the degradation rates (c) for DM, OM, and NDF were significantly higher for UMS than AHP treated straws. Level of alkali (1 and 2%) had significant effect on degradation characteristics (a, b, c and $P_{0.05}$) of DM and NDF fraction of MS. However, the effect was not pronounced on OM fraction of MS. In feeding experiment, the intake of nutrients for DM, OM, cell wall constituents and energy was higher on 2 AHPMS, whereas no effect on the digestibility of these nutrients was observed. The apparent nitrogen retention was higher (p<0.05) both in 1 and 2 AHPMS groups. Water intake by animals was significantly increased due to AHP treated mustard straw feeding. Rumen liquor pH was higher in 2 AHPMS fed animals. The $NH_3-N$ of rumen liquor was not affected by feeding of AHP treated MS based diets. Total VFA concentration was significantly (p<0.01) higher in UMS fed group. The fractional out flow rate of DM was higher (p<0.05) in animals fed on 2 AHPMS diets compared to UMS and lAHPMS fed groups. The population of large holotrichs was higher (p<0.05) on AHP treated MS fed diets compared to UMS. The study indicated that treatment of mustard straw with AHP changed its chemical composition towards a better feed. The nutritive value of 2% AHP treated mustard straw was better in terms of dry matter intake and apparent nitrogen retention. The higher in sacco DM, OM and NDF disappearance however, was not confirmed by in vivo data in this study.

• ETRI Journal
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• v.40 no.2
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• pp.167-179
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• 2018

This paper proposes an IEEE 802.15.4m compliant TV white-space orthogonal frequency-division multiplexing (TVWS)-(OFDM) radio frequency (RF) transceiver that can be adopted in advanced metering infrastructures, universal remote controllers, smart factories, consumer electronics, and other areas. The proposed TVWS-OFDM RF transceiver consists of a receiver, a transmitter, a 25% duty-cycle local oscillator generator, and a delta-sigma fractional-N phase-locked loop. In the TV band from 470 MHz to 698 MHz, the highly linear RF transmitter protects the occupied TV signals, and the high-Q filtering RF receiver is tolerable to in-band interferers as strong as -20 dBm at a 3-MHz offset. The proposed TVWS-OFDM RF transceiver is fabricated using a $0.13-{\mu}m$ CMOS process, and consumes 47 mA in the Tx mode and 35 mA in the Rx mode. The fabricated chip shows a Tx average power of 0 dBm with an error-vector-magnitude of < 3%, and a sensitivity level of -103 dBm with a packet-error-rate of < 3%. Using the implemented TVWS-OFDM modules, a public demonstration of electricity metering was successfully carried out.

• Journal of Navigation and Port Research
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• v.35 no.1
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• pp.51-56
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• 2011

In this paper, we presents an algorithm which restores lost data or increases resolution of a DTM(Digital terrain model) using fractal theory. Terrain information(fractal dimension and standard deviation) around the patch to be restored is extracted and then with this information and original data, the elevations of cells are interpolated using the random midpoint displacement method. The results of the proposed algorithm are compared with those of the bilinear and bicubic methods on a fractal terrain map.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.6
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• pp.2686-2708
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• 2020

This paper investigates the energy efficiency of energy harvesting (EH) bidirectional cooperative sensor networks, in which the considered system model enables the uplink information transmission from the sensor (SN) to access point (AP) and the energy supply for the amplify-and-forward (AF) relay and SN using power-splitting (PS) or time-switching (TS) protocol. Considering the minimum EH activation constraint and quality of service (QoS) requirement, energy efficiency is maximized by jointly optimizing the resource division ratio and transmission power. To cope with the non-convexity of the optimizations, we propose the low complexity iterative algorithm based on fractional programming and alternative search method (FAS). The key idea of the proposed algorithm first transforms the objective function into the parameterized polynomial subtractive form. Then we decompose the optimization into two convex sub-problems, which can be solved by conventional convex programming. Simulation results validate that the proposed schemes have better output performance and the iterative algorithm has a fast convergence rate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.219-222
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• 2003

In this paper, we designed a Ku-band BPF(Band Pass Filter) by microstrip line that most usually used a microwave device design and fabrication. Here a substrate of designed BPF were silicon substrate(${\varepsilon}_r=11.8$), and metal line was copper and silver/copper structure. And a configration of BPF was used hairpin pattern. A center frequency of designed BPF was 10GHz and their FBW(Fractional Band Width) was 20%(2GHz). It presented simulated results obtained for a 10GHz filter which yields an insertion loss of 0.1dB that ripple value related chebyshev reponse. Finallt we tried to make that a 30dB attenuation frequency was 20% of center frequency.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.363-370
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• 2005

There are approximately 2,000 metallic mines which have been abandoned in Korea. Most of the mines are located in the watershed area, which is main source of drinking water for Seoul Metropolitan area. Untreated mining wastes are remained around abandoned mines in study area. These mining wastes, flowing into farmland and stream in the downstream of abandoned mines, would cause water and soil pollution. The mining waste samples from Guedo mine, Manjung mine and Joil mine recently abandoned were collected for the evaluation of the potential of water pollution by mine waste. Index of geoaccumulation($M\"{u}ller$, 1979), fractional composition and removal efficiency of some heavy metals by different concentration of HCl treatment were analyzed. Index of geoaccumulation of Cd, Pb, Zn, Cu, Ni and Cr are 6, $4{\sim}6,\;0{\sim}6,\;4{\sim}5$, 2 and 0 respectively. Index of geoaccumulation of Cd, Pb, Zn and Cu reveals the mining wastes has high pollution pottential in the area. Organic fraction of Cu, reducible fraction of Pb, residual fraction of Ni and Zn were the most abundant fraction of heavy metals in mining wastes.

• Resources Recycling
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• v.19 no.6
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• pp.27-35
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• 2010

Rare earth alloys and compounds are the raw materials for the manufacture of advanced materials. Although domestic monazite ores have been found, there are some difficulties in recovering rare earth from these ores. Rare earth ores are found in few countries and these countries put an embargo on the export of rare earth ores for the protection of their industry. We gathered some information on the hydrometallurgical and pyrometallurgical processes to recover rare earths from bastnasite, monazite, and xenotime which consist of 95% of the total rare earth ores. Since rare earth with the purity more than 6N is needed for use in advanced materials, some separation methods such as fractional crystallization, precipitation, ion exchange, and solvent extraction were introduced.

• ETRI Journal
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• v.45 no.2
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• pp.338-345
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• 2023

A filtering power divider based on air-filled substrate-integrated waveguide (AFSIW) technology is proposed in this study. The AFSIW structure is used in the proposed filtering power divider for substantially reducing the transmission losses. This structure occupies a large area because of the use of air as a dielectric instead of typical dielectric materials. A filtering power divider provides power division and frequency selectivity simultaneously in a single device. The proposed filtering power divider comprises three AFSIW cavities. The filtering function is achieved using symmetrical inductive posts. The input and output ports of the proposed circuit are realized by directly connecting coaxial lines to the AFSIW cavities. This transition from the coaxial line to the AFSIW cavity eliminates the additional transitions, such as AFSIW-SIW and SIW-conductor-backed coplanar waveguide, applied in existing AFSIW circuits. The proposed power divider with a second-order bandpass filtering response is fabricated and measured at 5.5 GHz. The measurement results show that this circuit has a minimum insertion loss of 1 dB, 3-dB fractional bandwidth of 11.2%, and return loss exceeding 11 dB.