UFC 4-021-02NF
27 September 2006
change 1, 23 October 2006
electromagnetic field of one device disrupts, impedes, or degrades the electromagnetic
field of another device by coming into proximity with it. With ESS, devices are
susceptible to EMI because electromagnetic fields are a byproduct of the passing
electricity through a wire. Data lines that have not been properly shielded are
susceptible to EMI. A good example of an ESS application is using shielded wiring from
a field card reader back to the local ACS panel.
False Acceptance Rate (FAR). The rate or percentage at which a false credential is
inaccurately accepted as being valid by an ACS. A sample FAR for a product could be
0.1%.
False Alarm. An alarm when there is no alarm stimulus.
False Rejection Rate (FRR). The rate or percentage at which an ACS product or
system rejects an authorized credential holder.
Frame Rate Per Second (FPS). When referring to CCTV video image, this term refers
to how often the visual still image is being updated. Most movies at the cinema operate
at thirty fps. Recommended values for alarm and non-alarm CCTV video fps are
provided in the CCTV technical section of the document.
Intrusion Detection System (IDS). A system consisting of interior and exterior
sensors, surveillance devices, and associated communication subsystems that
collectively detect an intrusion of a specified site, facility, or perimeter and annunciate
an alarm.
Local Area Network (LAN). A geographically limited data communication system for a
specific user group consisting of a group of interconnected computers sharing
applications, data and peripherals.
Liquid Crystal Display (LCD). A type of display used for ESS monitors and other
applications. LCDs utilize two sheets of polarizing material with a liquid crystal solution
between them. An electric current passes through the crystals to align so that light
cannot pass through them. Each crystal, therefore, is like a shutter, either allowing light
to pass through or blocking the light. LCD displays can be monochrome or color.
Monochrome displays are typically blue or dark gray images on top of a grayish-white
background.
transmission/storage medium. With old VHS tape systems, the term referred to the
storage of four different CCTV camera recordings onto a single VHS tape. With current
technology, it is sometimes used to refer to transmission media. For example, a bigger
transmission line can be used to bring back six door contact signals from a remote site
to a centralized facility on one line as opposed to six different lines. The end result of
multiplexing on transmission media is construction cost savings of installing less
conductors.
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