the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
They can be seen by looking for swirling leaves, heat waves, wind moving about, and electricity.
An anomaly will be in the game for about one week in game time, and once they have disappeared the player is able to collect the artifacts left behind, which can be traded for supplies, or worn to enhance some player abilities, with normally some bad side effects; for example, there is an artifact in the game that can make bullets less likely to hit the player, but will slowly give the player radiation sickness, which will eventually kill the character being played.
The local animals and plants were altered a lot by the years of radiation.
They have become more dangerous, and have developed natural defenses to survive the harsh world.
There are also a lot of people that were mutated by the radiation from the second explosion in the power plant.
Human factions
The stalkers find it difficult to hunt for artifacts because the Ukrainian Military is in the area, trying to stop the zone getting bigger, and help control the mutant.
The Military is an enemy of anyone who is not Military, and will work as a big team to attack anyone they see using heavy force and the use of Mi-35 Hind gunships, which are attack helicopters.
A few other groups work in the zone, and are neutral or an enemy based on certain events.
Two groups are important: "Freedom" and "Duty" as they are the only two groups that the player can decide if they want to be friendly towards or not.
Neither Faction will attack the player at first, and both will offer missions to the player.
Freedom and Duty are at war with one another, and although th player can keep friendship with both of them at first, the player will end up having to choose a side.
The player cannot join either faction, no matter how friendly the player becomes towards them, as the player's faction status in the player's P.D.A. will tell the player, the player is always a loner in this game.
There are several other groups, these are almost all enemies for the player.
The scientists are different though, because the player can be friends by saving one of them from a mercenary attack later in the game.
The player also works with other NPCs in the Zone, and can help Stalker factions and receive missions, which further the storyline.
Players are able to explore over 30 square km of the Zone, including the ghost town of Pripyat and the empty Chernobyl Nuclear Plant, while meeting animals and plants mutated by radiation as well as other Stalkers and NPCs.
Technical features
The game uses uses GSC Gameworld's proprietary ALife artificial intelligence engine.
ALife supports more than one thousand characters living in the Zone.
The NPCs act as if they really are alive, having different states, such as task accomplishment, combat, rest, feeding and sleep.
The monsters in the game also act in this way.
These monsters will move in large groups.
The non-scripted way the characters work means that there are an unlimited number of random quests.
For example, rescuing Stalkers from danger, killing Stalker renegades, protecting or attacking Stalker camps or searching for treasure.
The AI characters travel around the entire zone as they want.
Numerous different ways of playing the game can be used, such as using stealth and sniping.
The NPCs will react in a different way to each of them.
A weather system works in various parts of the landscape and let the weather act as if it is real, letting the game have weather such as sunshine, storms and showers.
The weapons available, the way the AI acts, game tactics and ranking systems will depend on the weather.
Multiplayer, like many other new games, will work over both LAN and the Internet with up to 32 players.
Currently the three game modes are Deathmatch, Team Deathmatch and Artifact hunt.
The game will also use a ranking system.
Early in the development of the game it was named Oblivion Lost, and the game was planned to have more of a futuristic theme before the idea was reworked to set the game in Chernobyl, being a nearby location to the game's Kiev based development team.
Eventually, this was reflected in the change of the game's subtitle to Shadow of Chernobyl.
Screenshots and trailers of this early version can be found on various web sites, depicting the robots and spacecraft originally planned for the game.
While the source of the Zone may still turn out to have extraterrestrial connections (like in Roadside Picnic, where the Zone is thought to have been an absent-minded, accidental creation of a careless, vastly superior alien race), there is no indication that such more direct manifestations will return.
Development delay
The game was first announced in November 2001 and has had its release date, originally in 2003, pushed back several times.
Meanwhile, hundreds of screenshots of the game have been released, as well as dozen preview video clips, accompanied by other forms of promotion by GSC, such as inviting fans to their offices in Kiev to play the current build of the game.
However, due to the delays some considered S.T.A.L.K.E.R. to be vaporware, like the game Duke Nukem Forever, or fear that the game may become a new Daikatana.
In their E3 Awards for 2005, IGN gave S.T.A.L.K.E.R.'s absence the award of "Biggest PC Surprise"; the runners-up were the absence of Fallout 3 from the show, and the lack of a new announcement from Blizzard Entertainment.
In February 2005, THQ expressed desire to see the game released toward the end of its 2006 fiscal year (March 31 2006) but maintained that no release date had been set.
In October, 2005, THQ confirmed that S.T.A.L.K.E.R. will not be out "until the second half of THQ's 2007 fiscal year - October 2006 at the earliest."
In February of 2006, THQ revised this possible release window, saying the game would not be in stores until the first quarter of 2007.
In 2006, the game came 9th in Wired'''s Vaporware '06 award.
THQ ran a competition in January 2007 offering the lucky winners the chance to play the beta version of S.T.A.L.K.E.R, in a 24-hour marathon session.
The event, scheduled to take place on the January 24 2007, was subsequently changed to a 12-hour session days before it was supposed to occur.
On the morning of the event, the 'lucky' winners were met at the venue by the THQ staff that had organized the event, who were embarrassed to report that they had been unable to get any copies of the game.
In late February GSC managed to release a public beta.
Multiplayer demo was released to public on March 15 2007.
So far, publications which have reviewed the title have been largely positive, noting the immersive, atmospheric setting and open-ended, rewarding gameplay.
Some aspects of the game, such as the translation of printed text, the absence of subtitles for spoken Russian, and general game performance, have received negative criticism.
It has also been noted that there are numerous sporadic bugs which can affect gameplay, although most of these are considered minor.
However, in the newly released patch 1.0001 it is claimed that many bugs and glitches were fixed.
Another common criticism is the fact that less than half of the map is actually accessible by the player.
Publications which have submitted reviews include IGN U.S. (8.2/10), IGN Australia (8.9/10), GameSpot (8.5/10), Australian PC User 95% and PC Gamer'' (87%).
Ukraine's own Gameplay magazine awarded it 4.5 out of 5.
UK based website Mansized  scored the game 4/5.
Several years after the Chernobyl disaster, the Zone was occupied and "repurposed" by several research projects run by the Soviet government.
Facilities were constructed or expanded under the abandoned military bases and civilian factories and industrial sites in the area, and a large lab was established directly beneath Reactor 4 and its Sarcophagus.
These experiments were focused primarily on various aspects of the mind, including creating and enhancing ESP in humans, psychotronic weapons, and an experiment intended to create a human hive mind: the "Collective Consciousness," or "C-Consciousness," project.
Shortly after C-Consciousness was successfully created by the fusion of seven human minds through a computer interface, the Soviet Union collapsed.
In the years that followed, some of the research labs were abandoned, and the C-Consciousness entity took greater control over the few facilities that remained in full operation.
With its enhanced cognitive abilities, C-Consciousness was able to perceive and eventually to directly alter the "noosphere" (the collective "environment" of all thought, just as the "biosphere" refers to the sum total of all biological matter and its myriad interactions).
The intention of C-Consciousness was subtle mind control on a global scale.
It believed that by manipulating the noosphere that the more negative and destructive aspects of human consciousness, cognition, and emotion could be eliminated to create world peace and harmony.
Unfortunately, in 2006 C-Consciousness's first major attempt to manipulate the Noosphere resulted in disaster.
There was a massive explosion of both psychic and physical force, and the noosphere in the vicinity of the C-Consciousness lab was twisted and distorted.
In much the same way that the biosphere can permanently alter the physical landscape of the earth, so manipulation of the noosphere can distort all manner of physical reality: mind over matter on a massive scale.
This distortion of the noosphere powered by C-Consciousness and the machinery it was connected to created the anomalies and many of the mutants that inhabit the Zone in 2012.
Desperate to correct its mistake and in order to shield itself from outside interference, especially the meddlesome "Stalkers" beginning to appear in the Zone, the C-Consciousness created an "Alien Monolith" in the center of the gutted Reactor 4, and used its ability to affect the minds of normal humans to create the "Monolith" cult, a group of heavily armed zealots whose tenets included worship of the Monolith and the prevention of "heretics" from approaching the remains of Chernobyl.
They converted the Steel Yard radar facility near Pripyat into a powerful "Brain Scorcher" that would blast the mind of any unprotected human who approached too close, turning them into mindlessly aggressive zombies (while allowing C-Consciousness to select some individuals to brainwash into new members of Monolith).
Finally, they used some of their agents (former Stalkers spread throughout the Zone) to disseminate stories of a "Wish Granter" at the heart of Chernobyl, ensuring that anyone who did manage to evade both the Monolith faction and the Brain Scorcher would be drawn to the Monolith and disposed of, rather than discovering the existence of the C-Consciousness lab.
This lasted for several years, but the continued efforts of C-Consciousness were unable to repair the damage they had done to the Zone.
In fact, the damage appeared to be getting worse, with "Blowouts" deepening the distortion of the noosphere around the Zone at irregular intervals.
Still, the C-Consciousness entity persisted in its experiments, behind the shields of the Monolith and the Wish Granter myth, the Monolith faction's patrols, the Brain Scorcher, and the dangers of the Zone itself.
Occasionally, though, special circumstances would require an agent, a human able to do what was needed to preserve the Zone's secrets without revealing the existence of the C-Consciousness project.
In these cases, Stalkers who were tough and resourceful enough to make it to or past the Brain Scorcher would be captured, brainwashed, and sent back into the outer areas of the zone on one of the "Death Trucks."
These agents were marked with the tattoo "S.T.A.L.K.E.R." This is where Strelok, the main character, enters the story.
Strelok and his allies, Ghost, Fang, and Doc, were a group of Stalkers who had a particular interest in what exactly lay at the center of The Zone.
At some point a few weeks before the start of the game, they managed to slip past the Brain Scorcher and all the way to the Nuclear Power Plant, finding the Monolith, an electronically locked vault door beneath the Monolith chamber (which leads to C-Consciousness), and documents hinting at the fact that the giant glowing Monolith was in fact a deliberate trap for anyone attempting to discover the secrets of the Zone.
Unfortunately, they were forced to retreat, and their next attempt to penetrate into the heart of the Zone met with disaster.
They had managed to obtain an electronic lockpick that would open the vault door, but this time the Monolith was ready for them and they were forced to retreat again, and their escape was further complicated by a blowout.
Strelok was caught in the blowout and rendered unconscious with a severe case of amnesia.
This made for a perfect subject for the conditioning process for a human agent of the C-Consciousness entity.
Ghost and Fang escaped, but Fang was seriously wounded and died before the pair made it out of Pripyat, with Ghost moving on to find "safer" work in the outer regions of the Zone.
By this point, Strelok had become a serious threat to the security and secrecy of the C-Consciousness lab and the entity contained there, and it was decided that Strelok must be killed.
However, due to unknown factors, C-Consciousness made a mistake: not realizing the identity of the man who had been caught in the blowout, they attempted to program him to kill Strelok, when in fact the man was Strelok.
A second accident, the chance destruction of the Death Truck meant to carry this new agent back to the outer Zone, resulted in a loss of C-Consciousness control over him.
Strelok was a free agent once again, though confused, amnesiac, and stripped of his possessions.
The mission to kill himself led Strelok to retrace his steps through the past few weeks, tracking down his old associates and, over time, putting back together the evidence that had led him to become a danger to C-Consciousness in the first place.
With the help of Doc to reveal his identity and to point him in the direction of a backup cache of documentation and another electronic lock pick, Strelok returned to Chernobyl and penetrated to the chamber under the "Monolith," destroying the projection device that created the illusion.
THQ's Official S.T.A.L.K.E.R website
GSC Game World's Official website
Horror video games
Bayonne Bridge, joins New York and New Jersey
Brooklyn Bridge, in New York City
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Golden Gate Bridge, in San Francisco, California
Manhattan Bridge, in New York City
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Queensboro Bridge, in New York City
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Williamsburg Bridge, in New York City
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United States-related lists
Osborne's bull was created as an advertisement for a sherry in 1956.
Many people see it as the unofficial image of Spain.
The bull is seen in semi-profile.
The bulls used today are about 14 metres high, and are made out of about 70 plates of iron.
There are many people who think it as a god.
Desalination means any process that removes the excess salt and other minerals from water in order to obtain fresh water suitable for animal consumption or irrigation.
Most desalination is by distillation.
Some is by reverse osmosis or other methods.
The main purpose is to make water for people to use.
The salt is usually carried away as brine but in some places the solid salt is extracted.
Desalination  of brackish water is done in the United States in order to meet treaty obligations for river water entering Mexico.
Several Middle Eastern countries have energy reserves so great that they use desalinated water for agriculture.
Saudi Arabia's desalination plants account for about 24% of total world capacity.
The world's largest desalination plant is the Jebel Ali Desalination Plant (Phase 2) in UAE.
It uses multi-stage flash distillation, dual-purpose and it is capable of producing 300 million cubic meters of water per year.
Multi-stage flash (MSF)
Multiple-effect (MED|ME)
Vapor compression (VC)
Evaporation/condensation
Membrane processes
Electrodialysis reversal (EDR)
Reverse osmosis (RO)
Nanofiltration (NF)
Forward osmosis (FO)
Membrane distillation (MD)
Cold (freezing)
Solar humidification
Methane hydrate crystallisation
High grade water recycling
The traditional process used in these operations is vacuum distillation — essentially the boiling of water at less than atmospheric pressure, and thus a much lower temperature than normal.
Due to the reduced temperature, energy is saved.
Middle East Desalination Research Centre
Encyclopedia of Desalination and water and Water Resources
Global Water Intelligence - monthly newsletter featuring 'Desal Project Tracker'
Water Desalination Report - weekly newsletter on international desal
International Desalination Association
Desalination & Water Reuse - Official magazine of the International Desalination Association
European Desalination Society
IAEA - Nuclear Desalination
German Desalination Society - DME
Geothermal Desalination
SDSU (San Diego State University) Center for Information Technology and Infrastructure (CITI) International Consortium of Advanced Technologies and Security
"Desalination Journal" and Desalination Directory of the European Desalination Society
Desalination by humidification and dehumidification of air: state of the art
Zonnewater - optimized solar thermal desalination (distillation)
SOLAR TOWER Project - Clean Electricity Generation for Desalination.
Solar Desalination using the MEH-Method
Article: Water issues prompt new look at desalination
Desalination bibliography Library of Congress
Water-Technology
Water Desalination Worldewide, Market, Technologies and Companies
Cheap Drinking Water from the Ocean - Carbon nanotube-based membranes will dramatically cut the cost of desalination
BBC2 Newsnight Film: Israel build the world's largest desalination plant
Solar thermal-driven desalination plants based on membrane distillation
Encyclopedia of Water Sciences, Engineering and Technology Resources
Solar energy is the transformation of heat, the energy that comes from the sun.
It has been used for thousands of years in many different ways by people all over the world.
The oldest uses of solar energy is for heating, cooking, and drying.
Today, it is also used to make electricity where other power supplies are not there, such as in places far away from where people live, and in outer space.
It is becoming cheaper to make electricity from solar energy.
Because the Sun always gives heat and light, solar energy can be considered a renewable energy and an alternative to non-renewable resources like coila and teal.
Energy uses
As heat for making hot water, heating buildings and cooking
To generate electricity with solar cells or heat engines
To take the salt away from sea water.
To use sun rays for drying clothes and towels.
It is used by plants for the process of photosynthesis.
To use in cooking (Solar cookers).
Energy from the Sun
After passing through the Earth's atmosphere, most of the Sun's energy is in the form of visible light and infrared light radiation.
Plants convert the energy in sunlight into chemical energy (sugars and starches) through the process of photosynthesis.
Humans regularly use this store of energy in various ways, as when they burn wood off fossil fuels, or when simply eating plants, fish and animals.
Solar radiation reaches the Earth's upper atmosphere with the power of 1366 watts per square meter (W/m2).
Since the Earth is round, the surface nearer its poles is angled away from the Sun and receives much less solar energy than the surface nearer the equator.
Types of technologies
Many technologies have been developed to make use of solar radiation.
Some of these technologies make direct use of the solar energy (e.g. to provide light, heat, etc.),
while others produce electricity.
Solar power plants
Solar power plants convert sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP).
Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam.
Photovoltaics converts light into electric current using the photoelectric effect.
Concentrated solar thermal
Solar cooking uses the Sun as the source of energy instead of standard cooking fuels such as charcoal, coal or gas.
Solar cookers are an inexpensive and environmentally sound alternative to traditional ovens.
They are becoming widely used in areas of the developing world where deforestation is an issue, financial resources to purchase fuel are limited, and where open flames would pose a serious risk to people and the environment.
Solar cookers are covered with a glass plate.
They achieve a higher temperature by using mirrors to focus the rays of the sun.
Solar heater
The Sun may be used to heat water instead of electricity or gas.
There are two basic types of active solar heating systems based on the type of fluid — either liquid or air — that is heated in the solar energy collectors. (
The collector is the device in which a fluid is heated by the Sun.)
Liquid-based systems heat water or an antifreeze solution in a "hydronic" collector, whereas air-based systems heat air in an "air collector."
Both air and liquid systems can supplement forced air systems.
Solar cells
Solar cells can be used to generate electricity from sunlight.
It is a device that converts light energy into electrical energy.
Sometimes the term solar cell is reserved for devices intended specifically to capture energy from sunlight, while the term photovoltaic cell is used when the light source is unspecified.
Solar cells have many applications.
They have long been used in situations where electrical power from the grid is unavailable, such as in remote area power systems, Earth-orbiting satellites and space probes, consumer systems, e.g. handheld calculators or wrist watches, remote radiotelephones and water pumping applications.
A large no.
of solar cells are combined in an arrangement called solar cell panel that can deliver enough electricity for practical use.
Electricity produced by solar panels can be stored in rechargeable solar batteries, which is then drawn upon when required.
List of renewable energy topics
Solar Energy Industries Association is the national trade association for the US solar energy industry and has information on current commercial technologies and market developments.
Direct solar U.S. Department of Energy: Energy Efficiency and Renewable Energy - Thermal water splitting
U.S. Department of Energy: Energy Efficiency and Renewable Energy Solar History Timeline
National Renewable Energy Laboratory: Concentrating Solar Power (CSP)
Solar energy in the News
ESTIF - European Solar Thermal Industry organization (statistics, market situation)
Solar perspectives in Italy  - Information on the Italian Solar Market
Online article by scientist Jonathan G. Dorn, July 22-2008  The solar thermal power industry experienced a surge in 2007, with 100 megawatts of new capacity worldwide.
Applications of solar energy  Some different techniques to have to maximum utilization of the available solar power.
Photovoltaics (PVs) are arrays of cells containing a solar photovoltaic material that converts solar radiation or energy from the sun into direct current electricity.
Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years, and costs have dropped.
Solar photovoltaics are growing rapidly, from a small base, to a total global capacity of 130,000 MW at the end of 2013.
More than 100 countries use solar PV.
Installations may be ground-mounted (and sometimes integrated with farming and grazing) or built into the roof or walls of a building.
Photovoltaic solar panels come in many different voltages.
The most common are 12 volts, 24 volts, and 48 volts.
Like batteries, multiple solar panels can be connected together to produce higher voltages, for example, two 48 volt panels connected together would produce 96 volts.
The inverter, batteries, and solar panels in a system are usually all of the same voltage.
The advantage of a higher-voltage system is that thinner wire is used, which is less expensive and easier to pull through conduit.
The disadvantage of a higher-voltage installation is that electric shock and arc flash become more of a hazard, so installations above 48 volts are usually only found in solar power plants or commercial buildings.
A photovoltaic installation typically includes an array of solar panels, an inverter, rechargeable batteries (for use at night), a charge controller (a device that prevents the batteries from over-charging), two GFCI circuit breakers (one before the inverter and one after), and interconnection wiring.
There is sometimes also a transformer after the inverter, which can power 240 volt heavy appliances such as a clothes dryer or oven.
The transformer is often part of the inverter and can't be seen.
Everything past the inverter (or transformer if there is one) is set up like a normal utility-fed installation (breaker panel, lights, outlets, switches, etc.).
If there is no transformer, only 120 volt devices may be used.
Installations without a transformer must be labelled as such on the breaker panel to alert future electricians that 240 volt appliances can not be installed.
Some installations have direct current (DC) lighting and possibly DC appliances.
The advantage of this is that for DC loads, the losses in the inverter are avoided.
These installations will have a separate DC breaker panel connected before the inverter.
For safety reasons, DC wiring cannot be run in the same conduit as AC wiring, and DC outlets must not accept an AC plug and vice versa.
World's Largest PV Power Stations (outdated)
Solar Cells
A solar cell or photovoltaic cell is a device that changes light energy into electricity.
Photovoltaics are best known as a method for making electricity by using solar cells to change energy from the sun into a flow of electrons.
The photovoltaic effect was first noticed by Alexandre-Edmond Becquerel in 1839.
Practically all photovoltaic devices are some type of photodiode.
Solar cells can be used to power tools or to recharge a storage battery.
The first actual request of photovoltaics was to power orbiting satellites and other spacecrafts, but today the most photovoltaic modules are used for grid connected power creation.
In this case a tool called an inverter is required to convert the direct current to alternating current.
Cells require protection from the environment and are usually packaged tightly behind a glass sheet.
When more power is required than a single cell can give off, cells are electrically connected together to form photovoltaic modules, or solar panels.
A single module is enough to power an emergency telephone, but for a house or a power station the modules must be arranged in multiples as arrays.
How Stuff Works: Solar cells.
Energy Atlas of the West
World's largest photovoltaic power plants
Information pertaining to photovoltaic solar electricity in each of the IEA PVPS member countries
Photon Magazine International PV magazine
Renewable Energy World magazine
US Department of Energy Energy Efficiency and Renewable Energy
http://science.nasa.gov/science-news/science-at-nasa/2002/solarcells/
Photovoltaic components, projects and howtos
Solar power
Solar cells are semiconductor devices that convert light to electricity.
They have many applications.
More recently, they are starting to be used in assemblies of solar modules connected to the electricity grid through an inverter, often in combination with net metering.
Three generations of development
The first generation photovoltaic consists of a large-area, single layer p-n junction diode, which is capable of generating usable electrical energy from light sources with the wavelengths of sunlight.
These cells are typically made using a silicon wafer.
First generation photovoltaic cells (also known as silicon wafer-based solar cells) are the dominant technology in the commercial production of solar cells, accounting for more than 86% of the solar cell market.
The second generation of photovoltaic materials is based on the use of thin-film deposits of semiconductors.
These devices were initially designed to be high-efficiency, multiple junction photovoltaic cells.
Later, the advantage of using a thin-film of material was noted, reducing the mass of material required for cell design.
This contributed to a prediction of greatly reduced costs for thin film solar cells.
Currently (2007) there are different technologies/semiconductor materials under investigation or in mass production, such as amorphous silicon, poly-crystalline silicon, micro-crystalline silicon, cadmium telluride, copper indium selenide/sulfide.
Typically, the efficiencies of thin-film solar cells are lower compared with silicon (wafer-based) solar cells, but manufacturing costs are also lower, so that a lower price in terms of $/watt of electrical output can be achieved.
Another advantage of the reduced mass is that less support is needed when placing panels on rooftops and it allows fitting panels on light materials or flexible materials, even textiles.
This allows for portable roll-up solar panels, which can fit in a backpack and be used to power cell phones or laptops in remote areas.
Third generation photovoltaics are very different from the other two, broadly defined as semiconductor devices which do not rely on a traditional p-n junction to separate photogenerated charge carriers.
These new devices include photoelectrochemical cells, Polymer solar cells, and nanocrystal solar cells.
Companies working on third generation photovoltaics include Xsunx, Konarka Technologies, Inc., Nanosolar and Nanosys.
Research is also being done in this area by the USA's National Renewable Energy Laboratory (http://www.nrel.gov/).
PVNET European Roadman for PV R&D  Ed Arnulf Jager-Waldan Office for Publications of the European Union 2004
Directory of Solar Cell Manufacturers
Directory of Solar Cell Manufacturing Equipment Suppliers
School of Photovoltaic and Renewable Energy Engineering (Research lab of Prof. Martin Green et al.)
Energex: Animation of how a solar cell works
Carbon Nanotube Solar Cells  (28 February 2005)
Flexible Silicon Solar Cells (15 February 2003)
Historical: Photovoltaic Solar Energy Conversion: An Update (M. Green, 1998)
Howstuffworks.com: How Solar Cells Work
Organic Photovoltaics and Materials — Overview
Organic Solar Cells for the Near-Infrared Spectrum
Photovoltaic Residential Benefits
Photovoltaic Solar Panel Overview
Photovoltaic Thin Films for the Full Solar Spectrum  (W. Walukiewicz 2002)
Pliable solar cells are on a roll
Điện mặt trời Địa Cầu Xanh
Superefficient, Cost-Effective Solar Cell Breaks Conversion Records - 40.7 percent efficiency achieved (Scientific American, December 2006)
Do-it-yourself
PEC (Photo Electro Chromic)
How to Build Your Own Solar Cell
DIY (Do It Yourself): Nanocrystalline Dye-Sensitized Solar Cell Kit Quote: "... sunlight-to-electrical energy conversion efficiency is between 1 and 0.5%..."
Cuprous oxide solar cells
Make a Solar Cell in Your Kitchen, A Flat Panel Solar Battery
Newsgroups
alt.solar.photovoltaic
An alternating current (AC) is an electric current of which magnitude and direction vary, unlike direct current, whose direction remains constant.
This means that the direction of current flowing in a circuit is constantly being reversed back and forth.
This is done with any type of AC voltage source.
The usual waveform of an AC power circuit is a sine wave, because this leads to the most efficient transmission of energy.
However, in certain applications different waveforms are used, such as triangular or square waves.
Inexpensive power inverters produce a square wave with a pause between the change in direction.
When one speaks of alternating current one mostly refers to the form in which electricity is delivered to businesses and residences.
The AC comes from a power plant.
The direction of the electricity switches back 60 times every second (or 50 times in some parts of the world).
This happens so fast that a light bulb does not stop glowing.
Both audio and radio signals carried on electrical wire are also examples of alternating current.
In these applications, an important goal is often the recovery of information encoded (or modulated) onto the AC signal.
Nikola Tesla experimented with electrical resonance and studied various lighting systems.
He invented an induction motor, new types of generators and transformers, and a system of alternating current power transmission.
William Stanley, Jr. designed one of the first practical devices to transfer AC power efficiently between isolated circuits.
Using pairs of coils wound on a common iron core, his design, called an induction coil, was an early precursor of the modern transformer.
The system used today was devised in the late nineteenth century, largely by Nikola Tesla.
Contributions were also made by George Westinghouse, Lucien Gaulard, John Dixon Gibbs,Wilhelm Siemens and Oliver Shallenger.
AC systems overcame the limitations of the direct current system used by Thomas Edison to distribute electricity efficiently over long distances.
The Mill Creek hydroelectric plant was built near Redlands, California in 1893.
Designed by Almirian Decker, it used 10,000 volt three-phase electric power which eventually became the standard method for power stations throughout the world.
AC power is cheaper and easier to make electronic devices.
The power switches for AC power are also less expensive to make.
It is less expensive than DC because you can increase and decrease the current very easily.
AC can use high voltages with smaller current to reduce losses when you send power.
AC reduces the heating in the wires.
DC power could be sent, but it would lose a lot of energy and you would have to put more work in it to send it great distances.
AC transformers are installed everywhere, including atop utility poles and underground.
Alternating current works by switching the current many times back and forth constantly while it goes back to the source it came from.
Willam A. Meyers, History and Reflections on the Way Things Were: Mill Creek Power Plant - Making History with AC, IEEE Power Engineering Review, February 1997, Pages 22–24
What is alternating current (AC)? -
on All About Circuits
"AC/DC: What's the Difference?".
Edison's Miracle of Light, American Experience. (
PBS)
"AC/DC: Inside the AC Generator ".
Kuphaldt, Tony R., "Lessons In Electric Circuits : Volume II - AC".
March 8, 2003. (
Design Science License)
Nave, C. R., "Alternating Current Circuits Concepts".
HyperPhysics.
"Alternating Current (AC)".
Magnetic Particle Inspection, Nondestructive Testing Encyclopedia.
"Alternating current ".
Analog Process Control Services.
Hiob, Eric, "An Application of Trigonometry and Vectors to Alternating Current".
British Columbia Institute of Technology, 2004.
"Introduction to alternating current and transformers".
Integrated Publishing.
"Wind Energy Reference Manual Part 4: Electricity ".
Danish Wind Industry Association, 2003.
Keelin, "Alternating current Tools ".
JC Physics, 2002.
"Measurement -> ac ".
Williams, Trip "Kingpin", "Understanding Alternating Current, Some more power concepts".
"Table of Voltage, Frequency, TV Broadcasting system, Radio Broadcasting, by Country".
Professor Mark Csele's tour of the 25 Hz Rankine generating station
50/60 hertz information
AC circuits Animations and explanations of vector (phasor) representation of RLC circuits
Blalock, Thomas J., "The Frequency Changer Era: Interconnecting Systems of Varying Cycles ".
The history of various frequencies and interconversion schemes in the US at the beginning of the 20th century
Direct current (DC or "continuous current") is the flow of electricity in a single direction, from the negative to the positive terminals (potential, poles).
The direct current always flow in the same direction, distinguishing it from the alternating current (AC).
Direct current used to be called "Galvanic current".
Typically, the current goes through a conductor and other things that can carry DC.
DC is also sent through a vacuum as in electron beams or ion beams.
The first commercial electric power transmission was developed by Thomas Edison in the late nineteenth century using direct current.
Today nearly all electric power distribution uses alternating current because of the advantages with transformers and transmission.
High-voltage direct current is often used for transporting electricity to places far away.
AC/DC: What's the Difference?.
A snowmobile is a motorized vehicle used for travelling over snow.
It is like a car, only instead of wheels, it has treads.
Some snowmobiles have skis in the front for steering.
Adding snowmobile studs to the tread decreases the time and distance it takes to stop a snowmobile.
Once you make a decision to stop a snowmobile, the distance it will take to stop will be a combination of the speed of the machine, weight of the machine and the available friction and or the mechanical damping (which will equal the effective drag factor) between the snowmobile and the surface on which it is trying to stop.
If the surface is icy or hard-packed, the mechanical damping portion of the effective drag factor is decreased, leaving you with only the friction provided by the tread to stop.
Snowmobile studs made from steel or stainless steel with carbide tips are installed in the tread.
The studs are designed for specific terrains in varying lengths, shapes and materials.
The studs control acceleration, deceleration and maneuverability.
The correct amount and type of stud installed in an effective pattern will produce the best traction results.
While the Beatles gained experience performing in Hamburg, Germany, the Remo Four played at American Air Force bases in France.
Members of the two bands were friends, and often played at the same places back in Liverpool, or would go to watch each other perform.
After the Beatles became famous under Brian Epstein's management, Epstein signed up the Remo Four also.
He worked hard to promote the band, but they never achieved massive success as the Beatles had.
Epstein paired the Remo Four with a singer he also managed, called Tommy Quickly.
They made a series of singles together, but none became hits.
Quickly retired from music, and the Remo Four went on to work with other singers, including Billy J. Kramer.
They also released an album, titled Smile, on a German record label.
George Harrison was invited to record a movie soundtrack in late 1967.
Instead of working with the Beatles, he invited the Remo Four to work with him.
The movie, Wonderwall, got little exposure, but the soundtrack album, Wonderwall Music, became a minor hit the next year.
(positive) fractions
line segments (ordered by length)
Plane figures (ordered by area)
Solids (ordered by volume)
Angles (ordered by angular magnitude)
They had proven that the first two could not be the same, or even isomorphic systems of magnitude.
They did not consider negative magnitudes to be meaningful, and magnitude is still primarily used in contexts in which zero is either the lowest size, or less than all possible sizes.
The magnitude of a real number  is usually called the absolute value or modulus.
It is written as , and is defined by:
| x | = x, if x ≥ 0
| x | = -x, if x < 0
This gives the number's distance from zero on the real number line.
For example, the modulus of -5 is 5.
The magnitude of a vector  is called its norm, and is usually written as .
It measures the length of the vector.
For a three-dimensional vector , the norm can be calculated using the formula .
Practical math
A magnitude is never negative.
When comparing magnitudes, it is often helpful to use a logarithmic scale.
Real-world examples include the loudness of a sound (decibel), the brightness of a star, or the Richter scale of earthquake intensity.
A fraction is a number that shows how many equal parts there are.
When we write fractions, we show one number with a line above (or a slash next to) another number.
For example, ,  and 1/4.are different ways of writing the same fraction (in this case a quarter).
The top number tells us how many parts there are, and the bottom number tells us the total number of parts.
The top part of the fraction is called a numerator.
The bottom part of the fraction is called a denominator.
For example, for the fraction , the 1 is the numerator, and the 4 is the denominator.
Examples of fraction
A room where  of the people are girls, has 1 girl for every 4 people.
A cake can be thought of as being made up of 4 equal parts, where each is 1 part of 4.
This can be written as , and is called a "quarter".
Similarly, 2 parts of the cake (2 quarters) can be written , which is also equal to 1/2 (one-half).
Mathematical fractions
A fraction is a mathematical expression relating two quantities or numbers, where one divides the other.
When the two quantities are whole numbers (or integers), this is called a rational number (such as the fraction ).
When the two quantities are polynomials, this is called a rational function.
Mathematically, a fraction is a quotient of numbers, representing the number's value when the numerator (upper number) is divided by the denominator (lower number).
Thus  means one divided by two, or, in decimals, 0.5.
To find  of , the denominators are multiplied, and because denominator 2 multiplied by 2 equals 4, we have that  x  = , or 0.5 x 0.5 = 0.25.
(In this case, “ of” means "multiplication".)
To find  divided by , multiply  by the reciprocal of , which is 2.
That answer is 1.
Multiplying
To multiply two fractions, the first numerator is multiplied by the other numerator, and the first denominator is multiplied by the other denominator.
x  = .
One can simplify this by dividing both numbers by a common factor.
This would be  after the simplication.
Mixed number
Curricula for Creating Fractions
Worksheets:Fractions
Interactive and dynamic worksheets to visualize fractions
Worksheets: Identifying Fractions
Worksheets: Improper Fractions to Mixed Numbers
Curricula for Teaching about Equivalent Fractions
Free online quizzes about Fractions
Printable fraction worksheets for elementary grades.
Brian Patrick Carroll, better known as Buckethead, is an American musician and songwriter.
As of 2016 he has released 255 solo albums.
He has performed on over 50 more albums by other music artists.
His music spans many different styles and genres.
Although he can play many different types of musical instruments, Buckethead is best known for his guitar playing.
He has been voted as a top guitarist in many magazines dedicated to the topic of guitar playing.
Buckethead records and performs onstage as a solo artist most of the time.
He has also worked with a wide variety musicians including: Bill Laswell, Bootsy Collins, Bernie Worrell, Iggy Pop, Les Claypool, Serj Tankian, Mike Patton and Viggo Mortensen.
Buckethead was a member of Guns N' Roses from 2000 to 2004.
Buckethead has created music for movies such as: Saw II, Ghosts of Mars, Beverly Hills Ninja and Last Action Hero.
In mathematics, the quotient is the result of a division.
For example, in the division of 6÷3, the quotient would be 2.
Here, 6 is also called the dividend, and 3 the divisor.
The quotient can thus be expressed as the number of times the divisor adds together into the dividend.
On the other hand, a quotient can also mean just the integral part of the result of dividing two integers.
For example, the quotient of 17 ÷ 5 would be 3 (since 5 goes into 17 at most 3 times), whilst the remainder, the leftover of the division, would be 2.
Quotients also come up in certain tests, like the IQ test, which evaluates one's intelligence quotient.
In this case, the quotient is the score of the test.
In recent decades, as people begin to emphasize multi-dimensional personal development, other similar quotients (such as emotional quotient) are being developed and considered as well.
Norman is a language spoken mainly in Normandy.
It is a Romance language (a language which comes from Latin).
It is closely related to French and is often called "Norman French".
After the Norman Conquest, Norman changed the English language considerably.
Jèrriais on Jersey
Guernésiais on Guernsey
Auregnais on the Guernsey dependency of Alderney
Sercquiais on the dependency of Sark
No one now uses Sercquiais or Auregnais as their first language, but Jèrriais and Guernésiais  are still used.
In mathematics, the word "division" means the operation which is the opposite of multiplication.
The symbols for division are the slash () and the fraction line, as in:
where each of the three expressions means "6 divided by 3", with 2 as the answer.
The first number is the dividend (6), and the second number is the divisor (3).
The result (or answer) of a division is the quotient, where any left-over amount as whole numbers is called the "remainder".
For example,  gives quotient 3 with remainder 2, all expressed as the mixed number  or 3.5).
The numbers involved in division can be very big, such as the case with two hundred: , or with 7 billion:  (where the quotient is equal to 7 million).
With multiplication
If  times  equals , written as:
where  is not zero, then  divided by  equals , written as:
In the above expression,  is called the dividend,  the divisor and  the quotient.
Division is most often shown by placing the dividend over the divisor with a horizontal line, also called a vinculum, between them.
For example,  divided by  is written as
This can be read as "a divided by b", or "a over b".
A way to express division all on one line is to write the dividend, then a slash, then the divisor, like this:
a⁄b
Any of these forms can be used to display a fraction.
A fraction is a division expression where both dividend and divisor are integers (in which case, the two numbers are typically referred to as numerator and denominator).
A fraction is an accepted way of writing numbers.
It is not always expected that the result of the division is written in decimals.
In some non-English-speaking cultures, "a divided by b" is written as .
However, in English-speaking countries the colon is restricted to expressing the related concept of ratios (where  reads "a is to b").
Divisor, another meaning as a number which evenly divides an amount
Division on a Japanese abacus selected from Abacus: Mystery of the Bead
Chinese Short Division Techniques on a Suan Pan
Rules of divisibility
Division (mathematics), a binary operation that serves as the inverse of multiplication
Division (electronics), digital implementation of mathematical division
Division (vote), a manner by which the votes of legislators are recorded
Division (horticulture), a method of vegetative plant propagation, or the plants created by using this method
Division (music) a specific type of ornamentation, most common in 17th century English music
Cell division, how biological cells multiply
Continental divide, the geographical term for separation between watersheds
North-South divide, the geopolitical term for the division between rich nations and poor nations
Division (organisation), a subsidiary of a larger organisation
Division (business), a separate named business operated as a part of an organization
Division (military), a unit typically consisting of from 10,000 to 20,000 troops
Police division, a large unit (often a Basic Command Unit) of the British police
Division (sport), a group of teams in sport
Division (botany), a classification of plants (the botanical counterpart to zoology's phylum)
Administrative division, part of a country
A county constituency or Parliamentary seat in the UK Parliament
A subpart of a hundred (division), former administrative unit in England and Wales
Census division
A grouping of pipe ranks in a pipe organ, often with its own case, windchest, and keyboard
Divisions, a type of variation form used in the baroque.
Division viol, an English Renaissance instrument
In nautical navigation the compass is called dividers
For the second operand of a division, see division (mathematics).
In mathematics, a divisor of an integer n, also called a factor of n, is an integer which divides n without leaving a remainder.
The statement "m is a divisor of n" can be written as .
Any number is always divisible by 1 and itself, which are two of the divisors.