COMPONENTS OF GEOGRAPHIC INFORMATION SYSTEM (GIS)

A working GIS integrates these five key components: hardware, software, data, people and methods.

1. Hardware: Hardware is the computer on which a GIS operates. Today, GIS runs on a wide range of hardware types, from centralized computer servers to desktop computers used in stand-alone or networked configurations.
2. Software: GIS software provides the functions and tools needed to store, analyze and display geographic information. Key software components are:

• A database management system (DBMS).
• Tools for the input and manipulation of geographic information.
• Tools that support geographic query, analysis and visualization.
• A Graphical User Interface (GUI) for easy access to tools.

3. Data: Maybe the most important component of a GIS is the data. Geographic data and related tabular data can be collected in-house or bought from a commercial data provider. Most GIS employ a DBMS to create and maintain a database to help organize and manage data.
4. People: GIS technology is of limited value without the people who manage the system and to develop plans for applying it. GIS users range from technical specialists who design and maintain the system to those who use it to help them do their everyday work.
5. Methods: A successful GIS operates according to a well-designed plan and business rules, which are the models and operating practices unique to each organization.

 

FUNCTIONS OF THE MAJOR HARDWARE COMPONENTS IN A COMPUTER SYSTEM

The main function of a computer system is to process information. An example, operation done using a computer is to create a document. The processing of this information goes through a set of phases, each of these phases require its own set of devices.

• The first phase is the input phase, where data is entered into the computer system through input devices.
• After data is inputted into the computer system, it is then processed and some changes or computations are done by the Central Processing Unit (CPU).
• During the time which the document is being modified, the document needs to be stored temporarily in the computer’s main memory for the CPU to access it.
• To save the document for future use, it is stored in secondary storage.
• The document is then outputted to the screen or printed.

 

MAJOR HARDWARE COMPONENTS

The major hardware components of a computer can be broadly categorized as:

• CPU (CU, ALU).
• Main Memory/Immediate Access storage (primary storage).
• Secondary storage.
• Input/output devices.

 

1. CPU: The Central Processing Unit (CPU) is the brain of a computer system. It carries out the instructions of a computer program, to perform the basic arithmetical, logical and input/output operations of the system. The CPU is made up of the Control Unit (CU) and the Arithmetic and Logic Unit (ALU).

• CU: The control unit is part of the CPU that instructs other parts of the computer system to carry out program instructions.
• ALU: The ALU is a digital circuit that performs arithmetic and logical operations.

2. Main Memory: Main memory is a form of Immediate Access Storage also known as primary storage, it is volatile memory directly accessible to the CPU and is used to store data actively operated on. The CPU continuously reads instructions stored there and executes them as required. Information stored in main memory is lost when the computer is powered off.
3. Secondary Storage: Secondary storage differs from primary storage in that it is not directly accessible by the CPU. The computer usually uses its input/output channels to access secondary storage and transfers the desired data using an intermediate area in primary storage. Secondary storage does not lose the data when the device is powered off and it is non-volatile. Secondary storage devices include the Hard Drive, Flash Drive, and Memory Card.
4. Input Devices: An input device is any peripheral (piece of computer hardware equipment) used to provide data to the computer. Input devices include the Mouse, Keyboard, Touch Screen Monitor, Scanner, Track Pad, Microphone, Joystick, and Web Camera.

• Output devices: An output device is any piece of computer hardware equipment used to communicate the results of data processing carried out by the computer to the outside world. Output device include the Speaker, Printer, Monitor, Plotter.

 

THE SOFTWARE COMPONENTS AND THEIR USES

• System Software: System software sits directly on top of your computer’s hardware components (also referred to as its bare metal). It includes the range of software you would install to your system that enables it to function. This includes the operating system, drivers for your hardware devices, linkers and debuggers. System software can also be used for managing computer resources. System software is designed to be used by the computer system itself, not human users.
• Application Software: Unlike systems software, applications designed to use by end-users. Application software, in essence, sits on top of system software, as it is unable to run without the operating system and other utilities. Application software include things like database programs, word processors and spreadsheets, e-mail applications, computer games, graphics programs and such. Generally, people will refer to application software as software.

 

TYPES OF APPLICATION SOFTWARE

The Growing List of “Ware” Terminology

Today we find new terms created frequently to classify types of applications software. You have classifications based on usage. For example, games or financial software, office applications and other categories where the category is derived based on the main use of the software. Unfortunately, we also have a newer group of software related terms that have a negative association. While the application software itself may be useful, it may also carry hidden programs or utilities that may cause undesirable effects.

 

DISTINGUISH BETWEEN POSITIONAL AND RELATIONAL DATA

• Position Data: Refers to data that identifies the precise location of the device that collect geospatial data.
• Relational Data: Relational data consist of data that a result from a connection. Relational data is a jointly owned property among the actors as a result of their association. Some examples of relational data are: Kinship, friendship, boss/subordinate, project team membership and group association.

 

STATE THE PROCEDURES OR RULES FOR GIS

The GIS procedure creates and maintains the spatial databases that are used by SAS/GIS software. A SAS/GIS spatial database consists of the following elements:

1. SAS data sets that contain the coordinates and identifying information for the spatial features.
2. A spatial entry (a SAS catalog entry of type GISSPA) that identifies which SAS data sets contain spatial information. The spatial entry also stores the following elements:

• Composites that define how the variables in the spatial data are used.
• Names of the polygonal indexes that define the boundaries of area layers for the map.
• A lattice hierarchy that defines which features in the spatial data enclose or are enclosed by other features (the relationships among the polygonal variables).
• Information about the projection method that is used for the stored spatial data.

 

A spatial entry alternatively can contain references to two or more other spatial entries that have been merged into a single spatial database.

• A coverage entry (a SAS catalog entry of type GISCOVER) that selects a subset of the spatial data that is available for display in a map.
• One or more layer entries (SAS catalog entries of type GISLAYER) that identify features that have common characteristics and specify how they are displayed as layers in the map.

© a map entry (a SAS catalog entry of type GISMAP) that specifies which layers from a particular coverage are included in a map. The map entry also stores the following information:

• The names of attribute data sets that are associated with the map, along with definitions of how the attribute data is linked to the spatial data.
• The name of a SAS data set that contains labels for map features.
• Definitions of GIS actions that can be performed when map features are selected.
• Definitions for map legends.
• Values for display and projection options.

 

1. Graduate Registration: To register as a graduate for this scheme, you must:

• Be a citizen of Nigeria (must provide a valid ID).
• Be between ages 18 – 40 years (must provide birth certificate).
• Have completed the mandatory NYSC or exempted.
• Be holder of a degree equivalent (e.g. BSc, BEng, BA and HND) certificate or higher qualification.
• Have a recent passport type photo ready to be uploaded during online registration. Please note; size of image must not exceed 99kb.
• Complete the online registration form.
• Make available all original documents for sighting at point of selection.

 

2. Employer Registration: To register as an employer for this scheme, you must:

• Be registered with Corporate Affairs Commission (CAC) and other relevant professional bodies.
• Provide evidence of VAT registration and the latest Tax Clearance Certificate.
• Prove that they are economically viable and engaged in legitimate business by providing other relevant documents e.g. Company profile and audited accounts. This information will be used to examine the firm’s progression since its inception.
• Be prepared to provide a mentoring plan for each intern.
• Be prepared with specific assignments for interns.
• Be able to employ interns for a period of one (1) year.

Companies with outstanding tax issues or where the owners or directors have convictions for fraud will not be eligible to register for the programme.

 

3. Internship Position Posting: Intern positions posted must.

• Be legitimate positions available on the stated timescale.
• Be suitable work for a Graduate.
• Not require the Graduate to undertake work that is illegal or unsafe.
• Meet standard safety regulations/facilities.
• Be able to provide at least 12 months of skills development.
• Be able to provide a mentoring plan to guide skills development.

 

4. Applying for Work: When applying for positions as a Graduate you must.

• Be available to work at the chosen business and location.
• Be willing to undertake a full 12 month placement.
• Be prepared to comply with the employer’s safety and employment practices.

 

5. Payment of Interns

• Payment of Intern will be undertaken directly by the PW/WYE PIU to the Graduate intern.
• Neither the Graduate nor the employer are required to pay any fee for using the Graduate intern scheme service, and no fees, charges or commissions are to be paid to any party in relation to this scheme by the Graduate or the Employer.

 

IDENTIFY GIS HUMANWARE

Humanware is hardware and software that emphasizes user capability and empowerment and the design of the user interface. The process of building humanware generally consists of these steps:

1. Define users (age, mindset, environment context, previous product experience expectations, and so forth) and what they really want to do.
2. Identify tasks they will need to do or capabilities they will want.
3. Specify usability objectives (if possible, these should be measurable, such as how long to do something or how many mouse clicks to get to a specified task point) for each task or capability.
4. Build a prototype of the user interface (it can be a paper or stimulated prototype if the time is short).
5. Test and verify or correct the prototype.
6. Provide the prototype and usability objectives to the program designers and coders.
7. Test the code against the prototype and objectives and, if necessary, redesign or recode the software.
8. Test the product with users or valid test subjects and revise as necessary.
9. Get feedback from users and continually improve the product.

Philips Research uses the term for both software and hardware that is specially designed to interact with users, including its speech synthesis and speech recognition microchips.