Your first line of research is to find out more about this game, especially the style of game play and how the game was constructed. An Internet search on topics such as "Adventure (game)" or "Colossal Cave Adventure" will turn up plenty of information. A good starting point is Wikipedia.

Ultimately, your game will comprise all the following elements, and will form a complete, playable game. (ii) Explain what is meant by a To save effort, the Examiners agree to mark each subject simply by throwing a

fair die once for each candidate and awarding the outcome, a mark in the range 1

to 6. They reason, correctly, that 5 should be the threshold mark for a First since

approximately one-third of the candidates are likely to score 5 or 6.

Noting that 5 is the threshold mark for a First in an individual subject and that

each candidate offers four subjects, the Examiners agree further that 20 marks

(4 5) should be the threshold mark for a First overall in the Examination. i)foreign key in the relational model Transfer (T) transactions which first check whether the source account contains sufficient funds then either abort or continue the transfer from source to destination accounts. Customer x is running a T to transfer 1000 from A to B. Customer y is running a T to transfer 200 from B to A. (a) Discuss the potential for interference between any of these transactions. [7 marks] (b) Demonstrate the effect of concurrency control based on strict two-phase locking in relation to the discussion in (a). [8 marks] (b) Explain how five independent dimensions of visual processing are multiplexed together into the three available spatial dimensions of neural tissue, by the structure of the cubic millimetre hypercolumns in the brain's visual cortex. [5 marks] (c) The retina is often regarded as an image capture device; but it has about 100 million input sensors (photoreceptors) yet only 1 million output fibres (optic nerve axons). What are some implications of this 100-to-1 ratio of input channels to output channels? [4 marks] (a) Describe two quantitative and two qualitative techniques for analysing the usability of a software product. [4 marks] (b) Compare the costs and benefits of the quantitative techniques. [6 marks] (c) Compare the costs and benefits of the qualitative techniques. [6 marks] (d) If restricted to a single one of these techniques when designing a new online banking system, which would you choose and why?

(a) Suppose that women who live beyond the age of 80 outnumber men in the same age group by three to one. How much information, in bits, is gained by learning that a person who lives beyond 80 is male? [2 marks] (b) Consider n discrete random variables, named X1, X2, . . . , Xn, of which Xi has entropy H(Xi), the largest being H(XL). What is the upper bound on the joint entropy H(X1, X2, . . . , Xn) of all these random variables, and under what condition will this upper bound be reached? What is the lower bound on the joint entropy H(X1, X2, . . . , Xn)? [3 marks] (c) If discrete symbols from an alphabet S having entropy H(S) are encoded into blocks of length n symbols, we derive a new alphabet of symbol blocks S n . If the occurrence of symbols is independent, then what is the entropy H(S n ) of this new alphabet of symbol blocks? [2 marks] (d) Consider an asymmetric communication channel whose input source is the binary alphabet X = {0, 1} with probabilities {0.5, 0.5} and whose outputs Y are also this binary alphabet {0, 1}, but with asymmetric error probabilities. Thus an input 0 is flipped with probability , but an input 1 is flipped with probability , giving this channel matrix p (i) Give the probabilities of both outputs, p(Y = 0) and p(Y = 1). [2 marks] (ii) Give all the values of (, ) that would maximise the capacity of this channel, and state what that capacity then would be. [3 marks] (iii) Give all the values of (, ) that would minimise the capacity of this channel, and state what that capacity then would be. [3 marks] (e) For level-1 data caches using a snoopy cache coherency protocol, is a write-back or a write-through policy more likely to be used?

(a) What is the difference between routing and forwarding? [2 marks] (b) Routing algorithms can be either link-state or distance-vector. Define these two terms and explain the trade-offs between them. [6 marks] (c) You are required to design a topology discovery protocol for a network of switching nodes interconnected by links.