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Support : Dialog Search Aids : Numerical Indexing Fields in INSPEC Numerical Indexing Fields in INSPEC
Numerical data, such as temperature, pressure, frequency, etc., are indexed in the Numerical Indexing fields for records added to INSPEC since February 1987. Numerical indexing is controlled according to INSPEC's Numerical Data Thesaurus. Older records may include numeric data in the Identifier or Abstract fields, but such data are not standardized in these records and are not structured for the advanced searching capabilities provided by numerical indexing. Data are numerically indexed only if the relevant quantity is included in the Numerical Data Thesaurus, the data are included in the title or abstract or are encountered by the indexer when writing the abstract, and the data are considered important for retrieval. Categories The following two categories of numeric data are most likely to be indexed:
Unit conversions If the quantity being searched is given in different units of measure than those used in INSPEC's Numerical Data Thesaurus, it must be converted to the preferred thesaurus form for the search. Conversion formulas are given in the Thesaurus. The Unit of Measure used for a particular quantity may be verified by EXPANDing on the name of the quantity in the NI = field and then EXPANDing again to view related terms. For example, to obtain conversion formulas for temperature from Celsius or Fahrenheit to Kelvin (the preferred unit):
A direct display can also be obtained by enclosing the term in parentheses:
Values are displayed in the indexes using exponential notation:
The values are searchable in different formats. For example, a power output of 0.03 watts is expressed in exponential notation as 3.0 X 10-2W and is indexed as WA = 3.0E-02. It may be searched in either exponential or decimal notation, and leading or trailing zeroes may be included or omitted, i.e., all of the following searches are equivalent: SELECT WA=3.0E-02 SELECT WA=3E-2 SELECT WA=0.03 SELECT WA=.03 When searching for values with positive exponents, the plus (+) sign in the exponential notation must be masked with quotation marks, for example, SELECT GD = " 5E + 3 " to search for a galactic distance of 5,000 parsecs. Alternatively, the plus (+) sign can be omitted, e.g., SELECT GD=5E3. Truncation is not allowed for searching numeric data. The smallest and largest numbers that may be searched are 5.4E-79 and 7.2E+75. Searching by Ranges or by Relational Operators There are two ways of selecting a numeric range: Range Searching (using the colon) and Relational Searching (using relational operators).Use the colon (:) in a SELECT statement to link the upper and lower limits of the range. For example, to retrieve records containing information about a mass between 10,000 and 20,000 kg, enter one of the following statements: S MA=10000:20000 S MA=10,000:20,000 S MA=10K:20K S MA=10E3:20E3 S MA=1E4:20E3 Relational operators provide an alternative search technique. The following operators can be used for a relational searching:
< Less than >= Greater than or equal to (same as =>) <= Less than or equal to (same as =<) The following searches are equivalent: SELECT PO=4E-5:2E-4 SELECT 4E-5<=PO<=2E-4 NI is the display code for all of the numeric indexing fields. top |
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E4 0 NI=TESLA (See NI=MAGNETIC FLUX DENSITY; use MD=)
E5 0 NI=THICKNESS (See NI=SIZE; use SI=)
E6 65339 5 NI=TIME (In seconds (s); use TM=)
E7 0 NI=TON (See NI=MASS; in kilograms (kg); use MA=)
E8 0 NI=TONNE (See NI=MASS; in kilograms (kg); use MA=)
E9 0 NI=TORR (See NI=PRESSURE; in pascals (Pa); use PR=)
E10 0 NI=TRANSMISSION SPEED (See NI=BIT RATE; use BI=)
E11 34571 NI=V (See NI=VOLTAGE; use VO=)
E12 2139 NI=VA (See NI=APPARENT POWER; use AP=)
Enter P or PAGE for more
?EXPAND E3
Ref Items Type RT Index-term
R1 229589 2 *NI=TEMPERATURE (In kelvin (K); use TE=)
R2 0 S K = degC + 273.15
R3 0 S K = degF + 459.67 * 0.5555556