FishXing Software and Learning Systems for Fish Passage Through Culverts
US Fish and Wildlife Service computer tools to assist in design and evaluation of culverts for fish passage. FAQ, downloads, bibliography of related technical papers, and other resources on the topic.
http://www.stream.fs.fed.us/fishxing

Avon Barrier Company
We offer a wide range of vehicle and pedestrian access control systems such as parking barriers, road blockers, gate systems, turnstiles, high security equipment and revenue systems
http://www.avon-barrier.co.uk/

EU Trade Barriers Kill
A study demonstrating how the trade barriers of EU affect the poor countries, published by the Centre for the New Europe.
http://www.cne.org/pub_pdf/2003_09_04_EU_barriers_kill.pdf

Barriers & Bollards Limited
Bollards, Bollard Systems, Steel Bollards, Security Bollards by Barriers and Bollards Limited, manufacturers, suppliers and installers.
http://www.barriersandbollards.com/

Tunneling
Addresses the phenomenon of quantum tunneling. Presents animations of the scattering of a particle from two-dimensional potential barriers and wells, as well as from barriers with slits.
http://rugth30.phys.rug.nl/quantummechanics/tunnel.htm

Flood Barriers
flood panels and flood barriers of lightweight aluminum offer economical flood protection and meet FEMA standards
http://www.floodbarriers.net/

Newgate
Newgate are an experience secured access company who specialise in the design, manufacture and fitting of security gates, traffic barriers, road blockers and sliding gates
http://www.newgate.uk.com/

Metalith
Metalith anti-ram vehicle barriers and blast mitigation barrier walls are designed to protect critical assets with customized force protection. Learn more about our K12 certified perimeter security barriers.
http://www.themetalith.com/

Flood Barriers and Flood Defence Schemes
Flood Control provide a complete range of flood protection products, flood defence designs and flood alleviation schemes.
http://www.floodcontrol.co.uk/

Secure Passage LLC
Offers an enterprise application that provides visibility to and control of network changes, configurations, and performance of firewalls and other appliances.
http://www.securepassage.com/