جستجوی مقالات مرتبط با کلیدواژه « Phase Space » در نشریات گروه « علوم انسانی »

The aim of present study was to examine the difference between the cardiovascular performance of women and men due to running effects using phase space dynamics.

Fifty four University students were voluntarily participated in this study and divided in two groups’ male (34 participants, 21.68±1.66 years old and 67.01±9.77 Kg) and female (20 participants, 22.4±5.33 years old and 54.1±5.79 Kg). Heart rate variability (HRV) parameters as a function of the cardiovascular system indices measured in these subjects. Using drawing the phase space dynamics and applying the Poincaré section, the features of the time-domain extracted. Data were analyzed by an independent t-test with a significance level (p<0.05).

The results of this study showed that the HRV parameters, i.e., P-Com, PNN50, HRmax, Tr, and  in men’s group significantly altered compared to the women’s group. We found that the average time for reach to maximum heart rate was higher in the women's group and that the average PNN50 and rMSSD parameters in the men's, were higher than the women's, which was stimulated by the parasympathetic and vagus nerve and affected. So this point demonstrated the slowest rhythm of the heartbeat in men.

According to the experimental results, during exercise activities, there is a phenomenon of hysteresis in the cardiac phase space arising from the chaotic and nonlinear dynamics of the biological system in the human body. Therefore, the analysis of these parameters indicates that the intervals between two consecutive beats are higher in men. Thus, they have fewer beats rhythm. Besides, this group is almost more physically fit than women are.

Non-linear dynamic systems show different behaviors so that they can be applied to interpret a variety of seemingly random economic phenomena. The chaos theory provides a new approach to invest the trend changes of non-linear dynamic systems in monetary and financial markets. This paper investigates the behavior of economic growth in Iran using the chaos theory، BDS and bootstrap test، maximum Lyapunov exponent، the Hurst exponent and phase space reconstruction. The aim of this study is to examine whether economic growth has an independent identical distribution or follows a non-linear (random or chaotic) process. The results of BDS test and the Hurst exponent indicate that economic growth has a non-linear process. The results of two chaotic tests include maximum Lyapunov exponent and phase space reconstruction also confirm the existence of chaos in GDP.

Most researches carried out in the field of Social Capital have weighed each of the variables of social capital with various measuring models (especially trust and social networks) neglecting the inter relation of the forming variable and consequently, have introduced the degree of each of the forming variables as the total measure of Social Capital itself. In this paper, effort has been put into describing the current measuring methods and outlining the criticisms applied to each of them. The main focus of the article is on the assessment of the synergic interaction among the forming variables of social capital as a totality. Therefore, correlation of forming variables is the research method used. With regard to the complex relationship between the forming variables of social capital, complexity has been used as the major appropriate model. In this models with a functional definition basis and statement of the reciprocal and non-reduction relation between the variables, social capital has formed a complex function. Thus, estimating the phase space of each variable of the social capital and solving the partial differentiation equations system are introduced as the useful and efficient tools of evaluating Social Capital function. Resault: Exploiting the complexity mathematics is suggested to be the suitable method for measuring Social Capital.