Sound

In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure and displacement, through a medium such as air or water. In physiology and psychology, sound is the reception of such waves and their perception by the brain.

Acoustics

Acoustics is the interdisciplinary science that deals with the study of mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound, and infrasound. A scientist who works in the field of acoustics is an acoustician, while someone working in the field of acoustical engineering may be called an acoustical engineer. An audio engineer, on the other hand is concerned with the recording, manipulation, mixing, and reproduction of sound.

Applications of acoustics are found in almost all aspects of modern society, subdisciplines include aeroacoustics, audio signal processing, architectural acoustics, bioacoustics, electro-acoustics, environmental noise, musical acoustics, noise control, psychoacoustics, speech, ultrasound, underwater acoustics, and vibration.

Urethral sounding

Sounding or urethral sounding is the medical use of probes called sounds to increase the inner diameter of the urethra and to locate obstructions in it. Sounds are also used to stretch the urethra in order to receive genital piercing.

Urethral sounding and urethral play are also used to refer to this practice in a sexual context.

Urethral play can involve the introduction of either soft or rigid items into the meatus of the penis (as well as farther in). Objects such as sounds are usually only inserted about halfway into the glans and can usually be easily retrieved. Other toys and items, such as catheters, may be introduced deeper; in some cases even into the bladder. Some items may even be allowed to curl several times or expand within the bladder. This action in the male may be directly or indirectly associated with stimulation of the prostate gland and some types of bladder control.

Risks

If not conducted carefully, sounding carries a risk of irritation, tearing of the urethra, or of urinary tract infection. Infections may become serious if they progress to the bladder or kidneys, and should be referred to a doctor.

Sound (nautical)

In nautical terms, the word sound is used to describe the process of determining the depth of water in a tank or under a ship. Tanks are sounded to determine if they are full (for cargo tanks) or empty (to determine if a ship has been holed) and for other reasons. Soundings may also be taken of the water around a ship if it is in shallow water to aid in navigation.

Methods

Tanks may be sounded manually or with electronic or mechanical automated equipment. Manual sounding is undertaken with a sounding line- a rope with a weight on the end. Per the Code of Federal Regulations, most steel vessels with integral tanks are required to have sounding tubes and reinforcing plates under the tubes which the weight strikes when it reaches the bottom of the tank. Sounding tubes are steel pipes which lead upwards from the ships' tanks to a place on deck.

Electronic and mechanical automated sounding may be undertaken with a variety of equipment including float level sensors, capacitance sensors, sonar, etc.

PCP

PCP may refer to:

Computing

Medicine and pharmaceutics

Politics

Probabilistically checkable proof

In computational complexity theory, a probabilistically checkable proof (PCP) is a type of proof that can be checked by a randomized algorithm using a bounded amount of randomness and reading a bounded number of bits of the proof. The algorithm is then required to accept correct proofs and reject incorrect proofs with very high probability. A standard proof (or certificate), as used in the verifier-based definition of the complexity class NP, also satisfies these requirements, since the checking procedure deterministically reads the whole proof, always accepts correct proofs and rejects incorrect proofs. However, what makes them interesting is the existence of probabilistically checkable proofs that can be checked by reading only a few bits of the proof using randomness in an essential way.

Probabilistically checkable proofs give rise to many complexity classes depending on the number of queries required and the amount of randomness used. The class PCP[r(n),q(n)] refers to the set of decision problems that have probabilistically checkable proofs that can be verified in polynomial time using at most r(n) random bits and by reading at most q(n) bits of the proof. Unless specified otherwise, correct proofs should always be accepted, and incorrect proofs should be rejected with probability greater than 1/2. The PCP theorem, a major result in computational complexity theory, states that PCP[O(log n),O(1)] = NP.

Peruvian Communist Party

The Peruvian Communist Party (in Spanish: Partido Comunista Peruano) is a communist party in Peru. It was founded in 1928 by José Carlos Mariátegui, under the name Partido Socialista del Perú (Socialist Party of Peru). In 1930 the name was changed to PCP. PCP is often identified as PCP [Unidad], to separate it from the Communist Party of Peru.

Jorge Del Prado was the general secretary between 1966 and 1991. In 1980 the PCP and other left-wing groups formed the United Left.

The main political base of the PCP is currently located at Plaza Ramón Castilla, Lima and is led by Roberto De La Cruz Huama. PCP publishes Unidad (Unity) and Nuestra Bandera (Our Flag).

In the 2011 general election the party took part in the successful Peru Wins alliance of Ollanta Humala.

See also

External links