Hourglass (meaning, definition)

An hourglass is a glass with 2 bulbs on the end and a narrowing in the middle where the sand needs to go through. The package of sand that needs to go through the narrowing is mostly equal to 1 hour if all the sand has be flown into one bulb.

Cabret (meaning, Definition)

Goat leather for gloves.

Facsimile (meaning, definition)

A facsimile is an exact imitation of writings, printed matter, prints and drawings.

Tramp (meaning, definition)

A tramp is an old glas object to measure the time. Sometimes it's called an hourglass.

Axe (ax) (definition and significance)

An axe is a hatchet with a long handle, sometimes called an ax without an e.

In the Middle Ages it was extensively used by lumberjacks to cut down trees. When there was war the axemen used their axes as a weapons.

Nuclear Fusion, the eternal promise as renewable energy?

Fusion is the energy of the sun and the stars, and the largest source of energy in the universe. The ITER fusion reactor that has to rise in Cadarache, France, costs billions of euro's to be paid by a number of countries including Japan and the USA. China is already building its own nuclear fusion reactor. It's a battle between lobbyists for power, money and new techniques because all of the great powers want to protect their energy sources. Will the nuclear fusion the energy source of the future? We will know perhaps until 2050.
See on Wikipedia a larger definition of Nuclear Fusion and how it works.

Nuclear Power Plant

Aneroid barometer, meaning (English)

What is an aneroid barometer? - Definition
An aneroid barometer is a metal barometer, with an almost airless box with air pressure. It measures the pressure differences of air. The degree of structure of the box by the surrounding air is possible by using a needle on a distribution. The Barometer works on the principle of series-switched aneroid (vacuum) boxes or capsules (known as jewel case inserts of Vidi). These cases are usually made of phosphor-bronze or beryllium-copper. If air pressure rise than the boxes are more pressed in, the boxes are less pressed by low air pressure. Through a lever system, these changes were transferred to a needle that moves over a scale. Most home barometers are aneroid barometers. In Surveying (barometric elevation) make this system of sophisticated barometers (aneroid Paulin) service to the elevation of different points to be determined. A barometer usually contains mercury, the aneroid barometer contains no mercury. The aneroid barometer is only used for weather forecasts to measure and record.

Other sorts of Aneroid barometers:

Aneroid barometer of Fues
An aneroid barometer with analog indicator, whose sensing element consists of a number of linked, on top of each confirmed vacuum flat boxes (box Vidi) of beryllium. The change in air pressure can be specified by a lever system and is specified by a pointer. The scale ranges from 920-108 (hPa) and is divided into units of 1 hectoPascal (this unit corresponds to the millibar (mbar).

Negretti and Zambra aneroid barometer
Precision aneroid barometer with digital display. This instrument consists of a set of Vidi boxes. The difference with the aneroid barometer Fuess is that the deformation of the Vidi boxes in this case through a complex mechanism delay is enlarged on a scale. Using a stylus the compression of the Vidi-boxes is directed via a pin and a lever transferred to a graduated scale. This barometer responds so smoothly and is also less susceptible to inaccuracies that may occur upon the expiration of the instrument.

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Anemometer - meaning (English)

What is an anemometer (short definition)
An Anemometer is an instrument with which the wind can be determined.

Windmill with hemispheres
This instrument was introduced in 1846 by the Irish astronomer Thomas Romney Robinson (1792-1882). This instrument is a rotating windmill with three or four hemispheres (cups) with a rotating shaft rods to be confirmed. The axis is approximately perpendicular to the direction of the wind measurement. The hemispheres are hollow inside. If there are only three hemispheres then they are present prepared at 120° apart. The windmill will rotate because the wind on the concave side exerts more than on the convex side. The motion of the rotating balls through the ashes transform into a dynamo with an electrical voltage signal. The rotation speed of the wind speed are derived. This wind speed is expressed in meters per second or kilometers per hour.

Paddle wheel
Another form of an anemometer is used to measure the speed of the air (mine shafts, air conditioning) in buildings. With this type of windmill has blades in the wing shape or consists of a wheel with blades. The shaft is parallel to the direction of the wind. The weather puts a dynamo coupled motion into electrical voltage.

Ultrasonic anemometer
These motionless sensor is based on the principle that the propagation speed of sound changes with the wind speed. The direction of the wind can be lead and peaks can be measured.

Thermal anemometers
This consists of two heated Pt100 measuring sensors, which are kept constantly in temperature differences. By passing air, the sensors can cooling off. The electric power which is necessary in order to maintain the temperature difference is measured and is a measure of the airspeed.
This type is similar to the classic hot wire anemometer, where the cooling is a measurement of the flow rate of the wind. The cooling effect, for example, a temperature sensitive resistance (NTC) in an electronic circuit, ensures that the wind speed is converted into a voltage or power difference.

Laser Doppler anemometer
Light scattering by particles in the flowing air can also be used as a measure of wind speed. Returning light has twice undergone a Doppler effect, from which speed can be found.

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