The prospect of having them back, even spectrally, is tough to resist.
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But there is also something spectrally permanent about the truth: it haunts memory.
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Each night, more footage bloomed: two huge albino manatees, floating spectrally through the nursery.
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I am quite skeptical, in particular of the data processing that can take spectrally sampled data, and infer time variations.
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Each of the plastic models, made by students in Columbia University's Graduate School of Architecture, is spectrally lit with LED lights.
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"The fancy word would be 'spectrally pure,"' he says, with reds and oranges that look like they've been picked out of a box of Crayola crayons.
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In this enhanced color image of the same snapshot, areas that are spectrally redder are made to look, well, red, while areas with less red appear blue.
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From Third World Liberation movements and interracial intimacies to lived and aestheticized experiences of exile and diaspora, the exhibition showcases what remnants and resonances — improbably, imperceptibly, spectrally, or spectacularly — gets through.
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In contrast, Cerio has a few shots from New York City itself, in which the Coney Island Parachute Jump and a Central Park playground are both illuminated spectrally in the night.
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The retention throughout of the brothers' mid-19th-century costumes and their mitteleuropäische accents underlines this sense of continuity; the original Lehmans are spectrally present until a conclusion the audience foresees, even if the characters cannot.
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A huge chunk of lapis lazuli, a lion shot by Teddy Roosevelt, whale earwax, 40,000- to 20,000-year-old mammoth meat and hair, and extinct taxidermy animals, are all spectrally illuminated like relics in the dark galleries.
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To make it work with normal levels of sunlight, the team covered the sponge with a thin sheet of copper covered with a metallic film called a spectrally-selective absorber that absorbs sunlight and traps heat, to help minimize energy loss.
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There's just a whole lot more movement on For Those of You than you might expect from an ambient record, from spectrally swelling synthesizers and gently sequenced electronics, to pieces that sound like sleepwalking club tracks with the drums skillfully excised.
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There were some nods to modern exigencies in the form of houndstooth trouser suits in the same lean, puff-sleeved silhouette and a flirtation with the question of gender identification (those veils hid boys as well as girls), but the mood was almost spectrally mysterious.
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Almost spectrally, the artist's body is omnipresent in the space surrounding the work, effectively activating the environment in which the works are exhibited — like an energy grid, its currents flowing and jumping from one satellite sculpture to the next, providing the centerpiece with the momentum to grow upwards.
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The visuals run without repeating for over two hours, and include footage of him working with Joan Jonas, Theaster Gates and others; video pieces he made with Ms. Walker, Ms. Weems and Lorna Simpson; and photos from his collaborations with others, accompanied by Mr. Moran's piano playing, which wafts up spectrally from the Three Deuces' baby grand (it has player-piano capabilities, so the keys are actually playing themselves).
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When she felt it was necessary, she would incorporate the ouroboros and two human figures, as in the painting "Group VI, Evolution, No. 13" (1908), or a spectrally sectioned pyramid leading to a multi-pointed orb, as in "Group X, No. 1, Altarpiece" (1915), or different squares of color, each paired with a word or containing a symbolic image, as in the watercolors that constitute two of the groups from The Parsifal Series (1916).
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Three strategies have emerged so far: excitation of spectrally separated fluorophores using an emission beamsplitter, using of multiple activators/reporters in STORM mode and ratiometric imaging of spectrally close fluorophores.
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Example of illusory discontinuity stimulus: continuous tone with spectrally remote noise. The tone sounds discontinuous to some listeners. Example of illusory discontinuity stimulus: continuous tone with spectrally remote noise. The tone sounds discontinuous to some listeners.
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Selection of different spectrally selective window coating depends on the ratio of heating versus cooling degree days for the design location.
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In frequency domain OCT (FD-OCT) the broadband interference is acquired with spectrally separated detectors. Two common approaches are swept-source and spectral-domain OCT. A swept source OCT encodes the optical frequency in time with a spectrally scanning source. A spectral domain OCT uses a dispersive detector, like a grating and a linear detector array, to separate the different wavelengths.
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East/west glass doors and windows should be fully shaded top-to-bottom or a spectrally selective coating can be used to reduce solar gain.
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In order to extract the phase information, a carrier fringe pattern is introduced, typically by delaying the two spectrally sheared copies with respect to one another.
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Indoor thermal radiation can also be a disadvantage with spectrally selective (low-e, low-emissivity) glazing. Some insulated glazing systems can double to triple R values.
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Regular subcarrier assignment to generate orthogonal signals There are a variety of orthogonal signal sets used in the field of MIMO radar. One of the proposed signal sets is the spectrally interleaved multi-carrier signal, which is a modified version of orthogonal frequency-division multiplexing signalSturm, Christian, et al. "Spectrally interleaved multi-carrier signals for radar network applications and multi-input multi-output radar." IET Radar, Sonar & Navigation 7.3 (2013): 261-269.. In this approach, the total amount of available subcarriers is distributed among different transmit antennas in an interleaved way.
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D'yakonov was recognized for his pioneering work in the 60s-80s on efficient spectrally equivalent preconditioning for linear systems and eigenvalue problems. In the last decade, strengthened Sobolev spaces became D'yakonov's main topic of research, e.g., (D'yakonov, 2004).
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The dark type of rock has a dark matrix with small, bright, spectrally different inclusions. The inclusions appear similar to CI chondrites. An unanticipated side effect from the Hyabusa 2 thrusters revealed a coating of dark, fine-grained red material.
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When travelling through the material, light will travel partly through the pores, and will thus experience the spectrally sharp gas absorption. Light leaving the material will carry this information, and can be collected by a detector either in a transmission mode (left) or in a reflection mode (right). In order to detect the spectrally sharp fingerprints related to the gas, GASMAS has so far relied on high-resolution tunable diode laser absorption spectroscopy (TDLAS). In principle, this means that a nearly monochromatic (narrow-bandwidth) laser is scanned across an absorption line of the gas, and a detector records the transmission profile.
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A pyranometer is a type of actinometer used for measuring solar irradiance on a planar surface and it is designed to measure the solar radiation flux density (W/m²) from the hemisphere above within a wavelength range 0.3 μm to 3 μm. The name pyranometer stems from the Greek words πῦρ (pyr), meaning "fire", and ἄνω (ano), meaning "above, sky". Class A Fast response and Spectrally flat Pyranometer Spectrally flat Class A thermopile pyranometer A typical pyranometer does not require any power to operate. However, recent technical development includes use of electronics in pyranometers, which do require (low) external power.
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Spectrally, Nereid appears neutral in colour and water ice has been detected on its surface. Its spectrum appears to be intermediate between Uranus's moons Titania and Umbriel, which suggests that Nereid's surface is composed of a mixture of water ice and some spectrally neutral material. The spectrum is markedly different from minor planets of the outer solar system, centaurs Pholus, Chiron and Chariklo, suggesting that Nereid formed around Neptune rather than being a captured body. Halimede, which displays a similar gray neutral colour, may be a fragment of Nereid that was broken off during a collision.
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This method is based on the determination of pixel-level Förster resonance energy transfer (FRET) efficiency in conjunction with spectrally resolved two-photon microscope. The distribution of FRET efficiencies are simulated against different models to get the geometry and stoichiometry of the complexes.
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MLSs are spectrally flat, with the exception of a near-zero DC term. These sequences may be represented as coefficients of irreducible polynomials in a polynomial ring over Z/2Z. Practical applications for MLS include measuring impulse responses (e.g., of room reverberation).
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However, the Xe spectrum is also characterized by many undesirable sharp atomic transitional peaks, making the spectrum less desirable for some spectrally sensitive applications. Metal Halide arc lamp: Primarily developed for use in film and television lighting where a high temporal stability and daylight colour match are required, metal halide arc lamps are also used in solar simulation. QTH: quartz tungsten halogen lamps offer spectra which very closely match black body radiation, although typically with a lower color temperature than the sun. LED: light- emitting diodes have recently been used in research laboratories to construct solar simulators, and may offer promise in the future for energy-efficient production of spectrally tailored artificial sunlight.
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Albedo can affect the electrical energy output of solar photovoltaic devices. For example, the effects of a spectrally responsive albedo are illustrated by the differences between the spectrally weighted albedo of solar photovoltaic technology based on hydrogenated amorphous silicon (a-Si:H) and crystalline silicon (c-Si)-based compared to traditional spectral-integrated albedo predictions. Research showed impacts of over 10%. More recently, the analysis was extended to the effects of spectral bias due to the specular reflectivity of 22 commonly occurring surface materials (both human-made and natural) and analyzes the albedo effects on the performance of seven photovoltaic materials covering three common photovoltaic system topologies: industrial (solar farms), commercial flat rooftops and residential pitched-roof applications.
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An hyperspectral camera in the SWIR region allows such detection by acquiring rapidly spectrally resolved images. The monochromatic full-frame images obtained permit fast identification of chemical compounds. Detection of sulfur by laser-induced breakdown spectroscopy (LIBS) can also be easily achieved with holographic Bragg grating used as filtering elements.
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Electrical resistance is reduced within the channel, and current flows between the electrodes. # Initial phase: the bulb is driven with controlled overload. Because the arc is operated at high power, the temperature in the capsule rises quickly. The metallic salts vaporize, and the arc is intensified and made spectrally more complete.
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It contained a photo montage of women with their eyes scratched out; as the killer's trademark in the film was to remove the eyes of his victims. Cooper then shot these images submerged in water, to give them an added layer of distance and make them ripple spectrally on the screen.
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Part 5: Ultra Wideband Update: IEEE 802.15.4a and Ecma-368 Podcast As was mentioned above, the Direct Sequence UWB PHY was the one that ended up being added into the IEEE 802.15.4a standard. Direct Sequence UWB is spectrally efficient, can support precision ranging, and is very robust even at low transmit powers.
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Tungsten film is photographic film designed to accurately represent colors as perceived by humans under tungsten light; the more usual color films are "daylight films", balanced to produce accurate colours under direct light from the sun or electronic flash. Tungsten film was developed for photographers who use tungsten lights, also known as photofloods, which have a much lower color temperature than daylight, at 3200 kelvins. It also renders colors more accurately than daylight film under ordinary household incandescent lighting. On daylight-balanced film tungsten lighting produces a spectrally accurate rendition of a scene; but human vision adjusts to the color of the lighting and perceives colors as if under daylight, seeing a spectrally accurate image as having a yellow-orange cast.
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FROG, however, solved the problem by measuring an "auto-spectrogram" of the pulse, in which the pulse gates itself in a nonlinear-optical medium and the resulting gated piece of the pulse is then spectrally resolved as a function of the delay between the two pulses. Retrieval of the pulse from its FROG trace is accomplished by using a two-dimensional phase-retrieval algorithm. FROG is currently the standard technique for measuring ultrashort laser pulses, and also popular, replacing an older method called autocorrelation, which only gave a rough estimate for the pulse length. FROG is simply a spectrally resolved autocorrelation, which allows the use of a phase-retrieval algorithm to retrieve the precise pulse intensity and phase vs. time.
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The effectiveness of direct solar gain systems is significantly enhanced by insulative (e.g. double glazing), spectrally selective glazing (low-e), or movable window insulation (window quilts, bifold interior insulation shutters, shades, etc.). Generally, Equator-facing windows should not employ glazing coatings that inhibit solar gain. There is extensive use of super-insulated windows in the German Passive House standard.
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Nix has an elongated shape, with its longest axis measured at across and its shortest axis across. This gives Nix the measured dimensions of . Early research appeared to show that the surface of Nix is reddish in color. Contrary to this, other studies show that Nix is spectrally neutral, similar to the small moons of Pluto.
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Sun photometer CIMEL 318A in Tõravere. A sun photometer is a type of photometer conceived in such a way that it points at the sun. Recent sun photometers are automated instruments incorporating a sun-tracking unit, an appropriate optical system, a spectrally filtering device, a photodetector, and a data acquisition system. The measured quantity is called direct-sun radiance.
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As described here, white light interferometry is a non-contact optical method for surface height measurement on 3-D structures with surface profiles varying between tens of nanometers and a few centimeters. It is often used as an alternative name for coherence scanning interferometry in the context of areal surface topography instrumentation that relies on spectrally-broadband, visible-wavelength light (white light).
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Had the policy been implemented, DOE could have paid back the investment in energy conservation and renewable energy generation within two years. DOE spent millions of dollars in the 1990s to develop and make commercially available "spectrally enhanced lighting" that mimicked sunlight but required 50 percent less energy to use,Holusha, John. "Light Source To Replace Many Bulbs." New York Times.
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In 1994, Eastman Kodak stopped making all materials for this process. The dyes used in the process are very spectrally pure compared to normal coupler-induced photographic dyes, with the exception of the Kodak cyan. The dyes have excellent light and dark fastness. The dye transfer process possesses a larger color gamut and tonal scale than any other process, including inkjet.
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As with chondritic meteoroids, particles contain Fe(Ni) sulfide and GEMS (glass with embedded metal and sulfides) Various amounts of organics (CHON) are present. Though organics are cosmically abundant, and were widely predicted to exist in comets, they are spectrally indistinct in most telescopes. Organics were only confirmed via mass spectrometry during the Halley flybys. Some organics are in the form of PAHs (Polycyclic Aromatic Hydrocarbons).
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Undoped and tungsten-doped vanadium dioxide films can act as "spectrally-selective" coatings to block infrared transmission and reduce the loss of building interior heat through windows.Guzman, G. Vanadium dioxide as infrared active coating. solgel.com Varying the amount of tungsten allows regulating the phase transition temperature at a rate of 20 °C per 1 atomic percent of tungsten. The coating has a slight yellow-green color.
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Super-resolution in fluorescence, more specifically, refers to the ability of a microscope to prevent the simultaneous fluorescence of adjacent spectrally identical fluorophores. This process effectively sharpens the point-spread function of the microscope. Examples of recently developed super-resolution fluorescent microscope methods include stimulated emission depletion (STED) microscopy, saturated structured-illumination microscopy (SSIM), fluorescence photoactivation localization microscopy (FPALM), and stochastic optical reconstruction microscopy (STORM).
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Figure 1 shows a particular implementation format of the Synthetic Array method. This implementation is called "Rainbow Heterodyne Detection" because the local oscillator has its frequencies spread out like a rainbow across the surface of the detector. The output from the detector is a multi-frequency signal. If this output signal is spectrally resolved then each different electrical frequency corresponds to a different location on the detector.
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Video spectroscopy combines spectroscopic measurements with video technique. This technology has resulted from recent developments in hyperspectral imaging. A video capable imaging spectrometer can work like a camcorder and provide full frame spectral images in real-time that enables advanced (vehicle based) mobility and hand-held imaging spectroscopy. Unlike hyperspectral line scanners, a video spectrometer can spectrally capture randomly and quickly moving objects and processes.
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Another was offered by ARM Holdings. Speed advantages have not materialized, because modern computer designs already run at the speed of their slowest component, usually memory. These do use somewhat less power because a clock distribution network is not needed. An unexpected advantage is that asynchronous computers do not produce spectrally-pure radio noise, so they are used in some mobile-phone base-station controllers.
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A basic IBBCEAS setup consists of an incoherent light source, collimation optics, the absorber of interest and a detector. The incoherent source of radiation is spectrally filtered to match the bandwidth of the high reflectivity cavity mirrors. The filtered light is passively coupled into a stable optical cavity formed by two mirrors. Due to the high reflectivity of the mirrors effective absorption path lengths can reach a few kilometres.
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Acridine orange (AO) is a nucleic acid selective fluorescent cationic dye useful for cell cycle determination. It is cell-permeable, and interacts with DNA and RNA by intercalation or electrostatic attractions. When bound to DNA, it is very similar spectrally to fluorescein. Like fluorescein, it is also useful as a non-specific stain for backlighting conventionally stained cells on the surface of a solid sample of tissue (fluorescence backlighted staining).
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Their 1985 technique of chirped pulse amplification stretched out each laser pulse both spectrally and in time before amplifying it, then compressed each pulse back to its original duration, generating ultrashort optical pulses of terawatt to petawatt intensity. Using chirped pulse amplification allowed smaller high-power laser systems to be built on a typical laboratory optical table, as "table-top terawatt lasers". The work received the 2018 Nobel Prize in Physics.
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Under the SMASS classification taxonomy, this asteroid is listed as a B-type; a group that combines both the Tholen B and F types. The spectrum of this object suggests the presence of magnetite (Fe3O4), which gives it the spectrally-blue coloration that is a characteristic of this SMASS class. The spectrum of this asteroid also displays a band feature near 2.9 μm that indicate the presence of a hydrated mineral.
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Part 604 describes a class of optical surface measurement methods wherein the localization of interference fringes during a scan of optical path length provides a means to determine surface characteristics such as topography, transparent film structure, and optical properties. The technique encompasses instruments that use spectrally broadband, visible sources (white light) to achieve interference fringe localization). CSI uses either fringe localization alone or in combination with interference fringe phase.
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Her doctoral research entailed mapping functional specialization in mammalian brains. Tanner's dissertation was titled "Cat"-ology: spectrally resolved neurophotonics in the mammalian brain and phantom studies. She conducted post- doctoral training at the University of California, Irvine specializing in dynamic imaging of thick tissues. She then became a Department of Defense Breast Cancer Post-doctoral fellow jointly at University of California, Berkeley and Lawrence Berkeley National Laboratory under Mina Bissell.
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Minimum frequency-shift keying or minimum-shift keying (MSK) is a particular spectrally efficient form of coherent FSK. In MSK, the difference between the higher and lower frequency is identical to half the bit rate. Consequently, the waveforms that represent a 0 and a 1 bit differ by exactly half a carrier period. The maximum frequency deviation is δ = 0.25 fm, where fm is the maximum modulating frequency.
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Additionally, the emitted sound from the instrument was recorded, under controlled conditions, and spectrally analyzed. Major findings include the concentration of the emitted sound between 400 Hz and 800 Hz, with an amplitude modified in a manner consistent with the experimentally measured vibrational characteristics of the instrument’s sound box and bridge. The experimental results validate the historical evidence that chelys was used in Greek antiquity as an accompaniment instrument to the human voice.
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The creation of these finely spaced levels does not require increasing the optical microcavity dimensions. Hence, these finely spaced levels do not affect the optomechanical interaction strength in a significant degree. The approach uses intermodal coupling, induced by radiation pressure and can also provide a spectrally selective mean to detect phonons. Moreover, some evidences of intermodal cooling are observed in this kind of experiments and thus, there is an interest in optomechanical cooling.
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A variety of terms are used in the literature to describe these cells, including chromatically opposed or -opponent, spectrally opposed or -opponent, opponent colour, colour opponent, opponent response, and simply, opponent cell. The opponent color theory can be applied to computer vision and implemented as the Gaussian color model and the natural-vision-processing model.Barghout, Lauren. (2014). "Visual taxometric approach to image segmentation using fuzzy-spatial taxon cut yields contextually relevant regions".
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Acridine orange is an organic compound that serves as a nucleic acid-selective fluorescent dye with cationic properties useful for cell cycle determination. Acridine orange is cell-permeable, which allows the dye to interact with DNA by intercalation, or RNA via electrostatic attractions. When bound to DNA, acridine orange is very similar spectrally to an organic compound known as fluorescein. Acridine orange and fluorescein have a maximum excitation at 502nm and 525 nm (green).
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The action of H2O2 may have dominated temporally given the drastic reduction in aqueous and igneous activity in this recent era, making the observed Fe3+ oxides volumetrically small, though pervasive and spectrally dominant. Nevertheless, aquifers may have driven sustained, but highly localized surface water in recent geologic history, as evident in the geomorphology of craters such as Mojave. Furthermore, the Lafayette Martian meteorite shows evidence of aqueous alteration as recently as 650 Ma.
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On the other hand, Steve Zelditch proved that the answer to Kac's question is positive if one imposes restrictions to certain convex planar regions with analytic boundary. It is not known whether two non-convex analytic domains can have the same eigenvalues. It is known that the set of domains isospectral with a given one is compact in the C∞ topology. Moreover, the sphere (for instance) is spectrally rigid, by Cheng's eigenvalue comparison theorem.
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The Spectrally Agile Frequency-Incrementing Reconfigurable (SAFIRE) radar is a vehicle-mounted, forward-looking ground-penetrating radar (FLGPR) system designed to detect buried or hidden explosive hazards. It was developed by the U.S. Army Research Laboratory (ARL) in 2016 as part of a long generation of ultra-wideband (UWB) and synthetic aperture radar (SAR) systems created to combat buried landmines and IEDs. Past iterations include the railSAR, the boomSAR, and the SIRE radar.
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But that method also changes the frequency content of the signal by an effect called spectral leakage. Window functions allow us to distribute the leakage spectrally in different ways, according to the needs of the particular application. There are many choices detailed in this article, but many of the differences are so subtle as to be insignificant in practice. In typical applications, the window functions used are non-negative, smooth, "bell-shaped" curves.
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Figure 1. "The setting sun dimmed by dense haze over State College, Pennsylvania on 16 September 1992". Haze can be defined as an aerial form of the Tyndall effect therefore unlike other atmospheric effects such as cloud and fog, haze is spectrally selective: shorter (blue) wavelengths are scattered more, and longer (red/infrared) wavelengths are scattered less. For this reason, many super-telephoto lenses often incorporate yellow filters or coatings to enhance image contrast.
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It is a spectrally resolved autocorrelation. The algorithm that extracts the intensity and phase from a FROG trace is iterative. Grating-eliminated no-nonsense observation of ultrafast incident laser light e-fields (GRENOUILLE) is a simplified version of FROG. (Grenouille is French for "frog".) Chirp scan is a technique similar to MIIPS which measures the spectral phase of a pulse by applying a ramp of quadratic spectral phases and measuring second harmonic spectra.
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There may also be positive contributions to \Delta \alpha spectrally near the original absorption line due to resonance broadening and at other spectral positions due to excited-state absorption, i.e., optical transitions to states such as biexcitons which are only possible if the system is in an excited state. The bleaching and the positive contributions are generally present in both coherent and incoherent situations where the polarization vanishes but occupations in excited states are present. For detuned pumping, i.e.
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Before OSIRIS-REx, spectroscopy indicated a correspondence with the CI and/or CM carbonaceous chondrite meteorites, including carbonaceous-chondrite mineral magnetite. Magnetite, a spectrally prominent water product but destroyed by heat, is an important proxy of astronomers including OSIRIS-REx staff. Preliminary spectroscopic surveys of the asteroid's surface by OSIRIS-REx then confirmed magnetite and the meteorite- asteroid linkage,All About Bennu: A Rubble Pile with a Lot of Surprises. Kimberly M. S. Cartier, EOS Planetary Sciences.
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So, the heat transfer between two surfaces relies on both the view factor and the angle of reflected radiation. It was also assumed that the surface is a gray body, that is to say its emissivity is independent of radiation frequency or wavelength. However, if the range of radiation spectrum is large, this will not be the case. In such an application, the radiosity must be calculated spectrally and then integrated over the range of radiation spectrum.
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Echelle spectrometer: The first standard grating is optimized for a single lower order, while multiple higher orders of the echelle have an optimized output intensity. Both diffractive elements are mounted orthogonally in such a way that the highly illuminated orders of the echelle are transversally separated. Since only parts of the full spectrum of each individual order lie in the illuminated region, only portions of the different orders overlap spectrally (i.e. green line in red portion).
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DIDO implements a spectral algorithm based on pseudospectral optimal control theory founded by Ross and his associates. The covector mapping principle of Ross and Fahroo eliminates the curse of sensitivity associated in solving for the costates in optimal control problems. DIDO generates spectrally accurate solutions whose extremality can be verified using Pontryagin's Minimum Principle. Because no knowledge of pseudospectral methods is necessary to use it, DIDO is often used as a fundamental mathematical tool for solving optimal control problems.
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R-type asteroids are moderately bright, relatively uncommon inner-belt asteroids that are spectrally intermediate between the V and A-type asteroids. The spectrum shows distinct olivine and pyroxene features at 1 and 2 micrometres, with a possibility of plagioclase. Shortwards of 0.7 μm the spectrum is very reddish. The IRAS mission has classified 4 Vesta, 246 Asporina, 349 Dembowska, 571 Dulcinea and 937 Bethgea as type R; however, the re-classification of Vesta, the V archetype, is debatable.
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Pallas, the largest B-type asteroid. B-type asteroids are a relatively uncommon type of carbonaceous asteroid, falling into the wider C-group; the 'B' indicates these objects are spectrally blue. In the asteroid population, B-class objects can be found in the outer asteroid belt, and also dominate the high-inclination Pallas family which includes the second-largest asteroid 2 Pallas. They are thought to be primitive, volatile-rich remnants from the early Solar System.
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In the laboratory, Baker conducted experiments on the aesthetics of colours. She published two of her experiments in the laboratory's in-house publication, called the University of Toronto Studies, Psychological Series: first, “Experiments on the aesthetic of light and colour: On combinations of two colours," and second, “Experiments on the aesthetic of light and colour: Spectrally pure colours in binary combinations." Baker's doctoral dissertation consisted of the two reports. She was awarded her Ph.D. in 1903.
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Adelaide was a key part of many illusions, performing as a levitating sleeper, a human cannonball, a bicycle rider who carried a girl on her shoulders, and a dancer who spectrally swirled in red silk like a pillar of fire. The Herrmanns toured the United States, Mexico, South America, and Europe. In 1888, the Herrmanns put on a show wherein they revealed how the spiritualist Ann O'Delia Diss Debar was a fraudulent medium in front of journalists.
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The average fluid temperature can be between 25°C in swimming pool applications to 90°C in solar cooling systems. Covered PVT collectors resemble the form and design of conventional flat plate collectors or evacuated vacuum tubes. Yet, PV cells instead of spectrally-selective absorber coatings absorb the incident solar irradiance and generate an electrical current in addition to solar heat. The insulating characteristics of the front cover increase the thermal efficiency and allow for higher operating temperatures.
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They also have a role in reducing heat losses in cool climates. However, much greater insulation can be achieved through the addition of bulk insulators (see above). Some radiant barriers are spectrally selective and will preferentially reduce the flow of infra-red radiation in comparison to other wavelengths. For instance low-emissivity (low-e) windows will transmit light and short-wave infra-red energy into a building but reflect the long- wave infra-red radiation generated by interior furnishings.
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The final data product that MSE will deliver are 2-dimensional images of spectra, and 1-dimensional spectra, corrected for observatory signature, spectrally calibrated, and co-added where multiple measurements of the same object at the same resolution have been made. The data release policy will be finalized as the project approaches the start of construction, and is expected to include an immediate release of data to partner organization scientists and survey teams, and a later release to the public.
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During this eruption it increase in brightness by 10 mag, or by about a factor of . The star then rapidly subsided in brightness through the period spectrally observed by Mason et al. Prior to outburst, the star's magnitude had a period of around 1.4 days that decreased exponentially until the outburst. Following the model of a typical contact binary, V1309 Scorpii had two peaks in magnitude per cycle, corresponding to times when the two stars were perpendicular to the observer's line of sight.
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The emission directly after the excitation is spectrally very broad, yet still centered in the vicinity of the strongest exciton resonance. As the carrier distribution relaxes and cools, the width of the PL peak decreases and the emission energy shifts to match the ground state of the exciton (such as an electron) for ideal samples without disorder. The PL spectrum approaches its quasi-steady-state shape defined by the distribution of electrons and holes. Increasing the excitation density will change the emission spectra.
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Furthermore, Low-emissivity glazing which is spectrally selective in order to minimize solar heat gain is installed across the building. The apartment block is located on an east–west axis, exactly 1 km east of the Prime Meridian. The apartments on the north side overlook Royal Victoria Dock and the ExCeL Exhibition Centre, while apartments on the south side do not overlook the River Thames at all. Eastern Quay won various awards from construction, including one from the Chartered Institute of Building.
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Instead, expensive lenses made of quartz must be used. Infrared films may be shot in standard cameras using an infrared pass filters, although focus must compensate for the infrared focal point. A converted digital camera usually requires that the infrared hot mirror be removed and replaced by a wideband, spectrally flat glass of the same optical path length. Typical glass types used include Schott WG-280 and BK-7, which transmit as much as 90% from around 300 nm to past 1000 nm.
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The compound eyes of Bombus hortorum are two dark, oval structures situated on the dorsal-ventral axis of their head. They lack interfacetal hairs and feature a relatively thick cornea and large retinal cells. Three types of spectrally sensitive cells were identified: UV with peak sensitivity to light of 353 nm wavelength, blue and green sensitive receptors with peak sensitivities to wavelengths of 430 nm and 548 nm, respectively. The ratios of these three cell types were 1:1:6.
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The ratio of the photocurrents from the 830 nm and 940 nm LEDs provides total water vapor. F. M. Mims III, Sun Photometer with Light-Emitting Diodes as Spectrally Selective Detectors, Applied Optics, 31, 33, 6965-6967, 1992. Total Ozone measured by Forrest M. Mims III at Geronimo Creek Observatory, Texas (1990-2016) The chart at right shows the total ozone measured from 1990 through 2016. Total ozone (Dobson units) measured at solar noon at Geronimo Creek Observatory since February 4, 1990.
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Most RLPs are NAK-based, meaning that forward-link sender assumes that each transmission got through, and the receiver only NAKs when an out-of- order segment is received. This greatly reduces reverse-link transmissions, which are spectrally inefficient and have a longer latency on most cellular networks. When the transmit pipeline goes idle, a NAK-based RLP must eventually retransmit the last segment a second time, in case the last fragment was lost, to reach a .01% packet loss rate.
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Twede, David. Introduction to Full-Spectrum and Infrared photography. surrealcolor.110mb.com Replacing a hot mirror or infrared blocking filter with an infrared pass or a wide spectrally transmitting filter allows the camera to detect the wider spectrum light at greater sensitivity. Without the hot-mirror, the red, green and blue (or cyan, yellow and magenta) colored micro-filters placed over the sensor elements pass varying amounts of ultraviolet (blue window) and infrared (primarily red and somewhat lesser the green and blue micro-filters).
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The most useful feature of the LSSA method is enabling incomplete records to be spectrally analyzed, without the need to manipulate the record or to invent otherwise non-existent data. Magnitudes in the LSSA spectrum depict the contribution of a frequency or period to the variance of the time series. Generally, spectral magnitudes defined in the above manner enable the output's straightforward significance level regime.Beard, A.G., Williams, P.J.S., Mitchell, N.J. & Muller, H.G. A special climatology of planetary waves and tidal variability, J Atm.
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The two species are labeled with dyes of spectrally resolved (>50 nm) colors, e.g. cyanine-3 and cyanine-5. Fluorescence excitation is typically carried out in total internal reflection mode which increases the signal-to-noise ratio for the molecules at the surface with respect to the molecules in bulk solution. The molecules are detected as spots appearing on the surface in real-time, and their locations are found to within 10-20 nm by fitting of point-spread functions.
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In 1859, not knowing of Stewart's work, Gustav Robert Kirchhoff reported the coincidence of the wavelengths of spectrally resolved lines of absorption and of emission of visible light. Importantly for thermal physics, he also observed that bright lines or dark lines were apparent depending on the temperature difference between emitter and absorber. Kirchhoff then went on to consider some bodies that emit and absorb heat radiation, in an opaque enclosure or cavity, in equilibrium at temperature . Here is used a notation different from Kirchhoff's.
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Makemake has been shown to possess a number of hydrocarbons derived from the radiation- processing of methane, including ethane, ethylene and acetylene. Although to date most KBOs still appear spectrally featureless due to their faintness, there have been a number of successes in determining their composition. In 1996, Robert H. Brown et al. acquired spectroscopic data on the KBO 1993 SC, which revealed that its surface composition is markedly similar to that of Pluto, as well as Neptune's moon Triton, with large amounts of methane ice.
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In this case, it may be a candidate for the parent body of the mesosiderites, a class of stony–iron meteorites. Another possibility is that Psyche may be an endmember of diverse relic bodies left by the inner planet formation. The asteroid's mantle may have been stripped away not by a single collision but by multiple ( > 3 ) relatively slow side-swipe collisions with bodies of comparable or larger size. What is left is a metallic core covered by a thin layer of silicates, which reveals itself spectrally.
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Radial basis function (RBF) interpolation is an advanced method in approximation theory for constructing high-order accurate interpolants of unstructured data, possibly in high-dimensional spaces. The interpolant takes the form of a weighted sum of radial basis functions. RBF interpolation is a mesh-free method, meaning the nodes (points in the domain) need not lie on a structured grid, and does not require the formation of a mesh. It is often spectrally accurate and stable for large numbers of nodes even in high dimensions.
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These are all defined in ISO 9060. For a sensor to be classified in a certain category, it needs to fulfill all the minimum requirements for these properties. Further additional classes are defined by adding the term "spectrally flat radiometer", this is allowed if the pyranometer has a spectral selectivity of less than 3% in the 0,35 to 1,5 μm spectral range The calibration is typically done having the World Radiometric ReferenceWorld Radiometric Reference (WRR) as an absolute reference. It is maintained by PMODPMOD in Davos, Switzerland.
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The early Noachian era was characterized by atmospheric loss to space from heavy meteoritic bombardment and hydrodynamic escape. Ejection by meteorites may have removed ~60% of the early atmosphere. Significant quantities of phyllosilicates may have formed during this period requiring a sufficiently dense atmosphere to sustain surface water, as the spectrally dominant phyllosilicate group, smectite, suggests moderate water-to-rock ratios. However, the pH-pCO2 between smectite and carbonate show that the precipitation of smectite would constrain pCO2 to a value not more than .
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Figure 10: Waves of different frequencies interfere to form a localized pulse if they are coherent. Figure 11: Spectrally incoherent light interferes to form continuous light with a randomly varying phase and amplitude Waves of different frequencies (in light these are different colours) can interfere to form a pulse if they have a fixed relative phase- relationship (see Fourier transform). Conversely, if waves of different frequencies are not coherent, then, when combined, they create a wave that is continuous in time (e.g. white light or white noise).
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Tau Ceti, Latinized from τ Ceti, is a single star in the constellation Cetus that is spectrally similar to the Sun, although it has only about 78% of the Sun's mass. At a distance of just under from the Solar System, it is a relatively nearby star and the closest solitary G-class star. The star appears stable, with little stellar variation, and is metal-deficient. Observations have detected more than ten times as much dust surrounding Tau Ceti as is present in the Solar System.
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Amplitude modulation spectra (left) and frequency modulation spectra (right), calculated on a corpus of English or French sentences. The ENVp plays a critical role in many aspects of auditory perception, including in the perception of speech and music. Speech recognition is possible using cues related to the ENVp, even in situations where the original spectral information and TFSp are highly degraded. Indeed, when the spectrally local TFSp from one sentence is combined with the ENVp from a second sentence, only the words of the second sentence are heard.
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Pasiphae observed by the Wide-field Infrared Survey Explorer (WISE) spacecraft in 2014 With diameter estimated at 60 km Pasiphae is the largest retrograde and third largest irregular satellite after Himalia and Elara. Spectroscopical measurements in infrared indicate that Pasiphae is a spectrally featureless object, consistent with the suspected asteroidal origin of the object. Pasiphae is believed to be a fragment from a captured asteroid along with other Pasiphae group satellites.Sheppard, S. S.; and Jewitt, D. C.; An Abundant Population of Small Irregular Satellites Around Jupiter , Nature, Vol.
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On August 28, 1993, Galileo flew within of the asteroid 243 Ida. The probe discovered that Ida had a small moon, dubbed Dactyl, measuring around in diameter; this was the first asteroid moon discovered. Measurements using Galileo Solid State Imager, Magnetometer and NIMS instrument were taken. From subsequent analysis of this data, Dactyl appears to be an SII-subtype S-type asteroid, and is spectrally different from 243 Ida. It is hypothesized that Dactyl may have been produced by partial melting within a Koronis parent body, while the 243 Ida region escaped such igneous processing.
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Unusually, a total of 15 of the 23 brightest stars in Crux are spectrally blue-white B-type stars. Among the five main bright stars, Delta, and probably Alpha and Beta, are likely co- moving B-type members of the Scorpius–Centaurus Association, the nearest OB association to the Sun. They are among the highest-mass stellar members of the Lower Centaurus-Crux subgroup of the association, with ages of roughly 10 to 20 million years. Other members include the blue-white stars Zeta, Lambda and both the components of the visual double star, Mu.
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After measurement, an algorithm is used to convert the multiplexed (overlapped) two-dimensional data into the three-dimensional datacube (spectrally resolved image). Conceptually, one can consider each of the dispersed images on the detector as a 2D projection of the 3D datacube, in a manner analogous to the way in which X-ray projections measured by medical computed tomography instruments are used to estimate the 3D volume distribution within a patient's body.Michael Descour and Eustace Dereniak, "Computed-tomography imaging spectrometer: experimental calibration and reconstruction results", Applied Optics 34: 4817-4826 (1995).
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Silvered film may also be employed to the same end. Spectrally selective films act by blocking certain wavelengths of the sun's infrared radiation and reject heat without reducing natural light. Security films are applied to glass so when the glass is broken it holds together, preventing dangerous shards from flying about, or to make it more difficult for an intruder to gain entry. Typically applied to commercial glass, these films are made of heavy-gauge plastic and are intended to maintain the integrity of glass when subject to heavy impact.
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On-off keying is most commonly used to transmit Morse code over radio frequencies (referred to as CW (continuous wave) operation), although in principle any digital encoding scheme may be used. OOK has been used in the ISM bands to transfer data between computers, for example. OOK is more spectrally efficient than frequency-shift keying, but more sensitive to noise when using a regenerative receiver or a poorly implemented superheterodyne receiver. For a given data rate, the bandwidth of a BPSK (Binary Phase Shift keying) signal and the bandwidth of OOK signal are equal.
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MMN is evoked by an infrequently presented stimulus ("deviant"), differing from the frequently- occurring stimuli ("standards") in one or several physical parameters like duration, intensity, or frequency. In addition, it is generated by a change in spectrally complex stimuli like phonemes, in synthesised instrumental tones, or in the spectral component of tone timbre. Also the temporal order reversals elicit an MMN when successive sound elements differ either in frequency, intensity, or duration. The MMN is not elicited by stimuli with deviant stimulus parameters when they are presented without the intervening standards.
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Q-type asteroids are relatively uncommon inner-belt asteroids with a strong, broad 1 micrometre olivine and pyroxene feature, and a spectral slope that indicates the presence of metal. There are absorption features shortwards and longwards of 0.7 μm, and the spectrum is generally intermediate between the V and S-type. Q-type asteroids are spectrally more similar to ordinary chondrite meteorites (types H, L, LL) than any other asteroid type. This has led scientists to speculate that they are abundant, but only about 20 of this type has been characterized.
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Chimeric channelrhodopsins have been developed by combining transmembrane helices from ChR1 and VChR1, leading to the development of ChRs with red spectral shifts (such as C1V1 and ReaChR). ReaChR has improved membrane trafficking and strong expression in mammalian cells, and has been used for minimally invasive, transcranial activation of brainstem motoneurons. Searches for homologous sequences in other organisms has yielded spectrally improved and stronger red- shifted channelrhodpsins (Chrimson). In combination with ChR2, these yellow/red light-sensitive channelrhodopsins allow controlling two populations of neurons independently with light pulses of different colors.
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When mixing colored light (additive color models), the achromatic mixture of spectrally balanced red, green, and blue (RGB) is always white, not gray or black. When we mix colorants, such as the pigments in paint mixtures, a color is produced which is always darker and lower in chroma, or saturation, than the parent colors. This moves the mixed color toward a neutral color—a gray or near-black. Lights are made brighter or dimmer by adjusting their brightness, or energy level; in painting, lightness is adjusted through mixture with white, black, or a color's complement.
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A third version of the beam splitter is a dichroic mirrored prism assembly which uses dichroic optical coatings to divide an incoming light beam into a number of spectrally distinct output beams. Such a device was used in three-pickup-tube color television cameras and the three-strip Technicolor movie camera. It is currently used in modern three-CCD cameras. An optically similar system is used in reverse as a beam-combiner in three-LCD projectors, in which light from three separate monochrome LCD displays is combined into a single full- color image for projection.
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The double integration corrects for the -ω² filtering characteristic associated with the nonlinear acoustic effect. This recovers the scaled original spectrum at baseband. The harmonic distortion process has to do with the high frequency replicas associated with each squaring demodulation, for either modulation scheme. These iteratively demodulate and self-modulate, adding a spectrally smeared out and time exponentiated copy of the original signal to baseband and twice the original center frequency each time, with one iteration corresponding to one traversal of the space between the emitter and target.
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The original CIECAM97s color appearance model uses the Bradford transformation matrix (MBFD) (as does the LLAB color appearance model). This is a “spectrally sharpened” transformation matrix (i.e. the L and M cone response curves are narrower and more distinct from each other). The Bradford transformation matrix was supposed to work in conjunction with a modified von Kries transform method which introduced a small non-linearity in the S (blue) channel. However, outside of CIECAM97s and LLAB this is often neglected and the Bradford transformation matrix is used in conjunction with the linear von Kries transform method, explicitly so in ICC profiles.
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It is orbiting at a distance of 2.419 times the separation of the Earth from the Sun, with an orbital period of 3.76 years and an eccentricity of 0.14. In the Tholen classification scheme, Polana is a primitive carbonaceous asteroid of type F, which is a subdivision of more common C-type. Under the SMASS classification taxonomy, Polana is listed as a B-type asteroid; a group that combines both the Tholen B and F types. The spectrum of this object suggests the presence of magnetite (Fe3O4), which gives it the spectrally blue coloration that is a characteristic of this SMASS class.
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The Coloroid color space, showing the cylindrical geometry of luminosity (V), hue (A) and saturation (T), the relative components of pure hue (p), white (w) and black (s) that can be used to mix any hue within a single hue plane, and the relative areas of all possible (spectrally defined) colors and material (pigmented surfaces) colors. The Coloroid Color System is a color space developed between 1962 and 1980 by Prof. Antal Nemcsics at the Budapest University of Technology and Economics for use by "architects and visual constructors". Since August 2000, the Coloroid has been registered as Hungarian Standard MSZ 7300.
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OSIRIS (Optical Spectrograph and InfraRed Imager System) is an instrument that measures vertical profiles of spectrally dispersed, limb scattered sunlight from the upper troposphere into the lower mesosphere. OSIRIS is one of two instruments on the Odin satellite, launched February, 2001 (the other instrument being a sub-mm radiometer) into a sun-synchronous, 6 pm/6 am local time orbit at 600 km. This restricts OSIRIS sunlit observations to the Northern hemisphere in May, June, July August and the Southern hemisphere in November, December, January and February. Global coverage from 82°S to 82°N occurs on the months adjoining the equinoxes.
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For a time sequence of color images, the array is generally four-dimensional, with the dimensions representing image X and Y coordinates, time, and RGB (or other color space) color plane. For example, the EarthServer initiative unites data centers from different continents offering 3-D x/y/t satellite image timeseries and 4-D x/y/z/t weather data for retrieval and server-side processing through the Open Geospatial Consortium WCPS geo datacube query language standard. A data cube is also used in the field of imaging spectroscopy, since a spectrally-resolved image is represented as a three- dimensional volume.
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The kilometric radiation is thought to be generated by the Cyclotron Maser Instability of the electrons moving along magnetic field lines related to the auroral regions of Saturn.Kurth, 2009, pp. 341–348 Thus the SKR is related to the auroras around the poles of the planet. The radiation itself comprises spectrally diffuse emissions as well as narrowband tones with bandwidths as narrow as 200 Hz. In the frequency–time plane arc like features are often observed, much like in the case of the Jovian kilometric radiation. The total power of the SKR is around 1 GW.Zarka, 2005, pp.
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The MIIPS method is also based on second-harmonic generation (SHG) in a non-linear crystal; however, instead of temporally scanning a replica of the pulse as in autocorrelation, a controllable and varying GDD is applied to the pulse through a pulse shaper. The intensity is maximal when the outgoing pulse is unchirped, or when the applied GDD exactly compensates the incoming pulse GDD. The pulse GDD is thus measured and compensated. By spectrally resolving the SHG signal, GDD can be measured as a function of frequency, so that the spectral phase can be measured and dispersion can be compensated to all orders.
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Spectral karyogram of a human female Multicolor FISH and the older spectral karyotyping are molecular cytogenetic techniques used to simultaneously visualize all the pairs of chromosomes in an organism in different colors. Fluorescently labeled probes for each chromosome are made by labeling chromosome-specific DNA with different fluorophores. Because there are a limited number of spectrally distinct fluorophores, a combinatorial labeling method is used to generate many different colors. Fluorophore combinations are captured and analyzed by a fluorescence microscope using up to 7 narrow-banded fluorescence filters or, in the case of spectral karyotyping, by using an interferometer attached to a fluorescence microscope.
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In the case of an mFISH image, every combination of fluorochromes from the resulting original images is replaced by a pseudo color in a dedicated image analysis software. Thus, chromosomes or chromosome sections can be visualized and identified, allowing for the analysis of chromosomal rearrangements. In the case of spectral karyotyping, image processing software assigns a pseudo color to each spectrally different combination, allowing the visualization of the individually colored chromosomes. Spectral human karyotype Multicolor FISH is used to identify structural chromosome aberrations in cancer cells and other disease conditions when Giemsa banding or other techniques are not accurate enough.
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Viewing anaglyphs through spectrally opposed glasses or gel filters enables each eye to see independent left and right images from within a single anaglyphic image. Red-cyan filters can be employed because our vision processing systems use red and cyan comparisons, as well as blue and yellow, to determine the color and contours of objects.Exercises in Three Dimensions: About 3D , Tom Lincoln, 2011 In a red-cyan anaglyph, the eye viewing through the red filter sees red within the anaglyph as "white", and the cyan within the anaglyph as "black". The eye viewing through the cyan filter perceives the opposite.
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If one or both of these end mirrors are replaced with a diffraction grating, the structure is then known as a DBR laser (Distributed Bragg Reflector). These longitudinal diffraction grating mirrors reflect the light back in the cavity, very much like a multi-layer mirror coating. The diffraction grating mirrors tend to reflect a narrower band of wavelengths than normal end mirrors, and this limits the number of standing waves that can be supported by the gain in the cavity. So DBR lasers tend to be more spectrally stable than Fabry-Perot lasers with broadband coatings.
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The white continuous light generated by the xenon arc is spectrally similar to daylight, but the lamp has a rather low efficacy in terms of lumens of visible light output per watt of input power. Today, almost all movie projectors in theaters employ these lamps, with power ratings ranging from 900 watts up to 12 kW. Omnimax (Imax Dome) projection systems use single xenon lamps with ratings as high as 15 kW. As of 2016, laser illumination for digital theater projectors is starting to establish a market presence and has been predicted to supersede the xenon arc lamp for this application.
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For example, 1970s 300 series cars and trucks sported a nostalgic looking somewhat art-deco-style blister card package with yellow at the bottom which changed upwards to orange, red and then purple. In the center of the package a downward pointing arrow design went rather spectrally from light green at the top to dark green and blue. Package backs featured fifteen illustrations (not photos) of other vehicles in the 300 series with their accompanying numbers. Each package was the same for each model, with little gold stickers on the plastic blisters labeling the number and type of vehicle (in French).
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Windowing of a simple waveform like causes its Fourier transform to develop non-zero values (commonly called spectral leakage) at frequencies other than ω. The leakage tends to be worst (highest) near ω and least at frequencies farthest from ω. If the waveform under analysis comprises two sinusoids of different frequencies, leakage can interfere with our ability to distinguish them spectrally. Possible types of interference are often broken down into two opposing classes as follows: If the component frequencies are dissimilar and one component is weaker, then leakage from the stronger component can obscure the weaker one's presence.
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Stewart measured radiated power with a thermo-pile and sensitive galvanometer read with a microscope. He was concerned with selective thermal radiation, which he investigated with plates of substances that radiated and absorbed selectively for different qualities of radiation rather than maximally for all qualities of radiation. He discussed the experiments in terms of rays which could be reflected and refracted, and which obeyed the Stokes-Helmholtz reciprocity principle (though he did not use an eponym for it). He did not in this paper mention that the qualities of the rays might be described by their wavelengths, nor did he use spectrally resolving apparatus such as prisms or diffraction gratings.
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The transmission method requires a weak broadband light source that spectrally covers the region of interest for the gain spectra. This light source is transmitted through the device of interest and the ratio of the intensities after and before the laser device provides the gain spectra. For this method, the device should operate on the fundamental lateral mode and the occurrence of Fabry–Pérot modes should be suppressed by deposition of at least one antireflection coating on the output facet of the device. In comparison to the stripe-length method and the Hakki–Paoli method, the transmission method provides the most accurate gain data for the widest range of injection currents.
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Multicolor imaging has been performed by using different activation wavelengths to distinguish dye-pairs, depending on the activator fluorophore used, or using spectrally distinct photoswitchable fluorophores, either with or without activator fluorophores. Photoswitchable fluorescent proteins can be used as well. Highly specific labeling of biological structures with photoswitchable probes has been achieved with antibody staining, direct conjugation of proteins, and genetic encoding. STORM has also been extended to three-dimensional imaging using optical astigmatism, in which the elliptical shape of the point spread function encodes the x, y, and z positions for samples up to several micrometers thick, and has been demonstrated in living cells.
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The most common use of preconditioning is for iterative solution of linear systems resulting from approximations of partial differential equations. The better the approximation quality, the larger the matrix size is. In such a case, the goal of optimal preconditioning is, on the one side, to make the spectral condition number of P^{-1}A to be bounded from above by a constant independent of the matrix size, which is called spectrally equivalent preconditioning by D'yakonov. On the other hand, the cost of application of the P^{-1} should ideally be proportional (also independent of the matrix size) to the cost of multiplication of A by a vector.
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On February 21, 2007, NASA and Nature released news that HD 209458 b was one of the first two extrasolar planets to have their spectra directly observed, the other one being HD 189733 b.NASA's Spitzer First To Crack Open Light of Faraway Worlds This was long seen as the first mechanism by which extrasolar but non-sentient life forms could be searched for, by way of influence on a planet's atmosphere. A group of investigators led by Jeremy Richardson of NASA's Goddard Space Flight Center spectrally measured HD 209458 b's atmosphere in the range of 7.5 to 13.2 micrometres. The results defied theoretical expectations in several ways.
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Most OEOs utilize the transmission characteristics of an optical modulator together with a fiber-optic delay line to convert light energy into stable, spectrally pure RF/microwave reference signals. Light from a laser is introduced into an electro-optic (E/O) modulator, the output of which is passed through a long optical fiber and detected with a photodetector. The output of the photodetector is amplified and filtered and fed back to the electric port of the modulator. This configuration supports self-sustained oscillations, at a frequency determined by the fiber delay length, the bias setting of the modulator, and the band pass characteristics of the filter.
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In addition to utilizing the dual- mode use of LEDs for communication, Mims decided to utilize the dual use of LEDs to perform measurements on specific properties of the atmosphere. In a paper published in Applied Optics (1992), entitled “Sun Photometer with light- emitting diodes as spectrally selective photodiodes”, Mims describes how LEDs can function as light detectors. In 2002, Mims followed with another LED sun photometer paper, “An inexpensive and stable LED Sun photometer for measuring the water vapor column over South Texas from 1990 to 2001”. In addition to his many electronics books written for Radio Shack, Mims developed several electronics kits for them.
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4709 Ennomos has an albedo slightly higher than the Jupiter-trojan average, which may indicate the presence of water ice. Some other Jupiter Trojans, such as 911 Agamemnon and 617 Patroclus, have shown very weak absorptions at 1.7 and 2.3 μm, which might indicate the presence of organics. The Jupiter trojans' spectra are similar to those of the irregular moons of Jupiter and, to a certain extent, comet nuclei, though Jupiter trojans are spectrally very different from the redder Kuiper belt objects. A Jupiter trojan's spectrum can be matched to a mixture of water ice, a large amount of carbon-rich material (charcoal), and possibly magnesium-rich silicates.
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Furthermore, spectrum sharing approaches between remote sensing and communications have traditionally been to separate or isolate both systems (temporally, spectrally or spatially). Hence, achieving RF convergence can be an incredibly complex and difficult problem to solve. Even for a simple network consisting of one remote sensing and communications system each, there are several independent factors in the time, space, and frequency domains that have to be taken into consideration in order to determine the optimal method to share spectral resources. For a given spectrum-space-time, a real network of systems will have many more sources or systems present, making the problem of achieving RF convergence even more complex.
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The algorithm that extracts the intensity and phase from the SI signal is direct. Spectral phase interferometry for direct electric- field reconstruction (SPIDER) is a nonlinear self-referencing technique based on spectral shearing interferometry. The method is similar to SI, except that the reference pulse is a spectrally shifted replica of itself, allowing one to obtain the spectral intensity and phase of the probe pulse via a direct FFT filtering routine similar to SI, but which requires integration of the phase extracted from the interferogram to obtain the probe pulse phase. Frequency- resolved optical gating (FROG) is a nonlinear technique that yields the intensity and phase of a pulse.
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This representation is approximately perpendicular to the axis of the tonotopic gradient, consistent with an orthogonal organization of spectral and temporal features in the auditory cortex. Combining these temporal responses with the spectral selectivity of A1 neurons gives rise to the spectro-temporal receptive fields that often capture well cortical responses to complex modulated sounds. In secondary auditory cortical fields, responses become temporally more sluggish and spectrally broader, but are still able to phase- lock to the salient features of speech and musical sounds. Tuning to AM rates below about 64 Hz is also found in the human auditory cortex as revealed by brain-imaging techniques (fMRI) and cortical recordings in epileptic patients (electrocorticography).
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Kantorovich in 1948 proposed calculating the smallest eigenvalue \lambda_1 of a symmetric matrix A by steepest descent using a direction r = Ax-\lambda (x) x of a scaled gradient of a Rayleigh quotient \lambda(x) = (x, Ax)/(x, x) in a scalar product (x, y) = x'y, with the step size computed by minimizing the Rayleigh quotient in the linear span of the vectors x and w, i.e. in a locally optimal manner. Samokish proposed applying a preconditioner T to the residual vector r to generate the preconditioned direction w = T r and derived asymptotic, as x approaches the eigenvector, convergence rate bounds. D'yakonov suggested spectrally equivalent preconditioning and derived non-asymptotic convergence rate bounds.
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A prototypical spatio-spectral scanning system, introduced in June 2014, consists of a basic slit spectroscope (slit + dispersive element) at some suitable, non-zero distance before a camera. (If the effective camera distance is zero, the system is applicable to spatial scanning). The imaging process is based on spectrally-decoded camera obscura projections: A series of projections from a continuous array of pinholes (= the slit) is projected onto the dispersive element, each projection contributing a rainbow-colored strip to the recorded two-dimensional image. The field of view in the wavelength- coded spatial dimension asymptotically approaches the dispersion angle of the dispersive element as the camera distance from the dispersive element approaches infinity.
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This alters the relative importance of different wavelengths in a spectral power distribution to each observer's color perception. As a result, two spectrally dissimilar lights or surfaces may produce a color match for one observer but fail to match when viewed by a second observer. Field-size metameric failure or field-size metamerism occurs because the relative proportions of the three cone types in the retina vary from the center of the visual field to the periphery, so that colors that match when viewed as very small, centrally fixated areas may appear different when presented as large color areas. In many industrial applications, large-field color matches are used to define color tolerances.
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This can enter buildings directly through windows or it can heat the building shell to a higher temperature than the ambient, increasing the heat transfer through the building envelope.Re- radiation of heat into the roof space during summer can cause sol-air temperatures to reach 60Co The Solar Heat Gain Co-efficient (SHGC)Windows Energy Ratings Scheme - WERS (a measure of solar heat transmittance) of standard single glazing can be around 78-85%. Solar gain can be reduced by adequate shading from the sun, light coloured roofing, spectrally selective (heat-reflective) paints and coatings and various types of insulation for the rest of the envelope. Specially coated glazing can reduce SHGC to around 10%.
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This cutoff frequency corresponds to a time constant of about 1 - 3 ms for the auditory system of normal-hearing humans. Correlated envelope fluctuations across frequency in a masker can aid detection of a pure tone signal, an effect known as comodulation masking release. AM applied to a given carrier can perceptually interfere with the detection of a target AM imposed on the same carrier, an effect termed modulation masking. Modulation-masking patterns are tuned (greater masking occurs for masking and target AMs close in modulation rate), suggesting that the human auditory system is equipped with frequency-selective channels for AM. Moreover, AM applied to spectrally remote carriers can perceptually interfere with the detection of AM on a target sound, an effect termed modulation detection interference.
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As a standard intended to satisfy needs of next-generation data networks (4G), WiMAX is distinguished by its dynamic burst algorithm modulation adaptive to the physical environment the RF signal travels through. Modulation is chosen to be more spectrally efficient (more bits per OFDM/SOFDMA symbol). That is, when the bursts have a high signal strength and a high carrier to noise plus interference ratio (CINR), they can be more easily decoded using digital signal processing (DSP). In contrast, operating in less favorable environments for RF communication, the system automatically steps down to a more robust mode (burst profile) which means fewer bits per OFDM/SOFDMA symbol; with the advantage that power per bit is higher and therefore simpler accurate signal processing can be performed.
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Iwabuchi [2003] employed a method to calibrate NOAA-11 and -14 that uses clear-sky ocean and stratus cloud reflectance observations in a region of the NW Pacific Ocean and radiative transfer calculations of a theoretical molecular atmosphere to calibrate AVHRR Ch. 1. Using a month of clear-sky observations over the ocean, an initial minimum guess to the calibration slope is made. An iterative method is then used to achieve the optimal slope values for Ch. 1 with slope corrections adjusting for uncertainties in ocean reflectance, water vapor, ozone, and noise. Ch. 2 is then subsequently calibrated under the condition that the stratus cloud optical thickness in both channels must be the same (spectrally uniform in the visible) if their calibrations are correct [Iwabuchi, 2003].
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The RF bandwidth of an AM transmission (refer to Figure 2, but only considering positive frequencies) is twice the bandwidth of the modulating (or "baseband") signal, since the upper and lower sidebands around the carrier frequency each have a bandwidth as wide as the highest modulating frequency. Although the bandwidth of an AM signal is narrower than one using frequency modulation (FM), it is twice as wide as single-sideband techniques; it thus may be viewed as spectrally inefficient. Within a frequency band, only half as many transmissions (or "channels") can thus be accommodated. For this reason analog television employs a variant of single-sideband (known as vestigial sideband, somewhat of a compromise in terms of bandwidth) in order to reduce the required channel spacing.
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An exhumed crater apron nearly to the east of the mesa appears to cross-cut a structure that has been interpreted by some researchers to be a now-buried part of the mesa. Large-scale mass wasting of these weaker stratigraphic units (most notably, in the landslide of two blocks down the southern face of the mesa) has been conspicuously observed on the mesa. The observed layers described above—termed interior layered deposits by researchers—are of considerable interest to researchers studying the possibility of past life on Mars due to the spectrally-inferred presence of kieserite, a polyhydrated magnesium sulfate mineral. Such a mineral only forms in sufficient quantities in acidic aqueous environments, suggesting the longstanding presence of water in areas where these materials are found.
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Image shift due to defocus depends on wavelength. The angular dependence of multilayer reflectance of the object (mask) is different for different wavelengths, leading to different shifts when defocused. Unlike DUV lithography sources, based on excimer lasers, EUV plasma sources produce light across a broad range of wavelengths. Though the EUV spectrum is not completely monochromatic, nor even as spectrally pure as DUV laser sources, the working wavelength has generally been taken to be 13.5 nm. In actuality, the reflected power is distributed mostly in the 13.3-13.7 nm range. The bandwidth of EUV light reflected by a multilayer mirror used for EUV lithography is over +/-2% (>270 pm); the phase changes due to wavelength changes at a given illumination angle may be calculated and compared to the aberration budget.Y. Nakajima et al.
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Alice ultraviolet imaging spectrometer on New Horizons An imaging spectrometer is an instrument used in hyperspectral imaging and imaging spectroscopy to acquire a spectrally-resolved image of an object or scene, often referred to as a datacube due to the three-dimensional representation of the data. Two axes of the image corresponds to vertical and horizontal distance and the third to wavelength. The principle of operation is the same as that of the simple spectrometer, but special care is taken to avoid optical aberrations for better image quality. Example imaging spectrometer types include: filtered camera, whiskbroom scanner, pushbroom scanner, integral field spectrograph (or related dimensional reformatting techniques), wedge imaging spectrometer, Fourier transform imaging spectrometer, computed tomography imaging spectrometer (CTIS), image replicating imaging spectrometer (IRIS), coded aperture snapshot spectral imager (CASSI), and image mapping spectrometer (IMS).
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In addition to its current use in submillimetre astronomy, terahertz radiation spectroscopy could provide new sources of information for chemistry and biochemistry. Recently developed methods of THz time-domain spectroscopy (THz TDS) and THz tomography have been shown to be able to image samples that are opaque in the visible and near-infrared regions of the spectrum. The utility of THz-TDS is limited when the sample is very thin, or has a low absorbance, since it is very difficult to distinguish changes in the THz pulse caused by the sample from those caused by long-term fluctuations in the driving laser source or experiment. However, THz-TDS produces radiation that is both coherent and spectrally broad, so such images can contain far more information than a conventional image formed with a single-frequency source.
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It uses a GPS and Augmented Reality (AR) technology in conjunction with camera to create a live video stream with a more comprehensive visual display of the targets. The SIRE radar is part of a long generation of UWB and synthetic aperture radar (SAR) systems developed by the U.S. Army Research Laboratory (ARL) starting in the early 1990s. Past systems include the railSAR and the boomSAR systems as well as the more recent Spectrally Agile Frequency- Incrementing Reconfigurable (SAFIRE) radar system. The SIRE radar was eventually transitioned to the Communications Electronics Research, Development and Engineering Center (CERDEC) at Fort Belvoir, VA. There, it was redesigned as the ALARIC radar system, which was modified to have one fewer transmitter and operate at a bandwidth range from 100 MHz to 1.5 GHz.
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Multiuser detection deals with demodulation of the mutually interfering digital streams of information that occur in areas such as wireless communications, high-speed data transmission, DSL, satellite communication, digital television, and magnetic recording.Sergio Verdu, "Multiuser Detection", Cambridge University Press, 1998, It is also being currently investigated for demodulation in low-power inter-chip and intra-chip communication. Multiuser detection encompasses both receiver technologies devoted to joint detection of all the interfering signals or to single-user receivers which are interested in recovering only one user but are robustified against multiuser interference and not just background noise. Mutual interference is unavoidable in modern spectrally efficient wireless systems: even when using orthogonal multiplexing systems such as TDMA, synchronous CDMA or OFDMA, multiuser interference originates from channel distortion and from out-of-cell interference.
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A typical glossmeter consists of a fixed mechanical assembly comprising a standardised light source that projects a parallel beam of light onto the test surface to be measured and a filtered detector located to receive the rays reflected from the surface. The ASTM Method states that the illumination should be defined such that the source- detector combination is spectrally corrected to give the CIE luminous efficiency, V(?), with CIE illuminant SC.CIE Publication No. 15.2, Colorimetry, Vienna, 1986 A parallel-beam specular reflection instrument A number of instruments are commercially available that conform to the above standards in terms of their measurement geometry. The instruments are calibrated using reference standards that are usually made from highly polished, plane, black glass with a refractive index of 1.567 for the Sodium D line, and these are assigned a gloss value of 100 for each geometry.
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The radiation can also be spectrally resolved with the time-stretch dispersive Fourier transform (TS-DFT), which produces a wavelength-to-time mapping such that the temporal traces collected for each event correspond to the actual spectral profile over the filtered bandwidth. The TS-DFT has subsequently been used to stretch the complete (unfiltered) output spectra of such broadband pulses, thereby allowing measurement of full pulse-resolved spectra at the megahertz repetition rate of the source (see below). Pulse-resolved measurements showed that a fraction of the pulses had much more redshifted energy content than the majority of events. In other words, the energy passed by the filter was much larger for a small fraction of the events, and the fraction of events with anomalous energy content in this spectral band could be increased by raising the power of the input pulses.
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As with any small signal amplification, it is most desirable to get gain as close as possible to the initial point of the signal interception: moving the gain ahead of any signal processing reduces the additive contributions of effects like resistor Johnson–Nyquist noise, or electrical noises in active circuits. In optical heterodyne detection, the mixing-gain happens directly in the physics of the initial photon absorption event, making this ideal. Additionally, to a first approximation, absorption is perfectly quadratic, in contrast to RF detection by a diode non-linearity. One of the virtues of heterodyne detection is that the difference frequency is generally far removed spectrally from the potential noises radiated during the process of generating either the signal or the LO signal, thus the spectral region near the difference frequency may be relatively quiet.
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Several types of fibers have been successfully tested : non-zero dispersion-shifted fibers, highly nonlinear silica fibers (HNLF), microstructured silica fibers, chalcogenide fibers or tellurite fibers. At the fiber output, an optical bandpass filter (OBPF) with a FWHM spectral width \delta f, (defined such that the pulse width at the output is the same as that at the input of the system), is spectrally offset by an amount \Delta \lambda with respect to the input signal carrier wavelength \lambda_0 and is used to carve into the broadened spectrum - thereby acting as a pulse reshaper. Experimental setup used for the Mamyshev regenerator This is the unit configuration, which may be repeated for higher accuracy of the regeneration. It has been shown possible to advantageously replace the nonlinear fiber by a highly-nonlinear chalcogenide waveguide, therefore opening the way to all-integrated photonic chip regeneration.
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In addition to that, the cones at the bird's retina are arranged in a characteristic form of spatial distribution, known as hyperuniform distribution, which maximizes its light and color absorption. This form of spatial distributions are only observed as a result of some optimization process, which in this case can be described in terms of birds’ evolutionary history. The four spectrally distinct cone pigments are derived from the protein opsin, linked to a small molecule called retinal, which is closely related to vitamin A. When the pigment absorbs light the retinal changes shape and alters the membrane potential of the cone cell affecting neurons in the ganglia layer of the retina. Each neuron in the ganglion layer may process information from a number of photoreceptor cells, and may in turn trigger a nerve impulse to relay information along the optic nerve for further processing in specialised visual centres in the brain.
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The Journal of Adhesion, v80, Issue 1 & 2, p 37 - 59, There are two main types of sum frequency spectrometer, scanning systems and broadband systems. For the former type of spectrometer, one of the beams is a visible wavelength laser held at a constant frequency and the other is a tunable infrared laser — by tuning the IR laser, the system can scan over resonances and obtain the vibrational spectrum of the interfacial region in a piecewise fashion. In the case of broadband spectrometers, one laser (typically the visible laser) is kept at a fixed narrow wavelength, and the other laser produces a spectrally broad beam. These laser beams again overlap at the interface being studied, but can cover a wider range of resonances at once than a spectrometer operating in scanning mode and hence spectra can be acquired much faster, allowing the ability to perform time-resolved measurements with interfacial sensitivity.
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An off-the-shelf digital camera contains an infrared hot mirror filter that blocks most of the infrared and a bit of the ultraviolet that would otherwise be detected by the sensor, narrowing the accepted range from about 400 nm to 700 nm. Replacing a hot mirror or infrared blocking filter with an infrared pass or a wide spectrally transmitting filter allows the camera to detect the wider spectrum light at greater sensitivity. Without the hot-mirror, the red, green and blue (or cyan, yellow and magenta) elements of the color filter array placed over the sensor elements pass varying amounts of ultraviolet and infrared which may be recorded in any of the red, green or blue channels depending on the particular sensor in use and on the dyes used in the Bayer filter. A converted full-spectrum camera can be used for ultraviolet photography or infrared photography with the appropriate filters.
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In September 2001, there was speculation that Tagish Lake meteorite which struck in British Columbia, Canada on January 18, 2000, was derived from a D-type asteroid, since the spectral shape and brightness of the meteorite was similar to D-type asteroids. Of the three studied, the 0.032 IRAS albedos (8) of 368 Haidea and the 0.033 IRAS albedos (8) of 773 Irmintraud are both considered close to the reflectance of the Tagish Lake meteorite. Moreover, even though 368 Haidea was closest spectrally to the Tagish Lake meteorite, 773 Irmintraud was no more than 0.034 AU to a chaotic zone associated with one of the Kirkwood gaps due to the mean motion resonance with Jupiter. This made 773 Irmintraud the closest of the three candidates to the associated chaotic zone and thus the most likely of the three as the source of the 2000 Earth impacted meteorite. The idea that humans held a piece of the asteroid 773 Irmintraud spurred others to act.
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