Classification
621 - Applied physics
486
620 - Engineering & allied operations
391
629 - Other branches of engineering
264
658 - General management
169
624 - Civil engineering
135
670 - Manufacturing
116
690 - Buildings
95
003 - Systems
43
650 - Management & auxiliary services
37
005 - Computer programming, programs & data
32
333 - Economics of land & energy
29
600 - Technology
26
004 - Data processing & computer science
24
300 - Social sciences
21
363 - Other social problems & services
19
530 - Physics
19
628 - Sanitary & municipal engineering
19
001 - Knowledge
18
006 - Special computer methods
17
531 - Classical mechanics; solid mechanics
17
338 - Production
15
660 - Chemical engineering
14
340 - Law
12
610 - Medicine & health
12
691 - Building materials
12
693 - Specific materials & purposes
12
307 - Communities
11
519 - Probabilities & applied mathematics
11
697 - Heating, ventilating & air-conditioning
11
352 - General considerations of public administration
10
720 - Architecture
9
304 - Factors affecting social behavior
8
616 - Diseases
6
306 - Culture & institutions
5
343 - Military, tax, trade & industrial law
5
500 - Natural sciences & mathematics
5
537 - Electricity & electronics
5
540 - Chemistry & allied sciences
4
570 - Life sciences; biology
4
150 - Psychology
3
321 - Systems of governments & states
3
330 - Economics
3
510 - Mathematics
3
551 - Geology, hydrology & meteorology
3
577 - Ecology
3
617 - Surgery & related medical specialties
3
900 - History & geography
3
000 - Computer science, information & general works
2
025 - Library operations
2
158 - Applied psychology
2
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