IPT 2009 End of Year Exam Study Guide
How to use this study guide This guide needs to be used with the course text, notes from class and the internet Each bullet point needs: – to be researched fully – Written notes (no cutting and pasting) – Include images – Definition – Example of its use
Information systems in context diagrams the environment – everything that influences and is influenced by the information system the purpose – a statement identifying who the information system is for and what it needs to achieve the information system – a set of information processes requiring participants, data/information and information technology built to satisfy a purpose information processes – computer based and non-computer based activities information technology – hardware and software used in information processes data – the raw material used by information processes information – the output displayed by an information system user – a person who views or uses the information output from an information system participant – a special class of user who carries out the information processes within an information system
Information processes Collecting – the process by which data is entered into or captured by a computer system, including: deciding what data is required how it is sourced how it is encoded for entry into the system Organising – the process by which data is structured into a form appropriate for the use of other information processes such as the format in which data will be represented Analysing – the process by which data is interpreted, transforming it into information Storing and Retrieving – the process by which data and information is saved and accessed later Processing – a procedure that manipulates data and information Transmitting and Receiving – the process that sends and receives data and information within and beyond information systems Displaying – the process that controls the format of information presented to the participant or user
Barcode scanners Barcodes are produced and being read. It is operate by reflecting light off the barcode image; light reflects well off white and not very well off black. This digital data may be analysed, organised and processed into numbers or text or it may remain as image data in the form of bitmaps. CCD Barcode Scanners charges coupled devices contain one or more rows of photocells built into a single microchip. There three types of scanners which is LED wand, CCD barcode scanners and multi- directional laser. The reflected light form the LED is measured using a single photocells. Lasers are high intensity beams of light and as such they can be directed very precisely.
Device drivers A device driver simplifies programming by acting as a translator between a hardware device and the applications or operating systems that use it. Programmers can write the higher-level application code independently of whatever specific hardware device it will ultimately control, because code and device can interface in a standard way, regardless of the software superstructure or of underlying hardware. Every version of a device, such as a printer, requires its own hardware-specific specialized commands. In contrast, most applications utilize devices (such as a file to a printer) by means of high-level device-generic commands such as PRINTLN (print a line). The device- driver accepts these generic high-level commands and breaks them into a series of low-level device-specific commands as required by the device being driven. Furthermore, drivers can provide a level of security as they can run in kernel-mode, thereby protecting the operating system from applications running in user-mode.
Random access memory (RAM) RAM holds both the software and the data used by CPU during processing. As secondary storage is many thousands of times slower than RAM, a noticeable drop in performance will certainly result.A retrieving process that would take seconds using RAM will take hours using a typical hard disk. The speed at which data held in RAM can be accessed is important for analysing processed. Different types of RAM are able to operate at different speeds.
System clock The system clock is located on the motherboard. The signal generated is transmitted along a wire within the control bus and hence is available to all devices connected to the system bus.The clock signal continuously alternated between high (1) and low (0) at a constant pace. The transition form high to low and in some instances also from low to high are used to synchronise the transfer of data and also the operation of all components connected to the system bus.
Data storage types Primary Storage : Basically, primary storage is the memory part of the computer itself. Primary storage includes the Random Access Memory (RAM) and Read Only Memory (ROM). Secondary Storage Hard disks, magnetic tapes and all other data storage devices are included in the secondary storage. They are external to the processor and are used to increase the storage capacity of the computer. The secondary storage is non-volatile and can retain information even after the computer is switched off. Tertiary Storage Tertiary data storage is the third data storage out of the three types of data storage. The tertiary devices includes the storage devices that are connected to the computer in the form of removable mass storage devices. Tertiary storage is often used to store those files that are rarely accessed by the computer user.
Streaming data Streaming media are multimedia that are constantly received by, and normally presented to, an end-user while being delivered by a streaming provider. Data is received into one end of the buffer and removed from the other end for decompression and subsequent display.
Display devices (LCD’s)
Digital to analog conversion (DAC) A DAC converts an abstract finite-precision number (usually a fixed-point binary number) into a concrete physical quantity. In particular, DACs are often used to convert finite-precision time series data to a continually- varying physical signal. A typical DAC converts the abstract numbers into a concrete sequence of impulses that are then processed by a reconstruction filter using some form of interpolation to fill in data between the impulses.
Social and ethical issues Social and ethical issues arising from the processing of information, including: privacy of the individual security of data and information accuracy of data and information data quality changing nature of work appropriate information use health and safety copyright laws
Vector graphics and Bitmaps A bitmap graphic (you may occasionally hear “raster” graphic) is basically a large grid - think of a huge checkerboard, or a screen door, or any grid with a lot of little squares. In regards to this discussion, a vector graphic is one in which the shape or path of a line is defined by a bit of math. Vector graphics are basically points connected by lines of various shapes, filled with solid or gradient colors.
Volatile/non-volatile storage devices
Modulation Modulation is the process of varying one waveform in relation to another waveform. In telecommunications, modulation is used to convey a message, or a musician may modulate the tone from a musical instrument by varying its volume, timing and pitch.
Audio processing Audio processing covers many diverse fields, all involved in presenting sound to human listeners. Three areas are prominent: (1) high fidelity music reproduction, such as in audio compact discs, (2) voice telecommunications, another name for telephone networks, and (3) synthetic speech, where computers generate and recognize human voice patterns.
Sampling Samples are joined to approximate the orginal sound wave.
File formats A file format is a particular way that information is encoded for storage in a computer file. Some file formats are designed to store very particular sorts of data: the JPEG format, for example, is designed only to store static photographic images. Many file formats, including some of the most well-known file formats, have a published specification document (often with a reference implementation) that describes exactly how the data is to be encoded, and which can be used to determine whether or not a particular program treats a particular file format correctly.
Data collection devices (flatbed scanners)
Hardware (soundcard processing)
Synchronous asynchronous
Communication Communication is a process of transferring information from one entity to another. Communication processes are sign- mediated interactions between at least two agents which share a repertoire of signs and semiotic rules. Communication is commonly defined as "the imparting or interchange of thoughts, opinions, or information by speech, writing, or signs".
Electronic mail applications
Data storage (backup)
Context diagrams Context Diagrams : Context diagrams are used to represent an overview of the entire information systems. The system is shown as a single process along with the inputs and outputs. The external entities are connected to the single process by data flow arrows. Each element represented is labelled. A context diagram does not show data stores and internal processes. The example below is a context diagram that represents a video borrowing process.
Optical character recognition (OCR)
Website layout, navigation and design
Team management Team management refers to techniques, processes and tools for organizing and coordinating a group of individuals working towards a common goal—i.e. a team. Several well-known approaches to team management have come out of academic work. Examples include the Belbin Team Inventory by Meredith Belbin, a method to identify the different types of personalities within teams, and Ken Blanchard's description of "High Performing Teams".