SIN # Information Systems
Information management
Data is defined as raw facts, information indicates that organized help answer questions and solve problems of data
Information Systems: Software to help us organize and analyze data.
The three most popular general application of information systems is a spreadsheet, database management systems and e-commerce.
Spreadsheet software
Spreadsheet: allowing the user to program the cell with a tissue and analyzing data.
Cells: the spreadsheet for storing the element data or formulas.
Spreadsheet formulas
Spreadsheet functions: spreadsheet software may be used to provide a calculation function formula.
Range: The endpoint is assigned a contiguous set of cells.
| function | Compute |
|---|---|
| SUM | A specified set of values and |
| COUNT | The number of non-empty cells |
| MAX | A set of maximum values specified in the |
Circular references
When the calculation result to the error dependent of each other a group of formula.
Spreadsheet analysis
Analysis Simulation assumptions: modify the spreadsheet represents a value assumed to observe changes in the assumptions have any effect on the data.
Database Management Systems
Database: structured data binding
Database management system consists of
Physical database - a collection of stored data files
Database Engine - Support for access and modify the contents of the database software
Statute data stored in the logical structure of the database - the database schema
Database Engine interaction with a dedicated database language, this language allows the user to specify the structure of the data, add, modify and delete data, queries the database to obtain the specified storage data.
Relational Model '
In a relational DBMS, the table would like to organize data and relationships between them. Table is a collection of records. Record is a collection of related fields.
Table one or more domains have been identified as key fields. In all other domain key records in a table that uniquely identifies this record.
relationship
A table can be used both denote the set of relationships between objects.
Structured Query Language
SQL is a comprehensive database management language for relational databases, which include the development of database schema and statements to add, modify and delete statements contents of the database.
Inquire:
select clause determines the return of those properties
from clause determines which table to query
where clause limiting the returned data
Modify the contents of the database:
insert / update / delete statement
Database Design
One common method of designing a relational database called entity relationship modeling. ER modeling is the main tool of ER diagram.
FIG ER captured using graphical form an important record types, attributes, and relationships.
Held records indicate the type of oval indicates a recording domain, diamonds represent relationships.
Cardinality constraints: In the ER diagram, a number of relationships may exist between entities.
E-commerce
artificial intelligence
Thinking Machine
Artificial Intelligence is the study of the subject computer system for modeling human thought and human blanket application of only
Turing Test
Turing Test: a behavioral method for a computer system to determine whether it is intelligent.
Asked respondents were to judge which is the computer. This process will be repeated more than one person to perform. This hypothesis was tested if the computer is hidden from enough people, then we can see him as intelligent.
Weak equivalence: Equivalence of two systems based on the results
Strong equivalence: two systems are equivalent and based on the results of the current processing method which results.
Various aspects of AI problem
Knowledge Representation
It can be expressed in natural language, semantic web and can also be used to retrieve tree
Semantic Web
Semantic Web: knowledge representation notation relationship between objects.
Inheritance is an object description is (is-a) more specific version of another object.
Examples of the (instance-of) the relationship between a real object and the description of such objects.
The difficulty is to establish the right relationship model and fill the entire network with complete and accurate data.
Search tree
Search tree: antagonistic selection structure represents all situations.
Each section can not have a complete analysis
Depth Priority: priority retrieval path down the tree
Breadth-first: the priority of each lateral search tree
expert system
Knowledge-based systems: the use of specific software information collection
Expert systems: software systems based on the knowledge of human experts
Rule-based systems: software systems based on a set of if-then rules
Inference engine: handling rules to draw conclusions software
Neural Networks
Artificial Neural Networks: Try to mimic human neural network computer knowledge representation.
Artificial neural networks
Element accepts a certain number of input values, to generate the effective weight value of 0 or 1. The output element is the product of all input values and its weight.
Each element has a numeric threshold, effective weight elements will be compared to this threshold. Greater than the threshold, equal to 1
The right to adjust the course of the neural network and the threshold is called training.
Natural Language Processing
* Voice recognition - recognizing human blanket words spoken
* Natural Language Understanding - interpreting the information conveyed by the human
· Speech synthesis - the reproduction of the human voice
Speech Recognition
Factors: a collection of basic voice in any language developed in the unit.
Dynamically generating a voice output speech generation method, computer analysis of the letters to form words, generating a sequence of letters in an attempt to sound corresponding utterance.
Another speech synthesis method is a human voice digital recording.
Speech Recognition
The most successful system uses incoherent speech, in which each word is clearly divided out.
Voiceprint: that the human voice frequency changes over time in FIG.
Natural language understanding
Lexical ambiguity
Syntactic ambiguity
Refer to the ambiguity
Robotics
Perception - Planning - Execution rebate
The sensor data is interpreted by the world model, and then generate an action plan. Robot control system to perform the steps planned. Once the robot moves, she will get the new sensor data, this cycle will be repeated, the new data into the semantic network.
Conceiving architecture
The new paradigm is no longer a robot to simulate the entire world, but rich set of simple robot behavior, each behavior associated with it essential part of the robot world together.
Avoid obstacles behavior has priority.
Three Laws of Robotics, Isaac Asimov defined entirely Conceiving used in this architecture.
Physical seen
The most commonly used system is the wheel, track and mechanical legs
Simulation, graphics, games and other applications
What is simulation
The so-called simulation model is to design complex systems as well as for the observation and its experimental operation.
Model can be either a physical spring, physical objects may be software controlled, and may be purely logical.
Complex systems
The most suitable simulation system is dynamic, interactive and complex systems.
The behavior of dynamic systems will change over time. This behavior can be understood in varying ways and captured by mathematical formulas.
The system should be composed of many objects, otherwise it is a waste of time simulation
model
Model: Abstract real system, it is a rule of the objects in the system and manage these objects interact.
Structural model
The key is to determine the structural model is sufficient to describe a small set of features or characteristics of the surveyed behavior.
Model is an abstraction of the real system, not the system itself.
Continuous analog: a set of differential equations reflecting the relationship between the feature set represents a change in time.
Characterized in having a continuous analog of theoretical nature.
Discrete event simulation:
Discrete event simulation consists of entities, attributes and time.
Objects through the system is usually expressed as an entity.
Special model
Queuing System
Queuing system consists of servers and object queues waiting to be served.
It is a FIFO queue structure,
please wait
The purpose of the queue system is fully utilized as a server, waiting time in reasonable limits. '
Other types of two FIFO queues queue priority queue
Weather models
Weather forecast
Weather forecasting computer models used to assist rather than replace the forecaster.
A small error input variable error will result in the integration process, to continue to increase.
Hurricane tracking
Since the model is used in hurricane tracking a moving target, so they are called floating model.
Special model
Weather model may be changed to a specific model.
Computational Biology
It contains
Bioinformatics
Computational Biology Modeling
Calculation genome
Molecular modeling
Protein Structure Prediction
The necessary computing power
Digital weather forecast and other applications must catch up with the time difference is, if the weather forecast yesterday, today, have not received, then there is no use of.
Computer Graphics
Computer graphics in many areas of computer science plays a role. The most common application is a modern operating system, graphical user interface. Files and folders on the screen by an icon representation, icon also explain the type of file, and computer interaction design point, click and drag.
Application of soft-page computer graphics software, word processing and desktop publishing. 'The company is also using computer graphics to design and manufacture products.
Works of light
The human visual system can play a role because the object reflects light, the light that enters our eyes.
Object shape
Light simulation
Modeling complex objects
Let the object move
Each frame image object moves a distance slightly reduced compared.
game
The computer game is a real player in the world to introduce a computer simulation of a virtual world participants.
Game Category:
Design game action adventure game of life simulation games strategy games role-playing game
Create a virtual world
All the game engine must include a renderer.
Game Design and Development
Game Programming
Then there is the most important C ++ Java and C
problem
Do not understand the principles of computer graphics
Law of depth-first search tree, breadth-first method