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Smart carpet..................detects falls and strange footsteps

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Smart carpet detects falls and strange footsteps A team at the University of Manchester in the UK has developed a carpet that can detect when someone has fallen over or when unfamiliar feet walk across it. Optical fibres in the carpet's underlay create a 2D pressure map that distorts when stepped on. Sensors around the carpet's edges then relay signals to a computer which is used to analyse the footstep patterns. When a change is detected - such as a sudden stumble and fall - an alarm can be set to sound. By monitoring footsteps over time, the system can also learn people's walking patterns and watch out for subtle changes, such as a gradual favouring of one leg over the other. It could then be used to predict the onset of mobility problems in the elderly, for example. The carpet could also be used as an intruder alert, says team member Patricia Scully . "In theory, we could identify footsteps of individuals and the shoes they are wearing," she says. But...
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Code of practice for power system protection

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Code of practice for power system protection netic Relay 01 The entire wiring of circuitry for indications, alarms, metering and protection should be permanent wiring. 02 The leads should be marked and identified by ferrules near terminals. 03 Every lead should end at a terminal point and no junction by twisting is allowed. 04 The wiring should be by copper leads for C.T secondary for all cores i.e. metering cores as well as protection cores and for PT secondary for protection core. 05 The wiring should be by copper leads 1.07 The copper lead for 1.05 & 1.06 above should be stranded but not single lead type. 06 Aluminum leads can be used for indication, alarms and PT secondary for metering but stranded wires only are to be used. But copper leads are always preferable for these said purposes. 07 The terminations should be lugged by ring shape ‘O’ lugs. ‘U’ shape lugs should be avoided since ‘U’ shape lugs may slip if terminal is loosen. 08 For CT Secondary terminations, two nuts wit...
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Vector Group of Power-Transformer-Winding connection designations

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                             Basic Idea of Winding An ac voltage applied to a coil will induce a voltage in a second coil where the two are linked by a magnetic path. The phase relationship of the two voltages depends upon which ways round the coils are connected. The voltages will either be in-phase or displaced by 180 degree. When 3 coils are used in a 3 phase transformer winding a number of options exist. The coil voltages can be in phase or displaced as above with the coils connected in star or delta and, in the case of a star winding, have the star point (neutral) brought out to an external terminal or not. Six Ways to wire Star Winding : Six Ways to wire Star Winding Six Ways to wire Delta Winding : Six Ways to wire Delta Winding Polarity An AC voltage applied to a coil will induce a voltage in a second coil where the two are linked by a ma...
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