Essay Example on Lorenzo proposed 8 a new WSN Wireless Sensor Network

Lorenzo proposed 8 a new WSN Wireless Sensor Network system for monitoring landslides using Wi MAX The system has three levels i Gateway level manages data aggregation and storage and also coordinate with WSN ii Server Level stores data on remote server iii Node Level Peripheral nodes consists of a sensor board having sensors etc Nodes are placed in landslide area and can make an ad hoc WSN Where a sensor should be placed in a ground is decided by integrating a wideband technology with radar technology it helps in improving the accuracy To reduce the noise Kalman filter is used Sensor nodes are arranged in a hierarchical manner X y and z coordinates of every node is noted day by day to check the daily movement of landslide C Li Fi R Karthika proposes the use of Li Fi in disaster management 14 Li Fi is typically implemented using white LED light bulbs at the downlink transmitter The operational procedure is very simple if the LED is on you transmit a digital 1 if it's off you transmit a 0 visible light is used between 400 THz 780 nm and 800 THz 375 nm as optical carrier for data transmission and illumination in VLC which is the method of wirelessly using rapid pulses of light to transmit information 

Fast pulses of light are used to transmit information wirelessly On one end all the data on the internet will be streamed to a lamp driver when the LED is turned on the microchip converts the digital data in form of light D Zigbee In the proposed system by M Chaitra et al 5 ZigBee is used as a module for remote correspondence in information acquisition along with three sensors The sensors utilized are Soil moisture sensor Humidity sensor and accelerometer sensor When the threshold values are crossed warning would be generated Using zigbee we can communicate at high data rates We can use these ZigBee modules anywhere even in forests mountains because external connection are not required Fig 8 Transmitter Circuit 6 Pranav Pravin Garje et al 6 have examined the sites that were prone to disaster and used sensors over them to detect Connections of sensors to microcontroller N Mote that handles and gathers the data from the sensors N Mote to N Gateway are connected through Zigbee Connection of N Mote to cloud which are connected to internet through wifi or Ethernet is through gateway N Gateway the data is sent to respective organizations rescue teams when the certain threshold is exceeded E Ultra wideband UWB Christian Arnhardt developed of an autonomous sensor network called SLEWS that is suitable for the detection and the observation of mass movements 15 They used special sensors such as inclinometer pressure sensor hygrometer humidity sensors or linear position sensors 

Those sensors have high accuracy for example less than one millimetre Price and accuracy stand in direct relation All these sensors are local sensors with output about local phenomena To get acceptable information about landslides the measuring methods must be accurate to one centimetre Therefore Ultra wide band UWB technologies which promise higher accuracies sub centimetre may be applicable Ultra wide band has the possibility to send information with or without a carrier frequency The absolute bandwidth is more than 500 MHz The relative bandwidth is a quarter of the middle frequency The frequency ranges between 0 1 0 96 GHz and 3 1 10 6 GHz but the information is sent with a low power max 41 3 dBm MHz The maximum range for this method is therefore 50 metres F GPRS Jayant Rajaram et al 16 designed the real time system for landslide detection using 89s52 controller and ATmega328 controller The main component used in this system is zigbee GPRS They attached three sensors like moisture sensor accelerometer rain sensor flex sensor In transmitter section the sensors connected to 89c52 controller Data collected from sensors send to monitoring centre through monitoring host If monitoring host detect any value above threshold value then it send to surrounding resident System requires low power stable processing speed so we use ATmega328 controller zigbee module and also GPRS module available in monitoring host It is communication interface between sensor nodes and monitoring centre During normal operation monitoring host send data to monitoring centre if any sensor detect value above threshold value then GPRS send data to surrounding resident G Satellite An early warning system of four level Zero Outlook Attention and Warning was developed 27 Threshold was chosen through Velocity of the landslide occurrence 

Expert advice and judgement also included to avoid false alarm Devices like rain gauge and moisture content was measured Different sensors like tilt meter etc was used to detect landslide Wireless data transmission was done through satellite while data processing done using different Map and data servers Then warning to the local authority if the level of landslide is high Drawing upon the recent advances of satellite remote sensing technology and landslide modelling techniques a framework is proposed to attempt an early warning system for landslide hazards after heavy rainfall and or earthquake the two major triggers for landslides 20 This framework includes three major components landslide prone area information database including geology elevation topography soil and land cover types secondly a real time space borne precipitation estimation system and lastly a near real time ground shaking prediction system after earthquakes To achieve good results the main aim is to get early warning before the disaster so that lives could be saved