Stereotactic surgery is based on a high degree of accuracy in defining and localising intracranial targets and placing surgical tools. Brain shift can influence its accuracy significantly. Deep brain stimulation of th...Stereotactic surgery is based on a high degree of accuracy in defining and localising intracranial targets and placing surgical tools. Brain shift can influence its accuracy significantly. Deep brain stimulation of the subthalamic nucleus can markedly change the quality of life of patients with advanced Parkinson’s disease, but the outcome depends on the quality of electrode placement. A patient is reported in whom the placement of the second electrode was not successful. Deformation field analysis of pre-and post-operative three dimensional magnetic resonance images showed an intraoperative brain movement of 2 mm in the region of the subthalamic nucleus (the target point). Electrode repositioning resulted in efficient stimulation effects. This case report shows the need to reduce risk factors for intraoperative brain movement and demonstrates the ability of deformation field analysis to quantify this complication.展开更多
Fault Ride-Through (FRT) capabilities set up according to the grid codes may affect the performance of related protective elements during fault periods. Therefore, in this paper the coordination between the FRT capa...Fault Ride-Through (FRT) capabilities set up according to the grid codes may affect the performance of related protective elements during fault periods. Therefore, in this paper the coordination between the FRT capability and over-current protection of DFIG Wind Generators in MV networks is investigated. Simulation test cases using MATLAB-Simulink are implemented on a 365-MW wind farm in AL-Zaafarana, Egypt. The simulation results show the influence of the FRT capability on the protective relaying coordination in wind farms, showing that the FRT may work in situations where is were expected not to work, and then disabling the over-current protection, which should have worked in this situation.展开更多
文摘Stereotactic surgery is based on a high degree of accuracy in defining and localising intracranial targets and placing surgical tools. Brain shift can influence its accuracy significantly. Deep brain stimulation of the subthalamic nucleus can markedly change the quality of life of patients with advanced Parkinson’s disease, but the outcome depends on the quality of electrode placement. A patient is reported in whom the placement of the second electrode was not successful. Deformation field analysis of pre-and post-operative three dimensional magnetic resonance images showed an intraoperative brain movement of 2 mm in the region of the subthalamic nucleus (the target point). Electrode repositioning resulted in efficient stimulation effects. This case report shows the need to reduce risk factors for intraoperative brain movement and demonstrates the ability of deformation field analysis to quantify this complication.
文摘Fault Ride-Through (FRT) capabilities set up according to the grid codes may affect the performance of related protective elements during fault periods. Therefore, in this paper the coordination between the FRT capability and over-current protection of DFIG Wind Generators in MV networks is investigated. Simulation test cases using MATLAB-Simulink are implemented on a 365-MW wind farm in AL-Zaafarana, Egypt. The simulation results show the influence of the FRT capability on the protective relaying coordination in wind farms, showing that the FRT may work in situations where is were expected not to work, and then disabling the over-current protection, which should have worked in this situation.