Cisco Cisco Aironet 1522 Lightweight Outdoor Mesh Access Point 정보 가이드
MIDLAND, TEXAS is located in the heart of the
oil and gas rich Permian Basin. In 2005 the
City began to experience exponential growth
as the national and global demand for energy
soared and exploration and production
activates increased. The population of about
100,000 began growing 10% annually. In 2007
year over year traffic volume at major arterials
in the City increased by 17% and traffic
management became a top priority.
oil and gas rich Permian Basin. In 2005 the
City began to experience exponential growth
as the national and global demand for energy
soared and exploration and production
activates increased. The population of about
100,000 began growing 10% annually. In 2007
year over year traffic volume at major arterials
in the City increased by 17% and traffic
management became a top priority.
The City’s existing traffic management system
installed in the early 1990s was at end-of-life.
It had been installed as two separate systems.
Major arterials were managed by fixed time
intervals for peak inbound and outbound traffic
flows. The downtown system was controlled by
a grid and changed traffic signals at fixed
intervals set independently for inbound and
outbound traffic, and by time of day.
Replacement parts were scarce and operations
and maintenance costs were increasing due to
the need for more manual intervention. The
decision to assess options and select an
advanced traffic management system (ATMS)
was initiated by Gary Saunders who heads the
City Traffic Engineering Department.
It had been installed as two separate systems.
Major arterials were managed by fixed time
intervals for peak inbound and outbound traffic
flows. The downtown system was controlled by
a grid and changed traffic signals at fixed
intervals set independently for inbound and
outbound traffic, and by time of day.
Replacement parts were scarce and operations
and maintenance costs were increasing due to
the need for more manual intervention. The
decision to assess options and select an
advanced traffic management system (ATMS)
was initiated by Gary Saunders who heads the
City Traffic Engineering Department.
Wireless is the solution
Saunders recommended the IP wireless ATMS
proposed by Naztec, Inc. The solution used the
Naztec model 980 controller and the web-based
ATMS Central Software Suite running on a Cisco
wireless
proposed by Naztec, Inc. The solution used the
Naztec model 980 controller and the web-based
ATMS Central Software Suite running on a Cisco
wireless
network.
In
2008
the
traffic
department began working with Naztec and
Coleman Technologies Inc., a Cisco Gold
partner, to handle the site survey, final design
and implementation.
Coleman Technologies Inc., a Cisco Gold
partner, to handle the site survey, final design
and implementation.
The re-vamped city-wide system began
operation at the beginning of March this year
using 180 Cisco 1524 wireless access points.
Licensed frequencies are used to provide the
backhaul for the 200Mbps network and provide
two way communications with the Naztec
controllers.
using 180 Cisco 1524 wireless access points.
Licensed frequencies are used to provide the
backhaul for the 200Mbps network and provide
two way communications with the Naztec
controllers.
The system monitors, manages, and notifies
the traffic department about the status of 119
networked traffic signals and 70 pedestrian
crosswalk flashers. An additional 29 solar
powered flashers will be added when the
department identifies the best solution to
power both the radios and the flashers. The
system backbone runs to a new centralised
Traffic Management Centre (TMC) that was
implemented as part of the project.
networked traffic signals and 70 pedestrian
crosswalk flashers. An additional 29 solar
powered flashers will be added when the
department identifies the best solution to
power both the radios and the flashers. The
system backbone runs to a new centralised
Traffic Management Centre (TMC) that was
implemented as part of the project.
Arterial management applications use the IP
network to detect traffic flow and then take
rapid
rapid
pre-emptive
action
to
mitigate
congestion. IP-connected controllers send
immediate notification of signal malfunction
and enable remote management to resolve
signalling problems, optimise traffic flow by
changing signal offsets and splits, and adjust
the traffic signals for major events affecting
traffic.
immediate notification of signal malfunction
and enable remote management to resolve
signalling problems, optimise traffic flow by
changing signal offsets and splits, and adjust
the traffic signals for major events affecting
traffic.
Secure monitoring and management can be
done via web-enabled devices at the intersec-
tions and connected in what is effectively an
extended wireless LAN. This permits traffic
polices which can be programmed to respond
tions and connected in what is effectively an
extended wireless LAN. This permits traffic
polices which can be programmed to respond
to predefined conditions. For example, a vehicle
threshold policy could be set for key intersec-
tions. When the count exceeds the threshold
the system can recalculate signal splits and
offsets and automatically apply them.
threshold policy could be set for key intersec-
tions. When the count exceeds the threshold
the system can recalculate signal splits and
offsets and automatically apply them.
‘By having the automated system analyze
issues, I estimate that we will be able to reduce
the amount of time spent on troubleshooting
and problem resolution by at least 30%.
the amount of time spent on troubleshooting
and problem resolution by at least 30%.
‘By reducing manual intervention, we also
reduce fuel costs for the City. Motorists will
experience fewer delays, reducing carbon
emissions and enabling drivers to gain better
fuel mileage. Collectively these savings
translate in to millions of dollars a year’ says
Gary Saunders, City of Midland transportation
manager.
experience fewer delays, reducing carbon
emissions and enabling drivers to gain better
fuel mileage. Collectively these savings
translate in to millions of dollars a year’ says
Gary Saunders, City of Midland transportation
manager.
Mr Saunders estimates the following cost
savings and benefits as a result of the new
ATMS: 27% reduction in total delays per
vehicle, 18% reduction in total stops per
vehicle and 10% reduction in fuel consump-
tion. This adds up to $1.2m annual savings on
four major arterials alone with average
vehicular volume. Following the first three
months of operation, actual values appear to
be in line with these estimates.
ATMS: 27% reduction in total delays per
vehicle, 18% reduction in total stops per
vehicle and 10% reduction in fuel consump-
tion. This adds up to $1.2m annual savings on
four major arterials alone with average
vehicular volume. Following the first three
months of operation, actual values appear to
be in line with these estimates.
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Wireless traffic management
network for downtown renewal
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'industrial ethernet book':
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