Top IPC subclasses
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1
|
H01L
|
28
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Semiconductor devices; electric solid state devices not otherwise provided for
|
|
2
|
H04B
|
13
|
transmission
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|
3
|
H02M
|
11
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apparatus for conversion between ac and ac, between ac and dc, or between dc and dc, and for use wit
|
|
4
|
B60L
|
11
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electric equipment or propulsion of electrically-propelled vehiclesmagnetic suspension or levitation
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|
5
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G05F
|
7
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systems for regulating electric or magnetic variables
|
|
6
|
G01R
|
7
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Measuring electric variables; measuring magnetic variables
|
|
7
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H02J
|
7
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circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
|
|
8
|
C01B
|
6
|
non-metallic elementscompounds thereof
|
|
9
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F02G
|
6
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hot-gas or combustion-product positive-displacement engine plantsuse of waste heat of combustion eng
|
|
10
|
C30B
|
5
|
single-crystal growthunidirectional solidification of eutectic material or unidirectional demixing o
|
|
11
|
A01G
|
5
|
Horticulture; cultivation of vegetables, flowers, rice, fruit, vines, hops, or seaweed; forestry; watering
|
|
12
|
G01N
|
4
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Investigating or analysing materials by determining their chemical or physical properties
|
|
13
|
G01J
|
4
|
measurement of intensity, velocity, spectral content, polarisation, phase or pulse characteristics o
|
|
14
|
G01K
|
4
|
measuring temperaturemeasuring quantity of heatthermally-sensitive elements not otherwise provided f
|
|
15
|
C01G
|
3
|
Compounds containing metals not covered by subclasses C01D or C01F
|
|
16
|
C03C
|
3
|
chemical composition of glasses, glazes, or vitreous enamelssurface treatment of glasssurface treatm
|
|
17
|
D21H
|
3
|
pulp compositionspreparation thereof not covered by subclasses , impregnating or coating of papertre
|
|
18
|
A01C
|
2
|
Planting; sowing; fertilising
|
|
19
|
B82B
|
2
|
nano-structuresmanufacture or treatment thereof
|
|
20
|
G05D
|
2
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systems for controlling or regulating non-electric variables
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