"There is a growing interdependence between a firm's ability to use information technology and its ability to implement corporate strategies and achieve corporate goals."

"To fully understand information systems, you must understand the broader organization, management, and information technology dimensions of systems and their power to provide solutions to challenges and problems in the business environment ."Discuss whether or not the case study provides empirical support for the above two claims.

Which specific business processes and/or management activities in the "business information value chain" like supply chain management, enterprise management, customer management, knowledge management, planning, coordinating, controlling and modelling and decision making comprise the focus of the IT efforts in each of the three firms/business units (data collection and storage, transformation into business system and dissemination)?

For each firm/business unit, do the business processes and management activities you identified above seem to be well supported by its information processing activities? Explain your reasoning.

Which "strategic business objectives" of information systems are evident in each case study? Discuss.

What kinds of ethical issues are evident in the case study, even if not mentioned explicitly? Discuss. Ethical issues are Information rights and obligations What information rights do individuals and organizations possess with respect to themselves? What can they protect? Property rights and obligations How will traditional intellectual property rights be protected in a digital society in which tracing and accounting for owner- ship are difficult, and ignoring such property rights is so easy? Accountability and control Who can and will be held accountable and liable for the harm done to individual and collective information and property rights? System quality What standards of data and system quality should we demand to protect individual rights and the safety of society? Quality of life What values should be preserved in an information- and knowledge-based society? Which institutions should we protect from violation? Which cultural values and practices does the new information technology support? no half work answer all

(a) Describe the possible market failures affecting anti-virus software firms in the late 1980s and early 1990s, when viruses were a new threat to computer systems and dozens of firms started up to offer anti-virus software. [5 marks] (b) Describe how the incentives facing anti-virus software firms had changed 10 years later once the industry had consolidated into a handful of large firms. How might this affect attacker behaviour? [5 marks] (c) How will the incentives have changed in recent years with the spread of online banking and crypto currencies? [5 marks] (d) How do you expect the anti-virus industry to change as computing shifts from PCs and laptops to phones and tablets? What about the impact of systems embedded in durable consumer goods such as cars? [5 marks] 4 CST1.2018.7.5 3 Formal Models of Language Consider the following grammar: S NP VP NP N S NP N VP V N VP V N {Alice, cats} V {saw, grinned} (a) The grammar can be used to generate the following sentences: (i) Alice saw cats (ii) Cats Alice saw grinned Draw derivation trees for both of these sentences. [2 marks] (b) What is the longest sentence that can be generated by the grammar? Describe this sentence. [2 marks] (c) Is the language generated by the grammar a regular language? Provide a proof for your answer. [8 marks] (d) A psycho-linguistic experiment shows that, by the 2nd word in the sentence, Part (a)(ii) is harder to process than the sentence Part (a)(i). Yngve hypothesised that a speaker's short-term memory functions as a stack. Explain how this hypothesis might account for the experimental results by drawing the stack arising from a top-down parse of the two sentences. [4 marks] (e) How might the sentence in Part (a)(ii) be altered so that it has the same meaning but is easier to process? Explain your reasoning. [4 marks] 5 (TURN OVER) CST1.2018.7.6 4 Further Graphics (a) Here are two methods for implementing a cube using signed distance fields: float methodOne(vec3 p) { return max(max(abs(p.x), abs(p.y)), abs(p.z)) - 1; } float methodTwo(vec3 p) { vec3 d = abs(p) - vec3(1); return min(max(d.x, max(d.y, d.z)), 0.0) + length(max(d, 0.0)); } One is preferable to the other for producing better images faster. Which one, and why? [4 marks] (b) Complete the code below to implement the signed distance field function for a finite line segment with hemispherical end-caps (Figure 1) of arbitrary start point, end point, and radius. [4 marks] float lineSegment(vec3 p, vec3 start, vec3 end, float radius) { // [YOUR CODE HERE] } float getSdf(vec3 p) { return lineSegment( p, vec3(-PI, 0, 0), vec3(PI, 0, 0), 0.5); } (c) Implement a version of getSdf() that doubles the height of your line segment and translates it by 0.5 along the Z axis, to be centred at (0, 0, 0.5) (Figure 2). [4 marks] (d) Implement a version of getSdf() that warps the original line segment into a sine wave sin(X) (Figure 3). [4 marks] (e) Modify getSdf() to render the sine wave model subtracted from the taller model (Figure 4). [4 marks] 6 CST1.2018.7.7 Figure 1 Figure 2 Figure 3 Figure 4 Figure 1: A finite cylinder of radius 0.5 centred at (0, 0, 0) with hemispherical end-caps, starting at (, 0, 0) and ending at (, 0, 0). Figure 2: The original finite cylinder has been enlarged to double its height on the Y axis and has been translated in Z so that it is now centred at (0, 0, 0.5). Figure 3: The original finite cylinder has been warped with a sine wave. Its centre remains at (0, 0, 0) and its endpoints remain centred around (+/, 0, 0), but in between its central axis falls to Y = 1 and rises to Y = 1. Figure 4: The sine wave has been subtracted from the double-height cylinder. (Note: Ground plane shown at Y = 1 for illustration purposes only) 7 (TURN OVER) CST1.2018.7.8 5 Further Graphics (a) Write a GLSL function dartboard() which takes as input a texture co-ordinate texCoord which ranges from (0, 0) (1, 1), and returns the colours of the procedural texture for a black-and-white dartboard pattern of 16 squares around and 8 squares in radius (see figure below). The background behind the dartboard is gray. vec3 dartboard(vec2 texCoord) { // [YOUR CODE HERE] } [6 marks] (b) What is . . . (i) the formula for the face angle (F, vi) of face F at vertex vi of a closed manifold? [2 marks] (ii) the formula for the angle deficit AD(v) of vertex v and its surrounding set of faces {F}? [2 marks] (iii) the formula for the Poincare Formula of a surface with genus g and Euler characteristic ? [2 marks] (iv) the formula for Descartes' Theorem of Total Angle Deficit? [2 marks] (c) Consider a closed manifold surface with total angle deficit 4. (i) If your hypothetical surface has 20 vertices and 20 faces then how many edges must it have? [2 marks] (ii) Sketch a picture of your surface. [4 marks] 8 CST1.2018.7.9 6 Further HCI (a) Explain in general how the actions that a user takes are related to the user's goals. Your answer should make reference to the function of perception, and to the nature of the cognitive processing that must occur. [8 marks] (b) Describe a class of problems for which it is not possible to formulate goals. Give a specific example of a problem in this class, and with reference to that example, explain how it illustrates two significant attributes of the class. [6 marks] (c) If an interactive system has several alternative models to describe the user's goal, how can Bayes' theorem be used to improve the system usability?

(a) State precisely what it means for a language (i) to be co-NP-complete, (ii) to be in NL and (iii) to be in PSPACE. [6 marks] (b) Consider the following two decision problems. Problem 1: Given an undirected graph G = (V, E) with |V | even, does G contain a clique with at least |V |/2 vertices? Problem 2: Given an undirected graph G = (V, E), does G contain a clique with at least |V | 3 vertices? (i) Which of the two problems is in P and which one is NPcomplete? [2 marks] (ii) For the problem in P, describe a polynomial-time algorithm. [4 marks] (iii) For the other problem, prove that it is NP-complete. [8 marks] 3 (TURN OVER) CST.2014.6.4 3 Computation Theory (a) Explain how to code register machine programs P as numbers pPq N so that each e N can be decoded to a unique register machine program prog(e). [10 marks] (b) Find a number e1 N for which prog(e1) is a register machine program for computing the function one N N with one(x) = 1 for all x N. [2 marks] (c) Why is it important for the theory of computation that the functions involved in the coding and decoding given in part (a) are themselves register machine computable? (You are not required to prove that they are computable.) [2 marks] (d) Define what it means for a set of numbers S N to be register machine decidable. [2 marks] (e) Let e N*N denote the partial function of one argument computed by the register machine with program prog(e). Prove that {e N | e = one} is register machine undecidable (where one is the function mentioned in part (b)). State carefully any standard results that you use in your proof. [4 marks] 4 CST.2014.6.5 4 Computation Theory (a) Give the recursion equations for the function n (f, g) N n+1 N defined by primitive recursion from functions f N n N and g N n+2 N. [2 marks] (b) Define the class PRIM of primitive recursive functions, giving exact definitions for all the functions and operations you use. [5 marks] (c) Show that the addition function add(x, y) = x + y is in PRIM. [2 marks] (d) Give an example of a function N 2 N that is not in PRIM. [3 marks] (e) The Fibonacci function fib N N satisfies fib(0) = 0, fib(1) = 1 and fib(x + 2) = fib(x) + fib(x + 1) for all x N. (i) Assuming the existence of primitive recursive functions pair N 2 N, fst N N and snd N N satisfying for all x, y N fst(pair (x, y)) = x snd(pair (x, y)) = y prove by mathematical induction that any function g N N satisfying g(0) = pair (0, 1) g(x + 1) = pair (snd(g(x)), fst(g(x)) + snd(g(x))) for all x N, also satisfies x N(fst(g(x)) = fib(x) snd(g(x)) = fib(x + 1)). [4 marks] (ii) Deduce that the Fibonacci function fib is in PRIM and Proof (a) Proof methods for propositional logic include the sequent calculus, DPLL and BDDs. Describe briefly each of these methods. State, with reasons, which method is to be preferred for a problem that makes heavy use of the and symbols. (Note that denotes exclusive or.) [7 marks] (b) Describe briefly the procedure for constructing a BDD, illustrating your answer using the formula ((P Q) R) (P (Q R)). [7 marks] (c) Consider the following set of n + 1 propositional formulas, where n 0: Pi Pi+1 (for i = 1, . . . , n) P1 Pn+1 Describe a possible execution of the DPLL procedure to determine whether this set is satisfiable or not. [6 marks] 6 CST.2014.6.7 6 Logic and Proof (a) Describe briefly the concept of a decision procedure, listing at least three separate examples of decidable theories. [4 marks] (b) Outline the basic ideas behind Fourier-Motzkin variable elimination, demonstrating them with reference to the following small set of constraints: x + 2y 10 x + z 5 y 3 z 2 0 [6 marks] (c) Call a clause positive if it consists of positive literals only. Negative selection is a refinement of resolution where two clauses can be resolved only if one of them is positive; if a clause contains any negative literals, then only one of those may be resolved with a literal in another (necessarily positive) clause. Negative selection reduces the number of combinations of literals to be compared, thereby improving performance. Consider the following set of clauses: {R(0), R(1)} {P(h(z)), R(z)} {P(x), R(y)}. With negative selection, the first resolution step must involve {R(0), R(1)}, as no other positive clauses are available at the start. (i) If a set of clauses includes no positive clauses, can it be unsatisfiable? Justify your answer. [3 marks] (ii) Use resolution with negative selection to derive a contradiction from the clauses above.