Information skills and system Essay

A system is a collection of devices that works together to archive a particular proposition purpose. Examples include transport system, school system, digestive system etc. A system can be represented as followingInput component part to processing of systemControl commanding processing unitProcessing transforming input to outputStorage where content can be put forward and retrieved for afterwards use.Output the outcome of this systemAn information system is a system that accepts data (raw material) as input and information (organised data) as output. Examples include a computer, searchable databases etc. An information system is faten belowPurpose The use and function of the systemInformation process The process of converting data into informationParticipants All mint who ar involved in the systemInformation technology The equipment and instruction used.Data and information Data, the input (raw material), and information, the output (processed data).The information p rocess Collecting assembly of data from real world. Eg entering details Organising preparing data for the use of other processes. Eg arranging data into tables Analysing converting data into useful information, commonly more digestible. Eg creating a graph from tables of data Saving and retrieving storing data/information for later uses. Eg saving document onto hard drive. Processing making flip-flop in data/information, including updating, correction of erroneous belief etc. eg spell check Transmitting and receiving exchanging data/information with other information systems, near of remote. Eg internet, e-mailing Displaying presentation of information. Usually user-friendly, easy to understand. Eg projecting graph onto disguiseDigital representation of dataAll data is in a central process unit is processed as electrical currents. Data is usually converted into binary decimals, consisting only 1 or 0, where 1 represents on and 0 represents off. Different data types be converted polarly, and this will be discussed in tools for organising later.Binary digitsDecimalBinaryEach digit in a binary decimal can only be 1 or 0. To convert from decimal x to binary divide x by highest practicable post of 2, then divide left over by highest possible power of 2, repeat until 1 or 0 is left. Eg 25 = 24 x 1 + 23 x 1 + 22 x 0 + 21 x 0 + 20 x 1 in that locationfore 25 decimal = 11001 in binary. To convert binary into decimal you do the reverse. Eg 101011 in decimal is 25 x 1 + 24 x 0 + 23 x 1 + 22 x 0 + 21 x 1 + 20 x 1 = 32 + 0 + 8 + 0 + 2 + 1 = 43ASCII code systemThe ASCII (American Standard code for Information Interchange) system uses binary decimals to represent different characters. Each digit takes up repositing of 1 bit it takes 8 digits i.e. 8 bits i.e. 1byte to form a character. 1024bytes (210 bytes) = 1KB 1024KB (220 bytes) = 1MB 1024MB (230 bytes) = 1GB etc different combinations of any 8 bit forms a character. ASCII includes most if not all symbo ls, including intangible ones eg Del, Space etcHexadecimalsHexadecimal is used in computing when there be too many digits for binary decimal. Eg 255 have 8 digits in binary but only 2 in hexadecimal. It is used for large cherish numbers such as in the case of html colour panels.Hexadecimals ar 16 digit based 10 15 is replaced with A F respectively. To convert decimal to hexadecimal or hexadecimal to decimal uses the aforementioned(prenominal) method as binary diversity, but 16 based.Eg converting 1980 into hexadecimal1980 = 162 x 7 + 161 x 11 + 160 x 12Therefore 1980 in hexadecimal is 7BCEg converting 15FA into decimal163 x 1 + 162 x 5 + 161 x 15 + 160 x 10= 4096 + 1280 + 240 + 10= 5626Therefore 15FA in decimal is 5626.Social and Ethical issuesHealth of human body can be allude through use of information systems. The study of human body and technology is referred as ergonomics. The following are a few health problems the can nobble form the use of information systemTools f or information process CollectingThe collecting process involves deciding what to collect, where to collect form and how to collect.Hardware for collecting different data textbook keyboard, text scanner, voice recognitionNumbers bar code canvassers, data loggers, keyboardImages scanner, web camVideo video recorders, digital camerasAudio micro-phone, packet for collecting different dataText Microsoft wordNumbers Microsoft excelImages scanner softwareVideo windows media playerAudio Sound recorderOrganizingText as explained before texts are converted into binary decimals to be processed by other processes, e.g. displaying, analysing etc. Examples of file types word document, HTML, PDFNumbers Like text, to each one numerical number can be converted into a binary number. Common file type excel, word documentImages An image is an electronic reproduction of a picture, photo, scanned document etc for display on screen. All images are made of pixels, which are the littlerest controllable display element on most screens. There are two types of imagesBitmapped each pixel is treated individually and represents bits in memory. Their size, colour, tone etc is stored and therefore takes up large amount of memory. The most common bitmapped file types are BMP (high quality images), JPEG (less memory, lossy compression method) and GIF (maximum 256 colours for cartoons, lossless compression by less colour and smaller size).Vector end points containing information about the profligate (thickness, colour, gradient etc) common type of file is PNG, but not supported by early versions of internet explorer.Audio Series of sound measurements. Digital samples are created from real sound waves. The higher frequency of taking samples and the more accurate they are, the better the quality, but the larger the file. Common file types are MIDI and waveform (MP3, MP4 etc).Video A series of still images recorded at high speed, usually a long with audio. Hugh in file size. Co mmon file types include frolicsome GIF, MPEG, Flash etc. data is organized using key frames, one for each image that forms a video/animation when playedAnalyzingAn example of analyzing data is creating a graph in a spread sheet. Charts and graphs are the most popular ways of analyzing data. They show relationships, trends and comparisons at a glance. The impact (use of colours and symbols to play up attention to important data), speed (obvious) and simplicity (easily understood) made it popular. E.g. software excel, calculatorSaving and retrievingSaving and retrieving is important because it allows edited data to be stored and edited later on. Most information systems have a primary storage and a secondary storage.Primary storage is used to store data/information that involve to be instantly accessible to the CPU. It uses silicon chips on the motherboard to store.RAM random access memory, where frequently used data/information and instructions are stored. When the power is cut of f everything in RAM disappears. Data are accessed directly without going through other things.Cache is another example of primary storage. It has the same functions are RAM, but is temporary storage for quick access.ROM read only memory, permanent memory where instructions are stored. These instructions are not to be edited or it may distract the processing of the computer. These instructions are applied when booting the computer.Secondary storages are usually portable.Magnetic tape long thin plastic coated with thin layer of magnetic metal. Magnetic tape can store large amount of data for a flash price and little space. However it uses sequential memory access, which takes a lot of time. e.g. video tape. Good for back up.Magnetic disk works the same as magnetic tape, but with a circular piece of plastic/metal. E.g. hard disk / floppy disk. Uses random memory access.Optical media uses laser technology to read and write on CD, CDR or CDRE. Written with high power laser to create lot s of tiny holes on disk.Flash memory is erasable memory chips e.g. USB, SD card, memory stick etc.ProcessingExamples of processing software audio editing programmes, movie maker, video editorsTransmitting and receivingBuses and ports are used for transmitting and receiving. Buses are connections between CPU and other parts. Ports are sockets that allow an external device to be installed. E.g. e-mail is transmitting and receiving mails.DisplayingPrinter, monitor speakers etc. most monitors are displayed in pixels. Number of pixels on the screen can be adjusted.Planning, deigning and implementationUnderstanding the problemThis is the first stage of developing a system. It involves identifying the problem that needs to be solved and determining the requirements of the bracing system through surveys, interviews, analysing existing system, investigation, research etc. Draw up a project plan, specifying who, what how, when consisting grant charts, schedules, dataflow diagrams, journals, plans etc. fashioning decisionsDetermine the feasibility (is it possible) of this new system, analysing potential solutions and makes a recommendation. A feasibility study shows nature of problem and overview of existing system identifying problem outline constraints (economical, court vs. benefit technical, technology requirements and demands schedule, time wise organisational, fitting the goal of organization) restates aim of new system in detail analyse data collected arouse solution no change, new system, investigate etcDesigning solutionDiagrams such as data flow diagram or system flow chart are used to show context of new system.Data flow diagram is a graphical way of showing the flow of data within the system. O process, ? external entity, ? Data storage, ? data flow.System flow chart shows both flow of data and logic of system. Terminals, input/output, process, database, decision, flow line.Decision trees show all possible decisions and their results.External specificati on the appearance of new systemInternal specifications providing technical support to build the system, identify process required by new system, specifications for input data.Information technology application software may be available e.g. existing accounting softwares. If not then programme has to be written and meets the exact needs of new system.Technical specification new hardware support need or not.User documentation user manual(a) for new system. Must be user friendly.ImplementingThis is the stage of applying the new system. There are three ways of converting to the new system Direct conversion where the new system is completely replacing the old system. Does not allow time to check that the new one works correctly, old system is erased. Parallel conversion the new system and old system is run at the same time to allow room for error. Phrased conversion gradual implementation of new system. certain(prenominal) new ones are implemented while other old ones are still operation. Each operation is individually tested. Pilot conversion when a small part of the organization uses the new system. If new system fails, old is there to back it up.Training is needed to teach participants to use the new system. The participants include those who are learning and those who are teaching. Who needs to be trained is decided upon their existing knowledge.Testing, evaluating and maintainingSystem needs to be tested to ensure that it runs correctly. Results are compared to expectations and initial aims. Determines if change is required. Occurs after child adjustments.Evaluation is the ongoing process of assessing the system to identify areas of weakness that needs to be changed.Maintaining is the modifying of system after installation, upgrading by making minor improvements.IPT year11 exams study notes