How to use this search engine
You can use any of the three search methods that operate on defensesystems.com’s search engine – Boolean, set logic and natural language. Read below for a brief guide to each:
Boolean
This common search method lets you easily combine terms by using programming devices called "operators" such as "AND," "OR," "AND NOT.” The Defense Systems search engine uses this method as the default search system, and assumes the operator “AND” when more than one term is being searched.
AND requires all terms appear in a record.
OR retrieves records with either term.
AND NOT excludes terms.
Parentheses may be used to sequence operations and group words. Parenthesis MUST be used when searching using the operator “OR”.
Wild Card Character
For broad searches, you may use an asterisk (*) to represent multiple characters. For example: computer* would return items such as computer, computers, computerized, computeristic, etc. Please note: A "*" may be used only at the end of a search term.
Set logic
Set logic method is based on the mathematical concept of sets. The default behavior of the search is to locate an intersection (or 'AND') of every element within a query. This means that the query; "procurement regulation interface" is the equivalent to the boolean query: "procurement AND regulation AND interface."
Set logic operators
- '-' (without)
The '-'(minus) is the most commonly used logic symbol. It means the answer should EXCLUDE references to that item.
- '+' (mandatory)
The '+'(plus) symbol in front of a search item means that the answer MUST INCLUDE that item.
Sets (or lists) of things are specified by placing the elements within parenthesis, separated by commas. Example: (procurement,regulation,interface)
![1105 Media [justice]](http://www.defensesystems.com/images/ds1_pntmlogo.gif "1105 Media [justice]"){kind=small}
