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Application of Drones with Variable Area Nozzles for Effective Smart Farming Activities
Published in Saravanan Krishnan, J Bruce Ralphin Rose, N R Rajalakshmi, Narayanan Prasanth, Cloud IoT Systems for Smart Agricultural Engineering, 2022
J. Bruce Ralphin Rose, V. Saravana Kumar, V.T. Gopinathan
There are a variety of sensors used to provide the necessary information/input to the microcontrollers. They are: (i) location-based Sensors, (ii) electrochemical sensors, (iii) temperature or humidity sensor, (iv) optical sensor, and (v) multispectral sensors. Here, location-based sensors are used for locating the different areas and spots in the agriculture fields [8, 24]. Normally, GPS receivers are used for finding the longitude and latitude of a particular point on the earth's surface with the help of a GPS satellite network. These smart location sensors play an important role in PA by pointing out the location in the fields for monitoring the growing crops toward effective watering, fertilization, and treatment of weeds.
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Published in Cesar Barrios, Yuichi Motai, Predicting Vehicle Trajectory, 2017
This research is based on the use of a GPS receiver to obtain location information and to be able to estimate the projected path for a vehicle; so, selecting a good GPS receiver was of utmost importance. The Holux GR-213 1 Hz GPS receiver used in this research is wide area augmentation system (WAAS) enabled. The WAAS is a system developed for civil aviation by the Federal Aviation Administration (FAA) in conjunction with the U.S. Department of Transportation (USDOT). It is a nationwide differential GPS system where base stations with fixed receivers calculate and transmit the GPS error to the geostationary satellites in its view, which in turn broadcast the corrections that can be used by individual WAAS-capable GPS receivers. Its accuracy is less than 3 m 95% of the time, and the GPS receiver used claims to have an accuracy of less than 2.2 m [22].
The engineering environment
Published in Mike Tooley, Engineering A Level, 2006
Another example of technological development is that of the Global Positioning System (or GPS). GPS is a collection of satellites owned by the U.S. Government that provides highly accurate, worldwide positioning and navigation information, 24 hours a day. It is made up of 24 NAVSTAR GPS satellites that orbit 12,000 miles above the Earth, constantly transmitting the precise time and their position in space. GPS receivers on (or near) the surface of the earth, listen in on the information received from three to twelve satellites and, from that, determine the precise location of the receiver, as well as how fast and in what direction it is moving.
Estimating Leaf Area Index and biomass of sugarcane based on Gaussian process regression using Landsat 8 and Sentinel 1A observations
Published in International Journal of Image and Data Fusion, 2023
Gebeyehu Abebe, Tsegaye Tadesse, Berhan Gessesse
In this study, in-situ LAI and biomass measurements were conducted six times over the three growth stages (i.e., tillering and canopy development, grand growth, and maturity); in parallel with the image acquisition dates. Image acquisition dates, sensor characteristics and field visit dates was showed in detail by the study of Abebe et al. (2022). Field visit dates were scheduled by considering the dates closer to the Landsat 8 (L8) and Sentinel 1A (S1A) satellite overpass over the study area and then in-situ measurements were conducted. The weather conditions during the dates of field measurements and the satellite overpass over the study area were ideal with few clouds. Altogether, 80 samples were collected in the study area. The geographic coordinates of each sample plot were recorded by Garmin GPS 72. Garmin GPS receivers are accurate to within 10 m under normal conditions (Drosos and Malesios 2012) and horizontal accuracy of less 3 m was obtained in this study. For each sample plot, we measured the plant parameters of sugarcane, including leaf length, leaf width, plant density, plant height and biomass.
A Survey of National Disaster Communication Systems and Spectrum Allocation - an Indian Perspective
Published in IETE Technical Review, 2020
Shrayan Das, Kirtan Gopal Panda, Debarati Sen, Wasim Arif
Unavailability of satellite-based distress alert systems had plagued the Indian Coast Guard for decades causing hindrances to maritime rescue operations during cyclones, tsunamis etc. This prompted the Space applications Center of ISRO to develop and design the Distress Alert Transmitter (DAT) [9] with support from indigenous private industries. During emergencies, the DAT transmits a short message containing the device position and type of emergency to a central processing center through satellites, thereby initiating rescue efforts. The transmitter operates in 402.65–402.85 MHz band and is linked with the INSAT-3A system to provide round the clock surveillance. It has the following features: The transmitter is lightweight, compact, portable, floatable, battery operated and hence suitable for marine environments.It has an inbuilt GPS receiver capable of providing accurate location and time information.In case of an emergency, the user manually activates the transmitter and an emergency message along with the user's location is relayed to a Central Station through the INSAT network.Once activated, it can transmit in random mode at regular intervals of 1 minute for 5 minutes followed by retransmission every 5 minutes. Depending on the available power source, transmission can last up to 24 hours.The transmitter uses omnidirectional antenna having hemispherical coverage that can be easily mounted on small boats, and is powered by a lithium primary battery (7.2 V/3.2 Ah) for steady operation and prolonged connectivity.
An assessment on the use of stationary vehicles to support cooperative positioning systems1
Published in International Journal of Control, 2018
Rodrigo H. Ordóñez-Hurtado, Emanuele Crisostomi, Robert N. Shorten
Accuracy levels of less than 3.5 m have been reported for high-quality GPS receivers at a given surveyed benchmark (Hughes, 2014). Our choice of σGPS = 6 m follows experimental results using commercial receivers in real-world settings (Schipperijn et al., 2014).