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Transmissibility (other)
Transmissibility may have several meanings: * Transmissibility (vibration) * Transmissibility (electromagnetism) * Transmissivity, fluid flow in porous media * Transmissibility (structural dynamics) In most contexts, transmissibility is related to permeability. In medicine, transmissibility is a synonym for basic reproduction number and refers to transmission. See also * Transmitter, a device for propagating electronic signals * Transmittance Transmittance of the surface of a material is its effectiveness in transmitting radiant energy. It is the fraction of incident electromagnetic power that is transmitted through a sample, in contrast to the transmission coefficient, which is th ..., in optics, the propagation of a light wave through a medium * Transmissivity in hydraulics {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmissibility (vibration)
Transmissibility is the ratio of output to input. It is defined as the ratio of the force transmitted to the force applied. Transmitted force implies the one which is being transmitted to the foundation or to the body of a particular system. Applied force is the external agent that cause the force to be generated in the first place and be transmitted. Transmissibility: T = \frac T>1 means amplification and maximum amplification occurs when forcing frequency (f_f) and natural frequency (f_n) of the system coincide. There is no unit designation for transmissibility, although it may sometimes be referred to as the ''Q factor''. The transmissibility is used in calculation of passive hon efficiency. The lesser the transmissibility the better is the damping or the isolation system. T1 is Undesirable See also * Q factor In physics and engineering, the quality factor or ''Q'' factor is a dimensionless parameter that describes how underdamped an oscillator or resonator is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmissibility (electromagnetism)
The Fresnel equations (or Fresnel coefficients) describe the reflection and transmission of light (or electromagnetic radiation in general) when incident on an interface between different optical media. They were deduced by Augustin-Jean Fresnel () who was the first to understand that light is a transverse wave, even though no one realized that the "vibrations" of the wave were electric and magnetic fields. For the first time, polarization could be understood quantitatively, as Fresnel's equations correctly predicted the differing behaviour of waves of the ''s'' and ''p'' polarizations incident upon a material interface. Overview When light strikes the interface between a medium with refractive index ''n''1 and a second medium with refractive index ''n''2, both reflection and refraction of the light may occur. The Fresnel equations give the ratio of the ''reflected'' wave's electric field to the incident wave's electric field, and the ratio of the ''transmitted'' wave's electri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Conductivity
Hydraulic conductivity, symbolically represented as (unit: m/s), is a property of porous materials, soils and rocks, that describes the ease with which a fluid (usually water) can move through the pore space, or fractures network. It depends on the intrinsic permeability (, unit: m) of the material, the degree of saturation, and on the density and viscosity of the fluid. Saturated hydraulic conductivity, , describes water movement through saturated media. By definition, hydraulic conductivity is the ratio of volume flux to hydraulic gradient yielding a quantitative measure of a saturated soil's ability to transmit water when subjected to a hydraulic gradient. Methods of determination There are two broad categories of determining hydraulic conductivity: *''Empirical'' approach by which the hydraulic conductivity is correlated to soil properties like pore size and particle size (grain size) distributions, and soil texture *''Experimental'' approach by which the hydraulic conducti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmissibility (structural Dynamics)
Transmissibility, in the context of Structural Dynamics, can be defined as the ratio of the maximum force (f_) on the floor as a result of the vibration of a machine to the maximum machine force (P_0): :TR = \frac = R_d\sqrt{1+(2\zeta\beta)^2} :Where \zeta is equal to the damping ratio Damping is an influence within or upon an oscillatory system that has the effect of reducing or preventing its oscillation. In physical systems, damping is produced by processes that dissipate the energy stored in the oscillation. Examples inc ... and \beta is equal to the frequency ratio. R_d is the ratio of the dynamic to static amplitude. Further reading Vibration Control and MeasurementTech Tip: Spring & Dampers, Episode Four Structural analysis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permeability (other)
Permeability, permeable, and semipermeable may refer to: Chemistry *Semipermeable membrane, a membrane which will allow certain molecules or ions to pass through it by diffusion *Vascular permeability, the movement of fluids and molecules between the vascular and extravascular compartments *Permeation of a gas or vapor through a solid substance Earth and soil science * Permeability (earth sciences), a measure of the ability of a material (such as rocks) to transmit fluids **Relative permeability, in multiphase flow in porous media *Permeability (foundry sand), a test of the venting characteristics of a rammed foundry sand *Hydraulic conductivity, the permeability of soil for water Electromagnetism *Permeability (electromagnetism), the degree of magnetization of a material in response to a magnetic field **Vacuum permeability, permeability of free space or magnetic constant, a physical constant, the value of magnetic permeability in a classical vacuum Vehicles and transport ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basic Reproduction Number
In epidemiology, the basic reproduction number, or basic reproductive number (sometimes called basic reproduction ratio or basic reproductive rate), denoted R_0 (pronounced ''R nought'' or ''R zero''), of an infection is the expected number of cases directly generated by one case in a population where all individuals are susceptible to infection. The definition assumes that no other individuals are infected or immunized (naturally or through vaccination). Some definitions, such as that of the Australian Department of Health, add the absence of "any deliberate intervention in disease transmission". The basic reproduction number is not necessarily the same as the effective reproduction number R (usually written R_t 't'' for time sometimes R_e), which is the number of cases generated in the current state of a population, which does not have to be the uninfected state. R_0 is a dimensionless number (persons infected per person infecting) and not a time rate, which would have units ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission (medicine)
In medicine, public health, and biology, transmission is the passing of a pathogen causing communicable disease from an infected host individual or group to a particular individual or group, regardless of whether the other individual was previously infected. The term strictly refers to the transmission of microorganisms directly from one individual to another by one or more of the following means: * airborne transmission – very small dry and wet particles that stay in the air for long periods of time allowing airborne contamination even after the departure of the host. Particle size 5 μm. * direct physical contact – touching an infected individual, including sexual contact * indirect physical contact – usually by touching a contaminated surface, including soil (fomite) * fecal–oral transmission – usually from unwashed hands, contaminated food or water sources due to lack of sanitation and hygiene, an important transmission route in pediatrics, veterinary medicine and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmitter
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna (radio), antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the Antenna (radio), antenna. When excited by this alternating current, the antenna radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio communication, radio, such as radio broadcasting, radio and television broadcasting stations, cell phones, walkie-talkies, Wireless LAN, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term ''transmitter'' is usually limited to equipment that generates radio waves for Communication engineering, communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio waves for heatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmittance
Transmittance of the surface of a material is its effectiveness in transmitting radiant energy. It is the fraction of incident electromagnetic power that is transmitted through a sample, in contrast to the transmission coefficient, which is the ratio of the transmitted to incident electric field. Internal transmittance refers to energy loss by absorption, whereas (total) transmittance is that due to absorption, scattering, reflection, etc. Mathematical definitions Hemispherical transmittance Hemispherical transmittance of a surface, denoted ''T'', is defined as :T = \frac, where *Φet is the radiant flux ''transmitted'' by that surface; *Φei is the radiant flux received by that surface. Spectral hemispherical transmittance Spectral hemispherical transmittance in frequency and spectral hemispherical transmittance in wavelength of a surface, denoted ''T''ν and ''T''λ respectively, are defined as :T_\nu = \frac, :T_\lambda = \frac, where *Φe,νt is the spectral radiant flux ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
