Integrated Gate Commutated Thyristor (IGCT)

The Integrated Gate Commutated Thyristor (IGCT) combines the advantages of the hard driven GTO thyristor, including its dramatically improved turn- off performance, with technological breakthroughs at the device, gate-drive and application levels. Homogenous switching area of the IGCT up to the dynamic avalanche limits. Snubber circuits are no longer needed. Improved loss characteristics allow high frequency applications extending into the kHz range. A new IGCT device family with integrated high- power diodes has been developed for applications in the 0.5-6 MVA range, extending to several 100 MVA with series and parallel connections. A first 100 MVA inverter based on the IGCT has been in commercial operation and confirms the very high level of reliability of this new technology. Other new application using the IGCT platform includes ABB’s new ACS1000 drive for medium voltage applications.

BiCMOS silicon technology:Electronics Seminar

The need for high-performance, low-power, and low-cost systems for network transport and wireless communications is driving silicon technology toward higher speed, higher integration, and more functionality. Further more, this integration of RF and analog mixed-signal circuits into high-performance digital signal-processing (DSP) systems must be done with minimum cost overhead to be commercially viable. While some analog and RF designs have been attempted in mainstream digital-only complimentary metal-oxide semiconductor (CMOS) technologies, almost all designs that require stringent RF performance use bipolar or semiconductor technology. Silicon integrated circuit (IC) products that, at present, require modern bipolar or BiCMOS silicon technology in wired application space include the essential optical network (SONET) and synchronous digital hierarchy (SDH) operating at 10 Gb/s and higher.

The viability of a mixed digital/analog. RF chip depends on the cost of making the silicon with the required elements; in practice, it must approximate the cost of the CMOS wafer, Cycle times for processing the wafer should not significantly exceed cycle times for a digital CMOS wafer. Yields of the SOC chip must be similar to those of a multi-chip implementation. Much of this article will examine process techniques that achieve the objectives of low cost, rapid cycle time, and solid yield.

Adaptive Piezoelectric energy harvesting circuit

This paper describes an approach to harvesting electrical energy from a mechanically excited piezoelectric element. A vibrating piezoelectric device differs from a typical electrical power source in that it has a capacitive rather than inductive source impedance, and may be driven by mechanical vibrations of varying amplitude. An analytical expression for the optimal power flow from a rectified piezoelectric device is derived, and an “energy harvesting “ circuit is proposed which can achieve this optimal power flow. The harvesting circuit consists of an ac-dc rectifier with an output capacitor, an electrochemical battery, and a switch-mode dc-dc converter that controls the energy flow into the battery. An adaptive control technique for the dc-dc converter is used to continuously implement the optimal power transfer theory and maximize the power stored by the battery. Experimental result reveal that the use of the adaptive dc-dc converter increases power transfer by over 400% as compared to when the dc-dc converter is not used.

Coordinated secondary voltage control to eliminate voltage violation in power system contingencies

In order to achieve more efficient voltage regulation in a power system, coordinated secondary voltage control has been proposed, bringing in the extra benefit of enhancement of power system voltage stability margin. The study is presented by the e.g. with two SVCs and two STATCOMs in order to eliminate voltage violation in systems contingencies. In the paper, it is proposed that the secondary voltage control is implemented by a learning fuzzy logic controller. A key parameter of the controller is trained by P-type learning algorithm via offline simulation with the assistance of injection of artificial loads in controller’s adjacent locations. A multiagent collaboration protocol, which is graphically represented as a finite state machine, is proposed in the paper for the coordination among multiple SVCs and STATCOMs. As an agent, each SVC or STATCOM can provide multilocation coverage to eliminate voltage violation at its adjacent nodes in the power system. Agents can provide collaborative support to each other which is coordinated according to the proposed collaboration protocol.

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

Tele-Immersion (TI) :Free full Engineering seminar reort

It is 2010 and you have a very important meeting with your business associates in Chennai. However you have visitors from Japan coming for a mega business deal the same day. Is there any technology by which you can deal with both of them? The answer is yes and the name of that technology is Tele-Immersion. Tele-Immersion is a technology by which you’ll interact instantly with your friend on the other side of the globe through a simulated holographic environment. This technology, which will come along with Internet2, will change the way we work, study and get medical help. It will change the way we live. Tele-Immersion (TI) is defined as the integration of audio and video conferencing, via image-based modeling, with collaborative virtual reality (CVR) in the context of data-mining & significant computation. The 3D effect behind the tele-immersion makes it feel like the real thing. The ultimate goal of TI is not merely to reproduce a real face-to-face meeting in every detail, but to provide the “next generation” interface for collaborators, world-wide, to work together in a virtual environment that is seamlessly enhanced by computation and large databases. When participants are tele-immersed, they are able to see and interact with each other and objects in a shared virtual environment.

Tele-immersion can be of immense use in medical industry and it also finds its application in the field of education

Cylinder Deactivation: A fast emerging technology to save fuel

With alternatives to the petrol engine being announced ever so often you could be forgiven for thinking that the old favorite the petrol engine is on its last legs but nothing could be further from the truth and possibilities for developing the petrol engines are endless. One of the most crucial jobs on the agenda is to find ways of reducing fuel consumption, cutting emissions of the green house gas CO2 and also the toxic emissions which threaten air quality. One such fast emerging technology is cylinder deactivation where a number of cylinders are shut down when less is needed to save fuel.
The simple fact is that when you only need small amounts of power such as crawling around town what you really need is a smaller engine. To put it another way an engine performs most efficiently when its working harder so ask it to do the work of an engine half its size and efficiency suffers. Pumping or throttling losses are mostly to blame. Cylinder deactivation is one of the technologies that improve fuel economy, the objective of which is to reduce engine pumping losses under certain vehicle operating conditions.

When a petrol engine is working with the throttle wide open pumping losses are minimal. But at part throttle the engine wastes energy trying to breathe through a restricted airway and the bigger engine, the bigger the problem. Deactivating half the cylinders at part load is much like temporarily fitting a smaller engine.
During World War II, enterprising car owners disconnected a spark plug wire or two in hopes of stretching their precious gasoline ration. Unfortunately, it didn’t improve gas mileage. Nevertheless, Cadillac resurrected the concept out of desperation during the second energy crisis. The “modulated displacement 6.0L V-8- 6-4” introduced in 1981 disabled two, then four cylinders during part-throttle operation to improve the gas mileage of every model in Cadillac’s lineup. A digital dash display reported not only range, average mpg, and instantaneous mpg, but also how many cylinders were operating. Customers enjoyed the mileage boost but not the
side effects. Many of them ordered dealers to cure their Cadillacs of the shakes and stumbles even if that meant disconnecting the modulated-displacement system


Like wide ties, short skirts and $2-per-gallon gas, snoozing cylinders are back. General Motors, the first to show renewed interest in the idea, calls it Displacement on Demand (DoD). DaimlerChrysler, the first manufacturer to hit the U.S. market with a modern cylinder shut-down system calls its approach Multi- Displacement System (MDS). And Honda, who beat everyone to the punch by equipping Japanese-market Inspire models with cylinder deactivation last year, calls the approach Variable Cylinder Management (VCM)
The motivation is the same as before — improved gas mileage. Disabling cylinders finally makes sense because of the strides achieved in electronic power train controls. According to GM, computing power has been increased 50-fold in the past two decades and the memory available for control algorithms is 100 times greater. This time around, manufacturers expect to disable unnecessary cylinders so seamlessly that the driver never knows what’s happening under the hood.

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.

CHEMICAL ROCKET ENGINES

Chemical rocket engines, like those on the space shuttle, work by burning two gases to create heat, which causes the gases to expand and exit the engine through a nozzle. In so doing they create the thrust that lifts the shuttle into orbit. Smaller chemical engines are used to change orbits or to keep satellites in a particular orbit. For getting to very distant parts of the solar system chemical engines have the drawback in that it takes an enormous amount of fuel to deliver the payload. Consider the Saturn V rocket that put men on the moon: 5,000,000 pounds of its total take off weight of 6,000,000 pounds was fuel. The problem is that all the energy for chemical engines comes from the energy stored in the propellants.
Electric rocket engines use batteries, solar power, or some other energy source to accelerate and expel charged particles. These rocket engines have extremely high specific impulses, so they are very efficient, but they produce low thrusts. The thrusts that they produce are sufficient only to accelerate small objects, changing the object’s speed by a small amount in the vacuum of space. However, given enough time, these low thrusts can gradually accelerate objects to high speeds. This makes electric propulsion suitable only for travel in space. Because electric rockets are so efficient and produce small thrusts, however, they use very little fuel. Some electric rockets can provide thrust for years, making them ideal for deep-space missions. Satellites or other spacecraft that use electric rockets for propulsion must be first boosted into space by more powerful chemical rockets or launched from a spacecraft.

CARBON NANOTUBES

Carbon Nanotubes -- tiny tubes about 10,000 times thinner than a human hair -- consist of rolled up sheets of carbon hexagons.
HISTORY
Discovered in 1991 by researchers at NEC, they have the potential for use as minuscule wires or in ultrasmall electronic devices.
To build those devices, scientists must be able to manipulate the Nanotubes in a controlled way.
DEVELOPMENT

IBM researchers using an atomic force microscope (AFM), an instrument whose tip can apply accurately measured forces to atoms and molecules, have recently devised a means of changing a nanotube's position, shape and orientation, as well as cutting it.

Continuously variable transmission (CVT):A potential solution to this fuel economy dilemma

After more than a century of research and development, the internal combustion (IC) engine is nearing both perfection and obsolescence: engineers continue to explore the outer limits of IC efficiency and performance, but advancements in fuel economy and emissions have effectively stalled. While many IC vehicles meet Low Emissions Vehicle standards, these will give way to new, stricter government regulations in the very near future. With limited room for improvement, automobile manufacturers have begun full-scale development of alternative power vehicles. Still, manufacturers are loath to scrap a century of development and billions or possibly even trillions of dollars in IC infrastructure, especially for technologies with no history of commercial success. Thus, the ideal interim solution is to further optimize the overall efficiency of IC vehicles.
One potential solution to this fuel economy dilemma is the continuously variable transmission (CVT), an old idea that has only recently become a bastion of hope to automakers. CVTs could potentially allow IC vehicles to meet the first wave of new fuel regulations while development of hybrid electric and fuel cell vehicles continues. Rather than selecting one of four or five gears, a CVT constantly changes its gear ratio to optimize engine efficiency with a perfectly smooth torque-speed curve. This improves both gas mileage and acceleration compared to traditional transmissions.
The fundamental theory behind CVTs has undeniable potential, but lax fuel regulations and booming sales in recent years have given manufacturers a sense of complacency: if consumers are buying millions of cars with conventional transmissions, why spend billions to develop and manufacture CVTs?
Although CVTs have been used in automobiles for decades, limited torque capabilities and questionable reliability have inhibited their growth. Today, however, ongoing CVT research has led to ever-more robust transmissions, and thus ever-more-diverse automotive applications. As CVT development continues, manufacturing costs will be further reduced and performance will continue to increase, which will in turn increase the demand for further development. This cycle of improvement will ultimately give CVTs a solid foundation in the world’s automotive infrastructure.

CRYOGENIC ENGINES :CRYOGENICS- BIRTH OF AN ERA

Cryogenics originated from two Greek words “kyros” which means cold or freezing and “genes” which means born or produced. Cryogenics is the study of very low temperatures or the production of the same. Liquefied gases like liquid nitrogen and liquid oxygen are used in many cryogenic applications. Liquid nitrogen is the most commonly used element in cryogenics and is legally purchasable around the world. Liquid helium is also commonly used and allows for the lowest temperatures to be reached. These gases can be stored on large tanks called Dewar tanks, named after James Dewar, who first liquefied hydrogen, or in giant tanks used for commercial applications.

The field of cryogenics advanced when during world war two, when metals were frozen to low temperatures showed more wear resistance. In 1966, a company was formed, called CyroTech, which experimented with the possibility of using cryogenic tempering instead of Heat Treating, for increasing the life of metal tools. The theory was based on the existing theory of heat treating, which was lowering the temperatures to room temperatures from high temperatures and supposing that further descent would allow more strength for further strength increase. Unfortunately for the newly-born industry the results were unstable as the components sometimes experienced thermal shock when cooled too fast. Luckily with the use of applied research and the with the arrival of the modern computer this field has improved significantly, creating more stable results.
Another use of cryogenics is cryogenic fuels. Cryogenic fuels, mainly oxygen and nitrogen have been used as rocket fuels. The Indian Space Research Organisation (ISRO) is set to flight-test the indigenously developed cryogenic engine by early 2006, after the engine passed a 1000 second endurance test in 2003. It will form the final stage of the GSLV for putting it into orbit 36,000 km from earth.
It is also used for making highly sensitive sensors for detecting even the weakest signals reaching us from the stars. Most of these sensors must be cooled well below the room temperature to have the necessary sensitivity, for example, infrared sensors, x-ray spectrometers etc. The High resolution Airborne Widebandwidth Camera, for SOFIA (Stratospheric Observatory For Field Astronomy) which is a Boeing 747 flying observatory, a project of the University Of Chicago, Goddard Space Flight Center and the Rochester Institute Of Technology, which when enters into operation will be the largest infra-red telescope available, is cooled by an adiabatic demagnetization refrigerator operating at a temperature of 0.2K.
Another branch of cryogenics is cryonics, a field devoted to freeze people, which is used to freeze those who die of diseases, that they hope will be curable by the time scientists know how to revive people.

COMMON SYNTHETIC PLASTICS

INRODUCTION
Plastic molecules are made of long chains of repeating units called monomers. The atoms that make up a plastic’s monomers and the arrangement of the monomers within the molecule both determine many of the plastic’s properties. Plastics are one of the classification of polymers .If a polymer is shaped into hard and tough utility articles by the application of heat and pressure ,it is used as “plastic”.

Synthetic polymers are often referred to as "plastics", such as the well-known polyethylene and nylon. However, most of them can be classified in at least three main categories: thermoplastics, thermosets and elastomers.

Man-made polymers are used in a bewildering array of applications: food packaging, films, fibers, tubing, pipes, etc. The personal care industry also uses polymers to aid in texture of products, binding etc.

Examples
A non-exhaustive list of these ubiquitous materials includes:
acrylonitrile butadiene styrene (ABS)
polyamide (PA)
polybutadiene
poly(butylene terephthalate) (PBT)
polycarbonate
poly(ether sulphone) (PES, PES/PEES)
polyethylene (PE)
poly(ethylene glycol) (PEG)
poly(ethylene terephthalate) (PET)
polyimide
polypropylene (PP )
polystyrene (PS)
styrene acrylonitrile (SAN)
polyurethane (PU)
polyvinylchloride (PVC)

CAMLESS ENGINE

The cam has been an integral part of the IC engine from its invention. The cam controls the “breathing channels” of the IC engines, that is, the valves through which the fuel air mixture (in SI engines) or air (in CI engines) is supplied and exhaust driven out. Besieged by demands for better fuel economy, more power, and less pollution, motor engineers around the world are pursuing a radical “camless” design that promises to deliver the internal – combustion engine’s biggest efficiency improvement in years. The aim of all this effort is liberation from a constraint that has handcuffed performance since the birth of the internal-combustion engine more than a century ago. Camless engine technology is soon to be a reality for commercial vehicles. In the camless valve train, the valve motion is controlled directly by a valve actuator – there’s no camshaft or connecting mechanisms .Precise electro hydraulic camless valve train controls the valve operations, opening, closing etc. The seminar looks at the working of the electro hydraulic camless engine, its general features and benefits over conventional engines. The engines powering today’s vehicles, whether they burn gasoline or diesel fuel, rely on a system of valves to admit fuel and air to the cylinders and let exhaust gases escape after combustion. Rotating steel camshafts with precision-machined egg-shaped lobes, or cams, are the hard-tooled “brains” of the system. They push open the valves at the proper time and guide their closure, typically through an arrangement of pushrods, rocker arms, and other hardware. Stiff springs return the valves to their closed position. In an overhead-camshaft engine, a chain or belt driven by the crankshaft turns one or two camshafts located atop the cylinder head.
A single overhead camshaft (SOHC) design uses one camshaft to move rockers that open both inlet and exhaust valves. The double overhead camshaft (DOHC), or twin-cam, setup does away with the rockers and devotes one camshaft to the inlet valves and the other to the exhaust valves

ADAPTIVE CRUISE CONTROL

Mentally, driving is a highly demanding activity - a driver must maintain a high level of concentration for long periods and be ready to react within a split second to changing situations. In particular, drivers must constantly assess the distance and relative speed of vehicles in front and adjust their own speed accordingly.
Those tasks can now be performed by Adaptive Cruise Control (ACC) system, which is an extension of the conventional cruise control system.
Like a conventional cruise control system, ACC keeps the vehicle at a set constant speed. The significant difference, however, is that if a car with ACC is confronted with a slower moving vehicle ahead, it is automatically slowed down and then follows the slower vehicle at a set distance. Once the road ahead is clear again, the ACC accelerates the car back to the previous set cruising speed. In that way, ACC integrates a vehicle harmoniously into the traffic flow.

Abrasive water jet machine tools

Abrasive water jet machine tools are suddenly being a hit in the market since they are quick to program and could make money on short runs. They are quick to set up, and offer quick turn-around on the machine. They complement existing tools used for either primary or secondary operations and could make parts quickly out of virtually out of any material. One of the major advantage is that they do not heat the material. All sorts of intricate shapes are easy to make. They turns to be a money making machine.
So ultimately a machine shop without a water jet , is like a carpenter with out a hammer. Sure the carpenter can use the back of his crow bar to hammer in nails, but there is a better way. It is important to understand that abrasive jets are not the same thing as the water jet although they are nearly the same. Water Jet technology has been around since the early 1970s or so, and abrasive jets extended the concept about ten years later. Both technologies use the principle of pressuring water to extremely high pressure, and allowing the water to escape through opening typically called the orifice or jewel. Water jets use the beam of water exiting the orifice to cut soft stuffs like candy bars, but are not effective for cutting harder materials. The inlet water is typically pressurized between 20000 and 60000 Pounds Per Square Inch (PSI). This is forced through a tiny wall in the jewel which is typically .007” to .015” diameter (0.18 to0.4 mm) . This creates a vary high velocity beam of water. Abrasive jets use the same beam of water to accelerate abrasive particles to speeds fast enough to cut through much faster material

Aerospace Flywheel Development

Presently, energy storage on the Space Station and satellites is accomplished using chemical batteries; most commonly nickel hydrogen or nickel cadmium. A flywheel energy storage system is an alternative technology that is being considered for future space missions. Flywheels offer the advantage of a longer lifetime, higher efficiency and a greater depth of discharge than batteries. A flywheel energy storage system is being considered as a replacement for the traditional electrochemical battery system in spacecraft electrical power systems. The flywheel system is expected to improve both the depth of discharge and working life by a factor of 3 compared with its battery counterpart. Although flywheels have always been used in spacecraft navigation and guidance systems, their use for energy storage is new. However, the two functions can easily be combined into a single system. Several advanced technologies must be demonstrated for the flywheel energy storage system to be a viable option for future space missions. These include high strength composite materials, highly efficient high speed motor operation and control, and magnetic bearing levitation.

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.

Fault localization on ungrounded and high resistance grounded low voltage systems

One of the most common and difficult problems to solve in industrial power systems is the location and elimination of ground fault. Ground faults that occur in ungrounded and high resistance grounded systems do not draw enough current to trigger circuit breaker or fuse operation, making them difficult to localize. Techniques currently used to track down faults are time consuming and cumbersome. A new approach developed for ground fault localization on ungrounded and high resistance grounded low voltage systems is described. The system consists of a novel ground fault relay that operates in conjunction with low cost indicators permanently mounted in the circuit. The remote fault relay employs digital signal processing to detect the fault, identify the faulted phase and measure the electrical distance of the fault from the substation. The remote fault indicators are used to visually indicate where the fault is located. The resulting system provides a fast, easy, economical and safe detection system for ground fault localization.

FACTS :A concept introduced by Electric Power Research Institute (EPRI)

FACTS is a concept introduced by Electric Power Research Institute (EPRI), USA.It is actually a group of advanced transmission technologies that rely on high speed, solid-state electronics, rather than electromechanical devices. By this concept, the apparent impedance of a transmission line is controlled according to certain algorithm. Thus the power system operation is made more reliable, controllable and efficient.

FACT system is a promising method, which can be implemented into the system for enhancing system stability by damping out system oscillations. At the heart of FACT are thyristors, which permit control and switching of megawatt levels of power within milliseconds.

Electronic fuel injection system

In the electronic fuel injection system we use different sensor unit to assess accurate data from various engine parts and which is applied to Engine Control Unit (ECU), such as air manifold pressure, engine speed, crank shaft angle. ECU uses the data to calculate the required amount of fuel in the particular engine condition. This seminar deals with the basic principle of Electronic Fuel Injection (EFI).

Electric tractions:A pollutions free and energy efficient mode of transportations

Continuous development in semiconductor technology for the last three decades or more have led to the availability of a host of high power semiconductor devices and fast versatile VLSI (very large scale integration ) chips enabling proper control of such power devices. These developments have enabled a phenomenal growth of power electronics which basically deals with processing of electric power to make it suitably for various applications. A major application of power electronics in this period has been in the field of railways tractions all over the world. This had led to benefits like smoother drives for passenger comfort, energy conservation, higher operational speeds, cost effective maintenance besides helping the growth of electronics industry in general. Indian railways are helping the growth of electronics industry in general. Indian railways are one of the largest railways systems in the world and offer a big scope for applications of power electronics. From the late 60s few efforts have been made to introduce such systems with mixed results. Greater challenge lies before the Indian industry to make use of this particular application area for its growth.
Electric tractions is a pollutions free and energy efficient mode of transportations, it offers excellent alternative source of energy other than fossil fuels. Indian railways decided to go in for 25kv ac systems and selected main line heavy density routes.

Electronic nose(E-noses) A System that detect and identify odours and vapours

The harnessing of electronics to measure odour is greatly to be desired. Human panels backed up by gas chromatography and mass spectrometry are helpful in quantifying smells, but they time are consuming, expensive and seldom performed in real time in the field. So it is important that these traditional methods give way to a speedier procedure using and electronic nose composed of gas sensors. Electronic nose are E-noses are the systems that detect and identify odours and vapours, typically linking chemical sensing devices with signal processing, pattern recognition and artificial intelligence techniques which enable uses to readily extract relevant and reliable information.

CTs and PTs

With the increasing demand for electric power, the economics of power transmission requires the use of high transmission line voltages. This leads to escalation of cost for conventional CTs and PTs.

This paper provides an economical alternative, for the use of CTs and PTs for the measurement of current and voltage. The method is an optical method using lasers. The method employs two types of devices; free path and enclosed path devices. The basic principle of the optical method is based upon magneto-optic effect, electro optic effect and the electro gyration effect.

This paper concludes with the suggestion for future development. Instead of using free path, the enclosed path method is suggested.d88eafd484ee4ecf974e07836d1f6d30

Cryptography is the art of devising codes and ciphers

Cryptography is the art of devising codes and ciphers, and cryptoanalysis is the art of breaking them. Cryptology is the combination of the two. In the literature of cryptology, information to be encrypted is known as plaintext, and the parameters of the encryption function that transforms are collectively called a key.
Cryptology took on many forms in the centuries between the fall of Rome and the dawn of the Industrial Age. By the late 19th century, with the advent of the telegraph and wireless radio, cryptology took its permanent place as an important component of commercial, military and diplomatic communications. Rudimentary mechanical and electromechanical encoding inventions developed at the turn of the 20th century and through World War I laid the foundation for stronger and more efficient cipher devices.
With the dawn of the computer age, the possibilities for encryption methods and devices expanded exponentially. Machines with blazing fast computing power gave cryptographers the ability for the first time to design complicated encryption techniques.
The next great evolution in cryptology came with the introduction of microprocessor-powered computers. The rapid deployment of increasingly powerful desktops quickened the pace of cryptographic development, since even a moderately skilled computer user could break many of the algorithms in use.
Cryptology is more deeply rooted in every part of our communication and computing world than when it was first employed by ancient peoples. We use it to protect everything from e-mail to e-commerce transactions to personal diaries. As our dependency upon technology increases, so too will our dependency upon cryptography. After all, we all have things we want to keep secret.

Contactless Energy Transfer System (CETS)

Most mains operated equipment in use today is connected to the supply via plugs and sockets. These are generally acceptable in benign environments but can be unsafe or have limited life in the presence of moisture. In explosive atmospheres and in undersea applications special connectors must be used. This paper describes a technique, the Contactless Energy Transfer System (CETS), by which electrical energy maybe transmitted, without electrical connections or physical contact, through non-magnetic media of low conductivity. CETS, which has been used to transfer upto 5KWs across a 10mm gap, employs high frequency magnetic coupling and enables plug in power connections to be made in wet or hazardous environmental conditions without the risk of electric shock, short-circuiting or sparking. Energy may be transmitted without the necessity for accurately manufactured “plug and socket” mechanisms and may be transmitted from source to load even when there is a relative motion. Load source voltage matching may be made inherent to the system.

Condition monitoring of transformer: Electrical Seminar Topic

Transformers are a large part of the component structure of the electricity system. Knowing the condition is essential to meeting the goals of maximizing return on investment and lowering total cost associated with transformer operation.

In order to reconcile both decreasing maintenance spending and reliable service, condition based maintenance (CBM) is often proposed. The successful application of CBM lies in obtaining information transformers, so that, on the one hand, a critical condition will be noted early enough to take measures and on the other hand, so that only minimal maintenance is being applied to transformers still in good condition.

The paper covers the following areas.
• General aspects of aging in transformers.
• An overview of condition monitoring methodology with partial discharge patterns in focus.
• Partial discharge measurement and diagnostics on power transformer using a multi channel digital PD detector.

Brush-less servomotor

A brush-less servomotor has been developed by using interdisciplinary mechatronics engineering. A mechanical switching device (commutator) is replaced by electronic circuits and controllers resulting in maintenance free and high performance servo drive.
The brush-less servomotor is an ac motor, in all respects and is in fact called the ac servomotor. Combined with a dedicated control device, the performance of the brush-less servomotor is found to be equal to the performance of the high performance dc servo motor.
The rotational speed of dc servomotor is generally varied by changing the voltage applied to the armature. As the armature voltage is nearly proportional to the rotational speed, the speed can be slowed down as much as is required by lowering the applied voltage. On the other hand the rotational speed of the ac motor is generally varied by changing the frequency. However the frequency has its limits of variation. A wide range of speed variation, which is a feature of servomotors, cannot be obtained by using only a simple inverter.
In dc motor when the current flows in the electrical conductor, after passing through the brushes and the commutator in the magnetic field generated by permanent magnets N and S, torque is generated. For getting a stable torque proportional to current, the line of magnetic force should intersect the c of current at right angles in a dc motor. This is enabled by the use of rectifiers (a commutator and brushes).
In ac motors slip ring is used instead of a commutator and a power source of alternating current makes the rotor rotate continuously at the rotational speed corresponding to the applied frequency. But the brushes of the ac motors can be eliminated by changing the revolving armature structure in to revolving field type.

Axial-field electrical machines abstract

Axial-field electrical machines offer an alternative to the conventional machines. In the axial-field machine, the air gap flux is axial in direction and the active current carrying conductors are radially positioned. This paper presents the design characteristics, special features, manufacturing aspects and potential applications for axial-field electrical machines. The experimental from several prototypes, including d.c. machines, synchronous machines and single-phase machines are given. The special features of the axial-field machine, such as its planar and adjustable air gap, flat shape, ease of diversification, etc., enable axial-fled machines to have distinct advantages over conventional machines in certain applications, especially in special purpose applications.

Full report is available  :report4all@gmail.com

AUTOMATIC SOLAR TRACKER .Electrical seminar topics

A new control scheme for a single – phase diode clamped rectifier is proposed to achieve a unity power factor, balanced neutral point voltage and constant DC-bus voltage. Four power switches are used in the rectifier to generate a three-level PWM wave form on the rectifier terminal voltage.The line current command is derived from a DC-link voltage regulator and an output power estimator. The hysteresis current Controller is used to track the line current command. To balance the neutral-point voltage, a capacitor voltage compensator is employed. The main advantages of using a three-level instead of a two-level PWM scheme are that the blocking voltage of each power switch is clamped to half the DC-bus voltage (if the off –state resistance of  power switches is equal),and the voltage  harmonic on the AC  side of rectifier is reduced.

AUTOMATED DISTRIBUTION SYSTEM With Full seminar Report

Distribution systems are usually composed of radial feeders. Each feeder is divided into load sections with sectionalizing switches and is usually connected to other feeders via normally open tie switches.

 When a fault occurs in the distribution system, it is firstly detected by protection relays, then a circuit breaker is opened and de-energizes the feeder where the fault exists. By operating sectionalizing switches, the faulted section is isolated and the un-faulted sections disconnected are re-energized after reclosing the circuit breaker.

As automation is introduced into the distribution systems, the above switching operations can become automated. Recent advances in digital technology have made possible the development of Distribution Automation System (DAS). The DAS offers many new opportunities for improved system operation. It provides an integrated system approach to monitoring, protection, and control.

 Distribution automation includes wide spread functions, among which feeder automation is an important aspect. By controlling line switches installed on the feeder, feeder automation functions can be accomplished by identifying and isolating permanent feeder faults and restoring service to the un-faulted feeder sections sequentially and automatically, and thus reduce significantly customer outage time. The distribution automation discussed in this paper is restricted to fault isolation, reconfiguration, and service restoration switching operations.
For Full Report :report4all@gmail.com

Numerical modeling of active plasmonic nanoparticles

Enhanced scattering and light localization beyond the diffraction limit due to plasmon resonance in metallic nanoparticles is a well known phenomena and has been applied for a wide range of useful applications including nanoparticle waveguides, bio-sensors and several others. Based on the classical Mie theory it can be shown that by enclosing an active media in a nanoparticle, metallic losses can be overcome and a nanoparticle can be made to radiate by itself. This result can extend the use of plasmonic nanoparticles far beyond the current limitations and pave the way for lossless plasmonic waveguides, energy storage devices and nanolasers. This research aims to investigate, in theory and using numerical techniques, how these applications can be realized.

Ph.D. Seminar topic Analytical and Numerical Modeling of Subwavelength Plasmonic-waveguide Components for Nanophotonic Applications

Recently, in optics there has been a surge of interest in miniaturized metallic structures
that allow sub-wavelength control of electromagnetic energy in the infrared and visible
bands of the spectrum. This results an emerging field of science known as plasmonics,
which has plethora of applications such as nanoscale optical interconnects,
chemical/bio-sensors, high-resolution microscopy, etc.
This research aims to investigate various plasmonic waveguide-based optical
components in terms of equivalent transmission-line networks. This representation
allows one to use classical network analysis tools in microwave engineering to obtain
analytical expressions that describe the transmission response of useful devices in
nanophotonics. The derived formulae provide rapid design optimization paths unlike the
computationally expensive and time consuming numerical simulations.

Seminar on Photonic Band Gap Materials: Light Trapping Crystals

Photonic Band Gap (PBG) materials are artificial, periodic, dielectrics that enable engineering of the most fundamental properties of electromagnetic waves. These include the laws of refraction, diffraction, and spontaneous emission of light. Unlike traditional semiconductors that rely on the propagation of electrons through an atomic lattice, PBG materials execute their novel functions through selective trapping or localization of light. This is a fundamentally new and largely unexplored property of Maxwell's equations. This is also of practical importance for alloptical communications, information processing, efficient lighting, and solar energy trapping. Three dimensional (3D) PBG materials offer a unique opportunity to simultaneously (i) synthesize micron-scale 3D circuits of light that do not suffer from diffractive losses and (ii) engineer the electromagnetic vacuum density of states in this 3D optical micro-chip. This combined capability opens a new frontier in integrated optics as well as the basic science of radiation-matter interactions. I review recent approaches to micro-fabrication of photonic crystals with a large 3D PBG centered near 1.5 microns. These include direct laser-writing techniques, holographic lithography, and a newly invented optical phase mask lithography technique. I discuss consequences of PBG materials in classical and quantum electrodynamics.

Power transformers

Power transformers are the most significant pieces of equipment for electrical power delivery systems. One of the key parameters to be monitored in a power transformer is the internal temperature. High temperature accelerates the aging of winding paper insulation and increases the risk of bubbling under severe load conditions. Temperature is also an important parameter for transformer cooling system. The transformer winding hottest-spot temperature is one of a number of limiting factors for the loading capability of transformers. One way to increase the loading capability is to increase the efficiency of the cooling system by using fans and pumps. This research focuses on the investigation of the effect of the cooling system parameters, in particular the oil flow rate, on the thermal performance of power transformers.

Seminar on Optical Isolator: Application to Photonic Integrated Circuits

Optical active devices fail to operate in a desired manner, when unwanted reflections are launched into them. An optical isolator plays an essential role in protecting optical devices from unwanted reflections. Commercially available optical isolators based on a magneto-optic Faraday effect, which are provided with optical fiber and optical beam interfaces, are hard to be integrated with other optical devices. In case of waveguide isolators, it is quite unrealizable to use a rotation of polarization, because the precise control of waveguide birefringence is needed. Several approaches have been developed to avoid the precise control of waveguide geometry, like a nonreciprocal radiation and a nonreciprocal loss isolator. An interferometric waveguide isolator, which uses a nonreciprocal phase shift provided by the first-order magneto-optic effect, has the advantages of a single polarization operation and a wide operational wavelength range. Also, the interferometric isolator is realizable in several waveguide platforms by using a magneto-optic material in a cladding layer. To achieve this, we developed a direct bonding technique of magneto-optic garnet on III-V compound semiconductors and silicon waveguides. In this talk, the integration of optical isolators will be addressed, which includes a non-magneto-optic approach. 

reference :http://www.eng.monash.edu.au

Advanced Optical Functionalities in Photonic Crystals

High-quality self-assembled three-dimensionally-ordered photonic crystals have been synthesized with inorganic and polymeric colloids. These crystals display a pseudo bandgap in the UV / visible / near-IR regions with high values of reflectance combined with low transmission. The stop band characteristics have been modified after infiltrating these passive photonic crystals with materials such as ZnO as well as by synthesizing active photonic crystals directly from colloids made of organic dye-polymer composites. The emission characteristics of these active species are modified by the photonic crystal    environment due to the anisotropic stop band. It has been possible to fabricate photonic crystal heterostructures as well as photonic crystal waveguides for building functionalities into photonic integrated circuits.  BJ93GJCCMXAR

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.

Cusat Previous Years Question Papers B.Tech all branch

Civil Engineering Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Computer Science     Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Electrical and Electronics Engineering Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Electronics and Communication  Engineering Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Information Technology Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Mechanical Engineering Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

Safety and Fire Engineering Semester I Semester II Semester III Semester IV Semester V Semester VI Semester VII Semester VIII

reference :http://dspace.cusat.ac.in

Cryptography

Security of information results from the need for Private transmission of messages. It is very essential that Security coverage should be provided to the computer systems, including to security to communication channels

Cryptography means hidden writing. Cryptography is used to protect information to which illegal access is possible and where other protective measures are inefficient

The basic idea in cryptography is to take a message in ordinary language, called plain text. This is transformed in some way to produce cipher text. The cipher text can now be sent to the correspondent. He uses another transformation to recover the plain text from the cipher text. The plain text is encrypted or hidden by the first transformation to obtain the cipher text. The cipher text is decrypted by another transformation to obtain the plain text once again. After encryption, cipher text can be transmitted over a data link or stored in a file

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CS & IT SEMINAR

• AUTOSAR
• BEHAVIORAL CLONING
• Boids
• CELL PHONE VIRUSES AND SECURITY
• Chatterbot
• Content Srambling System
• COOPERATIVE LINUX
• CYBORG
• Datagram Congestion Control Protocol (DCCP)
• DeCSS
• Distributed Quota Enforcement for Spam
• DNA AND DNA COMPUTING IN SECURITY
• Earth Simulator
• Electronic money
• Elliptical Curve Cryptography
• Extensible Firmware Interface
• Ferroelectric Random Access Memory
• Holographic Versatile Disc
• Intel Virtualization Technology
• Interactive Television
• INTERPLANETARY INTERNET
• IP Multimedia Subsystem (IMS)
• JAVA MANAGEMENT EXTENSION (JMX)
• MAGNATORESISTIVE RAM (MRAM)
• Mathematical markup languages
• MPEG-7
• NEW SENSOR TECHNOLOGY
• OpenRAN
• OVONIC UNIFIED MEMORY
• PLASMA PANEL DISPLAY
• Quantum dot cellular automaton
• QUANTUM DOT LASERS
• Real-time Transport Protocol
• Simultaneous Multithreading
• Simultaneous multithreading
• Software Radio
• SYMBIAN OS
• VoIP in Mobile Phones
• WIRELESS MESH NETWORKS
• ZFS Filesystem

ELECTRONICS SEMINAR TOPICS

• ADVANCED IC PACKAGING TECHNOLOGIES
• Asymmetric digital subscriber line(ADSL)
• Blu Ray Disc
• Blue Laser Could Lead to Autism Cure
• Bluetooth Based Smart Sensor Networks
• CELLULAR TECHNOLOGY
• CLUSTERING TECHNOLOGY
• Digital T.V
• Direct sequence code division multiple access (DS-CDMA)
• DLP Projector
• Dynode
• Efficient New Light Unfolds Like Paper
• Face Recognition Technology
• FLUORESCENT MULTILAYER DISC (FMD)
• HAVi
• Human Ear Inspires Universal Radio
• Hydrophone
• IDMA - Future of Wireless Technology
• Light Emitting Polymers
• Microbe-Powered 'Fart' Machine Stores Energy
• Microvia Technology
• MIDI
• Multimedia messaging Service
• OFDMA
• Organic LED
• Protein Memories for Computers
• Push Technology
• Quantum-dot Cellular Automata
• Single electron tunneling (SET) transistor
• Smart Dust
• Smart sensors
• Space Mouse
• Surface conduction Electron emitter Display (SED)
• Surface-conduction Electron-emitter Display (SED)
• Surround sound system
• Thermomechanical Data Storage
• Thin Displays
• Thought Translation Device
• Tunable lasers
• Ultra Conductors
• Virtual Keyboard
• Virtual Retinal Display
• VOICE MORPHING
• VoIP in Mobile Phones
• White LED
• Wibree
• Wireless LED