check the dynamic response of a punch to human head

Brain hurt due to a strike to head is a serious and important social and public health problem and has attracted the attention of many researchers in recent years (Chen, ٢٠١١). These harmes may occur in some cases without any apparent brain hurt but may lead to severe marrowy hurts, unconsciousness and finentirey death. The athletes in fighting sports like boxing, karate, taekwondo are exposed to hard strikes to headenimpositiond by frequent and targeted strikes to rival’s body and mainly to the head. Superficial brain harmes due to strikes are very joint in these sports. Most of brain harmes and traumas occur due to direct and frequent strikes from near distances to the head in martial arts competitions. Although these frequent strikes may seemingly have no alarming primary effects, they reason frequent traumas in brain inside the skull and thisconclusion in internal bleeding and finentirey serious problems which lead in some cases to death. When a hard strike is delivered to head, there may be no apparent bleeding or skull fracture, but that strike may have reasond an internal marrowy hurt which may further lead to contusion, blood vessel rupture or hurt to cranial nerves.Most of the previous perusales have investigated the strike to head and the biomechanics of hurts sustained following concussion due to traffic incidents or incidents in sports like footbentire and several perusales have deal with concussions due to direct punches to head and frequent strikes for getting points in martial arts competitions. Walilko et al. (٢٠٠٥) investigated the imposition of the direct punches of seven Olympic boxers in five various weight classes using a three dimensional model and calculated the average linear and angular pelt and reached to a measure for marrowy hurt. Viano et al. (٢٠٠٥) perusaled the punch imposition of eleven Olympic boxers with a ٣D model. They investigated not just the direct punch but also hook and uppercut strikes in this investigation and came to the conclusion that punches reason less harmes bereason of the short time of accelerating and therefore do not meet the measure for brain hurt in short time. Al-Bsharat et al. (١٩٩٩) used a ٣D skull model to investigate the role of impact velocity in themagnitude of produced cranial stress during a front strike. They achieved the magnitudes of communication imposition and intracranial pressure for the applied imposition.Zong et al. (٢٠٠٦) available a ٣D limited element model of human head in their investigation and analyzed it to assess the possibility of head harm due to the applied strikes. The high possibility of spinal cord harm as a conclusion of the wave of movement inside the head was also analyzed in this investigation. Johnsonand Young (٢٠٠٥) created a model to simulate the human head reaction to strike and evaluate the sensitivity of the model to spacing parameters. For timely simulation of a strike to head which reasons marrowy hurts,Khurana et al. (٢٠١٢) reviewed the scientific literature on sport incidents and reasons, pathophysiology,assessment short-term and long-term consequences of concussion. Pinnoji and Mahajan (٢٠٠٦) used a limitedelement model of a front strike to head covered with helmet to investigate the effect of foam thickness on communication impositions, pressure and energy absorption during the strike. Stern et al. (٢٠١١) carried out a investigation to investigate the long-term consequences of trauma as a conclusion of frequent strikes. They also concentrated on risk factors and in vivo diagnosis. Asgharpour et al. (٢٠١٤) analyzed the strike to head of human cadaver using a ٣D limited element model. Notwithstanding of having a relatively perfect limited element model of human head, they have selected either inefficient or unsuitable mechanical feature for spacing parts of their model. Post et al. (٢٠١١) analyzed a limited element model to investigation the effect of loading curves on prediction of brain hurt. This research used the mentioned model to analyze three loading curves applied independently in each axis of linear and angular pelt investigated and validated their effects on the prediction of concussion. In the available investigation some factors including the shift, normal stress and the cut stress produced by a punch to the head of a Wushu practitioner wearing a Sanda helmet is simulated and analyzed using limited element modeling. The areas and planes of maximum stress and shift in each tissue were also determined. Additionentirey, as mentioned before the cerebrospinal fluid has been rarely taken into account in the previous papers as hydro elastic fluid. For eliminating some of these deficiencies a ٣D limited element model was engage with viscoelastic materials in the model of human head which defined by related Perony series and the cerebrospinal fluid was considered as a hydrostatic fluid to increase the accuracy of the used limited element model in comparison with the other previous models.