Tracfone Smartphone

A permanent station GNSS reference RTK radio can transmit data directly to RTK receivers. The station will be monitored by a program running on a computer and will also allow the downloading and archiving of recorded data. Working radius of about 30 km is usually sufficient in this case and provides accuracies required. In special cases you can install a second or more permanent stations GNSS reference in order to ensure the attainment by two independent positions RTK receivers for determining certain critical points. In this case one computer (server) can provide control for all permanent stations GNSS reference.


To ensure accuracy centimeter networks Geodetic created by observation satellite, use and currently permanent stations temporarily, by installing a receiver in a network point and keep it fixed over several work sessions, or even for a whole day of observation. For relative positioning with high precision observations were used only in a situation where measurements were held near these stations in order to ensure control over the base length dependent bias. When designing permanent reference station networks GNSS is envisaged to serve a wider range of users, the optimal distance between these stations considering between 30 and 50 km.

 

This density is now regarded as insufficient. Network of permanent stations Cell Phone Tracker reference to US currently consists of 38 stations, the average distance between them is about. 200 km. A potential user of observations from these stations may be in the most unfavorable situation, about 100 km all GNSS reference stations standing around him. It is obvious that the holders of L1 receivers will not seek observations from these stations, with no possibility of control over the base length dependent errors. To avoid this inconvenience, technical positioning network of permanent stations sparsely been directed towards the realization of virtual reference stations.
This solution is a way to use all the information in real observations from permanent stations. The comments generated by virtual computing stations have much better characteristics compared to actual observations were carried out at these points as characteristic errors station (multipath, cycle-slip, refractions on the outskirts of obstructions) no longer exists. The functional programs that generate comments virtual stations using either linear equations to be an observation phase double difference equations. For generating virtual stations observations are necessary theoretical framework of this station, which is usually choose the center of your work area.

Data from neighboring real permanent stations are centralized on a single computer observations and worked jointly estimating ambiguities for each satellite in hand which is then extracted from the observation equations. Resulting equations containing only comments corrections, so equations reduced by satellite-receiver distance. If all observations have been reduced to a single station, the corrections obtained can be used to interpolate corrections for any other station on the network.
In the second phase, the information obtained is used to generate the virtual station accurate observations. The most difficult problem here is the modeling correct errors of observation. The modeling is done independently for each satellite in part, using flat correction, which corresponds to a two-dimensional linear interpolation. If three base stations are used the actual surrounding a virtual reference station, they form a triangle, and the area is uniquely determined by interpolation. Correction surfaces are described by two parameters that describe the interpolated surface tilt directions North and East. Modeling the influence of ionospheric refraction modeling is independent of the influence of tropospheric refraction errors and orbital so that each surface interpolation parameters are obtained in April expressed in ppm. Ionospheric refraction corrections to refer only to L1 signal.
In conditions in which all calculations are performed centrally, just a user to transmit the position of station virtual work area, being the offered remarks station virtual RINEX format, which can then be processed together with observations of real network, using a joint post-processing of satellite observations.


The great advantage of this technique lies in the fact that the short base is determined, which can be processed even for receivers with L1 frequency. This technique would be to create a solution and geodetic observations points higher order located in the woods, where they can make real observations in points in very inaccessible areas, or areas that were destroyed.

The discoveries of humanity – Electricity

The discoveries of humanity – Electricity

 

 

People live differently now more than 100 years before being discovered electricity. First they talked about electricity in history were the Greeks 2000 years ago. They noted that friction causes the amber fur attraction between the two.

In 1600, English physicist William Gilbert (May 24, 1544 – November 30, 1603) coined the term “electric”, derived from the Greek “elektron” to identify emerging force between two objects rub against each other. Gilbert used items were amber and a magnet, thus registering for the first time the word “electric” in a report about the theory of magnetism.

It is said that in 1752, Benjamin Franklin (January 17, 1706 – 17th of April 1790 the US) did a famous experiment at flying a kite tempest with silk top which sank a key iron. The experiment proved Franklin’s theory later but was very dangerous, he can be killed by lightning. This breakthrough has induced the idea that light and electricity are closely connected, later leading to the invention of the lightning rod. Benjamin Franklin’s face is placed prominently on US 100 dollar banknote.

In 1786, Luigi Galvani, an Italian professor of medicine noted that a frog leg kicking violent death when touched by a metal knife. He thought that the frog muscles are carriers of electricity.

In 1792, another scientist Alessandro Volta Italian contradicted him on Galvani’s discovery saying that the main factor is achieving the two metals: knife, metal tray that was lying frog. Volta showed that when we talk about humidity between two different metals, electricity is created. This phenomenon led him to the discovery of the first batteries, voltaic cell made of thin sheets of cupule and zinc, separated by a wet cardboard (hence the name of the unit of measure, Volt).

A great contribution to the theory of electricity had it but the Englishman Michael Faraday (Newington, September 22, 1791 – London, August 25 1867). He found that when you put a magnet in a coil of copper wire, a tiny electric current flowing through wires. It is the first method of generating electricity through movement in a magnetic field.

Sir Joseph Swan (October 31, 1828, Pallion, UK – May 27, 1924) invented the filament lamp incandescent (light) although many books and I give the inventor the popular Thomas Alva Edison (February 11, 1847 – October 18, 1931) American citizen and businessman. Edison invention registered in the US Patent Office (the only authority recognized American invention) based on a design of Swan made ten years earlier. When he learned, Swan sued him and won Edison. US Patent Office invalidated the patent to him Edison and forced him to take on Swan partner in his company. Together they managed to develop an electric lighting system that contained all the necessary elements to practical use, safe and economically incandescent light. Swan and Edison managed together to illuminate for the first time in history an electric street lamps or bulbs. It happened in September 1882 in New York.

Nikola Tesla (July 10, 1856, Smiljan Lika, Croatia – January 7, 1943, New York) is considered the “father” of today’s wireless devices. Tesla has patented engine generating AC and it seems that he sold his invention to George Westinghouse (which has and employee). At 30 he emigrated to America and was employed at the company’s Thomas Edison. There was an agreement with Edison revolt against the way in which the latter leading scientific research, has resigned and has decided to work for himself. In 1891, after the success of its system based on alternating current, Tesla transformer realized that bears his name today. This allows to obtain voltage transformer with values of up to several million volts.