-
553.
Length measurement
Subjects
Mensuration
-
554.
Levers
Subjects
-
555.
Library Web sites
Subjects
Web sites
-
556.
Lifesaving
Subjects
DisastersFirst aid in illness and injuryCivil defense
-
557.
Light emitting diodes
Subjects
Semiconductor diodes
-
558.
Lighthouses
Subjects
Hydraulic structuresAids to navigation
-
559.
Lighting
Subjects
Light
-
560.
Lighting
Subjects
Environmental engineering (Buildings)
-
561.
Lighting (Cinematography)
Subjects
Cinematography
-
562.
Lightning conductors
Subjects
Fire prevention
-
563.
Lime industry
Subjects
-
564.
Limekilns
Subjects
Furnaces
-
565.
Linear accelerators
Subjects
Particle accelerators
-
566.
Linear electric circuits
Subjects
Electric circuits
-
567.
Linear integrated circuits
Subjects
Integrated circuits
-
568.
Liquid crystal displays
Subjects
Information display systems
-
569.
Lithium cells
Subjects
Electric batteries
-
570.
Local radio
Subjects
Local mass mediaRadio broadcasting
-
571.
Location-based services
Subjects
Information storage and retrieval systems
-
572.
Locomotives
Subjects
RailroadsMachinery
-
573.
Loudspeakers
Subjects
Audio equipmentTransducers
-
574.
Low temperature engineering
Subjects
EngineeringLow temperatures
-
575.
Lubrication and lubricants
Subjects
FrictionTribology
-
576.
Lysimeter
Subjects
Last updated dated: 05/07/2025