• International Journal of Aeronautical and Space Sciences
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• v.9 no.2
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• pp.34-40
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• 2008

The aeroelastic analyses for several wing models were performed using the transonic small-disturbance (TSD) equation, which is very efficient, to consider the aerodynamic nonlinearities in the transonic region. For more accurate aerodynamic analysis of airfoil and wing models with shock waves, the viscous equations based on the Green's lag-entrainment equation of boundary-layer effects were coupled with the TSD equation in the transonic region. Finally the aeroelastic characteristics of wing models were investigated through comparisons of the aeroelastic analysis results for wing models considering the change of a thickness of the airfoil section. Moreover, the results of the aeroelastic analysis using the coupled TSD equation with the viscous equations were compared with those using the TSD equation for several wing models.

• Steel and Composite Structures
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• v.16 no.4
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• pp.339-356
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• 2014

This paper presents a study of the nonlinear cylindrical bending of an exponential functionally graded plate (simply called E-FG) with variable thickness. The plate is subjected to uniform pressure loading and his geometric nonlinearity is introduced in the strain-displacement equations based on Von-Karman assumptions. The material properties of functionally graded plates, except the Poisson's ratio, are assumed to vary continuously through the thickness of the plate in accordance with the exponential law distribution; and the solution is obtained using Hamilton's principle for constant plate thickness. In order to analyze functionally graded plate with variable thickness, a numerical solution using finite difference method is used, where parabolic variation of the plate thickness is studied. The results for E-FG plates are given in dimensionless graphical forms; and the effects of material and geometric properties on displacements and normal stresses through the thickness are determined.

• The Journal of Korean Medicine
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• v.26 no.3 s.63
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• pp.176-187
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• 2005

Objectives : This study was carried out to investigate the anti-inflammation, anti-development and curative effects of Oyaksunki-sangamibang (OSKM) on collagen-induced arthritis in Wistar rats and ICR mice. Materials & Methods : D experiment part II, the inhibitory effects of nitric oxide synthesis, pro-inflammatory cytokines, and cyclooxygenase were studied. In experiment part II, paw eduma volume and thickness of ankle joint were measured at 0, 10, 15, and 20 days after immunization. The incidence and arthritis score were evaluated 14 days after immunization, At 15 days after immunization, serum $TNF-\alpha$ was analyzed. In experiment part III paw edema volume and thickness of ankle joint were measured at 0, 10, and 15days after treatment. At 15 days after treatment, serum $TNF-\alpha$ was analyzed. Results : In experiment part I: 1. Nitric oxide synthesis ·md pro-inflammatory cytokines were inhibited significantly by OSKM extract. 2. Cyclooxygenase 2 (COX-2) was inhibited by OSKM extract. In experiment part II: Paw edema volume, thickness of ankle joint and serum $TNF-\alpha$ level of the teated group were significantly decreased compared with the control group at 20 days after immunization. In experiment part III: Incidence of arthritis was $70\%$. OSKM-treated group had no significant change on paw edema volume, thickness of ankle joint and serum $TNF-\alpha$ level. Conclusions : These results indicated that OSKM has anti-inflammation effects on the ICR mouse, and higher inhibitory effects on the onset but lower inhibitory effects on the progression of collagen-induced arthritis in rats.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.1
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• pp.91-98
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• 2018

Purpose : The aim of this study is to determine changes to the thickness of core muscles, e.g., transversus abdominis (TrA), external oblique (EO), and internal oblique (IO), after plank and Kegel exercises and to compare the effects of the two exercise methods. Method : The study divided men and women in their 20s into two groups, Kegel and plank, by randomly allocating 30 males and 30 females to the targeted groups. To achieve the purpose of this study, we examined the thickness of core muscles after the participants performed plank or Kegel exercises. Results : 1. In the Kegel group, abdominal muscle thickness increased with time, and there was a statistically significant difference in the thickness of the TrA. 2. In the plank group, abdominal muscle thickness increased with time, and there was a statistically significant difference in the thickness of the TrA. 3. After the experiment, muscle thickness of the abdominal muscles in the plank exercise group were higher, but there was no significant difference between the Kegel exercise group and the plank exercise group. Conclusion : Both plank and Kegel exercises are recommended for core muscle stabilization, and based on the results of this study, Kegel exercise is either used as a core stabilizing exercise or as a plank exercise for the weaker patients or women.

• The Journal of Korean Physical Therapy
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• v.29 no.5
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• pp.265-270
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• 2017

Purpose: This study examined the effects of neck stabilization exercises with vibratory stimulation on the neck disability index and thickness of the deep neck flexor. Methods: Thirty subjects (control group=15, experimental group=15) with mild neck pain were enrolled in the study. The control group underwent craniocervical flexion exercise (control group, CG) and the experimental group was given craniocervical flexion exercise with vibratory stimulus (experimental group, EG) (3 sets, 3 times per week for 6 weeks). To examine the effects of exercise, the subjects were evaluated using the neck disability index (NDI), the thickness of the deep neck flexor muscle, and muscle strength. An independent and paired t-test were used to compare the effects of the exercise between the groups. Results: The NDI score of the two groups increased significantly after 6 weeks of treatment (p<0.001) and there was a significant difference between the EG group at 3 weeks (p<0.05) and 6 weeks (p<0.01). The thickness of the deep neck flexor in the CG group increased significantly after 6 weeks of treatment in all pressure stages (p<0.001). The EG group showed a significant increase after 3 and 6 weeks of treatment in all pressure stage (p<0.001), and 22 mmHg, a significant difference between 3 and 6 weeks (p<0.05) and among 24, 28, and 30 mmHg at 6 weeks (p<0.05). The maximum muscle strength of the deep neck flexion muscles increased significantly in the two groups after 6 weeks of treatment (p<0.001) and there was significant difference between the EG group at 6 weeks (p<0.01). Conclusion: Craniocervical flexion exercise with vibratory stimulus decreases the NDI, and increases the thickness of the deep neck flexor and maximum muscle strength of the deep neck flexion muscles in patients with mild neck pain.

• Magazine of the Korean Society of Agricultural Engineers
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• v.29 no.2
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• pp.39-52
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• 1987

This study was to investigate the effects of soil-structure relative stiffness on the structural characteristics of the cylindrical tank supported by soil. A standard example model of the farm silo rested on the Winkler's subsoil model was used for the analysis of soil-structure coupled system. In this paper, Winkler's constants 4,15 and l00kg/cm$^2$/cm were considered and the bottom plate thicknesses of the farm silo 20, 30, 50,100 and 150cm were adopted. For the given model the effects of bottom plate thickness were the most conspicuous at weakest Winkler's constant 4kg/ cm$^2$/cm. While when Winkler's constant is l00kg/cm$^2$/cm, the effect of the bottom plate thickness is almost negligible. On the other hand, when the bottom plate thickness is more than 100cm, the effects of elastic foundation were aknost disappeared. In design practice, it is hoped that the thicknesses of bottom plate should be determined reasonably because of it's considerable effect on the structural characteristics as the lOOcm thickness of bottom plate will not be practical value in usual sites.

• Journal of Sasang Constitutional Medicine
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• v.27 no.2
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• pp.240-253
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• 2015

Objectives The aim of this study was to investigate the effects of GalGunSeungGi-Tang (GST) on allergic contact dermatitis (ACD) induced by 2,4-dintrochlorobenzone (DNCB) Methods In this study, The changes of body weight, ear weight, ear thickness, spleen weight, dorsum skin thickness, symptom score by eyesight, histological finding, proliferation rates of splenocyte in vitro and in vivo are investigated to check effects of GST. The mice are divided into four group; Normal (naive mice), Control (DW administered), GST-L (GST 500mg/Kg/day administered), GST-H (GST 1,000mg/Kg/day administered). Results GST inhibited weight of ear significantly (P < 0.05) and also thickness (P < 0.01). In addition, There are significant decrease in thickness of dorsum skin and proliferation rates of splenocyte in vivo in GST administered group. Finally, GST reduced symptom score and hyperkeratosis, hyperpigmentation, increase of granulocyte and parakeratosis in histological finding. Conclusions These results suggest that GST can decrease symptoms of ACD.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1289-1291
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• 1993

The hydrogenation effects on characteristics of polycrystalline silicon thin film transistors(poly-Si TFT's) of which the channel length varies from $2.5{\mu}m\;to\;20{\mu}m$ and poly-Si layer thickness is 50, 100, and 150 nm was investigated. After 1 hr hydrogenation annealing by PECVD, the threshold voltage shift decreased dependent on the channel length, but channel width may not alter the threshold voltage shift. In addition to channel length, the active poly-Si layer thickness may be an important parameter on hydrogenation effects, while gate poly-Si thickness may do not influence on the characteristics of TFT's. Considering our experimental results, we propose that channel length and active poly-Si layer thickness may be a key parameters of hydrogenation of poly-Si TFT's.

• Structural Engineering and Mechanics
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• v.74 no.2
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• pp.175-187
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• 2020

The theories having been developed thus far account for higher-order variation of transverse shear strain through the depth of the beam and satisfy the stress-free boundary conditions on the top and bottom surfaces of the beam. A shear correction factor, therefore, is not required. In this paper, the effect of surface on the axial buckling and free vibration of nanobeams is studied using various refined higher-order shear deformation beam theories. Furthermore, these theories have strong similarities with Euler-Bernoulli beam theory in aspects such as equations of motion, boundary conditions, and expressions of the resultant stress. The equations of motion and boundary conditions were derived from Hamilton's principle. The resultant system of ordinary differential equations was solved analytically. The effects of the nanobeam length-to-thickness ratio, thickness, and modes on the buckling and free vibration of the nanobeams were also investigated. Finally, it was found that the buckling and free vibration behavior of a nanobeam is size-dependent and that surface effects and surface energy produce significant effects by increasing the ratio of surface area to bulk at nano-scale. The results indicated that surface effects influence the buckling and free vibration performance of nanobeams and that increasing the length-to-thickness increases the buckling and free vibration in various higher-order shear deformation beam theories. This study can assist in measuring the mechanical properties of nanobeams accurately and designing nanobeam-based devices and systems.

• Structural Engineering and Mechanics
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• v.34 no.2
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• pp.143-157
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• 2010

This paper presents theoretical solutions for the three-dimensional (3D) stress field in an infinite isotropic elastic plate containing a through-the-thickness circular hole subjected to far-field in-plane loads by using Kane and Mindlin's assumption. The dangerous position, where the premature fracture or failure of the plate will take place, the expressions of the tangential stress at the surface of the hole and the out-of-plane stress constraint factor are found in a concise, explicit form. Based on the present theoretical solutions, a comprehensive analysis is performed on the deviated degree of the in-plane stresses from the related plane stress solutions, stress concentration and out-of-plane constraint, and the emphasis has been placed on the effects of the plate thickness, Poisson's ratio and the far-field in-plane loads on the stress field. The analytical solution shows that the effects of the plate thickness and Poisson's ratio on the deviation of the 3D in-plane stress components is obvious and could not be ignored, although their effects on distributions of the in-plane stress components are slight, and that the effect of the far-field in-plane loads is just on the contrary of that of the above two. When only the shear stress is loaded at far field, the stress concentration factor reach its peak value about 8.9% higher than that of the plane stress solutions, and the out-of-plane stress constraint factor can reach 1 at the surface of the hole and is the biggest among all cases considered.