4 Computer Graphics and Image Processing (a) Describe the limitations of human vision in terms of: (i) spatial resolution (ii) The underlying bit channel has a capacity of B, a delay and error rate 0. The compression ratio is C < 1. The FEC has rate R < 1 and given an error rate 0 provluminance (iii) colour and explain the implications that each of these limitations has on the design of display devices. [10 marks] (b) In image compression we utilise three different mechanisms to compress pixel data: (i) mapping the pixel values to some other set of values (ii) quantising those values (iii) symbol encoding the resulting values Explain each mechanism, describe the way in which it helps us to compress the image, and describe in what way it affects the visual quality of the resulting (decompressed) image when compared with the original. [10 marks] SECTION B 5 Comparative Programming Languages (a) Outline the main innovations that are in Simula 67 but were not in Algol 60, paying particular attention to Simula Classes. [6 marks] (b) Illustrate how Simula can be used to simulate a small restaurant with six tables, two waiters and small groups of customers arriving at random intervals. You need specify only the classes you would define. Most of the algorithmic details may be omitted. [6 marks] (c) Discuss to what extent Simula has been made redundant by the development of modern object-oriented languages such as Java.

Databases (a) Explain how to describe the structure of a collection of data using entities, attributes and relationships. [6 marks] (b) How would you identify particular instances of data in order to record the information in a database? Illustrate your answer by considering both a relational database maintained using SQL-92 and an ODMG database. [6 marks] (c) A high street bank has just announced a merger with a nationwide building society. You are employed as a consultant to advise on the integration of their client databases. Both institutions use relational databases. Note that the labels depend on the direction moved along the link. Sometimes there may be more than one path to a goal state, and we may want to find the optimal (best possible) path. We can define link costs and path costs for

measuring the cost of going along a particular path, e.g. 8 CST.2014.4.9 8 Security I (a) Windows implements static inheritance for the access-control lists of NTFS files and folders. (i) What does static inheritance mean here and how does it differ from dynamic inheritance? [4 marks] (ii) Five flag bits (ci,oi,np,io,i) in each NTFS access-control entry (ACE) manage how it is inherited. Briefly describe the purpose of each bit. [5 marks] (iii) User mike gives his folder project the following accrcess-control list: project AllowAccess mike: full-access (oi,ci) AllowAccess alice: read-execute (ci,np) AllowAccess bob: read-only (oi) It contains one folder and two text files, none of which have any noninherited access-control entries: project\doc.txt project\src project\src\main.c For each of these three objects, list all inherited access-control entries, showing in parentheses the inheritance-control flag bits that are set (using the same notation as above). [5 marks] In what situations may the bounds be particularly imprecise? What can be done to construct tighter bounds for the system throughput? [1 mark] (iii) What property of those memory patterns would make it most probable that you could successfully train the network to store the maximum number, and why? [3 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.