Propulsion

Propulsion is a means of creating force leading to movement. The term is derived from two Latin words: pro, meaning after or forward; and pellere, meaning to drive. A propulsion system consists of a source of mechanical power, and a propulsor (means of converting this power into propulsive force).

A technological system uses an engine or motor as the power source, and wheels and axles, propellers, or a propulsive nozzle to generate the force. Components such as clutches or gearboxes may be needed to connect the motor to axles, wheels, or propellors.

Biological propulsion systems use an animal's muscles as the power source, and limbs such as wings, fins or legs as the propulsors.

Vehicular propulsion

Air propulsion

An aircraft propulsion system generally consists of an aircraft engine and some means to generate thrust, such as a propeller or a propulsive nozzle.

An aircraft propulsion system must achieve two things. First, the thrust from the propulsion system must balance the drag of the airplane when the airplane is cruising. And second, the thrust from the propulsion system must exceed the drag of the airplane for the airplane to accelerate. In fact, the greater the difference between the thrust and the drag, called the excess thrust, the faster the airplane will accelerate.

Wave

In physics, a wave is an oscillation accompanied by a transfer of energy that travels through space or mass. Frequency refers to the addition of time. Wave motion transfers energy from one point to another, which displace particles of the transmission medium—that is, with little or no associated mass transport. Waves consist, instead, of oscillations or vibrations (of a physical quantity), around almost fixed locations.

There are two main types of waves. Mechanical waves propagate through a medium, and the substance of this medium is deformed. The deformation reverses itself owing to restoring forces resulting from its deformation. For example, sound waves propagate via air molecules colliding with their neighbors. When air molecules collide, they also bounce away from each other (a restoring force). This keeps the molecules from continuing to travel in the direction of the wave.

The second main type of wave, electromagnetic waves, do not require a medium. Instead, they consist of periodic oscillations of electrical and magnetic fields originally generated by charged particles, and can therefore travel through a vacuum. These types of waves vary in wavelength, and include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

Wave (magazine)

WAVE is an English-language, monthly magazine published by Annapurna Media Pvt. Ltd. Each month, the magazine publishes articles addressing the youth and their varied interests. Apart from touching on the lighter fun side, it also addresses more "serious" aspects - but from a youthful perspective. The magazine has a large impact on the urban Nepali youth.

WAVE magazine is based in Kupondole, Lalitpur.

External links

Park West, Dublin

Park West (Irish: Páirc an Iarthair) is a large business campus within greater Ballyfermot, notably Cherry Orchard, Dublin, Ireland, with some residential development.

There are over 300 companies with 10,000 employees.

Location and content

Located just inside the M50 orbital motorway in west Dublin, the development comprises several million square metres of office and retail space, along with an Aspect hotel, a private hospital, and three apartment complexes.

Park West is in the administration of Dublin City Council, and Dublin postal districts Dublin 10 and Dublin 12, chiefly the latter.

Art

Park West is home to Europe's tallest wind and water mobile sculpture, Wave by Angela Conner. It is a 39.3 metre (129 feet) tall sculpture made of polystyrene covered with layers of carbon resin. It is fixed into a 7.6 metre (25 foot) pit filed with 9.5 tonnes of lead.

Transport

The campus is accessible by road (primarily the (New) Nangor Road, as well as Killeen Road and Cloverhill), bus (routes 79A and 151) and rail at the Park West and Cherry Orchard railway station. At a moderate distance to the south is the Kylemore stop on the Luas red line.