Format of Video DVD

Although the capacity of storage in the DVD is great, the not compressed data of video of a film, never could fit in a DVD. In order to be able to insert a film in a DVD, a compressor makes lack of video. A called group MPEG (Moving Picture Experts Group), establishes the standards to compress the films in digital format. When the films are put in the DVDs, they are codified in stored format MPEG-2 and next in the disc. The compression format widely is accepted like an international standard. Your reproducer DVD contains a coder MPEG-2, who can decompress these data as fast as your you can see the film.
Reduction as large as the data
A film normally is filmed to an average of 24 plots per second. This means that every second, are 24 complete images in the screen. The Japanese American televisions use a called format NTSC, which unfolds a total of 30 plots per second, although it does in a sequence of 60 fields, containing each alternative lines of the image. Other countries, like Spain, use the format the PAL, that unfolds 50 fields per second, but with a greater resolution. When existing this difference between averages of plots and resolution, a film MPEG needs to be formatted for a system or another one, (NTSC or the PAL).
The coder MPEG who creates the compressed film, analyzes each plot and decides like codifying it. The compression uses a little the same technology that uses the compressors of digital photographies to eliminate duplicated or irrelevant data. Also it uses information of other plots to reduce the complete size of the file. Each plot can be codified in one of the three following ways:

• Like one intraframe, which contains a complete image of the data for that plot. This method to codify provides with the smaller compression.
• One “predicted frame”, which contains sufficient information to say to him to reproducer DVD as to show to the plot based on infraframe or predicted frames more recent.
• Bidirectional. In order to show this type of plot, the reproducer must have the information of infraframe or predicting adjacent. The USA the interpolation to calculate the position and color of each pixel.
  

Following the type of scene, the coder will decide that type of plots to use. For example, if there is a scene of very fast action that must be turned, where the things change from a plot to another one quickly, many infraframes will have more to be codified. All this can sound something complicated, but already you will have realized to amount of work that needs to make your reproducer DVD to decode a film MPEG-2. A great amount is needed processing and also codecs necessary to make work it.

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What are the electrons?

A s-electron a particle subatomics of negative load. It can free (not be connected to an atom, or be conexionado to the nucleus of an atom. The electrons in atoms exist in spherical armors of several radii, representing the energy levels. At the most great they are these spherical armors, greater will be the energy than it contains the electron.

In the electrical conductors, the current flows are resulting of the movements of atom electrons to atom individually, and of the negative poles to the positives generally. In the semiconducting materials, the current happens by the movement of electrons, but in some cases, he is more illustrative to see the current like a movement of deficiencies of the atom electron atom. An atom with deficiencies in a semiconductor is called hollow. These hollows move generally of positive the electrical poles to the negatives.

To put it another way, the s-electrons the particles smaller than they are within atoms. The atoms consist of protons (loaded positively), neutrons (without load) and electrons (loaded negative). You can imagine atoms as if they were a planet where it has some meteorites around orbiting to his. The planet represents the nucleus which consists of protons and neutrons, and the meteors orbiting are the electrons. These electrons move at a high speed around the nucleus.

Nevertheless, the electrons do not escape to the influence of the nucleus because they are tied by forces maintain that them in a continuous orbit.

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How work the microprocessors?

The computer that you are using right now to read this page Web uses a microprocessor to carry out its work. The microprocessor is the heart of any normal computer. Or a servant or a laptop, all needs one, and or a Pentium, Sparc or anyone of the many existing marks or types of microprocessors, will approximately do the same of a very similar form.
A microprocessor - also known as CPU or central unit process - is a complete element of computation, made in a single chip. The first microprocessor was the Intel 4004, which was introduced in 1971. He was not too powerful - everything what could make add and remain, and only could simultaneously do it with 4 bits. Even so, the incredible thing was that all these functions were in a single chip. Previously to this first model of microprocessor, the engineers constructed computers with long collections of Chips or more discreet components, like the transistors. Like anecdote, microprocessor 4004 was integrated in one of the first portable electronic calculators.
The logic behind a microprocessor
In order to understand as a microprocessor works, he is very useful to watch in his interior and to learn of the logic used when creating one. In order to know all the process it would be necessary to even learn assembly language - officially the language of the machines and the native language of the microprocessors, but we will try to simplify it a little for a greater understanding of its operation.
A microprocessor executes a series of instructions in the language previously mentioned to say to him to the processor that is what must do. Being based on these instructions, a microprocessor makes three things basic:

• Using its arithmetical logical drive (ALU), a microprocessor can conduct mathematical operations like adding, remaining to multiply and to divide. The modern microprocessors contain floating processors that can conduct operations very sophisticated.
• A microprocessor can move data of a location from memory to another one.
• A microprocessor can make decisions and to jump to a new group of instructions based on those decisions.

A microprocessor can make things very complex, but the previous described functions, are the basic ones to consider. Internamente in a microprocessor, we can find the following elements:

• A address bus, that can be of 8, 16 or 32 bits, and that east address takes to the memory.
• A bus of data, that can be of the same bits previously mentioned, that can send data to the memory and receive data of the memory.
• A line of reading (RD) and another one of writing (WR) to say to him to the memory if it wants to form or to locate the address.
• A line for the clock that sends pulses in sequence to the processor.
• A line to resetear the accountant of the program to zero and to reinitiate the execution.

Memory in the microprocessors
Until now it has been spoken on the address of the instructions and the buses of data, and the lines of writing and reading. These buses and lines must go connected to rom memory and ram, generally to both.
Rom memory - It is a memory of only reading (Read Only Memory). A chip ROM is formed by a series of predefined bytes. The bus says to the chip ROM to him that byte to take and to locate in the bus of data. When the line reading changes its state, this chip presents/displays the byte selected in the bus of data indicated above.
Ram memory - It is a ram (Random Memory Access). It contains bytes of information, and the microprocessor can read or write in those bytes following if the lines of reading and writing are signalized. This type of memory forgets all the information that contains once the energy goes out. By this the computer needs the rom memory.

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Operation of the plasma screens

In the past years, the great majority of the televisions has been constructed around the same technology: The cathode ray tube (CRT). In a television with this model of screen, which at the outset were televisions of black and white, they used a device which it generated a negative particle electron  ray, within a great glass tube. The electrons excite extended phosphorus atoms at the end of the tube by the screen, which causes that the phosphorus atoms are illuminated. The image of the television is produced when illuminating different areas from the phosphorus cover with different colors from different intensity.

The cathode ray tubes usually produce hummings, vibrant images and some other disadvantages, like their size for example. If you want to increase the width of the screen in a CRT, also it is necessary to increase the length of the tube, to give the device that generates the electron ray, more space to reach all the corners of the screen. By this same one, a monitor CRT of many inches will weigh one ton and will occupy much space in a room.

Nevertheless, a new alternative appeared not much ago, and are the plasma screens. These televisions have wide, comparable screens to great monitors CRT but with the difference that has a thickness of about fifteen centimeters. If you have read our article on as a CRT in the main section of television works, then you understand the basic idea of a television or standard monitor. Based on the information of a video signal, the television ignites thousand of small called points pixels, with electrons of high power and distributing them by the screen. Combining the colors in different proportions, the television can produce all the phantom that compose the colors.


The basic idea of a plasma screen, is to illuminate small and fluorescent lights to form an image. Each pixel is formed by 3 fluorescent lights - a red light, a green light and a blue light. Like a television CRT, the plasmas varies the intensity of the different lights to produce a complete rank of colors.

What is plasma?

The central element in a fluorescent light is the plasma, a gas made of ions (loaded atoms electrically) and electrons (charged particles negatively). Under normal conditions, a gas is compound mainly of particles without load. This means that the individual atoms of the gas include equal number of protons and electrons. The loaded electrons negatively are synchronized perfectly with loaded protons positively, reason why the atom has a zero load.

If you introduce many free electrons within the gas when establishing an electrical voltage by means, the situation changes quickly. The free electrons collide with the atoms, causing that lose other electrons. With a missing electron, an atom loses the balance. A positive charge would already exist causing that is an ion.

In the plasma screens with a conventional charge circulating around their interior, the particles of negative load run quickly towards the area of positive charge of the plasma and vice versa. In these wild movements, the particles are continuously striking themselves to each other. These collisions excite the atoms of the gas in the plasma causing that release energy photons. The used atoms of xeon and neon in the plasma screens release to lights photonics when they are excited.

The plasma screen is formed of cells vertical ordinates in horizontal lines and columns, forming a species of grid. Each particular cell has gas that must be ionized, and for it loads of electrodes are sent that are intersectioned with the cells. It is done thousand of times in a fraction of second, loading each one of the cells in turns.

When the loads have been realised, an electrical charge passes through the gas in the cell, creating a loaded particle flux that stimulates gas atoms to release photons with ultraviolet rays. The photons interact with the phosphorus material that covers the internal wall with the cell. Each pixel is compound of three separated cells, each with different phosphorus colors, calls subpixels. Each sub-cell has the colors red, green and blue. These three colors are based together to create the final color of the pixel.

Varying the pulses of the flows before mentioned by the different cells, the intensity of each subpixel can be controlled, to create hundreds of combinations different from the three colors and to include all the phantom.

The main advantage of the plasma screens is that screens can be produced very fine material very great and wide using. When illuminating itself each pixel separately, the resulting image is very shining and of very good quality from any angle. The greater disadvantage of this type of screens continues being its price, although the slope of these prices is progressive and good supplies can already be found.

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How works an electronic circuit?

Before explaining what is an electronic circuit, we will give to a review to which is an electrical circuit first. When you are using a battery, a generator set or a solar panel to produce electricity, are three things that always are equal:

• The origin of the electricity will have two terminals: a positive terminal and a negative terminal.
• The origin of the electric flux - or a generator, battery, etc. - will want to push electrons outside its negative terminal a certain voltage. For example, a battery AA normally wants to push those electrons 1.5 volts.
• The electrons will have to flow from the negative terminal to the positive terminal by means of a copper cable or another type of conductor. When there is a way that goes from the negative terminal to the positive, you have a circuit, and the electrons can flow by the cable.
• You can include a load of any type (a light bulb, a motor, a television, etc.), in center of the circuit. The electricity source will feed the load, and the load will make its function (to create light, to generate images, to take a motor, etc.).

The electronic circuits can be returned very complex, but at a very basic level, always you have the source of the electricity (battery), the load and two cables to lead the electricity between the battery and the load. The electrons move from the origin, by the load and of return to the origin.
The electrons that move have energy. According to electrons they move from a point to another one, can carry out a work. For example, in an incandescent filament light bulb, the energy of electrons is used to create heat, and the heat to create light as well. In an electrical motor, the energy in electrons creates a magnetic field, and this field can interact with others (by attraction and magnetic repulsion) to create movement.
The electronic circuit
Basing us on the explained thing until the moment, an electronic circuit is an electrical circuit that also contains devices such as electronic transistors, valves and other elements. The electronic circuits can do functions complex using the electrical charges, although they are governed with the same laws that the electrical circuits. The electronic circuits can be classified in three groups, which are:

• Analogical circuits - They are those in which the electrical signals vary continuously to correspond with the represented information. The electronic equipment like the power or voltage amplifiers, radios, televisions, usually are analogical excluding many modern devices that usually use digital circuits. The basic units of the analogical circuits are liabilities - resistance, counsellors, inducers - and independent assets, power plants and dependent power plants.
  
• Digital circuits - In these circuits, the electrical signals obtain discreet values to show numerical and logical values that they represent the information to process. The transistors are used mainly like commutators to create footbridges logics. Some examples of electronic equipment that use digital circuits are the calculators, PDAs and the microprocessors.
  

Mixed circuits - These circuits are hybrid and contain analogical elements as much as digital. Some examples of these circuits are the converters of analogical to digitalis and vice versa

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What is Clock Rate?

The clock rate is the rate in cycles per second (measured in hertz) or the frequency of the clock in any synchronous circuit, such as a central processing unit (CPU). For example, a crystal oscillator frequency reference typically is synonymous with a fixed sinusoidal waveform, a clock rate is that frequency reference translated by electronic circuitry (AD Converter) into a corresponding square wave pulse [typically] pr sampling rate for digital electronics applications. In this context the use of the word, speed (physical movement), should not be confused with frequency or its corresponding clock rate. Thus, the term "clock speed" is a misnomer.
A single clock cycle (typically shorter than a nanosecond in modern non-embedded microprocessors) toggles between a logical zero and a logical one state.
CPU manufacturers typically charge premium prices for CPUs that operate at higher clock rates, a practice called binning. For a given CPU, the clock rates are determined at the end of the manufacturing process through actual testing of each CPU. CPUs that are tested as complying with a given set of standards may be labeled with a higher clock rate, e.g., 1.50 GHz, while those that fail the standards of the higher clock rate yet pass the standards of a lesser clock rate may be labeled with the lesser clock rate, e.g., 1.33 GHz, and sold at a lower price.
The clock of a CPU is normally determined by the frequency of an oscillator crystal. The first commercial PC, the Altair 8800 (by MITS), used an Intel 8080 CPU with a clock rate of 2 MHz (2 million cycles/second). The original IBM PC (c. 1981) had a clock rate of 4.77 MHz (4,772,727 cycles/second). In 1995, Intel's P5 Pentium chip ran at 100 MHz (100 million cycles/second), and in 2002, an Intel Pentium 4 model was introduced as the first CPU with a clock rate of 3 GHz (three billion cycles/second corresponding to ~0.3 10⁻⁹seconds per cycle).
With any particular CPU, replacing the crystal with another crystal that oscillates half the frequency ("underclocking") will generally make the CPU run at half the performance. It will also make the CPU produce roughly half as much waste heat. Conversely, some people try to increase performance of a CPU by replacing the oscillator crystal with a higher frequency crystal ("overclocking").^[1] However, the amount of overclocking is limited by the time for the CPU to settle after each pulse, and by the extra heat created.
After each clock pulse, the signal lines inside the CPU need time to settle to their new state. That is, every signal line must finish transitioning from 0 to 1, or from 1 to 0. If the next clock pulse comes before that, the results will be incorrect. Chip manufacturers publish a "maximum clock rate" specification, and they test chips before selling them to make sure they meet that specification, even when executing the most complicated instructions with the data patterns that take the longest to settle (testing at the temperature and voltage that runs the lowest performance).
Also, some energy is wasted as heat (mostly inside the driving transistors) whenever a signal line makes a transition from the 0 to the 1 state or vice versa. When executing complicated instructions that cause many transitions, higher clock rates produce more heat. If electricity is converted to heat faster than a particular computer cooling system can cool it, then the transistors may get hot enough to be destroyed.
Engineers continue to find new ways to design CPUs that settle a little more quickly or use slightly less energy per transition, pushing back those limits, producing new CPUs that can run at slightly higher clock rates. The ultimate limits to energy per transition are explored in reversible computing, although no reversible computers have yet been implemented. Engineers have struggled to design CPUs that run much faster than about 3.5 GHz due to thermodynamic limits in current semiconductor process technologies and other limitations. The highest clock speed microprocessor ever sold commercially to date is found inside IBM's zEnterprise 196 mainframe, introduced in July, 2010. The z196's cores run continuously at 5.2 GHz.
Engineers also continue to find new ways to design CPUs so that, although they may run at the same or a lower clock rate as older CPUs, they get more instructions completed per clock cycle.

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How work the infrared?

In order to understand as the infrared work, it is important to understand something on the light. The amount of energy in a light wave, is related to the wavelength: The shorter wavelengths have a greater energy. Of the visible light, the violet is the one that has more energy, and the red the one that less. Exactly next to the phantom of visible light, it is the infrared phantom.
The infrared light can be separated in three categories:

• Infrared near - more near the visible light, and it has a 1,3 wavelength that varies from the 0,7 to microns.
• Infrared near - With wavelengths that go from 1,3 to 3 microns. The previous category and this, are used in a variety of electronicses, as control of remote control is the case of them.
• Thermal infrared - the phantom of the infrared Occupies most of, and has the 30 rank from the 3 to microns.

The difference between this last and two first, are that the thermal infrared are emitted by an object instead of to be reflected by. The infrared light is emitted by an object reason why it is happening to an atomic level. The atoms are in continuous movement, and we excited if them with an external agent, they produce energy and light. In our tutorial on the technology laser we give a good explanation of how this works.Any thing that is alive, produces energy, and thus they also make some things inanimate as they can be the motors or the rockets. The power consumption produces heat. In return, the heat cause that the objects in an object ignite photons in the infrared phantom. The more it warms up it is the object, the more it cuts will be the wavelength of the infrared photon that has been released. An object that is very hot will even begin to emit photons in the visible phantom, shining in a red tone, and moving through orange, yellow, blue and finally the target.
The applications of the infrared vary in an ample rank of possibilities, that they can go from night vision, to the use in meteorology or astronomy. The military use that has occurred to the infrared mainly has been previously mentioned night vision, monitoring, location of objectives and tracking. Many devices to investigate the space, use this technology in their telescopes to penetrate in regions with cosmic dust and to detect new objects in the universe.
The border between the visible light and the infrared light is not defined of a precise form. The human eye is not too sensible to the light from 700 nm of wavelength, reason why the short frequencies do not contribute too much to common zones with common power plants. Nevertheless, particularly intense lights, like the laser, can be detected until the 780 nm, and will be perceived like red light. The line of the infrared is defined - in agreement with the standards - between 700 and 800 nm.

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