Two-meter antennas are small compared to those for the lower frequency bands, and the availability of repeaters on this band greatly extends the range of lightweight low power handhelds and mobile stations. One of the most popular VHF and UHF base station antennas is the J-Pole. The J-Pole has no ground radials and it is easy to construct using inexpensive materials. For its simplicity and smal...

Large-volume metrology is essential to many high-value industries and contributes the factories of future. In this context, we have developed a tri-dimensional coordinate measurement system based on multilateration technique with self-calibration. practice, an absolute distance meter, traceable SI metre, shared between four heads by fibre-optic links. From these stations, multiple measurements ...

Trapped atomic ions have proven to be one of the most promising candidates for the realization of quantum computation due to their long trapping times, excellent coherence properties, and exquisite control of the internal atomic states. Integrating ions (quantum memory) with photons (distance link) offers a unique path to large-scale quantum computation and long-distance quantum communication. ...

Maps of pollutants concentration are usually generated by means of interpolation and extrapolation methods. The quality of the results depends mainly of the number of permanent or temporary measuring stations. This paper deals with a method for the virtual densification of the network of stations. The method creates "virtual measuring stations". It aims at improving the quality of interpolation...

The purpose of the study was to assess the incidence of alcohol and amphetamine use among long-distance truck drivers. There were studied 91 truck drivers at the gas station in Passos, Southeastern Brazil, in November 2005. Data was collected using a questionnaire comprising 19 multiple choice questions. Descriptive statistics, Chi-square test and Cramér's correlation coefficient were used for ...

The steel ball will be launched horizontally by being released at a certain height on the ramp. It will then fall to the floor and make a mark on the landing paper. The horizontal distance from take-off to landing, x, is proportional to the initial horizontal velocity, v0, of the ball. The distance, x, can be measured with the meter stick. By using the SALT®, photogate and computer, the time ca...

BACKGROUND In the early stages of Pandemic (H1N1) 2009, border control measures were taken by quarantine stations to block the entry of infected individuals into Japan and community containment measures were implemented to prevent the spreading. The objectives of this study were to describe these measures and the characteristics of infected individuals, and to assess the measures' effectiveness...

Given a finite set S of points (i.e. the stations of a radio network) on the plane and a positive integer 1 ≤ h ≤ |S| − 1, the 2d Min h R. Assign. problem consists of assigning transmission ranges to the stations so as to minimize the total power consumption provided that the transmission ranges of the stations ensure the communication between any pair of stations in at most h hops. We provide ...

rainfall spatial analysis methods are very helpful since there are not enough rainfall gauge stations and watersheds are scattered in large extent. there are many different methods for estimating average precipitation such as; arithmetic method and thiessen polygon. however, the arrangement and location of data and their correlations are not considered by classic methods. thus, geostatistical t...