hemisphere to give the hemispherical spectral reflectivity math rho lambda frac G mathrm refl ... to give the total hemispherical reflectivity , or reflectance factor math rho frac G mathrm refl G mathrm incid math Reflectance Reflectivity and reflectance generally refer to the fraction of incident ... of Optics ref The reflectance or reflectivity is thus the square of the magnitude of the reflection ... layer, whereas the reflectance or reflectivity is always a positive real number . According ... the International Commission on Illumination ref reflectivity is distinguished from reflectance by the fact that reflectivity is a value that applies to thick reflecting objects. ref name ILV http www.cie.co.at ... with surface thickness. Reflectivity is the limit value of reflectance as the surface becomes thick ... of electromagnetic power reflected from a specific sample, while reflectivity is a property of the material .... Surface type Going back to the fact that reflectivity is a directional property, most surfaces ... . For specular surfaces, such as glass or polished metal, reflectivity will be nearly zero at all ... surfaces, such as matte white paint, reflectivity is uniform radiation is reflected in all angles ... objects have some mixture of diffuse and specular reflective properties. Water reflectivity Image Water reflectivity.jpg thumb right 400px Reflectivity of smooth water at 20 C refractive index 1.333 Reflection ... significantly to albedo which is primarily diffuse reflection. A real water surface may be wavy. Reflectivity ... light by wavelength , is called diffraction efficiency . Applications Reflectivity is an important ... of Atmospheric and Oceanic Technology, 25 5 , 715 728. ref Reflist External links Wiktionary reflectivity ... more details
Reflectivity range is the term used in X ray reflectometry and several other radar related or emission related sciences to describe the range at which reflected emissions become indecipherable due to the reflection angle and or range. Category Optics Category X rays Category Radar Tech stub ... more details
X ray reflectivity sometimes known as X ray specular reflectivity , X ray reflectometry , or XRR , is a surface sensitive analytical technique used in chemistry , physics , and materials science to characterize surfaces, thin films and multilayers. ref Holy, V. et al. Phys. Rev. B. 47 , 15896 1993 . ref ref Jens Als Nielsen, Elements of Modern X Ray Physics , Wiley, New York, 2001 . ref ref J.Daillant, A.Gibaud, X Ray and Neutron Reflectivity Principles and Applications . Springer, 1999 . ref ref M.Tolan, X Ray Scattering from Soft Matter Thin Films , Springer, 1999 ref It is related to the complementary techniques of neutron reflectometry and ellipsometry . The basic idea behind the technique is to reflect a beam of x ray s from a flat surface and to then measure the intensity of x rays reflected in the specular direction reflected angle equal to incident angle . If the interface is not perfectly sharp and smooth then the reflected intensity will deviate from that predicted by the law of Fresnel reflectivity . The deviations can then be analyzed to obtain the density profile of the interface normal to the surface. The technique appears to have first been applied to x rays by Professor Lyman G. Parratt of Cornell University in an article published in Physical Review in 1954. ref L. G. Parratt, Phys. Rev. 95 , 359 1954 . ref Parratt s initial work explored the surface of copper coated glass, but since that time the technique has been extended to a wide range of both solid and liquid interfaces. The basic mathematical relationship which describes specular reflectivity is fairly ... given by math rho e z math , then the x ray reflectivity can be approximated by ref J. Als Nielsen ... math is the reflectivity, math Q 4 pi sin theta lambda math , math lambda math is the x ray wavelength ... profile in the z direction with the measured x ray reflectivity and then vary the parameters until ... reflection For films with multiple layers, X ray reflectivity may show oscillations with wavelength ... more details
Cloud reflectivity enhancement is also known as marine cloud brightening or cloud whitening on low cloud. An opposite scheme exists to reduce the reflectivity of higher, colder cirrus clouds . ref name ReferenceA cite doi 10.1088 1748 9326 4 4 045102 ref It is a geoengineering technique that works by solar radiation management . By modifying the reflectivity of clouds, the albedo of the Earth is altered. The intention is that this technique, in combination with greenhouse gas emissions reduction and possibly other geoengineering techniques will be sufficient to control global warming . Compared to other climate modification strategies, this technique is relatively simple and benign, being based as it is on natural processes of ocean spray . It can therefore be deployed quickly for further research, and can then be rolled out on an effective scale relatively cheaply after that. The effect is expected to be fully reversible, as the cloud condensation nuclei particles precipitate naturally. However, like any planetary scale project dealing with the complex climate system, there is a non trivial risk of unintended consequences . Basic principles Low level stratocumulus clouds cover approximately one third of the oceans surface. These clouds possess Albedo levels of 0.3 0.7. ref Schwartz and Slingo, 1996 S.E. Schwartz and A. Slingo In P. Crutzen, Editor, Clouds, Chemistry and Climate Proceedings of NATO Advanced Research Workshop 1996 . ref The levels of albedo present in the low level marine stratocumulus clouds create a significant global cooling effect. ref Latham, 2002 J. Latham ... level clouds to enhance their reflectivity. The power for the rotors and the ship is generated ... portion with iron in order to enhance dimethyl sulfide production and cloud reflectivity . ref cite .... Instead of increasing the incoming shortwave reflectivity and lifetime of the cloud in order to increase the net radiative cooling effect, the outgoing infrared reflectivity and lifetime are reduced ... more details
Gleam may refer to reflectivity Gleam album The Gleam Gay and Lesbian Employees at Microsoft GLEAM Samsung SCH u700 , also called the Samsung Gleam disambig ... more details
Aluminized cloth is a material designed to reflect thermal radiation. Applications include fire proximity suits, emergency space blankets, and insulation for building and containers. See also Fire proximity suit Reflectivity Space blanket Thermal insulation Category Technical materials Category Safety clothing material stub ... more details
DBZ stands for dBZ meteorology , decibels of Z, a meteorological measure of equivalent reflectivity Z of a radar signal Dragon Ball Z , the anime adaptation of the second portion of the Dragon Ball manga Divided by Zero , an American rock band Dean Zelinsky born 1957 , American guitar designer and founder of DBZ Guitars disambig de DBZ fr DBZ it DBZ nl DBZ sv DBZ ... more details
Some Measuring instrument scientific instrument s commonly designated Reflectometer are Network analyzer electrical Vector Network Analyser VNA Spectrophotometer in optics , an instrument for measuring the reflectivity or reflectance of reflecting surfaces Optical time domain reflectometer Reflectometer electronics In electronics , a directional coupler containing matched calibrated detectors in both arms of the auxiliary line, or a pair of single detector couplers oriented so as to measure the electrical power flowing in both directions in the main line Time domain reflectometer disambig ru ... more details
General Geoengineering List of proposed geoengineering projects Solar radiation management Solar radiation management Stratospheric sulfur aerosols geoengineering Space sunshade Cloud reflectivity enhancement Stratospheric Particle Injection for Climate Engineering Greenhouse gas remediation Greenhouse gas remediation Biochar Bio energy with carbon capture and storage Carbon sequestration Iron fertilisation Ocean nourishment Enhanced weathering Other projects Arctic geoengineering Category Geoengineering Category Climatology Category Climate change related lists geoengineering Category Outlines ... more details
in a DBR increases the mirror reflectivity and increasing the refractive index contrast between the materials in the Bragg pairs increases both the reflectivity and the bandwidth. A common choice ... resonator or optical cavity in fiber laser s and free electron laser s. TE and TM mode reflectivity Image DBR TE MODE.PNG thumb left Calculated reflectivity for TE mode light at various incidence ... colors 0 R 1. Image DBR TM MODE.PNG thumb right Calculated reflectivity for TM mode light at various ..., over several wavelengths and incidence angles. This reflectivity of the DBR structure described ... more details
In optics , a Gires Tournois etalon is a transparent plate with two reflecting surfaces, one of which has very high reflectivity. Due to multiple beam interference , light incident on the lower reflectivity surface of a Gires Tournois etalon is almost completely reflected, but has a phase shift that depends strongly on the wavelength of the light. The complex amplitude reflectivity of a Gires Tournois etalon is given by math r frac r 1 e i delta 1 r 1 e i delta math where r sub 1 sub is the complex amplitude reflectivity of the first surface, br math delta frac 4 pi lambda n t cos theta t math n is the index of refraction of the plate t is the thickness of the plate &theta sub t sub is the angle of refraction the light makes within the plate, and &lambda is the wavelength of the light in vacuum. Nonlinear phase shift Image Phase Shift.gif thumb right 400px Nonlinear phase shift &Phi as a function of &delta for different R values a R 0, b R 0.1, c R 0.5, and d R 0.9. Note that math r 1 math , independent of math delta math . This indicates that all the incident energy is reflected and intensity is uniform. However, the multiple reflection causes a nonlinear phase shift math Phi math . To show this effect, we assume math r 1 math is real and math r 1 sqrt R math , where math R math is the intensity reflectivity of the first surface. Further, define the nonlinear phase shift math Phi math through math r e i Phi math and yield math tan left frac Phi 2 right frac 1 sqrt R 1 sqrt R tan left frac delta 2 right math For R 0, no reflection from the first surface and the resultant nonlinear phase shift is equal to the round trip phase change math Phi delta math linear response. However, as can be seen, when R is increased, the nonlinear phase shift math Phi math gives the nonlinear response to math delta math and shows step like behavior. Gires Tournois etalon has applications for laser pulse compression and nonlinear Michelson interferometer . Gires Tournois etalons are clos ... more details
reflectivity. This theoretical approach argues that the shape and feel of human consciousness is heavily ... agent. This is what is meant by self reflectivity. Such reflectivity is encoded in language ... crisis economic, political, cultural . Collective reflectivity emerges then as a function ... construction . In sum, individual self representation, self reference, self reflectivity, and experiences ... . Construction of selves through reflectivity Self reflectivity as a type of consciousness often facililtates ... politics entails at times collective self reflectivity par excellence . In general, such processes ... representation and self reflectivity, for instance through innovations in information and accounting ..., these make for major evolutionary advantages. Oppressive reflectivity The powerful tool of collective reflectivity must be seen as a double edged sword in relation to expanding freedom of opportunity ... variability. Collective representations and reflectivity and directed problem solving based ... evolutionary advantages of human reflectivity must be qualified or viewed as conditional. Outlooks ... verbalized reflectivity monitoring, discussing, judging and re orienting and re organizing self ..., and self referentiality. Collective reflectivity emerges as a function of an organization or group ..., and developing collective being. This reflectivity is encoded in language and developed in conversations ... Individual Selves, Self Awareness, and Reflectivity. Journal of Consciousness Studies , 5 No. 2 ... more details
Wiktionarypar albedo Albedo is a measure of reflectivity Albedo may also refer to Albedo alchemy , a stage of alchemical progression Albedo Ben 10 , a character in the television series Ben 10 Alien Force Albedo toys , a manufacturer Albedo Anthropomorphics , a comic book anthology Albedo role playing game Albedo role playing game , derived from the comics The mesocarp of some Fruit anatomy Mesocarp fruits A character in the video game series List of characters in the Xenosaga series Albedo Xenosaga Albedo 0.39 , an album by the artist Vangelis Albedo One , an Irish horror, fantasy and science fiction magazine founded in 1993 See also Lookfrom Albedo disambig bg es Albedo desambiguaci n it Albedo disambigua ja ... more details
BPR may refer to Business process reengineering Bachelor of Public Relations specific to Mount Saint Vincent University, Halifax, Nova Scotia Bureau of Public Roads, a predecessor of the Federal Highway Administration United States Boston Post Road Beam Profile Reflectometry, using a high numerical aperture lens to measure reflectivity at multiple incident angles simultaneously BPR Global GT Series , an international sports car racing series from the mid 1990s Bellarine Peninsula Railway , a volunteer operated steam driven tourist railway located in Victoria, Australia Blue Planet Registrar Bypass ratio Banque Populaire du Rwanda , a commercial bank in Rwanda disambig de BPR fr BPR it BPR ms BPR nl BPR ... more details
From MoS DAB use ONE LINK per entry, SHORT descriptions. AVOID piping, external links, redlinks with little potential WER or Wer may refer to Lemon technique Weak echo region , in meteorology, an area of markedly lower reflectivity within thunderstorms resulting from an increase in updraft strength Word error rate , in computational linguistics, a common metric of measuring the performance of a speech recognition system Windows Error Reporting , a feature of Windows XP and later operating systems Westlichen Einf hrung der Riedbahn , the western approach of the Riedbahn in Mannheim, Germany Wer god , an Akkadian god Were , an archaic term for adult male humans See also Ver disambiguation Vera disambiguation Vere disambiguation Verus disambiguation Wehr disambiguation disambig de Wer fr WER ko WER it WER scn WER ... more details
Brush Engineered Materials Inc. NYSE BW is a multinational company specializing in high performance engineered materials emphasizing the qualities of strength, reliability, miniaturization and weight savings, thermal dissipation, electrical conductivity and reflectivity. It is particularly well known for its productions of beryllium and beryllium alloy s. The company s engineered materials are used in the telecommunications , computer , automotive electronics , industrial components, aerospace , defense industry defense , and home appliance appliance industries. Brush Engineered Materials Inc. changed its name to Materion Corporation on March 8, 2011, and now trades under the symbol MTRN. ref name BrushHome cite web title Brush Engineered Materials Inc. url http www.materion.com date 2006 07 12 accessdate 2006 12 10 ref References references manufacturing company stub Category Beryllium alloys ... more details
EXC ref http www.bethe salpeter.org http www.bethe salpeter.org ref is a condensed matter physics many body theory Software package installation software package implementing the Bethe Salpeter equation in frequency reciprocal space and on a plane wave basis set. Its purpose is to calculate, ab initio , dielectric and optical properties, like optical absorption absorption , reflectivity , refraction index , electron and X ray Electron energy loss spectroscopy energy loss , for a large variety of systems, ranging from bulk systems, surfaces, to clusters or atoms. It is distributed under the GNU GPL license. See also ABINIT DP code YAMBO code PWscf Quantum chemistry computer programs References references Category Computational physics Physics software is a sub category Categories Category Physics software Category Computational chemistry software ... more details
of the mirror aluminium is the cheapest and most common coating, and yields a reflectivity of around 88 92 over the visible spectrum . More expensive is silver , which has a reflectivity of 95 99 even into the far infrared , but suffers from decreasing reflectivity 90 in the blue and ultraviolet spectral regions. Most expensive is gold , which gives excellent 98 99 reflectivity throughout the infrared , but limited reflectivity at wavelengths shorter than 550 nanometre nm , resulting in the typical ... the reflectivity and increase the transmission of the surface, resulting in a half silvered mirror ... composition, thickness, and number of these layers, it is possible to tailor the reflectivity and transmitivity ... can be reduced to less than 0.2 , producing an antireflection AR coating. Conversely, the reflectivity ... of reflectivity can also be tuned to any particular value, for instance to produce a mirror that reflects ... a protective layer as in silicon dioxide over aluminium , or to enhance the reflectivity of the metal ... 1.38 or silicon dioxide n 1.49 . This periodic system significantly enhances the reflectivity of the surface ... used indices only for quarter wave system , while the maximum reflectivity is increasing nearly ... can achieve 99.9 reflectivity over a broad wavelength range tens of nanometres in the visible spectrum ..., a bandpass or notch filter, or a mirror with a specific reflectivity useful in lasers . For example ... calculator of single layer thin film reflectivity http www.cvimellesgriot.com Products Documents TechnicalGuide ... more details
focuses on updraft s and uses weather radar to measure quantities such as height echo tops , reflectivity ... stronger updrafts. Echo overhang In intense thunderstorms, an area of very strong reflectivity ... echo region WER An area of markedly lower reflectivity, resulting from an increase in updraft strength ... reflectivity, now bounded by an area of high reflectivity. This is observed as a hole in reflectivity ... more details
for other uses DBZ lowercase title dBZ meteorology Technical date July 2011 File Sturmfront auf Doppler Radar Schirm.jpg thumb right The scale of dBZ values can be seen along the bottom of the image. dBZ stands for decibels of Z. It is a meteorology meteorological measure of equivalent reflectivity Z of a radar signal reflected off a remote object. ref http www.srh.noaa.gov jetstream append glossary d.htm NWS JetStream Weather Glossary D s Bot generated title ref The reference level for Z is 1 mm sup 6 sup meter m sup 3 sup , which is equal to 1 m sup 3 sup . It is related to the number of drops per unit volume and the sixth power of drop diameter. Reflectivity of a cloud is dependent on the number and type of hydrometeor s, which includes rain, snow, and hail, and the hydrometeors size. A large number of small hydrometeors will reflect the same as one large hydrometeor. The signal returned to the radar will be equivalent in both situations, so a group of small hydrometeors is virtually indistinguishable from one large hydrometeor on the resulting radar image. A meteorologist can determine the difference between one large hydrometeor and a group of small hydrometeors as well as the type of hydrometeor through knowledge of local weather condition contexts. One dBZ scale of rain 65 Extreme 46 65 heavy 24 45 moderate 8 23 light 0 8 Barely anything dBZ values can be converted to rainfall rates in millimetres per hour using this formula math frac mathrm mm mathrm hr left frac 10 dBZ 24 200 right 5 over 8 math ref cite web url http www.desktopdoppler.com help nws nexrad.htm rainfall 20rates title NWS NEXRAD accessdate November 7, 2010 ref References reflist Decibel state uncollapsed Meteorological equipment state uncollapsed Category Radar meteorology Category Units of measure Climate stub fr D cibel Z pl DBZ ... more details
Unreferenced date December 2009 Orphan date February 2009 Optical Cross Section or OCS is a value which describes the maximum amount of optical flux reflected back to the source. The standard unit of measurement is math frac m 2 sr math . It is dependent on the geometry and the reflectivity at a particular wavelength of an object. Optical cross section is useful in fields such as LIDAR . In the field of Radar this is referred to Radar Cross Section . Object such as license plates on automobiles has a high optical cross section to maximized the laser return to the speed detector gun . Flat mirror Optical cross section of a flat mirror with a given reflectivity at a particular wavelength math r lambda math can be express by this formula. math mbox OCS r lambda frac D 4 1.4884 lambda 2 math Where math D math is the cross sectional diameter of the beam. Note that the direction of the light has to be perpendicular to the mirror surface for this formula to be valid, else the return from the mirror would no longer go back to it source. In order to maximize the return a corner reflector is used. The alignment of a corner reflector with respect to the source is not as critical as the alignment of a flat mirror. Other optical devices Optical cross section is not limited to reflective surfaces. Optical devices such as telescopes and cameras will return some of the optical flux back to the source, since it has optics that reflect some light. The Optical cross section of a camera can vary over time due to the camera shutter opening and closing. See also Radar cross section External links http www.multilingualarchive.com ma enwiki en Optical cross section Optical cross section DEFAULTSORT Optical Cross Section Category Optics ... more details
Unreferenced date September 2007 Image Laser.svg thumb 275px Principal components of a laser br 1. Active laser medium br 2. Laser pumping energy br 3. High reflector br 4. Output coupler br 5. Laser beam An output coupler OC is a partially reflective mirror used in laser s to extract a portion of the laser beam from the optical resonator . Lasers operate by Reflection physics reflecting light between two or more mirrors which have an active laser medium between them. The medium amplifies the light by stimulated emission . For lasing to occur, the gain of the active medium must be larger than the total loss, which includes both unwanted effects such as Absorption electromagnetic radiation absorption , and the intentional release of energy through the output coupler. In other words the laser must attain lasing threshold threshold . There are two important properties of the output coupler Radii of curvature The output coupler may be either flat or Curved mirror curved , depending on the design of the optical cavity. The face of the output coupler facing into the cavity is the side with the applied partially reflective coating. This is the side which partially determines the laser modal properties. If this inner surface is curved then so must be the outer surface. This will stop the OC performing as a lens. The curvature of the outer surface can be designed to give a collimated laser output. This outer surface generally has an anti reflection coating applied to maximise the output power. Reflectance Reflectivity Depending on the gain of the medium, the amount of light the OC needs to reflect back can vary widely. Helium neon laser s require around a 99 reflective mirror to lase, while nitrogen laser s have an extremely high gain they are superradiant and do not require any OC 0 reflective . The reflectivity of any OC will vary with wavelength . A particular mirror may have a tuning range as low as a 10nm or so. For this reason the spectral properties of the OC are impo ... more details
orphan date March 2010 Alexis Spectral Data is a software developed for colour matching processes that calculates from available spectral data the colour numbers used by computers to display colours on screen. It displays the colour for each reflectivity spectral reflectance curve and records the calculated tristimulus trichromatic values and colour numbers along with the spectral curves. This eliminates the need to scan the samples separately with a Truecolour Scanner while creating the database. The spectral data can be introduced manually as a series of reflectivity reflectance values at wavelength s measured in different standard illuminant s with an arbitrary but fixed increment that must be kept for each spectral curve throughout the creation of the whole database. Therefore, older UV VIS spectrophotometry Spectrophotometers that can t be Interface computer science interfaced with computers can also be used for creating the database needed for colour matching. ref Razvan Ion M. Preda, Maria Marcela Savu, Aurelia Meghea, Corneliu Tarabasanu Mihaila, Mathematical model for colour matching applied in sheepskin dyeing , IULTCS Centenary Congress, London 1997, Congress Proceedings, 798 803. ref Alexis Spectral Data determines the whiteness degree in a less time consuming method, which permits storage and easier handling of the obtained data. ref Maria Marcela Savu, Razvan Ion Preda, Florin Vrejoiu, Determination of whiteness degree for various leather support, 11th Congress of the Leather and Shoe Industries, Hungary 1998, 451 ref Alexis Spectral Data can export the tristimulus trichromatic values , calculated from the spectral curves, to Alexis Analyser, software that handles only trichromatic data. The earliest information about the development of this software comes from a paper published by a student at the Politehnica University of Bucharest University Politehnica Bucharest in 1993 ref Razvan Ion M. Preda, Mircea Popescu, True RGB colour analysis , Chemistry a ... more details
Unreferenced stub auto yes date December 2009 Image Specular highlight.jpg frame Specular highlights on a pair of spheres. Specularity is the visual appearance of specular reflections. In computer graphics, it means the quantity used in 3D Rendering computer graphics rendering which represents the amount of specular reflection specular reflectivity a surface has. It is a key component in determining the brightness of specular highlights , along with wikt shininess shininess to determine the size of the specular highlight highlights . It is frequently used in real time computer graphics where the mirror like specular reflection of light from other surfaces is often ignored due to the more intensive computations required to calculate this , and the specular reflection of light direct from point light sources is modelled as specular highlights. See also Ray tracing graphics Reflection mapping Category 3D computer graphics Compu graphics stub de Spekularit t ... more details
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