Spring 2002-CS 271     

 

Solutions- Homework 2

 

5.           Yes, it is possible. There are two places where you can place the cache, either locally (with individual CPUs) or globally (with the main memory). The pros and cons of each can be discussed.

 

9.

Number of bits required to represent 64 intensities = 6 (2^ 6 = 64)

Number of colors = 3

Number of pixels per visual field = 10^6

Time resolution is = 100 msec

 

Data rate of human eye = (3*6*10^6)/ (100*10^-3) bits/sec

                                             = 1.8*10^8 bits/sec

 

10.

We need 2 bits to represent the four basic nucleotides.

So, the total information capacity of the human genome is = 2*3*10^9

               = 6*10^9 bits

 

The information capacity of average gene is = (6*10^9)/10^5

= 600000 bits or 60 Kb

 

12.

2^6=64 numbers

               We need minimum N such that 3^N > 64

N = 4

14.

1^st bit checks 1,3, 5,7

2^nd checks 2,3, 6, 7

4^th bit checks 4,5, 6,7

 

0 – 0000000

1 – 1101001

2 – 1101010

3 – 1000011

4 – 1001100

5 – 0100101

6 – 1100110

7 – 0001111

8 – 1110000

9 – 0011001

21.        Outside In is preferred over Inside Out. The track on the out side often holds more data. Thus more data can be accessed in a single rotation at a higher rate. However, this argument seems rather weak to me. Advantages and disadvantages of both can be discussed.

 

26.

Amount of data per second required to be compressed = (720*480*24*30)/8 bits/sec

Amount of data that can be stored in the DVD is = (3.5*2^30)/(133*60) bits/sec

= ((720*480*24*30)/8)/((3.5*2^30)/(13\3*60)) = 3110400/470939.39 = 66:1