Signaling central station

Intruder alarms are designed to give a warning of the presence of an intruder within or attempting to enter the protected area. Alarm systems may act as a deterrent to the casual or opportunist thief but they will do little or nothing to prevent a determined intrusion, and to be effective they must provoke an early response from the appropriate authority (in most cases the police). The warning may be a local audible device, but normally the alarm signal is transmitted by the telephone network to a central station operated by a security company on a 24-hour basis. 

In contrast to systems that are set up to transmit local only alarms when the sensors are triggered, systems can also be set up to transmit signals to a central location, such as to a control room or guard post at the utility, or to a police or fire station. Most fire/smoke alarms are set up to signal both at the location of the event and at a fire station or central monitoring station. Many insurance companies require that facilities install certified systems that include alarm communication to a central station. For example, systems certified by the Underwriters Laboratory (UL) require that the alarm be reported to a central monitoring station. 

Packaged units have traditionally had their own progranunable logic controllers (PLCs) and local control panels. This is especially true in the case of units that require extensive sequence controls for stepwise processes such as filtration and ion exchange. Many operators find it more convenient to have control supervised from a central station. From this point of view, these systems are better controlled by a distributed control system (DCS) and monitored from the control room. Some who bought systems equipped with PLCs some years ago have dispensed with the PLCs and moved control to the DCS. Many favor systems which combine local control by PLC with status and alarm signals sent to the DCS. 

Central Station Systems. Central station systems are operated by firms whose principal business is the furnishing and maintaining of supervised signaling service. The central station... 

All detection systems require some t) e of human intervention. Common surveillance systems include local, remote station, proprietary and central station signaling. The local system is basically the water motor gong or local electric bell. These will ring at the riser with retransmission to other parts of the facility. It is a crude surveillance system for a semiconductor facility but it is a necessary part of every sprinkler system. 

Remote Station. Remote station signaling is not as common today as it once was. With the new technology in central station and proprietary systems, there is little need for this type of signaling. The theory behind this system is that it is supervision provided by a third party without the certification or listing of that third party. An extensive review of equipment and services is needed before it should be considered satisfactory supervision. 

Central Station. The central station supervisory system has been the norm in the semiconductor industry. The size of the semiconductor facility warrants the reliability that comes with this level of protection. Equipment is specifically listed for this type of service. Signals from the devices are sent to a remote location approved by Factory Mutual or listed by Underwriters Laboratory. Upon receipt of a fire signal, a central station must alert the fire department. 

Many medical devices contain alarms including electrocardiogram machines, pulse devices, and blood pressure monitors. Other devices include bedside telemetry, central station monitors, infusion pumps, and ventilators. These alarm-equipped devices help provide safe care to patients. Alarms can produce similar sounds and can cause confusion. Alarm signals per patient per day can reach several hundred, depending on the unit within the hospital. Most alarms do not require clinical intervention. Clinical personnel can become desensitized and can suffer a type of fatigue. Major patient safety events can occur and the following alarm issues can contribute to the incident ... 

The utilized earthquake catalog was collected by the Central Weather Bureau (CWB) and provided earthquake parameters for events from 1900 to 2010 in Taiwan. Prior to 1973, a total of 15 stations equipped with Gray-Milne, Wiechert, or Omori seismographs were maintained. After 1973, the Taiwan Telemetric Seismic Network (TTSN) was established. The TTSN consists of 25 stations within the region of Taiwan, fri the TTSN network, real-time signals are transmitted from field stations to a central station via leased telephone lines. 

An alarm system consists of sensors that detect different types of events an arming station that is used to turn the system on and off a control panel that receives information, processes it, and transmits the alarm and an annunciator that generates a visual and/or audible response to the alarm. When a sensor is tripped it sends a signal to a control panel, which triggers a visual or audible alarm and/or notifies a central monitoring station. A more complete description of each of the components of an alarm system is provided below. 

A control panel receives information from the sensors and sends it to an appropriate location, such as to a central operations station or to a twenty-four-hour monitoring facility. Once the alarm signal is received at the central monitoring location, personnel monitoring for alarms can respond (such as by sending security teams to investigate or by dispatching the fire department). 

Automated detection and protection systems to signal at an offsite central alarm station service for continuous monitoring. 

Intracellular signal transduction employs central switching stations that receive, modulate and transmit signals further. The Ras proteins (also known as p2T proteins) make up a switching station of particular importance for growth and differentiation processes. The Ras proteins process signals received by receptor tyrosine kinases, by receptors with associated tyrosine kinase activity and by G-protein-coupled receptors, and transmit these into the cell interior (Fig. 9.1). 

Fig. 9.1. The Ras protein as a central switching station of signaling pathways. A main pathway for Ras activation is via receptor tyrosine kinases, which pass the signal on via adaptor proteins and guanine nucleotide exchange factors to the Ras protein. Activation ofRas protein can also be initiated via G-protein-coupled receptors and via transmembrane receptors with associated tyrosine kinase activity. The membrane association of the Ras protein (see Fig. 9.6) is not shown for clarity. In addition, not aU signahng pathways that contribute to activation of the Ras protein are shown, nor are all effector reactions. Py omplex of the heterotrimeric G proteins GAP GTPase activating protein GEF guanine nucleotide exchange factor.

Ras protein is a central switching station in intracellular signal transduction, which receives, modulates and passes signals on. The Ras protein receives, in particular, signals promoting growth and differentiation, which start from activated receptor tyro-... 

Fig. 10.1. Principle of signal transduction through intracellular protein kinase cascades. The intracellular protein kinase cascades are organized in modules composed in most cases of three proteinkinases and a scaffold protein. The modules process signals that are registered, integrated and passed on at the inner side of the cell membrane by central switching stations such as the Ras protein or the Rac protein. In the case of the MAP kinase pathway, the cascade includes at least three different protein kinases. Specific regulatory processes may take effect at every level of the cascade in addition, signals may be passed from the different protein kinases to other signaling pathways.

The flexibility of electrons and nuclei in a molecule depends on their mutual distance. If the distance is small, an external field has a smaller influence on the particles than if the distance is large. Therefore, the polarizability of a molecule can be modulated by a vibration. Consequently, the induced dipole moment and therefore also the amplitude of the emitted field are modulated by the frequency of the vibration. The molecule behaves like the radio antenna of an AM station, which emits signals produced by amplitude modulation of a certain carrier frequency with a signal frequency i s (Fig- 2.4-4). Analysis of the emitted field with a spectrometer shows a central frequency as well as side bands at a distance of cm. According to the Boltzmann distribution, a side band with a lower frequency emitted by a molecule has a higher intensity than the side band with the higher frequency. 

Manual Signaling.—This is of greatest use in extensive pyrometer installations having a central pyrometer station for indicators and recorders. Signals... 

For most of the stations shown in Fig. 12.12 times series have been established for POC and PON and for DOC and DON. As an example, time series are shown in the surface layer (Fig. 12.13) and bottomlayer (Fig. 12.14) of station 271 in the central Eastern Gotland Basin. POC and PON concentrations near the surface show a pronounced seasonal signal with maximum summer concentrations close to 50 pmol/l C for POC and 5 pmol/1 N for PON. The minimum in winter is below 10 pmol/1 C for POC and below 2 pmol/1 N for PON, respectively. The time series of nitrogen species also reveals that DIN, which accumulates during wintertime, is almost completely converted into PON during plankton blooms in summer (Fig. 12.13 below). 

The remote characteristic of PAT allows QC/QA personnel to simultaneously monitor a number of experiments or tests. The reviewer sits at a central monitoring station that is receiving data from several manufacturing lines or laboratory processes. A well-designed display with built in warning signals can allow eflScient review from a variety of stations. 

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