• Journal of dental hygiene science
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• v.13 no.4
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• pp.403-409
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• 2013

The purpose of this study was to evaluate the correlation between caries experience, Quantitative Light-Induced Fluorescence-Digital (QLF-D) redings and new caries activity test (Cariview) results in preschool children. Fifty-seven healthy kindergarten children (male 28, female 29) were participated this study. The calibrated dentist investigated the caries experience of children and new caries activity test. Cariview samples were incubated in the activated medium at $37^{\circ}C$ for 48 hours. All QLF-D taking and readings were performed by one experienced and trained operator under identical conditions in a dental unit chair located in a darkened room. Analysis range was limited to the maxillary and mandibular anterior teeth. QLF-D redings (white spot and dental plaque) were analysed using QLF system. The dft index had a relatively high correlation with the QLF-D redings (white spot: r=0.617, simple plaque score: r=0.500) (p<0.01). Also, there was significant correlation between dft index and the Cariview score (r=0.286) (p<0.05). However, the Cariview score had no significant correlation between dt index and ft index (p>0.05). QLF-D can be evaluated objectively the initial caries lesions and dental plaque correlated with caries experience. Therefore, QLF-D will be useful to the study of caries prediction.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.556-562
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• 2007

A total of 126 crossbred weanling pigs (average body weight of $6.3{\pm}0.3$ kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, nutrient digestibility, pH of gastro-intestinal tract (GI), intestinal and fecal microflora of young piglets. Pigs were allocated to three dietary treatments based on body weight and gender in a single factorial arrangement. Treatments were control (No COS), T1 (0.2% COS during starter (6-13 kg) and 0.1% COS during grower (13-30 kg) phases, and T2 (0.4% COS during starter (6-13 kg) and 0.3% COS during grower (13-30 kg) phases, respectively. Each treatment had 3 replicates and 14 pigs were raised in each pen. COS is a low molecular weight water-soluble chitosan that can be obtained from chitin of the crab shell after deacetylation with concentrated sodium hydroxide at high temperature and then further decomposition by chitosanase enzyme in the presence of ascorbic acid. For the starter and grower periods, there were no significant differences (p>0.05) in average daily gain (ADG) and feed to gain ratio among treatments. However, during the overall period (6-30 kg), T2 showed better (p<0.05) feed to gain ratio than other treatments. A digestibility study was conducted at the end of grower phase which showed improvement (p<0.05) in DM and crude fat digestibility in T2 over the control. At 25 kg body weight, 6 pigs per treatment (2 per replicate) were sacrificed to determine the effect of diets on pH and microbial count at different sections of the GI tract. The pH of the cecal contents in pigs fed 0.1% COS was higher (p<0.05) than in the other treatments. Total anaerobic bacterial number increased from cecum to rectum in all treatments. The weekly total bacterial counts showed higher (p<0.05) in feces of pigs fed COS than that of untreated pigs at the $8^{th}$ week. The number of fecal E. coli in untreated pigs at $4^{th}$ wk was 7.35 log CFU/g compared to 6.71 and 6.54 log CFU/g in 0.1 and 0.3% COS-treated pigs, respectively. Similarly, at $8^{th}$ wk, fecal clostridium spp. were lower in pigs fed 0.3% COS (5.43 log CFU/g) than in untreated pigs (6.26 log CFU/g). In conclusion, these results indicated that chito-oligosaccharide could improve feed efficiency in young pigs and inhibited the growth of harmful bacteria.

• Nonlinear Functional Analysis and Applications
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• v.26 no.5
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• pp.1035-1044
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• 2021

Existence and uniqueness results for solutions of system of Riemann-Liouville (R-L) fractional differential equations with initial time difference are obtained. Monotone technique is developed to obtain existence and uniqueness of solutions of system of R-L fractional differential equations with initial time difference.

• Journal of Navigation and Port Research
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• v.30 no.10 s.116
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• pp.847-853
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• 2006

In this paper, we designed VCO(voltage controlled oscillator} that is composed of a dielectric resonator and a varactor diode, and the PLDRO(phase locked dielectric resonator oscillator) that is combined with the sampling phase detector and loop filter. The results at 12.05 GHz show the output power is 13.54 dBm frequency tuning range approximately +/- 7.5 MHz, and power variation over the tuning range less than 0.2 dB, respectively. The phase noise which effects on bits error rate in digital communication is obtained with -114.5 dBc/Hz at 100 kHz offset from carrier, and The second harmonic suppression is less than -41.49 dBc. These measured results are found to be more improved than those of VCO without adopting PLL, and the phase noise and power variation performance characteristics show the better performances than those of conventional PLL.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.3 s.333
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• pp.25-32
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• 2005

In this papers, we first, therefore, designed VCO(voltage controlled oscillator) that is composed of the dielectric resonator and the varactor diode, and then designed and fabricated PLDRO(phase locked dielectric resonator oscillator) that is combined with the sampling phase detector and loop filter. The measured results of the fabricated PLDRO at 12.05 [GHz] show the output power is 13.54 [dBm], frequency tuning range approximately +/- 7.5 [MHz], and Power variation over the tuning range less than 0.2 [dB], respectively. The phase noise which effects on bits error rate in digital communication is obtained with -114.5 [dBc/Hz] at 100 [KHz] offset from carrier, and The second harmonic suppression is less than -41.49 [dBc]. These measured results are found to be more improved than those of VCO without adopting PLL, and the phase noise and power variation performance characteristics show the better performances than those of conventional PLL.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.616-621
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• 2017

The objective of this study was to investigate the physicochemical properties of domestic strong wheat flour (DSWF). Three commercial DSWFs (D1, D2, and D3) were compared with imported strong wheat flour (ISWF). DSWFs had higher moisture content, crude protein content, lightness, and whiteness than ISWF. DSWFs showed lower solvent retention capacity and water absorption index than ISWF. DSWFs also showed significantly higher water solubility index than ISWF (P<0.05). Setback values by rapid visco analysis were significantly higher in D1 and D2 than in ISWF and D3, which means ISWF and D3 were better in retarding retrogradation. Differential scanning calorimetry results showed that ISWF required 6.2 J/g of energy for phase transition, whereas DSWFs needed 6.67~7.13 J/g. The farinograph results showed that ISWF had higher water absorption, longer dough stability time, and significantly higher softening of dough at 20 min than DSWF (P<0.05). Dough resistance and extensibility were higher in ISWF than in DSWFs.

• Journal of Korean Society of Water and Wastewater
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• v.13 no.2
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• pp.34-40
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• 1999

Aerobic night-soil treatment effluent containing high concentration of ammonia nitrogen was treated to remove nitrogen using Bardenpho process with Methanol addition. The objective of this study was to investigate the feasibility of complete nitrogen removal at three different HRTs such as 6.25d, 5d, and 3.75d, respectively. At each HRT, the nitrogen removal efficiencies are 92%, 99% and 97% and the required amount of methanol are 3.05gMeOH/gN, 2.75gMeOH/gN, and 3.38gMeOH/gN, respectively. Specific nitrification rates are decreased proportional to HRT and are $0.022gNH_4^+-N/g\;MLVSS{\cdot}day$, $0.0332gNH_4^+-N/g\;MLVSS{\cdot}day$ and $0.051gNH_4^+-N/g\;MLVSS{\cdot}day$ and specific denitification rate are decreased proportional to HRT and are $0.0210g\;N/gMLVSS{\cdot}day$, $0.0330g\;N/gMLVSS{\cdot}day$ and $0.0525g\;N/gMLVSS{\cdot}day$, respectively.

• Archives of Metallurgy and Materials
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• v.65 no.3
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• pp.1029-1033
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• 2020

In this study, we investigated the effect of Fe addition (0, 0.25, 0.50 and 0.75 wt.%) on the microstructure, mechanical properties and electrical conductivity of as-cast and as-extruded Al-RE alloys. As the Fe element increased by 0 and 0.75wt.%, the phase fraction increased to 5.05, 5.76, 7.14 and 7.38 %. The increased intermetallic compound increased the driving force for recrystallization and grain refinement. The electrical conductivity of Al-1.0 wt.%RE alloy with Fe addition decreased to 60.29, 60.15, 59.58 and 59.13 %IACS. With an increase in the Fe content from 0 to 0.75 wt.% the ultimate tensile strength (UTS) of the alloy increased from 74.3 to 77.5 MPa. As the mechanical properties increase compared to the reduction of the electrical conductivity due to Fe element addition, it is considered to be suitable for fields requiring high electrical conductivity and strength.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.13.1-13.9
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• 2021

Objectives: This study aimed to evaluate and compare the efficacy of the S1 reciprocating system and the D-Race retreatment rotary system for filling material removal and the apical extrusion of debris. Materials and Methods: Sixty-four freshly extracted maxillary canines were shaped with size 10 and size 15 K-files, instrumented using ProTaper Gold under irrigation with 2.5% sodium hypochlorite (NaOCl), obturated according to the principle of thermo-mechanical condensation with gutta-percha and zinc oxide eugenol sealer, and allowed to set for 3 weeks at 37℃. Subsequently, the teeth were divided into a control group (n = 4), the D-Race rotary instrument group (n = 30), and the S1 reciprocating instrument group (n = 30). After classical retreatment, the canals were subjected to a complementary approach with the XP-Endo Shaper. Desocclusol was used as a solvent, and irrigation with 2.5% NaOCl was performed. Each group was divided into subgroups according to the timing of radiographic readings. The images were imported into a software program to measure the remaining filling material, the apical extrusion, and the root canal space. The data were statistically analyzed using the Z-test and JASP graphics software. Results: No significant differences were found between the D-Race and S1 groups for primary retreatment; however, using a complementary cleaning method increased the removal of remnant filling (p < 0.05). Conclusions: Classical removal of canal filling material may not be sufficient for root canal disinfection, although a complementary finishing approach improved the results. Nevertheless, all systems left some debris and caused apical extrusion.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1445-1449
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• 2000

A total of one hundred twenty pigs ($L{\times}Y{\times}D$, $50{\pm}0.78kg$) were employed for a 7-week feeding trial to determine the effect of inclusion levels of vitamin and mineral (VTM) premixes on growth performance, nutrient digestibility and pork stability in finishing pigs. Treatments were 100% (Control), 150%, 200%, and 250% of NRC (1998) requirements. Increasing dietary VTM premixes in finishing pigs had a linear (p<0.05) effect on ADG. It also had a linear effect (p<0.05) on the digestibility of calcium and a linear and quadratic effect (p<0.05) on the digestibility of phosphorus. As dietary VTM levels were increased from 100 to 250% NRC (1998), TBARS values of pork samples were linearly (p<0.05) lowered when stored at $1^{\circ}C$ for 2 or 3 weeks. There was also a trend reducing POV of pig meat as dietary VTM level was increased. In conclusion, it would appear that inclusion of VTM premixes at the level of 200-250% of NRC (1998) requirements gave positive effects on growth performance and pork stability in finishing pigs.