• Corrosion Science and Technology
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• v.20 no.4
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• pp.196-203
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• 2021

To improve corrosion resistance and reduce the hydrogen uptake of 22MnB5, up to 5% Mg was added to the AlSi coating of 22MnB5. After hot-stamping and electrocoating were done on the metallic-coated specimen, the surface characteristics of the steel, hydrogen uptake content, and corrosion resistance were examined by transmittance electron microscopy, thermal desorption spectrometry, cyclic corrosion testing, and electrochemical impedance spectroscopy. Mg was investigated as MgO on the surface layer after hot-stamping while it existed as Mg₂Si before hot-stamping. The total hydrogen content of 22MnB5 was decreased along with the Mg content. However, there was no difference at 0.2 wt% or more. When a small amount of Mg was added, the coating corrosion resistance was decreased, but when it was added at around 1.0 wt%, the greatest corrosion resistance increase was seen. However, when 3 wt% or more was added excessively, the corrosion resistance was decreased. MgO on the surface was considered to suppress H uptake by the AlSi melting solution and increase the barrier effect of the coating.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.1
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• pp.41-47
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• 2021

Background: This study was designed to compare the efficacy of DentalVibe against 2% lidocaine gel in reducing pain during the administration of local anesthetic injection in the adult population. Methods: This was a split-mouth open-label, randomized, controlled clinical study conducted in the Department of Oral and Maxillofacial Surgery of a dental institute. Fifty patients who were scheduled for bilateral dental extractions requiring an inferior alveolar nerve block were enrolled in the study. Site A (n = 50) was coated with 2% lidocaine gel followed by a local anesthetic injection, and DentalVibe with local anesthetic injection was used for Site B (n = 50). The primary outcome was pain, which was recorded immediately after the administration of anesthetic injection using the Visual Analogue Scale [VAS 0 - 10]. Results: The VAS pain scores ranged from 4 to 10 for site A and 0 to 6 for site B. Comparison between the two sites showed a statistically significant difference [Mann-Whitney U test value = 51.50, P < 0.001] favoring site B. Conclusion: This study showed that DentalVibe reduces pain during injection of local anesthesia compared to topical anesthetic gel.

• The Journal of Korean Academy of Sensory Integration
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• v.5 no.1
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• pp.31-40
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• 2007

Objective: The purpose of this study was to get the cognitive reaction time according to the intensity of auditory stimuli in older people and to differentiate the cognitive reaction time between older people and adults. Method: 49 subjects consisted of 32 older people and 17 adults. Cognitive reaction time was assessed with Simple Auditory Reaction of Foundation I in PSS CogReHab. Analysis of the data was done by using independent t-test. Results: The results were as follows: 1. There was a significant difference of the mean of cognitive reaction time to the intensity of auditory stimuli. 2. There was no significant difference from older people regardless of sexual distinction in mean of cognitive reaction time. However, there was a significant difference of the mean of cognitive reaction time in adults. 3. There was a significant difference between older people who got a job or not in 90 dB of auditory stimuli. 4. The mean of cognitive reaction time to the intensity of auditory stimuli in older people was slower than adults. There was a significant difference of the mean of cognitive reaction time between older people and adults in 70 dB of auditory stimuli. 5. The mean of cognitive reaction time to the intensity of auditory stimuli in older people did not have the significant difference in scholastic ability. Conclusions: The results of the study showed slowing of the cognitive reaction time in auditory stimuli to aging in older people. Therefore, applying silver industry and development of equipment for older people may maintain independent life.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.3
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• pp.261-268
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• 2016

In this paper, dual-polarized monopulse cassegrain antenna for W-band millimeter-wave seeker was proposed and the performances were verified by the measured results of the fabricated antenna. Dual-polarized monopulse Cassegrain antenna consists of main/subreflector, dual-polarized feed horn and monopulse comparator. The proposed feed horn has $2{\times}2$ array square waveguide feeding structure to make monopulse signals and it was designed using 90 degree rotational symmetric structure to receive dual-polarized signals. At the sum and difference channel, the measured vertical and horizontal polarization radiation pattern were similar. Measurement gains are 35.1 dBi for v-pol. and 35.6 dBi for h-pol. at the center frequency with 0.5dBi difference between each polarization and the side lobe level is below -21.6 dB.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.4
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• pp.279-285
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• 2021

Objectives: Wound healing is an integral part of any surgical procedure. Appropriate wound closure is critical to any successful surgical procedure, especially intraoral procedures. Various factors aid in wound healing, both pharmacological and non-pharmacological. Dehydrated human amniotic/chorionic membrane (dHACM) is an emerging bioinert material that contains anti-inflammatory properties, angiogenetic properties, osteogenic potential, and various growth factors. The purpose of this study was to evaluate the efficacy of wound healing properties of dHACM in bilateral alveoloplasty patients. Materials and Methods: A prospective split-mouth study was conducted on 10 patients. Site A received sutures with dHACM and site B was sutured without dHACM. Wound healing was assessed with the Landry, Turnbull, and Howley Index. Results: Sites A and site B were compared. A P<0.05 and a test value of 22 was obtained, indicating a statistical difference between the two sites. Conclusion: Our study showed better healing with dHACM than without.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.265-272
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• 2021

A total of fourteen primiparous sows' (Landrace × Yorkshire) were used to determine the effects of two patterns of feed intake during early gestation on the growth performance and litter characteristics in sows. Daily feed intake from day 5 to 112 of gestation for parity 1 sows was 2.2 kg·d^-1 of feed offered with the exception of seven sows who were offered 3.2 kg·d^-1 from day 90 to 108 of gestation (TRT A) or 2.5 kg·d^-1 (d 5 - 60) and 2 kg·d^-1 (d 60 - 90) of feed with the exception of seven sows who were offered 3.5 kg·d^-1 from day 90 to 108 of gestation (TRT B). The different feed intake patterns in early gestation did not have a significant effect on body weight, backfat thickness, or body condition score during, before, and after farrowing (p > 0.05) respectively. However, initial to d 60, backfat thickness difference was significantly improved by TRT B patterns of feed intake during early gestation. In addition, during the overall experiment, average daily feed intake was significantly enhanced for sows in the dietary TRT B group feed intake pattern (p = 0.0001). The fecal score during day 90 was significantly reduced (p = 0.0132) in sows fed with TRT B feed intake pattern. Litter size, litter survival rate, and initial weight showed no significant differences with different feed efficiency of gestating sows. In summary, the results indicate that the 2.5 kg·d^-1 gestation intake pattern allowed gestating sows to obtain optimal performance.

• Restorative Dentistry and Endodontics
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• v.39 no.4
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• pp.276-281
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• 2014

Objectives: The purpose of this study was to compare the cutting efficiency of a newly developed microprojection tip and a diamond-coated tip under two different engine powers. Materials and Methods: The apical 3 mm of each root was resected, and root-end preparation was performed with upward and downward pressure using one of the ultrasonic tips, KIS-1D (Obtura Spartan) or JT-5B (B&L Biotech Ltd.). The ultrasonic engine was set to power-1 or -4. Forty teeth were randomly divided into four groups: K1 (KIS-1D / Power-1), J1 (JT-5B / Power-1), K4 (KIS-1D / Power-4), and J4 (JT-5B / Power-4). The total time required for root-end preparation was recorded. All teeth were resected and the apical parts were evaluated for the number and length of cracks using a confocal scanning micrscope. The size of the root-end cavity and the width of the remaining dentin were recorded. The data were statistically analyzed using two-way analysis of variance and a Mann-Whitney test. Results: There was no significant difference in the time required between the instrument groups, but the power-4 groups showed reduced preparation time for both instrument groups (p < 0.05). The K4 and J4 groups with a power-4 showed a significantly higher crack formation and a longer crack irrespective of the instruments. There was no significant difference in the remaining dentin thickness or any of the parameters after preparation. Conclusions: Ultrasonic tips with microprojections would be an option to substitute for the conventional ultrasonic tips with a diamond coating with the same clinical efficiency.

• Journal of the Korea Knowledge Information Technology Society
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• v.12 no.4
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• pp.539-550
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• 2017

In this paper, we designed, fabricated and tested an UHF band cylindrical dipole array antenna. In the proposed antenna, cylindrical dipoles were vertically arranged in four stages. A parallel structure feeding circuit was installed inside the cylindrical dipole and mounted so as to be broadband matching. The feeding circuit was installed at the center of the cylindrical dipole to optimize the gain flatness characteristic of the azimuth direction omnidirectional radiation pattern. Minimizing the difference between the signals branched from the feeding circuit and realizing the symmetry of the radiation pattern. The required specifications are more than 11.2% bandwidth in UHF band, above 6dBi antenna gain, standing wave ratio of 2:1 or less, less than ${\pm}1dB$ gain flatness in azimuth radiation pattern, more than 13 degrees in elevation radiation pattern of 3dB beamwidth. We confirmed the possibility of implementation through M&S and verified the result of M&S through production and testing. The test results are 11.2% bandwidth in the UHF band, 6.30 to 8.31 dBi gain, 1.53:1 standing wave ratio or less, within ${\pm}0.2dB$ gain flatness in the azimuth radiation pattern, elevation radiation pattern of 3dB beam width was 15.62 to 15.84 degrees. The test result meets all requirements specifications.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.2
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• pp.107-114
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• 1988

Six steers of each breed type, Hereford ($H{\times}H$), Brahman ($B{\times}B$) and Brahman $\times$ Hereford ($B{\times}H$) were ranked on liveweight and allocated to three treatments, basal hay diet (Basal), Basal plus 1 kg/head/day of cottonseed meal (Basal + CSM) and Basal plus 1 kg/head/day of formaldehyde-treated sunflower meal, $Norpro^{(R)}$ (Basal + NPO). The hay was made from a pasture based predominantly on carpet grass (Axonopus affinus) growing in subtropical New South Wales, and had an estimated organic matter digestibility of 52% and a nitrogen (N) content of 7.8 g/kg dry matter (DM). The steers were accustomed to the Basal diet over 15 days and supplements offered over 42 days. Intake of the basal hay diet by steers was not increased by supplementation. When intakes were adjusted for differences between breed types in liveweight the $B{\times}H$ steers ate 25% (P<0.01) more hay than $H{\times}H$ steers (6.3 V 5.0 kg/head/d) and $B{\times}B$ steers ate 8% less hay than $H{\times}H$ steers. Supplementation significantly (P<0.01) increased liveweight gain during the experiment, being ($g/head/d\;{\pm}\;s.e.d.$) 290, 770 and $795{\pm}118$ respectively for Basal, Basal + NPO and Basal + CSM. There was no difference between supplements in the liveweight gain of steers nor between steers of different genotypes. However, there was a significant interaction (P<0.01) between breeds and treatments such that $B{\times}B$ steers gained most on the basal diet but least of the breed types when supplemented. The estimated non-degradeable fraction of N in the protein meals was 58.5 and 44.5%, respectively for NPO and CSM. Both meals increased (P<0.01) plasma urea N and rumen ammonia N concentrations.

• Journal of applied mathematics & informatics
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• v.34 no.5_6
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• pp.369-382
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• 2016

In this paper, we investigate the global behavior of the solutions of the difference equation $x_{n+1}=\frac{A+Bx_{n-2k-1}}{C+D\prod_{i=l}^{k}x_{n-2i}^{m_i}}$, n=0, 1, ..., with non-negative initial conditions, the parameters A, B are non-negative real numbers, C, D are positive real numbers, k, l are fixed non-negative integers such that l ≤ k, and m_i, i=l, k are positive integers.