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Semantic Web
Semantic Web
Address me as “Scott”
Being able to do something is more important than memorizing. I will not ask you to memorize. My tests ask you to think and explain. I ask you to take a position.
Your grade on a test (mid-term, final) is not the final grade.
You must successfully complete all projects to pass the course.
You pick your grade – I'll explain.
Semantic Web
Turing MachineP-V Semaphore – Unix – Flat Files1972, Dr. E. F. Codd invented Relational Database, Linear Algebra → Data Storage.RDBMS – Transactions – Bob Epstein1988 --- 1995 --- Databases fault tolerant and load balanced. They were tightly coupled.Startup and you want to do load balancing...Larger than anyone ever has..... What do you do.?
Semantic Web
Where is LAMP best. Linux, Apache, MySQL, Php
1) Your views closely model your database design.
2) Security requirements are not excessive.
Where is War best.
1) You views do not closely model your database
Design. In fact there probably is not RDBMS.
Elastic.
Semantic Web
Semantic Web
I. What is Semantic Web?II. Why Semantic Web?III. 5 Rules of Software Development
Semantic Web
Syntactic/syntax: relating to structureSemantic: relating to meaning
The Semantic Web allows information to be processed automatically by tools as well as manually and can infer potential relationships among pieces of data. It extends principles of the World Wide Web from documents to data through the development of a common framework that allows data to be shared and reused across application, enterprise, and community boundaries.
Semantic Web
The Semantic Web solves problems today that were previously unsolvable:
• Facilitates interchange between entities with ever-changing requirements without breaking systems.
• Provides the ability to share or annotate search results/data.
• Provides capability to analyze items that are potentially related.
Semantic Web
5 Rules of Software Development
+ Complex Problems
Semantic Web
Semantic Web
5 Rules of Software Development
1. W3C specifications ahead of JSR specifications. 2. JSR ahead of defacto standards. 3. Defacto standards ahead of custom development. 4. Compositional patterns to create software systems. 5. Use design patterns when creating custom code.
Semantic Web
Rule #1– W3C specifications ahead of JSR specifications
Today's application requirements regularly include free form objects and references to these objects.
These free form objects and their structures signify the need for variable ontologies.
To this end, W3C specifications include Resource Description Framework (RDF).
Semantic Web
A remote calling mechanism for accessing RDF web services may be developed through the Simple Object Access Protocol (SOAP) or JSR 181 or alternately representational state transfer (REST) or JSR 311. Alternately, we could use the defacto standard of Apache Axis.
In exploring the problem in more detail, we first consider each technology. This examination leads to the conclusion that, since they are virtually free, applications shall implement web services with JSRs 181 and 311. Since Axis does not have long term support and standards exist for the same functionality, do not consider Axis for use.
Rule #2– JSR ahead of defacto standards
Semantic Web
Rule #3– Defacto standards ahead of custom development
Examples include:
•Mashups•Wikis•Jena API for the creation of RDF systems
Semantic Web
A practical example of this type of composition is the use of JSR 181 annotations in conjunction with Jena for an RDF implementation and doing this within the same java class.
Rule #4– Compositional patterns to create software systems
Semantic Web
Rule #5– Use design patterns when creating custom code
• A design pattern is a description or template for how to solve a problem that can be used in many different solutions.
• Use of these patterns improves the quality of software by using previously vetted interactions.
Semantic Web
• Provides for interchangeable format systems to exchange data removing the possibilities for rewrites when information changes.
• Flexible storage so schema doesn’t have to change as problems become more complex.
•Next generation of visualization through browsers.
•Ability to add analytical data through reasoning.
Variable Ontologies
Semantic Web Layers
RDF Schema Individuals
XML and XMLS Datatypes
URIs and Namespaces
Applications
Ontology Languages (OWL Full, OWL DL, and OWL Lite)
RDF and RDF/ XML
Semantic Web
• Provides for interchangeable format systems to exchange data removing the possibilities for rewrites when information changes.
• Flexible storage so schema doesn’t have to change as problems become more complex.
•Next generation of visualization through browsers.
•Ability to add analytical data through reasoning.
Variable Ontologies
Semantic Web
Example: The hierarchy of the Ford Taurus
Variable Ontologies – Ford Taurus Hierarchy
Semantic Web
Expanding the Ford Motor Company ontology will lead to a more formalized data structure and with implied relationships between different pieces of data. For instance Ford produces more than one type of vehicle, and they also make parts for the vehicles they manufacture. Look at what happens when the F-150 Truck and Expedition Sport Utility Vehicle and some vehicle parts like a chassis and engine for each are added.
Variable Ontologies – XML Diagram
Semantic Web
What happens when Ford Motor Company uses an outside parts manufacturer to supply a part for one of the vehicles it manufactures? What happens when Ford produces another vehicle under a different make and model like the Mercury Sable that is virtually identical to the Taurus? What happens when Ford Motor Company purchases Hughes Aerospace and begins producing aircraft and aircraft parts?
Variable Ontologies – XML Diagram
Semantic Web
The diagram below shows how the OWL has simplified the data representation cleaning up the duplication and establishing the relationships between the different data objects.
Variable Ontologies – RDF Diagram
