• 한국산학기술학회논문지
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• 제20권11호
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• pp.458-468
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• 2019

본 연구는 12주간 웨이트트레이닝에 의한 체지방 감소가 개인적인 특성과 피부두겹의 변화 등에 어떠한 영향을 미치고 있는지를 분석하여 보다 효과적인 웨이트트레이닝 전략을 제안한 연구이다. 분석결과 첫째 개인특성이 피부두겹의 변화에 유의한 영향을 미치지 않았으나 체지방 변화에는 높은 수준의 영향을 미치는 것으로 나타났다. 둘째, 피부두겹의 변화는 체지방 변화에 통계적으로 유의한 영향을 주었다. 셋째, 웨이트트레이닝에 의한 피부두겹의 변화는 남성이 여성에 비해 상대적으로 높은 변화수준을 보였다. 체지방 변화에 있어서도 남성이 여성에 비해 높은 변화를 보이는 것으로 나타났다. 본 결과를 종합하면 12주간의 웨이트트레이닝을 통해 나타난 피부두겹과 체지방의 변화는 개인특성에 의해 수준의 차이가 존재하고 있으며, 피부두겹의 변화는 체지방 변화에 높은 수준의 영향을 미치고 있음을 확인할 수 있다. 이는 본 연구의 웨이트트레이닝 프로그램은 획일적인 방법과 양으로 같은 성과를 나타내려는 노력보다는 개인특성에 맞는 웨이트트레이닝의 시간, 양, 수준을 고려한 규칙적인 웨이트트레이닝 프로그램을 실시한다면 현대인의 비만 문제를 해결하고, 건강관련 체력을 향상시키는데 보다 긍정적인 영향을 미칠 것으로 생각된다.

• 대한치과교정학회지
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• 제51권2호
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• pp.135-141
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• 2021

Objective: To assess the effects of thermoforming on aligner thickness and gap width in six aligner systems with the same nominal thickness. Methods: Six passive upper aligners of different brands were adapted to a single printed cast. Each sample was evaluated with high-resolution micro-computed tomography. To investigate aligner thickness and gap width, two-dimensional (2D) analysis was conducted assessing the effects of the following variables: tooth type (central incisor, canine, and first molar), 2D reference points, and aligner type. Data were analyzed and compared using analysis of variance and Tukey's post-hoc tests (p < 0.05). Results: Tooth type, dental region, and aligner type affected both the gap width and aligner thickness. The aligner thickness remained moderately stable across the arch only in the F22. Conclusions: All thermoformed samples displayed smaller aligner thickness and gap width at anterior teeth and both gingival and coronal centers than at posterior teeth and occlusal surfaces.

• Journal of Welding and Joining
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• 제23권1호
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• pp.55-60
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• 2005

A three-dimensional Gaussian heat source model is modified to include the effects of the gap and thickness-difference for the laser keyhole welding. The gap of the butt joint influences the welding efficiency such that the melting area decreases linearly with the gap. When the different plate thickness is used such as the tailored blank welding, melting areas of the thick and thin plates are predicted by introducing the thickness-difference factor. The calculated results using the modified heat source show reasonably good agreements with the experimental results.

• 한국정밀공학회지
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• 제6권2호
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• pp.58-64
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• 1989

Plastic instability in uniaxial tension of commercial purity Al has been studied with the emphasis of effects of thickness in cold worked specimens and recrystallized specimens. The thickness change gave rise to change in stress state and the amount of strain localization in specimen after diffuse necking. Therefore the thickness of speci- men could control modes of plastic instability. Regardless of recrystallized or cold worked state, the necking mode changed from diffuse necking to local necking, at about 1.5 .approx. 2 mm in thickness.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 춘계학술대회 논문집
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• pp.353-358
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• 2013

Present paper deals with turbulence-airfoil interaction noise and mainly investigates the effects of airfoil thickness on the broadband noise spectrum. The acoustic power radiation from an airfoil is predicted using high-order time-domain method, which is based on the computational aeroacoustic technique solving the linear Euler equations. The homogeneous and isotropic turbulence is generated by utilizing the synthetic turbulence modeling based on random particle method. The airfoils taken into consideration are a flat-plate and a NACA0012 airfoil aligned with uniform mean flow. The effects of airfoil thickness on the radiated inflow turbulence noise are investigated by comparing acoustic power spectrum predicted for each airfoil. The comparison of acoustic power spectrum reveals that the airfoil thickness significantly contributes the high frequency noise reduction.

• 대한기계학회논문집B
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• 제29권8호
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• pp.956-962
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• 2005

A three-dimensional computation was conducted to make a study about effects of the inlet boundary layer thickness on the total pressure loss in a low-speed axial compressor operating at the design condition ($\phi=85\%$) and near stall condition($\phi=65\%$). Differences of the tip leakage flow and hub corner-stall induced by the inlet boundary layer thickness enable the loss distribution of total pressure along the span to be altered. At design condition, total pressure losses for two different inlet boundary layers are almost alike in the core flow region but the larger loss is generated at both hub and tip when the inlet boundary layer is thin. At the near stall condition, however, total pressure loss fer the thick inlet boundary layer is found to be greater than that for the thin inlet boundary layer on most of the span except the region near hub and casing. Total pressure loss is scrutinized through three major loss categories in a subsonic axial compressor such as profile loss, tip leakage loss and endwall loss using Denton's loss model, and effects of the inlet boundary layer thickness on the loss structure are analyzed in detail.

• The Journal of Korean Physical Therapy
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• 제30권2호
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• pp.41-46
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• 2018

Purpose: This study examined the effects of knee extension exercise using blood flow restriction on the changes in the thickness and static balance ability of the tendon of the rectus femoris muscle and achilles tendon. Methods: A total of 30 subjects was were divided into two groups of 15 subjects each. The changes in the thickness and balance of their tendons were measured by ultrasonography and balance equipment. The measurements were taken three times: before the experiment, 4 weeks after, and 8 weeks after. The results were analyzed by repeated measure ANOVA, one-way ANOVA was conducted in cases where there were time-to-group interactions in the intra-individual effects test. Results: Significant differences in the thickness of the tendon of the rectus femoris muscle and Achilles tendon were found between the groups, over time, and in the time-to-group interactions (p<0.05). The changes in balance in both feet when the supporting positions between eye-open and eye-closed states were significantly different in the time-to-group interactions (p<0.05), but were not different between the groups (p>0.05). Conclusion: Knee extension exercise using blood flow restriction leads to significant differences in the increase in tendon thickness and changes in balance, indicating that the results of this study can be utilized as basic data for future studies and for rehabilitation treatment at clinics.

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.183-188
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• 2012

To investigate the influence of the prolactin receptor 3 (PRLR3) gene and the retinol-binding protein 4 (RBP4) gene on the production traits of swine, genotyping was performed on 156 and 141 Berkshire pigs, respectively, that were carefully selected for economic traits. The frequencies of allele A in the PRLR3 locus and allele B in the RBP4 locus were 0.50 and 0.42, respectively. Neither locus was in the Hardy-Weinberg equilibrium. After a genotype was assigned to the individuals whose parents had the homozygous genotype, a statistical analysis was conducted for 291 pigs. The animals with the PRLR3 and RBP4 genotypes included 182 and 227 head, respectively. Even though the genotypic effects of PRLR3 (p<0.05) and RBP4 (p<0.01) had a significant influence on the pigs' back fat thickness, the interaction of both genes was not highly significant in terms of the back fat thickness (p = 0.1235). While the estimated epistasis effects of aaBB and aaBb decreased the back fat thickness and reduced the growth rate, the effects of AAbb and aabb increased the growth rate. Despite the insignificant difference in the PRLR genotypes in terms of the days to 90 kg and the average daily gain, the back fat thickness showed a significant difference (p<0.05), and the additive effect of allele A and the dominant effect of the hetero-genotype were -0.377 and 1.206 mm, respectively. The RBP4 genotypes had a very significant effect (p<0.01) on the back fat thickness, the days to 90 kg, and the average daily gain. The additive effects of allele B of the RBP4 locus on the back fat thickness, the days to 90 kg, and the average daily gain were 0.70 mm, -1.3 days and 6.2 g, respectively. Moreover, the dominant effects of the heterozygote for those traits were 0.63 mm, 9.9 days and -45.0 g, respectively. Allele A of the PRLR3 locus favorably influenced the back fat thickness, the days to 90 kg of the body weight, and the average daily gain and its dominant effect unfavorably influenced those traits. Allele B of RBP4 showed an incremental growth rate and back fat thickness, which could lower the lean meat percentage in the carcass. The RBP4 hetero-genotype negatively affected the pork production. These results strongly imply that the selection of allele A of PRLR3 and allele B of RBP4 would produce highly productive pigs in the Berkshire breed. Careful selection of allele B of RBP4 is required because of the increase in the back fat thickness.

• The Journal of Korean Physical Therapy
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• 제22권4호
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• pp.49-55
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• 2010

Purpose: The purpose of this study was to investigate the effects of isokinetic exercise on muscular performance and thickness of the quadriceps muscle. Methods: Twenty one healthy male students participated in this study. Participants were divided into 2 groups: $60^{\circ}/sec$ of isokinetic exercise (n=7), $180^{\circ}/sec$ (n=7) and $300^{\circ}/sec$ (n=7). Each group did isokinetic exercises 3 times a week for 6 weeks. Each group was measured for peak torque per body weight, average power and total work using a Biodex System 4. Rectus femoris, vastus laterails and vastus medialis were measured for muscle thickness using a SONOACE 6000C. Data were analyzed by repeated measures ANOVA using SPSS 12.0. Results: There was a significant time-related effect in peak torque per body weight, average power and total work. There was a significant time-related effect in the vastus medialis and rectus femoris muscle thickness. However, there was a significant group by time interaction for vastus laterlis muscle thickness. Conclusion: Isokinetic exercise may be an effective method for improving quadriceps muscle performance regardless of angular velocity. However, the thickness of the rectus femoris and vastus medialis muscle may be increased regardless of the angular velocity of the quadriceps muscle the vastus lateralis muscle may only be remarkably improved when doing exercise with low angular velocity.

• The Journal of Korean Physical Therapy
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• 제29권2호
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• pp.69-73
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• 2017

Purpose: This study was conducted to investigate the effects of blood flow restriction and different support surfaces for bridge exercises on the thickness of the transverse abdominis and multifidus, which are trunk-stabilizing muscles. Methods: The study's subjects were 45 adults who were divided into three groups that performed bridge exercises over a six-week period on their respective support surfaces after blood flow restriction. Changes in the thickness of the subjects' transverse abdominis and multifidus muscles were measured using ultrasonography before the experiment, then three and six weeks after the experiment. The changes in each variable over time were analyzed using a repeated-measures analysis of variance (ANOVA). Results: The transverse abdominis showed significant differences in muscle thickness with regard to time and the interaction between time and each group (p<0.05), but no significant differences with regard to changes among groups (p>0.05). The multifidus showed significant differences in muscle thickness with regard to time, the interaction between time and each group, and changes between groups (p<0.05). Conclusion: Blood flow restriction and different support surfaces for bridge exercises led to significant differences in the thickness of the transverse abdominis and multifidus. This study's results may be used as the basis for future studies and for rehabilitation in clinical practice.