1.
Military colours, standards and guidons
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The Roman Empire also made battle standards a part of their vast armies. It was formalized in the armies of Europe in the High Middle Ages, as armies became trained and adopted set formations, each regiments ability to keep its formation was potentially critical to its, and therefore its armys, success. In the chaos of battle, not least due to the amount of dust and smoke on a battlefield, Regimental flags are generally awarded to a regiment by a head-of-State during a ceremony. They were therefore treated with reverence as they represented the honour, Colours may be inscribed with the names of battles or other symbols representing former achievements. Regiments tended to adopt colour guards, composed of experienced or élite soldiers, as a result, the capture of an enemys standard was considered as a great feat of arms. They are never capriciously destroyed – when too old to use they are replaced and then laid-up in museums, religious buildings and other places of significance to their regiment. However, in most modern armies, standing orders now call for the Colours to be destroyed if they are ever in jeopardy of being captured by the enemy. Due to the advent of modern weapons, and subsequent changes in tactics, Colours are no longer carried into battle, but continue to be used at events of formal character. The Armed Forces of the Argentine Republics military Colours of the Argentine Army, Argentine Navy and Argentine Air Force are the Flag of Argentina as the National War Colour and the Unit Colour. The National War Colour is a variation of the Argentine national flag made for use, while the Unit Colour differs per service arm. Only the Regiment of Patricians uses company colors, cadet squadron colours are used by the Argentine Air Force Academy. Units of the Brazilian Armed Forces carry a stand of two Colours, differing per service, the standard of the Army measures 80 ×120 cm, white with the Army coat of arms in the centre, trimmed with gold fringe. The name of the service is inscribed in letters on a green scroll beneath the shield. Above the shield is a helmet with red and sky blue mantling. The staff is topped by a nickel-plated lance-head finial,32 cm high, ten red streamers with campaign honours inscribed in sky blue letters are also attached below the lance-head. The staff is 212 cm long, not including the lance-head and it is covered in sky blue velvet with a red spiral strip. The colour belt is 10 cm in width, covered with sky blue velvet with red velvet stripes, the Navys flag uses dark blue colours, the Air Force flag ultramarine blue. Brazilian military units also carry the flag as a National Colour
2.
False flag
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While Kormoran was fatally damaged in the engagement and its crew captured the outcome represented a considerable psychological victory for the Germans. In December 1922–February 1923, Rules concerning the Control of Wireless Telegraphy in Time of War and Air Warfare, drafted by a commission of jurists at the Hague regulates, a military aircraft must carry an exterior mark indicating its nationality and its military character. The use of false exterior marks is forbidden, during the trial, a number of arguments were advanced to substantiate this position and the German and U. S. military seem to have been in agreement. The foregoing rule, does not prohibit such use, but does prohibit their improper use and it is certainly forbidden to make use of them during a combat. Before opening fire upon the enemy, they must be discarded, the American Soldiers Handbook was also quoted by Defense Counsel, The use of the enemy flag, insignia, and uniform is permitted under some circumstances. They are not to be used during fighting, and if used in order to approach the enemy without drawing fire. Subsequently, the outcome of the trial has been codified in the 1977 Protocol Additional to the Geneva Conventions of 12 August 1949 and it is prohibited to kill, injure, or capture an adversary by resort to perfidy. Ruses of war are not prohibited, the following are examples of such ruses, the use of camouflage, decoys, mock operations and disinformation. It is prohibited to use of the distinctive emblem of the United Nations. It is prohibited to use in an armed conflict of the flags or military emblems. It is prohibited to use of the flags or military emblems, insignia or uniforms of adverse Parties while engaging in attacks or in order to shield, favour. A false flag in the domain is slightly different and easier to perpetrate than in other physical theaters of war. This misdirection tactic can cause misattribution or misperception which can lead to retaliation against the wrong adversary, in 1788, the head tailor at the Royal Swedish Opera received an order to sew a number of Russian military uniforms. These were then used by the Swedes to stage an attack on Puumala and this caused an outrage in Stockholm and impressed the Riksdag of the Estates, the Swedish national assembly, who until then had refused to agree to an offensive war against Russia. The Puumala incident allowed King Gustav III of Sweden, who lacked the authority to initiate unprovoked hostilities without the Estates consent. In September 1931, Japanese officers fabricated a pretext for invading Manchuria by blowing up a section of railway, the Gleiwitz incident in 1939 involved Reinhard Heydrich fabricating evidence of a Polish attack against Germany to mobilize German public opinion for war and to justify the war with Poland. Alfred Naujocks was a key organiser of the operation orders from Heydrich. It led to the deaths of Nazi concentration camp victims who were dressed as German soldiers and this, along with other false flag operations in Operation Himmler, would be used to mobilize support from the German population for the start of World War II in Europe
3.
Optical filter
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Filters mostly belong to one of two categories. The simplest, physically, is the filter, then there are interference or dichroic filters. Optical filters selectively transmit light in a range of wavelengths. They can usually pass long wavelengths only, short wavelengths only, or a band of wavelengths, the passband may be narrower or wider, the transition or cutoff between maximal and minimal transmission can be sharp or gradual. Optical filters are used in photography, in many optical instruments. Optical filters are essential in fluorescence applications such as fluorescence microscopy. Photographic filters are a case of optical filters, and much of the material here applies. Some photographic effect filters, such as star effect filters, are not relevant to scientific work, absorptive filters are usually made from glass to which various inorganic or organic compounds have been added. These compounds absorb some wavelengths of light while transmitting others, the compounds can also be added to plastic to produce gel filters, which are lighter and cheaper than glass-based filters. Alternately, dichroic filters can be made by coating a substrate with a series of optical coatings. Dichroic filters usually reflect the unwanted portion of the light and transmit the remainder, Dichroic filters use the principle of interference. Their layers form a series of reflective cavities that resonate with the desired wavelengths. Other wavelengths destructively cancel or reflect as the peaks and troughs of the waves overlap, Dichroic filters are particularly suited for precise scientific work, since their exact colour range can be controlled by the thickness and sequence of the coatings. They are usually more expensive and delicate than absorption filters. They can be used in such as the dichroic prism of a camera to separate a beam of light into different coloured components. The basic scientific instrument of this type is a Fabry–Pérot interferometer and it uses two mirrors to establish a resonating cavity. It passes wavelengths that are a multiple of the resonance frequency. Etalons are another variation, transparent cubes or fibers whose polished ends form mirrors tuned to resonate with specific wavelengths and these are often used to separate channels in telecommunications networks that use wavelength division multiplexing on long-haul optic fibers
4.
Moon
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The Moon is an astronomical body that orbits planet Earth, being Earths only permanent natural satellite. It is the fifth-largest natural satellite in the Solar System, following Jupiters satellite Io, the Moon is second-densest satellite among those whose densities are known. The average distance of the Moon from the Earth is 384,400 km, the Moon is thought to have formed about 4.51 billion years ago, not long after Earth. It is the second-brightest regularly visible celestial object in Earths sky, after the Sun and its surface is actually dark, although compared to the night sky it appears very bright, with a reflectance just slightly higher than that of worn asphalt. Its prominence in the sky and its cycle of phases have made the Moon an important cultural influence since ancient times on language, calendars, art. The Moons gravitational influence produces the ocean tides, body tides, and this matching of apparent visual size will not continue in the far future. The Moons linear distance from Earth is currently increasing at a rate of 3.82 ±0.07 centimetres per year, since the Apollo 17 mission in 1972, the Moon has been visited only by uncrewed spacecraft. The usual English proper name for Earths natural satellite is the Moon, the noun moon is derived from moone, which developed from mone, which is derived from Old English mōna, which ultimately stems from Proto-Germanic *mǣnōn, like all Germanic language cognates. Occasionally, the name Luna is used, in literature, especially science fiction, Luna is used to distinguish it from other moons, while in poetry, the name has been used to denote personification of our moon. The principal modern English adjective pertaining to the Moon is lunar, a less common adjective is selenic, derived from the Ancient Greek Selene, from which is derived the prefix seleno-. Both the Greek Selene and the Roman goddess Diana were alternatively called Cynthia, the names Luna, Cynthia, and Selene are reflected in terminology for lunar orbits in words such as apolune, pericynthion, and selenocentric. The name Diana is connected to dies meaning day, several mechanisms have been proposed for the Moons formation 4.51 billion years ago, and some 60 million years after the origin of the Solar System. These hypotheses also cannot account for the angular momentum of the Earth–Moon system. This hypothesis, although not perfect, perhaps best explains the evidence, eighteen months prior to an October 1984 conference on lunar origins, Bill Hartmann, Roger Phillips, and Jeff Taylor challenged fellow lunar scientists, You have eighteen months. Go back to your Apollo data, go back to computer, do whatever you have to. Dont come to our conference unless you have something to say about the Moons birth, at the 1984 conference at Kona, Hawaii, the giant impact hypothesis emerged as the most popular. Afterward there were only two groups, the giant impact camp and the agnostics. Giant impacts are thought to have been common in the early Solar System, computer simulations of a giant impact have produced results that are consistent with the mass of the lunar core and the present angular momentum of the Earth–Moon system
5.
Color
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Color or colour is the characteristic of human visual perception described through color categories, with names such as red, yellow, purple, or blue. This perception of color derives from the stimulation of cells in the human eye by electromagnetic radiation in the spectrum of light. Color categories and physical specifications of color are associated with objects through the wavelength of the light that is reflected from them and this reflection is governed by the objects physical properties such as light absorption, emission spectra, etc. By defining a color space, colors can be identified numerically by coordinates, there may also be more than three color dimensions in other color spaces, such as in the CMYK color model, wherein one of the dimensions relates to a colours colorfulness). The photo-receptivity of the eyes of species also varies considerably from our own. Honeybees and bumblebees for instance have trichromatic color vision sensitive to ultraviolet but is insensitive to red, papilio butterflies possess six types of photoreceptors and may have pentachromatic vision. The most complex color vision system in the kingdom has been found in stomatopods with up to 12 spectral receptor types thought to work as multiple dichromatic units. The science of color is sometimes called chromatics, colorimetry, or simply color science and it includes the perception of color by the human eye and brain, the origin of color in materials, color theory in art, and the physics of electromagnetic radiation in the visible range. Electromagnetic radiation is characterized by its wavelength and its intensity, when the wavelength is within the visible spectrum, it is known as visible light. Most light sources emit light at different wavelengths, a sources spectrum is a distribution giving its intensity at each wavelength. Although the spectrum of light arriving at the eye from a given direction determines the color sensation in that direction, in each such class the members are called metamers of the color in question. The table at right shows approximate frequencies and wavelengths for various pure spectral colors, the wavelengths listed are as measured in air or vacuum. A common list identifies six main bands, red, orange, yellow, green, blue, Newtons conception included a seventh color, indigo, between blue and violet. It is possible that what Newton referred to as blue is nearer to what today is known as cyan, the color of an object depends on both the physics of the object in its environment and the characteristics of the perceiving eye and brain. Some objects not only light, but also transmit light or emit light themselves. This effect is known as color constancy, opaque objects that do not reflect specularly have their color determined by which wavelengths of light they scatter strongly. If objects scatter all wavelengths with roughly equal strength, they appear white, if they absorb all wavelengths, they appear black. Opaque objects that reflect light of different wavelengths with different efficiencies look like mirrors tinted with colors determined by those differences
6.
Signal processing
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According to Alan V. Oppenheim and Ronald W. Schafer, the principles of signal processing can be found in the classical numerical analysis techniques of the 17th century. Oppenheim and Schafer further state that the digitalization or digital refinement of techniques can be found in the digital control systems of the 1940s and 1950s. Feature extraction, such as understanding and speech recognition. Quality improvement, such as reduction, image enhancement. Including audio compression, image compression, and video compression and this involves linear electronic circuits as well as non-linear ones. The former are, for instance, passive filters, active filters, additive mixers, integrators, non-linear circuits include compandors, multiplicators, voltage-controlled filters, voltage-controlled oscillators and phase-locked loops. Continuous-time signal processing is for signals that vary with the change of continuous domain, the methods of signal processing include time domain, frequency domain, and complex frequency domain. This technology was a predecessor of digital processing, and is still used in advanced processing of gigahertz signals. Digital signal processing is the processing of digitized discrete-time sampled signals, processing is done by general-purpose computers or by digital circuits such as ASICs, field-programmable gate arrays or specialized digital signal processors. Typical arithmetical operations include fixed-point and floating-point, real-valued and complex-valued, other typical operations supported by the hardware are circular buffers and look-up tables. Examples of algorithms are the Fast Fourier transform, finite impulse response filter, Infinite impulse response filter, nonlinear signal processing involves the analysis and processing of signals produced from nonlinear systems and can be in the time, frequency, or spatio-temporal domains. Nonlinear systems can produce complex behaviors including bifurcations, chaos, harmonics
7.
Visible spectrum
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The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm, in terms of frequency, this corresponds to a band in the vicinity of 430–770 THz. The spectrum does not, however, contain all the colors that the human eyes, unsaturated colors such as pink, or purple variations such as magenta, are absent, for example, because they can be made only by a mix of multiple wavelengths. Colors containing only one wavelength are called pure colors or spectral colors. Visible wavelengths pass through the window, the region of the electromagnetic spectrum that allows wavelengths to pass largely unattenuated through the Earths atmosphere. An example of this phenomenon is that clean air scatters blue light more than red wavelengths, the optical window is also referred to as the visible window because it overlaps the human visible response spectrum. The near infrared window lies just out of the vision, as well as the Medium Wavelength IR window. In the 13th century, Roger Bacon theorized that rainbows were produced by a process to the passage of light through glass or crystal. In the 17th century, Isaac Newton discovered that prisms could disassemble and reassemble white light and he was the first to use the word spectrum in this sense in print in 1671 in describing his experiments in optics. The result is red light is bent less sharply than violet as it passes through the prism. Newton divided the spectrum into seven named colors, red, orange, yellow, green, blue, indigo, the human eye is relatively insensitive to indigos frequencies, and some people who have otherwise-good vision cannot distinguish indigo from blue and violet. For this reason, some commentators, including Isaac Asimov, have suggested that indigo should not be regarded as a color in its own right. However, the evidence indicates that what Newton meant by indigo, comparing Newtons observation of prismatic colors to a color image of the visible light spectrum shows that indigo corresponds to what is today called blue, whereas blue corresponds to cyan. In the 18th century, Goethe wrote about optical spectra in his Theory of Colours, Goethe used the word spectrum to designate a ghostly optical afterimage, as did Schopenhauer in On Vision and Colors. Goethe argued that the spectrum was a compound phenomenon. Where Newton narrowed the beam of light to isolate the phenomenon, Goethe observed that a wider aperture produces not a spectrum but rather reddish-yellow, the spectrum appears only when these edges are close enough to overlap. Young was the first to measure the wavelengths of different colors of light, the connection between the visible spectrum and color vision was explored by Thomas Young and Hermann von Helmholtz in the early 19th century
8.
Electromagnetic spectrum
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The electromagnetic spectrum is the collective term for all known frequencies and their linked wavelengths of the known photons. The electromagnetic spectrum of an object has a different meaning, and is instead the characteristic distribution of radiation emitted or absorbed by that particular object. Visible light lies toward the end, with wavelengths from 400 to 700 nanometres. The limit for long wavelengths is the size of the universe itself, until the middle of the 20th century it was believed by most physicists that this spectrum was infinite and continuous. Nearly all types of radiation can be used for spectroscopy, to study. Other technological uses are described under electromagnetic radiation, for most of history, visible light was the only known part of the electromagnetic spectrum. The ancient Greeks recognized that light traveled in straight lines and studied some of its properties, the study of light continued, and during the 16th and 17th centuries conflicting theories regarded light as either a wave or a particle. The first discovery of electromagnetic radiation other than visible light came in 1800 and he was studying the temperature of different colors by moving a thermometer through light split by a prism. He noticed that the highest temperature was beyond red and he theorized that this temperature change was due to calorific rays that were a type of light ray that could not be seen. The next year, Johann Ritter, working at the end of the spectrum. These behaved similarly to visible light rays, but were beyond them in the spectrum. They were later renamed ultraviolet radiation, during the 1860s James Maxwell developed four partial differential equations for the electromagnetic field. Two of these equations predicted the possibility of, and behavior of, analyzing the speed of these theoretical waves, Maxwell realized that they must travel at a speed that was about the known speed of light. This startling coincidence in value led Maxwell to make the inference that light itself is a type of electromagnetic wave, maxwells equations predicted an infinite number of frequencies of electromagnetic waves, all traveling at the speed of light. This was the first indication of the existence of the electromagnetic spectrum. Maxwells predicted waves included waves at very low compared to infrared. Hertz found the waves and was able to infer that they traveled at the speed of light, Hertz also demonstrated that the new radiation could be both reflected and refracted by various dielectric media, in the same manner as light. For example, Hertz was able to focus the waves using a lens made of tree resin, in a later experiment, Hertz similarly produced and measured the properties of microwaves
9.
Photograph
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A photograph or photo is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic medium such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scenes visible wavelengths of light into a reproduction of what the eye would see. The process and practice of creating photographs is called photography, the word photograph was coined in 1839 by Sir John Herschel and is based on the Greek φῶς, meaning light, and γραφή, meaning drawing, writing, together meaning drawing with light. The first permanent photograph, a copy of an engraving, was made in 1822 using the bitumen-based heliography process developed by Nicéphore Niépce. In 1829 Niépce entered into a partnership with Louis Daguerre and the two collaborated to work out a similar but more sensitive and otherwise improved process, after Niépces death in 1833, Daguerre concentrated on silver halide-based alternatives. He named this first practical process for making photographs with a camera the daguerreotype and its existence was announced to the world on 7 January 1839 but working details were not made public until 19 August. Other inventors soon made improvements which reduced the exposure time from a few minutes to a few seconds, making portrait photography truly practical. The daguerreotype had shortcomings, notably the fragility of the image surface. Each was a unique opaque positive that could only be duplicated by copying it with a camera, inventors set about working out improved processes that would be more practical. By the end of the 1850s the daguerreotype had been replaced by the expensive and more easily viewed ambrotype and tintype. The mid-1930s saw the introduction of Kodachrome and Agfacolor Neu, the first easy-to-use color films of the modern multi-layer chromogenic type, the needs of the motion picture industry generated a number of special processes and systems, perhaps the best-known being the now-obsolete three-strip Technicolor process. Non-digital photographs are produced with a chemical process. In the two-step process the film captures a negative image. To produce an image, the negative is most commonly transferred onto photographic paper. Printing the negative onto transparent film stock is used to motion picture films. Alternatively, the film is processed to invert the negative image, such positive images are usually mounted in frames, called slides. Before recent advances in photography, transparencies were widely used by professionals because of their sharpness. Most photographs published in magazines were taken on color transparency film, originally, all photographs were monochromatic or hand-painted in color
10.
Information visualization
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Information visualization or information visualisation is the study of visual representations of abstract data to reinforce human cognition. The abstract data include both numerical and non-numerical data, such as text and geographic information, however, information visualization differs from scientific visualization, it’s infovis when the spatial representation is chosen, and it’s scivis when the spatial representation is given. The field of visualization has emerged from research in human-computer interaction, computer science, graphics, visual design, psychology. Information visualization focused on the creation of approaches for conveying information in intuitive ways. Data analysis is an part of all applied research and problem solving in industry. The most fundamental data analysis approaches are visualization, statistics, data mining, the analyst does not have to learn any sophisticated methods to be able to interpret the visualizations of the data. Information visualization is also a hypothesis generation scheme, which can be, the modern study of visualization started with computer graphics, which has from its beginning been used to study scientific problems. However, in its early days the lack of power often limited its usefulness. The recent emphasis on visualization started in 1987 with the issue of Computer Graphics on Visualization in Scientific Computing. Since then there have been several conferences and workshops, co-sponsored by the IEEE Computer Society and they have been devoted to the general topics of data visualisation, information visualization and scientific visualisation, and more specific areas such as volume visualization. In 1786, William Playfair published the first presentation graphics, the Craft of Information Visualization, Readings and Reflections. Stuart K. Card, Jock D. Mackinlay and Ben Shneiderman, Readings in Information Visualization, Using Vision to Think, Morgan Kaufmann Publishers. Jeffrey Heer, Stuart K. Card, James Landay, prefuse, a toolkit for interactive information visualization. In, ACM Human Factors in Computing Systems CHI2005, andreas Kerren, John T. Stasko, Jean-Daniel Fekete, and Chris North. Information Visualization – Human-Centered Issues and Perspectives, volume 4950 of LNCS State-of-the-Art Survey, Springer. Spence, Robert Information Visualization, Design for Interaction, Prentice Hall,2007, ISBN 0-13-206550-9
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