• Advances in Computational Design
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• v.2 no.1
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• pp.71-87
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• 2017

This study focuses on the efficiency and applicability of dynamic relaxation methods in form-finding of membrane structures. Membrane structures have large deformations that require complex nonlinear analysis. The first step of analysis of these structures is the form-finding process including a geometrically nonlinear analysis. Several numerical methods for form-finding have been introduced such as the dynamic relaxation, force density method, particle spring systems and the updated reference strategy. In the present study, dynamic relaxation method (DRM) is investigated. The dynamic relaxation method is an iterative process that is used for the static equilibrium analysis of geometrically nonlinear problems. Five different examples are used in this paper. To achieve the grading of the different dynamic relaxation methods in form-finding of membrane structures, a performance index is introduced. The results indicate that viscous damping methods show better performance than kinetic damping in finding the shapes of membrane structures.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.8 no.3
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• pp.293-301
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• 2001

Purpose: The purpose of this study was to investigate the effect of exercise therapy and relaxation therapy on the level of ACTH and cortisol in workers and to determine, from this information, the effectiveness of applied exercise therapy and relaxation therapy as a nursing intervention method for workers experiencing stress. Method: The subjects were divided into an exercise therapy group. a relaxation therapy group, and a control group. The research design was a nonequivalent control group pretest-posttest design (exercise therapy : n=12. relaxation therapy: n=12, control group, the group without exercise or relaxation therapy: n= 12). The subjects in the exercise therapy group were given a particular intensity for each kp over 30 min, bicycle ergometer which uses the LX PE training system before and after four weeks of training. The subjects did 60-70% exercise intensity exercise therapy for eight weeks The relaxation therapy subjects were trained using a modified Jacobson's relaxation technique for eight weeks. The exercise and relaxation therapy groups were trained at the following intensity for eight weeks (3 times/week, 30 min/day). Changes in the levels of ACTH and cortisol were identified. Two-way ANOVA and multiple range test (SNK: Student Newman Keul) were used to examine the effects of exercise therapy and relaxation therapy at four and eight weeks. Result: 1. Changes in the level of ACTH in the relaxation therapy group were statistically significant at .05 level, and were better than that of the exercise therapy group after eight weeks. But there was no significant difference between the exercise therapy group and the control group. 2. Change in the level of cortisol in the relaxation therapy group were statistically significant at .05 level as compared to the exercise therapy group and the control group after four weeks, but not after eight weeks. Also, the relaxation therapy was statistically significant at .05 level after four weeks compared to before treatment, but there was a tendency toward increased cortisol after eight weeks. Conclusion: Relaxation therapy was found to be more effective in stress treatment than exercise therapy and as such is a desirable nursing intervention method for stress hormone reduction in workers.

• Journal of applied mathematics & informatics
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• v.34 no.1_2
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• pp.85-94
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• 2016

In this paper, we first propose a fast one-parameter relaxation (FOPR) method with a scaled preconditioner for solving the saddle point problems, and then we present a formula for finding its optimal parameter. To evaluate the effectiveness of the proposed FOPR method with a scaled preconditioner, numerical experiments are provided by comparing its performance with the existing one or two parameter relaxation methods with optimal parameters such as the SOR-like, the GSOR and the GSSOR methods.

• Journal of Korean Academy of Nursing
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• v.29 no.4
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• pp.855-869
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• 1999

The purpose of this study was to test the effectiveness of self-management relaxation training through biofeedback and progressive muscle relaxation methods. The effectiveness of the experimental methods was tested by measuring the degree of symptoms of stress (SOS), the McNair's profile of Mood States (POMS), the levels of ephinephrine, norepinephrine, pulse rate, blood pressure and natural killer cells. The subjects of this study were sixty six nursing students divided into four groups : two groups were the biofeedback and progressive muscle relaxation groups, the other two groups served as control groups. One was a group of sophomores with no experience at all, the other a junior group without self -management or relaxation training. This study was conducted for eight weeks of clinical practice from April, 26th 1998 to June, 20th 1998. Biofeedback training was done with software developed by J&J company (1-410 form for abdominal respiration training). Progressive muscle relaxation training was done with u audiotape recorded according to Jacobson's Theory. The data were analyzed with frequencies, means, and analysis of covariance using the SPSS program and the significance level of statistics was 5%. The results of the study are : 1) The importance of clinical practice stress reduction is shown in that the level of symptoms of stress in the experimental groups in clinical practice was higher than in the group receiving only a lecture. 2) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in reducing the symptoms of stress under the clinical practice stress conditions. 3) The effectiveness of the biofeedback training relaxation method to reduce symptoms of stress was higher than that of progressive muscle relaxation. 4) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in reducing stressful mood states. 5) The relaxation training methods of biofeedback and progressive muscle relaxation were not effective in reducing epinephrine and norepinephrine levels. 6) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in increaing the number of natural killer cells. 7) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in decreasing high systolic and diastolic values of blood pressure and high pulse rates. In summary, the relaxation methods of biofeedback and progressive muscle relaxation in reducing clinical practice stress were effective in lowering the level of symptoms of stress and the profile of stressful mood states. They were also effective in lowering high blood pressure and pulse rates. The relaxation methods were effective in increasing the number of natural killer cells as part of the immune function. However, relaxation methods were not effective in reducing the catecholamine level. The biofeedback training method for reduction of symptoms of stress was more effective than the progressive muscle relaxation method.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.216-217
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• 2008

In recent years, scientific community has found renewed interest in hypersonic flight research. These hypersonic vehicles undergo severe aero-thermal environment during their flight regimes. During reentry and hypersonic flight of these vehicles through atmosphere real gas effects come into play. The analysis of such hypersonic flows is critical for proper aero-thermal design of these vehicles. The numerical simulation of hypersonic real gas flows is a very challenging task. The present work emphasizes numerical simulation of hypersonic flows with thermal non-equilibrium. Hyperbolic system of equations with stiff relaxation method are identified in recent literature as a novel method of predicting long time behaviour of systems such as gas at high temperature. In present work, Energy Relaxation Method (ERM) has been considered to simulate the real gas flows. Navier-Stokes equations A numerical scheme Advection Upstream Splitting Method (AUSM) has been selected. Navier-Stokes solver along with relaxation method has been used for the simulation of real flow over a circular cylinder. Pressure distribution and heat flux over the surface of cylinder has been compared with experiment results of Hannemann. Present heat flux results over the cylinder compared well with experiment. Thus, real gas effects in hypersonic flows can be modeled through energy relaxation method.

• Korean Journal of Remote Sensing
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• v.5 no.2
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• pp.85-90
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• 1989

A new graph-theoretic clustering method based on relaxation labeling is proposed. More accurate classification is achieved by using relaxation labeling which take advantage of contextual information. Moreover, threshold selection is not needed in this method.

• Journal of Biomedical Engineering Research
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• v.26 no.2
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• pp.87-93
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• 2005

A new method for real-time estimating left ventricular relaxation time constant (T) from the left ventricular (LV) pressure waveform, based on the isovolumic relaxation model, is proposed. The presented method uses a recursive least squares (RLS) algorithm to accomplish real-time estimation. A new criterion to detect the end-point of the isovolumic relaxation period (IRP) for the estimation of T is also introduced, which is based on the pattern analysis of mean square errors between the original and reconstructed pressure waveforms. We have verified the performance of the new method in over 4,600 beats obtained from 70 patients. The results demonstrate that the proposed method provides more stable and reliable estimation of τ than the conventional 'off-line' methods.

• Proceeding of KASS Symposium
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• 2005.05a
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• pp.154-160
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• 2005

The present study is concerned with the application of dynamic relaxation method in the investigation of the large deflection behavior of spatial structures. The dynamic relaxation do not require the computation or formulation of any tangent stiffness matrix. The convergence to the solution is achieved by using only vectorial quantities and no stiffness matrix is required in its overall assembled form. In an effort to evaluate the merits of the methods, extensive numerical studies were carried out on a number of selected structural systems. The advantages of using dynamic relaxation methods, in tracing the post-buckling behavior of spatial structures, are demonstrated.

• Korean journal of food and cookery science
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• v.1 no.1
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• pp.53-56
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• 1985

The rheological models of acorn flour gels with different concentrations were investigated by stress relaxation test. The analysis of relaxation curves by successive residual method revealed that the rheological behavior of acorn flour gels could be expressed by the 7-element, generalized Maxwell model. The equilibrium modulus and modulus of elasticity increased by the increment of acorn flour concentration.

• The Korean Journal of Pain
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• v.28 no.2
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• pp.88-95
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• 2015

Background: Patients suffering from non-cardiac chest pain (NCCP) can interpret their chest pain wrongly despite having received a correct diagnosis. The objective of this study was to compare the efficacy of the relaxation method with metaphor therapy for reducing irrational beliefs and pain severity in patients with NCCP. Methods: Using a randomized controlled trial, 33 participants were randomly divided into a relaxation training group (n= 13), a metaphor therapy group (n = 10), and a control group (n = 10), and were studied for 4 weeks. The two tools used in this research were the Brief Pain Inventory (BPI) index for determining the degree of pain and the short version of the Jones Irrational Belief Test. Metaphor therapy and a relaxation technique based on ${\ddot{O}}$st's treatment were used as the interventions. The collected data were analyzed with a multivariate analysis of covariance (MANCOVA), a Chi-square test, and the Bonferroni procedure of post-hoc analysis. Results: The relaxation training method was significantly more effective than both metaphor therapy and the lack of treatment in reducing the patients' beliefs of hopelessness in the face of changes and emotional irresponsibility, as well as the pain severity. Metaphor therapy was not effective on any of these factors. In fact, the results did not support the effectiveness of metaphor therapy. Conclusions: Regarding the effectiveness of the relaxation method as compared with metaphor therapy and the lack of treatment in the control group, this study suggests that relaxation should be paid greater attention as a method for improving the status of patients. In addition, more studies are needed to determine the effectiveness of metaphor therapy in this area.