• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.28 no.3
• /
• pp.33-40
• /
• 2022

Background: The cross-body and the sleeper stretches have been used to improve posterior shoulder tightness (PST). However, such stretching techniques may not always help achieve scapular stability and may even aggravate patient's symptoms. Therefore, a new stretching technique (passive glenohumeral internal rotation with bridging) was developed as a more effective method that may allow for greater scapular stability without aggravating the symptoms. Thus, this study aimed to examine and compare this novel stretching technique to determine its effect on the range of motion (ROM) and acromio-humeral distance (AHD) in patients with glenohumeral internal rotation deficits (GIRD) with posterior shoulder tightness. Methods: A total of 30 symptomatic patients with asymmetrical GIRD were randomly assigned to two groups: the novel stretching group (n=15) and the joint mobilization group (n=15). The intervention was conducted twice a week for a total of four weeks. The ROM of shoulder internal rotation was measured by a goniometer and the AHD was evaluated by an X-ray before and after the intervention. Results: Both the treatments improved ROM and AHD in patients with GIRD (p<.05). However, the improvements in internal rotation ROM and AHD in the novel stretching group were significantly greater than that of the subjects in the mobilization group. There was a significant difference between the two groups (p<.05). Conclusion: These results show that both novel stretching and joint mobilization improved ROM and AHD in patients with GIRD with PST. However, novel stretching was more effective than joint mobilization.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.5
• /
• pp.19-23
• /
• 2013

TIn this paper, we propose a novel fuzzy stretching method that adopts a triangle type fuzzy membership function to control the highest and lowest brightness limit dynamically. As an essential procedure to enhance the brightness contrast, stretching is an important procedure in color image processing. While popular Ends-in Search stretching method should be provided fixed minimum and maximum brightness threshold from experience, our proposed method determines them dynamically by fuzzy membership functions. The minimum and maximum limit is determined by computing the lowest and highest pixel value according to the membership degree of our designed triangle type membership function. The experiment shows that the proposed method result in far less skewed histogram than those of Ends-in Search stretching thus successfully verifies its effectiveness.

• Physical Therapy Korea
• /
• v.30 no.1
• /
• pp.59-67
• /
• 2023

Background: Posterior capsule tightness (PCT), commonly seen in overhead athletes, is a soft tissue adaptation that is also noted in non-throwers. PCT is associated with scapular and humeral kinematic alterations, significant restriction of shoulder internal rotation (IR) range of motion (ROM), and significant scapular anterior tilting. Sleeper and cross-body stretches (CBS) are suggested for PCT and IR deficits, and have been modified since introduction. A novel modified sleeper stretch (NMSS) was designed in this study to prevent the risk of anterior translation of the humeral head. Though the effects of posterior shoulder stretching exercise have been widely studies, to the best of our knowledge, no previous studies have investigated the effectiveness of posterior shoulder exercises in decreasing scapular anterior tilting. Objects: To compare the immediate effects of two posterior shoulder stretching exercises (NMSS and CBS) on scapular anterior tilting and shoulder IR ROM. Methods: Thirty-two subjects with anteriorly tilted scapula and IR deficits [mean age: 24.3 ± 2.5 years; 15 males and 17 females] participated in this study. Subjects were randomly assigned to either the NMSS or CBS groups. Scapular anterior tilting (at rest and at shoulder 60° active IR) and shoulder IR ROM were measured before and immediately after intervention. Results: Scapular anterior tilting significantly decreased, while the shoulder IR ROM significantly increased in both groups. However, there was no significant group-by-time interaction effect or significant difference between the groups. Conclusion: Both stretching exercises were effective in restoring shoulder IR ROM and decreasing scapular anterior tilting.

• Steel and Composite Structures
• /
• v.15 no.2
• /
• pp.221-245
• /
• 2013

This paper presents an analytical solution to the thermomechanical bending analysis of functionally graded sandwich plates by using a new hyperbolic shear deformation theory in which the stretching effect is included. The modulus of elasticity of plates is assumed to vary according to a power law distribution in terms of the volume fractions of the constituents. The core layer is still homogeneous and made of an isotropic ceramic material. The effects of functionally graded material (FGM) layer thickness, volume fraction index, layer thickness ratio, thickness ratio and aspect ratio on the deflections and stresses of functionally graded sandwich plates are investigated.

• Steel and Composite Structures
• /
• v.18 no.3
• /
• pp.793-809
• /
• 2015

In this scientific work, constructing of a novel shear deformation beam model including the stretching effect is of concern for flexural and free vibration responses of functionally graded beams. The particularity of this model is that, in addition to considering the transverse shear deformation and the stretching effect, the zero transverse shear stress condition on the beam surface is assured without introducing the shear correction parameter. By employing the Hamilton's principle together with the concept of the neutral axe's position for such beams, the equations of motion are obtained. Some examples are performed to demonstrate the effects of changing gradients, thickness stretching, and thickness to length ratios on the bending and vibration of functionally graded beams.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.12
• /
• pp.37-45
• /
• 2010

This paper proposes a novel contrast enhancement method which determines the stretching ranges based on the distribution densities of segmented sub-histogram. In order to enhance the quality of image effectively, the contrast histogram is segmented into sub-histograms based on the density in each brightness region. Then the stretching range of each sub-histogram is determined by analysing its distribution density. The higher density region is extended wider than lower density region in the histogram. This method solves the over stretching problem, because it stretches using density rate of each area on the histogram. To evaluate the performance of the proposed algorithm, the experiments have been carried out on complex contrast images, and its superiority has been confirmed by comparing with the conventional methods.

• Advances in nano research
• /
• v.11 no.6
• /
• pp.621-640
• /
• 2021

Effect of thickness stretching on mechanical behavior of functionally graded (FG) carbon nanotubes reinforced composite (CNTRC) laminated nanoplates resting on elastic foundation is analyzed in this paper using a novel quasi 3D higher-order shear deformation theory. The key feature of this theoretical formulation is that, in addition to considering the thickness stretching effect, the number of unknowns of the displacement field is reduced to four, and which is more than five in the other models. Single-walled carbon nanotubes (SWCNTs) are the reinforced elements and are distributed with four power-law functions which are, uniform distribution, V-distribution, O-distribution and X-distribution. To cover various boundary conditions, an analytical solution is developed based on Galerkin method to solve the governing equilibrium equations by considering the nonlocal strain gradient theory. A modified two-dimensional variable Winkler elastic foundation is proposed in this study for the first time. A parametric study is executed to determine the influence of the reinforcement patterns, power-law index, nonlocal parameter, length scale parameter, thickness and aspect ratios, elastic foundation, thermal environments, and various boundary conditions on stresses, displacements, buckling loads and frequencies of the CNTRC laminated nanoplate.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.11
• /
• pp.2540-2545
• /
• 2015

In this paper, we propose a novel method to extract appendix from ultrasound image automatically to avoid such subjectivity issue. In the process, we apply a series of image processing algorithms such as Ends_in search stretching for emphasizing brightness contrast and binarization, region labelling, and cubic spline interpolation for extracting lower bound fasicia line that is the base of extracting the appendix. Knowing that the appendix is located at the lower organ area below the bottom fascia line, we conduct a series of image processing techniques to find the fascia line correctly. And then we apply ART2 algorithm to the organ area in order to extract appendix accurately. Through experiment, the effectiveness of the proposed method is verified based on the field experts' evaluations.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.1
• /
• pp.658-665
• /
• 2015

In the production of medical images, noise reduction and contrast enhancement are important methods to increase qualities of processing results. By using the edge-based denoising and adaptive nonlinear histogram stretching, a novel medical image enhancement algorithm is proposed. First, a medical image is decomposed by wavelet transform, and then all high frequency sub-images are decomposed by Haar transform. At the same time, edge detection with Sobel operator is performed. Second, noises in all high frequency sub-images are reduced by edge-based soft-threshold method. Third, high frequency coefficients are further enhanced by adaptive weight values in different sub-images. Finally, an adaptive nonlinear histogram stretching method is applied to increase the contrast of resultant image. Experimental results show that the proposed algorithm can enhance a low contrast medical image while preserving edges effectively without blurring the details.

• Geomechanics and Engineering
• /
• v.14 no.6
• /
• pp.519-532
• /
• 2018

In this work, two dimensional (2D) and quasi three-dimensional (quasi-3D) HSDTs are proposed for bending and free vibration investigation of functionally graded (FG) plates using hyperbolic shape function. Unlike the existing HSDT, the proposed theories have a novel displacement field which include undetermined integral terms and contains fewer unknowns. The material properties of the plate is inhomogeneous and are considered to vary continuously in the thickness direction by three different distributions; power-law, exponential and Mori-Tanaka model, in terms of the volume fractions of the constituents. The governing equations which consider the effects of both transverse shear and thickness stretching are determined through the Hamilton's principle. The closed form solutions are deduced by employing Navier method and then fundamental frequencies are obtained by solving the results of eigenvalue problems. In-plane stress components have been determined by the constitutive equations of composite plates. The transverse stress components have been determined by integrating the 3D stress equilibrium equations in the thickness direction of the FG plate. The accuracy of the present formulation is demonstrated by comparisons with the different 2D, 3D and quasi-3D solutions available in the literature.