|
Cavity
Cavity may refer to: Biology and healthcare *Body cavity, a fluid-filled space in many animals where organs typically develop **Gastrovascular cavity, the primary organ of digestion and circulation in cnidarians and flatworms *Dental cavity or tooth decay, damage to the structure of a tooth *Lung cavity, an air-filled space within the lung Radio frequency resonance * Microwave cavity or ''RF cavity'', a cavity resonator in the radio frequency range, for example used in particle accelerators * Optical cavity, the cavity resonator of a laser * Resonant cavity, a device designed to select for waves of particular wavelengths Other uses *Cavity (band), a sludge metal band from Miami, Florida *Cavity method, a mathematical method to solve some mean field type of models *Cavity wall, a wall consisting of two skins with a cavity See also * Cavitation, the phenomenon of partial vacuums forming in fluid, for example, in propellers * Cavitary pneumonia, a type of pneumonia in which a ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavity Wall
A cavity wall is a type of wall that has a hollow center. They can be described as consisting of two "skins" separated by a hollow space (cavity). The skins typically are masonry, such as brick or cinder block. Masonry is an absorbent material that can slowly draw rainwater or even humidity into the wall. One function of the cavity is to drain water through weep holes at the base of the wall system or above windows. The weep holes allow wind to create an air stream through the cavity that exports evaporated water from the cavity to the outside. Usually, weep holes are created by separating several vertical joints approximately two meters apart at the base of each story. Weep holes are also placed above windows to prevent dry rot of wooden window frames. A cavity wall with masonry as both inner and outer skins is more commonly referred to as a double wythe masonry wall. History Cavity wall construction was introduced in the United Kingdom during the 19th century and gained w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavity (band)
Cavity is an American sludge metal band from Miami, Florida. They first formed in 1992, releasing a multitude of albums and singles before breaking up in 2003. Steve Brooks and Juan Montoya would go on to play in Torche and Floor. Anthony Vialon, Henry Wilson and Beatriz Monteavaro also played in Floor. Jason Landrian went on to form Black Cobra. In 2015, the group reunited and toured the United States for the first time since their dissolution. The group issued their first album since their reunion, titled ''After Death'', through Valley King in 2017. Discography Studio albums * ''Human Abjection'' (1995, City of Crime) * ''Somewhere Between the Train Station and the Dumping Grounds'' (1997, Rhetoric) * ''SuperCollider'' (1999, Man's Ruin) * ''On the Lam'' (2001, Hydra Head) * ''After Death'' (2017, Valley King) *''Wraith'' (2019, Valley King) Singles and EPs * ''Cavity'' demo tape (1992, self-released) * ''Scalpel'' 7-inch (1996, City of Crime) * ''Crawling'' 7-inch (1996, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resonant Cavity
A resonator is a device or system that exhibits resonance or resonant behavior. That is, it naturally oscillates with greater amplitude at some frequencies, called resonant frequencies, than at other frequencies. The oscillations in a resonator can be either electromagnetic or mechanical (including acoustic). Resonators are used to either generate waves of specific frequencies or to select specific frequencies from a signal. Musical instruments use acoustic resonators that produce sound waves of specific tones. Another example is quartz crystals used in electronic devices such as radio transmitters and quartz watches to produce oscillations of very precise frequency. A cavity resonator is one in which waves exist in a hollow space inside the device. In electronics and radio, microwave cavities consisting of hollow metal boxes are used in microwave transmitters, receivers and test equipment to control frequency, in place of the tuned circuits which are used at lower f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Cavity
Tooth decay, also known as cavities or caries, is the breakdown of teeth due to acids produced by bacteria. The cavities may be a number of different colors from yellow to black. Symptoms may include pain and difficulty with eating. Complications may include inflammation of the tissue around the tooth, tooth loss and infection or abscess formation. The cause of cavities is acid from bacteria dissolving the hard tissues of the teeth ( enamel, dentin and cementum). The acid is produced by the bacteria when they break down food debris or sugar on the tooth surface. Simple sugars in food are these bacteria's primary energy source and thus a diet high in simple sugar is a risk factor. If mineral breakdown is greater than build up from sources such as saliva, caries results. Risk factors include conditions that result in less saliva such as: diabetes mellitus, Sjögren syndrome and some medications. Medications that decrease saliva production include antihistamines and antidepress ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavity Search (other)
A body cavity search, also known simply as a cavity search, is either a visual search or a manual internal inspection of body cavities for prohibited materials ( contraband), such as illegal drugs, money, jewelry, or weapons. Body cavities frequently used for concealment include the mouth, vagina, and rectum. It is far more invasive than the standard strip search that is typically performed on individuals taken into custody, either upon police arrest or incarceration at a jail, prison, or psychiatric hospital. Often the procedure is repeated when the person leaves the institution. Body cavity searches may also be conducted at some international border crossings such as the U.S. Customs and Border Protection when they suspect international travelers of hiding contraband—such as drugs Procedure Many articles of contraband are concealable in the body's cavities, via means such as insertion into the rectum. Illegal drugs are often found in condoms and temporarily stowed in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrovascular Cavity
The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Coelenterates or cnidarians (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a "blind gut" or "blind sac", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea between. Extracellular digestion takes place within the central cavity of the sac-like body. This cavity has only one opening to the outside which, in most cnidarians, is surrounded by tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Cavity
A microwave cavity or ''radio frequency (RF) cavity'' is a special type of resonator, consisting of a closed (or largely closed) metal structure that confines electromagnetic fields in the microwave region of the spectrum. The structure is either hollow or filled with dielectric material. The microwaves bounce back and forth between the walls of the cavity. At the cavity's resonant frequencies they reinforce to form standing waves in the cavity. Therefore, the cavity functions similarly to an organ pipe or sound box in a musical instrument, oscillating preferentially at a series of frequencies, its resonant frequencies. Thus it can act as a bandpass filter, allowing microwaves of a particular frequency to pass while blocking microwaves at nearby frequencies. A microwave cavity acts similarly to a resonant circuit with extremely low loss at its frequency of operation, resulting in quality factors (Q factors) up to the order of 106, compared to 102 for circuits made with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Cavity
An optical cavity, resonating cavity or optical resonator is an arrangement of mirrors or other optical elements that forms a cavity resonator for light waves. Optical cavities are a major component of lasers, surrounding the gain medium and providing feedback of the laser light. They are also used in optical parametric oscillators and some interferometers. Light confined in the cavity reflects multiple times, producing modes with certain resonance frequencies. Modes can be decomposed into longitudinal modes that differ only in frequency and transverse modes that have different intensity patterns across the cross-section of the beam. Many types of optical cavity produce standing wave modes. Different resonator types are distinguished by the focal lengths of the two mirrors and the distance between them. Flat mirrors are not often used because of the difficulty of aligning them to the needed precision. The geometry (resonator type) must be chosen so that the beam remains st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavity Method
The cavity method is a mathematical method presented by Marc Mézard, Giorgio Parisi and Miguel Angel Virasoro in 1987 to solve some mean field type models in statistical physics, specially adapted to disordered systems. The method has been used to compute properties of ground states in many condensed matter and optimization problems. Initially invented to deal with the Sherrington–Kirkpatrick model of spin glasses, the cavity method has shown wider applicability. It can be regarded as a generalization of the Bethe— Peierls iterative method in tree-like graphs, to the case of a graph with loops that are not too short. The different approximations that can be done with the cavity method are usually named after their equivalent with the different steps of the replica method which is mathematically more subtle and less intuitive than the cavity approach. The cavity method has proved useful in the solution of optimization problems such as k-satisfiability and graph coloring. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Cavity
A body cavity is any space or compartment, or potential space, in an animal body. Cavities accommodate organs and other structures; cavities as potential spaces contain fluid. The two largest human body cavities are the ventral body cavity, and the dorsal body cavity. In the dorsal body cavity the brain and spinal cord are located. The membranes that surround the central nervous system organs (the brain and the spinal cord, in the cranial and spinal cavities) are the three meninges. The differently lined spaces contain different types of fluid. In the meninges for example the fluid is cerebrospinal fluid; in the abdominal cavity the fluid contained in the peritoneum is a serous fluid. In amniotes and some invertebrates the peritoneum lines their largest body cavity called the coelom. Mammals Mammalian embryos develop two body cavities: the intraembryonic coelom and the extraembryonic coelom (or chorionic cavity). The intraembryonic coelom is lined by somatic and sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lung Cavity
A lung cavity or pulmonary cavity is an abnormal, thick-walled, air-filled space within the lung. Cavities in the lung can be caused by infections, cancer, autoimmune conditions, trauma, congenital defects, or pulmonary embolism. The most common cause of a single lung cavity is lung cancer. Bacterial, mycobacterial, and fungal infections are common causes of lung cavities. Globally, tuberculosis is likely the most common infectious cause of lung cavities. Less commonly, parasitic infections can cause cavities. Viral infections almost never cause cavities. The terms ''cavity'' and ''cyst'' are frequently used interchangeably; however, a ''cavity'' is thick walled (at least 5 mm), while a ''cyst'' is thin walled (4 mm or less). The distinction is important because cystic lesions are unlikely to be cancer, while cavitary lesions are often caused by cancer. Diagnosis of a lung cavity is made with a chest X-ray or CT scan of the chest, which helps to exclude mimics like lung cysts, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavitation
Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, called "bubbles" or "voids", collapse and can generate shock waves that may damage machinery. These shock waves are strong when they are very close to the imploded bubble, but rapidly weaken as they propagate away from the implosion. Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic stress through repeated implosion. This results in surface fatigue of the metal causing a type of wear also called "cavitation". The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
