The Columbian Exchange has been one of the most significant events in the history of world ecology, agriculture, and culture. The term is used to describe the enormous widespread exchange of plants, animals, foods, human populations (including slaves), communicable diseases, and ideas between the Eastern and Western hemispheres that occurred after 1492. Many new and different goods were exchanged between the two hemispheres of the Earth, and it began a new revolution in the Americas and in Europe. In 1492, Christopher Columbus' first voyage launched an era of large-scale contact between the Old and the New World that resulted in this ecological revolution: hence the name "Columbian" Exchange.
Tuesday, April 29, 2008
Tuesday, April 22, 2008
Piri Reis map
The Piri Reis map ("Piri" pronounced /piɹi/) is a famous pre-modern world map created by 16th century Ottoman-Turkish admiral and cartographer Piri Reis. The map shows part of the western coasts of Europe and North Africa with reasonable accuracy, and the coast of Brazil is also easily recognizable. Various Atlantic islands including the Azores and Canary Islands are depicted, as is the mythical island of Antillia. The map is noteworthy for its depiction of a southern landmass that some controversially claim is evidence for early awareness of the existence of Antarctica.
Tuesday, April 15, 2008
Systems Development Life Cycle
Systems Development Life Cycle (SDLC) or sometimes just (SLC) is defined by the U.S. Department of Justice (DoJ) as a software development process, although it is also a distinct process independent of software or other information technology considerations. It is used by a systems analyst to develop an information system, including requirements, validation, training, and user ownership through investigation, analysis, design, implementation, and maintenance. SDLC is also known as information systems development or application development. An SDLC should result in a high quality system that meets or exceeds customer expectations, within time and cost estimates, works effectively and efficiently in the current and planned information technology infrastructure, and is cheap to maintain and cost-effective to enhance.
Tuesday, April 08, 2008
The principles of Application Lifecycle Management (ALM)
The principles of Application Lifecycle Management (ALM) are integral to mature development disciplines. Experienced development organizations employ these principles to ensure quality in the products they develop.
Application Lifecycle Management involves a variety of typical software project phases:
- Project management
- Project tracking
- Requirements planning
- Design and development
- Quality Assurance
- Release management
Friday, April 04, 2008
Database security
Traditionally databases have been protected from external connections by firewalls or routers on the network perimeter with the database environment existing on the internal network opposed to being located within a demilitarized zone. Additional network security devices that detect and alert on malicious database protocol traffic include network intrusion detection systems along with host-based intrusion detection systems.