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Considering the colorful role of sports in raising the level of physical and mental fitness of citizens, sports facilities are considered one of the city's most important uses. The present research was carried out to spatially analyse sports venues in Mashhad using the geographic information system. According to the type of research, the research method is descriptive and analytical of the survey type, and according to the research purpose, it is applied research. The statistical population of the present study includes all sports fields, sports complexes and swimming pools in Mashhad city in 13 areas within the service area, and the research sample is equal to the statistical population (in full). First, the Information and Communication Technology Organization prepared geographical information of sports venues and maps related to population parameters. Spatial statistical analysis and the method of preparing cluster maps were used to examine the spatial distribution, and in the next step, the hot spot analysis method was used to examine the most important area. All these steps are under the category of Spatial Statics Tools. Spatial Analyst Tools was used to prepare density maps and depict layers. According to the results obtained, the sports facilities are somewhat distributed in clusters, and in some areas, they are randomly distributed, which indicates the uneven distribution of sports facilities in Mashhad. Sports have no significant dispersion, and the concentration of sports places in Mashhad is also in Regions 10 and nine.
 

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The interactions between vortical structures and spherical particles or droplets is of practical issues in two-phase flows. The interactions bring major changes in the flow field particularly when coupled with particle rotation. It is observed that the heat transfer rate is significantly influenced during the time that the vortices’ cores are in the vicinity of the particle. In this paper, transient heat transfer of a rotating spherical particle interacting with a pair of vortices in incompressible and viscous flow is studied using numerical solution of the Navier-Stokes and energy equations in the range of 20≥Re≤100 and non-dimensional rotational velocities 0≤Ω≤1, by computational code which has been developed by the authors. In order to ensure the accuracy of the calculation, the results are compared with numerical data reported in the literature and good agreement between results was observed. Then the effect of circulation direction of two vortices interacting with a particle by spin on its heat transfer rate was investigated. Also distribution of heat transfer coefficient at the particle surface with separate rotation around three different axes in two cases of interacting and non-interacting with vortices is given and the results of heat transfer coefficient are presented. The results show that particle rotation for Ω≤0.5, in both presence and absence of vortices in flow field has negligible effects on the particle heat transfer rate; however, with increasing of particle spin significant effects on heat transfer coefficient has been observed that due to the circulation direction of vortices, different amounts are obtained.

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Spray plays an important role in many engineering and industrial processes. Therefore, it is important to investigate the heat transfer rate of particles in an environment with a wide spectrum of vortical structures resembling turbulent eddies. The interaction between these vortical structures and spherical particles significantly influences the heat transfer rate of particles and their life time. In the present study, transient heat transfer of a spherical particle interacting with random vortexes in an incompressible and viscous flow has been studied using numerical solution of the Navier-Stokes and energy equations at Re=100 by the developed computational algorithm. In order to ensure the accuracy of the calculation, the results are compared with numerical data available in literature, where good agreements were observed. The influential vortex domain around the particle was first identified with simulating two similar vortexes based on their impact on the Nusselt number. Then, using this domain of influence, effects of the number of random vortexes with different structures and positions on the heat transfer rate of the particle were considered. It was found that only 4 or 5 vortexes can well predict the influences of a vortical domain with larger number of vortexes on the heat transfer rate of a particle. The results also indicate that for 4 or more vortexes the Nu varies in a limited range of that for the case with no vortex flow. Furthermore, increasing vortexes sizes, leads to the higher heat transfer rates.

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With the emergence of social networks, the relationships among people found a new horizon. Nowadays, a large number of users sign up in social networks with different goals and they get involved in different activities.On the other hand they affect on one another while their roles and effects are not the same. Some of these users have more effects on the others according to their job status, educational backgrounds and their attractive notes. These users ,whom we call the power nodes, can change the perspective of many users and move them to specific directions. The aim of this research is the identification of the power nodes in Tebyan, as a social network, and such aim was fulfilled through a discovery of the concealed models in the characteristics of the users. This research has followed the standard methodology of CRISP-DM. To reach this end, after the identification of the power nodes, according to the attained sum scores, from three parameters: central relativity, the page rank, and the users activities, a classification was provided from an algorithm tree. The achieved results have shown that the most significant features in determination of a user's power in a social network are education, age and gender.