GATE CSE 2004
Q31.
How many 8-bit characters can be transmitted per second over a 9600 baud serial communication link using asynchronous mode of transmission with one start bit, eight data bits, two stop bits, and one parity bit?Q32.
Choose the best matching between Group 1 and Group 2 \begin{array}{|l|l|}\hline \textbf{Group-1} & \textbf{Group-2} \\\hline \text{P. Data link layer} & \text{1. Ensures reliable transport of data over a physical point-}\\ & \text{to-point link} \\\hline \text{Q. Network layer} & \text{2. Encodes/decodes data for physical transmission} \\\hline \text{R. Transport layer} & \text{3. Allows end-to-end communication between two }\\ & \text{processes} \\\hline \text{} & \text{4. Routes data from one network node to the next} \\\hline \end{array}Q34.
L1 is a recursively enumerable language over \Sigma. An algorithm A effectively enumerates its words as w1, w2, w3, ... define another language L2 over \SigmaU{#} as {wi # wj : wi, wj \in L1, i \lt j}. Here # is a new symbol. Consider the following assertions. S1 : L1 is recursive implies L2 is recursive S2 : L2 is recursive implies L1 is recursive Which of the following statements is true ?Q35.
Consider the following grammar G: Let Na(w) and Nb(w) denote the number of a's and b's in a string w respectively. The language L(G)\subseteq \{a,b\}^{+} generated by G isQ36.
Let R1(\underline{A},B,(C)) and R2(\underline{D},E) be two relation schema, where the primary keys are shown underlined, and let C be a foreign key in R1 referring to R2 . Suppose there is no violation of the above referential integrity constraint in the corresponding relation instances r1 and r2 . Which one of the following relational algebra expressions would necessarily produce an empty relation?Q37.
Consider the relation Student (\underline{name}, sex, marks), where the primary key is shown underlined, pertaining to students in a class that has at least one boy and one girl. What does the following relational algebra expression produce) (Note: \rho is the rename operator). The condition in join is "(sex=female ^\wedge x=male ^\wedge marks\leq m)"Q38.
Consider the binary relation: S = {(x, y)|y = x + 1 and x, y \in {0, 1, 2,...}} The reflexive transitive closure of S isQ39.
The tightest lower bound on the number of comparisons, in the worst case, for comparison-based sorting is of the order ofQ40.
Consider a program P that consists of two source modules M1 and M2 contained in two different files. If M1 contains a reference to a function defined in M2 the reference will be resolved at