Showing posts with label technology. Show all posts
Showing posts with label technology. Show all posts

Friday, October 27, 2017

Counting Raindrops Using Mobile Phone Towers

Mobile Phone Towers

Rainfall – Cellular Telecommunication Networks

Observing rainfall utilising cellular telecommunication networks could offer immense opportunity in reducing loss of life as well as economic loss by improving flood early caution system. This is essentially important in the case of densely populated areas wherein the rainfall information seems to be vital in order to control water management. It is not clear about the precise number of people who died in a series of mudslide on August 14th that had taken place in and the surrounding area of Freetown, the capital of Sierra Leone.

The upper estimate was said to be over a thousand. It is said that the region that had been swept away had not be evacuated mainly since no one was aware how much rain had really fallen earlier, according to rainfall expert Modeste Kacou, at Felix Houphouet-Boigny University in Abidjan in the vicinity of Ivory Coast. Rain devices seem to be scarce in Sierra Leone and satellites tend to identify rainfall in the tropics though estimates for small regions tend to be often inaccurate.

To make matter worse, these numbers tend to be calculated much later after it takes place. Several countries therefore are inclined to utilise cloud-scanning ground radar for measuring precipitation when it takes place though Sierra Leone does not have such radar.

Ivory Coast – Lack Rainfall Radar/Maintenance Cost

Ivory Coast tends to have a double of the GDP per person of Sierra Leone. However like most of West Africa, it tends to lack rainfall radar and maintenance cost would mean that the number of weather stations all over the world has been dropping thus making it difficult to forecast flash floods together with landslides also in some of the rich countries.

Hence it would be useful if some other alternative means of measuring rainfall probably an economical one which has a tendency of employing the prevailing widespread equipment could be formulated. There is such a system which is said to involve mobile-phone networks.The simple understanding is that rain tends to weaken electromagnetic signals.

Several mobile-phone towers particularly those in remote locations utilise microwaves in order to connect with the other towers on the network. A dip in the power of these microwaves tends to expose the presence of rain. The modus operandi does not seem to be as accurate as rooftop rain gauges. However as Dr Kacou points out that as transmission towers seem to be more numerous they seem to report their data automatically and cost meteorologist anything.
Well-Timed/Precise Surface Rainfall Measurement
Well-timed and precise surface rainfall measurements seem to be crucial for water resources management, weather prediction, agriculture, climate research together with ground authentication of satellite-based rainfall evaluations. But most of the land surface of the earth tends to lack this type of data. In several areas of the world, the density of surface rainfall evaluating networks has been quickly decreasing. This progress could probably be stabilized on utilising received signal level data from the huge number of microwave connection used all over the world in commercial cellular communication networks. Together with these types of links, radio signals proliferates from a transmitting antenna at a base station to a receiving antenna at another base station. Rain persuaded reduction and consequently path-averaged rainfall intensity could be retrieved from the attenuation signal between transmitter and receiver. Here it is seen how one network could be utilised in retrieving the space-time dynamics of rainfall for the whole country.

Tuesday, December 10, 2013

Forged in the Fires of Mordor: The Epic History of Welding

Everyone loves a good battle scene in a movie. Whether its William Wallace charging the battlefield with his army of war-painted Scotsmen or the 300 Spartans holding back Xerxes’ army at Thermopylae. We remember the inspiring lines, the epic music, even some of the weapons—how could anyone forget William Wallace’s six-foot long sword? But when we’re engrossed in these magnificent scenes, mouths full of popcorn, we often forget how impressive these ancient weapons were. Without welding, these ancient warriors would have been forced to charge into battle armed only with sticks and stones. But because of the transformative power of welding, these warriors were armed to the hilt with some of the most impressive weapons in history.

Without the luxury of plastic welders that we have today, these ancient civilizations had to be resourceful and innovative in creating welding techniques. The first recorded use of welding occurred around 3000 BC in Egypt—maybe not surprising considering this is the same ancient civilization that built the Great Pyramids. The Egyptians used forge-welding to create bronze and iron weaponry that replaced wooden throwing sticks and stone-tipped arrows.

Welding as we know it today was not invented until the 1800s, but this ancient technique of pressure or solid-state welding allowed metals to be heated in a charcoal fire and then shaped and molded with repeated hammer blows. Solid-state welding doesn’t heat metals to the melting temperature, but the pressure of the hammering does allow two different metals to be joined and create a compound weld that is stronger than either individual metal.

The strength of these metal weapons gave the ancient Egyptians an enormous military advantage over armies that lacked welding technology. Wood doesn’t fare well against iron on the battlefield, and this was extremely influential in Egypt’s ability to conquer surrounding regions and grow as an empire.

Some of the major weapons utilized by the ancient Egyptians were the Khopesh and the battle axe. The Khopesh, also known as the Sickle Sword, was a crescent shaped sword featuring a thick blade with a hook on one end. The hook allowed Egyptian warriors to grab enemy shields to make them vulnerable for stabbing or slashing. This brutal but powerful weapon is the one most often associated with ancient Egyptian armies. Battle axes could be used for hacking or throwing and featured curved blades attached to long handles. These weapons were effective in breaking through shields in hand-to-hand combat. Bronze and iron spears and arrowheads also gave the Egyptians a competitive advantage over their ancient counterparts. Combine these powerful weapons with the speed of chariots, and you have an army that couldn’t be stopped on the battlefield.

However, the Egyptians weren’t the only ancient civilization that employed welding techniques to craft metal weaponry, jewelry, and utensils. The Sumerians, Persians, Greeks, and even the ancient Irish, utilized forge-welding to create intricate gold and silver boxes, goblets, bowls, and royal finery. Ancient welding techniques can be found depicted in wall paintings in Thebes, and archaeologists have discovered artifacts in ancient tombs and pyramids that provide evidence of welding and soldering. So next time you watch an epic battle scene, take a moment to admire the innovation of these ancient civilizations that literally shaped history by forging and welding metals.

Ella Gray is a happy home maker who's home renovation has brought her down some crazy learning paths.  In the process she has developed a special love for welding and the history thereof.  Please feel free to contact her at ella.l.gray@gmail.com.