Subject
National security
31
Watershed management
28
Revegetation
18
Water use
17
Reclamation of land
16
Water resources development
16
Mountain plants
15
Water quality management
15
Security, International
14
Tundra plants
12
Water Law and legislation
12
Geology
11
Photovoltaic power generation
11
Robotics
11
Wind power Research
11
Artificial intelligence
10
Computer networks
9
Computer science
9
Information technology
9
Renewable energy sources
9
Water-supply
9
Climatic changes
8
Computer security
8
History
8
Marine resources conservation
8
Software engineering
8
Architecture and energy conservation
7
Data mining
7
Ecosystem management
7
Endangered species
7
Fishery management
7
United States Foreign relations
7
United States Military policy
7
Electronic commerce
6
Marine parks and reserves
6
Solar cells Research
6
Agriculture
5
Agriculture Economic aspects
5
Appropriations and expenditures
5
Data encryption (Computer science)
5
Distributed resources (Electric utilities)
5
Earthquakes
5
Farm produce
5
Fish stock assessment
5
Fishes Conservation
5
Geographic information systems
5
Marine ecosystem management
5
Online social networks
5
Photovoltaic cells Research
5
Photovoltaic power generation Research
5
more ...