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Shade

A place is called in the shade when the sun is shining, and some object, a tree for example, blocks the direct sunlight. So the sunlight can not reach the spot. The dark image, which the object casts on the ground is called shadow, not shade. Sha ...

                                               

Snells law

Snells Law of Refraction is the scientific law of the refraction of light or other waves. In optics, Snells law is about the speed of light in different media. The law states that when light passes through different materials the ratio of sines o ...

                                               

Stroboscopic disc

The stroboscopic disc was the first tool that showed a moving picture. It is also known as phenakisticope or phenakistoscope. Simon von Stampfer, and Joseph Antoine Ferdinand Plateau each invented it separately at the start of the 1830s. In 1833, ...

                                               

Transparency

In optics, transparency is the property of allowing light to pass through something. An object that is transparent can be seen through. That is, what is on the other side of the object can be seen through it. The image you can see through a trans ...

                                               

Visible spectrum

The visible spectrum is the part of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will react to wavelengths in ai ...

                                               

Automatic train operation

                                               

Billups Neon Crossing Signal

The Billups Neon Crossing Signal was a special signal to warn car and truck drivers that a train was coming. It was placed at a dangerous Illinois Central railroad crossing on Mississippi State Route 7 in Grenada, Mississippi. It was put up in th ...

                                               

Bogie

A bogie is a chassis, with wheels, attached to a rail vehicle, such as a boxcar. A bogie usually has four or six wheels. Each rail vehicle has a pair of bogies. The bogies can turn slightly to allow the rail vehicle to pass easily around curves i ...

                                               

Bow collector

A bow collector is one of the three main devices used on tramcars to transfer electric current from the overhead lines above to the tram below. While once very common in continental Europe, it has now been largely replaced by the pantograph.

                                               

Communications-based train control

Communications-based train control is a railway signaling system that makes use of telecommunications between the train and track equipment. By means of a CBTC system, the exact position of a train is known more accurately than with the tradition ...

                                               

Head-end power

Head-end power or Electric train supply is the electric power distribution system on a passenger train. The power source, usually a locomotive at the front or head of a train, provides the electricity used for heating, lighting, air conditioning, ...

                                               

Overhead lines

Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point. This may be abbreviated to OHL or OHLE for OverHead Line Equipment.

                                               

Pantograph (rail)

A pantograph is a device that collects electric current from overhead lines for electric trains or trams. The term stems from the resemblance to pantograph devices for copying writing and drawings.

                                               

Railway electrification system

A railway electrification system supplies electrical energy to railway locomotives and multiple units so that they can operate without having an on-board prime mover. Their main advantages are high energy efficiency and low operating cost. Buildi ...

                                               

Railway semaphore signal

One of the earliest forms of fixed railway signal is the semaphore. These signals display their different indications to train drivers by changing the angle of inclination of a pivoted arm.

                                               

Railway signal

A railway signal or just signal is a mechanical or electrical machine that gives train drivers or engineers information about the line ahead. These traffic signals say whether the train must stop or may continue and what speed the train may go. I ...

                                               

Third rail

A third rail is a metal railway track that is placed on either side of a train track to provide electrical power to trains traveling along the tracks. They are often used on subways and local train services. Before third rails, electricity was ca ...

                                               

TOPS

Total Operations Processing System, or TOPS, is a computer system for managing the locomotives and rolling stock owned by a rail system. It was originally developed by the Southern Pacific Railroad and was widely sold; it is best known in the Uni ...

                                               

Trolley pole

A trolley pole is a tapered cylindrical pole of wood or metal, used to transfer electricity from a "live" overhead wire to the control and propulsion equipment of a tram or trolley bus. The use of overhead wire in a railway electrification system ...

                                               

BFG 9000

The BFG 9000 is a fictional futuristic weapon. It is found in the Doom video game series. The BFG 9000 is a very large, solid metal gun. It shoot balls of green plasma. It is the most powerful weapon in the games. The BFG 9000 can destroy almost ...

                                               

Death Star

The Death Star is a fictional moon-sized space station and superweapon. It was invented for the Star Wars movies. It was a huge spherical space station which fired a ray of energy which could destroy a planet.

                                               

Force field

A force field is a field of energy that usually blocks something. The force field is common in science fiction and fantasy stories. The ideal of a force field may be from the vector field, thought it resembled the warding spells, the protective m ...

                                               

Ice-nine

Ice-nine is a fictional material. It was invented by author Kurt Vonnegut in his novel, Cats Cradle. Ice-nine was a special type of ice that would freeze at higher temperatures than normal ice. When dropped into other bodies of water, it froze th ...

                                               

Ion cannon

In science fiction, an ion cannon is a beam weapon. It shoots beams of ions. Because of its power, it is usually said to be a superweapon. An ion cannon is a type of particle cannon. The particles it shoots are ionized. Because of their electrica ...

                                               

Mecha

Mecha are walking vehicles run by a pilot, often shown in science fiction or fantasy with a futuristic element. Some stories, such as the Manga Patlabor and American miniatures game Battletech, also show mecha doing civilian purposes such as heav ...

                                               

Physical system

In physics, a physical system is any object or part of an object that can be analysed with the laws of physics. An atom or the water in a lake can both be considered as physical systems. Everything outside the system is called the environment, wh ...

                                               

System

A system is a group of related things that work together as a whole. These things can be real or imaginary. Systems can be man-made things like a car engine or natural things like a star system. Systems can also be concepts made by people to orga ...

                                               

Black box

A black box, in science and engineering, is a box whose inside working is not known. It is a device, system or object with input and output. There is no knowledge of its internal workings. The way it works is "opaque" black. Almost anything might ...

                                               

Centimetre-gram-second system of units

The centimetre-gram-second system is a variant of the metric system. The derived units are on the centimeter as the unit of length, the gram as a unit of mass and the second as a unit of time. The system evolved in the nineteenth century when it ...

                                               

Complex system

A complex system is one where smaller elements make complex things happen. These smaller elements can be simple elements or they can be complex systems within themselves. Any such complex elements can be interrelated in simple or complex ways and ...

                                               

Complexity

Complexity is a property of something with many parts and a complicated arrangement. It is also the state of being complex. Its opposite is simplicity. In science, complexity is also the name for systems science.

                                               

Control theory

Control theory is an interdisciplinary branch of engineering and mathematics. It deals with the behavior of systems. The desired output of a system is called the reference. In that context, a system can be influenced by certain input values. Depe ...

                                               

Cybernetics

Cybernetics is the study of control and communication in the animal and the machine. Norbert Wiener added: "Information is information, not matter or energy". 155 Ross Ashby defined it as: "the art of steermanship. co-ordination, regulation and c ...

                                               

Deterministic system

In mathematics, and natural science, a deterministic system is a system where the current state the system does not depend on random factors. It only depends on previous states, and time. A deterministic model will always produce the same state a ...

                                               

Disk partition

A disk partition is a section of a data storage device. A disk partition can have one of several formats, such as NTFS to ext4. Disk partitions start at one number and end at another. These numbers are addresses in the hard drive. The address poi ...

                                               

Duodecimal

The duodecimal system is the number system with a base of twelve. In the duodecimal system, large numbers are expressed by groups of 12. For example, the number fifty would be written as 42 in the dozenal system, since it is equal to 4×12+2. The ...

                                               

Electronic system

A electronic system that is powered by electricity, and it processes informations, datas, or any raw material from input into a desired output for further usage in life. Inputs - Electrical or mechanical sensors, which take signals from the physi ...

                                               

Expert system

An expert system is a program running on a computer. Like a human expert, it knows a lot about a subject. People can ask the expert system a question. The expert system will then use a set of rules and give answers to the question. This method of ...

                                               

File system

A File system is a way of storing all data on a data storage device. The data is usually organized in computer files in directories. Below the file system there is usually a physical device where the files are stored. This might be a hard disk, U ...

                                               

International System of Units

The International System of Units is the standard modern form of the metric system. The name of this system can be shortened or abbreviated to SI, from the French name S ysteme I nternational dunites. The International System of Units is a system ...

                                               

Metre Convention

The Metre Convention is the treaty that set up the International Bureau of Weights and Measures. The BIPM is an inter-governmental organization that is responsible for harmonizing systems of measurement across the world. The treaty was first made ...

                                               

Metric system

The metric system is a number of different systems of measurement with length based on the metre, mass on the gram, and volume on the litre. This system is used around the world. It was developed in France and first introduced there in 1795, 2 ye ...

                                               

Numeral system

A numeral system is a way to write numbers. Roman numerals and tally marks are examples. "11" usually means eleven, but if the numeral system is binary, then "11" means three. A numeral is a symbol or group of symbols, or a word in a natural lang ...

                                               

Parliamentary procedure

Parliamentary procedure is a commonly accepted way in which a group of people work together to discuss and make decisions. It is a set of rules for meetings.

                                               

Parliamentary republic

In a parliamentary system, the legislature is the part of government that makes laws. The legislature also gives power to the executive the part of government that enforces laws. This is the basic form of a parliamentary republic. The difference ...

                                               

Parliamentary system

A parliamentary system of government means that the executive branch of government has the direct or indirect support of the parliament. This support is usually shown by a vote of confidence. A balanced relationship between the executive and the ...

                                               

Partition table

A partition table maps out partitions onto a storage device. The two biggest examples are MBR and GPT. Others include Apple Partition Map, which is used in Apple computers, and BSD disklabel. MBR, or Master Boot Record, is a section at the very b ...

                                               

Structure

In science, structure is a fundamental concept. It means the arrangement of parts. Examples are the organs in a body, or crystals in a substance like granite. A structure may refer to buildings, machines and similar things made by people as well ...

                                               

System of units

A system of units is a collection of units of measurement. The quantities described by the units are related to each other by specific rules. These rules may not contradict each other. An example of a system like this is one needed for the proble ...

                                               

Systems engineering

Systems engineering is a field of engineering that deals with complex engineering projects which should be designed and managed over the life cycle of the project. Therefore, issues such as logistics, the coordination of different teams, and auto ...

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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!

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