Skip to main content

QUINE Mccluskey Tabular Method

QUINE Mccluskey Tabular Method

The K-map method for obtaining simplified Boolean expression is very effective for Functions with less than or equal to four variables. For more than 4-variable logic espresso with less than t becomes any more difficult pumped to draw and solve the K-map. However, there are some general ones that are applicable to functions of a number of variables. One such procedure was originally suggested by Quine and later modified by Mc Cluskey. The Quine-Mc Cluskey method approves so as to minimize the Boolean function in the SOP and POS form. The tabular method is explained as follows.

QUINE Mccluskey Tabular Method

(1) Combination of minterms

(a) All the minterms given in the Boolean function are expressed in the binary representation.

(b) Now all the minterms are arranged in the increasing index. The index is nothing but the number of is in the binary representation of a given minterm.

(c) After arranging all the minterms in various groups of indexes, the "n" index minterms will be compared with all the minterms of the (n + D) index. If two minterms differ by only one variable, then this variable will be eliminated and a dash (-) is placed in that position. Then again we compare (n 1D) hand (n + 2) index, groups. This process is repeated until the comparison is over with all the midterms.

(d) Now in the next stage, further elimination of variables is done from the combination of two minterms to the combination of four minterms. 

(e) This process is repeated until further elimination is not possible.
(e) This process is repeated until further elimination is not possible.

2)  Selection of prime implicants

In the above step, all the possible combinations are grouped and marked with the check sign  Remaining unchecked minterms are called prime implicants. To make the table of prime implicants, all the prime implicants are arranged in the column and all the minterms in "a row".

If they don't care terms are given in the Boolean function, then these terms are not written in the row of the table of prime implicant. Now crosses are placed in the column of minterms which are associated with the prime implicants.

(3) Selection of essential prime implicants

Now we will check the single cross in each column, with primetime implicants the cover minterm with a single cross in each column is called the essential prime implicants. These are shown by a star marked over the prime implicants.

Now the sum of the essential prime implicants is written in the SOP form. If the midterms are not covered by essential prime implicants, then we will consider another prime implicant that covers these midterms.

Read More

Popular posts from this blog

Limitations of Terzaghi Theory

Limitations of Terzaghi Theory The value of the coefficient of consolidation has been assumed to be constant.  The distance d of the drainage path cannot be measured accurately in the field. The thickness of the deposit is generally variable, and an average value has to be estimated.  There is sometimes difficulty 1n locating the drainage face, sometimes thin previous seams that can act as good drainage face are missed in the boring operations. The equation is based on the assumption that the consolidation is one-dimensional. In the field, the consolidation is generally 3-dimensional. The lateral drainage may have a significant effect on the time rate of consolidation. The initial consolidation and secondary consolidation have been neglected. Sometimes these form an important part of the total consolidation. In actual practice, the pressure distribution may be far from linear or uniform. Read More Muller-Breslau principle

Price Guard Wire Method

Price Guard Wire Method Some form of  Price Guard Wire Method  is generally used to eliminate the errors caused by leakage currents over insulation. Fig. 3.14 illustrates the operation of This Method. In fig 3.14(a), a high resistance mounted on a piece of insulating material is measured by the ammeter voltmeter method. The micro-ammeter measures the sum of the current through the resistor (IR) and the current through the leakage path around the resistor. The measured value of resistance computed from the readings indicated on the voltmeter and the microammeter, will not be a true value but will be in error.   Figure 3.14 Application of  guard  circuit for measurement of high resistance In fig, 3.14 (b), the  guard  terminal has been added to the resistance terminal block. The  guard  terminal surrounds the resistance terminal entirely and is connected to the battery side of the micro-ammeter. The leakage current IL now

Negative Booster

Negative booster A negative booster is employed to conform to the regulation that the potential difference between any two points of the rail return shall not exceed 7 V. Two boosters, positive and negative, are used which are mechanically coupled together and driven by a DC motor. The positive booster is connected to the trolley wire (near the generating station) and the negative booster (separately excited) is connected to the track rail.  The 'positive booster' adds voltage to the line while the 'negative booster lowers the potential of the point it is connected to. As we go along the trolley wire away from the generating station/sub-station, the potential drop increases, and the voltage of the trolley wire falls. Since the current returns via the track rail points away from the generating station acquire high potentials. This potential is brought down by the negative boost provided by the negative booster. When the load is sufficiently far aw