relaxation method
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Author(s):  
Biswajit Sharma ◽  
K. Mukhopadhyay

The COVID-19 pandemic has had an influence on people's physical, emotional, and social health all across the world. Due to mental health issues that resulted in anxiety, sadness, and post-traumatic stress disorder symptoms among a variety of demographic groups, including healthcare staff, the general public, patients, and those who were confined. Yoganidra Meditation is an excellent meditative relaxation method for relieving stress and tension and achieving profound psychological and physiological benefits. According to studies, Yognidra can also be utilized as a therapeutic approach to treat psychological problems such as anxiety, anger, and sleeplessness, as well as psychosomatic illnesses such as asthma, coronary heart disease, cancer, and hypertension. The purpose of the study is to critically analyze the findings of other researchers on the application of Yognidra to reliving the stress of an individual. The study is a conceptual and qualitative Meta-analysis, and it deals with global stress management.


Mathematics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 81
Author(s):  
Napat Harnpornchai ◽  
Wiriyaporn Wonggattaleekam

Nash Equilibrium (NE) plays a crucial role in game theory. The relaxation method in conjunction with the Nikaido–Isoda (NI) function, namely the NI-based relaxation method, has been widely applied to the determination of NE. Genetic Algorithm (GA) with adaptive penalty is introduced and incorporated in the original NI-based relaxation method. The GA enhances the capability in the optimization step for computing the optimum response function. The optimization of the non-convex and non-concave NI function is made possible by GA. The proposed method thus combines the advantageous feature of the GA in its optimization capability and that of the relaxation method in its implementation simplicity together. The applicability of the method is shown through the illustrative examples, including the generalized Nash Equilibrium problem with nonlinear payoff functions and coupled constraints, the game with multiple strategic variables for individual players, and the non-differentiable payoff functions. All test example results suggest the appropriate crossover and mutation rate to be 0.05 and 0.002 for use in GA. These numbers are closed to the recommended values by DeJong. The proposed method shows its capability of finding correct NEs in all test examples.


2021 ◽  
Vol 15 (4) ◽  
pp. 8617-8623
Author(s):  
H.N. Yakin ◽  
Nik Abdullah Nik Mohamed ◽  
M.R.M. Rejab

Peridynamics (PD) is a new tool, based on the non-local theory for modelling fracture mechanics, where particles connected through physical interaction used to represent a domain. By using the PD theory, damage or crack in a material domain can be shown in much practical representation. This study compares between Prototype Microelastic Brittle (PMB) damage model and a new Quasi-Brittle (QBR) damage model in the framework of the Bond-based Peridynamics (BBPD) in terms of the damage plot. An in-house code using Matlab was developed for BBPD with inclusion of both damage models, and tested for a quasi-static problem with the implementation of Adaptive Dynamic Relaxation (ADR) method in the theory in order to get a faster steady state solutions. This paper is the first attempt to include ADR method in the framework of BBPD for QBR damage model. This paper analysed a numerical problem with the absence of failure and compared the displacement with literature result that used Finite Element Method (FEM). The obtained numerical results are in good agreement with the result from FEM. The same problem was used with the allowance of the failure to happen for both of the damage models; PMB and QBR, to observe the damage pattern between these two damage models. PMB damage model produced damage value of roughly twice compared to the damage value from QBR damage model. It is found that the QBR damage model with ADR under quasi-static loading significantly improves the prediction of the progressive failure process, and managed to model a more realistic damage model with respect to the PMB damage model.


Author(s):  
Jian-Feng Cai ◽  
Ronald C Chen ◽  
Junyi Fan ◽  
Hao Gao

Abstract Objective: Deliverable proton spots are subject to the minimum monitor-unit (MMU) constraint. The MMU optimization problem with relatively large MMU threshold remains mathematically challenging due to its strong nonconvexity. However, the MMU optimization is fundamental to proton radiotherapy (RT), including efficient IMPT, proton arc delivery (ARC), and FLASH-RT. This work aims to develop a new optimization algorithm that is effective in solving the MMU problem. Approach: Our new algorithm is primarily based on stochastic coordinate decent (SCD) method. It involves three major steps: first to decouple the determination of active sets for dose-volume-histogram (DVH) planning constraints from the MMU problem via iterative convex relaxation method; second to handle the nonconvexity of the MMU constraint via SCD to localize the index set of nonzero spots; third to solve convex subproblems projected to this convex set of nonzero spots via projected gradient descent method. Main results: Our new method SCD is validated and compared with alternating direction method of multipliers (ADMM) for IMPT and ARC. The results suggest SCD had better plan quality than ADMM, e.g., the improvement of conformal index (CI) from 0.51 to 0.71 during IMPT, and from 0.22 to 0.86 during ARC for the lung case. Moreover, SCD successfully handled the nonconvexity from large MMU threshold that ADMM failed to handle, in the sense that (1) the plan quality from ARC was worse than IMPT (e.g., CI was 0.51 with IMPT and 0.22 with ARC for the lung case), when ADMM was used; (2) in contrast, with SCD, ARC achieved better plan quality than IMPT (e.g., CI was 0.71 with IMPT and 0.86 with ARC for the lung case), which is compatible with more optimization degrees of freedom from ARC compared to IMPT. Significance: To the best of our knowledge, our new MMU optimization method via SCD can effectively handle the nonconvexity from large MMU threshold that none of the current methods can solve. Therefore, we have developed a unique MMU optimization algorithm via SCD that can be used for efficient IMPT, proton arc delivery (ARC), FLASH-RT, and other particle RT applications where large MMU threshold is desirable (e.g., for the delivery of high dose rates or/and a large number of spots).


Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2078
Author(s):  
Ajmal Ali ◽  
Thabet Abdeljawad ◽  
Azhar Iqbal ◽  
Tayyaba Akram ◽  
Muhammad Abbas

In this study, a new modified group iterative scheme for solving the two-dimensional (2D) fractional hyperbolic telegraph differential equation with Dirichlet boundary conditions is obtained from the 2h-spaced standard and rotated Crank–Nicolson FD approximations. The findings of new four-point modified explicit group relaxation method demonstrates the rapid rate of convergence of proposed method as compared to the existing schemes. Numerical tests are performed to test the capability of the group iterative scheme in comparison with the point iterative scheme counterparts. The stability of the derived modified group method is proven by the matrix norm algorithm. The obtained results are tabulated and concluded that exact solutions are exactly symmetric with approximate solutions.


Author(s):  
Qing Yu ◽  
Xianbin Liu

Abstract In the present paper, noise-induced escape from the domain of attraction of a stable fixed point of a fast-slow insect outbreak system is investigated. According to Dannenberg's theory(Dannenberg PH, Neu JC, 2014)[1], different noise amplitude ratios μ lead to the change of the Most Probable Escape Path(MPEP). Therefore, the research emphasis of this paper is to extend their study and discuss the changes of the MPEPs in more detail. Firstly, the case for μ=1, wherein the MPEP almost traces out the critical manifold, is considered. Via projecting the full system onto the critical manifold, a reduced system is obtained and the quasi-potential of the full system can be partly evaluated by that of this reduced system. In order to test the accuracy of the computed MPEP, a new relaxation method is then presented. Then, as μ converges to zero, an improved analytical method is given, through which a better approximation for the MPEP at the turning point is obtained. And then, in the case that the value of μ is moderate, wherein the MPEP will peel off the critical manifold, to determine the changing point of the MPEP on the critical manifold, an effective numerical algorithm is given. In brief, in this paper, a complete investigation on the structural changes of the MPEPs of a fast-slow insect outbreak system under different values of μ is given, and the results of the numerical simulations match well with the analytical ones.


Mathematics ◽  
2021 ◽  
Vol 9 (19) ◽  
pp. 2514
Author(s):  
Anwar Shahid ◽  
Mohamed S. Mohamed ◽  
Muhammad Mubashir Bhatti ◽  
Mohammad Hossein Doranehgard

The present study deals with the Darcy–Brinkman–Forchheimer model for bioconvection-stratified nanofluid flow through a porous elastic surface. The mathematical modeling for MHD nanofluid flow with motile gyrotactic microorganisms is formulated under the influence of an inclined magnetic field, Brownian motion, thermophoresis, viscous dissipation, Joule heating, and stratifi-cation. In addition, the momentum equation is formulated using the Darcy–Brinkman–Forchheimer model. Using similarity transforms, governing partial differential equations are reconstructed into ordinary differential equations. The spectral relaxation method (SRM) is used to solve the nonlinear coupled differential equations. The SRM is a straightforward technique to develop, because it is based on decoupling the system of equations and then integrating the coupled system using the Chebyshev pseudo-spectral method to obtain the required results. The numerical interpretation of SRM is admirable because it establishes a system of equations that sequentially solve by providing the results of the first equation into the next equation. The numerical results of temperature, velocity, concentration, and motile microorganism density profiles are presented with graphical curves and tables for all the governing parametric quantities. A numerical comparison of the SRM with the previously investigated work is also shown in tables, which demonstrate excellent agreement.


2021 ◽  
Vol 12 (3) ◽  
pp. 26-31
Author(s):  
Danylova T.V. ◽  
◽  
Salata G.V. ◽  
Semenov Yu. O. ◽  
◽  
...  

Nowadays, the problem of diagnosis, interpretation and selection of treatment options for phobic anxiety disorders is becoming more acute taking into account the multidimensionality of a human being. The data obtained on psychopharmacotherapy show its moderate effectiveness for phobic anxiety disorders. The combination of psychopharmacotherapy and psychotherapy, which often plays a leading role in the treatment process, works much better. The paper aims at analyzing psychotherapeutic treatment options for phobic anxiety disorders, such as exposure therapy, cognitive-behavioral therapy, group therapy and self-help groups, hypnotherapy, mindfulness, meditation, deep breathing, progressive muscle relaxation method. There are pros and cons for both psychopharmacological and psychotherapeutic treatment options. Therefore, the choice of the most effective treatment options should be determined after an in-depth examination of a patient and carried out by a multidisciplinary team of specialists.


Author(s):  
Alma Trazivuk ◽  
Andre Alberts ◽  
Adrijan Baric ◽  
Vladimir Ceperic

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