Chair pressure mat is a system design to monitor the change in pressure when people get out of chairs. This product description is meant for all people using pressure chairs in their homes, places of work, hotels etc. It is also meant for all suppliers and manufacturers of pressure chairs.
Chair pressure mat is an air operated system which controls the change on the mat when a person gets out of a chair. To minimize false alarm of the system, the system will only be activated when a meaningful change in pressure is achieved. Activation of the system will only occur when some of the individual’s weight is transferred to their feet when he or she gets out of the chair. The advantage of this system is that, it can be moved comfortably and easily among different chairs in the room. It is a battery operated system hence they can be removed or switched off when the system is not in use. Additionally, the system can be used on holiday since it does not need main power connection; therefore, one will just need to buy batteries and use the system while on holiday.
The main components of the system are sensor, small circuit, cables and the mat. The sensor is used to sense an individual’s weight enabling the small circuit to make a suitable signal like that of a standard call system. Cables are used to power the system and also to transmit the signal to the calling system. The mat is placed on the chair where the individual will sit on it. With the system connected to a standard call system there is no need of using the batteries in the system. The advantage of this system is that it allows chairs fixed with sensors be moved within the room without wires being trailed. The mat is waterproof and 25cm by 37cm by 4cm thick in size. It is also compatible with all the current calling system.
Interlaced Scanning process
The interlaced scanning is the scanning process where a frame is created using two frame fields. During scanning, odd lines are scanned and reproduced first resulting to one field (the first field) and the other field is created by even lines, which are placed in the spaces betwixt the lines of the first field. 60 fields per second are scanned by a television with 30 even and 30 odd fields created. A standard in television broadcasting is that the two fields are combined for every 1/30 of a second to create a frame; hence, 30 frames are created per second. For interlaced scanning to be successful, the picture or frame which consists of 525 lines is divided into two fields of 262.5 lines each. These fields are scanned alternatively so that the whole picture area is covered.
To scan the first field, the electronic scan beam is positioned at the left top of the screen where it trances the first line with the help of horizontal sync pulses from the horizontal deflection circuits. Once the first line is scanned, the scanning beam is rapidly moved to the second line being guided by the line fly back. Using the vertical synch pulses the beam is correctly positioned on line and scanned. This process is repeated for the fields and hence creating a frame consisting of two fields. Once the scanning of the second field is completed, the beam is usually taken back to the point at which the scanning of the first field starts. The process allows half of the picture to appear on the screen at a time, and the other half appears a moment later (precisely 1/60th of a second).