Definitions.

Light pollution is the presence of artificial light in otherwise dark conditions. The term is most commonly used in relation to in the outdoor environment, but is also used to refer to artificial light indoors. Adverse consequences are multiple; some of them may not be known yet. Light pollution competes with starlight in the night sky for urban residents, interferes with astronomical observatories, and, like any other form of pollution, disrupts ecosystems and has adverse health effects.  Light pollution is a side-effect

Impact on energy usage.

Energy conservation advocates contend that light pollution must be addressed by changing the habits of society, so that lighting is used more efficiently, with less waste and less creation of unwanted or unneeded illumination. Several industry groups also recognize light pollution as an important issue. For example, the Institution of Lighting Engineers in the United Kingdom provides its members with information about light pollution, the problems it causes, and how to reduce its impact. Although, recent research point that the energy efficiency is not enough to reduce the light pollution because of the rebound effect.  Since not everyone is irritated by the same lighting sources, it is common for one person's

Types.

Light pollution is caused by inefficient or unnecessary use of artificial light. Specific categories of light pollution include light trespass, over-illumination, glare, light clutter, and skyglow. A single offending light source often falls into more than one of these categories.

Light trespass.

Light trespass occurs when unwanted light enters one's property, for instance, by shining over a neighbor's fence. A common light trespass problem occurs when a strong light enters the window of one's home from the outside, causing problems such as sleep deprivation. A number of cities in the U.S. have developed standards for outdoor lighting to protect the rights of their citizens against light trespass. To assist them, the International Dark-Sky Association has developed a set of model lighting ordinances.  The Dark-Sky Association was started to reduce the light going up into the sky which reduces visibility of stars (see Skyglow below). This is any light which is emitted more than 90° above

Over-illumination.

Over-illumination is the excessive use of light. Specifically within the United States, over-illumination is responsible for approximately two million barrels of oil per day in energy wasted. This is based upon U.S. consumption of equivalent of of petroleum. It is further noted in the same U.S. Department of Energy (DOE) source that over 30% of all primary energy is consumed by commercial, industrial and residential sectors. Energy audits of existing buildings demonstrate that the lighting component of residential, commercial and industrial uses consumes about 20–40% of those land uses, variable with region and land use. (Residential use lighting consumes only 10–30% of the energy bill while commercial buildings' major use is lighting.) Thus lighting energy accounts for about four or five million barrels of oil (equivalent) per day. Again energy audit data demonstrates that about 30–60% of energy consumed in lighting is unneeded or

Glare.

Glare can be categorized into different types. One such classification is described in a book by Bob Mizon, coordinator for the British Astronomical Association's Campaign for Dark Skies, as follows:  According to Mario Motta, president of the Massachusetts Medical Society, "...glare from bad lighting is a public-health hazard—especially the older you become. Glare light scattering in the eye causes loss of contrast and leads to unsafe driving conditions, much like the glare on a dirty

Light clutter.

Light clutter refers to excessive groupings of lights. Groupings of lights may generate confusion, distract from obstacles (including those that they may be intended to illuminate), and potentially cause accidents. Clutter is

From satellites.

Another source of light pollution are artificial satellites. With future increase in numbers of satellite constellations, like OneWeb

Measurement and global effects.

Measuring the effect of sky glow on a global scale is a complex procedure. The natural atmosphere is not completely dark, even in the absence of terrestrial sources of light and illumination from the Moon. This is caused by two main sources: "airglow" and "scattered light".  At high altitudes, primarily above the mesosphere, there is enough UV radiation from the sun of very short wavelength to cause ionization. When the ions collide with electrically neutral particles they recombine and emit photons in the process, causing airglow. The degree of ionization is sufficiently large to allow a constant emission of radiation even during the night when the upper atmosphere is in the Earth's shadow. Lower in the atmosphere all the solar photons with energies above the ionization potential of N and O have already been absorbed by the higher layers and thus no appreciable ionization occurs.  Apart from emitting light, the sky also scatters incoming light, primarily from distant stars and the Milky Way, but also the zodiacal light, sunlight that is reflected and backscattered from interplanetary dust particles.  The amount of airglow and zodiacal light is quite variable (depending, amongst other things on sunspot activity and the Solar cycle) but given optimal conditions the darkest possible sky has a brightness of about 22 magnitude/square arc second. If a full moon is present, the sky brightness increases to about 18 magnitude/sq. arc second depending on local atmospheric transparency, 40 times brighter than the darkest sky. In densely populated areas a sky brightness of 17 magnitude/sq. arc second

Consequences.

Effects on human health and psychology.

Medical research on the effects of excessive light on the human body suggests that a variety of adverse health effects may be caused by light pollution or excessive light exposure, and some lighting design textbooks use human health as an explicit criterion for proper interior lighting. Health effects of over-illumination or improper spectral composition of light may include: increased headache incidence, worker fatigue, medically defined stress, decrease in sexual function and increase in anxiety. Likewise, animal models have been studied demonstrating unavoidable light to produce adverse effect on mood and anxiety. For those who need to be awake at night, light at night also has an acute effect on alertness and mood.  In 2007, "shift work that involves circadian disruption" was listed as a probable carcinogen by the World Health Organization's International Agency for Research on Cancer. (IARC Press release No. 180). Multiple studies have documented a correlation between night shift work and the increased incidence of breast and prostate cancer. One

Disruption of ecosystems.

When artificial light affects organisms and ecosystems it is called ecological light pollution. While light at night can be beneficial, neutral, or damaging for individual species, its presence invariably disturbs ecosystems. For example, some species of spiders avoid lit areas, while other species are happy to build their spider web directly on a lamp post. Since lamp posts attract many flying insects, the spiders that don't mind light gain an advantage over the spiders that avoid it. This is a simple example of the way in which species frequencies and food webs can be disturbed by the introduction of light at night.  Light pollution poses a serious threat in particular to nocturnal wildlife, having negative impacts on plant and animal physiology. It can confuse animal navigation, alter

Effect on astronomy.

Astronomy is very sensitive to light pollution. The night sky viewed from a city bears no resemblance to what can be seen from dark skies. Skyglow (the scattering of light in the atmosphere at night) reduces the contrast between stars and galaxies and the sky itself, making it much harder to see fainter objects. This is one factor that has caused newer telescopes to be built in increasingly remote areas.  Even at apparent clear night skies there can be a lot of stray

Increase in atmospheric pollution.

A study presented at the American Geophysical Union meeting in San Francisco found that light pollution destroys nitrate radicals thus

Reduction of natural sky polarization.

In the night, the polarization of the moonlit sky is very strongly reduced in the presence of urban

Reduction.

Reducing light pollution implies many things, such as reducing sky glow, reducing glare, reducing light trespass, and reducing clutter. The method for best reducing light pollution, therefore, depends on exactly what the problem is in any given instance. Possible solutions include:

Improving lighting fixtures.

The use of "full cutoff" lighting fixtures, as much as possible, is advocated by most campaigners for the reduction of light pollution. It is also commonly recommended that lights be spaced appropriately for maximum efficiency, and that number of luminaires being used as well as the wattage of each luminaire match the needs of the particular application (based on local lighting design standards).  Full cutoff fixtures first became available in 1959 with the introduction of General Electric's M100 fixture.  A full cutoff fixture, when correctly installed, reduces the chance for light to escape above the plane of the horizontal. Light released above the horizontal may sometimes be lighting an intended target, but often serves no purpose. When it enters into the atmosphere, light contributes to sky glow. Some governments and organizations are now considering, or have already implemented, full cutoff fixtures in street lamps and stadium lighting.  The use of full cutoff fixtures help to reduce sky glow by preventing light from escaping above the horizontal. Full cutoff typically reduces the visibility of the lamp and reflector within a luminaire, so the effects of glare are also reduced. Campaigners also commonly argue that full cutoff fixtures are more efficient than other fixtures, since light that would otherwise have escaped into the atmosphere may instead be directed towards the ground. However, full cutoff fixtures may also trap more light in the fixture than other types of luminaires, corresponding to lower luminaire efficiency, suggesting a re-design of some luminaires may be necessary.  The use of full cutoff fixtures can allow for lower wattage lamps to be used in the fixtures,

Adjusting types of light sources.

Several different types of light sources exist, each having different properties that affect their appropriateness for certain tasks, particularly efficiency and spectral power distribution. It is often the case that inappropriate light sources have been selected for a task, either due to ignorance or because more sophisticated light sources were unavailable at the time of installation. Therefore, badly chosen light sources often contribute unnecessarily to light pollution and energy waste. By re-assessing and changing the light sources used, it is often possible to reduce energy use and pollutive effects while simultaneously greatly improving efficiency and visibility.  Some types of light sources are listed in order of energy efficiency in the table below (figures are approximate maintained values), and include relative visual skyglow impacts.  Many astronomers request that nearby communities use low pressure sodium lights or amber Aluminium gallium indium phosphide LED as much as possible, because the principal wavelength emitted is comparably easy to work around or in rare cases filter out. The low cost of operating sodium lights is another feature. In 1980, for example, San Jose, California, replaced all street lamps with low pressure sodium lamps, whose light is easier for nearby Lick Observatory to filter out.

Re-designing lighting plans.

In some cases, evaluation of existing plans has determined that more efficient lighting plans are possible. For instance, light pollution can be reduced by turning off unneeded outdoor lights, and lighting stadiums only when there are people inside. Timers are especially valuable for this purpose. One of the world's first coordinated "legislative" efforts to reduce the adverse effect of this pollution on the environment began in Flagstaff, Arizona, in the U.S. There, more than three decades of ordinance development has taken place, with the full support of the population, often with government support, with community advocates, and with the help of major local observatories, including the United States Naval Observatory Flagstaff Station. Each component helps to educate, protect and enforce the imperatives to intelligently reduce detrimental light pollution.  One example of a lighting plan assessment can be seen in a report originally commissioned by the Office of the Deputy Prime Minister in the United Kingdom, and now available through the Department for Communities and Local Government. The report details a plan to be implemented throughout the UK, for designing lighting schemes in the countryside, with a particular focus on preserving the environment.  In another example, the city of Calgary has recently replaced most residential street lights with models that are comparably energy efficient. The motivation is primarily operation cost and environmental conservation. The costs of installation are expected to be regained through energy savings within six to seven years.  The Swiss Agency for Energy Efficiency (SAFE) uses a concept that promises to be of great use in the diagnosis and design of road lighting, ""consommation électrique spécifique" ("CES")", which

Light pollution is the presence of anthropogenic and artificial light in the night environment. It is exacerbated by excessive, misdirected or obtrusive use of light, but even carefully used light fundamentally alters natural conditions. As a major side-effect of urbanization, it is blamed for compromising health, disrupting ecosystems and spoiling aesthetic environments.

Der Begriff der Lichtverschmutzung (), auch Lichtsmog, seltener Lichtverunreinigung genannt, bezeichnet die dauernde Abwesenheit völliger Dunkelheit in den davon betroffenen Gebieten der Erde und bewertet zugleich diesen Sachverhalt negativ. Die Vorgänge, die zu diesem Zustand führen, werden Lichtimmission genannt. Dabei wird der Nachthimmel durch meist künstliche Lichtquellen aufgehellt, besonders wenn das Licht auch nach oben abgestrahlt wird. Das Licht wird in den Luftschichten der Erdatmosphäre gestreut, womit die Überlagerung der natürlichen Dunkelheit verbunden ist. Über Städten spricht man auch von deren Lichtglocke.


Old Nordbahnhof.

In the 19th and 20th centuries, the Mauerpark area served as the location of the Old Nordbahnhof ("Northern Railway Station"), the southern terminus of the Prussian Northern Railway opened in 1877-78, which connected Berlin with the city of Stralsund and the Baltic Sea. Soon after it lost its role as a passenger station to the nearby "Stettiner Bahnhof" and remained in use as a freight yard. In 1950 the "Stettiner Bahnhof" took the name Nordbahnhof because of its role in Berlin's public transportation system, and the Old Nordbahnhof became known as "Güterbahnhof Eberswalder Straße". It was finally closed after the building of the Berlin Wall in 1961.  When viewed from above, one can still see remains of the railroad tracks running towards the former station from the Ringbahn.

Berlin divided.

In 1946, through the division of Berlin into four occupation zones, the land of the Old Nordbahnhof stretching from "Bernauer Straße" to "Kopenhagener Straße" was split between the French and Soviet sectors. After the building of the Berlin Wall, the land was included into the heavily guarded Death Strip with walls on either side. One of the viewing platforms, from which West Berlin residents could look over the wall into East Berlin, stood at this location. The remaining western part of the station was turned into a storehouse and commercial area.  An interesting aspect and a problem for the East German guards was the fact that the anterior part of the Wall strip was located on the steep embankment of the former railway tracks at a higher elevation than the adjacent area in the west. Yet in 1988, the East Berlin authorities concluded an agreement with the West to acquire a strip of land at the bottom of the hill to set up a more efficient border.  After the fall of the Berlin Wall in 1989, the former death strip was designated as a public space and one of several green spaces in the city by local residents. With a contribution of DM 4.5 million from the Allianz environmental fund, the park was built on the eastern half of the former train station. However, the western half, which still belonged to the "Bundeseisenbahnvermögen" real estate association, remained a trade area and since 2004 has served as the location for a flea market next to the park. Several attempts to attach the western part to the green space have so far failed.  Today the park is one of the most popular places for young residents of Berlin, especially from the fashionable district of Prenzlauer Berg, and attracts basketball players, jugglers, musicians, and many other types of people. It is a crowded leisure ground and a site of sustainable improvised nightlife, especially in the summer, and has also become notorious for Walpurgis Night riots in recent years. There are two stadiums next to the park, including Friedrich Ludwig Jahn Sportpark and Max Schmeling Halle, home to several of Berlin's local sports teams.  An 800 m strip of the Berlin Wall still stands in the park today as a monument, and is a popular place for graffiti artists to paint and display their work.  The park has been expanded in several phases since its establishment; construction is underway to bring the park to a total of, with construction scheduled to be completed in 2019.

Culture.

Bearpit Karaoke Show.

A stone circular stage area with surrounding amphitheatre is situated on the hillside directly across from the park's basketball court. In late February 2009 an informal karaoke show took place there for the first time. Weather permitting, the "Bearpit Karaoke Show" at the amphitheatre has continued each year since then to be a regular fixture in the park on Sunday afternoons, with it possible to visit the shows from spring through to late autumn.  Rapidly becoming a Berlin institution, every Sunday afternoon thousands of people make their way to it. If the crowd loves the singer, they will sing and cheer along and make them feel like a star.

Flea market.

Open every Sunday since 2004, Flohmarkt am Mauerpark (German for Mauerpark Flea Market) is popular with both locals and tourists alike. While a newcomer to the Berlin flea market scene, it is becoming a quick favorite. The loose grid stalls populate the western side of the park and offer a collection of new and vintage fashions, vinyl records, CDs, GDR memorabilia and antiques, bicycles and other nicknacks.

Mauerpark is a public linear park in Berlin's Prenzlauer Berg district. The name translates to "Wall Park", referring to its status as a former part of the Berlin Wall and its Death Strip. The park is located at the border of Prenzlauer Berg and Gesundbrunnen district of former West Berlin.

Der Mauerpark ist eine Parkanlage in Berlin. Sein Name geht auf die 1961 errichtete Berliner Mauer zurück, die an dieser Stelle die Grenze zwischen den damaligen Bezirken Prenzlauer Berg und Wedding bildete. Hier verläuft die Grenze zwischen den Ortsteilen Prenzlauer Berg (Bezirk Pankow) und Gesundbrunnen (Bezirk Mitte). Im Westen liegt das zu Gesundbrunnen gehörende Brunnenviertel, im Osten das zu Prenzlauer Berg gehörende Gleimviertel. Das langgestreckte Freigelände verläuft entlang des für den Kraftverkehr gesperrten Abschnitts der Schwedter Straße zwischen Eberswalder und Bernauer Straße sowie der Ringbahn. Da es im dichtbebauten Prenzlauer Berg vergleichsweise wenige Grünflächen gibt, hat sich der Mauerpark zu einem beliebten Ort der Naherholung entwickelt, der vor allem am Wochenende Künstlern, Musikern und Familien eine Heimstatt bietet und sich dadurch auch über Berlin hinaus einen Namen gemacht hat.


History.

Uranium minerals were noticed by miners for a long time prior to the discovery of uranium in 1789. The uranium mineral pitchblende, also known as uraninite, was reported from the Krušné hory (Ore Mountains), Saxony, as early as 1565. Other early reports of pitchblende date from 1727 in Jáchymov and 1763 in Schwarzwald.  In the early 19th century, uranium ore was recovered as a byproduct of mining in Saxony, Bohemia, and Cornwall. The first deliberate mining of radioactive ores took place in Jáchymov, a silver-mining city in the Czech Republic. Marie Skłodowska-Curie used pitchblende ore from Jáchymov to isolate the element radium, a decay product of uranium. Until World War II, uranium was mined primarily for its radium content; some carnotite deposits were mined primarily for the vanadium content. Sources for radium, contained in the uranium ore, were sought for use as luminous paint for watch dials and other instruments, as well as for health-related applications, some of which in retrospect were certainly harmful. The byproduct uranium was used mostly as a yellow pigment.  In the United States, the first radium/uranium ore was discovered in 1871 in gold mines near Central City, Colorado. This district produced about 50 tons of high grade ore between 1871 and 1895. Most American uranium ore before World War II came from vanadium deposits on the Colorado Plateau of Utah and Colorado.  In Cornwall, England, the South Terras Mine near St. Stephen opened for uranium production in 1873, and produced about 175 tons of ore before 1900. Other early uranium mining occurred in Autunois in France's Massif Central, Oberpfalz in Bavaria, and Billingen in Sweden.  The Shinkolobwe deposit in Katanga, Belgian Congo now Shaba Province, Democratic Republic of the Congo (DRC) was discovered in 1913, and exploited by the Union Minière du Haut Katanga. Other important early deposits include Port Radium, near Great Bear Lake, Canada discovered in 1931, along with Beira Province, Portugal; Tyuya Muyun, Uzbekistan, and Radium Hill, Australia.  Because of the need for the uranium for bomb research during World War II, the Manhattan Project used a variety of sources for the element. The Manhattan Project initially purchased uranium ore from the Belgian Congo, through the Union Minière du Haut Katanga. Later the project contracted with vanadium mining companies in the American Southwest. Purchases were also made from the Eldorado Mining and Refining Limited company in Canada. This company had large stocks of uranium as waste from its radium refining activities.  American uranium ores mined in Colorado were mixed ores of vanadium and uranium, but because of wartime secrecy, the Manhattan Project would publicly admit only to purchasing the vanadium, and did not pay the uranium miners for the uranium content. In a much later lawsuit, many miners were able to reclaim lost profits from the U.S. government. American ores had much lower uranium concentrations than the ore from the Belgian Congo, but they were pursued vigorously to ensure nuclear self-sufficiency.  Similar efforts were undertaken in the Soviet Union, which did not have native stocks of uranium when it started developing its own atomic weapons program.  Intensive exploration for uranium started after the end of World War II as a result of the military and civilian demand for uranium. There were three separate periods of uranium exploration or "booms." These were from 1956 to 1960, 1967 to 1971, and from 1976 to 1982.  In the 20th century, the United States was the world's largest uranium producer. Grants Uranium District in northwestern New Mexico was the largest United States uranium producer. The Gas Hills Uranium District was the second largest uranium producer. The famous Lucky Mc Mine is located in the Gas Hills near Riverton, Wyoming. Canada has since surpassed the United States as the cumulative largest producer in the world. In 1990, 55% of world production came from underground mines, but this shrank to 33% by 1999. From 2000, new Canadian mines again increased the proportion of underground mining, and with Olympic Dam it is now 37%. In situ leach (ISL, or ISR) mining has been steadily increasing its share of the total, mainly due to Kazakhstan.

Deposit types.

Many different types of uranium deposits have been discovered and mined. There are mainly three types of uranium deposits including unconformity-type deposits, namely paleoplacer deposits and sandstone-type also known as roll front type deposits.  Uranium deposits are classified into 15 categories according to their geological setting and the type of rock in which they are found. This geological classification system is determined by the International Atomic Energy Agency (IAEA).

Sedimentary.

Uranium deposits in sedimentary rocks include those in sandstone (in Canada and the western US), Precambrian unconformities (in Canada), phosphate, Precambrian quartz-pebble conglomerate, collapse breccia pipes (see Arizona breccia pipe uranium mineralization), and calcrete.  Sandstone uranium deposits are generally of two types. "Roll-front" type deposits occur at the boundary between the up dip and oxidized part of a sandstone body and the deeper down dip reduced part of a sandstone body. "Peneconcordant" sandstone uranium deposits, also called "Colorado Plateau"-type deposits, most often occur within generally oxidized sandstone bodies, often in localized reduced zones, such as in association with carbonized wood in the sandstone.  Precambrian quartz-pebble conglomerate-type uranium deposits occur only in rocks older than two billion years old. The conglomerates also contain pyrite. These deposits have been mined in the Blind River-Elliot Lake district of Ontario, Canada, and from the gold-bearing Witwatersrand conglomerates of South Africa.  Unconformity-type deposits make up about 33% of the World Outside Centrally Planned Economies Areas (WOCA)'s uranium deposits.

Igneous or hydrothermal.

Hydrothermal uranium deposits encompass the vein-type uranium ores. Igneous deposits include nepheline syenite intrusives at Ilimaussaq, Greenland; the disseminated uranium deposit at Rossing, Namibia; and uranium-bearing pegmatites. Disseminated deposits are also found in the states of Washington and Alaska in the US.

Breccial.

Breccial uranium deposits are found in rocks that have been broken due to tectonic fracturing, or weathering. Breccia uranium deposits are most common in India, Australia and the United States.  Olympic Dam mine is the world's largest uranium deposit and home to the Olympic Dam Centre, a mining company currently owned by BHP Billiton.

Exploration.

Uranium prospecting is similar to other forms of mineral exploration with the exception of some specialized instruments for detecting the presence of radioactive isotopes.  The Geiger counter was the original radiation detector, recording the total count rate from all energy levels of radiation. Ionization chambers and Geiger counters were first adapted for field use in the 1930s. The first transportable Geiger–Müller counter (weighing 25 kg) was constructed at the University of British Columbia in 1932. H.V. Ellsworth of the GSC built a lighter weight, more practical unit in 1934. Subsequent models were the principal instruments used for uranium prospecting for many years, until geiger counters were replaced by scintillation counters.  The use of airborne detectors to prospect for radioactive minerals was first proposed by G.C. Ridland, a geophysicist working at Port Radium in 1943. In 1947, the earliest recorded trial of airborne radiation detectors (ionization chambers and Geiger counters) was conducted by Eldorado Mining and Refining Limited. (a Canadian Crown Corporation since sold to become Cameco Corporation). The first patent for a portable gamma-ray spectrometer was filed by Professors Pringle, Roulston & Brownell of the University of Manitoba in 1949, the same year as they tested the first portable scintillation counter on the ground and in the air in northern Saskatchewan.  Airborne gamma-ray spectrometry is now the accepted leading technique for uranium prospecting with worldwide applications for geological mapping, mineral exploration & environmental monitoring. Airborne gamma-ray spectrometry used specifically for uranium measurement and prospecting must account for a number of factors like the distance between the source and the detector and the scattering of radiation through the minerals, surrounding earth and even in the air. In Australia, a Weathering Intensity Index has been developed to help prospectors based on the Shuttle Radar Topography Mission (SRTM) elevation and airborne gamma-ray spectrometry images.  A deposit of uranium, discovered by geophysical techniques, is evaluated and sampled to determine the amounts of uranium materials that are extractable at specified costs from the deposit. Uranium reserves are the amounts of ore that are estimated to be recoverable at stated costs.

Techniques.

As with other types of hard rock mining there are several methods of extraction. In 2012, the percentage of the mined uranium produced by each mining method was: in-situ leach (44.9 percent), underground mining (26.2 percent), open pit (19.9 percent), and heap leaching (1.7 percent). The remaining 7.3% was derived as a byproduct of mining for other minerals, and miscellaneous recovery.

Open pit.

In open pit mining, overburden is removed by drilling and blasting to expose the ore body, which is then mined by blasting and excavation using loaders and dump trucks. Workers spend much time in enclosed cabins thus limiting exposure to radiation. Water is extensively used to suppress airborne dust levels.

Underground.

If the uranium is too far below the surface for open pit mining, an underground mine might be used with tunnels and shafts dug to access and remove uranium ore. There is less waste material removed from underground mines than open pit mines, however this type of mining exposes underground workers to the highest levels of radon gas.  Underground uranium mining is in principle no different from any other hard rock mining and other ores are often mined in association (e.g., copper, gold, silver). Once the ore body has been identified a shaft is sunk in the vicinity of the ore veins, and crosscuts are driven horizontally to the veins at various levels, usually every 100 to 150 metres. Similar tunnels, known as drifts, are driven along the ore veins from the crosscut. To extract the ore, the next step is to drive tunnels, known as raises when driven upwards and winzes when driven downwards, through the deposit from level to level. Raises are subsequently used to develop the stopes where the ore is mined from the veins.  The stope, which is the workshop of the mine, is the excavation from which the ore is extracted. Three methods of stope mining are commonly used. In the "cut and fill" or "open stoping" method, the space remaining following removal of ore after blasting is filled with waste rock and cement. In the "shrinkage" method, only sufficient broken ore is removed via the chutes below to allow miners working from the top of the pile to drill and blast the next layer to be broken off, eventually leaving a large hole. The method known as "room and pillar" is used for thinner, flatter ore bodies. In this method the ore body is first divided into blocks by intersecting drives, removing ore while so doing, and then systematically removing the blocks, leaving enough ore for roof support.  The health effects discovered from radon exposure in unventilated uranium mining prompted the switch away from uranium mining via tunnel mining towards open cut and in-situ leaching technology, a method of extraction that does not produce the same occupational hazards, or mine tailings, as conventional mining.  With regulations in place to ensure the use of high volume ventilation technology if any confined space uranium mining is occurring, occupational exposure and mining deaths can be largely eliminated. The Olympic Dam and Canadian underground mines are ventilated with powerful fans with radon levels being kept at a very low to practically "safe level" in uranium mines. Naturally occurring radon in other, non-uranium mines, also may need control by ventilation.

Heap leaching.

Heap leaching is an extraction process by which chemicals (usually sulfuric acid) are used to extract the economic element from ore which has been mined and placed in piles on the surface. Heap leaching is generally economically feasible only for oxide ore deposits. Oxidation of sulfide deposits occurs during the geological process called weathering. Therefore, oxide ore deposits are typically found close to the surface. If there are no other economic elements within the ore a mine might choose to extract the uranium using a leaching agent, usually a low molar sulfuric acid.  If the economic and geological conditions are right, the mining company will level large areas of land with a small gradient, layering it with thick plastic (usually HDPE or LLDPE), sometimes with clay, silt or sand beneath the plastic liner. The extracted ore will typically be run through a crusher and placed in heaps atop the plastic. The leaching agent will then be sprayed on the ore for 30–90 days. As the leaching agent filters through the heap, the uranium will break its bonds with the oxide rock and enter the solution. The solution will then filter along the gradient into collecting pools which will then be pumped to on-site plants for further processing. Only some of the uranium (commonly about 70%) is actually extracted.  The uranium concentrations within the solution are very important for the efficient separation of pure uranium from the acid. As different heaps will yield different concentrations, the solution is pumped to a mixing plant that is carefully monitored. The properly balanced solution is then pumped into a processing plant where the uranium is separated from the sulfuric acid.  Heap leach is significantly cheaper than traditional milling processes. The low costs allow for lower grade ore to be economically feasible (given that it is the right type of ore body). Environmental law requires that the surrounding ground water is continually monitored for possible contamination. The mine will also have to have continued monitoring even after the shutdown of the mine. In the past mining companies would sometimes go bankrupt, leaving the responsibility of mine reclamation to the public. Recent additions to the mining law require that companies set aside the money for reclamation before the beginning of the project. The money will be held by the public to insure adherence to environmental standards if the company were to ever go bankrupt.

"In-situ" leaching.

In-situ leaching (ISL), also known as solution mining, or in-situ recovery (ISR) in North America, involves leaving the ore where it is in the ground, and recovering the minerals from it by dissolving them and pumping the pregnant solution to the surface where the minerals can be recovered. Consequently, there is little surface disturbance and no tailings or waste rock generated. However, the orebody needs to be permeable to the liquids used, and located so that they do not contaminate ground water away from the orebody.  Uranium ISL uses the native groundwater in the orebody which is fortified with a complexing agent and in most cases an oxidant. It is then pumped through the underground orebody to recover the minerals in it by leaching. Once the pregnant solution is returned to the surface, the uranium is recovered in much the same way as in any other uranium plant (mill).  In Australian ISL mines (Beverley, Four Mile and Honeymoon Mine) the oxidant used is hydrogen peroxide and the complexing agent sulfuric acid. Kazakh ISL mines generally do not employ an oxidant but use much higher acid concentrations in the circulating solutions. ISL mines in the USA use an alkali leach due to the presence of significant quantities of acid-consuming minerals such as gypsum and limestone in the host aquifers. Any more than a few percent carbonate minerals means that alkali leach must be used in preference to the more efficient acid leach.  The Australian government has published a best practice guide for in situ leach mining of uranium, which is being revised to take account of international differences.

Seawater recovery.

The uranium concentration of sea water is low, approximately 3.3 parts per billion or 3.3 micrograms per liter of seawater. But the quantity of this resource is gigantic and some scientists believe this resource is practically limitless with respect to world-wide demand. That is to say, if even a portion of the uranium in seawater could be used the entire world's nuclear power generation fuel could be provided over a long time period. Some anti-nuclear proponents claim this statistic is exaggerated. Although research and development for recovery of this low-concentration element by inorganic adsorbents such as titanium oxide compounds has occurred since the 1960s in the United Kingdom, France, Germany, and Japan, this research was halted due to low recovery efficiency.  At the Takasaki Radiation Chemistry Research Establishment of the Japan Atomic Energy Research Institute (JAERI Takasaki Research Establishment), research and development has continued culminating in the production of absorbent by irradiation of polymer fiber. Absorbents have been synthesized that have a functional group (amidoxime group) that selectively adsorbs heavy metals, and the performance of such adsorbents has been improved. Uranium absorption capacity of the polymer fiber absorbent is high, approximately tenfold greater in comparison to the conventional titanium oxide absorbent.  One method of extracting uranium from seawater is using a uranium-specific nonwoven fabric as an adsorbent. The total amount of uranium recovered from three collection boxes containing 350 kg of fabric was >1 kg of yellowcake after 240 days of submersion in the ocean. According to the OECD, uranium may be extracted from seawater using this method for about $300/kg-U. The experiment by Seko "et al." was repeated by Tamada et al. in 2006. They found that the cost varied from ¥15,000 to ¥88,000 depending on assumptions and "The lowest cost attainable now is ¥25,000 with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses." With the May, 2008 exchange rate, this was about $240/kg-U.  In 2012, ORNL researchers announced the successful development of a new adsorbent material dubbed "HiCap", which vastly outperforms previous best adsorbents, which perform surface retention of solid or gas molecules, atoms or ions. "We have shown that our adsorbents can extract five to seven times more uranium at uptake rates seven times faster than the world's best adsorbents," said Chris Janke, one of the inventors and a member of ORNL's Materials Science and Technology Division. HiCap also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory.

Uranium prices.

Since 1981 uranium prices and quantities in the US are reported by the Department of Energy. The import price dropped from 32.90 US$/lb-UO in 1981 down to 12.55 in 1990 and to below 10 US$/lb-UO in the year 2000. Prices paid for uranium during the 1970s were higher, 43 US$/lb-UO is reported as the selling price for Australian uranium in 1978 by the Nuclear Information Centre. Uranium prices reached an all-time low in 2001, costing US$7/lb, but in April 2007 the price of Uranium on the spot market rose to US$113.00/lb, a high point of the uranium bubble of 2007. This was very close to the all time high (adjusted for inflation) in 1977.  Following the 2011 Fukushima nuclear disaster, the global uranium sector remained depressed with the uranium price falling more than 50%, declining share values, and reduced profitability of uranium producers since March 2011 and into 2014. As a result, uranium companies worldwide are reducing costs, and limiting operations. As an example, Westwater Resources (previously Uranium Resources), has had to cease all uranium operations due to unfavorable prices. Since then, Westwater has tried branching out into other markets, namely lithium and graphite.  As of July 2014, the price of uranium concentrate remained near a five-year low, the uranium price having fallen more than 50% from the peak spot price in January 2011, reflecting the loss of Japanese demand following the 2011 Fukushima nuclear disaster. As a result of continued low prices, in February 2014 mining company Cameco deferred plans to expand production from existing Canadian mines, although it continued work to open a new mine at Cigar Lake. Also in February 2014, Paladin energy suspended operations at its mine in Malawi, saying that the high-cost operation was losing money at current prices.

Politics.

In the beginning of the Cold War, to ensure adequate supplies of uranium for national defense, the United States Congress passed the U.S. Atomic Energy Act of 1946, creating the Atomic Energy Commission (AEC) which had the power to withdraw prospective uranium mining land from public purchase, and also to manipulate the price of uranium to meet national needs. By setting a high price for uranium ore, the AEC created a uranium "boom" in the early 1950s, which attracted many prospectors to the Four Corners region of the country. Moab, Utah became known as the Uranium-capital of the world, when geologist Charles Steen discovered such an ore in 1952, even though American ore sources were considerably less potent than those in the Belgian Congo or South Africa.  In the 1950s methods for extracting diluted uranium and thorium, found in abundance in granite or seawater, were pursued. Scientists speculated that, used in a breeder reactor, these materials would potentially provide limitless source of energy.  American military requirements declined in the 1960s, and the government completed its uranium procurement program by the end of 1970. Simultaneously, a new market emerged: commercial nuclear power plants. In the U.S. this market virtually collapsed by the end of the 1970s as a result of industrial strains caused by the energy crisis, popular opposition, and finally the Three Mile Island nuclear accident in 1979, all of which led to a "de facto" moratorium on the development of new nuclear reactor power stations.  In Europe a mixed situation exists. Considerable nuclear power capacities have been developed, notably in Belgium, Finland, France, Germany, Spain, Sweden, Switzerland, and the UK. In many countries development of nuclear power has been stopped and phased out by legal actions. In Italy the use of nuclear power was barred by a referendum in 1987; this is now under revision. Ireland in 2008 also had no plans to change its non-nuclear stance, although since the opening in 2012 of the East-West Interconnector between Ireland and Britain, it has been supported by British nuclear power.  The years 1976 and 1977 saw uranium mining become a major political issue in Australia, with the Ranger Inquiry (Fox) report opening up a public debate about uranium mining. The Movement Against Uranium Mining group was formed in 1976, and many protests and demonstrations against uranium mining were held. Concerns relate to the health risks and environmental damage from uranium mining. Notable Australian anti-uranium activists have included Kevin Buzzacott, Jacqui Katona, Yvonne Margarula, and Jillian Marsh.  The World Uranium Hearing was held in Salzburg, Austria in September 1992. Anti-nuclear speakers from all continents, including indigenous speakers and scientists, testified to the health and environmental problems of uranium mining and processing, nuclear power, nuclear weapons, nuclear tests, and radioactive waste disposal. People who spoke at the 1992 Hearing include: Thomas Banyacya, Katsumi Furitsu, Manuel Pino and Floyd Red Crow Westerman. They highlighted the threat of radioactive contamination to all peoples, especially indigenous communities and said that their survival requires self-determination and emphasis on spiritual and cultural values. Increased renewable energy commercialization was advocated.

Health risks.

Lung cancer.

Uranium ore emits radon gas. The health effects of high exposure to radon are a particular problem in the mining of uranium; significant excess lung cancer deaths have been identified in epidemiological studies of uranium miners employed in the 1940s and 1950s. The first major studies with radon and health occurred in the context of uranium mining, first in the Joachimsthal region of Bohemia and then in the Southwestern United States during the early Cold War. Because radon is a product of the radioactive decay of uranium, underground uranium mines may have high concentrations of radon. Many uranium miners in the Four Corners region contracted lung cancer and other pathologies as a result of high levels of exposure to radon in the mid-1950s. The increased incidence of lung cancer was particularly pronounced among Native American and Mormon miners, because those groups normally have low rates of lung cancer. Safety standards requiring expensive ventilation were not widely implemented or policed during this period.  In studies of uranium miners, workers exposed to radon levels of 50 to 150 picocuries of radon per liter of air (2000–6000 Bq/m) for about 10 years have shown an increased frequency of lung cancer. Statistically significant excesses in lung cancer deaths were present after cumulative exposures of less than 50 WLM. There is unexplained heterogeneity in these results (whose confidence interval do not always overlap). The size of the radon-related increase in lung cancer risk varied by more than an order of magnitude between the different studies.  Since that time, ventilation and other measures have been used to reduce radon levels in most affected mines that continue to operate. In recent years, the average annual exposure of uranium miners has fallen to levels similar to the concentrations inhaled in some homes. This has reduced the risk of occupationally induced cancer from radon, although it still remains an issue both for those who are currently employed in affected mines and for those who have been employed in the past. The power to detect any excess risks in miners nowadays is likely to be small, exposures being much smaller than in the early years of mining.

United States clean-up efforts.

Despite efforts made in cleaning up uranium sites, significant problems stemming from the legacy of uranium development still exist today on the Navajo Nation and in the states of Utah, Colorado, New Mexico, and Arizona. Hundreds of abandoned mines have not been cleaned up and present environmental and health risks in many communities. At the request of the U.S. House Committee on Oversight and Government Reform in October 2007, and in consultation with the Navajo Nation, the Environmental Protection Agency (EPA), along with the Bureau of Indian Affairs (BIA), the Nuclear Regulatory Commission (NRC), the Department of Energy (DOE), and the Indian Health Service (IHS), developed a coordinated Five-Year Plan to address uranium contamination. Similar interagency coordination efforts are beginning in the State of New Mexico as well. In 1978, Congress passed the Uranium Mill Tailings Radiation Control Act (UMTRCA), a measure designed to assist in the cleanup of 22 inactive ore-processing sites throughout the southwest. This also included constructing 19 disposal sites for the tailings, which contain a total of 40 million cubic yards of low-level radioactive material. The Environmental Protection Agency estimates that there are 4000 mines with documented uranium production, and another 15,000 locations with uranium occurrences in 14 western states, most found in the Four Corners area and Wyoming.  The "Uranium Mill Tailings Radiation Control Act" is a United States environmental law that amended the Atomic Energy Act of 1954 and gave the Environmental Protection Agency the authority to establish health and environmental standards for the stabilization, restoration, and disposal of uranium mill waste. Title 1 of the Act required the EPA to set environmental protection standards consistent with the Resource Conservation and Recovery Act, including groundwater protection limits; the Department of Energy to implement EPA standards and provide perpetual care for some sites; and the Nuclear Regulatory Commission to review cleanups and license sites to states or the DOE for perpetual care. Title 1 established a uranium mill remedial action program jointly funded by the federal government and the state. Title 1 of the Act also designated 22 inactive uranium mill sites for remediation, resulting in the containment of 40 million cubic yards of low-level radioactive material in UMTRCA Title 1 holding cells.

Uranium mining is the process of extraction of uranium ore from the ground. The worldwide production of uranium in 2015 amounted to 60,496 tonnes. Kazakhstan, Canada, and Australia are the top three producers and together account for 70% of world uranium production. Other important uranium producing countries in excess of 1,000 tons per year are Niger, Russia, Namibia, Uzbekistan, China, the United States and Ukraine. Uranium from mining is used almost entirely as fuel for nuclear power plants.

Uranbergbau ist die Gewinnung von Uran aus Uranlagerstätten. Die größten Uranbergbauländer sind Kanada, Australien, Kasachstan, Russland, Niger, Namibia, Usbekistan und die USA. Rund 70 % der bekannten Uranvorräte Nordamerikas finden sich auf indigenem Land. Uran kann auch aus der Asche von Kohlekraftwerken gewonnen werden.


Early life and education.

Gabriel Lippmann was born in Bonnevoie, Luxembourg (Luxembourgish: Bouneweg), on 16 August 1845. At the time, Bonnevoie was part of the commune of Hollerich (Luxembourgish: Hollerech) which is often given as his place of birth. (Both places, Bonnevoie and Hollerich, are now districts of Luxembourg City.) His father, Isaïe, a French Jew born in Ennery near Metz, managed the family glove-making business at the former convent in Bonnevoie. In 1848, the family moved to Paris where Lippmann was initially tutored by his mother, Miriam Rose (Lévy), before attending the Lycée Napoléon (now Lycée Henri-IV). He was said to have been a rather inattentive but thoughtful pupil with a special interest in mathematics. In 1868, he was admitted to the École normale supérieure in Paris where he failed the agrégation examination which would have enabled him to enter the teaching profession, preferring instead to study physics. In 1872, the French government sent him on a mission to Heidelberg University where he was able to specialize in electricity with the encouragement of Gustav Kirchhoff, receiving a doctorate with "summa cum laude" distinction in 1874. Lippmann then returned to Paris in 1875, where he continued to study until 1878, when he became professor of physics at the Sorbonne.

Career.

Lippmann made several important contributions to various branches of physics over the years.

The capillary electrometer.

One of Lippmann's early discoveries was the relationship between electrical and capillary phenomena which allowed him to develop a sensitive capillary electrometer, subsequently known as the Lippmann electrometer which was used in the first ECG machine. In a paper delivered to the Philosophical Society of Glasgow on 17 January 1883, John G. M'Kendrick described the apparatus as follows:  Lippmann's PhD thesis, presented to the Sorbonne on 24 July 1875, was on electrocapillarity.

Piezoelectricity.

In 1881, Lippmann predicted the converse piezoelectric effect.

Colour photography.

Above all, Lippmann is remembered as the inventor of a method for reproducing colours by photography, based on the interference phenomenon, which earned him the Nobel Prize in Physics for 1908.  In 1886, Lippmann's interest turned to a method of fixing the colours of the solar spectrum on a photographic plate. On 2 February 1891, he announced to the Academy of Sciences: "I have succeeded in obtaining the image of the spectrum with its colours on a photographic plate whereby the image remains fixed and can remain in daylight without deterioration." By April 1892, he was able to report that he had succeeded in producing colour images of a stained glass window, a group of flags, a bowl of oranges topped by a red poppy and a multicoloured parrot. He presented his theory of colour photography using the interference method in two papers to the Academy, one in 1894, the other in 1906.  The interference phenomenon in optics occurs as a result of the wave propagation of light. When light of a given wavelength is reflected back upon itself by a mirror, standing waves are generated, much as the ripples resulting from a stone dropped into still water create standing waves when reflected back by a surface such as the wall of a pool. In the case of ordinary incoherent light, the standing waves are distinct only within a microscopically thin volume of space next to the reflecting surface.  Lippmann made use of this phenomenon by projecting an image onto a special photographic plate capable of recording detail smaller than the wavelengths of visible light. The light passed through the supporting glass sheet into a very thin and nearly transparent photographic emulsion containing submicroscopically small silver halide grains. A temporary mirror of liquid mercury in intimate contact reflected the light back through the emulsion, creating standing waves whose nodes had little effect while their antinodes created a latent image. After development, the result was a structure of laminae, distinct parallel layers composed of submicroscopic metallic silver grains, which was a permanent record of the standing waves. In each part of the image, the spacing of the laminae corresponded to the half-wavelengths of the light photographed.  The finished plate was illuminated from the front at a nearly perpendicular angle, using daylight or another source of white light containing the full range of wavelengths in the visible spectrum. At each point on the plate, light of approximately the same wavelength as the light which had generated the laminae was strongly reflected back toward the viewer. Light of other wavelengths which was not absorbed or scattered by the silver grains simply passed through the emulsion, usually to be absorbed by a black anti-reflection coating applied to the back of the plate after it had been developed. The wavelengths, and therefore the colours, of the light which had formed the original image were thus reconstituted and a full-colour image was seen.  In practice, the Lippmann process was not easy to use. Extremely fine-grained high-resolution photographic emulsions are inherently much less light-sensitive than ordinary emulsions, so long exposure times were required. With a lens of large aperture and a very brightly sunlit subject, a camera exposure of less than one minute was sometimes possible, but exposures measured in minutes were typical. Pure spectral colours reproduced brilliantly, but the ill-defined broad bands of wavelengths reflected by real-world objects could be problematic. The process did not produce colour prints on paper and it proved impossible to make a good duplicate of a Lippmann colour photograph by rephotographing it, so each image was unique. A very shallow-angled prism was usually cemented to the front of the finished plate to deflect unwanted surface reflections, and this made plates of any substantial size impractical. The lighting and viewing arrangement required to see the colours to best effect precluded casual use. Although the special plates and a plate holder with a built-in mercury reservoir were commercially available for a few years circa 1900, even expert users found consistent good results elusive and the process never graduated from being a scientifically elegant laboratory curiosity. It did, however, stimulate interest in the further development of colour photography.  Lippmann's process foreshadowed laser holography, which is also based on recording standing waves in a photographic medium. Denisyuk reflection holograms, often referred to as Lippmann-Bragg holograms, have similar laminar structures that preferentially reflect certain wavelengths. In the case of actual multiple-wavelength colour holograms of this type, the colour information is recorded and reproduced just as in the Lippmann process, except that the highly coherent laser light passing through the recording medium and reflected back from the subject generates the required distinct standing waves throughout a relatively large volume of space, eliminating the need for reflection to occur immediately adjacent to the recording medium. Unlike Lippmann colour photography, however, the lasers, the subject and the recording medium must all be kept stable to within one quarter of a wavelength during the exposure in order for the standing waves to be recorded adequately or at all.

Integral photography.

In 1908, Lippmann introduced what he called "integral photography," in which a plane array of closely spaced, small, spherical lenses is used to photograph a scene, recording images of the scene as it appears from many slightly different horizontal and vertical locations. When the resulting images are rectified and viewed through a similar array of lenses, a single integrated image, composed of small portions of all the images, is seen by each eye. The position of the eye determines which parts of the small images it sees. The effect is that the visual geometry of the original scene is reconstructed, so that the limits of the array seem to be the edges of a window through which the scene appears life-size and in three dimensions, realistically exhibiting parallax and perspective shift with any change in the position of the observer. This principle of using numerous lenses or imaging apertures to record what was later termed a light field underlies the evolving technology of light-field cameras and microscopes.  When Lippmann presented the theoretical foundations of his "integral photography" in March 1908, it was impossible to accompany them with concrete results. At the time, the materials necessary for producing a lenticular screen with the proper optical qualities were lacking. In the 1920s, promising trials were made by Eugène Estanave, using glass Stanhope lenses, and by Louis Lumière, using celluloid. Lippmann's integral photography was the foundation of research on 3D and animated lenticular imagery and also on color lenticular processes.

Measurement of time.

In 1895, Lippmann evolved a method of eliminating the personal equation in measurements of time, using photographic registration, and he studied the eradication of irregularities of pendulum clocks, devising a method of comparing the times of oscillation of two pendulums of nearly equal period.

The coelostat.

Lippmann also invented the coelostat, an astronomical tool that compensated for the Earth's rotation and allowed a region of the sky to be photographed without apparent movement.

Academic affiliations.

Lippmann was a member of the Academy of Sciences from 8 February 1886 until his death, serving as its president in 1912. In addition, he was a Foreign Member of the Royal Society of London, a member of the Bureau des Longitudes, and a member of the Grand Ducal Institute of Luxembourg. He became a member of the Société française de photographie in 1892 and its president from 1896 to 1899. Lippmann was one of the founders of the Institut d'optique théorique et appliquée in France. Lippmann was the President of the Société Astronomique de France (SAF), the French astronomical society, from 1903–1904.

Honours.

In Luxembourg City an Institute for fundamental scientific research was named after Lippmann ("Centre de Recherche Public Gabriel Lippmann") which merged on 1 January 2015 with another major research centre to form the new Luxembourg Institute for Science and Technology (LIST).

Personal life.

Lippmann married the daughter of the novelist Victor Cherbuliez in 1888. He died on 13 July 1921 aboard the steamer "France" while en route from Canada.

Jonas Ferdinand Gabriel Lippmann (16 August 1845 – 13 July 1921) was a Franco-Luxembourgish physicist and inventor, and Nobel laureate in physics for his method of reproducing colours photographically based on the phenomenon of interference.

Jonas Ferdinand Gabriel Lippmann (* 16. August 1845 in Bonneweg (Bonnevoie), damals Gemeinde Hollerich, Luxemburg; † 13. Juli 1921 im Atlantik auf der "France" auf der Fahrt von New York nach Le Havre) war ein französischer Physiker und Nobelpreisträger für Physik.


Etymology.

The English word "translation" derives from the Latin word "translatio", which comes from "", "across" + "", "to carry" or "to bring" ("-latio" in turn coming from "latus", the past participle of "ferre"). Thus "translatio" is "a carrying across" or "a bringing across": in this case, of a text from one language to another.  Some Slavic languages and the Germanic languages (other than Dutch and Afrikaans) have d their words for the concept of "translation" on "translatio".  The Romance languages and the remaining "Slavic" languages have derived their words for the concept of "translation"

Theories.

Western theory.

Discussions of the theory and practice of translation reach back into antiquity and show remarkable continuities. The ancient Greeks distinguished between "metaphrase" (literal translation) and "paraphrase". This distinction was adopted by English poet and translator John Dryden (1631–1700), who described translation as the judicious blending of these two modes of phrasing when selecting, in the target language, "counterparts," or equivalents, for the expressions used in the source language:  Dryden cautioned, however, against the license of "imitation", i.e., of adapted translation: "When a painter copies from the life... he has no privilege to alter features and lineaments..."  This general formulation of the central concept of translation—equivalence—is as adequate as any that has been proposed since Cicero and Horace, who, in 1st-century-BCE Rome, famously and literally cautioned against translating "word for word"

Other traditions.

Due to Western colonialism and cultural dominance in recent centuries, Western translation traditions have largely replaced other traditions. The Western traditions draw on both ancient and medieval traditions, and on more recent European innovations.  Though earlier approaches to translation are less commonly used today, they retain importance when dealing with their products, as when historians view ancient or medieval records to piece together events which took place in non-Western or pre-Western environments. Also, though heavily influenced by Western traditions and practiced by translators taught in Western-style educational systems, Chinese and related translation traditions retain some theories and philosophies unique to the Chinese tradition.

Near East.

Traditions of translating material among the languages of ancient Egypt, Mesopotamia, Assyria (Syriac language), Anatolia, and Israel (Hebrew language) go back several millennia. There exist partial translations

Asia.

There is a separate tradition of translation in South, Southeast and East Asia (primarily of texts from the Indian and Chinese civilizations), connected especially with the rendering of religious, particularly Buddhist, texts and with the governance of the Chinese empire. Classical Indian translation is characterized by loose adaptation, rather than the closer translation more commonly found in Europe; and Chinese translation theory identifies various criteria and limitations in translation.  In the East Asian sphere of Chinese cultural influence, more important than translation "per se" has been the use and reading of Chinese

Islamic world.

Translation of material into Arabic expanded after the creation of Arabic script in the 5th century, and gained great importance with the rise of Islam and Islamic empires. Arab translation initially focused primarily on politics, rendering Persian, Greek, even Chinese and Indic diplomatic materials into Arabic. It later focused on translating classical Greek and Persian works, as well as some Chinese and Indian texts, into Arabic for scholarly study at major Islamic learning centers, such as the Al-Karaouine (Fes, Morocco), Al-Azhar (Cairo, Egypt), and the Al-Nizamiyya of Baghdad. In terms of theory, Arabic translation drew heavily on earlier Near Eastern traditions as well as more contemporary Greek and Persian traditions.  Arabic translation efforts and techniques are important to Western translation traditions due to centuries of close contacts and exchanges. Especially after the Renaissance, Europeans began more intensive study of Arabic and Persian translations of classical works as well as scientific and philosophical works of Arab and oriental origins. Arabic, and to a lesser degree Persian, became important sources of material and perhaps of techniques for revitalized Western traditions, which in time would overtake the Islamic and oriental traditions.  In the 19th century, after the Middle East's Islamic clerics and copyists A translator who contributed mightily to the advance of the Islamic Enlightenment was the Egyptian cleric Rifaa al-Tahtawi (1801–73), who had spent five years in Paris in the late 1820s, teaching religion to Muslim students. After returning to Cairo with the encouragement

Fidelity and transparency.

Fidelity (or "faithfulness") and felicity (or transparency), dual ideals in translation, are often (though not always) at odds. A 17th-century French critic coined the phrase "" to suggest that translations can be either faithful or beautiful, but not both. Fidelity is the extent to which a translation accurately renders the meaning of the source text, without distortion. Transparency is the extent to which a translation appears to a native speaker of the target language to have originally been written in that language, and conforms to its grammar, syntax and idiom. John Dryden (1631–1700) wrote in his preface to the translation anthology "Sylvae": A translation that meets the criterion of fidelity (faithfulness) is said to be "faithful"; a translation that meets the criterion of transparency, "idiomatic". Depending on the given translation, the two qualities may not be mutually exclusive. The criteria for judging the fidelity of a translation vary according to the subject, type and use of the text, its literary qualities, its social or historical context, etc. The criteria for judging the transparency of a translation appear more straightforward: an unidiomatic translation "sounds wrong"; and, in the extreme case of word-for-word translations generated by many machine-translation systems, often results in patent nonsense. Nevertheless, in certain contexts a translator may consciously seek to produce a literal translation. Translators of literary, religious, or historic texts often adhere as closely as possible to the source text, stretching the limits of the target language to produce an unidiomatic text. Also, a translator may adopt expressions from the source language in order to provide "local color". While current Western translation practice is dominated by the dual concepts of "fidelity" and "transparency", this has not always been the case. There have been periods, especially in pre-Classical Rome and in the 18th century, when many translators stepped beyond the bounds of translation proper into the realm of "adaptation". Adapted translation retains currency in some non-Western traditions. The Indian epic, the "Ramayana", appears in many versions in the various Indian languages, and the stories are different in each. Similar examples are to be found in medieval Christian literature, which adjusted the text to local customs and mores.  Many non-transparent-translation theories draw on concepts from German Romanticism, the most obvious influence being the German theologian and philosopher Friedrich Schleiermacher. In his seminal lecture "On the Different Methods of Translation" (1813) he distinguished between translation methods that move "the writer toward [the reader]", i.e., transparency, and those that move the "reader toward [the author]", i.e., an extreme fidelity to the foreignness of the source text. Schleiermacher favored the latter approach; he was motivated, however, not so much by a desire to embrace the foreign, as by a nationalist desire to oppose France's cultural domination and to promote German literature.  In recent decades, prominent advocates of such "non-transparent" translation have included the French scholar Antoine Berman, who identified twelve deforming tendencies inherent in most prose translations, and the American theorist Lawrence Venuti, who has called on translators to apply "foreignizing" rather than domesticating translation strategies.

Translators.

Competent translators show the following attributes:  A competent translator is not only bilingual but bicultural. A language is not merely a collection of words and of rules of grammar and syntax for generating sentences, but also a vast interconnecting system of connotations and cultural references whose mastery, writes linguist Mario Pei, "comes close to being a lifetime job." The complexity of the translator's task cannot be overstated; one author suggests that becoming an accomplished translator—after having already acquired a good basic knowledge of both languages and cultures—may require a minimum of ten years' experience. Viewed in this light, it is a serious misconception to assume that a person who has fair fluency in two languages will, by virtue of that fact alone, be consistently competent to translate between them.  The translator's role in relation to a text has been compared to that of an artist, e.g., a musician or actor, who interprets a work of art. Translation, like other human activities, entails making choices, and choice implies interpretation. Mark Polizzotti writes: "A good translation offers not a reproduction of the work but an interpretation, a re-representation, just as the performance of a play or a sonata is a representation of the script or the score, one among many possible representations."  The English-language novelist Joseph Conrad, whose writings Zdzisław Najder has described as verging on "auto-translation" from Conrad's Polish and French linguistic personae, advised his niece and Polish translator Aniela Zagórska: "[D]on't trouble to be too scrupulous... I may tell you (in French) that in my opinion "il vaut mieux interpréter que traduire" [it is better to interpret than to translate]..."Il s'agit donc de trouver les équivalents. Et là, ma chère, je vous prie laissez vous guider plutôt par votre tempérament que par une conscience sévère..." [It is, then, a question of finding the equivalent expressions. And there, my dear, I beg you to let yourself be guided more by your temperament than by a strict conscience...]" Conrad advised another translator that the prime requisite for a good translation is that it be "idiomatic". "For in the idiom is the "clearness" of a language and the language's force and its picturesqueness—by which last I mean the picture-producing power of arranged words." Conrad thought C.K. Scott Moncrieff's English translation of Marcel Proust's "À la recherche du temps perdu" ("In Search of Lost Time"—or, in Scott Moncrieff's rendering, "Remembrance of Things Past") to be preferable to the French original.  The necessity of making choices, and therefore of interpretation, in translating (and in other fields of human endeavor) stems from the ambiguity that subjectively pervades the universe. Part of the ambiguity, for a translator, involves the structure of human language. Psychologist and neural scientist Gary Marcus notes that "virtually every sentence [that people generate] is ambiguous, often in multiple ways. Our brain is so good at comprehending language that we do not usually notice." An example of linguistic ambiguity is the "pronoun disambiguation problem" ("PDP"): a machine has no way of determining to whom or what a pronoun in a sentence—such as "he", "she" or "it"—refers. Such disambiguation is not infallible by a human, either.  Ambiguity is a concern to both translators and, as the writings of poet and literary critic William Empson have demonstrated, to literary critics. Ambiguity may be desirable, indeed essential, in poetry and diplomacy; it can be more problematic in ordinary prose.  A translator is faced with two contradictory tasks: when translating, strive for omniscience; when reviewing the resulting translation, assume (the naive reader's) ignorance.  Translators may render only parts of the original text, provided that they inform readers of that action. But a translator should not assume the role of censor and surreptitiously delete or bowdlerize passages merely to please a political or moral interest.  Translating has served as a school of writing for many an author, much as the copying of masterworks of painting has schooled many a novice painter. A translator who can competently render an author's thoughts into the translator's own language, should certainly be able to adequately render, in his own language, any thoughts of his own. Translating (like analytic philosophy) compels precise analysis of language elements and of their usage. In 1946 the poet Ezra Pound, then at St. Elizabeth's Hospital, in Washington, D.C., advised a visitor, the 18-year-old beginning poet W.S. Merwin: "The work of translation is the best teacher you'll ever have." Merwin, translator-poet who took Pound's advice to heart, writes of translation as an "impossible, unfinishable" art.  Translators, including monks who spread Buddhist texts in East Asia, and the early modern European translators of the Bible, in the course of their work have shaped the very languages into which they have translated. They have acted as bridges for conveying knowledge between cultures; and along with ideas, they have imported from the source languages, into their own languages, loanwords and calques of grammatical structures, idioms, and vocabulary.

Machine translation.

Machine translation (MT) is a process whereby a computer program analyzes a source text and, in principle, produces a target text without human intervention. In reality, however, machine translation typically does involve human intervention, in the form of pre-editing and post-editing. With proper terminology work, with preparation of the source text for machine translation (pre-editing), and with reworking of the machine translation by a human translator (post-editing), commercial machine-translation tools can produce useful results, especially if the machine-translation system is integrated with a translation-memory or globalization-management system.  Unedited machine translation is publicly available through tools on the Internet such as Google Translate, Babel Fish, Babylon, and StarDict. These produce rough translations that, under favorable circumstances, "give the gist" of the source text. With the Internet, translation software can help non-native-speaking individuals understand web pages published in other languages. Whole-page-translation tools are of limited utility, however, since they offer only a limited potential understanding of the original author's intent and context; translated pages tend to be more erroneously humorous and confusing than enlightening.  Interactive

Literary translation.

Translation of literary works (novels, short stories, plays, poems, etc.) is considered a literary pursuit in its own right. Notable in Canadian literature "specifically" as translators are figures such as Sheila Fischman, Robert Dickson, and Linda Gaboriau; and the Canadian Governor General's Awards annually present prizes for the best English-to-French and French-to-English literary translations.  Other writers, among many who have made a name for themselves as literary translators, include Vasily Zhukovsky, Tadeusz Boy-Żeleński, Vladimir Nabokov, Jorge Luis Borges, Robert Stiller, Lydia Davis, Haruki Murakami, Achy Obejas, and Jhumpa Lahiri.  In the 2010s a substantial gender imbalance was noted in literary translation into English, with far more male writers being translated than women writers. In 2014 Meytal Radzinski launched the "Women in Translation" campaign to address this.

History.

The first important translation in the West was that of the Septuagint, a collection of Jewish Scriptures translated into early Koine Greek in Alexandria between the 3rd and 1st centuries BCE. The dispersed Jews had forgotten their ancestral language and needed Greek versions (translations) of their Scriptures.  Throughout the Middle Ages, Latin was the "lingua franca" of the western learned world. The 9th-century Alfred the Great, king of Wessex in England, was far ahead of his time in commissioning vernacular Anglo-Saxon translations of Bede's "Ecclesiastical History" and Boethius' "Consolation of Philosophy". Meanwhile, the Christian Church frowned on even partial adaptations of St. Jerome's "Vulgate" of c. 384 CE, the standard Latin "Bible".  In Asia, the spread of Buddhism led to large-scale ongoing translation efforts spanning well over a thousand years. The Tangut Empire was especially efficient in such efforts; exploiting the then newly invented block printing, and with the full support of the government (contemporary sources describe the Emperor and his mother personally contributing to

Modern translation.

As a language evolves, texts in an earlier version of the language—original texts, or old translations—may become difficult for modern readers to understand. Such a text may therefore be translated into more modern language, producing a "modern translation" (e.g., a "modern English translation" or "modernized translation").  Such modern rendering is applied either to literature from classical languages such as Latin or Greek, notably to the Bible (see "Modern English Bible translations"), or to literature from an earlier stage of the same language, as with the works of William Shakespeare (which are largely understandable by a modern audience, though with some difficulty) or with Geoffrey Chaucer's Middle-English "Canterbury Tales" (which is understandable to most modern readers only through

Poetry.

Views on the possibility of satisfactorily translating poetry show a broad spectrum, depending largely on the degree of latitude to be granted the translator in regard to a poem's formal features (rhythm, rhyme, verse form, etc.). Douglas Hofstadter, in his 1997 book, "Le Ton beau de Marot", argued that a good translation of a poem must convey as much as possible not only of its literal meaning but also of its form and structure (meter, rhyme or alliteration scheme, etc.).  The

Book titles.

Book-title translations can be either descriptive or symbolic. Descriptive book titles, for example Antoine de Saint-Exupéry's "Le Petit Prince" (The Little Prince), are meant to be informative, and can name the protagonist, and indicate the theme of the book. An example of

Plays.

The translation of plays poses many problems such as the added element of actors, speech duration, translation literalness, and the relationship between the arts of drama and acting. Successful play translators are able to create language that allows the actor and the playwright to work together effectively. Play translators must also take into account

Chinese literature.

In translating Chinese literature, translators struggle to find true fidelity in translating into the target language. In "The Poem Behind the Poem", Barnstone argues that poetry "can't be made to sing through a mathematics that doesn't factor in the creativity of the translator".  A notable piece of work translated into English is the "Wen Xuan", an anthology representative of major works of Chinese literature. Translating this

Sung texts.

Translation of a text that is sung in vocal music for the purpose of singing in another language—sometimes called "singing translation"—is closely linked to translation of poetry because most vocal music, at least in the Western tradition, is set to verse, especially verse in regular patterns with rhyme. (Since the late 19th century, musical setting of prose and free verse has also been practiced in some art music, though popular music tends to remain conservative in its retention of stanzaic forms with or without refrains.) A rudimentary example of translating poetry for singing is church hymns, such as the German chorales translated into English by Catherine Winkworth.  Translation of sung texts is generally much more restrictive than translation of poetry, because in the former there is little or no freedom to choose between a versified translation and a translation that dispenses with verse structure. One might modify or omit rhyme in a singing translation, but the assignment of syllables to specific notes in the

Religious texts.

An important role in history has been played by translation of religious texts. Such translations may be influenced by tension between the text and the religious values the translators wish to convey. For example, Buddhist monks who translated the Indian sutras into Chinese occasionally adjusted their translations to better reflect China's distinct culture, emphasizing notions such as filial piety.  One of the first recorded instances of translation in the West was the rendering of the Old Testament into Greek in the 3rd century BCE. The translation is known as the "Septuagint", a name that refers to the supposedly seventy translators (seventy-two, in some versions) who were commissioned to translate the Bible at Alexandria, Egypt. According to legend, each translator worked in solitary confinement in his own cell, and, according to legend, all seventy versions proved identical. The "Septuagint" became the source text for later translations into many languages, including Latin, Coptic, Armenian and Georgian.  Still considered one of the greatest translators in history, for having rendered the "Bible" into Latin, is Jerome (347–420 C.E.), the patron saint of translators. For centuries the Roman Catholic Church used his translation (known as the

Science fiction.

Science fiction being a genre with a recognizable set of conventions and literary genealogies, in which language often includes neologisms, neosemes, and invented languages, techno-scientific and pseudoscientific vocabulary, and fictional representation of the translation process, the translation of science-fiction texts involves specific concerns. The science-fiction translator tends to acquire specific competences and assume a distinctive publishing and cultural agency. As in the case of other mass-fiction genres, this professional specialization and role

Technical translation.

Technical translation renders documents such as manuals, instruction sheets, internal memos, minutes, financial reports, and other documents for a limited audience (who are directly affected by the document) and whose useful life is often limited. Thus, a user guide for a particular model of refrigerator is useful only for the owner of the refrigerator, and will remain useful only as long as that refrigerator model is in use. Similarly, software documentation generally pertains to a particular software, whose applications are used only by a certain class of users.

Translation is the communication of the meaning of a source language text by means of an equivalent target language text. The English language draws a terminological distinction (which does not exist in every language) between "translating" (a written text) and "interpreting" (oral or signed communication between users of different languages); under this distinction, translation can begin only after the appearance of writing within a language community.

Unter Übersetzung versteht man in der Sprachwissenschaft einerseits die Übertragung der Bedeutung eines (meist schriftlich) fixierten Textes in einer Ausgangssprache in eine Zielsprache; anderseits versteht man darunter das Ergebnis dieses Vorgangs.


Overview.

Didactics is a theory of teaching, and in a wider sense, a theory and practical application of teaching and learning. In demarcation from "mathetics" (the science of learning), didactics refers only to the science of teaching.  This theory might be contrasted with open learning, also known as experiential learning, in which people can learn by themselves, in an unstructured manner, on topics of interest.  The theory of didactic learning methods focuses on the baseline knowledge students possess and seeks to improve upon and convey this information. It also refers to the foundation or starting point in a lesson plan, where the overall goal is knowledge. A teacher or educator functions in this role as an authoritative figure, but also as both a guide and a resource for students.  Didactics or the didactic method have different connotations in continental Europe and English-speaking countries. For example in the Anglo-Saxon tradition, the Oxford dictionary defines didactics as a particularly moral instruction. Following that, the didactic method still carries the original meaning of teaching moral contents, and is therefore associated with unfavourable views opposed to the teachings of a true art or science. Didacticism was indeed the cultural origin of the didactic method but refers within its narrow context usually pejoratively to the use of language to a doctrinal end. The interpretation of these opposing views are theorised to be the result of a differential cultural development in the 19th century when Great Britain and its former colonies went through a renewal and increased cultural distancing from continental Europe. It was particularly the later appearance of Romanticism and Aestheticism in the Anglo-Saxon world which offered these negative and limiting views of the didactic method. On the other hand, in continental Europe those moralising aspects of didactics were removed earlier by cultural representatives of the age of enlightenment, such as Voltaire, Rousseau, and later specifically related to teaching by Johann Heinrich Pestalozzi.  The consequences of these cultural differences then created two main didactic traditions: The Anglo-Saxon tradition of curriculum studies on one side and the Continental and North European tradition of didactics on the other. Still today, the science of didactics carries much less weight in much of the English-speaking world.  With the advent of globalisation at the beginning of the 20th century, however, the arguments for such relative philosophical aspects in the methods of teaching started to diminish somewhat. It is therefore possible to categorise didactics and pedagogy as a general analytic theory on three levels:

Didactic teaching.

Didactic method provides students with the required theoretical knowledge. It is an effective method used to teach students who are unable to organize their work and depend on the teachers for instructions. It is also used to teach basic skills of reading and writing. The teacher or the literate is the source of knowledge and the knowledge is transmitted to the students through didactic method.  Didactic Teaching materials:  The Montessori school had preplanned teaching (Didactic) materials designed, to develop practical, sensory, and formal skills. Lacing and buttoning frames, weights, and packet to be identified by their sound or smell. Because they direct learning in the prepared environment, Montessori educators are called directress rather than teachers.  In Brazil, there has been for more than 80 years the government program called PNLD (National Program of Didactic Book). This program seeks to provide basic education schools with didactic and pedagogical records, expanding access to the book and democratizing access to sources of information and culture. Textbooks, in many cases, are the only sources of information that poor children and young people have access to in a poor country like Brazil. These books are also valuable support to teachers, offering modern learning methodologies and updated concepts and content in the most diverse disciplines.  Source: https://www.fnde.gov.br/acesso-a-informacao/institucional/area-de-imprensa/noticias/item/11015-em-comemoracao-aos-80-anos-mec-lanca-concurso-literario https://www.fnde.gov.br/programas/programas-do-livro

Method of teaching.

In didactic method of teaching, the teacher gives instructions to the students and the students are mostly passive listeners. It is a teacher-centered method of teaching and is content oriented. The content or knowledge of the teacher is not questioned.  The process of teaching involves the teacher who gives instructions, commands, delivers content, and provides necessary information. The pupil activity involves listening and memorization of the content. In the modern education system, lecture method which is one of the most commonly used methods is a form of didactic teaching.

Limitations.

Though the didactic method has been given importance in several schools, it does not satisfy the needs and interests of all students. It can be tedious for students to listen to the possible lectures. There is minimum interaction between the students and the teachers. Learning which also involves motivating the students to develop an interest towards the subject may not be satisfied through this teaching method.

A didactic method ( "didáskein", "to teach") is a teaching method that follows a consistent scientific approach or educational style to present information to students. The didactic method of instruction is often contrasted with dialectics and the Socratic method; the term can also be used to refer to a specific didactic method, as for instance constructivist didactics.

Die Didaktik (von ) ist die „Kunst“ und die „Wissenschaft“ des Lernens und Lehrens. Sie ist eine zentrale Disziplin der Pädagogik und gehört neben der fachlichen Ausbildung zur Qualifizierung in der wissenschaftlichen Lehrerbildung.