9184 results about "False alarm" patented technology

An adaptive alarm system is responsive to a physiological parameter so as to generate an alarm threshold that adapts to baseline drift in the parameter and reduce false alarms without a corresponding increase in missed true alarms. The adaptive alarm system has a parameter derived from a physiological measurement system using a sensor in communication with a living being. A baseline processor calculates a parameter baseline from a parameter trend. Parameter limits specify an allowable range of the parameter. An adaptive threshold processor calculates an adaptive threshold from the parameter baseline and the parameter limits. An alarm generator is responsive to the parameter and the adaptive threshold so as to trigger an alarm indicative of the parameter crossing the adaptive threshold. The adaptive threshold is responsive to the parameter baseline so as to increase in value as the parameter baseline drifts to a higher parameter value and to decrease in value as the parameter baseline drifts to a lower parameter value.

A system and method for enabling a central station to accurately verify in real-time whether an alarm signal generated by a security base station is a false alarm, and for enabling remote users to securely access features of the security base station such as remote surveillance, activating and deactivating the system, and adjusting alarm sensitivities.

A security system that secures a building includes a weather detector for detecting weather conditions, such as thunder or high winds, which are likely to cause false alarms in sensors such as an acoustic glass break sensor, shock sensor and vibration sensor. The weather detector may include a sensing component that senses atmospheric conditions external to the building, such as temperature, pressure, wind speed and / or lightning. The weather detector may also include a component for receiving a data communication, such as from a radio, Internet, or telephone link, indicating that the weather condition is present in a vicinity of the building. The security system operates in a bad weather mode by requiring corroboration of intrusion detection signals from the sensors that can cause false alarms.

A baggage scanning system and method employ combined angular and energy dispersive x-ray scanning to detect the presence of a contraband substance within an interrogation volume of a baggage item. The interrogation volume is illuminated with penetrating, polychromatic x-rays in a primary fan beam from a source such as a tungsten-anode x-ray tube. An energy-dependent absorption correction is determined from measurement of the attenuation of the fan beam at a plurality of different energies. Radiation coherently scattered by substances in the interrogation volume is detected by an energy-resolved x-ray detector operated at a plurality of scattering angles to form a plurality of scattering spectra. Each scattering spectrum is corrected for energy-dependent absorption and the corrected spectra are combined to produce a scattering pattern. The experimental scattering pattern is compared with reference patterns that uniquely characterize known contraband substances. The system and method can locate and identify a wide variety of contraband substances in an accurate, reliable manner. The system provides for automated screening, with the result that vagaries of human performance are virtually eliminated. False alarms and the need for hand inspection are reduced and detection efficacy is increased.

The present invention is directed to providing systems and methods for remotely monitoring sites to provide real-time information which can readily permit distinguishing false alarms, and which can identify and track the precise location of an alarm. In embodiments, monitoring capabilities such as intrusion / fire detection and tracking capabilities, can be implemented through the use of multistate indicators in an interface which permits information to be transmitted using standard network protocols from a remote site to a monitoring station in near real-time. In embodiments, communications can be handed from the centrally located host monitoring station to a mobile monitoring station (for example, a laptop computer in a responding vehicle, such as a police or fire vehicle). Additional embodiments include the measurement of environmental parameters such as temperature, carbon monoxide and differential air pressure to detect, monitor and manage a fire event. These measurements along with selected controllable output devices deployed in a space, such as sprinkler control valves and individually or zoned sprinkler heads, are used to initiate and control fire suppression technology both locally and remotely. For instance, a system of the present invention may detect a fire and cause a sprinkler system to disburse water in a facility.

The invention relates to the technical field of monitoring of plunger pumps, in particular to a method for preventing evacuation of a plunger pump based on monitoring of the output pressure. The method relates to the plunger and an output pipeline, and is characterized in that a pressure data acquisition control device is arranged on the outlet pipeline; and a data processing method comprises the following steps that (1) the average value P0 of the output pressure is obtained, specifically, the output pressure setting tolerance delta P is set, the domain above a P0+delta P line is called a peak domain, and the domain below a P0-delta P line is called a valley domain; a peak domain counter A and a valley domain counter B are set correspondingly; the allowable difference value between the peak domain counter A and the valley domain counter B is the numerical value C; and an out-of-tolerance time counter D and an upper limit E are set; (2) pressure data Px is acquired; (3) abnormal data are removed; (4) the number of times of Px falling into the peak domain and the valley domain is calculated; and (5) whether the out-of-tolerance time D of the difference value between the peak domain counter A and the valley domain counter B exceeds a preset value E or not is judged, and if yes, an evacuation alarm is given out. Compared with a detection method in the prior art, the method is accurate and reliable, and false alarms are avoided.

Communication systems and methods that mitigate false alarms due to Doppler shift are disclosed. Received message data is mapped to orthogonal Walsh codes, interleaved and scrambled with appropriate PN sequence prior to transmission. The transmitted message data is descrambled and deinterleaved upon reception. The energies associated with each of the Walsh code from various antennas and / or signal paths are combined to obtain a total energy for each Walsh code. If the total energy of the Walsh code exceeds a certain threshold it is declared as the received message else an erasure is indicated. As the data is interleaved prior to transmission, any phase ramp introduced due to Doppler is transformed into random phase errors upon deinterleaving at the receiver thereby mitigating false alarms.