Читать книгу Cyber-physical Systems - Pedro H. J. Nardelli - Страница 35

1 2.1 Residential heating system. There are different ways to heat a house during cold periods as indicated by the USA Energy Department [14]. The idea here is to apply the concepts learned in this chapter to analyze residential heating.Consider an electric heating system connected to the main grid (as any other appliance of your house). Demarcate this system following Example 2.3.Classify the system demarcated in (a) following the examples presented in Section 2.4.During the winter months, the electricity demand in households with electric heating grows as the temperature decreases. Think about a heating system that could function without electricity from the grid. Demarcate this potential heating system and compare it with (a).

2 2.2 Boolean algebra and logic circuits. George Boole, an English mathematician and philosopher from the nineteenth century, proposed in his first book in 1847 a mathematical approach to logic by using mathematical symbols to represent classes of objects and then to manipulate them by mathematics [15]. In another groundbreaking work dating to 1938, Claude Shannon proposed in his Master's thesis a way to materially realize Boolean algebra by circuits [16]. They are represented by truth tables and logical circuits as illustrated in Figure 2.2.Analyze as a system (similar to Exercise 1) the logic gates AND, OR, and NOT, which are the basis of all logic circuits.Figure 2.2 Truth tables and logic gates of AND, OR and NOT operations.Propose a way to materially realize these three logic gates based on (a).Follow the same steps used in (a) to analyze the proposal in (b), identifying the main differences between the conceptual system and its potential material realization.Read Shannon's Master's thesis [16] and discuss the importance of such a discovery.PS The reader is suggested to play with online Boolean algebra calculators (e.g. [17]) as an extra task; a starting point could be the calculation of the truth tables presented in Figure 2.2.