To prevent measles, children (and some adults) should be vaccinated with the measles, mumps, and rubella (MMR) vaccine. Two doses of this vaccine are needed for complete protection.Children should be given the first dose of MMR vaccine at 12 to 15 months of age.The second dose can be given 4 weeks later, but is usually given before the start of kindergarten at 4 to 6 years of age.o prevent measles, children (and some adults) should be vaccinated with the measles, mumps, and rubella (MMR) vaccine. Two doses of this vaccine are needed for complete protection.
GPS (Global Positioning System) Satellites orbit the earth and transmit signals. GPS receivers take the signal information and use it to calculate the userâs exact geographic location. Most mobile phones and smartphones have GPS receivers. Camcorders and digital cameras also use them for GPS tagging.resent to your audience. 1  Invited audience members will follow you as you navigate and present. 2  People invited to a presentation do not need a Prezi account. 3  This link expires 10 minutes after you close the presentation.
This particular kind of GPS is called assisted GPS (AGPS), and there are several levels of assistance used. GPS A normal GPS receiver listens to a particular frequency for radio signals. Satellites send time coded messages at this frequency. Each satellite has an atomic clock, and sends the current exact time as well. The GPS receiver figures out which satellites it can hear, and then starts gathering those messages. The messages include time, current satellite positions, and a few other bits of information. The message stream is slow - this is to save power, and also because all the satellites transmit on the same frequency and they're easier to pick out if they go slow.