In the method provided herein, quantities of fuel are determined during a direct injection of a motor vehicle. In this connection, within one work cycle, test injections are carried out in two cylinders of an internal combustion engine of the motor vehicle during overrun phases, speed oscillations of moved masses of the cylinders are measured and a relative difference in quantity of the fuel quantity of the test injections within one work cycle is determined from the speed oscillations. By evaluating a relative signal between the test injections within one work cycle in the two cylinders, an intrinsic dependence of the drive train of the quantity of fuel signal is compensated.

A smart cup, comprising a cup body (110), a cup cover (120), a light sensor (130) and a main board (140), wherein the cup cover (120) is arranged on the cup body (110), the light sensor (130) is arranged on the cup body (110) and is covered by the cup cover (120), the light sensor (130) can be exposed by opening the cup cover (120), the main board (140) is arranged at the bottom part of the cup body (110) and is isolated from an inner cavity of the cup body (110), the main board (140) is provided with a main processor (141) and a gravitational accelerometer (142), and the light sensor (130) and the gravitational accelerometer (142) are both connected to the main processor (141).

An apparatus for monitoring consumption of flowing substance is provided. The apparatus, connectable to the end of a pipe where fluid is flowing, includes a generator (106) configured to generate electric power from the fluid passing through the generator, sensors (112, 114) to measure the temperature of the fluid and the amount of fluid flowing in the pipe and a processing unit (116). The apparatus detects that fluid starts flowing in the pipe at a first time instant and detects that fluid stops flowing in the pipe at a second time instant and determines the temperature of the fluid and the amount of fluid that flowed through the pipe between the first and the second time instant, stores the determined values and the time elapsed between the first and the second time instants as an entry in a memory (120); and transmits the entry.