සිතුවෙමි… සමුදෙන්නට සිහිනයට
අසනි වැසි ඇද වැටෙද්දී
සිත දරාගත නොහැකි තරමට
වදන් එකිනෙක පෙළගැසෙද්දී..
විටෙක සිට කලු වළාවක මහ
හඬින් ගිගිරුම් දී වැටෙද්දී
පොළව සෝදා ගැලූ දහරින්
හැඟුනි සිත ගිය දුරක් නික්මී..
April 16, 2008
සිහිනය
April 10, 2008
March 7, 2008
XML
XML
XML was designed to describe data and to focus on what data is.
HTML was designed to display data and to focus on how data looks.
What is XML?
XML stands for EXtensible Markup Language
XML is a markup language much like HTML
XML was designed to describe data
XML tags are not predefined. You must define your own tags
XML uses a Document Type Definition (DTD) or an XML Schema to describe the data
XML with a DTD or XML Schema is designed to be self-descriptive
The main difference between XML and HTML
XML was designed to carry data.
XML is not a replacement for HTML.XML and HTML were designed with different goals:
XML was designed to describe data and to focus on what data is.HTML was designed to display data and to focus on how data looks.
HTML is about displaying information, while XML is about describing information.
XML does not DO anything
XML was not designed to DO anything.
Maybe it is a little hard to understand, but XML does not DO anything. XML was created to structure, store and to send information.
XML is free and extensible
XML tags are not predefined. You must “invent” your own tags.
The tags used to mark up HTML documents and the structure of HTML documents are predefined.
XML can Separate Data from HTML
With XML, your data is stored outside your HTML.
When HTML is used to display data, the data is stored inside your HTML. With XML, data can be stored in separate XML files. This way you can concentrate on using HTML for data layout and display, and be sure that changes in the underlying data will not require any changes to your HTML.XML data can also be stored inside HTML pages as “Data Islands”. You can still concentrate on using HTML only for formatting and displaying the data.
When HTML is used to display data, the data is stored inside your HTML. With XML, data can be stored in separate XML files. This way you can concentrate on using HTML for data layout and display, and be sure that changes in the underlying data will not require any changes to your HTML.XML data can also be stored inside HTML pages as “Data Islands”. You can still concentrate on using HTML only for formatting and displaying the data.
It is important to understand that XML was designed to store, carry, and exchange data. XML was not designed to display data.
XML is used to Exchange Data
With XML, data can be exchanged between incompatible systems.
In the real world, computer systems and databases contain data in incompatible formats. One of the most time-consuming challenges for developers has been to exchange data between such systems over the Internet.Converting the data to XML can greatly reduce this complexity and create data that can be read by many different types of applications.
In the real world, computer systems and databases contain data in incompatible formats. One of the most time-consuming challenges for developers has been to exchange data between such systems over the Internet.Converting the data to XML can greatly reduce this complexity and create data that can be read by many different types of applications.
XML and B2B
With XML, financial information can be exchanged over the Internet.
Expect to see a lot about XML and B2B (Business To Business) in the near future.
XML is going to be the main language for exchanging financial information between businesses over the Internet. A lot of interesting B2B applications are under development.
With XML, financial information can be exchanged over the Internet.
Expect to see a lot about XML and B2B (Business To Business) in the near future.
XML is going to be the main language for exchanging financial information between businesses over the Internet. A lot of interesting B2B applications are under development.
XML can be used to Share Data
With XML, plain text files can be used to share data.
Since XML data is stored in plain text format, XML provides a software- and hardware-independent way of sharing data.
This makes it much easier to create data that different applications can work with. It also makes it easier to expand or upgrade a system to new operating systems, servers, applications, and new browsers.
With XML, plain text files can be used to share data.
Since XML data is stored in plain text format, XML provides a software- and hardware-independent way of sharing data.
This makes it much easier to create data that different applications can work with. It also makes it easier to expand or upgrade a system to new operating systems, servers, applications, and new browsers.
XML can be used to Store Data
With XML, plain text files can be used to store data.
XML can also be used to store data in files or in databases. Applications can be written to store and retrieve information from the store, and generic applications can be used to display the data.
With XML, plain text files can be used to store data.
XML can also be used to store data in files or in databases. Applications can be written to store and retrieve information from the store, and generic applications can be used to display the data.
XML can make your Data more Useful
With XML, your data is available to more users.
Since XML is independent of hardware, software and application, you can make your data available to other than only standard HTML browsers.Other clients and applications can access your XML files as data sources, like they are accessing databases. Your data can be made available to all kinds of “reading machines” (agents), and it is easier to make your data available for blind people, or people with other disabilities.
With XML, your data is available to more users.
Since XML is independent of hardware, software and application, you can make your data available to other than only standard HTML browsers.Other clients and applications can access your XML files as data sources, like they are accessing databases. Your data can be made available to all kinds of “reading machines” (agents), and it is easier to make your data available for blind people, or people with other disabilities.
XML can be used to Create new Languages
XML is the mother of WAP and WML.The Wireless Markup Language (WML), used to markup Internet applications for handheld devices like mobile phones, is written in XML.
XML is the mother of WAP and WML.The Wireless Markup Language (WML), used to markup Internet applications for handheld devices like mobile phones, is written in XML.
SDLC
System Development Cycle
Before the start of the development of the project, the framework of system development processes has to be recognized. There are a number of different paradigms of software development, namely, the waterfall approach, the evolutionary development, formal specification and system assembly from reusable components [SO96]. Among these software development paradigms, the waterfall model is widely used for practical systems development.
System Development Cycle – Waterfall Model
Design Process
As quality of the application depends strictly on the system design, the design model for the project must be carefully selected. The design process involves developing several models of the system at different levels of abstraction [SO96]. Formality and detail are added as the design is developed with constant backtracking to correct earlier, less formal designs. Such feedback mechanism allows earlier designs to be improved.
The design process employed in this project will consist of 4 activities. They are:
(1) Architectural Design
(2) Procedural Design
(3) Database Design
(4) User Interface Design
There is no rigid boundary between the above stages but stage identification is useful to make the design visible and thus allow it to be manageable.
System Design Process
Design Methods
Two design strategies are widely adopted by software design. They are, namely, functional design and object-oriented design.
In this project, functional approach of system design will be followed. And the following structured design methods will be applied to the corresponding level of design as escribed in the previous section.
Data Flow Diagram :- will be applied to Architectural Design where system is modeled using data transformation.
Pseudo Code :- will be applied to Procedure Design to translate DFDs into procedural description.
Entity Relation Model :- will be applied to Database Design to describe the logical data structures employed in this system.
System Design Overview
The Motion Data Acquisition System is designed to help students understand the relationships between motions and kinematics graphs that describe the motions. This system can be integrated into the lesson in many different ways: Lecture demonstrations can be given by teachers to show how real data is collected and analyzed; Hands-on video experiment lets students explore themselves to the videos in their own paces; After-school practices are also possible for low ability students to revise the experiments. Undoubtedly, the Motion Data Acquisition System is a flexible and integrated system that collaborates the teaching and learning activities for kinematics. The following diagram shows the relationships between the Motion Data Acquisition System and its external entities.
