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In humans, hormone levels, alertness, and core body temperature are synchronized through a 24-hour circadian cycle. Daytime alertness is at its best when sleep/wake cycles are in sync with the circadian cycle. Thus alertness can be easily affected with a distributed work schedule, such as the one to which astronauts are subjected. It has been shown that the human circadian cycle can be delayed or advanced through light stimulus. To ensure optimal alertness, a system is designed to track astronauts' circadian cycles and increase the quality of sleep during missions. Core body temperature can be used as an indicator of the circadian cycle. A computer model with optimum circadian body temperature variations can be compared to an astronaut's body temperatures. Whenever a difference is detected, the astronaut is subjected to a light stimulus to advance or delay the astronaut’s circadian cycle (Mott, 2003). Draw a functional block diagram of the system. Indicate the input and output signals, intermediate signals, and main subsystems.
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Control Systems Engineering
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- During a test on a 5 cylinder four stroke IC diesel engine with a cylinder bore and stroke length of 267 mm and 293 mm respectively, running at 436 rpm, the following results were obtained: Mass on dynamometer mass hanger(arm length=0,823 m)=219,7 kg, indicated mean effective pressure=452 KPa, fuel consumption(with Qnet=39,8 MJ/kg, density=0,944 kg/l)=6 ml/s. Take acceleration due to gravity as 9,81 m per square seconds. Calculate: 1.the indicator power to 2 deimal places(not in kilos unit) 2.the brake thermal efficiency and mechanical efficiency in decimal form to 3 decimal places. 3. the brake power( not in kilos)arrow_forwardDuring testing of single cylinder two-stroke petrol engine following data were obtained. Brake torque = 640 Nm, cylinder diameter 21 cm, speed 350 rpm, stroke length = 28 cm, mean effective pressure = 5.6 bar, oil consumption = 8.16 kg/h, calorific value of the fuel = 42,705 kj/kg. Determine: Srake thermal efficiencyarrow_forwardAn IC engine built to generate power on the basis of constant volume combustion cycle is tested for its performance and the following data were noted. Time taken for 30 cc consumption of fuel by engine=50 seconds, Number of cylinders=1, Mean effective pressure=13 bar, Brake load on dynamometer=6kg, Brake drum radius=22 cm, Engine speed =2308 rpm, Stroke volume = 800 cc, Calorific value of fuel=44000kJ/kg, Specific gravity of fuel=0.7, Density of3standard fluid=1000kg/m , IP=40kW.a) Find if the engine used is a 2-stroke engine or 4-stroke engine?b) What is the percentage conversion of combustion heat to useful output power?c) What percent of the power generated inside the cylinder is transmitted as useful power output?d) If the swept volume is increased by 10%, what would be the change in power generatedinside the cylinder if the engine speed and mean effective pressure is assumed to remain the same as before?arrow_forward
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