Articles Written by Instrom Ltd From Isnare.com http://www.isnare.com/?s=author&a=Instrom+Ltd Ten Point Guide To The Successful Procurement Of Security Systems Business Management Instrom Ltd Sun, 24 Dec 2006 00:00:00 +0800 http://www.isnare.com/?aid=112302&ca=Business+Management 1.Consider your security requirements early In the life cycle of a major project it is never too early to consider security requirements. It is all too common for a major development or building to be designed and then for a security consultant or contractor to be approached to design security syste... Glossary Of Terms (A-C) - CCTV Computers and Technology Instrom Ltd Thu, 30 Nov 2006 00:00:00 +0800 http://www.isnare.com/?aid=105436&ca=Computers+and+Technology AC Alternating Current ACCESS CONTROL SYSTEM Electronic system used to allow, restrict and track the movement of people through entry/exit points in a site. This is achieved through the use of electronic individual codes, keys or cards etc, to release a locking mechanism. ACTIVITY DETECTION A featur... Glossary Of Terms (D - L) - CCTV Computers and Technology Instrom Ltd Thu, 30 Nov 2006 00:00:00 +0800 http://www.isnare.com/?aid=105442&ca=Computers+and+Technology DARK CURRENT Leakage signal from a CCD sensor in the absence of incident light. DARK NOISE Noise caused by the random (quantum) nature of the dark current. DECIBEL (DB) A logarithmic ratio between two electrical signals or values. Usually refers to power, but can also be used for voltage and current... Glossary Of Terms (M - R) - CCTV Computers and Technology Instrom Ltd Thu, 30 Nov 2006 00:00:00 +0800 http://www.isnare.com/?aid=105443&ca=Computers+and+Technology MAGNIFICATION RATIO The ratio between the focal length of a lens and the focal length of a standard angle lens. Indicates the magnification of the image when compared to an image from a standard angle lens. MANUAL IRIS Type of lens that requires manual focusing. MATRIX SWITCHER Advanced type of swit... Glossary Of Terms (S - Z) - CCTV Computers and Technology Instrom Ltd Thu, 30 Nov 2006 00:00:00 +0800 http://www.isnare.com/?aid=105444&ca=Computers+and+Technology S/N RATIO Signal-to-Noise ratio is calculated with the logarithm of the normal signal and the noise RMS value. SCENE ILLUMINATION The average light level incident upon a protected area. Normally measured for the visible spectrum with a light meter having a spectral response corresponding closely to...