• The Journal of the Acoustical Society of Korea
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• v.38 no.5
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• pp.534-542
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• 2019

In active SONAR, several different methods are used to detect range-Doppler information of the target. Compressive sensing based method is more accurate than conventional methods and shows superior performance. There are several compressive sensing algorithms for range-Doppler estimation of active sonar. The ability of each algorithm depends on algorithm type, mutual coherence of sensing matrix, and signal to noise ratio. In this paper, we compared and analyzed computational performance and accuracy of various compressive sensing algorithms for range-Doppler estimation of active sonar. The performance of OMP (Orthogonal Matching Pursuit), CoSaMP (Compressive Sampling Matching Pursuit), BPDN (CVX) (Basis Pursuit Denoising), LARS (Least Angle Regression) algorithms is respectively estimated for varying SNR (Signal to Noise Ratio), and mutual coherence. The optimal compressive sensing algorithm is presented according to the situation.

• Elastomers and Composites
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• v.55 no.4
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• pp.306-313
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• 2020

To investigate the reinforcing effects of functional fillers in nitrile rubber (NBR) materials, high-structure carbon black (HS45), coated calcium carbonate (C-CaCO3), silica (200MP), and multi-walled carbon nanotubes (MWCNTs) were used as functional filler, and carbon black (SRF) as a common filler were used for oil-resistant rubber. The curing and mechanical properties of HS45-, 200MP-, and MWCNT-filled NBR compounds were improved compared to those of the SRF-filled NBR compound. The reinforcing effect also increased with a decrease in the particle size of the fillers. The C-CaCO3-filled NBR compound exhibited no reinforcing effect with increasing filler concentration because of their large primary particle size (2 ㎛). The reinforcing behavior based on 100% modulus of the functional filler based NBR compounds was compared by using several predictive equation models. The reinforcing behavior of the C-CaCO3-filled NBR compound was in accordance with the Smallwood-Einstein equation whereas the 200MP- and MWCNT-filled NBR compounds fitted well with the modified Guth-Gold (m-Guth-Gold) equation. The SRF- and HS45-filled NBR compounds exhibited reinforcing behavior in accordance with the Guth-Gold and m-Guth-Gold equations, respectively, at a low filler content. However, the values of reinforcement parameter (100Mf/100Mu) of the SRF- and HS45-filled NBR compounds were higher than those determined by the predictive equation model at a high filler content. Because the chains of SRF composed of spherical filler particles are similarly changed to rod-like filler particles embedded in a rubber matrix and the reinforcement parameter rapidly increased with a high content of HS45, the higher-structured filler. The reinforcing effectiveness of the functional fillers was numerically evaluated on the basis of the effectiveness index (��SRF/��f) determined by the ratio of the volume fraction of the functional filler (��f) to that of the SRF filler (��SRF) at three unit of reinforcing parameter (100Mf/100Mu). On the basis of their effectiveness index, MWCNT-, 200MP-, and HS45-filled compounds showed higher reinforcing effectiveness of 420%, 70%, and 20% than that of SRF-filled compound, respectively whereas C-CaCO3-filled compound exhibited lower reinforcing effectiveness of -50% than that of SRF-filled compound.

• ETRI Journal
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• v.40 no.2
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• pp.207-217
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• 2018

As implementation of the in-band full duplex (IFD) transceiver becomes feasible, research interest is growing with respect to using IFD communication with cellular networks. However, the cellular network in which the IFD communication is applied inevitably suffers from an increase of the co-channel interference (CCI) due to IFD simultaneous transmission and reception. In this paper, we analyze the performance of a cellular network based on uni-directional IFD (UD-IFD) communication, wherein an IFD base station simultaneously supports downlink and uplink transmissions of half-duplex (HD) users. In addition, a multi-pair CCI cancellation (MP-CCIC) method combining CCIC and user pairing is proposed to improve the performance of the UD-IFD network. Simulation results showed that, compared to a conventional HD cellular network without using CCIC, capacity gain was not obtained in the UD-IFD cellular network. On the other hand, when applying the proposed MP-CCIC, the capacity of the UD-IFD cellular network greatly improved compared to that of an HD cellular network.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.87-94
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• 2012

We evaluated the bioavailability of a novel organic Ca supplement chelated with milk protein (CaMP) in growing rats and compared it with those of Ca carbonate and Ca citrate. Four-week-old male rats were divided into six groups (n=6/group) and fed AIN-93G-based experimental diets containing three Ca sources, Ca carbonate, Ca citrate, and CaMP at two levels, normal (0.5%, w/w) and high (1.5%, w/w), for 6 weeks. Growth, mineral contents of serum, Ca content and breaking force of femur, and Ca absorption were measured. There were no significant differences in weight gain or food intake, but food efficiency ratio (FER) of CaMP in the high Ca group was higher than those of other groups. Ca and P concentrations in serum were within normal range in all experimental rats. There was no difference in Ca content of the femur among all of the groups. Although there was no statistical significance in bone breaking force of the femur among the groups, the CaMP groups had a higher breaking force compared to other groups. Further, Ca absorption rate significantly increased in the CaMP groups (p<0.05). These results demonstrate that the CaMP supplement did not exhibit any negative effect on growth or Ca metabolism of the rats. Therefore, CaMP can be recommended as a good Ca supplement with regard to bone metabolism and Ca bioavailability.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.119-127
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• 2012

To investigate the influence of multi-probiotic, fermented ginseng byproduct and fermented sulfone on the performance, intestinal microflora and immunity of broiler, a five weeks trial was conducted with 340, 1-d-old $Ross{\times}Ross$ broiler. All broilers were divided into five different groups having 68 birds in each treatment, and they were assigned as control, antibiotic avilamycin (AB), multi-probiotic (MP), fermented sulfone (FS) and fermented ginseng byproduct (FGB). Each artificial or naturally derived probiotic was inoculated 0.1% level with the basal diet, and all diets were provided to birds for five weeks. Weight gain and feed intake were measured weekly basis, and blood, spleen and feces were collectedand used for the physiological properties of broiler chickens. All performances and cholesterol profiles were not significantly differed but numerically lower level of neutral fat and LDL was found in multi-probiotics and FGB treatments respectively. The salmonella spp and E. coli numbers in the ileum were high in control in relation to those of other treatments and were significantly decreased in antibiotics treatments (p<0.05). In addition, Lactobacillus spp. showed significantly higher proliferation in MP as compared to that of others (p<0.05). Fecal ammonia and $CO_2$ gas emission was significantly decreased in MP, FGB and FS, respectively (p<0.05), but significantly increased proliferation of spleen was determined in MP group in comparison of other treatments (p<0.05). Therefore, the results indicates that multi-probiotics would be valuable feed additives to improve the salmonella, E. coli and Lactobacillus proliferation, and manure gas emission of broiler chickens, but further study related to the production of manure gas emission of MP is necessary.

• Journal of Electrochemical Science and Technology
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• v.15 no.3
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• pp.365-372
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• 2024

As the energy density of lithium-ion batteries (LIBs) continues to increase, various separators are being developed to with the aim of improving the safety performance. Although poly(imide) (PI)-based separators are widely used, it is difficult to control their pore size and distribution, and this may further increase the risk associated. Herein, a melamine phosphonic acid (MP)-coated PI separator that can effectively control the pore structure of the substrate is suggested as a remedy. After the MP material is embedded into the PI separator with a simple one-step casting process, it effectively clogs the large pores of the PI separator, preventing the occurrence of internal short circuits during charging. It is anticipated that the MP material can also suppress rapid thermal runaway upon cycling due to its ability to reduce the internal temperature of the LIB cell caused by the desirable endothermic behavior around 300℃. According to experiments, the MP-coated PI separator not only decreases the thermal shrinkage rate better than commercial poly(ethylene) (PE) separators but also exhibits a desirable Gurley number (109.6 s/100 cc) and electrolyte uptake rate (240%), which is unique. The proposed separator is electrochemically stable in the range 0.0-5.0 V (vs. Li/Li⁺), which is the typical working potential of conventional electrode materials. In practice, the MP-coated PI separator exhibits stable cycling performance in a graphite-LiNi_0.83Co_0.10Mn_0.07O₂ full cell without an internal short circuit (retention: 90.3%).

• Analytical Science and Technology
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• v.8 no.4
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• pp.511-517
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• 1995

A cationic water soluble porphyrin (5,10,15,20-tetrakis (l-methyl-pyridinium-4-yl)porphyrin, $H_2tmpyp^{4+}$) and its metalloporphyrins (MP) were easily extracted into acetonitrile separated by addition of sodium chloride ($4mol\;dm^{-3}$) in the presence of sodium perchlorate, where M denotes $Zn^{2+}$, $Cu^{2+}$, $Co^{3+}$, $Fe^{3+}$, and $Mn^{3+}$ and $P^{2-}$ is porphyrinate ion. The extracted ion-pair complexes were completely dissociated to $[MP(ClO_4)_3]^+$, and $[MP(ClO_4)_2]^{2+}$. The extraction and the dissociation constants were determined by taking into account of the partition constant of sodium perchlorate ($K_D=1.82{\pm}0.01$). The chemical properties of the separated acetonitrile phase as $E_{T(30)}$ and $D_{II,I}$ were determined and compared with other water miscible solvents (acetone, actonitrile, 1,4-dioxane, tetrahydrofuran, 1-propanol and 2-propanol). Furthermore, a sensitive and selective method was proposed for the determination of a subnanogram amount of copper(II) in natural water samples by using the present salting-out method and the porphyrins.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.355-362
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• 2004

The purpose of this study was to herd management and control of dairy cows by milk components analysis in Gyeongsangnamdo. Milk components analysis were carried out milk yield (MY), milk fat (MF), milk protein (MP), milk urea nitrogen (MUN) and somatic cell count (SCC) but, milk solid (MS), day of non-pregnant condition (DNPC), and days of primipara (DPRI) involved in report. Dairy farms were divided high group, middle group, low group according to the standard records for milk components. Examination records were divided by farm, parity, year, season and month, the number of samples were 28,957. Feeding management practice and the prediction for the risk possibility of productive disease such as reproductive and metabolic disorders by evaluating fat, protein, solids. Determination of MY, MF, MP, MS were Milkoscan 4,000~5,000 Serier (FOSS Electric Co., Copenhagen, Denmark). Correlation coefficient of milk protein (MP) and milk solid (MS) was ascertain r=0.759. SCC was ascertain 372.8$\pm$11.34 (thousand unit) and DNPC was ascertain 155.3$\pm$5.15 (days) in seven parity.

• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.178-183
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• 2010

Purpose : The aim of this study was to identify mutations associated with macrolide resistance in Mycoplasma pneumoniae (MP) and to establish a cultural method to determine antimicrobial susceptibility. Methods : Nasopharyngeal aspirates (NPAs) were collected from 62 children diagnosed with MP pneumonia by a serologic method or polymerase chain reaction. The 23S rRNA and L4 ribosomal protein genes of MP were amplified and sequenced. To identify mutations in these 2 genes, their nucleotide sequences were compared to those of the reference strain M129. MP cultivation was carried out for 32 (28 frozen and 5 refrigerated) NPAs and M129 strain using Chanock's glucose broth and agar plate in a 5% $CO_2$ incubator at $37^{\circ}C$ and examined at 2-3 day intervals for 6 weeks. Results : Among the 62 specimens, 17 had M144V mutations in ribosomal protein L4. The A2064G mutation was observed in 1 specimen; its 23S rRNA gene was successfully sequenced. Culture for MP was successful from the M129 strain and 2 of the 5 NPAs that were refrigerated for no longer than 3 days. However, MP did not grow from the 28 NPAs that were kept frozen at $-80^{\circ}C$ since 2003. Conclusion : We found the M144V mutation of L4 protein to be common and that of domain V of 23S rRNA gene was relatively rare among MP. Studies on the prevalence of macrolide-resistant MP and the relationship between the mutations of 23S rRNA gene and ribosomal protein L4 will aid in understanding the mechanism of macrolide resistance in MP.

• Natural Product Sciences
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• v.15 no.3
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• pp.144-150
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• 2009

Gradient centrifugal partition chromatography (GCPC) method was developed and applied to isolate 3,5-dimethoxyphenanthrene-2,7-diol (DMP) and batatasin-I (BA-I) from the dichloromethane soluble extract of Dioscorea opposita. In this method, the lower phase of n-hexane-methanol-water system (HMW, 10 : 9 : 1, v/v) was used as a mobile phase A (MpA) and water was used as a mobile phase B (MpB). This gradient CPC method is comparable to that of reversed-phase HPLC method in that the stationary upper-phase of HMW (10 : 9 : 1 v/v) works as if it were reversed-phase silica gel due to its hydrophobic property, while the lower phase (MpA) and water (MpB) functioned as hydrophilic mobile phases. The initial condition of the mobile phase was 20% MpA/80% MpB and maintained for 150 min to obtain DMP (1.2 mg), and then MpA was increased up to 50% to elute BA-I (1.7 mg). The purities of DMP and BA-I were 94.1% and 98.3% with the recovery yields of 83% and 86%, respectively. Similar results were obtained by linear-gradient CPC. The CPC peak fractions were identified by comparing their retention time to those of authentic samples of DMP and BA-I and their spectroscopic data ($^1$H NMR and $^{13}$C NMR) to those of literature values.