Software Design and Development 2016 HSC exam pack (archive)

Candidates showed strength in these areas

• identifying the collaborative environment that a network can provide during software development (Q21)
• outlining varying factors that can affect response times in a computer system (Q22)
• designing a user interface, showing understanding of screen elements, for example, using a radio button for gender with annotations justifying the appropriateness of the screen element (Q23)
• correctly identifying errors, including that the equalities needed to be changed to inequalities (line 4), and that there was an error in not comparing C to B (line 7) (Q24a)
• providing three correct lines in the algorithm (Q24b)
• demonstrating an understanding of the nature and purpose of logbooks (25a)
• identifying reasons why project managers need good communications skills (Q25c)
• demonstrating knowledge of a variety of data types, including floating point/real, integers and strings (Q26a)
• identifying and outlining suggestions for how the algorithm could be improved, including suggestions commonly related to intrinsic documentation, indentation, comments and capitalisation (Q26b)
• describing, in general terms, the role of debugging in locating errors in code (Q27)
• recognising all of ’John’s‘ data (Q28)
• describing the applicability of the ‘Agile’ approach (Q29a)
• demonstrating knowledge of the DFD symbols and how they apply to a given scenario (Q29b)
• identifying and describing a variety of social issues (Q29c)
• drawing links between sorting and searching methods and various project management tools (25b)
• recognising, for example, data needs to be sorted for a binary search, and factors which influence decisions about the applicability of these methods (Q30)
• including the given code in the solution and correctly modifying the references in the array (Q31)
• demonstrating some knowledge of EBNF and recognising that <condition> and <statement> needed repeating (Q32)
• identifying an appropriate display or print statement (Q33).

Candidates need to improve in these areas:

• making clear the connection between the factor and response time, such as, a faster CPU means more instructions can be processed in less time, minimising response time (Q22)
• providing clear justifications of the elements used in the screen designs (Q23)
• demonstrating an understanding of what input means, and that it changes the values of the variables, thus not inducing an infinite loop (Q24a)
• demonstrating an understanding of how the REPEAT UNTIL control structure operates, and that it does not apply to the statement preceding it (Q24a)
• clearly setting out desk-checks, for example, tracing through the supplied test data and including a column for the output, could have eliminated common errors (Q24b)
• distinguishing between techniques that are part of the development process and those that specifically relate to project management (Q25b)
• differentiating between management tools and techniques (Q25b)
• providing specific examples of where communication occurs between the various stakeholders in developing a piece of software (Q25c)
• describing how a debugging technique is used to locate an error for a specific scenario (Q27)
• understanding that arrays only support the one data type (Q28)
• relating the response to the given scenario (Q29a)
• writing meaningful labels for all DFD elements, for example, labelling a data flow as ’search query‘ (Q29b)
• linking factors such as how often the data is updated to the features of sorts and searches (Q30)
• correctly understanding all the requirements of the solution (Q31)
• correctly using terminal elements from their EBNF (Q32)
• showing the correct syntax for opening and closing a sequential file (Q33)
• identifying an appropriate way to terminate a loop using either an EOF or sentinel value (Q33).

Candidates showed strength in these areas

• recognising features of expert systems, including the use of the logic paradigm and the replacement of a human expert (Q34a)
• identifying characteristics of both object orientated and logic paradigms that relate to the scenario (Q34b)
• producing the syntax for a new fact that extends the logic code (Q34ci)
• recognising the appropriate facts, those involving dance, related to the query (Q34cii)
• recognising a feature of an attribute in object oriented code (Q34di)
• identifying and assigning values to attributes (Q34dii)
• providing a method that could solve the problem (Q34diii)
• demonstrating knowledge of differences in character representations using ASCII and Unicode (Q35a)
• demonstrating the ability to shift and subtract using long division including using the addition of 2’s complement numbers (Q35b)
• demonstrating the ability to construct a truth table for the given gates and draw conclusions from the relevant rows related to the question (Q35ci)
• analysing the problem table, either with a truth table or simplifying the Boolean logic prior to attempting to draw a circuit (Q35cii)
• identifying possible content in the header and trailer (Q35di)
• interpreting the data block, for example, identifying the additional requirement for bold and italics (Q35dii)
• recognising that there were two effects of not having the 1B in that part of the stream, including, what would not happen (flashing) and what would replace it (Q35diii).

Candidates need to improve in these areas:

• identifying the essential features of an expert system, such as the ability to reach a conclusion based upon the data entered (Q34a)
• explaining how the strengths and features of object oriented and logic paradigms could be used in the scenario (Q34b)
• producing the syntax for multiple facts and rules required to extend the logic code (Q34ci)
• describing how chaining works to arrive at a result, through checking if the facts and rules match the goal of the query (Q34cii)
• explaining how inheritance is used in object oriented programming to simplify the code and eliminate duplication of attributes (Q34di)
• writing the code to instantiate an object and assign values to all its attributes (Q34dii)
• demonstrating knowledge of how to write a constructor method used during instantiation, including the use of a parameter to assign the id attribute (Q34diii)
• understanding that for Unicode to store a greater range of characters it will need more storage (Q35a)
• understanding of place value in binary arithmetic in order to come to a correct solution (Q35b)
• demonstrating knowledge of the range of gates in the syllabus and course specifications document, and how inputs would affect their outputs, for example, after a correct truth table, there is a needed to analyse the relevant lines to ‘show’ the output of Z was always 1 (Q35ci)
• taking all input conditions and their required outputs into consideration when designing the circuit, and then testing the circuit after the design is done (Q35cii)
• demonstrating knowledge of the possible contents of headers and trailers in a data stream and how this differs to the data block (Q35di)
• using all of the information provided, in particular 1B, as a control character (Q35dii)
• demonstrating knowledge of how control characters affect a data block (Q35diii).