microprocessor based auto synchronization

The manual method of synchronization demands a skilled operator and the method is suitable for no load operation or normal frequency condition. under emergency condition such as lowering of frequency or synchronizing of large machines a very fast action is needed, which may not be possible for a human operator. Thus there is a need of autosynchroniser in a power station or in an industrial establishment where generator are employed. This paper describes a microprocessor based set up for synchronizing a three phase alternator to a busbar. Also existing methods of synchronization are mentioned.

Molecular Electronics:A new technology competitive to semiconductor technology

Semiconductor integration beyond Ultra Large Scale Integration (ULSI), through conventional electronic technology facing some problems with fundamental physical limitations. Beyond ULSI, a new technology may become competitive to semiconductor technology. This new technology is known is as Molecular Electronics.

Molecular based electronics can overcome the fundamental physical and economic issues limiting Si technology. Here, molecules will be used in place of semiconductor, creating electronic circuit small that their size will be measured in atoms. By using molecular scale technology, we can realize molecular AND gates, OR gates, XOR gates etc.

The dramatic reduction in size, and the sheer enormity of numbers in manufacture, are the principle benefits promised by the field of molecular electronics

MANUFACTURING THROUGH ELECTRO CHEMICAL MACHINING

ABSTRACT:
The machining of complex shaped designs was difficult earlier, but with the advent of the new machining processes incorporating in it chemical, electrical & mechanical processes manufacturing has redefined itself. This paper intends to deal with one of the revolutionary process called Electro Chemical Machining (ECM).

INTRODUCTION:
Electro chemical machining (ECM) is the controlled removal of metal by anodic dissolution in an electrolytic medium in which the work piece is the anode & the tool is the cathode.
Working: Two electrodes are placed at a distance of about 0.5mm & immersed in an electrolyte, which is a solution of sodium chloride. When an electrical potential of about 20V is applied between the electrodes, the ions existing in the electrodes migrate toward the electrodes.
Positively charged ions are attracted towards the cathode & negatively charged towards the anode. This initiates the flow of current in the electrolyte. The electrolysis process that takes place at the cathode liberates hydroxyl ions & free hydrogen. The hydroxyl ion combines with the metal ions of anode to form insoluble metal hydroxides &the material is thus removed from the anode. This process continues and the tool reproduces its shape in the work piece (anode). The high current densities promote rapid generation of metal hydroxides and gas bubble in the small spacing between the electrodes. These become a barrier to the electrolyzing current after a few seconds. To maintain a continuous high density current, these products have to be removed continuously. This is achieved by circulating the electrolyte at high velocity through the gap between the electrodes. It is also to be noted that the machining gap size increases. Therefore to maintain a constant gap the cathode should be advanced towards the anode at the same rate at which the material is removed.

Magnetic resonance imaging (MRI):most modern scanning techniques

Magnetic resonance imaging (MRI) is one of the most modern techniques which uses the principle of magnetic resonance to create the images of body parts for diagnostic purposes. When the resonating magnetic object is a an automatic nucleus, it is called nuclear magnetic resonance (NMR) the use of NMR to produce images of the body is called magnetic resonance imaging (MRI) Magnetic nuclei in the human body act like tiny bar magnets with north and south poles. When the body is placed in a large magnetic field, these bar magnet 1ine with the external magnetic field. Then by passing a radio frequency pulse through the body some of these little magnets absorb energy and change direction. When the radio waves are turned of, the body’s nuclei return to the original orientation releasing the absorbed energy and this is processed by a computer in to image.

Maglev: A combination of super conducting magnets and linear motor technology

Ever since the discovery of the wheel, man has been in constant pursuit to achieve better and faster means of transportation. Maglev means magnetic levitation. It is the system which magnetically levitates the vehicle. These ultra high speed trains are acting as an indispossible resource to make the world smaller.

Maglev is a generic term for a family of technologies in which a vehicle is suspended, Guided and propelled by magnetic forces. the basic idea of a maglev is to levitate it with magnetic fields. So there is no physical contacts between the train and rails. Recent developments in cryogenics, superconductivity, power electronics, aerodynamics and vehicle dynamics has led to a renewed. Maglev can move people and goods with much mobility and speed, using much less energy at lower cost and with greatly reduced pollution compared to the existing modes of transport.

2010 seminar topic Multi-wavelength and Broadband Optical Sources for Fiber-Optic Communication

Tunable lasers in the C and L bands of fiber-optic communication have been designed with erbium-doped fiber. Tunability has been achieved without using an intra-cavity filter, merely by changing the intro-cavity parameters in an appropriate manner. Also, mode-locking at GHz frequencies with a very simple economical design is a highlight of this work. The large tuning range possible in this design is further utilized in demonstrating a broadband source by introducing a dispersion shifted fiber as an intra cavity element. The multiple four-wave mixing processes occurring between the longitudinal modes in this fiber result in a spectral broadening throughout the gain spectrum of the EDF. This is a simple and elegant design to realize a tunable broadband source at pump powers less than 200 mW. The mechanism of broadband generation and the utility of the source for applications will be discussed.

MIDI

MIDI is an acronym that stands for musical instrument digital interface. It is means for instruments to communicate to each other and or computers. MIDI can do many things one of the most popular things is sequencing. A sequencer is any hardware or software that allows recording music into memory. We can do things with good sequences that we can’t do even with the most expensive multi-track tape recorders, such as transposing without changing tempo and sound quality. Likewise we can large the tempo without affecting these patch or sound quality. MIDI can allow creating ensembles using two or more instruments and/or computers with many of today’s computers, wee can download songs and play them in our computer internally using a “MIDI Player” if we don’t like the downloaded MIDI song completely we can edit to our liking with a sequencer. MIDI will allow playing an instrument that normally would not know how to play. For example, a MIDI guitar will allow a guitar player to enjoy the sound of other instruments, such as a piano it can be as blessing for people who either have only one band or can only process one hand at a time.

MAGNATORESISTIVE RAM (MRAM)

MRAM that uses magnetic properties to store data. This new type of chip will compete with other forms established forms of semiconductor memory, such as Flash and RAM.Most engineers believe that the technology, called MRAM could reduce the cost and power consumption of electronics for cell phones, music players, laptops, and servers. The feature that makes MRAM an alluring alternative to other forms of semiconductor memory is the way it stores data. Flash memory and RAM, for example,Hold information as electric charge. In contrast, MRAM uses the magnetic orientation Of electrons to represent bits. Hold data with out a power supply and can be written to and read from an unlimited number of times. Reading and writing data from MRAM is also fast, taking a matter of nanoseconds. MRAM is able to hold data without power.

Mathematical markup languages

A mathematical markup language is a computer notation for representing mathematical formulae, based on mathematical notation. Specialized markup languages are necessary because computers normally deal with linear text and more limited character sets (although increasing support for Unicode is obsoleting very simple uses). A formally standardized syntax also allows a computer to interpret otherwise ambiguous content, for rendering or even evaluating. For computer-interpretable syntaxes, the most popular are TeX/LaTeX and MathML.



More details :

MPEG-7

MPEG-7 is a multimedia content description standard. This description will be associated with the content itself, to allow fast and efficient searching for material that is of interest to the user. MPEG-7 is formally called Multimedia Content Description Interface. Thus, it is not a standard which deals with the actual encoding of moving pictures and audio, like MPEG-1, MPEG-2 and MPEG-4. It uses XML to store metadata, and can be attached to timecode in order to tag particular events, or synchronise lyrics to a song, for example.

It was designed to standardize:
a set of Description Schemes (short DS in the standard) and Descriptors (short D in the standard)
a language to specify these schemes, called the Description Definition Language (short DDL in the standard)
a scheme for coding the description

The combination of MPEG-4 and MPEG-7 has been referred to as MPEG-47.

MPEG-7 objectives
Provide a fast and efficient searching, filtering and content identification method.
Describe main issues about the content (low-level characteristics, structure, models, collections, etc.).
Index a big range of applications.
Audiovisual information that MPEG-7 deals is : Audio, voice, video, images, graphs and 3D models
Inform about how objects are combined in a scene.
Independence between description and the information itself.


MPEG-7 applications

There are many applications and application domains which will benefit from the MPEG-7 standard. A few application examples are:
Digital library: Image/video catalogue, musical dictionary.
Multimedia directory services: e.g. yellow pages.
Broadcast media selection: Radio channel, TV channel.
Multimedia editing: Personalized electronic news service, media authoring.
Security services: Traffic control, production chains...
E-business: Searching process of products.
Cultural services: Art-galleries, museums...
Educational applications.
Biomedical applications.

MAGNETOHYDRODYNAMIC POWER GENERATION TECHNOLOGY (MHD)

The Magnetohydrodynamic power generation technology (MHD ) is the production of electrical power utilising a high temperature conducting plasma moving through an intense magnetic field. The conversion process in MHD was initially described by Michael Faraday in 1893. However the actual utilisation of this concept remained unthinkable. The first known attempt to develop an MHD generator was made at Westing house research laboratory (USA) around 1936. The efficiencies of all modern thermal power generating system lies between 35-40% as they have to reject large quantities of heat to the environment. In all other conventional power plant, first the thermal energy of the gas is directly converted in to electrical energy. Hence it is known as direct energy conversion system. The MHD power plants are classified in to Open and Closed cycle based on the nature of processing of the working fluid. With the present research and development programmes, the MHD power generation may play an important role in the power industry in future to help the present crisis of power. The MHD process can be used not only for commercial power generation but also for so may other applications. The economic attractiveness of MHD for bulk generation of power from fossil fuel has been indicated in many design studies and cost estimates of conceptual plants. MHD promises a dramatic improvement in the cost of generating electricity from coal, beneficial to the growth of the national economy. The extensive use of MHD can help in saving billions of dollars towards fuel prospects of much better fuel utilization are most important, but the potential of lower capital costs with increased utilization of invested capital provides also a very important economic incentive. The beneficial environmental aspects of MHD are probably of equal or even greater significance. The MHD energy conversion process cab contribute greatly to the solution of the serious air and thermal pollution problems faced by all steam - electric power plants while it simultaneously assures better utilization for our natural resources. It can therefore be claimed that the development of MHD for electric utility power generation is an objective of national significance. The high temperature MHD process makes it possible to take advantage of the highest flame temperatures which can be produced by combustion from fossil fuel. While commercial nuclear reactors able to provide heat for MHD have yet to be developed, the combined use to MHD with nuclear heat source holds great promise for the future. In India, coal is by far the most abundant fossil fuel and thus the major energy source for fossil fueled MHD power generation. Before large central station power plants with coal as the energy source can be become commercially viable, further development is necessary.

Microvia Technology

Microvias are small holes in the range of 50 -100 µm. In most cases they are blind vias from the outer layers to the first innerlayer.
The development of very complex Integrated Circuits (ICs) with extremely high input/output counts coupled with the steadily increasing clock rates has forced the electronic manufacturer to develop new packaging and assembly techniques. Components with pitches less then 0.30 mm, chip scale packages, and flip chip technology are underlining this trend and highlight the importance of new printed wiring board technologies able to cope with the requirement of modern electronics.
In addition, more and more electronic devices have to be portable and consequently systems integration, volume and weight considerations are gaining importance.
These portables are usually battery powered resulting in a trend towards lower voltage power supplies, with their implication in PCB (Printed Circuit Board) complexity.
As a result of the above considerations, the future PCB will be characterized by very high interconnection density with finer lines and spaces, smaller holes and decreasing thickness. To gain more landing pads for small footprint components the use of microvias becomes a must.

Microbe-Powered 'Fart' Machine Stores Energy

It sounds like a gag gift instead of serious science, but a new electrical farting machine could improve fuel cell technology by turning C02 in the atmosphere into methane.

The technique won't combat global warming directly, since both CO2 and methane are potent greenhouse gases, but it could help store alternative energies such as wind and solar more efficiently.

It works like this: giving small jolts of electricity to single-celled microorganisms known as archea prompts them to remove C02 from the air and turn it into methane, released as tiny "farts." The methane, in turn, can be used to power fuel cells or to store the electrical energy chemically until its needed.

"We found that we can directly convert electrical current into methane using a very specific microorganism," said Bruce Logan, a professor at Pennsylvania State University, who details his discovery in the journal Environmental Science and Technology.

Multimedia messaging Service

A picture says more than a thousand words and is more fun to look at!!! . Everyone in this world believes in this quote. And this is also one of the main quotes that inspired mobile developers who gave this hot technology -MMS.




MMS, Multimedia Messaging Service, is a standardized messaging service. It traced its roots from SMS (Short Messaging Services) and EMS (Enhanced Messaging Services) .MMS will allow users to send and receive messages exploiting the whole array of media types available today, e.g. text, images, audio, and video, text.

Graphics, data, animations, while also making it possible to support new content types as they become popular. With MMS, for example, users could send each other personal pictures together with a voice message, such as a greeting card with a picture, handwritten message, and a personal song or sound clip that has been recorded by the user itself. Video conferencing, which is expected to make a great impact in the future, is also possible with this technology. Using the Wireless Application Protocol (WAP) as bearer technology and powered by the high-speed transmission technologies EDGE, GPRS and UMTS (WCDMA), Multimedia Messaging allows users to send and receive messages that look like PowerPoint-style Presentations.

MMS supports standard image formats such as GIF and JPEG, video formats such as MPEG 4, and audio formats such as MP3, MIDI and WAV, also the new AMR.

The greatest advantage of MMS is its ability to interact with mobile to mobile terminals as well as with mobile to PDA Laptop Internet and other data devices.

MMS can also act as a virtual email client. Greatly anticipated by young users in particular, MMS is projected to fuel the growth of related market segments by as much as forty percent.

A picture says more than a thousand words and is more fun to look at!!! . Everyone in this world believes in this quote. And this is also one of the main quotes that inspired mobile developers who gave this hot technology -MMS.

MMS, Multimedia Messaging Service, is a standardized messaging service. It traced its roots from SMS (Short Messaging Services) and EMS (Enhanced Messaging Services) .MMS will allow users to send and receive messages exploiting the whole array of media types available today, e.g. text, images, audio, and video, text.

Graphics, data, animations, while also making it possible to support new content types as they become popular. With MMS, for example, users could send each other personal pictures together with a voice message, such as a greeting card with a picture, handwritten message, and a personal song or sound clip that has been recorded by the user itself. Video conferencing, which is expected to make a great impact in the future, is also possible with this technology. Using the Wireless Application Protocol (WAP) as bearer technology and powered by the high-speed transmission technologies EDGE, GPRS and UMTS (WCDMA), Multimedia Messaging allows users to send and receive messages that look like PowerPoint-style Presentations.