Consider a restaurant recommendation application (Live2Eat),…
Consider a restaurant recommendation application (Live2Eat), which shows you nearby restaurants for a given location. Assume that Live2Eat automatically updates the location as the user moves, and that it also updates the nearby restaurants. It has **two options** for obtaining the location information. The first option: by using GPS, which is more accurate. The second option: by using the mobile tower-based cellular network, which is far less accurate. Suppose that there is a Live2Eat user who is driving down a street, and the GPS signal is lost at time t = 0. Also suppose that the average speed of traffic is 15 km/h (9.32 mph). The error in GPS localization is 50 m (0.031 miles), while the error in mobile tower-based localization is 100 m (0.062 miles). Consider that location information is requested by Live2Eat every minute. When should you switch from GPS to cellular?
Read DetailsImagine a scenario where Boeing designed a pilot monitoring…
Imagine a scenario where Boeing designed a pilot monitoring system that deploys in response to a failing MCAS system. If an MCAS system is engaged and the pilot is detected to be stressed, MCAS will automatically disengage. In this system, consider a brain mobile interface application where the pilot wears a Neurosky headset that senses brain signals (EEG) at 400 Hz. Each brain data point is a 32-bit floating point number. The brain signal is collected by a central controller in the plane and sent to a server, where complex machine learning algorithms are employed to determine the stress level of the pilot. Additionally, the aircraft is equipped with sensors, such as the AoA, pitch monitoring, and other relevant sensors. The data rate from the AoA is 5 kbps, and the data rate from the other relevant sensors is 300 kbps. Using the data from these sensors, the MCAS disable system attempts to predict MCAS failures. If the system detects that the pilot is stressed and an MCAS failure is predicted, the auto-disable facility should disable MCAS. The auto-disable feature only has 5 seconds to make a decision after collecting 5 seconds worth of data. There are two options for performing all of the related computation: (a) use a GPU server at the control center, or (b) use a fog server that is onboard the aircraft. The GPU server upload speed is 1 Mbps, whereas the fog server upload speed is 5 Mbps. However, the computation speed of the GPU server is 1500 kbps (in other words, it can finish the computation on 1500 kb of data in 1 second), whereas the fog server has a computational speed of 200 kbps. Suppose the failure rate of the GPU server is 0.2. This means that 20% of the time the GPU will send a failure message back to the auto-disable system. When this occurs, the system must transfer all of the information to the GPU server again and redo the computation. The time taken to communicate that a failure has occurred is 500 milliseconds. What is the average total time taken for both communication and computation to be performed in the GPU server, in milliseconds?
Read DetailsImagine a scenario where Boeing designed a pilot monitoring…
Imagine a scenario where Boeing designed a pilot monitoring system that deploys in response to a failing MCAS system. If an MCAS system is engaged and the pilot is detected to be stressed, MCAS will automatically disengage. In this system, consider a brain mobile interface application where the pilot wears a Neurosky headset that senses brain signals (EEG) at 400 Hz. Each brain data point is a 32-bit floating point number. The brain signal is collected by a central controller in the plane and sent to a server, where complex machine learning algorithms are employed to determine the stress level of the pilot. Additionally, the aircraft is equipped with sensors, such as the AoA, pitch monitoring, and other relevant sensors. The data rate from the AoA is 5 kbps, and the data rate from the other relevant sensors is 300 kbps. Using the data from these sensors, the MCAS disable system attempts to predict MCAS failures. If the system detects that the pilot is stressed and an MCAS failure is predicted, the auto-disable facility should disable MCAS. The auto-disable feature only has 5 seconds to make a decision after collecting 5 seconds worth of data. There are two options for performing all of the related computation: (a) use a GPU server at the control center, or (b) use a fog server that is onboard the aircraft. The GPU server upload speed is 1 Mbps, whereas the fog server upload speed is 5 Mbps. However, the computation speed of the GPU server is 1500 kbps (in other words, it can finish the computation on 1500 kb of data in 1 second), whereas the fog server has a computational speed of 200 kbps. What is the communication time for the GPU server in seconds?
Read Details