TERM2 THEORY REVISION
Data Collection
- Refers to the process of gathering and measuring information in a
digital format from various sources for processing, storage, analysis,
and utilization.
RFID
- Radio Frequency Identification
- Data capture technology that was designed to store more data and
work more interactively than conventional barcode systems.
- Uses radio frequencies to identify objects by means of tags attached
to the object
- Examples Pets, eTolls
- Makes data capture efficient
- Tag placed on item, reader reads the tag for info
Parts of RFID
The Tag
- Contains antenna, circuitry and a microchip, sometimes a battery
- Sizes vary
- Size of antenna makes the communication possible at different
distances
The Reader
- Uses antenna, creates electromagnetic field that is used for passive
tags to create electricity for themselves
- Reader reads the radio signals broadcasted by tags and sends info
to software for processing
- Reader can also be any size
Advantages
- Read more than one tag at a time
- Read tags even if they are in boxes
- Interact with data and software stored on tag
- Read tags when they travelling at speed
, - Use tag to collect and broadcast info about the
environment(temperature)
Data Warehousing
- Huge collection of data, often accumulated from a range of sources
such as separate databases within a company
- Aim is to provide suitable storage and tools to be able to extract and
analyse info from huge volumes of data
Data Mining
- The discovery of new patterns in data
- Carried out by software
- Human involvement may include: Selecting and preparing data
sets
Developing data mining software and
algorithms
Interpreting and verifying results
delivered by the data mining software
- Data mining is possible by: Increased power of modern CPUs
Lower cost of hardware
Faster and more efficient
software
Greater availability of data
Database Design
Rules of relational databases:
Data is stored in tables
A table represents a single concept or entity
Each item in one instance of entity is called a record
Each record is made up of attributes of the entity
Database contains one or more tables
Each record must contain a field making the record unique(PK)
PK can be composite (consist of more than one field)
Each record contain a field linking to other tables (FK)
No data field may appear more than once in a table
No field may appear in more than 1 table unless its FK
Normalisation
- Series of steps that need to be followed to ensure databases are
designed correctly
Steps of designing a database:
, - Select the data
- Structure the data
Anomalies
- Insert Design of DB prevents a user from capturing data when
they want to
- Delete Deleting one piece of data results in the simultaneous
removal of other data
- Update When an item of data changes, it has to be altered in
multiple records in the table
Data Collection
- Refers to the process of gathering and measuring information in a
digital format from various sources for processing, storage, analysis,
and utilization.
RFID
- Radio Frequency Identification
- Data capture technology that was designed to store more data and
work more interactively than conventional barcode systems.
- Uses radio frequencies to identify objects by means of tags attached
to the object
- Examples Pets, eTolls
- Makes data capture efficient
- Tag placed on item, reader reads the tag for info
Parts of RFID
The Tag
- Contains antenna, circuitry and a microchip, sometimes a battery
- Sizes vary
- Size of antenna makes the communication possible at different
distances
The Reader
- Uses antenna, creates electromagnetic field that is used for passive
tags to create electricity for themselves
- Reader reads the radio signals broadcasted by tags and sends info
to software for processing
- Reader can also be any size
Advantages
- Read more than one tag at a time
- Read tags even if they are in boxes
- Interact with data and software stored on tag
- Read tags when they travelling at speed
, - Use tag to collect and broadcast info about the
environment(temperature)
Data Warehousing
- Huge collection of data, often accumulated from a range of sources
such as separate databases within a company
- Aim is to provide suitable storage and tools to be able to extract and
analyse info from huge volumes of data
Data Mining
- The discovery of new patterns in data
- Carried out by software
- Human involvement may include: Selecting and preparing data
sets
Developing data mining software and
algorithms
Interpreting and verifying results
delivered by the data mining software
- Data mining is possible by: Increased power of modern CPUs
Lower cost of hardware
Faster and more efficient
software
Greater availability of data
Database Design
Rules of relational databases:
Data is stored in tables
A table represents a single concept or entity
Each item in one instance of entity is called a record
Each record is made up of attributes of the entity
Database contains one or more tables
Each record must contain a field making the record unique(PK)
PK can be composite (consist of more than one field)
Each record contain a field linking to other tables (FK)
No data field may appear more than once in a table
No field may appear in more than 1 table unless its FK
Normalisation
- Series of steps that need to be followed to ensure databases are
designed correctly
Steps of designing a database:
, - Select the data
- Structure the data
Anomalies
- Insert Design of DB prevents a user from capturing data when
they want to
- Delete Deleting one piece of data results in the simultaneous
removal of other data
- Update When an item of data changes, it has to be altered in
multiple records in the table
