Digital Watermarking

Introduction :- :-
 
In recent years, the distribution of works of art, including pictures, music, video and textual documents, has become easier. With the widespread and increasing use of the Internet, digital forms of these media (still images, audio, video, text) are easily accessible. This is clearly advantageous, in that it is easier to market and sell one's works of art. However, this same property threatens copyright protection. Digital documents are easy to copy and distribute, allowing for pirating. There are a number of methods for protecting ownership. One of these is known as digital watermarking. 

Digital watermarking is the process of inserting a digital signal or pattern (indicative of the owner of the content) into digital content. The signal, known as a watermark, can be used later to identify the owner of the work, to authenticate the content, and to trace illegal copies of the work. Watermarks of varying degrees of obtrusiveness are added to presentation media as a guarantee of authenticity, quality, ownership, and source.


Abstract

Digital watermarking is an extension of steganography, is a promising solution for content copyright protection in the global network. It imposes extra robustness on embedded information. Digital watermarking is the science of embedding copyright information in the original files. The information embedded is called watermarks.

Digital Watermark Types And Terms

Watermarks can be visible or invisible:

a.     Visible watermarks are designed to be easily perceived by a viewer (or listener). They clearly identify the owner of the digital data, but should not detract from the content of the data. 

b.     Invisible watermarks are designed to be imperceptible under normal viewing (or listening) conditions; more of the current research focuses on this type of watermark than the visible type.

A further classification of watermarks is into fragile, semi-fragile or robust: 

a.     A fragile watermark is embedded in digital data to for the purpose of detecting any changes that have been made to the content of the data. They achieve this because they are distorted, or "broken", easily. Fragile watermarks are applicable in image authentication systems.

Digital Watermarking
 Purposes Of Digital Watermarks

1.     They aim to mark digital data permanently and unalterably, so that the source as well as the intended recipient of the digital work is known. Copyright owners can incorporate identifying information into their work. 

2.     With a tracking service, owners are able to find illegal copies of their work on the Internet. 

3.     Watermarks can be used to identify any changes that have been made to the watermarked data.

The Digital Watermark

Digital watermarking is a technology for embedding various types of information in digital content. In general, information for protecting copyrights and proving the validity of data is embedded as a watermark.

A digital watermark is a digital signal or pattern inserted into digital content. The digital content could be a still image, an audio clip, a video clip, a text document, or some form of digital data that the creator or owner would like to protect. The main purpose of the watermark is to identify who the owner of the digital data is, but it can also identify the intended recipient.

Why do we need to embed such information in digital content using digital watermark technology? The Internet boom is one of the reasons. It has become easy to connect to the Internet from home computers and obtain or provide various information using the World Wide Web (WWW).

All the information handled on the Internet is provided as digital content. Such digital content can be easily copied in a way that makes the new file indistinguishable from the original.  Then the content can be reproduced in large quantities.

Authentication

Authentication identifies if content has been altered or falsified. For example digital watermarking can verify authenticity and identify counterfeiting as a second layer of security for encrypted content. The presence of digital watermark and/or continuity of watermark can help ensure that the content has not been altered.

Conclusion

Digital watermarks have been used in the last few years to protect the ownership of digital data. Various techniques developed make use of the human audio-visual system. Legitimate business and webmasters have nothing to fear from copyright law or new form of on-line enforcement technology found in digital watermarks and tracking services.               
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Air Powered Cars

Abstract :- :- 

This seminar is to explain the working of air powered cars. These type of cars will run on compressed air instead of gasoline .The car is powered by a two cylinder compressed air engine. The air powered car is also called as a low pollution or zero pollution cars. Since the car runs on compressed air it is environmentally friendly.

Introduction

Have you been to the gas station this week? Considering that we live in a very mobile society, it's probably safe to assume that you have. While pumping gas, you've undoubtedly noticed how much the price of gas has soared in recent years. Gasoline which has been the main source of fuel for the history of cars, is becoming more and more expensive and impractical (especially from an environmental standpoint). These factors are leading car manufacturers to develop cars fueled by alternative energies. Two hybrid cars took to the road in 2000, and in three or four years fuel-cell-powered cars will roll onto the world's highways.

Air powered cars runs on compressed air instead of gasoline. This car is powered by a two cylinder compressed engine. This engine can run either on compressed air alone or act as an IC engine. Compressed air is stored in glass or fiber tanks at a pressure of 4351 psi.

Compressed Air Tanks

One of the most frequently asked questions is about the safety of the compressed air storage tanks. These tanks hold 90 cubic meters of air compressed to 300 bars. Many people ask whether this system is dangerous in case of an accident and if there is a risk of explosion. The answer is NO. Why? Because these are the same tanks used to carry the liquid gas used by buses for public transport. The tanks enjoy the same technology developed to contain natural gas. They are designed and officially approved to carry an explosive product: methane gas.


In the case of a major accident, where the tanks are ruptured, they would not explode since they are not metal. Instead they would crack, as they are made of carbon fiber. An elongated crack would appear in the tank, without exploding, and the air would simply escape, producing a loud but harmless noise. Of course, since this technology is licensed to transport an inflammable and explosive gas (Natural gas), it is perfectly capable inoffensive and non-flammable air.


Air Powered Cars PPT


Working

Air powered cars run on compressed air instead of gasoline. Since the car is working on air there is no pollution. A two cylinder, compressed air engine, powers the car. The engine can run either on compressed air alone or act as an internal combustion engine. Compressed air is stored in fiber or glass fiber tanks at a pressure of 4351 pounds per square inch. The air is fed through an air injector to the engine and flows into a small chamber, which expands the air. The air pushing down on the piston moves the crankshaft, which gives the vehicle power.

This car is also working on a hybrid version of their engine that can run on hybrid version of their engine that can run on traditional fuel in combination with air. The change of energy source is controlled electronically. When the car is moving at speeds below 60kph,it runs on air. At higher speeds, it runs on a fuel such as gasoline diesel or natural gas.

How Does The Electrical System Works?

Guy Negre, the inventor of the MDI engine, acquired the patent of an interesting invention for the electrical installation of the vehicle. It is a system based on the radio emission picked up by micro controllers installed in each one of the electrical devices of the car, which allows there to be one sole cable for the whole car. That is to say, that instead of using one cable for each device (lights, interior car lights, indicators, etc), it uses one cable for the whole car. The two obvious advantages are the simplicity of installation and repairs of the system, and the reduction of weight by 22kg.

The Dual Energy System

The engine can be equipped with and run on dual engines. Fossil fuels and compressed air and incorporate a reheating mechanism between the storage tank and the engine. This mechanism allows the engine to run exclusively on fossil fuel, which permits compatible autonomy on the road. While the car is running on the fossil fuel, the compressor air tanks. The control system maintains a zero pollution emission in the city at speeds upto 60 km per hour.

The air filter

The air compressed engine works on with both air taken from the atmosphere and air pre compressed in tanks. Air is compressed by the on board compressor or at service stations equipped with a high-pressure compressor.

Before compression the air must be filtered to get rid of any impurities that could damage the engine. Carbon filters are used to eliminate dirt, dust, humidity and abundant abrasive particles that unfortunately exist in the air from our cities.

Cryogenic Heat Engine

Another version of an air-powered car is being developed by researchers at the University of Washington using the concept of a steam engine, except there is no combustion. The Washington researchers use liquid nitrogen as the propellant for their LN2000 prototype air car. The researchers decided to use nitrogen because of its abundance in the atmosphere -- nitrogen makes up about 78 percent of the Earth's atmosphere -- and the availability of liquid nitrogen.
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Google App Engine

Abstract :- 

Google App Engine was first released as a beta version in April 2008. It is a platform for developing and hosting web applications in Google-managed data centers. Google’s App Engine opens Google’s production to any person in the world at no charge. Much like Google gives us all free email with an amazing amount of long term storage, we now have the ability to run the software that we write in Google’s data centers.

Google App Engine is cloud computing technology. Google App Engine is software that facilitates the user to run his web applications on Google infrastructure. It is more reliable because failure of any server will not affect either the performance of the end user or the service of the Google.

Introduction

Google App Engine lets you run your web applications on Google's infrastructure. App Engine applications are easy to build, easy to maintain, and easy to scale as your traffic and data storage needs grow. With App Engine, there are no servers to maintain: You just upload your application, and it's ready to serve your users.

You can serve your app from your own domain name (suc h as http://www.example.com/) using Google Apps. Or, you can serve your app using a free name on the appspot.com domain. You can share your application with the world, or limit access to members of your organization.
Google App Engine supports apps written in several programming languages. With App Engine's Java runtime environment, you can build your app using standard Java technologies, including the JVM, Java servlets, and the Java programming language—or any other language using a JVM-based interpreter or compiler, such as JavaScript or Ruby. App Engine also features a dedicated Python runtime environment, which includes a fast Python interpreter and the Python standard library. The Java and Python runtime environments are built to ensure that your application runs quickly, securely, and without interference from other apps on the system.


Google App Engine seminar
Working Of Google App Engine

Creating an App Engine application is easy, and only takes a few minutes. And it's free to start: upload your app and share it with users right away, at no charge and with no commitment required.

Google App Engine applications can be written in either the Java or Python programming languages. The Steps for how to create an application and deploy on app engine is shown below.

Python Runtime Environment

With App Engine's Python runtime environment, you can implement your app using the Python programming language, and run it on an optimized Python interpreter. App Engine includes rich APIs and tools for Python web application development, including a feature rich data modeling API, an easy-to-use web application framework, and tools for managing and accessing your app's data. You can also take advantage of a wide variety of mature libraries and frameworks for Python web application development, such as Django.

The Python runtime environment uses Python version 2.5.2. Additional support for Python 3 is being considered for a future release. The Python environment includes the Python standard library. Of course, not all of the library's features can run in the sandbox environment. For instance, a call to a method that attempts to open a socket or write to a file will raise an exception. For convenience, several modules in the standard library whose core features are not supported by the runtime environment have been disabled, and code that imports them will raise an error.

Application code written for the Python environment must be written exclusively in Python. Extensions written in the C language are not supported. The Python environment provides rich Python APIs for the data store, Google Accounts, URL fetch, and email services. App Engine also provides a simple Python web application framework called webapp to make it easy to start building applications.

Billing and Budgeting Resources

Each App Engine application can consume a certain level of computing resources for free, controlled by a set of quotas. Developers who want to grow their applications beyond these free quotas can do so by enabling billing for their application and using Google Checkout to set a daily resource budget, which will allow for the purchasing of additional resources if and when they are needed. App Engine will always be free to get started, and after you've enabled billing for your app all usage up to the free quotas will remain free.
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CorDECT

Abstract:-

This report describes a new wireless local loop system for rapid expansion of telecom services developed under a joint project involving Indian scientists form Indian Institute Of Technology, Chennai, Midas technology and Analog Devices Inc., USA. The new system, called corDECT, is based on microcellular architecture and uses a modest bandwidth of 20MHz to provide voice, fax, and data communication in low as well as very high subscriber density environments. The high capacity at a modest bandwidth is made possible without prior frequency planning through a completely decentralized channel allocation procedure called dynamic channel selection. This technology provides cost-effective simultaneous high quality voice and data connectivity, a voice communication using 32Kbps ADPCM and Internet connectivity at 35\70 Kbps. This report discusses the relevance of corDECT in the context of current trends towards wireless systems, contrasts the microcellular architecture of corDECT with existing wireless systems based on macrocellular architectures, and outlines its market potential.

Introduction

A new wireless local loop system to eliminate the physical connections between telephone exchanges and subscribers has just hit the market after a two-year long joint research effort by Indian and US engineers. The new system, called corDECT, is said to offer significant cost-savings, rapid installation, and improved reliability over traditional connections based on copper cables. It is based on a microcellular architecture that is said to offer cost and operational advantages over wireless/mobile telephone systems based on macrocellular architectures. The corDECT system is based on the European Digital Enhanced Cordless Telecommunications standard that uses a modest bandwidth of 20MHz in the 1880-1900 MHz range and does not require prior frequency planning necessary in conventional mobile cellular systems. The corDECT technology uses relatively low-cost, easy-to-install subsystems and can serve relatively high subscriber density environments –several thousands of subscribers per square kilometer. Four Indian companies have bought the technology for domestic manufacture. Its developers believe there is a large market potential in the Asia-Pacific region and in other developing countries. This report will describe the CorDECT wireless local loop system and its subsystems and compare the microcellular architecture of corDECT with macrocellular architectures employed in many wireless telephone systems.

CorDECT Seminar PPT



DECT Interface Unit (DIU)

        The DIU is heart of the CorDECT system It serves as an interface between the PSTN and CBS.The DIU is connected to the CBS by three cables that carry data in ISDN format and device and derive the power to CBS. Each DIU can be connected to a maximum of 20 CBS. Each DIU is connected to PSTN through standard E1 lines. Each CBS can be located up to four kilometers from a DIU.

Network Layer Protocol

The DECT network protocol is defined for the control plane (C plane) only. It provides the means to request, allocate, manage, and deallocate key resources in the central system and the portable. The capabilities of the DECT system in terms of its flexibility to support a wide range of applications and interface to diverse networks is determined by the characteristics of the network protocol were drawn from the ISDN user-network protocol at layer 3 (ITU-T Recommendation Q.931) and to some extend from the GSM layer 3 protocol. Since, however, the DECT architecture and requirements differ considerably from ISDN and GSM, DECT network layer protocol is essentially modu8lar and it is intended to support a number of protocol functions. Some of the protocols, which the network layer supports, are given below.

The main functions of the DIU are
  •         Enabling cell formatting.
  •          Billing.
  •          Administration and monitoring of the network.
  •          Interfacing between PSTN and CBS, and delivering signals without the use of wires to the subscriber.
  •          Providing power to the base station.

Management Entity (MGE)

        The management entity (MGE) is responsible for a number of functions in DECT that involve only one side of the communication link and as such do not appear in an OSI layer. These include such functions as radio resource control (choice of free channels, assessment of channel quality), mobility management (registration of DECT portables), and error handling (call termination at radio link interruption).

 Radio Aspects Of CorDect

In Europe the 1880-1900 MHz band has been set-aside for DECT. To utilize the available 20 MHz band in an efficient and flexible manner for supporting voice and data applications, the DECT standard provides for space, frequency, and time distribution, Space dispersion in DECT is supported through the frequency reuse feature based on the cellular concept. To provide frequency distribution, the available spectrum is segmented into 10 carrier frequencies (frequency channels) from 1881.792MHz with separation of 1.728MHz [i.e. by deploying frequency division multiple accesses (FDMA)]. Time distribution is achieved by using time division multiple accesses (TDMA), where by each frequency channel supports 12 duplex time slots or 32 Kb/s channels.

Radio Specifications of CorDECT

Access method           :       TDMA
Spectrum allocation    :       1880-1900MHz
Carrier spacing           :       1728 KHz
Number of carriers      :       10
Channels/Carrier         :       12
Modulation                 :       GFSK
Transmission rate       :       1152Kb/s
Frame duration          :       10ms
Speech coding            :       32Kb/s ADPCM
Peak output power     :       250mW

Conclusion

The corDECT wireless local loop system offers relatively low cost and rapid installation of telecom services in areas with even high subscriber density environments. This microcellular system relies on a modest bandwidth of 20MHz for the entire country. Two or three DECT wireless local loop systems and DECT based local area networks could coexist in the same area without interfering with one another -- all operating on the same 20MHz bandwidth.  The high capacity is achieved not by using low bit-rate compression techniques but with toll quality ADPCM or PCM voice coding. The microcellular system can provide ADPCM (32kbps) or PCM (64kbps) and even ISDN (128kbps) services to users. Its developers describe it as a "future proof" system.



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Animatronics


 Abstract:-

        Animatronics is a cross between animation and electronics. Basically, an animatronic is a mechanized puppet. It may be preprogrammed or remotely controlled. An abbreviated term originally coined by Walt Disney as "Audio-Animatronics" (used to describe his mechanized characters), can actually be seen in various forms as far back as Leonardo-Da-Vinci's Automata Lion, (theoretically built to present lillies to the King of France during one of his Visits), and has now developed as a career which may require combined talent in Mechanical Engineering, Sculpting / Casting, Control Technologies, Electrical / Electronic, Airbrushing, Radio-Control. Long before digital effects appeared, animatronics were making cinematic history. The scare generated by the Great White coming out of the water in "Jaws" and  the tender otherworldliness of "E.T." were its outcomes. The Jurassic Park series combined digital effects with animatronics. It is possible for us to build our own animatronics by making use of ready-made animatronic kits provided by companies such as Mister Computers.

What Is Animatronics

        Animatronics is a combination of animation and electronics. What exactly is an animatronic? Basically, an animatronic is a mechanized puppet. It may be preprogrammed or remotely controlled. The animatronic may only perform a limited range of movements or it may be incredibly versatile. The scare created by  the Great White coming out of the water in "Jaws" and the tender otherworldliness of "E.T." are cinematic effects that will not be easily forgotten. Later animatronics was used together with digital effects. Through the precision, ingenuity and dedication of their creators, animatronics creatures often seem as real to us as their flesh-and-blood counterparts.





 Introduction

        The first use of Audio-Animatronics was for Walt Disney's Enchanted Tiki Room in Disneyland, which opened in June, 1963. The Tiki birds were operated using digital controls; that is, something that is either on or off. Tones were recorded onto tape, which on playback would cause a metal reed to vibrate. The vibrating reed would close a circuit and thus operate a relay. The relay sent a pulse of energy (electricity) to the figure's mechanism which would cause a pneumatic valve to operate, which resulted in the action, like the opening of a bird's beak. Each action (e.g., opening of the mouth) had a neutral position, otherwise known as the "natural resting position" (e.g., in the case of the Tiki bird it would be for the mouth to be closed). When there was no pulse of energy forthcoming, the action would be in, or return to, the natural resting position.

Jurassic Park

        Long before digital effects appeared, animatronics were making cinematic history. But it was in Jurassic park that the best possible combination of animatronics and digital effects were used together. Spinosaurus was  a new dinosaur animatronic created for "Jurassic Park III" by Stan Winston Studio (SWS). SWS worked with Universal Studios and the film's production team to develop the Spinosaurus design. Below lies the discussion of the amazing process that creates and controls a huge animatronic like this dinosaur!



1.   Jurassic Machines
2.   Dinosaur Evolution
3.   In the Beginning
4.   Creature Creation
5.   Putting it together
6.   Making it Move
                              7. Monster Mash

Electronic

         Another group develops the electronic control systems needed to operate the animatronic. Typically starting from scratch and creating their own custom circuit boards, these engineers are essentially building giant remote-controlled toys. Almost all of the movement of the Spinosaurus will be manipulated by specialized remote-control systems known as telemetry devices.

Structural

         All of the electronic and mechanical components need something to attach to and control, and the skin must have a frame to maintain its shape. This is done by building a plastic and steel frame. To increase the realism, and because it is the natural way to design it, the frame of the Spinosaurus, as well as most other creatures made by SWS, resembles the actual skeleton of the beast. This skeletal frame is largely comprised of graphite, a synthetic material known for its strength and lightness.

Surface 

        The "skin" of the Spinosaurus is made from foam rubber, which is a very light, spongy rubber that is made by mixing air with liquid latex rubber and then curing (hardening) it. While there are other compounds, such as silicone and urethane, that are stronger and last longer, foam rubber is used because it is much easier to work with. The solution is poured into each mold and allowed to cure. As mentioned earlier, parts of the frame are embedded with the foam rubber at certain points. To further strengthen the skin, a piece of fabric is cut to size and embedded in the foam rubber after it is poured into the mold. Once cured, each piece of skin is pulled from its mold.

What Is An Animatronics Kit?

        Everything you need (except batteries and imagination) is included in our easy-to-use kit. Connect the cable to your PC's serial port, install the software and you're ready to start. No soldering or programming skills required. If you can use Windows you can use this Animatronics Kit . The software allows you to record the movements of hobby servos (up to two billion moves) and play them back exactly as recorded. Make your creation come to life!

Conclusion

        Creating a good animatronics figure that is able to perform constantly without fail requires many special skills and lots of technical know how.  Before assuming the task of creating an animatronic figure, you  should have a strong hold on how these things are constructed and be willing to spend a pretty penny on equipment and materials.


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