In KAKEN system, a sequence of the same character type is recognised as a ‘word’. Some character types are searched on a word-by-word basis, and some are on a character-by-character basis.
The character types that are searched on a word-by-word basis are:
|English alphabet and numerical symbols||Cases and widths are ignored|
|Other symbols||Widths are ignored with some exceptions|
The character types that are searched on a character-by-character basis are:
|Hiragana, Katakana, Kanji, Hangeul|
A string of words separated with a space are treated as a ‘conjunctive search’. Records in different word orders are recognised as a match.
|Computer Science||computer science||○|
|science of computer||○|
|computer sciences||×||As it verifies a match at a word level (i.e. ‘science’ and ‘sciences’ do not match).|
In order to specify a conjunctive search, insert ‘AND’ in capital letters between words.
Inserting ‘+’ in front of a word won’t be recognised as a conjunctive search.
|#computer||×||The symbols do not match (i.e. ‘+’ and ‘#’).|
|computer||×||The symbol (i.e. ‘+’) is missing.|
By enclosing words in double quotation marks (“ ”), you can search for a phrase in the same word order.
|"Computer Science"||computer science||○|
|science computer||×||The word orders are different.|
|science of computer||×||It includes a word (i.e. ‘of’) between the words.|
|computer-science||×||It includes a symbol (i.e. ‘-‘) between the words.|
If you wish to use double quotation marks within a phrase, enter double quotation marks twice (i.e. ““).
By adding an asterisk (*) at the end of a word, you can search for strings with the matching prefix but with different endings.
|remake||×||The prefix is different from the query.|
By adding an asterisk (*) at the beginning of a word, you can search for strings with the matching suffix but with different beginnings.
|making||×||The suffix is different from the query.|
Middle match search is not available.
Exact Match for Researcher Names
If you wish to find a string matching ‘山田一’ but excluding ‘山田一郎’, enclose the researcher’s name between slashes (/ /) in the researcher search field.
You can operate a ‘disjunctive search’ by inserting ‘OR’ in capital letters between words.
|Computer OR Science||computer science||○|
When ‘AND’ and ‘OR’ are used in juxtaposition, ‘OR’ will be prioritised (i.e. it is different from the general logical operation).
|red AND blue OR green||red green||○||It recognises it as red AND (blue OR green).|
If you wish to search for records that do not include a certain word, insert ‘NOT’ in capital letters followed by a space in front of the word.
|gnu NOT unix||gnu||○|
|linux||×||It does not include ‘gnu’.|
Complex Operation Using Parentheses
By enclosing a string in parentheses (( )), you can set complex conditions such as changing the order of AND/OR.
|(red AND blue) OR green||green||○|
|(山 AND 川) OR (風 AND 谷)||川と山||○|