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In this work, governing equations of the feed line, cut-off valve, and the starter system are analyzed mathematically and numerically. In the mathematical solution, the stability of the valve system is considered using the Laplace transform along with the linearization of the equations of the system. According to parameter design of the feed pipe–valve system, the system demonstrates the stable behavior in the effective parameter of the valve system on the basis of the Nyquist and Bode stability criterion. In the numerical solution, the steady state behavior of the cut-off valve is simulated during the cut-command. Then the rate of the pressure variation, mass flow rate through of the valve, gas pressure of the starter system, and the upstream pressure of the valve (water hammer) are considered based on the valve's poppet motion. The comparison of the simulation results with the experimental data depicts only 13 percent error in the mass flow rate through of the valve. In the last time of the closing valve, there is no variation in the mass flow rate in the valve due to the excessive loss factor of the valve when the valve approximately is closed. The results show that the closure of the cutoff valve shall be provided in accordance with allowable maximum pressure of the hydraulic shock on the established

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In this paper the conventional structure of dual-axis sun tracker is modified based on new mechanical and electrical detectors which are proposed to reduce both the angular error and power consumption. Automatic adjustment of the azimuth, latitude and altitude angle for the photovoltaic panels improves the performance of converting solar energy to the electrical energy, throughout all the seasons. In other words, both the north-worth and east-west angular error is continuously minimized until that the panel’s surface is solarized with the maximum energy. Post-Fabrication results show that the proposed control circuit and two actuators consume the average power of less than 10mWatt alongside the 13-hour of a summer day. The external power source is no longer required because the received power is saved in a battery in order to provide the power of the control circuit. The ratio of the required energy to the saved energy is optimized to around 0.13%. Measurement results confirm that the total Watt-hour during a summer day is improved around 60 percent in comparison to the case that a fixed panel is used. Design of the mechanical objects are performed using CATIA software such that endure up to 1200Watt panel array.