• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.105-112
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• 2005

This study was conducted on paddy-land at Kimje, ChunBuk in Korea from Nov. 1999 to Nov. 2002. The aim of this study was to investigate the effect of pig slurry (PS) on dry matter (DM) yield, N yield and nutritive value of rye, and soil total nitrogen (TN), Phosphorus (P) and organic matter (OM) content. This experiment was consisted of 4 plot (chemical fertilizer; N: 100/100, $P_2O_5: 150,\;K_2O: 150$ kg/ha; PS $100\%$ treatment, PS $200\%$ treatment and PS $100\%$ treatment with half of CF). 1. DM yields of rye revealed that there was an increase in order; PS $100\%$ treatment with half of chemical fertilizer (CF) > PS $200\%$ treatment > full of CF treatment > PS $100\%$ treatment. 2. Crude protein (CP) content was the highest with PS $200\%$ treatment ($10.53\%$) and followed by PS $100\%$ treatment with half of CF and full of CF treatment and the lowest with PS $100\%$ treatment. 3. The contents of NDF and TDN were hardly influenced by PS and CF 4. N yields of rye revealed that there was an increase in order; PS $200\%$ treatment > PS $100\%$ treatment with half of CF > full of CF treatment > PS $100\%$ treatment. 5. The contents of TN and OM were not influenced by the application levels of PS. however, The TN content increased by the application of PS, as increasing the application period 6. P content of the soil was not affected by the application levels of PS during the experimental period.

• Resources Recycling
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• v.22 no.6
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• pp.33-40
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• 2013

Due to the environmental problem caused by plastics largely used in various fields, the importance of recycling is being emphasized. A research on material separation of ABS and PS mixed plastic waste, using a triboelectrostatic separator, was carried out for recovery the ABS. As a results of research on charging characteristic for choosing charging material, it was confirmed that ABS was optimum charging material for a tribo-charger in the material separation of ABS and PS. In the material separation using ABS charger, ABS grade of 99.5% and recovery of 92.5% were achieved at 20 kV, splitter position +2 cm from the center and 30% relative humidity. Therefore, material separation technique for recycling ABS and PS mixed plastic waste was established.

• Journal of Powder Materials
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• v.23 no.4
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• pp.276-281
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• 2016

Carbonyl iron (CI) is successfully incorporated as an additive into a polystyrene (PS) matrix via a highenergy ball milling method, under an n-hexane medium with volume fractions between 1% and 5% for electromagnetic interference shielding applications by the combination of magnetic CI and an insulating PS matrix. The morphology and the dispersion of CI are investigated by field emission scanning electron microscopy, which indicates a uniform distribution of CI in the PS matrix after 2 h of milling. The thermal behavior results indicate no significant degradation of the PS when there is a slight increase in the onset temperature with the addition of CI powder, when compared to the as-received PS pellet. After milling, there are no interactions between the CI and the PS matrix, as confirmed by Fourier transformed infrared spectroscopy. In this study, the milled CI-PS powder is extruded to make filaments, and can have potential applications in the 3-D printing industry.

• Neonatal Medicine
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• v.16 no.2
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• pp.101-109
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• 2009

Pulmonary surfactant (PS) therapy in premature infants has a remarkable impact on improving survival and outcomes in neonatal respiratory distress syndrome (RDS). Early PS therapy involves instillation of PS upon delivery of very premature infants or if there is evidence of RDS, such as an increased requirement of oxygen 2 hours after birth, especially in infants <30 weeks gestation. Early PS treatment in very premature infants results in a significant reduction in the severity of RDS, mortality, and incidence of pneumothorax, pulmonary interstitial emphysema, and bronchopulmonary dysplasia in comparison with late PS treatment. According to European and American consensus guidelines on the management of neonatal RDS, early PS instillation should be considered for infants <30 weeks gestation, infants with a birth weight <1,250 g, or if the mother has not received antepartum corticosteroids. We suggest that the Korean health insurance policy on RDS be modified so that PS can be used for better clinical outcomes of very premature infants.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.247-255
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• 1992

Polystyrene-poly(caprolactone) (PS-PCL) block copolymer was synthesized from macroazoinitiator, and its compatibilizing effect in poly(2, 6-dimethyl-1, 4-phenylene oxide) (PPO)/poly(styrene-co-acrylonitrile) (SAN, 25wt% acrylonitrile) blend was studied. PS block and PCL block in the block copolymer had shown miscibility with PPO and SAN respectively. The dissolution of SAN into PPO domain was promoted by the addition of the PS-PCL block copolymer.

• Korean Journal of Optics and Photonics
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• v.18 no.2
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• pp.162-166
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• 2007

In this paper, we propose a WDM optical true time-delay (OTTD) beam former for phased way antenna (PAA) systems. It is composed of a delay lines matrix and a multiwavelength source with discrete DFB laser diodes. The building block of a delay lines matrix is a $2\times2$ optical MEMS switch with proper fiber-optic delay line connected between cross ports. A $4\times3$ matrix using four DFB lasers has been fabricated with unit time-delay difference of 12 ps. Maximum time-delay error was measured to be -1.74 ps and +1.14 ps at a radiation angle of $46.05^{\circ}$, corresponding to error range of $-2.87^{\circ}\sim+1.88^{\circ}$. By measuring time-delays at six different RF frequencies from 5- to 10-GHz, we verified the true time-delay characteristic of our OTTD.

• Polymer(Korea)
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• v.36 no.6
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• pp.727-732
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• 2012

Baroplastic poly(butyl acrylate) (PBA)/polystyrene (PS) blends were prepared by mixing PBA and PS emulsions synthesized by cationic and anionic surfactant, respectively. Interestingly, the heterocoagulation of nanoparticles have found to be affected strongly by emulsion concentration but the blends have been prepared with almost same compositions regardless of the amount of reactants. Utilizing this method, PBA/PS/Si hybrid nano-blends were prepared successfully via electrostatic attraction forces between PBA, PS and silica nanoparticles. The hybrid nano-blend having 2 or 5 wt% of silica was then processed to a semi-transparent film at $25^{\circ}C$ under 13.8 MPa for 10 min, which showed 3.0 MPa of tensile strength and 25 MPa of elastic modulus. Therefore, the heterocoagulation technique can be used for preparing baroplastics with uniform compositions of polymer and silica nanoparticles.

• Journal of Advanced Navigation Technology
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• v.24 no.2
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• pp.115-120
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• 2020

PS-LTE, which is mentioned as a next-generation disaster network technology, is a communication technology that supports communication between terminals and group communication necessary for public safety communication based on LTE technology. Currently, Korea is establishing a PS-LTE network construction plan and installing a PS-LTE system. The world is currently making a lot of efforts to build a disaster network system using PS-LTE. However, due to the characteristics of the closed network that only the related persons can access, it can not be operated like the existing commercial network, so it is necessary to build a new network. And it is expected that many periods and costs will be required. In order to establish a disaster safety communication network efficiently, it is necessary to consider the linkage of PS-LTE network, which is newly constructed by complementing the problems such as security and access priority to existing LTE network rather than unconditional new construction.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.279-284
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• 2007

Two bacterial strains isolated from soil (Bacillus subtilis strains: PS2 and RFO41) were evaluated to determine their promoting effect on the growth of tomato seedling under axonic and pot conditions. The production of phytohormone, such as indole-3-acetic acid, indole-3-butyric acid, gibberellin and zeatin by these two strains was investigated as possible mechanisms for plant growth stimulation. Both PS2 and RFO41 were shown to produce various phytohormones, and. the production of phytohormones was stimulated by the addition of peptone-rich brain heart broth medium. In addition, these bacteria exhibited high levels of phosphatase activity, which ranged from 2.18 to $2.7\;{\mu}\;{\rho}-nitrophenol/ml/hr$. PS2 and RFO41 were applied to the pot test for growth of tomato seed with phosphate. Root and shoot lengths of germinated tomato after 15 days were 45.5% and 36.5% longer than that of control in RFO41 treated samples, respectively. Baciller sp. PS2 and RFO41 may have a potential for biofertilizer in the agriculture.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.418-428
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• 2017

In this study, the effects of pre-converted nitrite from Swiss chard powder (PS) on the color stability and shelf-life of cooked pork patties during refrigerated storage for 28 d were investigated. Nitrite was added at a concentration of approximately 120 ppm. Five treatments were formulated as follows: Control (120 ppm nitrite), T1 (2% PS), T2 (2% pre-converted nitrite from celery powder; PC), T3 (1% PS + 60 ppm nitrite), and NC (nitrite-free). The T1 and T3 samples had higher nitrosoheme pigment contents, which were associated with the redness of the samples (p<0.05). T1 resulted in the highest redness value (p<0.05). The redness and yellowness of the cooked pork patties increased with increasing PS levels. The pH of the samples subjected to all treatments decreased with progress of the storage period (p<0.05). The pH of the T1 and T3 samples treated with PS was lower (p<0.05) than that obtained with other treatments, as PS has a lower pH value. The treatments in which PS was added were most effective for reducing the level of thiobarbituric acid reactive substances (TBARS) and the residual nitrite content relative to the control. T1 resulted in the highest flavor, off-flavor, and overall acceptability scores during storage (p<0.05). The total viable bacterial count for all treatments was below 1 Log CFU/g, and E. coli and coliform bacteria were not detected during storage. Therefore, these results suggested that pre-converted nitrite from Swiss chard powder is a potential replacement for nitrite in meat products.